JP2003343690A - Torque converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To house a group of sprags even in a narrow space between an end wall of a stator hub and a press plate without particularly increasing axial length of the stator hub and an outer race, while sufficiently ensuring axial length of the sprag and a contact part of the outer race. <P>SOLUTION: In the torque converter, a free wheel 11 interposed between the stator hub 4h and a stator shaft 12 is constituted of: the outer race 15 at the stator hub 4h side; an inner race 16 at the stator shaft 12 side; a group of sprags 17 interposed between the both races 15, 16; and a retainer 18 for retaining this group of sprags 17. The end wall 27 supporting one end of the outer race 15 and the retainer is integrally formed on the stator hub 4h and the press plate 28 is provided at the other end of the retainer 18 so as to be opposed thereto. An annular recessed part 30 accepting one end 18a of the retainer 18 is formed on the end wall 27. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque converter used in a vehicle or an industrial machine, and more particularly, to a pump impeller connected to an input shaft and an output shaft connected to the pump impeller. A turbine impeller and a stator impeller arranged between the inner peripheral portions of the pump impeller and the turbine impeller are provided, and between the stator hub of the stator impeller and the stator shaft arranged at the center thereof. The free wheel interposed is an outer race connected to a stator hub, an inner race connected to a stator shaft, an annular array of sprags interposed between the two races, and an annular array holding the sprags. The outer race and the end wall that supports one end of the retainer are integrally formed with the stator hub while the retainer is formed integrally with the stator hub. The retainer plate opposite to the other end of the burner to an improvement of a torque converter provided in the outer race.

[0002]

2. Description of the Related Art Such a torque converter is already known, for example, as disclosed in Japanese Patent Laid-Open No. 2000-130552.

[0003]

In the free wheel of such a torque converter, generally, the larger the axial length of the contact portion of each sprag with respect to both races, the greater the load capacity and the higher the durability. However, in the conventional torque converter, the sprag group is simply accommodated in the narrow space between the end wall and the pressing plate. Therefore, unless the axial length of both races is increased, the sprags are A sufficient axial length of the contact portion cannot be secured. However, in particular, an increase in the axial length of the outer race requires an increase in the axial length of the stator hub that connects the outer race to the inner peripheral surface, which is not preferable because it impairs the compactness of the stator hub.

The present invention has been made in view of the above circumstances, and it is possible to reduce the sprags and the sprags even in a narrow space between the end wall and the pressing plate without increasing the axial length of the stator hub or the outer race. An object of the present invention is to provide the torque converter that enables accommodation of the sprag group while ensuring a sufficient axial length of the contact portion of the outer race.

[0005]

In order to achieve the above object, the present invention provides a pump impeller connected to an input shaft, and a turbine impeller opposed to the pump impeller and connected to an output shaft. , A stator impeller arranged between the inner peripheral portions of the pump impeller and the turbine impeller, and interposed between a stator hub of the stator impeller and a stator shaft arranged at the center thereof. The freewheel has an outer race connected to the stator hub, an inner race connected to the stator shaft, an annular array of sprags interposed between the two races, and an annular array of holding windows for holding the sprags. An annular retainer, whose outer race and an end wall that supports one end of the retainer are integrally formed with the stator hub, and which is opposed to the other end of the retainer. The in the torque converter provided in the outer race, the said end wall, said retainer, and the first, characterized in that one end extending outside the holding window to form an annular recess for receiving.

The input shaft corresponds to the crankshaft 1 of the engine in an embodiment of the present invention described later.

According to the first feature, one end of the retainer of the freewheel is axially expanded by the amount of the one end of the retainer of the freewheel received in the annular recess of the end wall. It is possible to accommodate the sprag group having a relatively long axial length even in a narrow space between the end wall and the pressing plate, and as a result, the contact surface between the sprag group and the outer race is expanded, and accordingly By reducing the surface pressure, the load capacity of the freewheel can be increased and its durability can be improved. Therefore, it is not necessary to specifically increase the axial length of the stator hub or the outer race in order to use a free wheel having a large load capacity, which can contribute to downsizing of the stator hub and further downsizing of the torque converter. .

In addition to the first feature of the present invention, the outer race is press-fitted into the inner peripheral surface of the stator hub, and the inner peripheral surface of the outer race is subjected to finish cutting, and at the same time, the annular recess is cut into the end wall. The second feature is that it is formed.

According to the second feature, it is possible to easily form the annular recess in the end wall simultaneously with the finish cutting of the inner peripheral surface of the outer race after press fitting, and there is almost no increase in cost due to the formation. .

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below based on the embodiments of the present invention shown in the accompanying drawings.

FIG. 1 is a vertical sectional side view of a torque converter according to the present invention, FIG. 2 is an enlarged view of part 2 of FIG. 1, and FIG.
3 is a sectional view taken along the line 3 and FIG. 4 is an explanatory view of a part of the free wheel machining process.

First, referring to FIG. 1, the torque converter T
Is provided with a pump impeller 2, a turbine impeller 3 opposed to the pump impeller 2, and a stator impeller 4 arranged between the inner peripheral portions of the pump impeller 2. A circulation circuit 6 for power transmission is defined.

A side cover 5 that covers the outer surface of the turbine impeller 3 is integrally connected to the pump impeller 2 by welding. A ring gear 7 for starting is fitted and welded to the outer peripheral surface of the side cover 5.
The drive plate 8 connected to the crankshaft 1 is fixed by the bolt 9. A thrust bearing 26 is interposed between the turbine hub 3h of the turbine impeller 3 and the side cover 5.

An output shaft 10 arranged coaxially with the crankshaft 1 is arranged at the center of the torque converter T.
0 is spline-fitted to the turbine hub 3h, and is rotatably supported by the support cylinder 5a at the center of the side cover 5 via the bearing bush 23. The output shaft 10 serves as a main shaft of a multi-stage transmission (not shown).

On the outer circumference of the output shaft 10, a stator impeller 4 is provided.
A hollow cylindrical stator shaft 12 that supports the stator hub 4h of FIG. 1 via a free wheel 11 is arranged, and a bearing bush 13 that allows relative rotation between the output shaft 10 and the stator shaft 12 is interposed. . The outer end of the stator shaft 12 is non-rotatably supported by the mission case 14.

As clearly shown in FIGS. 2 and 3, the free wheel 11 includes an outer race 15 press-fitted to the inner peripheral surface of the stator hub 4h, and an inner race 16 splined to the outer circumference of the stator shaft 12. An annular array of sprags 1 interposed between these races 15 and 16
7 and 17 group, and annular retainer 18 having annular arrangement holding windows 18c and 18c for holding the sprags 17 and 17 group, and a ring spring for urging the sprags 17 and 17 group in the standing direction. It consists of 19 and retainer 1
The reference numeral 8 has flange-shaped end portions 18a, 18b that are bent outward in the radial direction outside the holding windows 18c, 18c ... The outer race 15 has a shorter axial length than the inner race 16.

The stator impeller 4 is made of a light alloy such as an Al alloy, and the outer race 15 press-fitted into the inner peripheral surface of the stator hub 4h is made of steel. This outer race 1
An end wall 27 that supports one end surface of 5 is formed integrally with the stator hub 4h, and a thrust bearing 29 is interposed between the end wall 27 and the pump hub 2h of the pump impeller 2.

As shown in FIG. 4, the inner peripheral surface of the outer race 15 is subjected to finish cutting after the outer race 15 is press-fitted into the stator hub 4h. Simultaneously with the cutting, an annular recess 30 continuous with the inner peripheral surface of the outer race 15 is formed. Is the end wall 27
Is cut into. Then, the one end portion 18a of the retainer 18 is received in the annular recess 30 (see FIG. 2).

In the stator hub 4h, the outer race 1 contacts the outer end surface of the outer race 15 and presses the other end 18b of the retainer 18 from the outside.
A pressing plate 28 fitted to the inner peripheral surface of the bearing 5 is arranged, and a thrust bearing 29 'is interposed between the pressing plate 28 and the stator hub 4h. This thrust bearing 2
9'holds the stator hub 4h in place between the pump hub 2h and the turbine hub 3h in cooperation with the thrust bearing 29. Both thrust bearings 29, 29 '
Is a pair of inner and outer thrust plates 31 and 32, and an annular array of needles 3 interposed between the thrust plates 31 and 32.
.. and a retainer 34 for holding the needles 33, 33 ... Group, and each inner thrust plate 31 is non-rotatably locked to the inner peripheral surface of the stator hub 4h and also has a pressing plate. The inner thrust plate 31 on the 28 side is also axially fixed to the stator hub 4h by a retaining ring 35.

A plurality of radially extending oil grooves 36, 37 are respectively provided on the outer surfaces of the end wall 27 and the pressing plate 28 facing the corresponding inner thrust plates 31, and these oil grooves 36, 37 are formed as described above. Through holes 38, 39 communicating with the inside of the outer race 15 radially inward of the retainer 18.
Are drilled in the end wall 27 and the pressing plate 28.

Further, the inner peripheral end portions of the end wall 27 and the pressing plate 28 are adapted to press the both end portions of the inner race 16 by their cooperation so as to prevent the axial movement thereof.

Referring again to FIG. 1, an auxiliary machine drive shaft 20 coupled to the pump impeller 2 is rotatably arranged on the outer periphery of the stator shaft 12, and the auxiliary machine drive shaft 20 causes the operating oil to be supplied to the torque converter T. The oil pump 21 for supplying the oil is driven.

The turbine impeller 3 and the side cover 5 have a clutch chamber 22 which communicates with the circulation circuit 6 at the outer peripheral portion.
The clutch chamber 22 is defined by the turbine impeller 3
Also, a lockup clutch L that can directly connect the side covers 5 is provided. That is, the clutch piston 25, which is the main constituent of the lockup clutch L, is arranged in the clutch chamber 22 so as to partition the clutch chamber 22 into an inner chamber 22a on the turbine impeller 3 side and an outer chamber 22b on the side cover 5 side. . The clutch piston 25 is axially movable between a connection position where the friction lining 25a provided on one end surface of the clutch piston 25 is pressed against the inner wall of the side cover 5 and a non-connection position where the friction lining 25a is separated from the inner wall of the side wall of the turbine hub. It is slidably supported on the outer peripheral surface of 3h.

Further, in the clutch chamber 22, a known torque damper D for connecting the clutch piston 25 and the turbine impeller 3 in a buffer manner is arranged.

A first oil passage 40 is provided at the center of the output shaft 10 so as to communicate with the outer chamber 22b of the clutch chamber 22 via the lateral hole 24 and the thrust bearing 26. A second oil passage 41 is defined between the accessory drive shaft 20 and the stator shaft 12 and communicates with the inner peripheral portion of the circulation circuit 6 through the oil grooves 36, 37 and the through holes 38, 39. The lockup control valve 42 alternately connects the first oil passage 40 and the second oil passage 41 to the discharge side of the oil pump 21 and the oil sump 43.

Next, the operation of this embodiment will be described.

In the idling or extremely low speed operation range of the engine, the lockup control valve 42 connects the first oil passage 40 to the discharge side of the oil pump 21 while connecting the second oil passage 41 to the discharge side as shown in FIG. It is controlled by an electronic control unit (not shown) so as to connect to the oil sump 43. Therefore, the output torque of the crankshaft 1 of the engine is transmitted to the drive plate 8, the side cover 5, and the pump impeller 2,
When it is rotationally driven and the oil pump 21 is also driven, the discharge working oil of the oil pump 21 flows from the lockup control valve 42 to the first oil passage 40, the lateral hole 24 and the thrust bearing 26, and the outer chamber 22b of the clutch chamber 22. , Through the inner chamber 22a in order to flow into the circulation circuit 6, and after filling the circuit 6, it moves to the second oil passage 41 through the oil grooves 36, 37 and the through holes 38, 39, and the oil from the lock-up control valve 42 Reflux to the reservoir 43. By the working oil passing through the through holes 38, 39, the sprags 17, 1 of the free wheel 11 are
7 ... The group is lubricated.

In the clutch chamber 22, the outer chamber 22b is the inner chamber 2 due to the flow of the working oil as described above.
The pressure becomes higher than 2a, and the pressure difference causes the clutch piston 25 to be pushed in the direction of being separated from the inner wall of the side cover 5, so that the lockup clutch L is in the disengaged state, and the pump impeller 2 and the turbine impeller are Three
The relative rotation of is allowed. Therefore, crankshaft 1
When the pump impeller 2 is rotationally driven from, the operating oil that fills the circulation circuit 5 circulates in the circulation circuit 5 as indicated by the arrow, thereby transmitting the rotational torque of the pump impeller 3 to the turbine impeller 4. , Drive the output shaft 10.

At this time, if the torque amplifying action is generated between the pump impeller 2 and the turbine impeller 3, the reaction force associated with the torque is borne by the stator impeller 4, and the stator impeller 4 moves to the free wheel 11. By the locking action, that is, the sprags 17, 17 ... Group so as to prevent the outer race 15 and the inner race 16 from rotating relative to each other,
By being locked between six, it is connected and fixed to the stator shaft 12.

When the torque amplifying action is completed, the stator impeller 4 reverses the direction of the torque received by the stator impeller 4, causing the freewheel 11 to idle, that is, the sprags 17, 17.
The group allows the two races 15 and 16 to rotate relative to each other, so that the races rotate in the same direction together with the pump impeller 2 and the turbine impeller 3.

When the torque converter T is in such a coupling state, the lockup control valve 42 is switched by the electronic control unit. As a result, the discharge working oil of the oil pump 21 flows into the circulation circuit 6 from the lock-up control valve 42 through the second oil passage 41, opposite to the previous time, and after filling the circuit 6, the clutch chamber 22 To the inner chamber 22a, which also fills the inner chamber 22a. On the other hand, the outer chamber 22b of the clutch chamber 22 is opened to the oil sump 43 via the first oil passage 40 and the lock-up control valve 42. Therefore, in the clutch chamber 22, the inner chamber 22a is larger than the outer chamber 22b. High pressure, clutch piston 2
5 is pressed to the side cover 5 side by the pressure difference,
The friction lining 25a is brought into pressure contact with the inner wall of the side cover 5, and the lockup clutch L is brought into the connected state. Then, the rotational torque transmitted from the crankshaft 1 to the pump impeller 2 is mechanically transmitted from the side cover 5 to the turbine impeller 3 via the clutch piston 25 and the torque damper D. The turbine impeller 4 is directly connected, the output torque of the crankshaft 1 can be efficiently transmitted to the output shaft 10, and fuel consumption can be reduced.

By the way, such a torque converter T
, The one end portion 18a of the retainer 18 of the free wheel 11 is received in the annular recess 30 formed in the end wall 27 of the stator hub 4h, so that the outer race 1
On the inner peripheral surface of 5, it is possible to axially expand the contact surface with which the sprags 17, 17 ... Group come into contact, and therefore the axial length is relatively long even in the narrow space between the end wall 27 and the pressing plate 28. Since the sprags 17, 17 ... Group can be accommodated, the contact surface between the sprags 17, 17 ... Group and the outer race 15 is enlarged, and the surface pressure is reduced accordingly, thereby increasing the load capacity of the freewheel 11, The durability can be improved. Therefore, since it is not necessary to increase the axial length of the stator hub 4h or the outer race 15 in order to use the free wheel having a large load capacity, the stator hub 4h can be made compact and the torque converter T can be made compact. You can

The annular recess 30 is formed by the outer race 1
After press-fitting 5 onto the inner peripheral surface of the stator hub 4h, finish cutting of the inner peripheral surface of the outer race 15 and end wall 27
Since the annular concave portion 30 is formed by cutting, the formation of the annular concave portion 30 can be easily performed, and there is almost no increase in cost due to the formation.

In addition, as in this embodiment, the retainer 18 of the free wheel 11 is made into a single type, so that the retainer 1
Since the annular recess 30 of the end wall 27 that receives one end of 8 can be formed as a single annular groove having a narrow groove width, the strength reduction of the end wall 27 due to the annular recess 30 can be minimized. preferable.

The present invention is not limited to the above embodiments, and various design changes can be made without departing from the scope of the invention.

[0036]

As described above, according to the first aspect of the present invention, a pump impeller connected to an input shaft, a turbine impeller opposed to the pump impeller and having an output shaft connected thereto, A stator impeller arranged between the inner peripheral portions of the pump impeller and the turbine impeller, and a free interposition between the stator hub of the stator impeller and the stator shaft arranged at the center of the stator hub. The wheel has an outer race connected to the stator hub, an inner race connected to the stator shaft, an annular array of sprags interposed between the two races, and an annular array of retaining windows for holding the sprags. The outer race and the end wall that supports one end of the retainer are integrally formed with the stator hub, while the outer retainer plate is opposite to the other end of the retainer. In the torque converter provided on the base, the end wall is formed with an annular recess for receiving one end of the retainer extending outside the holding window. Therefore, one end of the retainer of the freewheel is formed in the annular recess of the end wall. The contact surface of the sprag group on the inner peripheral surface of the outer race can be expanded in the axial direction by the amount received, and the sprag group having a relatively long axial length can be provided even in the narrow space between the end wall and the pressing plate. As a result, the contact surface between the sprag group and the outer race is expanded, and the contact pressure is reduced accordingly, increasing the load capacity of the freewheel,
The durability can be improved. Therefore, it is not necessary to specifically increase the axial length of the stator hub or the outer race in order to use a free wheel having a large load capacity, which can contribute to downsizing of the stator hub and further downsizing of the torque converter. .

Further, according to the second feature of the present invention, the outer race is press-fitted into the inner peripheral surface of the stator hub, and at the same time when the inner peripheral surface of the outer race is finish-cut, the annular recess is formed in the end wall by cutting. Therefore, the annular recess can be easily formed in the end wall at the same time as the finish cutting of the inner peripheral surface of the outer race after the press fitting, and the cost is hardly increased by the formation.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view of a torque converter according to the present invention.

FIG. 2 is an enlarged view of part 2 of FIG.

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is an explanatory view of a part of a free wheel processing step.

[Explanation of symbols]

T ... Torque converter 1 ... Input shaft (engine crankshaft) 2 ... Pump impeller 3 ... Turbine impeller 4 ... Stator impeller 10: Output shaft 11-Freewheel 12: Stator shaft 15-Outer race 16: Inner race 17: Sprag 18 Retainer 18a ... One end of retainer 18b .... other end of retainer 18c ··· Holding window 27: End wall of outer race 28 ... Pressing plate 30 ... Annular recess

Claims (2)

[Claims] 1. A pump impeller (2) coupled to an input shaft (1), and a turbine impeller (3) opposite to the pump impeller (2) and coupled to an output shaft (10), The stator impeller (4) is arranged between the inner peripheral portions of the pump impeller (2) and the turbine impeller (3), and the stator hub (4h) of the stator impeller (4) and its central portion. A free wheel (11) interposed between the stator shaft (12) and the outer race (15) coupled to the stator hub (4h) and the stator shaft (12).
Inner races (16) that are joined to
5,16) an annular array of sprags (17)
And an end wall for supporting one end of the outer race (15) and the retainer (18), the retainer (18) having an annular retainer (18) having a group of retaining windows (18c) for retaining the group of sprags (17) (27) is integrally formed with the stator hub (4h), and the pressing plate (28) facing the other end of the retainer (18) is provided with an outer race (15).
The torque converter provided in the end wall (27)
A torque converter characterized in that an annular recess (30) for receiving one end (18a) of the retainer (18) extending outside the holding window (18c) is formed in the. 2. The torque converter according to claim 1, wherein the outer race (15) is connected to a stator hub (4h).
The torque converter characterized in that the annular recess (30) is formed in the end wall (27) by cutting while press-fitting into the inner peripheral surface of the outer race (15) and finish cutting the inner peripheral surface of the outer race (15).