JP2006329345A - Manufacturing method of torque converter, and torque converter manufactured by the method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem of an uneven contact of a thrust bearing when an outer race is press-fitted for engaging with the inside of a stator for the outer peripheral side of a side part to protrude outside in an axial direction. <P>SOLUTION: In the manufacturing method of a torque converter, an outer race 18 is press-fitted for engagement with the inside of a stator 15 for torque amplifying action. A one-way clutch is provided inside the outer race 18. A side part 15a provided with a abutment surface 15b to which a thrust bearing abuts is integrally molded with the stator 15. Such a slope as inner peripheral side of the abutment surface 15b protrudes outside the outer peripheral side in the axial direction is molded, and then the outer race 18 is press-fitted for engagement with the inside of the stator 15, so that the outer peripheral side of the abutment surface 15b protrudes in the axial direction, allowing the abutment surface 15b almost perpendicular to an axis. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a torque converter manufacturing method and a torque converter manufactured by the manufacturing method, and relates to a technique for press-fitting an outer race inside a stator.

  A motor vehicle is provided with a torque converter as a torque transmission device between an engine crankshaft and a transmission.

  As a conventional torque converter, for example, one disclosed in Patent Document 1 is known. In the torque converter, a stator is disposed between the pump impeller and the turbine runner in order to amplify the torque transmitted from the pump impeller to the turbine runner. An outer race is press-fitted and fitted inside the stator, and an inner race whose rotation is restricted via a one-way clutch is provided inside the outer race.

An outer race made of carbon steel is fitted inside the aluminum stator, and a spline is formed on the outer peripheral surface of the outer race. Therefore, the spline cuts aluminum during press fitting, and the inner peripheral surface of the stator. The press-fitting is performed while forming a spline.
JP 11-153207 A

  However, when the outer race is press-fitted into the cylindrical portion of the stator, the cylindrical portion is pushed and expanded to the outer peripheral side, and therefore, the side surface that covers one side surface of the outer race and the one-way clutch disposed inside the stator due to the influence. The outer peripheral side of the portion is bent so as to protrude outward, and the outer surface of the side portion becomes an inclined surface.

  The outer surface of the side surface portion of the stator is a contact surface on which the roller of the thrust bearing rolls in order to receive a thrust load. If the corresponding contact surface is an inclined surface, one end of the roller strongly contacts the contact surface. It will be in a single-contact state and the life of the thrust bearing will be shortened.

  In order to avoid such a state, the abutting surface may be machined into a flat surface after press-fitting the outer race, but a new machining process and mechanical equipment are required, resulting in an increase in production cost.

  Accordingly, an object of the present invention is to solve the above-described problems and provide a torque converter manufacturing method and a torque converter manufactured by the manufacturing method that do not require machining of a contact surface after press-fitting.

  According to a first aspect of the present invention, there is provided a pump impeller connected to a crankshaft of an engine, a turbine runner to which a rotational force of the pump impeller is transmitted via a fluid and connected to an input shaft of a transmission, and the pump A stator disposed between the impeller and the turbine runner for amplifying the torque transmitted from the pump impeller to the turbine runner, an outer race fitted inside the stator, and a one-way clutch inside the outer race In the method of manufacturing a torque converter, in which an inner race is provided via an inner race, and a side surface portion that covers one side surface of the outer race and has a contact surface with which a thrust bearing abuts is formed integrally with the stator. After the peripheral side is molded into an inclined surface protruding in the axial direction from the outer peripheral side, the step is By press-fitted into the outer race to the inside of the motor, wherein the abutment surface is set to be substantially perpendicular to the axis.

  According to the present invention, since the inner peripheral side of the contact surface is formed in advance into an inclined surface protruding outward in the axial direction from the outer peripheral side, the inner peripheral surface of the stator can be obtained by press-fitting the outer race inside the stator. When the outer peripheral side of the contact surface protrudes outward in the axial direction due to the expansion of the contact surface, both the inner peripheral side and the outer peripheral side protrude outward in the axial direction. It is flat and does not require machining.

  According to a second aspect of the present invention, in the torque converter manufacturing method according to the first aspect, a spline is formed on the outer peripheral surface of the outer race, and the outer race is press-fitted into the stator made of a material softer than the outer race. It is characterized by being fitted.

  According to the present invention, since the spline is formed on the outer peripheral surface of the outer race to be press-fitted, the inner side of the stator that is softer than the outer race is cut and splined by the spline, and the pressure input can be reduced. Therefore, the amount of deformation of the stator due to press-fitting and the variation in the amount of deformation are reduced, and the setting of the inclination angle of the contact surface before press-fitting becomes easy. Therefore, implementation of the invention is facilitated.

  The invention according to claim 3 is the torque converter manufacturing method according to claim 2, wherein the spline is formed by rolling or sintering.

  According to the present invention, since the spline is formed on the outer race by rolling or sintering without time-consuming machining, the manufacturing cost of the torque converter is reduced.

  According to a fourth aspect of the present invention, in the torque converter manufacturing method according to the third aspect, after the spline is formed, a circumferential groove is formed by machining on the side surface side of the outer peripheral surface of the outer race. It is characterized by.

  According to the present invention, the end edge portion of the spline formed by rolling or sintering is sharpened and sharpened by machining, so the end edge portion of the spline is press-fitted while cutting the inner peripheral surface of the stator. As a result, the press-fitting is performed smoothly. In addition, since the sharpness of the end edge portion of the spline is stabilized, variations in the deformation of the stator are suppressed, and the implementation of the invention is stably performed.

  The invention of a torque converter according to claim 5 is manufactured by the method for manufacturing a torque converter according to any one of claims 1 to 4.

  According to the torque converter of the present invention, the contact surface formed on the side surface portion of the stator is a flat surface that is substantially perpendicular to the shaft, so that the roller of the thrust bearing comes into contact without any contact.

  According to the torque converter manufacturing method of the present invention, when the outer race is press-fitted and fitted inside the stator, the inner peripheral surface of the stator is expanded, and the outer peripheral side of the contact surface of the side surface portion is axially affected by the influence. Since it protrudes outward, the inner peripheral side of the contact surface is formed in advance into an inclined surface protruding outward in the axial direction from the outer peripheral side so as to cancel out this deformation. A state in which neither the inner peripheral side nor the outer peripheral side of the surface protrudes outward in the axial direction, that is, the contact surface becomes a plane substantially perpendicular to the shaft, and the contact surface does not need to be machined.

  According to the torque converter of the present invention, the abutment surface formed on the side surface portion of the stator is a plane that is substantially perpendicular to the shaft, and the thrust bearing roller abuts against one side, and the life of the thrust bearing is increased. There is no shrinkage.

Embodiments of a torque converter according to the present invention and embodiments of the torque converter manufactured by the manufacturing method will be described below.
(A) Embodiment 1
First, the outline of the configuration and operation of the torque converter will be described, and then the parts constituting the invention will be described in detail.

  The configuration of the torque converter is shown in FIG. An engine crankshaft (not shown) is provided on the right side of the torque converter 1. A converter cover 2 on the right side of the torque converter 1 is coupled to the crankshaft via a plurality of bolts 5 welded to the converter cover 2 and a drive plate (not shown), and a pump impeller 3 is coupled to the converter cover 2. Thereby, the converter housing 4 which is an outer frame is comprised. The pump impeller 3 is composed of an impeller shell 3a, a plurality of blades 8 and a core 6. A rotational force is transmitted to an oil pump of a transmission (not shown) on the left side of the torque converter 1 at the axial center position of the impeller shell 3a. A sleeve 7 is connected by welding.

  On the other hand, a turbine hub 9 is spline-fitted to an input shaft (not shown) of the transmission, and a turbine runner 10 and a driven plate 11 are coupled to the turbine hub 9 via rivets 12. The turbine runner 10 includes a turbine shell 10a, a plurality of blades 13, and a core 14. A stator 15 is provided between the pump impeller 3 and the turbine runner 10 in the axial direction, and the stator 15 is set to be rotatable only in one direction.

  When the rotational speed of the converter housing 4 exceeds a predetermined value, the lock-up piston 19 is connected to the outer peripheral surface of the cylindrical portion of the turbine hub 9 via the seal ring 23 so that the pump impeller 3 and the turbine runner 10 can be directly connected. The friction material 28 is bonded to the lock-up piston 19 at a position in contact with the inner surface of the converter cover 2. The lockup piston 19 and the turbine hub 9 that are directly connected to the converter cover 2 are connected to each other via a vibration damper 20 that is disposed on the outer side in the radial direction. The vibration damper 20 is constituted by a holding plate 21 that is coupled to the lock-up piston 19 and holds the spring 24, and the driven plate 11 that compresses the spring 24 with the holding plate 21.

  Thrust needle bearings 31 as thrust bearings are provided on both sides of the stator 15. That is, a thrust needle bearing 31 that receives axial thrust is provided between a bearing support 27 and a turbine hub 9 and between the sleeve 7 and the stator 15, which will be described later.

  The operation of the torque converter 1 having the above configuration will be described. When torque is input from the crankshaft (not shown) to the converter housing 4, the torque is transmitted to the turbine runner 10 via the fluid in the converter housing 4, and is transmitted from the turbine hub 9 to the input shaft (not shown) of the adjacent transmission on the left. Is done. In an operating state in which the difference in rotational speed between the pump impeller 3 and the turbine runner 10 is large, the torque amplification action by the stator 15 works and the turbine runner 10 is rotated with a large torque. When the difference in rotational speed between the pump impeller 3 and the turbine runner 10 is reduced, the torque amplification action is lost, and power is transmitted from the pump impeller 3 to the turbine runner 10 simply as a fluid coupling.

  When the converter housing 4 rotates at a predetermined speed or higher, the lock-up piston 19 controlled by the pressure of the hydraulic fluid in the control chamber 29 moves to the right, and the friction material 28 presses against the inner surface of the converter cover 2. Then, the lockup piston 19 is directly connected to the converter cover 2. For this reason, the rotational torque of the converter cover 2 is transmitted directly to the turbine hub 9 via the lockup piston 19 and the vibration damper 20 without passing through the fluid in the converter housing 4.

  Next, the configuration in the vicinity of the stator 15 will be described. An outer race 18 is press-fitted inside the stator 15, and an inner race 16 is provided inside the outer race 18 via a one-way clutch 17, and the inner race 16 is in a state in which rotation is restricted. That is, the inner race 16 is splined to a fixed stator shaft (not shown). In the present embodiment, the outer race 18 is made of carbon steel, and the stator 15 is made of aluminum made of a softer material than the outer race 18. A side surface portion 15 a that covers the left side surface of the outer race 18, the one-way clutch 17, and the inner race 16 is integrally formed with the stator 15. On the other hand, a bearing support 27 covering the right side surface of the outer race 18, the one-way clutch 17 and the inner race 16 is provided in a state of being fitted inside the outer race 18. The side surface portion 15a and the bearing support 27 are for supporting the stator 15 via the thrust needle bearing 31, and a contact surface 15b with which the thrust needle bearing 31 abuts is formed on the side surface portion 15a.

  As shown in FIG. 1B, the stator 15 includes a cylindrical portion 15c, an annular portion 15d, a blade 15e formed between the cylindrical portion 15c and the annular portion 15d, and an axial direction of the cylindrical portion 15c. It is comprised by the side part 15a formed toward the transmission side toward the center part. The side surface portion 15a of the stator 15 is an inclined surface in which the inner peripheral side B of the contact surface 15b protrudes outward in the axial direction from the outer peripheral side A (the entire contact surface 15b has the shape of an outer peripheral surface of a truncated cone. The outer race 18 is then press-fitted and fitted inside the stator 15.

  More specifically, when the outer race 18 is press-fitted and fitted as shown in FIG. 2B from the state where the inner peripheral side B protrudes outward in the axial direction as shown in FIG. Since a force is applied from the outer race 18 so as to spread the cylindrical portion 15c, the side surface portion 15a bends as shown by an arrow (b), and the outer peripheral side A of the contact surface 15b slightly protrudes outward in the axial direction. The outer peripheral side A and the inner peripheral side B have the same height in the axial direction, and the contact surface 15b is substantially perpendicular to the axis. The amount of protrusion on the inner peripheral side B that is projected in advance is determined by measuring the actual amount of protrusion on the outer peripheral side A due to the press-fitting of the outer race 18, and by projecting the inner peripheral side B, the protrusion amount of the contact surface 15b is determined. The inclination angle is θ. That is, the thickness of the side surface portion 15a is slightly larger on the inner peripheral side B than on the outer peripheral side A. The contact surface 15b may be formed by machining, or cast by high precision casting.

  Since the inner peripheral side B of the contact surface 15b is preliminarily formed into an inclined surface protruding outward in the axial direction from the outer peripheral side A, the inner periphery of the stator 18 can be obtained by press fitting the outer race 18 inside the stator 15. When the outer surface A of the contact surface 15b protrudes outward in the axial direction when the surface is widened, both the inner peripheral side B and the outer peripheral side A protrude outward in the axial direction. The plane is substantially perpendicular to the plane, and machining is not necessary.

After forming a spline on the outer peripheral surface of the carbon steel outer race 18 by machining, when the outer race 18 is press-fitted inside the stator 15 made of aluminum, the inside of the stator 15 made of soft aluminum is cut by the spline and spline processed. Therefore, the pressure input is small, and the deformation amount of the stator 15 due to the press-fitting and the variation in the deformation amount can be reduced. Therefore, it becomes easy to set the inclination angle θ of the contact surface 15b.
(B) Embodiment 2
Next, a second embodiment will be described. Since the second embodiment is obtained by changing a part of the first embodiment, the description of the same part is omitted, and only a different part is described.

  In this embodiment, splines are formed on the outer peripheral surface of the outer race 18 by rolling or sintering. After rolling or sintering, the outer race 18 can be press-fitted inside the stator 15 without machining.

In this case, since the spline can be formed without machining, the machining time can be omitted and the manufacturing cost of the torque converter is reduced.
(C) Embodiment 3
Next, a third embodiment will be described. Since the third embodiment is obtained by changing a part of the second embodiment, the description of the same part is omitted, and only a different part is described.

  FIG. 3 shows the outer race 18. After the spline 18a is formed on the outer peripheral surface of the outer race 18 by rolling or sintering, a circumferential groove 18b is formed by machining on the left side of FIG. 3A, which is the side surface side of the outer peripheral surface of the outer race 18. Yes. The circumferential groove 18b is provided in order to collect a cut piece generated by cutting the stator 15 without taking it out. Although the circumferential groove 18b can be formed by rolling or sintering, in this embodiment, it is formed by machining. Therefore, as shown in FIG. 4, the end edge portion 18c of the spline 18a formed by rolling or sintering is sharpened and sharpened by machining, and the end edge portion 18c of the spline 18a is fixed to the stator during press-fitting. The press-fitting is performed more smoothly by press-fitting while cutting the inner peripheral surface of 15. Further, since the sharpness of the end edge portion 18c of the spline 18a is stabilized, variations in the deformation of the stator 15 are suppressed, and the invention is stably performed.

  In the torque converter manufactured by the torque converter manufacturing method according to any one of the first to third embodiments, the contact surface formed on the side surface portion of the stator is a plane substantially perpendicular to the shaft. For this reason, the roller of the thrust bearing that supports the stator 15 in the axial direction comes into contact with each other without coming into contact with each other. Therefore, the life of the thrust bearing is not shortened.

  In the embodiment, the spline is formed on the outer peripheral surface of the outer race and the outer race is press-fitted to the inside of the stator. However, the outer race may be press-fitted without forming the spline. Further, in this embodiment, a combination of carbon steel and aluminum is shown as a combination of the outer race and the stator made of a material softer than the outer race. However, the present invention is not limited to this combination, and various combinations can be considered. It is done. Furthermore, although the one-way clutch shown in the embodiment is a sprag type, it is also effective to apply a roller-type one-way clutch. When a roller type one-way clutch is applied, the outer race is generally made by sintering and can be manufactured at low cost.

(A) is a front view, (b) is an AA arrow view of (a) (Embodiment 1). (A) is a sectional view of the stator before the outer race is press-fitted into the stator, and (b) is a sectional view of the stator after the press-fitting (Embodiment 1). FIG. 4A is a cross-sectional view of an outer race of a torque converter, and FIG. The principal part enlarged view of outer race (Embodiment 3). The block diagram which shows a torque converter (embodiment 1).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Torque converter 3 ... Pump impeller 10 ... Turbine runner 15 ... Stator 15a ... Side part 15b ... Contact surface 16 ... Inner race 17 ... One-way clutch 18 ... Outer race 18a ... Spline 18b ... Circumferential groove 31 ... Thrust needle bearing

Claims (5)

A pump impeller connected to the crankshaft of the engine; a turbine runner in which the rotational force of the pump impeller is transmitted via fluid and connected to the input shaft of the transmission; and between the pump impeller and the turbine runner And a stator for amplifying torque transmitted from the pump impeller to the turbine runner,
An outer race is fitted on the inner side of the stator, an inner race is provided on the inner side of the outer race via a one-way clutch, and a side surface portion having a contact surface that covers one side surface of the outer race and contacts a thrust bearing is provided. In the manufacturing method of the torque converter integrally formed with the stator,
After the contact surface is formed into an inclined surface whose inner peripheral side protrudes in the axial direction from the outer peripheral side, the outer race is press-fitted inside the stator so that the contact surface is substantially perpendicular to the shaft. A method for manufacturing a torque converter, characterized in that: 2. The method of manufacturing a torque converter according to claim 1, wherein a spline is formed on an outer peripheral surface of the outer race, and the outer race is press-fitted into the stator made of a material softer than the outer race. Torque converter manufacturing method. 3. The method of manufacturing a torque converter according to claim 2, wherein the spline is formed by rolling or sintering. 4. The torque converter manufacturing method according to claim 3, wherein a circumferential groove is formed by machining on the side surface side of the outer peripheral surface of the outer race after the spline is formed. Method. A torque converter manufactured by the method for manufacturing a torque converter according to claim 1.

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