Torque converter - European Patent Office

Europäisches Patentamt
(19)
European Patent Office
*EP000997666B1*
Office européen des brevets
(11)
EP 0 997 666 B1
EUROPEAN PATENT SPECIFICATION
(12)
(45) Date of publication and mention
(51) Int Cl.7:
of the grant of the patent:
31.03.2004 Bulletin 2004/14
F16H 41/28
(21) Application number: 99121403.2
(22) Date of filing: 27.10.1999
(54) Torque converter
Drehmomentwandler
Convertisseur de couple
(84) Designated Contracting States:
(74) Representative: Schmitt, Armand et al
DE GB
Office Ernest T. Freylinger S.A.,
B.P. 48
8001 Strassen (LU)
(30) Priority: 30.10.1998 JP 31005998
(43) Date of publication of application:
(56) References cited:
03.05.2000 Bulletin 2000/18
DE-A- 19 814 362
FR-A- 2 190 209
US-A- 4 825 521
(73) Proprietors:
• KUBOTA IRON WORKS CO., LTD.
Hiroshima-shi, Hiroshima-ken (JP)
• FUJI JUKOGYO KABUSHIKI KAISHA
Tokyo (JP)
(72) Inventors:
EP 0 997 666 B1
• Yamanaka, Shigeaki
Aki-ku, Hiroshima-shi, Hiroshima (JP)
• Kobayashi, Toshio
Shinjuku-ku, Tokyo (JP)
DE-C- 924 724
US-A- 2 745 354
• PATENT ABSTRACTS OF JAPAN vol. 014, no.
237 (M-0976), 21 May 1990 (1990-05-21) & JP 02
062460 A (AISIN AW CO LTD), 2 March 1990
(1990-03-02)
• PATENT ABSTRACTS OF JAPAN vol. 017, no.
392 (M-1450), 22 July 1993 (1993-07-22) & JP 05
071611 A (NISSAN MOTOR CO LTD), 23 March
1993 (1993-03-23)
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give
notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in
a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art.
99(1) European Patent Convention).
Printed by Jouve, 75001 PARIS (FR)
EP 0 997 666 B1
Description
BACKGROUND OF THE INVENTION
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[0001] The present invention relates to a torque converter used for an automatic transmission mechanism of a vehicle
as described in the preamble of claim 1 and two methods of manufacturing a front cover and an impeller shell of a
torque converter as described in the preamble of claims 11 and 16.
[0002] The torque converter of an automobile is equipped with a lock-up clutch which functions to improve fuel consumption of an engine while giving two operation modes, i.e. one operation mode (torque converter state) and the
other operation mode (lock-up state). In the first operation mode (torque converter state), an output element is rotated
with increasing torque by a reaction force of a stator while circulating a hydraulic oil to an impeller of the output element
(generally, turbine runner) and a reaction element (generally, stator) by the rotation of an impeller of an input element
(generally, pump impeller) driven by the engine.
[0003] And in the second operation mode (lock-up state), the engine turns the output element by coupling the input
and output element by fixing the lock-up clutch.
[0004] The Japanese Patent Laid-open Publication No. HEI 7-33861 of the same applicant discloses conventional
examples of a front cover and a pump impeller which are constructional elements of a torque converter equipped with
a lock-up mechanism of the type mentioned above.
[0005] In such conventional examples, a rotating power from the engine is transmitted to a flange portion, which
performs as an inertia function. And a starter gear is meshed with an annular ring gear. The flange and the gear are
formed on an outer peripheral surface of the torque converter. The ring gear is meshed with a pinion of a starter motor
at a starting time of the engine operation for transmitting the rotating force of the starter motor to a crank shaft of the
engine.
[0006] Fig. 1 shows a structure of the torque converter provided with the conventional lock-up mechanism mentioned
above.
[0007] With reference to Fig. 1, the torque converter 1 is composed of a pump impeller 3 formed by integrally coupling
an impeller 2a to an impeller shell 2, a turbine runner 4 and a stator 5. The impeller shell 2 of the pump impeller 3 is
integrally coupled to a front cover 6 by welding. The front cover 6 is formed on an outer peripheral surface with an
annular flange portion 7. And a drive plate 9 coupled to a engine crank shaft 8 is fastened by means of bolt. A ring
gear 10 for the stator 5 is provided at an outer peripheral surface of the impeller shell 2.
[0008] The detailed structure of the conventional torque converter will be further explained hereunder with reference
to Fig. 1.
[0009] The turbine runner 4 is mounted to a turbine hub 12 by rivets, for example, and an input shaft 13 is connected
to the turbine hub 12 in a spline coupling engagement. The stator 5 is supported by a hollow fixed shaft 17 through an
outer race 14. A sprag 15 and an inner race 16 constitute a one-way clutch to be rotatable in one direction. The hollow
fixed shaft 17 is fastened to a housing 19 of an oil pump 18 by bolts and is coupled to the inner race 16 in a spline
engagement.
[0010] An oil pump driving shaft 20 in shape of sleeve is provided at a shaft core portion of the impeller shell 2 of
the pump impeller 3, and an inner rotor 21 of the oil pump 18 is coupled to the oil pump driving shaft 20 so as to be
driven rotatably.
[0011] One example of such coupling structure of the inner rotor 21 to the oil pump driving shaft 20 of the impeller
shell 2 is disclosed in the Japanese Utility Model Laid-open Publication No. HEI 5-34348). That is, a width across flat
portion is formed on an outer periphery of a front (tip) end portion of the oil pump driving shaft 20, and another width
across flat portion is formed to an inner surface of the inner rotor 21 of the oil pump 18, when both widths across flat
portions are engaged, the oil pump driving shaft 20 and the inner rotor 21 of the oil pump 18 are coupled to be driven
in the rotational direction.
[0012] Further, an outer periphery of a cylindrical portion at an approximately axial central portion of the oil pump
driving shaft 20 is rotatably supported by an inner peripheral surface of a bush 22 fixed to the housing 19 of the oil
pump 18 so as to bear the driving load of the oil pump 18 at this portion. Accordingly, a driving load in proportion to a
discharge pressure (line pressure) of the oil pump 18 is applied to the width across flat portion of the oil pump driving
shaft 20 and the portion thereof supported by the bush 22.
[0013] Stator collars 23a and 23b are mounted on both sides of the sprag 15 of the one-way clutch, and thrust
bearings 24a and 24b are interposed between a pilot boss portion 32 as described hereinafter and the turbine hub 12
and between the stator collar 23b and the oil pump driving shaft 20, respectively.
[0014] The pump impeller 3 driven by the rotation of the crank shaft 8 (of the engine) acts to circulate the hydraulic
oil filling in a torque converter chamber 25, and the hydraulic oil circulates in passages of the respective impellers of
the pump impeller 3, the turbine runner 4 and the stator 5, whereby the turbine runner 4 is rotated while increasing the
torque by the reaction force due to the operation of the stator 5, and the rotating force is transmitted to the input shaft
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13 through the turbine hub 12 and then to an automatic transmission mechanism or non-stage transmission mechanism,
not shown.
[0015] A lock-up clutch hub 27 of a lock-up clutch 26 is fastened to the turbine hub 12 by rivets, and the lock-up
clutch hub 27 is provided with a torsional damper 28 for damping a shock at a time of clutch engagement and for
absorbing vibrations or noises of the driving system.
[0016] The lock-up clutch 26 is provided with a lock-up piston 29 at a portion between the lock-up clutch hub 27 and
the front cover 6. And the lock-up piston 29 is fitted to the turbine hub 12 in a fashion that the inner peripheral portion
of the lock-up piston 29 is slidable in an axial direction of the turbine hub 12 in a liquid tight manner with respect to the
outer peripheral portion of the turbine hub 12. The inside inner peripheral portion of the torsional damper 28 is splineengaged with the outer peripheral portion of the lock-up clutch hub 27. Further, the lock-up piston 29 is provided with
a lock-up facing 30 on a side surface portion on the side of the front cover 6.
[0017] A front hydraulic chamber 31 is defined between the lock-up piston 29 and the front cover 6. The engine crank
shaft 8 is formed with a center hole to which a pilot boss portion 32 provided to the front cover 6 is fitted so as to achieve
a rotational axis alignment of the torque converter 1. The front hydraulic chamber 31 is communicated with an oil
passage 33 formed within the input shaft 13 and then communicated with a control valve of a hydraulic controller of
the automatic transmission mechanism or non-stage transmission mechanism, not shown.
[0018] The torque converter 1 has an oil passage between the hollow fixed shaft 17 and the oil pump driving shaft
20. The passage is communicated to a groove formed on the side surface of the thrust bearing 24b disposed between
the stator collar 23b and the oil pump driving shaft 20, the passage then being communicated with the hydraulic controller.
[0019] At the lock-up time, a hydraulic pressure is applied to the turbine-side side surface of the lock-up piston 29
from the inside of the torque converter 1 through the oil passage between the stator collar 23b and the oil pump driving
shaft 20, and at the same time, the pressurized oil in the front hydraulic chamber 31 is drained thereby to cause a
pressure difference between the front and rear portions of the lock-up piston 29 (so as to make the hydraulic pressure
in the front hydraulic chamber 31 smaller than that in the torque converter). Thus, the lock-up piston 29 is pushed to
the front cover 6 via the lock-up facing 30 to accomplish the lock-up state.
[0020] Further, when the lock-up state is released if required, the pressurized oil is supplied into the front hydraulic
chamber 31. And the hydraulic pressure in the oil passage from the inside of the torque converter 1 is controlled by
the control valve of the hydraulic controller to cause the pressure difference between the front hydraulic chamber and
the torque converter (so as to make the hydraulic pressure in the front hydraulic chamber 31 larger than that in the
torque converter), whereby the lock-up state is released.
[0021] In the torque converter 1 of the structure mentioned above, the outer hull has the front cover 6, the impeller
shell 2. And as the outer hull is generally formed by a thin steel plate projections (protrusions), thickened portions and
thinned portions may be formed partially as required.
[0022] The thickness may be changed if a certain strength or rigidity is required. And the outer hull portion of the
torque converter 1 has a thickened flanged portion 7 for receiving an inertia. And the outer hull has the drive plate
tightened by bolts, or there is provided a pilot boss portion 32 adapted to make align with the crank shaft 8 to the front
cover 6. These members are independently manufactured and integrally assembled together by means of welding, for
example, as shown in Fig. 2.
[0023] The impeller shell 2 will be manufactured such as shown in Fig. 3. That is, the ring gear 10, the sleeve-shaped
oil pump driving shaft 20 and so on, which are independently manufactured, are coupled to the outer peripheral portion
of the impeller shell 2 formed of a thin iron plate and the inner peripheral portion thereof, respectively, by welding, for
example.
[0024] A centrifugal force is generated in accordance with the increase of the engine revolution, an axial thrust force
is generated due to the circulation of the hydraulic fluid through the pump impeller 3, the turbine runner 4 and the stator
5, in this order, and a working force of the lock-up clutch 26 is also generated. These forces are applied to the outer
structural members or portions constituting the outer hull of the torque converter 1. For this reason, it is necessary for
the outer structural members such as impeller shell 2 and the front cover 6 to operate with withstanding against such
forces and suppressing the deformation such as axial swelling thereof in an allowable predetermined value. In this
regard, for example, it is preferred that the front cover 6 is formed of an iron plate having a relatively large thickness
of about 4.5 to 6 mm and the impeller shell 2 is formed of an iron plate having a thickness of about 3 to 4 mm.
[0025] In the prior art mentioned hereinbefore, the sleeve-shaped (cylindrical) oil pump driving shaft 20 integrally
coupled to the impeller shell 2 is formed at its rear end portion with width across flat portion which is fitted to the width
across flat portion formed to the inner peripheral portion of the inner rotor 21 of the oil pump 18 thereby to rotate the
pump, and furthermore, the cylindrical portions, other than the width across flat portions are also fitted with high accuracy so as to achieve the rotational alignment between the oil pump driving shaft 20 and the oil pump rotor (including
inner rotor 21 and outer rotor).
[0026] Furthermore, a hydraulic pressure of the automatic transmission mechanism (i.e. pump discharge pressure
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or line pressure) generated by the inner rotor 21 of the oil pump 18 is applied to a projected area of the outer periphery
of the oil pump rotor, so that a load corresponding to the projected area acts on the fitting portion of the central cylindrical
portion of the oil pump shaft 20 and the inner rotor 21. The load acting on this fitting portion constitutes a moment load
corresponding to a distance from the bush 22 supporting the central portion of the oil pump driving shaft 20 to the fitting
portion of the inner rotor 21, and the moment load hence acts on the bush 22. The bush 22 axially supports the entire
structure of the torque converter, so that, other than the above load, an eccentric load or swing load due to the misalignment at the mounting time of the torque converter assembly to the drive plate 9 can be supported.
[0027] The structure of the outer hull of the torque converter mentioned above and the manufacturing process thereof
has provided the following problems.
[0028] That is, the front cover and the impeller shell comprising a plurality of parts which are respectively independently manufactured, and the parts are thereafter assembled integrally by means of welding, for example, so that many
processes are required, involving much cost as well as bad production efficiency. Furthermore, since, in general, the
body of the front cover is manufactured through a press working, a soft steel plate is generally used because of its well
formability (yieldability). However, it is necessary to increase the thickness of the soft steel plate in order to ensure the
strength and rigidity thereof, in the case of using for high revolution and high torque engines, because the front cover
body bears the centrifugal hydraulic pressure generated in the highly rotating torque converter and is subjected to the
thrust load from the turbine runner and the pressing load of the lock-up clutch. Accordingly, in spite of the fact that it
is important to achieve the light-weight requirement and vibration reducing requirement while ensuring the inertia moment required for a rotating member, it is difficult to prevent the structure from increasing of the weight, thus the problems
remaining unsolved.
[0029] Still furthermore, it is required for the torque converter of the automatic transmission mechanism or non-stage
transmission mechanism to accord (cooperate) with a lean combustion type engine or direct-injection type engine in
place of a conventional engine in the viewpoints of environmental pollution and improvement of fuel consumption.
However, in the torque converter having the outer hull of the conventional structure, the above viewpoints have been
easily handled by making thin the thickness of a member constituting the outer hull or mounting an inertial ring to a
vacant space. Therefore, it is very difficult for the member constituting the outer hull of the torque converter to have
the effective inertia moment against the strong accelerating force from stopping state of the automobile and the lightening of the engine due to the problem of vibration of the engine. Accordingly, the weight of the engine has been further
increased, constituting the further problems hindering a realization the lightening of weight or compact structure of the
engine.
[0030] Further, the oil pump driving shaft, having a thin sleeve shape, which is welded to the pump impeller, is hardened to provide substantially hardness of HRC18 by heat treatment because a transverse load due to the pump discharge pressure is applied to the fitting portion to the oil pump rotor and a load due to the pump driving torque is applied
to the pump rotor driving portion. However, in general, the pump discharge pressure in an automatic transmission
mechanism is about 1.5 to 1.8 Mpa, and that in a metal-belt type non-stage transmission mechanism is about 4 to 5
Mpa, and accordingly, when used for the automatic transmission mechanism, the drive shaft and the supporting bush
of the oil pump are easily broken by fatigue.
[0031] As a countermeasure to the above defects, there is considered a change to a material hardened by heat
treatment such as high-frequency wave (induction) heating and/or increasing of the thickness of the oil pump driving
shaft, or there is also considered an entire change of a support structure supporting the pump rotor. However, such
countermeasures will make large the entire structure of the apparatus, increase the weight thereof and increase the
manufacturing cost, which will hence constitute bars (barriers) for improving the production efficiency and the lightening
of the apparatus, thus providing problems.
[0032] Other embodiments of torque converters are disclosed in FR 2 190 209, DE 198 14 362 and US 2,745,354.
FR 2 190 209 describes a torque converter with a flangeless front cover that is welded to the drive plate. The oil pump
is driven by a sleeve-like driving shaft that is integrally coupled to the impeller shell. In the torque converter of DE 198
14 362, the crankshaft is directly coupled to the front cover. As described in US 2,745,354, the front cover has a welded
pilot boss portion.
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SUMMARY OF THE INVENTION
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[0033] An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior
art mentioned above and to provide a torque converter capable of reducing the manufacturing cost thereof, realizing
a light weight requirement without damaging the strength and rigidity of members constituting the outer hull of the
torque converter, effectively reducing or eliminating fatigue failure of an oil pump driving shaft and damage to a bush
rotationally supporting the oil pump driving shaft.
[0034] Other objects can be achieved according to the present invention by providing a torque converter as described
in claim 1.
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[0035] In a preferred embodiment, a liquid-tight brazing and a coating layer is formed to at least a portion, of an inner
peripheral side boundary portion of the flanged portion, which is short-circuited to a screw hole portion formed to the
flanged portion.
[0036] The sleeve-shaped oil pump driving shaft is formed integrally with the impeller shell through the plastic working
and the ring gear for the starter is integrally formed so as to form an increased thickness portion through the plastic
working. The ring gear for the starter is integrally formed to a rear portion of the outer periphery of the front cover
through a plastic working. The flanged portion and the ring gear for the starter are integrally formed through the plastic
working to the outer peripheral portion of the outer hull composed of the front cover and the impeller shell so that the
integrally formed portions perform an inertia function and a power transmission function.
[0037] At least either one of the front cover and impeller shell are formed, through a molding process, of a steel plate
material consisting of, in weight %, C: 0.2-0.6, Si: 0.01-0.1, Mn: 0.05-0.5, Ti: 0.01-0.1, B: 0.001-0.01, and Fe: residue.
An induction hardening is carried out to at least a portion, of the oil pump driving shaft, which is fitted to the rotor of
the oil pump and a bush fitting portion supported to a housing of an oil pump through the bush. An induction microwave hardening is also carried out to an inside surface of the oil pump driving shaft, which is opposed to a disc surface
of the stator through a thrust bearing.
[0038] The induction micro-wave hardening is also carried out to at least one of an inner surface of a disc portion of
the front cover, a surface thereof opposing to a turbine hub through a thrust bearing and a central protruded portion
thereof.
[0039] According to the present invention of the characters and structures mentioned above, the front cover and the
impeller shell constituting the outer hull of the torque converter are integrally formed, through the plastic working, with
the associated members such as the pilot boss portion, the flanged portion, the ring gear and the oil pump driving
shaft. Accordingly, in comparison with the conventional torque converter in which the associated members mentioned
above are independently formed and then assembled with the front cover and the impeller shell which are also independently formed, the productivity of the front cover and the impeller shell of the torque converter according to the
present invention provided with the associated members mentioned above can be improved and the manufacturing
cost can be hence reduced. In addition, as the respective members are integrally formed, unnecessarily thickened
portions are eliminated, thus realizing the light weight requirement of the entire structure of the torque converter.
[0040] Furthermore, welding works can be effectively eliminated to the ring gear for the starter and the flanged portion
through which the engine driving power is transmitted. The elimination of such welding works can prevent the formation
of irregularly thickened portion due to the welding and prevent the occurrence of defects which may be caused by the
welding. Therefore, the adjustment of rotational balance after the assembling of the torque converter can be easily
performed, and moreover, oil leakage due to the welding defect will be also prevented, whereby the quality of products
and the productivity can be improved.
[0041] Still furthermore, according to the present invention, the front cover and the impeller shell are formed of a
material including boron (B) in addition to carbon (C) of 0.5 weight %, so that the induction hardening can be effectively
applied to the members as required, thereby improving the strength and rigidity of the fitting portion between the oil
pump drive shaft and the oil pump rotor and the bush rotation support portion and the gear teeth of the ring gear to
prevent the portions or members from being damaged, worn and deformed.
[0042] Still furthermore, the front cover and the impeller shell can be formed from a steel plate having a thickness
thinner than that used for the conventional structure. Moreover, in a case where the engine is operated with a revolution
number increased in a red zone under the lock-up condition, a compound force of the centrifugal hydraulic pressure
acting on the torque converter and the lock-up clutch engaging load can be born and at least a permanent deformation
can be prevented from causing, even if a thin steel plate be used, by performing, as required, the micro-wave induction
hardening to or partially increasing the thickness of the outer peripheral bent portion at which large bending stress is
caused.
[0043] Still furthermore, in spite of the use of the thin steel plate while maintaining the high strength and rigidity, the
flanged portion formed to the outer periphery of the front cover is increased in thickness and the ring gear disposed to
the outer periphery of the impeller shell is also increased in thickness by a roll spinning process, so that the inertial
mass can be most effectively ensured to the outer peripheral portion of the torque converter without arranging an inertia
ring as additional member as that in the conventional structure, thus realizing the light weight requirement. In particular,
even in a case where it is required to improve an environmental pollution and fuel consumption in the use of a lean
combustion engine or direct-injection combustion engine, the inertia can be ensured and the light weight can be realized
while maintaining the improved productivity and reduced manufacturing cost.
[0044] The nature and further characteristic features of the present invention will be made further clear from the
following descriptions made with reference to the accompanying drawings.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0045]
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In the accompanying drawings:
Fig. 1 is a partial sectional view of a main portion of a torque converter of a conventional structure;
Fig. 2 is a sectional view showing a front cover of the torque converter of Fig. 1 for the explanation of a manufacturing
process thereof;
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Fig. 3 is a sectional view showing an impeller shell of the torque converter of Fig. 1 for the explanation of a manufacturing process thereof;
Figs. 4A to 4H are sectional views showing a manufacturing process in the illustrated order;
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Fig. 5 is a sectional view of the front cover of the torque converter of the present invention;
Fig. 6 is a sectional view corresponding to Fig. 4C showing another example of a front cover;
Figs. 7A to 7F are sectional views showing a manufacturing process of an impeller shell;
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Fig. 8 is a partial sectional view of an essential portion of the torque converter according to the present invention;
Figs. 9A and 9B are front views showing patterns formed to the front cover by micro-wave induction hardening; and
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Fig. 10 shows a sectional view of a front cover of the torque converter according to another embodiment of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
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[0046] A torque converter according to the present invention is entirely shown in Fig. 8, which is provided with improved impeller shell 102 and front cover 106 in comparison with those shown in Fig. 1, and preferred embodiments
thereof will be described hereunder with reference to Figs. 4 to 10, in which reference numerals are applied to members
or portions corresponding to those shown in Figs. 1 to 3.
[0047] Figs. 4A to 4H are views explaining plastic working steps of the front cover 106 in this order.
[0048] Fig. 4A shows a punch-out step for punching out a disc-shaped material 41 in a predetermined size, Fig. 4B
shows a step for forming a swelled or protruded portion 42 at a central portion of the material 41 through a press
working, and Fig. 4C shows a step for plastically forming a boss portion 45 constituting a pilot boss portion 132 of the
front cover 106 by placing the swelled portion 42 on a mold 43 composed of a pin 43a and a die 43b and then pressforming the swelled portion 42 from the upper side thereof by using a formed roller 44. In these steps, the material
volume of the swelled portion 42 is made larger than that of the boss portion 45, and accordingly, the thickness of the
boss portion 45 is made larger than a plate thickness of the material 41. That is, the thickness of the boss portion 45
is increased.
[0049] In the next step shown in Fig. 4D, a cylindrical portion 46 is formed to the outer peripheral portion of the
material 41 through a press working and a protrusion or projection 48 is formed, so as to project outward in an annular
shape from an inside portion by a roller 47, to a portion constituting a flanged portion 107.
[0050] In a step shown in Fig. 4E, the cylindrical portion 46 is pressed in an axial direction thereof, and according to
this pressing, buckling is formed to the protrusion 48 so as to provide a substantially Ω-shape in section. In a step
shown in Fig. 4F, the outer shape of the protrusion 48 is shaped by a roller 49 and the protrusion 48 is then pressed
and folded by upper and lower rollers 50a, 50b so as to form the flanged portion 107 having a semi-circular front end
shape in a step shown in Fig, 4G. Thereafter, in a step shown in Fig. 4H, the front end is shaped by a roller 51 so as
to provide a flat end shape, i.e. cylindrical shape of the flanged portion 107. Further, in the steps shown in Figs. 4F to
4H, a back-up die 52 is disposed to an inside portion of the cylindrical portion 46.
[0051] With reference to Fig. 5, the material 41 is thereafter entirely press-worked to provide the front cover shape
and a screw hole 107a is formed to the flanged portion 107 through a drilling work. In this step, if the bolt screw hole
107a is communicated with an abutment portion 53 formed by folding the protrusion 48 in the step shown in Fig. 4G,
an oil leakage may be caused. In order to obviate such defect, a brazing or coating treatment will be applied thereby
to form a coating layer, thus performing a fluid-tight sealing to that portion.
[0052] Fig. 6 shows another example for forming the pilot boss portion 132 from the swelled portion 42 formed to
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the material 41 of the front cover 106, and in this example, the swelled portion 42 is formed so as to provide a shape
aligning the shape of a mold 43 by means of a roller 44a having a small diameter.
[0053] Figs. 7A to 7F represent steps for the plastic working for forming the impeller shell 102.
[0054] In a step shown in Fig. 7A, a disc-shaped material 55 is punched out in a predetermined size, in a step shown
in Fig. 7B, the material 55 is shaped so as to provide a semi-spherical shape through a press working, and in a step
shown in Fig. 7C, a swelled or protruded portion 56 is formed to the central portion of the disc-shaped material 55
through a press working. In a step shown in Fig. 7D, the swelled portion 56 is subjected to a further press work so as
to provide a sleeve-shaped shaft portion and an upper end (front end) of this sleeve-shaped shaft portion is cut away
thereby plastically forming an oil pump driving shaft 120.
[0055] Thereafter, in a step shown in Fig. 7E, the material 55 is entirely press-worked so as to form an impeller shell
102 having a flanged portion 57 at the outer peripheral edge. In a step shown in Fig. 7F, the flanged portion 57 is
increased in thickness, by a roll spinning method, so as to form a thickened portion 58. A ring gear 110 for a starter is
worked through a rolling method or machining work.
[0056] Fig. 8 shows the torque converter 101 provided with the impeller shell 102 and the front cover 106 having the
structures mentioned above formed in accordance with the steps also mentioned above. The impeller shell 102 is
integrally coupled to an impeller 102a to form a pump impeller 103.
[0057] Hereunder, there will be described means for achieving purposes of lightening the weight of the torque converter and improving the strength and rigidity of the members constituting the same while ensuring the inertial mass.
[0058] A conventional front cover 6 and impeller shell 2 such as shown in Fig. 1 are formed of a material of SPC or
SPHC and have plate thicknesses of 4.9 mm and 3.2 mm, respectively. On the other hand, according to the preferred
embodiment of the present invention, the SPC material is changed to a material which is made by adding a small
amount of boron (B) to an alloy material having a steel plate base containing a carbon (C) of 0.25 weight % and to
which the induction hardening process is effectively performed. The SPC material has the best press formability, and
although a material containing C of 0.5 weight % with B added can provide a high strength, it will provide less press
formability. However, by reducing the plate thicknesses of the front cover 106 and the impeller shell 102, a working
stress of a conventional extent can be maintained, so that the above change of the material does not apply an adverse
effect for the production of the torque converter.
[0059] Furthermore, as the flanged portion 107 and the ring gear 110, are formed with the increased thicknesses,
the purpose of the lightening of the weight can be realized while ensuring the necessary inertial mass because the
portion 107 and the gear 110 are formed on the outer peripheral portions of the torque converter to be most effective
for increasing the inertial mass.
[0060] In consideration of the above matters, as the materials 41 and 55 for the front cover 106 and the impeller
shell 102, materials of S25CTiB containing titanium (Ti) and B and having thicknesses of 4.5 to 4.2 mm and 3.0 to 2.8
mm are utilized, respectively, in place of steel plate materials (SPC1) having thicknesses of 4.9 mm and 3.2 mm (JIS
standard). The respective components of these S25CTiB and SPC1 materials are shown in the following Table 1. Wt.
% means weight %.
Table 1
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Kind of
steel
C
S25CtiB
0.25
Si
Mn
P
S
0.06
0.39
0.01
0.008
≤ 0.04
≤ 0.045
Ti
B
0.06
0.004
3.2
(mm)
-
-
4.9
(mm)
(wt. %)
≤ 0.12
SPC1
45
50
≤ 1.2
≤ 0.5
(wt. %)
[0061] Further, although the respective components, other than phosphorus (P) and sulfur (S), of the steel plate
mentioned above usable for the present invention are different in the shapes and functions to be required, a steel of
the components in the range described in the following Table 2 will be suitably used, and further, P and S are substantially the same as those in the above S25CTiB. Wt.% means weight %.
Table 2
55
Plate
Thickness
C
Si
Mn
0.20 , 0.6% (wt%)
0.01 , 0.1%
0.05 , 0.5%
Ti
B
Elongation
7
EP 0 997 666 B1
Table 2 (continued)
C
Si
Mn
0.01 , 0.1 %
0.001 , 0.01 %
≥30 %
5
10
15
20
[0062] The front cover 106 and the impeller shell 102 after being plastically formed are strengthened as compared
with the conventional ones by effecting the induction hardening (including underwater induction hardening) to surfaces
of materials containing C of 0.25 weight % with B added, such as the fitting portion with the inner rotor 21 of the oil
pump 18, the rotational sliding portion with the bearing bush 22, the outer peripheral bent portion of the front cover
106 and the inside surface portion pressed by the lock-up piston 29, at which strength lowering or damage may be
caused by the plate thickness reduction.
[0063] In such operation, the induction hardening is not a full-surface hardening, and it will be preferred that the
hardening is performed so as to provide a pattern of radial lines as shown in Fig. 9A or pattern of rings as shown in
Fig. 9B.
[0064] In the above embodiment, although the ring gear 110 for the starter is located on the side of the impeller shell
102, the ring gear 110 may be formed through the plastic working to the outer peripheral portion of the front cover 106
together with the flanged portion 107 as shown in Fig. 10.
[0065] While the presently preferred embodiment of the present invention has been shown and described, it is to be
understood that this disclosure is for the purpose of illustration and that various changes and modifications may be
made without departing from the scope of the invention as set forth in the appended claim.
Claims
25
1.
30
35
A torque converter provided between a crankshaft (8) of an engine and an oil pump (18) mounted on an input shaft
(13), for transmitting a driving power of said engine not only to said input shaft while changing a revolving speed
and a torque of said input shaft but also to said oil pump directly, said torque converter having a drive plate (9)
connected to said crankshaft (8), a front cover (106) connected to said drive plate (9), an impeller shell (102)
integrally coupled to said front cover (106) and provided with an impeller (102a) which generates a centrifugal
hydraulic pressure, a turbine runner (4) disposed in front of said impeller (102a) to receive said centrifugal hydraulic
pressure and connected to said input shaft (13), and a stator (5) disposed between said impeller shell (102) and
said turbine runner (4), and said front cover (106) and said impeller shell (102) forming an outer hull containing
said turbine runner (4), characterized in that:
said front cover (106) includes a flanged portion (107) integrally formed to an outer periphery of said front
cover by a plastic working of said front cover in order to fasten said front cover with said drive plate (9), and
a pilot boss portion (132) integrally formed at a center of said front cover (106) by a plastic working of said
front cover in order to cover an end of said input shaft (13),
40
said outer hull includes a ring gear (110) for starting the engine integrally formed to an outer periphery of said
outer hull by a plastic working of said outer hull,
said flanged portion (107) includes a lamination of a cover material of said front cover (106) so as to increase
the thickness of said flanged portion (107), and
45
said ring gear (110) is an increased thickness portion of said outer hull.
2.
50
55
The torque converter according to claim 1, characterized in that:
said torque converter further comprises a fluid-tight brazing or coating layer provided at a mating portion of
the lamination of said flanged portion (107) which is in communication with a screw hole portion (107a) that
is provided in said flanged portion (107).
3.
The torque converter according to claim 1, characterized in that:
said ring gear (110) for the starter is integrally formed to a front portion of the outer periphery of said impeller
shell (102).
8
EP 0 997 666 B1
4.
The torque converter according to claim 1, characterized in that:
said ring gear (110) for starting the engine is integrally formed to a rear portion of the outer periphery of said
front cover (106).
5
5.
The torque converter according to claim 1, characterized in that:
said front cover (106) and said impeller shell (102) each comprises a deformed steel plate having the following
composition
10
0.2-0.6 weight percent carbon
0.01-0.1 weight percent silicon
0.05-0.5 weight percent manganese
15
0.01-0.1 weight percent titanium
0.001-0.01 weight percent boron
20
remainder weight percent iron.
6.
said torque converter further comprises an oil pump driving shaft (120) axially protruding from said impeller
shell (102), and said oil pump driving shaft (120) includes at least a first induction hardened portion that is to
be fitted to an inner rotor (21) of said oil pump (18) and a second induction hardened portion that is to be
supported relative to a housing of said oil pump via a bush (22).
25
30
The torque converter according to claim 5, characterized in that:
7.
The torque converter according to claim 5, characterized in that:
said torque converter further comprises an oil pump driving shaft (120) axially protruding from said impeller
shell (102), and said oil pump driving shaft includes at least an induction hardened inner surface that is to
oppose a disc surface of said stator via a thrust bearing.
35
8.
said front cover (106) includes at least one of an induction hardened inner surface of a disc portion, an induction
hardened surface that is to oppose a turbine hub (12) via a thrust bearing, and an induction hardened central
protrusion.
40
9.
45
The torque converter according to claim 1, characterized in that:
The torque converter according to claim 1, characterized in that:
said torque converter further comprises a sleeve-like oil pump driving shaft (120) that is formed integrally with
said impeller shell via plastic working.
10. The torque converter according to claim 1, characterized in that:
50
55
said flanged portion (107) and said ring gear (110) are to perform an inertia function and a power transmission
function.
11. A method manufacturing a front cover of a torque converter provided between a crankshaft (8) of an engine and
an oil pump (18) mounted on an input shaft (13), for transmitting a driving power of said engine not only to said
input shaft while changing a revolving speed and a torque of said input shaft but also to said oil pump directly, said
torque converter having a drive plate (9) connected to said crankshaft (8), said front cover (106) connected to said
drive plate (9), an impeller shell (102) integrally coupled to said front cover (106) and provided with an impeller
(102a) which generates a centrifugal hydraulic pressure, a turbine runner (4) disposed in front of said impeller
(102a) to receive said centrifugal hydraulic pressure and connected to said input shaft (13), and a stator (5) dis-
9
EP 0 997 666 B1
posed between said impeller shell (102) and said turbine runner (4), and said front cover (106) and said impeller
shell (102) forming an outer hull in which is to be contained said turbine runner (4), characterized by steps of:
blanking a disc-shaped metal plate (41),
5
forming a swelled portion (42) at a center of said disc-shaped metal plate (41) by performing a press working,
forming a boss portion (45) by pressing said swelled portion using a mold (43) and a roller (44), said boss
portion having a first wall portion perpendicular to said disc-shaped metal plate,
10
forming a cylindrical portion (46) to an outer periphery of said disc-shape metal plate through a press working,
said cylindrical portion (46) having a second wall portion perpendicular to said disc-shaped metal plate,
forming a protrusion (48) constituting a flanged portion (107) by bulging outwardly said second wall,
15
pressing said cylindrical portion in an axial direction thereof so as to crimp said protrusion (48) to be provided
with an Ω-shape in section,
shaping the outer shape of said protrusion (48) by a roller (49),
20
pressing and folding said protrusion (48) so as to forming said flanged portion into a lamination increasing the
thickness of said flanged portion (107),
flattening an outer periphery of said flanged portion (107) by a roller (51),
25
drilling a plurality screw holes (107a) in said flanged portion, and,
providing a fluid-tight brazing or coating layer at a mating portion of the lamination of said flanged portion which
is in communication with said screw holes (107a).
30
12. The method according to claim 11, characterized in that:
35
said method further comprises providing a ring gear (110) with an increased thickness for starting the engine,
the providing of said ring gear comprises integrally forming said ring gear with a rear portion of an outer periphery of said front cover (106) by performing a plastic working operation.
13. The method according to claim 11, characterized in that:
said disc-shaped metal plate (41) is a steel plate having the following composition
40
0.2-0.6 weight percent carbon
0.01-0.1 weight percent silicon
45
0.05-0.5 weight percent manganese
0.01-0.1 weight percent titanium
0.001-0.01 weight percent boron
50
remainder weight percent iron.
14. The method according to claim 13, characterized in that:
55
said method further comprises at least one of induction hardening a inner surface of a disc portion of said front
cover (106), induction hardening a surface of said front cover (106) that is oppose a turbine hub via a thrust
bearing, and induction hardening a central protrusion of said front cover (106).
10
EP 0 997 666 B1
15. The method according to claim 12, characterized in that:
said flanged portion (107) and said ring gear (110) are to perform an inertia function and a power transmission
function.
5
10
15
20
25
16. A method manufacturing an impeller shell of a torque converter provided between a crankshaft (8) of an engine
and an oil pump (18) mounted on an input shaft (13), for transmitting a driving power of said engine not only to
said input shaft while changing a revolving speed and a torque of said input shaft but also to said oil pump directly,
said torque converter having a drive plate (9) connected to said crankshaft (8), said front cover (106) connected
to said drive plate (9), an impeller shell (102) integrally coupled to said front cover (106) and provided with an
impeller (102a) which generates a centrifugal hydraulic pressure, a turbine runner (4) disposed in front of said
impeller (102a) to receive said centrifugal hydraulic pressure and connected to said input shaft (13), and a stator
(5) disposed between said impeller shell (102a) and said turbine runner (4), and said front cover (106) and said
impeller shell (102) forming an outer hull in which is to be contained said turbine runner (4), characterized by
steps of:
blanking a disc-shaped metal plate (55),
shaping said disc-shaped metal plate (55) so as to have a semi-spherical shape through a press working,
forming a swelled portion (56) to the central portion of said disc-shaped metal plate (55) through a press
working,
forming a sleeve-like oil pump driving shaft (120) by pressing said swelled portion (56) and cutting an end
thereof, said sleeve-like oil driving pump shaft having wall portion perpendicular to said disc-shaped metal
plate (55),
bulging a middle portion of said disc-shaped metal plate between said an outer periphery thereof and said oil
pump driving shaft in a direction perpendicular to said disc-shaped metal plate so as to form an impeller shell
with a flanged portion (57),
thickening said flanged portion (57) by a roll spinning so as to form a thickened portion, and
forming a ring gear (110) for starting the engine to said thickened portion through a rolling method or machining
work.
30
17. The method according to claim 16, characterized in that:
said disc-shaped metal plate (55) is a steel plate having the following composition
35
0.2-0.6 weight percent carbon
0.01-0.1 weight percent silicon
0.05-0.5 weight percent manganese
40
0.01-0.1 weight percent titanium
0.001-0.01 weight percent boron
45
remainder weight percent iron.
18. The method according to claim 17, characterized in that:
50
said method further comprises induction hardening at least a first portion of said oil pump driving shaft (120)
that is to be fitted to an inner rotor of an oil pump and induction a second portion of said oil pump driving shaft
that is to be supported relative to a housing of the oil pump.
19. The method according to claim 17, characterized in that:
55
said method further comprises induction hardening at least an inner surface of said oil pump driving shaft
(120) that is to oppose a disc surface of said stator via a thrust bearing.
20. The method according to claim 16, characterized in that:
11
EP 0 997 666 B1
said ring gear (110) is to perform an inertia function and a power transmission function.
Patentansprüche
5
1.
Drehmomentwandler, angeordnet zwischen einer Kurbelwelle (8) eines Verbrennungsmotors und einer an einer
Eingangswelle (13) befestigten Ölpumpe (18), um eine Antriebskraft des Verbrennungsmotors nicht nur zu der
Eingangswelle zu übertragen, während deren Drehzahl und Drehmoment geändert werden, sondern auch direkt
zu der Ölpumpe, wobei der Drehmomentwandler aufweist: eine Mitnehmerscheibe (9), die mit der Kurbelwelle (8)
verbunden ist; ein Frontgehäuse (106), das mit der Mitnehmerscheibe (9) verbunden ist; ein Schaufelradgehäuse
(102), das mit dem Frontgehäuse (106) integriert und mit einem Schaufelrad (102a) versehen ist, das einen zentrifugalen hydraulischen Druck erzeugt; ein Turbinenrad (4), das zur Aufnahme des zentrifugalen hydraulischen
Drucks vor dem Schaufelrad (102a) angeordnet und mit der Eingangswelle (13) verbunden ist; und ein Leitrad (5),
das zwischen dem Schaufelradgehäuse (102) und dem Turbinenrad (4) angeordnet ist; und wobei das Frontgehäuse (106) und das Schaufelradgehäuse (102) ein Außengehäuse bilden, das das Turbinenrad (4) enthält;
dadurch gekennzeichnet, dass
das Frontgehäuse (106) einschließt: einen Flanschteil (107), der in einen Außenrand des Frontgehäuses durch
plastische Umformung desselben integriert ist, um das Frontgehäuse an der Mitnehmerscheibe (9) zu befestigen;
und einen vorspringenden Führungsteil (132), der in eine Mitte des Frontgehäuses (106) durch plastische Umformung desselben integriert ist, um ein Ende der Eingangswelle (13) abzudecken;
das Außengehäuse einen Zahnkranz (110) für das Starten des Verbrennungsmotors einschließt, wobei der Zahnkranz in einen Außenrand des Außengehäuses durch plastische Umformung desselben integriert ist;
der Flanschteil (107) eine Dopplung eines Abdeckmaterials des Frontgehäuses (106) einschließt, um so die Dicke
des Flanschteils (107) zu vergrößern; und
der Zahnkranz (110) ein Teil des Außengehäuses ist, der eine vergrößerte Dicke aufweist.
2.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass der Drehmomentwandler ferner eine
flüssigkeitsdichte Hartlöt- oder Schutzschicht umfasst, die an einem passenden Teil der Dopplung des Flanschteils
(107) vorgesehen ist, wobei der passende Teil in Verbindung mit einem Schraubenlochteil (107a) steht, der in dem
Flanschteil (107) vorgesehen ist.
3.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass der Zahnkranz (110) für den Anlasser in
einen vorderen Teil des Außenrands des Schaufelradgehäuses (102) integriert ist.
4.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass der Zahnkranz (110) für das Starten des
Verbrennungsmotors in einen hinteren Teil des Außenrands des Frontgehäuses (106) integriert ist.
5.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass das Frontgehäuse (106) und das Schaufelradgehäuse (102) jeweils eine verformte Stahlplatte umfassen, die die folgende Zusammensetzung hat:
10
15
20
25
30
35
40
0,2-0,6 Gewichtsprozent Kohlenstoff;
0,01-0,1 Gewichtsprozent Silicium;
0,05-0,5 Gewichtsprozent Mangan;
0,01-0,1 Gewichtsprozent Titan;
0,001-0,01 Gewichtsprozent Bor; und
restliche Gewichtsprozent Eisen.
45
6.
Drehmomentwandler nach Anspruch 5, dadurch gekennzeichnet, dass der Drehmomentwandler ferner eine
Ölpumpenantriebswelle (120) umfasst, die axial von dem Schaufelradgehäuse (102) vorspringt; und dass die Ölpumpenantriebswelle (120) mindestens einschließt: einen ersten induktionsgehärteten Teil, der an einem Innenrotor (21) der Ölpumpe (18) zu befestigen ist; und einen zweiten induktionsgehärteten Teil, der relativ zu einem
Gehäuse der Ölpumpe durch eine Buchse (22) zu stützen ist.
7.
Drehmomentwandler nach Anspruch 5, dadurch gekennzeichnet, dass der Drehmomentwandler ferner eine
Ölpumpenantriebswelle (120) umfasst, die axial von dem Schaufelradgehäuse (102) vorspringt; und dass die Ölpumpenantriebswelle mindestens eine induktionsgehärtete Innenfläche einschließt, die über ein Drucklager einer
Scheibenfläche des Leitrads gegenüberliegen muss.
50
55
12
EP 0 997 666 B1
8.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass das Frontgehäuse (106) mindestens
eine von einer induktionsgehärteten Innenfläche eines Scheibenteils, einer induktionsgehärteten Oberfläche, die
über ein Drucklager einer Turbinennabe (12) gegenüberliegen muss, und einer induktionsgehärteten mittigen Vorwölbung einschließt.
9.
Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass der Drehmomentwandler ferner eine
hülsenähnliche Ölpumpenantriebswelle (120) umfasst, die durch plastische Umformung in das Schaufelradgehäuse integriert ist.
5
10
15
20
25
30
35
40
10. Drehmomentwandler nach Anspruch 1, dadurch gekennzeichnet, dass der Flanschteil (107) und der Zahnkranz
(110) eine Trägheitsfunktion und eine Kraftübertragungsfunktion erfüllen sollen.
11. Verfahren zur Herstellung eines Frontgehäuses eines Drehmomentwandlers, der zwischen einer Kurbelwelle (8)
eines Verbrennungsmotors und einer an einer Eingangswelle (13) befestigten Ölpumpe (18) angeordnet ist, um
eine Antriebskraft des Verbrennungsmotors nicht nur zu der Eingangswelle zu übertragen, während deren Drehzahl und Drehmoment geändert werden, sondern auch direkt zu der Ölpumpe, wobei der Drehmomentwandler
aufweist: eine Mitnehmerscheibe (9), die mit der Kurbelwelle (8) verbunden ist; das Frontgehäuse (106), das mit
der Mitnehmerscheibe (9) verbunden ist; ein Schaufelradgehäuse (102), das mit dem Frontgehäuse (106) integriert
und mit einem Schaufelrad (102a) versehen ist, das einen zentrifugalen hydraulischen Druck erzeugt; ein Turbinenrad (4), das zur Aufnahme des zentrifugalen hydraulischen Drucks vor dem Schaufelrad (102a) angeordnet
und mit der Eingangswelle (13) verbunden ist; und ein Leitrad (5), das zwischen dem Schaufelradgehäuse (102)
und dem Turbinenrad (4) angeordnet ist; und wobei das Frontgehäuse (106) und das Schaufelradgehäuse (102)
ein Außengehäuse bilden, in dem das Turbinenrad (4) enthalten sein soll;
gekennzeichnet durch die Schritte zum
Ausstanzen einer scheibenförmigen Metallplatte (41);
Ausbilden eines aufgewölbten Teils (42) an einer Mitte der scheibenförmigen Metallplatte (41) durch Pressformung;
Ausbilden eines vorspringenden Teils (45) durch Drücken des aufgewölbten Teils mit einer Pressform (43) und
einer Walze (44), wobei der vorspringende Teil einen ersten Wandteil aufweist, der senkrecht zur scheibenförmigen
Metallplatte angeordnet ist;
Ausbilden eines zylindrischen Teils (46) eines Außenrands der scheibenförmigen Metallplatte durch Pressformung, wobei der zylindrische Teil (46) einen zweiten Wandteil aufweist, der senkrecht zur scheibenförmigen Metallplatte angeordnet ist;
Ausbilden einer Vorwölbung (48), die einen Flanschteil (107) bildet, indem die zweite Wand nach außen aufgewölbt
wird;
Drücken des zylindrischen Teils in dessen axialer Richtung, um die Vorwölbung (48) so zu krümmen, dass sie im
Querschnitt eine Ω-Form aufweist;
Formen der Außenform der Vorwölbung (48) mit einer Walze (49);
Drücken und Abkanten der Vorwölbung (48), um so den Flanschteil in einer Dopplung auszubilden, wobei die
Dicke des Flanschteils (107) vergrößert wird;
Abflachen des Außenrands des Flanschteils (107) mit einer Walze (51);
Einbohren mehrerer Schraubenlöcher (107a) in den Flanschteil; und
Bereitstellen einer flüssigkeitsdichten Hartlöt- oder Schutzschicht an einem passenden Teil der Dopplung des
Flanschteils, wobei der passende Teil in Verbindung mit den Schraubenlöchern (107a) steht.
45
12. Verfahren nach Anspruch 11, dadurch gekennzeichnet, dass das Verfahren ferner die Bereitstellung eines Zahnkranzes (110) mit einer vergrößerten Dicke zum Starten des Verbrennungsmotors umfasst, wobei die Bereitstellung
des Zahnkranzes das Ausbilden eines in einen hinteren Teil eines Außenrands des Frontgehäuses (106) integrierten Zahnrads umfasst, indem ein plastischer Umformvorgang durchgeführt wird.
50
13. Verfahren nach Anspruch 11, dadurch gekennzeichnet, dass die scheibenförmige Metallplatte (41) eine Stahlplatte ist, die die folgende Zusammensetzung hat:
55
0,2-0,6 Gewichtsprozent Kohlenstoff;
0,01-0,1 Gewichtsprozent Silicium;
0,05-0,5 Gewichtsprozent Mangan;
0,01-0,1 Gewichtsprozent Titan;
0,001-0,01 Gewichtsprozent Bor; und
13
EP 0 997 666 B1
restliche Gewichtsprozent Eisen.
5
14. Verfahren nach Anspruch 13, dadurch gekennzeichnet, dass das Verfahren mindestens eine von einer Induktionshärtung einer Innenfläche eines Scheibenteils des Frontgehäuses (106), einer Induktionshärtung einer Oberfläche des Frontgehäuses (106), die über ein Drucklager einer Turbinennabe gegenüberliegen muss, und einer
Induktionshärtung einer mittigen Vorwölbung des Frontgehäuses (106) umfasst.
15. Verfahren nach Anspruch 12, dadurch gekennzeichnet, dass der Flanschteil (107) und der Zahnkranz (110) eine
Trägheitsfunktion und eine Kraftübertragungsfunktion erfüllen sollen.
10
15
20
25
30
35
16. Verfahren zur Herstellung eines Schaufelradgehäuses eines Drehmomentwandlers, der zwischen einer Kurbelwelle (8) eines Verbrennungsmotors und einer an einer Eingangswelle (13) befestigten Ölpumpe (18) angeordnet
ist, um eine Antriebskraft des Verbrennungsmotors nicht nur zu der Eingangswelle zu übertragen, während deren
Drehzahl und Drehmoment geändert werden, sondern auch direkt zu der Ölpumpe, wobei der Drehmomentwandler
aufweist: eine Mitnehmerscheibe (9), die mit der Kurbelwelle (8) verbunden ist; das Frontgehäuse (106), das mit
der Mitnehmerscheibe (9) verbunden ist; ein Schaufelradgehäuse (102), das mit dem Frontgehäuse (106) integriert
und mit einem Schaufelrad (102a) versehen ist, das einen zentrifugalen hydraulischen Druck erzeugt; ein Turbinenrad (4), das zur Aufnahme des zentrifugalen hydraulischen Drucks vor dem Schaufelrad (102a) angeordnet
und mit der Eingangswelle (13) verbunden ist; und ein Leitrad (5), das zwischen dem Schaufelradgehäuse (102)
und dem Turbinenrad (4) angeordnet ist; und wobei das Frontgehäuse (106) und das Schaufelradgehäuse (102)
ein Außengehäuse bilden, in dem das Turbinenrad (4) enthalten sein soll;
gekennzeichnet durch die Schritte zum
Ausstanzen einer scheibenförmigen Metallplatte (55);
Formen der scheibenförmigen Metallplatte (55), um so durch Pressformung eine Halbkugelform zu erhalten;
Ausbilden eines aufgewölbten Teils (56) an dem Mittelteil der scheibenförmigen Metallplatte (55) durch Pressformung;
Ausbilden einer hülsenähnlichen Ölpumpenantriebswelle (120) durch Drücken des aufgewölbten Teils (56) und
Abschneiden eines Endes desselben, wobei die hülsenähnliche Ölpumpenantriebswelle einen Wandteil aufweist,
der senkrecht zu der scheibenförmigen Metallplatte (55) angeordnet ist;
Aufwölben eines Mittelteils der scheibenförmigen Metallplatte zwischen deren Außenrand und der Ölpumpenantriebswelle in einer Richtung, die senkrecht zu der scheibenförmigen Metallplatte steht, um so ein Schaufelradgehäuse mit einem Flanschteil (57) auszubilden;
Verdicken des Flanschteils (57) durch Drückwalzen, um so einen verdickten Teil auszubilden; und
Ausbilden eines zum Starten des Verbrennungsmotors dienenden Zahnkranzes (110) an dem verdickten Teil durch
ein Walzverfahren oder spanende Bearbeitung.
17. Verfahren nach Anspruch 16, dadurch gekennzeichnet, dass die scheibenförmige Metallplatte (55) eine Stahlplatte ist, die die folgende Zusammensetzung hat:
40
45
50
0,2-0,6 Gewichtsprozent Kohlenstoff;
0,01-0,1 Gewichtsprozent Silicium;
0,05-0,5 Gewichtsprozent Mangan;
0,01-0,1 Gewichtsprozent Titan;
0,001-0,01 Gewichtsprozent Bor; und
restliche Gewichtsprozent Eisen.
18. Verfahren nach Anspruch 17, dadurch gekennzeichnet, dass das Verfahren ferner umfasst: eine Induktionshärtung von mindestens einem ersten Teil der Ölpumpenantriebswelle (120), der an einem Innenrotor einer Ölpumpe
zu befestigen ist; und eine Induktionshärtung eines zweiten Teils der Ölpumpenantriebswelle, der relativ zu einem
Gehäuse der Ölpumpe zu stützen ist.
19. Verfahren nach Anspruch 17, dadurch gekennzeichnet, dass das Verfahren ferner eine Induktionshärtung zumindest einer zu der Ölpumpenantriebswelle (120) gehörenden Innenfläche umfasst, die über ein Drucklager einer
Scheibenfläche des Leitrads gegenüberliegen soll.
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20. Verfahren nach Anspruch 16, dadurch gekennzeichnet, dass der Zahnkranz (110) eine Trägheitsfunktion und
eine Kraftübertragungsfunktion erfüllen soll.
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Revendications
1.
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ledit couvercle avant (106) comprend une portion formant bride (107) formée d'un seul tenant sur une périphérie extérieure dudit couvercle avant par un façonnage plastique dudit couvercle avant afin de fixer ledit
couvercle avant avec ladite plaque d'entraînement (9), et une portion formant embout (132) formée d'un seul
tenant au centre dudit couvercle avant (106) par un façonnage plastique dudit couvercle avant afin de recouvrir
une extrémité dudit arbre d'entrée (13),
ladite coque extérieure comprend une couronne dentée (110) pour démarrer le moteur, formée d'un seul tenant
sur une périphérie extérieure de ladite coque extérieure par un façonnage plastique de ladite coque extérieure,
ladite portion formant bride (107) comprend une doublure d'un matériau de couvercle dudit couvercle avant
(106) de façon à augmenter l'épaisseur de ladite portion formant bride (107), et
ladite couronne dentée (110) est une portion d'épaisseur accrue de ladite coque extérieure.
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Convertisseur de couple pourvu entre un vilebrequin (8) d'un moteur et une pompe à huilé (18) montée sur un
arbre d'entrée (13), pour transmettre une force motrice dudit moteur non seulement audit arbre d'entrée tout en
changeant une vitesse de révolution et un couple dudit arbre d'entrée, mais aussi directement à ladite pompe à
huile, ledit convertisseur de couple comportant une plaque d'entraînement (9) raccordée audit vilebrequin (8), un
couvercle avant (106) raccordé à ladite plaque d'entraînement (9), une enveloppe d'impulseur (102) couplée d'un
seul tenant audit couvercle avant (106) et munie d'un impulseur (102a) qui génère une pression hydraulique centrifuge, une roue mobile de turbine (4) disposée devant ledit impulseur (102a) pour recevoir ladite pression hydraulique centrifuge et raccordée audit arbre d'entrée (13), et un stator (5) disposé entre ladite enveloppe d'impulseur (102) et ladite roue mobile de turbine (4), et ledit couvercle avant (106) et ladite enveloppe d'impulseur
(102) formant une coque extérieure contenant ladite roue mobile de turbine (4), caractérisé en ce que :
2.
Convertisseur de couple selon la revendication 1, caractérisé en ce que :
ledit convertisseur de couple comprend en outre une couche de brasage ou de revêtement étanche aux fluides
prévue au niveau d'une portion conjuguée de la doublure de ladite portion formant bride (107), qui est en
communication avec une portion formant trou de vis (107a) prévue dans ladite portion formant bride (107).
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3.
Convertisseur de couple selon la revendication 1, caractérisé en ce que :
ladite couronne dentée (110) pour le démarreur est formée d'un seul tenant sur une portion avant de la périphérie extérieure de ladite enveloppe d'impulseur (102).
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4.
Convertisseur de couple selon la revendication 1, caractérisé en ce que :
ladite couronne dentée (110) pour démarrer le moteur est formée d'un seul tenant sur une portion arrière de
la périphérie extérieure dudit couvercle avant (106).
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5.
ledit couvercle avant (106) et ladite enveloppe d'impulseur (102) comprennent chacun une plaque d'acier
déformée ayant la composition suivante
entre 0,2 et 0,6 pour-cent en poids de carbone,
entre 0,01 et 0,1 pour-cent en poids de silicium,
entre 0,05 et 0,5 pour-cent en poids de manganèse,
entre 0,01 et 0,1 pour-cent en poids de titane,
entre 0,001 et 0,01 pour-cent en poids de bore,
le pourcentage en poids restant de fer.
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6.
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Convertisseur de couple selon la revendication 1, caractérisé en ce que :
Convertisseur de couple selon la revendication 5, caractérisé en ce que :
ledit convertisseur de couple comprend en outre un arbre d'entraînement de pompe à huile (120) faisant saillie
axialement de ladite enveloppe d'impulseur (102), et ledit arbre d'entraînement de pompe à huile (120) comprend au moins une première portion trempée par induction, qui doit être installée sur un rotor intérieur (21)
de ladite pompe à huile (18) et une deuxième portion trempée par induction qui doit être supportée par rapport
à un carter de ladite pompe à huile par l'intermédiaire d'un coussinet (22).
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7.
Convertisseur de couple selon la revendication 5, caractérisé en ce que :
ledit convertisseur de couple comprend en outre un arbre d'entraînement de pompe à huile (120) faisant saillie
axialement de ladite enveloppe d'impulseur (102), et ledit arbre d'entraînement de pompe à huile comprend
au moins une surface intérieure trempée par induction qui doit s'opposer à une surface en forme de disque
dudit stator par l'intermédiaire d'un palier de butée.
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8.
Convertisseur de couple selon la revendication 1, caractérisé en ce que :
ledit couvercle avant (106) comprend au moins l'une d'une surface intérieure d'une portion de disque trempée
par induction, d'une surface trempée par induction qui doit s'opposer à un moyeu de turbine (12) par l'intermédiaire d'un palier de butée, et d'une saillie centrale trempée par induction.
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9.
Convertisseur de couple selon la revendication 1, caractérisé en ce que :
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ledit convertisseur de couple comprend en outre un arbre d'entraînement de pompe à huile (120) en forme
de manchon qui est formé d'un seul tenant avec ladite enveloppe d'impulseur par l'intermédiaire d'un façonnage plastique.
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10. Convertisseur de couple selon la revendication 1, caractérisé en ce que :
ladite portion formant bride (107) et ladite couronne dentée (110) doivent exécuter une fonction d'inertie et
une fonction de transmission de puissance.
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11. Procédé de fabrication d'un couvercle avant d'un convertisseur de couple pourvu entre un vilebrequin (8) d'un
moteur et une pompe à huile (18) montée sur un arbre d'entrée (13), pour transmettre une force motrice dudit
moteur non seulement audit arbre d'entrée tout en changeant une vitesse de révolution et un couple dudit arbre
d'entrée, mais aussi directement à ladite pompe à huile, ledit convertisseur de couple comportant une plaque
d'entraînement (9) raccordée audit vilebrequin (8), un couvercle avant (106) raccordé à ladite plaque d'entraînement (9), une enveloppe d'ïmpulseur (102) couplée d'un seul tenant audit couvercle avant (106) et munie d'un
impulseur (102a) qui génère une pression hydraulique centrifuge, une roue mobile de turbine (4) disposée devant
ledit impulseur (102a) pour recevoir ladite pression hydraulique centrifuge et raccordée audit arbre d'entrée (13),
et un stator (5) disposé entre ladite enveloppe d'impulseur (102) et ladite roue mobile de turbine (4), ledit couvercle
avant (106) et ladite enveloppe d'impulseur (102) formant une coque extérieure dans laquelle doit être contenue
ladite roue mobile de turbine (4), caractérisé par les étapes consistant à :
découper une plaque métallique en forme de disque (41),
former une portion renflée (42) au centre de ladite plaque métallique en forme de disque (41) en effectuant
un travail à la presse,
former une portion formant bosse (45) en pressant ladite portion renflée au moyen d'un moule (43) et d'un
galet (44), ladite portion formant bosse possédant une première portion formant paroi perpendiculaire à ladite
plaque métallique en forme de disque,
former une portion cylindrique (46) sur une périphérie extérieure de ladite plaque métallique en forme de
disque par l'intermédiaire d'un travail à la presse, ladite portion cylindrique (46) possédant une deuxième
portion formant paroi perpendiculaire à ladite plaque métallique en forme de disque,
former une saillie (48) constituant une portion formant bride (107) en bombant vers l'extérieur ladite deuxième
paroi,
presser ladite portion cylindrique dans sa direction axiale de façon à sertir ladite saillie (48) devant présenter
une section en forme de Ω,
profiler la forme extérieure de ladite saillie (48) par un galet (49),
presser et plier ladite saillie (48) de façon à former ladite portion formant bride en une doublure augmentant
l'épaisseur de ladite portion formant bride (107),
aplatir une périphérie extérieure de ladite portion formant bride (107) par un galet (51),
forer une pluralité de trous de vis (107a) dans ladite portion formant bride, et
prévoir une couche de brasage ou de revêtement étanche aux fluides au niveau d'une portion conjuguée de
la doublure de ladite portion formant bride qui est en communication avec lesdits trous de vis (107a).
12. Procédé selon la revendication 11, caractérisé en ce que :
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ledit procédé comprend en outre l'étape consistant à prévoir une couronne dentée (110) d'épaisseur accrue
pour démarrer le moteur, la prévision de ladite couronne comprenant l'étape consistant à former d'un seul
tenant ladite couronne avec une portion arrière d'une périphérie extérieure dudit couvercle avant (106) en
exécutant une opération de façonnage plastique.
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13. Procédé selon la revendication 11, caractérisé en ce que :
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ladite plaque métallique en forme de disque (41) est une plaque d'acier ayant la composition suivante
entre 0,2 et 0,6 pour-cent en poids de carbone,
entre 0,01 et 0,1 pour-cent en poids de silicium,
entre 0,05 et 0,5 pour-cent en poids de manganèse,
entre 0,01 et 0,1 pour-cent en poids de titane,
entre 0,001 et 0,01 pour-cent en poids de bore,
le pourcentage en poids restant de fer.
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14. Procédé selon la revendication 13, caractérisé en ce que :
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ledit procédé comprend en outre au moins l'une des étapes consistant à tremper par induction une surface
intérieure d'une portion en forme de disque dudit couvercle avant (106), tremper par induction une surface
dudit couvercle avant (106) qui doit s'opposer à un moyeu de turbine par l'intermédiaire d'un palier de butée,
et tremper par induction une saillie centrale dudit couvercle avant (106).
15. Procédé selon la revendication 12, caractérisé en ce que :
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ladite portion formant bride (107) et ladite couronne dentée (110) doivent exécuter une fonction d'inertie et
une fonction de transmission de puissance.
16. Procédé de fabrication d'une enveloppe d'impulseur d'un convertisseur de couple pourvu entre un vilebrequin (8)
d'un moteur et une pompe à huile (18) montée sur un arbre d'entrée (13), pour transmettre une force motrice dudit
moteur non seulement audit arbre d'entrée tout en changeant une vitesse de révolution et un couple dudit arbre
d'entrée, mais aussi directement à ladite pompe à huile, ledit convertisseur de couple comportant une plaque
d'entraînement (9) raccordée audit vilebrequin (8), un couvercle avant (106) raccordé à ladite plaque d'entraînement (9), une enveloppe d'impulseur (102) couplée d'un seul tenant audit couvercle avant (106) et munie d'un
impulseur (102a) qui génère une pression hydraulique centrifuge, une roue mobile de turbine (4) disposée devant
ledit impulseur (102a) pour recevoir ladite pression hydraulique centrifuge et raccordée audit arbre d'entrée (13),
et un stator (5) disposé entre ladite enveloppe d'impulseur (102a) et ladite roue mobile de turbine (4), ledit couvercle
avant (106) et ladite enveloppe d'impulseur (102) formant une coque extérieure dans laquelle il est prévu de contenir ladite roue mobile de turbine (4), caractérisé par les étapes consistant à :
découper une plaque métallique en forme de disque (55),
profiler ladite plaque métallique en forme de disque (55) de façon à présenter une forme semi-sphérique, par
l'intermédiaire d'un travail à la presse,
former une portion renflée (56) dans la portion centrale de ladite plaque métallique en forme de disque (55),
par l'intermédiaire d'un travail à la presse,
former un arbre d'entraînement de pompe à huile en forme de manchon (120) en pressant ladite portion renflée
(56) et en coupant une extrémité de cette dernière, ledit arbre d'entraînement de pompe à huile en forme de
manchon comportant une portion formant paroi perpendiculaire à ladite plaque métallique en forme de disque
(55),
bomber une portion médiane de ladite plaque métallique en forme de disque entre ladite périphérie extérieure
de cette dernière et ledit arbre d'entraînement de pompe à huile dans une direction perpendiculaire à ladite
plaque métallique en forme de disque de façon à former une enveloppe d'impulseur comportant une portion
formant bride (57),
épaissir ladite portion formant bride (57) par fluofournage de façon à former une portion épaissie, et
former une couronne dentée (110) pour démarrer le moteur sur ladite portion épaissie par l'intermédiaire d'un
procédé de laminage ou d'un travail d'usinage.
17. Procédé selon la revendication 16, caractérisé en ce que :
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ladite plaque métallique en forme de disque (55) est une plaque d'acier ayant la composition suivante
entre 0,2 et 0,6 pour-cent en poids de carbone,
entre 0,01 et 0,1 pour-cent en poids de silicium,
entre 0,05 et 0,5 pour-cent en poids de manganèse,
entre 0,01 et 0,1 pour-cent en poids de titane,
entre 0,001 et 0,01 pour-cent en poids de bore,
le pourcentage en poids restant de fer.
18. Procédé selon la revendication 17, caractérisé en ce que :
10
ledit procédé comprend en outre les étapes consistant à tremper par induction au moins une première portion
dudit arbre d'entraînement de pompe à huile (120) qui est prévue pour être installée sur un rotor intérieur
d'une pompe à huile et tremper par induction une deuxième portion dudit arbre d'entraînement de pompe à
huile qui doit être supportée par rapport à un carter de la pompe à huile.
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19. Procédé selon la revendication 17, caractérisé en ce que :
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ledit procédé comprend en outre l'étape consistant à tremper par induction au moins une surface intérieure
dudit arbre d'entraînement de pompe à huile (120) qui doit s'opposer à une surface en forme de disque dudit
stator par l'intermédiaire d'un palier de butée.
20. Procédé selon la revendication 16, caractérisé en ce que :
ladite couronne(110) doit exécuter une fonction d'inertie et une fonction de transmission de puissance.
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50
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