JP2008309258A - Torque converter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a torque converter capable of wholly satisfying weight reduction, durability and size reduction, by making a pump shell with a pump hub of a pump impeller by a press. <P>SOLUTION: The pump impeller 2 has an annular retainer plate 18 braided to the pump shell 2s and pressing and holding an end part of a pump blade 2b to the pump shell 2s side. The retainer plate 18 is constituted of a pressing part 18a pressing and holding the pump blade 2b by integrally forming the pump hub 2h by bending an inner peripheral end part of the pump shell 2s outward in the axial direction and a reinforcing wall part 18b extending inward in the radial direction from this pressing part 18a and joined to a bending part 26 curved between the pump shell 2s and the pump hub 2h. A thrust needle bearing 30 is interposed between this reinforcing wall part 18h and a stator hub 4h. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pump impeller connected to a drive shaft, a turbine impeller connected to the pump impeller and connected to a turbine shaft, and a stator disposed between the pump impeller and the inner peripheral portion of the turbine impeller. An impeller, and a stator hub of the stator impeller is coupled to a hollow stator shaft that is rotatably supported on the outer periphery of the drive shaft, and the pump hub of the pump impeller is rotatably supported on the stator shaft. In addition, the present invention relates to an improvement in a torque converter in which a bearing is interposed between the axially facing surfaces of the pump hub and the stator hub.

In such a conventional torque converter, for example, as disclosed in Patent Document 1, the pump impeller is integrally formed by casting, so that the weight is heavy and it is difficult to reduce the weight of the entire torque converter. In addition, as shown in Patent Document 2, it is also known that the pump shell of the pump impeller is made of press. However, the pump hub is made of cast material and welded to the pump shell. What can be ensured, and dissatisfaction remained in terms of weight reduction, and the size of the area around the pump hub became large, which hindered the overall compactness of the torque converter.
JP 2006-46483 A JP 2003-214524 A

  The present invention has been made in view of such circumstances, and enables the press production of a pump shell of a pump impeller with a pump hub to satisfy all of weight reduction, durability and compactness. The purpose is to provide.

  To achieve the above object, the present invention provides a pump impeller connected to a drive shaft, a turbine impeller connected to the pump impeller and connected to a turbine shaft, and the inside of the pump impeller and the turbine impeller. A stator impeller disposed between peripheral portions, and a stator hub of the stator impeller is coupled to a hollow stator shaft that is rotatably supported on the outer periphery of the drive shaft, and the pump blade is coupled to the stator shaft In a torque converter in which a pump hub of a car is rotatably supported and a bearing is interposed between the axially facing surfaces of the pump hub and the stator hub, the pump impeller is made of a press and has a cross-sectional saddle shape and an annular shape. A pump shell, a plurality of pump blades brazed to the inner surface of the pump shell and arranged in the circumferential direction thereof, and the pump shell And an annular retainer plate that presses and holds the end of the pump blade on the inner peripheral side of the pump shell toward the pump shell, and the inner peripheral end of the pump blade is axially outward. The pump hub is integrally formed by bending the retainer plate, and the retainer plate extends inward in the radial direction from the press portion that presses and holds the pump blade, and is curved between the pump shell and the pump hub. A first feature is that a thrust needle bearing as the bearing is interposed between the reinforcing wall portion and the stator hub. The drive shaft corresponds to the crankshaft 1 in an embodiment of the present invention described later.

  In addition to the first feature, the present invention has a second feature in that the thrust needle bearing is arranged so that the center of the needle roller is within the axial projection plane of the pump hub.

  According to the present invention, in addition to the second feature, the inner surface of the reinforcing wall is cut to form a flat seat surface perpendicular to the rotational axis of the pump impeller, and the thrust surface is provided with the thrust surface. The third feature is that the needle bearing is supported.

  According to the first aspect of the present invention, the pump hub is formed integrally with the press pump shell by bending the inner peripheral end thereof outward in the axial direction, and the inner peripheral end of the pump shell and the stator hub. By interposing a thrust needle bearing between them, it is possible to reduce the diameter of the pump hub and shorten the axial dimension of the torque converter, thereby contributing to the compactness of the torque converter, and smooth relative between the pump shell and the stator hub. Rotation can be guaranteed.

  In addition, a reinforcing wall portion of the retainer plate that presses and holds the pump blade on the inner surface of the pump shell is joined to a curved bent portion between the pump shell and the pump hub, and a thrust needle bearing is interposed between the reinforcing wall portion and the stator hub. As a result, the thrust load bearing part of the pump shell can be reinforced using the retainer plate effectively, which can contribute to the improvement of the durability of the torque converter.

  According to the second feature of the present invention, the thrust load from the thrust needle bearing can be directly received by the pump hub, and the deformation and inclination of the pump hub can be reliably prevented.

  According to the third aspect of the present invention, the seat surface can be expanded radially inward, and the thrust needle bearing of the arrangement can be supported stably, and the thrust needle bearing can be reduced in diameter. Therefore, the torque converter can be made compact.

  Embodiments of the present invention will be described below on the basis of preferred embodiments of the present invention shown in the accompanying drawings.

  1 is a longitudinal sectional view of a torque converter according to the present invention, FIG. 2 is an enlarged view of part 2 of FIG. 1, FIG. 3 is a sectional view taken along line 3-3 of FIG. 2, and FIG. .

  First, in FIG. 1, a torque converter T mounted on a small vehicle such as a motorcycle or a buggy is interposed between a crankshaft 1 of an engine as a drive shaft and a multistage auxiliary transmission (not shown). This torque converter T includes a pump impeller 2, a turbine impeller 3 having an outer peripheral portion opposed to the outer peripheral portion thereof, and a stator impeller 4 disposed between the inner peripheral portions thereof. , 3 and 4, a circulation circuit 5 for power transmission by hydraulic oil is defined. A side cover 6 that covers the outer surface of the turbine impeller 3 is integrally connected to the outer peripheral end of the pump impeller 2 via a welded portion W1. A cover hub 6h is connected to the center portion of the side cover 6 via a welded portion W2.

  In the turbine impeller 3, a turbine hub 3 h is rotatably supported on the crankshaft 1 via a ball bearing 8, and the cover hub 6 h of the side cover 6 adjacent to the outside of the ball bearing 8 is attached to the crankshaft 1. Splined. The cover hub 6h and the inner race 8a of the ball bearing 8 are sandwiched between an annular shoulder 1a on the outer periphery of the crankshaft 1 and a nut 9 screwed onto the crankshaft 1. Thus, the pump impeller 2 is fixed to the crankshaft 1.

  The inner end of the turbine hub 3h is coupled to the inner end of the turbine shaft 10 which is fitted to the outer peripheral surface of the crankshaft 1 in a relatively rotatable manner by a welded portion W3, and is fitted to the outer peripheral surface of the turbine shaft 10 in a relatively rotatable manner. The stator hub 4h of the stator impeller 4 is spline-fitted to the inner end of the cylindrical stator shaft 11 to be joined. A free wheel 12 is connected to an outer end portion of the stator shaft 11 protruding outward from the pump impeller 2. This free wheel 12 is a known one, and an outer cylinder 13 welded to the outer end of the stator shaft 11 and an inner cylinder supported on the stator shaft 11 in the outer cylinder 13 via a bearing bush 24 so as to be relatively rotatable. 14 and a plurality of sprags 15 interposed between these inner and outer cylinders 14 and 13, and the inner cylinder 14 has a flange 16 welded to one end thereof to a fixed structure 23 such as a crankcase. By being locked to the fixed pin 17 provided, it is impossible to rotate.

  Now, the configuration of the pump impeller 2 will be described with reference to FIGS. 1 and 2.

  The pump impeller 2 includes a pump shell 2s having a bowl-shaped and annular cross section, a pump core ring 2r having a bowl-shaped cross section disposed inside the pump shell 2s, and a space between the pump shell 2s and the pump core ring 2r. A plurality of pump blades 2b arranged in an annular shape so as to be integrally connected, and an annular retainer plate 18 that presses and holds the pump shell 2s on the inner peripheral side of the pump blade 2s against the pump shell 2s. The The pump shell 2s, the pump core ring 2r, the pump blade 2b, and the retainer plate 18 are all made of a press made of a steel plate.

  As shown in FIGS. 1 and 2, a plurality of first and second positioning recesses 20a and 21a arranged in the circumferential direction are formed on the inner peripheral end and the outer peripheral end of the inner surface of the pump shell 2s, respectively. A plurality of positioning holes 22a arranged in the circumferential direction are formed in the core ring 2r. On the other hand, each pump blade 2b is formed with first, second and third positioning claws 20b, 21b and 22b which engage with the first and second positioning recesses 20a and 21a and the positioning hole 22a, respectively. The retainer plate 18 is initially temporarily fixed by spot welds W4 at several points on the circumference in order to press and hold the radially inner end of the group of pump blades 2b against the pump shell 2s. Each engagement state between the positioning recesses 20a, 21a and the first and second positioning claws 20b, 21b is maintained, and the engagement state between the positioning hole 22a and the third positioning claws 22b is maintained. In this state, the pump shell 2s, the pump blade 2b, the pump core ring 2r, and the retainer plate 18 are brazed. In FIG. 2, the code | symbol 28 shows the solidified brazing material.

  The pump shell 2s is integrally formed with a pump hub 2h whose inner peripheral end is bent outward in the axial direction by press molding. The pump hub 2h is formed on the outer peripheral surface of the stator shaft 11 via a bearing bush 7. It is supported so that it can rotate freely. An annular inward flange 25 that holds the outer end of the bearing bush 24 is integrally formed at the outer end of the pump hub 2h. Due to the press molding of the pump hub 2h, a bent portion 26 is formed between the pump shell 2s and the pump hub 2h by bending in a range of 90 °.

  In FIG. 2, the retainer plate 18 presses and holds the pump blade 2b, and extends radially inward from the presser portion 18a. The retainer plate 18 has a curved bent portion 26 between the pump shell 2s and the pump hub 2h. The reinforcing wall portion 18b is overlapped and brazed to the pump shell 2s. As shown in FIG. 4B, a flat seat surface 27 orthogonal to the rotational axis of the pump impeller 2 is formed on the inner side surface of the reinforcing wall portion 18b by cutting. Thus, the seating surface 27 extends radially inward by a distance s from the flat inner side surface of the reinforcing wall portion 18b before cutting shown in FIG.

  A thrust needle bearing 30 is interposed between the seat surface 27 and one end surface of the stator hub 4h that opens to the seat surface 27. The thrust needle bearing 30 is provided on one end surface of the stator hub 4h while supporting a plurality of needle rollers 31 arranged in an annular shape, an annular roller retainer 32 for holding the needle rollers 31, and one side surface of the group of needle rollers 31. The first seat plate 33 is in contact with a second seat plate 34 that is in contact with the seat surface 27 while supporting the other side of the needle roller 31 group. A cylindrical shaft 33a that is rotatably supported on the outer peripheral surface is integrally provided, and the roller retainer 32 and the second seat plate 34 are rotatably supported by the outer peripheral surface of the cylindrical shaft 33a. The thrust needle bearing 30 can be easily mounted on the stator shaft 11 by fitting the cylindrical shaft 33 a to the outer peripheral surface of the stator shaft 11. The thrust needle bearing 30 is arranged such that the needle roller 31 is centered within the axial projection plane A of the pump hub 2h.

  The other end surface of the stator hub 4h contacts the inner end surface of the turbine hub 3h together with the inner end surface of the stator shaft 11. Thus, the stator hub 4h is restrained from moving in the axial direction between the thrust needle bearing 30 and the turbine hub 3h.

  On the other hand, as shown in FIG. 1, the turbine impeller 3 is configured by brazing a press-made turbine shell 3s, a turbine core ring 3r, a plurality of turbine blades 3b, and an annular retainer plate 19, respectively. A turbine hub 3h is coupled to the inner peripheral end of the turbine shell 3s by a weld W5.

  In FIG. 1, a supply oil passage 40 and a discharge oil passage 41 are coaxially formed in the center portion of the crankshaft 1 with a partition wall 1 b integrated with the crankshaft 1 interposed therebetween. The supply oil passage 40 is supplied with working oil from an oil pump 39 driven by the crankshaft 1, and a first inclined oil hole 43 of the crankshaft 1 is provided at the downstream end of the supply oil passage 40. A first annular oil passage 44 between the crankshaft 1 and the turbine shaft 10, a first oil hole 45 in the turbine shaft 10, a second annular oil passage 46 between the turbine shaft 10 and the stator shaft 11, and the stator shaft 11 The second oil hole 47 and a plurality of first cutouts 48 on one end face of the stator hub 4h contacting the first seat plate 33 are sequentially communicated with the circulation circuit 5 on the pump impeller 2 side. In the circulation circuit 5, a plurality of second notches 49 on the other end surface of the turbine hub 3h that abuts on the other end surface of the stator hub 4h, a third annular oil passage 50 between the stator shaft 11 and the turbine shaft 10, and the turbine shaft 10, the third oil hole 51, the fourth annular oil passage 52 between the turbine shaft 10 and the crankshaft 1, and the second inclined oil hole 53 of the crankshaft 1 are communicated with the discharge oil passage 41 in order. The downstream side of the oil passage 41 communicates with each part of the engine.

  Next, the operation of this embodiment will be described.

  During operation of the engine, the working oil supplied from the oil pump 39 to the supply oil passage 40 is a first inclined oil hole 43, a first annular oil passage 44, a first oil hole 45, a second annular oil passage 46, a second oil oil. The oil is introduced into the circulation circuit 5 on the pump impeller 2 side through the oil hole 47 and the first notch 48 in order, thereby filling the circuit 5. The working oil in the circulation circuit 5 passes through the second notch 49, the third annular oil passage 50, the third oil hole 51, the fourth annular oil passage 52, and the second inclined oil hole 53 in this order to the discharge oil passage 41. Discharged. In this way, the circulation circuit 5 can always be filled with new hydraulic oil, and each part of the torque converter T can be lubricated and cooled.

  Thus, when the pump impeller 2 is rotated by the crankshaft 1 of the engine, the working oil filling the circulation circuit 5 is pumped by the centrifugal force as indicated by the arrow in FIG. The rotational torque of the pump impeller 2 is transmitted to the turbine impeller 3 while circulating from the impeller 3 to the stator impeller 4 to the pump impeller 2, and is transmitted from the turbine shaft 10 to the vehicle driving wheel through a transmission (not shown). And you can drive it.

  At the time of torque amplification between the pump impeller 2 and the turbine impeller 3 in the torque converter T, the accompanying reaction force is borne by the stator impeller 4, and the stator impeller 4 is rotated by the locking action of the freewheel 12. Be blocked.

  When the torque amplification is completed, the stator impeller 4 rotates in the same direction together with the turbine impeller 3 while rotating the free wheel 12 by reversing the torque direction received by the stator impeller 4.

  By the way, the pump impeller 2 includes a press-made pump shell 2s having a bowl-shaped and annular cross section, a plurality of pump blades 2b that are brazed to the inner surface of the pump shell 2s and arranged in the circumferential direction, An annular retainer plate 18 that is brazed to the shell 2s and presses and holds the end of the pump blade 2b on the inner peripheral side of the pump shell 2s toward the pump shell 2s is provided. The pump shell 2s has an inner peripheral end thereof. The pump hub 2h is integrally formed by bending the portion outward in the axial direction, the retainer plate 18 is pressed against and held by the pump blade 2b, and the holding portion 18a extends radially inward from the holding portion 18a. The reinforcing wall 18b is brazed to the pump shell 2s so as to overlap the curved bent portion 26 between the shell 2s and the pump hub 2h. Since the thrust needle bearing 30 is interposed between the wall 18b and the stator hub 4h, that is, the pump hub 2h is integrally formed by bending the inner peripheral end of the pump shell 2s made of press outward in the axial direction. In addition, the thrust needle bearing 30 is interposed between the inner peripheral end of the pump shell 2s and the stator hub 4h, thereby reducing the diameter of the pump hub 2h and shortening the axial dimension of the torque converter T. And a smooth relative rotation between the pump shell 2s and the stator hub 4h can be ensured.

  Further, the reinforcing wall portion 18b of the retainer plate 18 which is brazed to the inner side surface of the pump shell 2s to press and hold the pump blade 2b is overlapped with the curved bent portion 26 between the pump shell 2s and the pump hub 2h, and this reinforcing wall portion. By interposing the thrust needle bearing 30 between 18b and the stator hub 4h, the thrust load bearing portion of the pump shell 2s can be reinforced by using the retainer plate 18 effectively, and the durability of the torque converter T can be improved. Can also contribute.

  Moreover, since the thrust needle bearing 30 is arranged so that the center C of the needle roller 31 is within the axial projection plane A of the pump hub 2h, the thrust load from the thrust needle bearing 30 can be directly received by the pump hub 2h. Thus, deformation and inclination of the pump hub 2h can be reliably prevented.

  Further, since a flat seat surface 27 perpendicular to the rotation axis of the pump impeller 2 is formed by cutting on the inner side surface of the reinforcing wall portion 18b of the retainer plate 18, the seat surface 27 is formed in the radial direction. As a result, the thrust needle bearing 30 having the above arrangement can be supported stably, and the diameter of the thrust needle bearing 30 can be reduced, and the torque converter T can be made compact.

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

The longitudinal cross-sectional view of the torque converter of this invention. FIG. 2 is an enlarged view of part 2 of FIG. 1. FIG. 3 is a sectional view taken along line 3-3 in FIG. 2. Manufacturing process explanatory drawing of a pump impeller.

Explanation of symbols

A ... Axial projection surface of pump hub C ... Needle roller center T ... Torque converter 1 ... Drive shaft (crankshaft)
2 ... Pump impeller 2b ... Pump blade 2h ... Pump hub 2s ... Pump shell 3 ... Turbine impeller 4 ... Stator impeller 4h ··· Stator hub 10 ··· Turbine shaft 11 ··· Stator shaft 18 ··· Retainer plate 18a ··· Holding portion 18b ··· Reinforcement wall portion 26 ··· Bending portion 27 ··· Seat 30 · · · Thrust needle bearing 31 · · · Needle roller

Claims (3)

A pump impeller (2) connected to the drive shaft (1), a turbine impeller (3) connected to the pump impeller (2) and connected to the turbine shaft (10), and the pump impeller ( 2) and a stator impeller (4) disposed between the inner peripheral portions of the turbine impeller (3), and a stator hub (4h) of the stator impeller (4) on the outer periphery of the drive shaft (1). A hollow stator shaft (11) supported so as to be relatively rotatable is coupled, and the pump hub (2h) of the pump impeller (2) is rotatably supported on the stator shaft (11), and the pump hub (2h) And a torque converter having a bearing interposed between axially opposed surfaces of the stator hub (4h),
The pump impeller (2) is made of a press and has a bowl-shaped and annular pump shell (2s), and a plurality of pumps that are brazed to the inner surface of the pump shell (2s) and arranged in the circumferential direction thereof The end of the pump shell (2s) on the inner peripheral side of the pump blade (2b) is pressed and held against the pump shell (2s) by brazing to the blade (2b) and the pump shell (2s) An annular retainer plate (18), and the pump hub (2h) is formed integrally with the pump shell (2s) by bending the inner peripheral end thereof outward in the axial direction, and the retainer plate (18) The presser part (18a) that presses and holds the pump blade (2b), extends radially inward from the presser part (18a), and includes the pump shell (2s) and the pump hub (2 ) And a reinforcing wall portion (18b) joined to the curved bent portion (26) between the reinforcing wall portion (18b) and the stator hub (4h). A torque converter characterized by comprising (30). The torque converter according to claim 1,
A torque converter characterized in that the thrust needle bearing (30) is arranged so that the center (C) of the needle roller (31) is within the axial projection surface (A) of the pump hub (2h). The torque converter according to claim 2,
The inner wall surface of the reinforcing wall portion (18b) is cut to form a flat seat surface (27) orthogonal to the rotation axis of the pump impeller (2), and the thrust needle is formed on the seat surface (27). A torque converter characterized in that a bearing (30) is supported.

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