JP5167218B2 - Torque converter - Google Patents

Description

  The present invention relates to a torque converter, and more particularly to a torque converter for transmitting torque from an engine to a transmission side via a fluid.

  The torque converter is a device that has a torus (impeller, turbine, stator) composed of three types of impellers, and transmits power by a fluid inside the torus. The impeller forms a fluid chamber filled with hydraulic oil together with the front cover. The impeller mainly includes an annular impeller shell, a plurality of impeller blades fixed inside the impeller shell, and an annular impeller core fixed inside the impeller blade. The turbine is disposed in the fluid chamber so as to face the impeller in the axial direction. The turbine mainly includes an annular turbine shell, a plurality of turbine blades fixed to an impeller side surface of the turbine shell, and an annular turbine core fixed to the inside of the turbine blade. The inner peripheral part of the turbine shell is fixed to the flange of the turbine hub by a plurality of rivets. The turbine hub is connected to the input shaft in a relatively non-rotatable manner. The stator is a mechanism for rectifying the flow of hydraulic oil returning from the turbine to the impeller, and is disposed between the inner peripheral portion of the impeller and the inner peripheral portion of the turbine. The stator mainly includes an annular shell, a plurality of stator blades provided on the outer peripheral surface of the shell, and an annular stator core fixed to the tips of the plurality of stator blades. The stator shell is supported by a fixed shaft via a one-way clutch (see Patent Document 1).

  In order to improve the efficiency of the torque converter as shown in Patent Document 1, a four-element type torque converter as shown in Patent Document 2, for example, has been proposed. This four-element type torque converter is obtained by dividing one stator in Patent Document 1 into two parts to improve efficiency.

JP2007-21118A JP 2003-287104 A

  Since the four-element type torque converter as described above is provided with two stators, the cost is higher than that of a general three-element type torque converter. Therefore, in the four-element type torque converter, it is desired to suppress the manufacturing cost.

  An object of the present invention is to suppress the manufacturing cost in a four-element type torque converter.

A torque converter according to claim 1 is for transmitting torque from an engine to a transmission side via a fluid, and includes a front cover to which torque from the engine is input, an impeller, a turbine, One stator and a second stator are provided. The impeller constitutes a fluid chamber together with the front cover, and has a plurality of impeller blades and an impeller core that supports the plurality of impeller blades. The turbine includes a plurality of turbine blades facing the impeller blades and a turbine core that supports the plurality of turbine blades, and can output torque to the transmission. The first stator has a plurality of first stator blades that are arranged on the turbine side between the inner peripheral portion of the impeller and the inner peripheral portion of the turbine and rectify the flow of fluid flowing from the turbine to the impeller. Yes. The second stator is disposed on the impeller side between the inner periphery of the impeller and the inner periphery of the turbine, and has a plurality of second stator blades for rectifying the flow of fluid flowing from the turbine to the impeller. Yes. The second stator has an annular core ring that supports the second stator blade, and the core ring is formed to extend to the outer peripheral portion of the first stator blade. I also use it.

  Here, since the core of two stators is shared by one core ring, manufacturing cost can be reduced.

The torque converter according to a second aspect is the torque converter according to the first aspect , wherein the impeller core and the turbine core have the same shape. Here, the parts can be shared, and the manufacturing cost can be reduced.

The torque converter according to claim 3 is the torque converter according to claim 2 , wherein the working fluid inlet side radius of the impeller and the working fluid outlet side radius of the turbine are different.

The torque converter according to a fourth aspect is the torque converter according to any one of the first to third aspects, wherein the second stator blade has a projecting portion projecting to the outer peripheral side at the end of the outer peripheral portion on the working fluid inlet side. The convex portion is engaged with the inner peripheral portion of the core ring, and the core ring is positioned in the axial direction.

The torque converter according to a fifth aspect is the torque converter according to any one of the first to fourth aspects, wherein a tip end portion of the extension portion of the core ring has a tapered shape extending to the outer peripheral side.

  Here, since the tip of the extension part of the core ring, that is, the turbine outlet side portion extends to the outer peripheral side, it is possible to suppress the hydraulic oil flowing out from the turbine to the first stator from leaking to the outside of the first stator. it can.

  In the present invention as described above, the manufacturing cost can be reduced in the four-element type torque converter having the split stator.

1 is a schematic longitudinal sectional view of a torque converter according to an embodiment of the present invention. The partially expanded view of FIG. The figure which compares and shows the characteristic of this embodiment and the conventional torque converter.

[Configuration of torque converter]
FIG. 1 is a schematic longitudinal sectional view of a torque converter 1 in which an embodiment of the present invention is employed. The torque converter 1 includes a front cover 2 and a torque converter main body 3, and is a device for transmitting torque from an engine crankshaft to an input shaft of a transmission. An engine (not shown) is arranged on the left side of FIG. 1, and a transmission (not shown) is arranged on the right side of FIG. OO shown in FIG. 1 is a rotating shaft of the torque converter 1.

  The front cover 2 is a disk-shaped member, and a center boss 5 is fixed to the inner peripheral end by welding. The center boss 5 is a cylindrical member extending in the axial direction, and is inserted into a center hole of a crankshaft (not shown). An outer peripheral cylindrical portion 2 a extending toward the axial transmission side is formed on the outer peripheral portion of the front cover 2.

  The torque converter body 3 includes a torus-shaped fluid working chamber 14 including an impeller 10, a turbine 11, a first stator 12, and a second stator 13, and a lockup device 15.

  The impeller 10 is fixed to an impeller shell 17 constituting an outer shell, an inner core 18, a plurality of impeller blades 19 fixed between the impeller shell 17 and the core 18, and an inner peripheral portion of the impeller shell 17. And the impeller hub 20. And the outer periphery of the impeller shell 17 is being fixed to the outer peripheral side cylindrical part 2a of the front cover 2 by welding.

  The turbine 11 is disposed on the engine side so as to face the impeller 10. The turbine 11 is fixed to a turbine shell 21 constituting an outer shell, an inner core 22, a plurality of turbine blades 23 fixed between the turbine shell 21 and the core 22, and an inner peripheral portion of the turbine shell 21. The turbine hub 24 is made up of. The turbine shell 21 and the turbine hub 24 are fixed by a plurality of rivets 25. A spline hole that engages with the input shaft of the transmission is formed in the inner peripheral surface of the turbine hub 24. Thereby, the turbine hub 24 rotates integrally with the input shaft.

  The working fluid inlet side radius R1 of the impeller 10 is larger than the working fluid outlet side radius R2 of the turbine 11. Here, as described above, the radius of each element is a radial dimension at the intersection of the design path Dp (see FIG. 1) and the edge of the blade of each element. In addition, the “design path” here is a line in which, when an annular line segment is set along the fluid flow, the flow path areas on one side and the other side divided by the line segment are equal. Minutes.

  The first stator 12 is a mechanism for rectifying the flow of hydraulic oil that is disposed on the engine side between the inner peripheral portion of the impeller 10 and the inner peripheral portion of the turbine 11 and returns from the turbine 11 to the impeller 10. The first stator 12 includes an annular first stator shell 26 and a plurality of first stator blades 27 provided on the outer peripheral surface of the first stator shell 26. The first stator 12 is integrally formed by casting with resin, aluminum alloy or the like. The first stator shell 26 is supported by a cylindrical fixing shaft 30 via a first one-way clutch 29.

  The second stator 13 is disposed on the transmission side between the inner peripheral portion of the impeller 10 and the inner peripheral portion of the turbine 11, and rectifies the flow of hydraulic oil returning from the turbine 11 to the impeller 10 together with the first stator 12. Mechanism. The second stator 13 includes an annular second stator shell 32, a plurality of second stator blades 33 provided on the outer peripheral surface of the second stator shell 32, and an annular shape fixed to the tips of the plurality of second stator blades 33. And the coring 34. The second stator shell 32 and the second stator blade 33 of the second stator 13 are integrally formed by casting with resin, aluminum alloy or the like. The annular core ring 34 is formed by forming a steel plate in a band shape and welding and fixing the end portion. The second stator shell 32 is supported by a cylindrical fixing shaft 30 via a second one-way clutch 35.

  Further, between the turbine hub 24 and the outer ring of the first one-way clutch 29, between the outer ring of the first one-way clutch 29 and the outer ring of the second one-way clutch 35, and between the outer ring of the second one-way clutch 35 and the impeller hub 20. Are provided with thrust bearings 37, 38, 39, respectively.

  The lock-up device 15 has the same configuration as a conventionally known device used in a torque converter, and a detailed description thereof is omitted here.

[About the core of each member]
As described above, the working fluid inlet side radius R1 of the impeller 10 and the working fluid outlet side radius R2 of the turbine 11 are different, but the impeller core 18 and the turbine core 22 have the same shape. For this reason, the parts can be shared.

  The first stator 12 is not provided with a core, and the core ring 34 of the second stator 13 also serves as the core of the first stator 12.

  More specifically, as shown in an enlarged view in FIG. 2, the core ring 34 of the second stator 13 includes a support portion 34 a that supports the outer peripheral end portion of the second stator blade 33, and the support portion 34 toward the turbine 11 side. And an extending portion 34b.

  The support portion 34a is inclined to the inner peripheral side from the impeller 10 side to the turbine 11 side, and the end portion on the turbine side is inclined to the outer peripheral side. Further, the second stator blade 33 is formed with a convex portion 33a projecting to the outer peripheral side at the end of the outer peripheral portion on the first stator 12 side (working fluid inlet side). And this convex part 33a is latched to the part which inclines to the outer peripheral side of the support part 34a. With such a configuration, the core ring 34 is positioned in the axial direction.

  The extension part 34 b extends substantially in parallel along the rotation axis and covers the outer peripheral part of the first stator blade 27. And the front-end | tip part (end part by the side of the turbine 11) of the extension part 34b is formed in the taper shape extended to an outer peripheral side. With the tapered portion 34c, the hydraulic oil flowing out from the turbine 11 can be smoothly guided into the first stator 12, and the hydraulic oil can be prevented from leaking outside the first stator 12. it can.

[Arrangement of first stator and second stator]
The first stator 12 is disposed on the inner peripheral side with respect to the second stator 13. The stators 12 and 13 will be described in more detail. The first stator 12 has an inner peripheral edge 27a (shell-side edge) and an outer peripheral edge 27b (core-side edge) of the first stator blade 27, both of which have a rotational axis O. Parallel to -O. In the second stator 13, the inner peripheral edge (shell side edge) of the second stator blade 33 is formed substantially along the shape of the impeller shell 17. That is, the inner peripheral edge of the second stator blade 33 is located at the innermost end near the first stator 12, and the innermost peripheral part is substantially the same position as the inner peripheral edge of the first stator 12. . The inner peripheral edge of the second stator blade 33 has an arc shape so as to be positioned on the outer peripheral side as the distance from the first stator 12 increases.

  Further, in the first stator blade 27 of the first stator 12, the edge portion 27 c on the inlet side of the fluid on the turbine 11 side is formed substantially perpendicular to the rotation axis OO, and the edge portion on the outlet side 27d is inclined so that the inner peripheral side is located on the transmission side as compared with the outer peripheral side. With such a shape, the axial length of the first stator 12 is secured, and a good rectifying effect of the working fluid can be obtained in the first stator 12.

[Torque converter operation]
The basic operation of the torque converter in this embodiment is the same as the operation of a general conventional torque converter. That is, when the lockup is released, torque transmission between the front cover 2 and the turbine 11 is performed by fluid drive between the impeller 10 and the turbine 11. Specifically, when the impeller 10 is rotated together with the front cover 2, the hydraulic oil flows from the impeller 10 to the turbine 11 by centrifugal force. The hydraulic oil flowing from the impeller 10 to the turbine 11 rotates the turbine 11 and then passes through the first stator 12 and the second stator 13. When passing through the stators 12 and 13, the hydraulic oil that has collided with the stator blades 27 and 33 is redirected by the blades and returned to the impeller 13.

  When the lockup device is on, torque from the front cover 2 is directly transmitted to the turbine hub 24 via the lockup device 15.

[Feature]
In such an embodiment, the impeller 10 and the turbine 11 are not formed symmetrically. However, since the impeller core 28 and the turbine core 22 have the same shape, the parts can be shared, and the manufacturing cost can be increased. Can be suppressed.

  Further, an extension 34b is formed in the core ring 34 of the second stator 13, and the extension 34b has a function of the core ring of the first stator 12. That is, the core ring 34 of the second stator 13 is also used as the core ring of the first stator 12. For this reason, the number of parts can be suppressed, and the manufacturing cost can be further reduced.

  The second stator blade 33 is provided with a convex portion 33a, and the convex portion 33a is engaged with the core ring 34 to position the core ring 34 in the axial direction. For this reason, it is possible to position the core ring 34 in the axial direction with a simple configuration.

  A tapered portion 34c extending to the outer peripheral side is formed at the end of the extended portion 34b of the core ring 34 on the turbine 11 side. For this reason, the hydraulic oil flowing out from the turbine 11 can be smoothly guided into the first stator 12, and leakage of the hydraulic oil to the outside of the first stator 12 can be suppressed.

  The first stator 12 and the second stator 13 are not arranged symmetrically as in the prior art, but the first stator 12 is arranged on the inner peripheral side and the second stator 13 is arranged on the outer peripheral side. The exit radius of 13 is relatively large. For this reason, a stator torque increases and a torque ratio can be improved. FIG. 3 shows a torque ratio T1 (broken line) of a conventional four-element type torque converter and a torque ratio T2 (solid line) of the torque converter of the present embodiment. As is apparent from this characteristic diagram, the torque ratio of the apparatus of this embodiment is increased compared to the conventional apparatus, particularly in the low speed range and the medium speed range.

  As the exit radius of the second stator 13 increases, the entrance radius R1 of the impeller 10 increases, leading to a reduction in the capacity of the torque converter. However, here, by arranging the first stator 12 on the inner peripheral side, the entrance radius of the first stator 12 is reduced, and a reduction in capacity can be suppressed. FIG. 3 shows the capacity C1 (broken line) of the conventional four-element type torque converter and the capacity C2 (solid line) of the torque converter of the present embodiment. As is apparent from this characteristic diagram, the capacitance is not particularly changed.

  From the above, it is apparent that the torque ratio of the present embodiment can be improved while the capacity is substantially the same as that of the conventional torque converter.

[Other Embodiments]
The present invention is not limited to the above-described embodiments, and various changes or modifications can be made without departing from the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Torque converter 2 Front cover 3 Torque converter main body 10 Impeller 11 Turbine 12 1st stator 13 2nd stator 18 Impeller core 19 Impeller blade 22 Turbine core 23 Turbine blade 27 1st stator blade 33 2nd stator blade 34 Core ring 34a Support part 34b Extension

Claims (5)

A torque converter for transmitting torque from an engine to a transmission side via a fluid,
A front cover that receives torque from the engine;
An impeller that constitutes a fluid chamber together with the front cover and has a plurality of impeller blades and an impeller core that supports the plurality of impeller blades;
A turbine having a plurality of turbine blades opposed to the impeller blades and a turbine core supporting the plurality of turbine blades, and capable of outputting torque to the transmission;
A first stator blade disposed between the inner peripheral portion of the impeller and the inner peripheral portion of the turbine and disposed on the turbine side and configured to rectify a flow of fluid flowing from the turbine to the impeller. A stator,
A second stator blade disposed between the inner peripheral portion of the impeller and the inner peripheral portion of the turbine and disposed on the impeller side to rectify a flow of fluid flowing from the turbine to the impeller. A stator,
With
The second stator has an annular core ring that supports the second stator blade, and the core ring is formed to extend to an outer peripheral portion of the first stator blade. Also used for coring,
Torque converter. The torque converter according to claim 1 , wherein the impeller core and the turbine core have the same shape. The torque converter according to claim 2 , wherein a working fluid inlet side radius of the impeller and a working fluid outlet side radius of the turbine are different. The second stator blade has a convex portion protruding to the outer peripheral side at an end portion on the working fluid inlet side in the outer peripheral portion, and the convex portion is engaged with an inner peripheral portion of the core ring, and the core The torque converter according to any one of claims 1 to 3 , wherein the ring is positioned in the axial direction. The torque converter according to any one of claims 1 to 4 , wherein a distal end portion of the extension portion of the coring has a tapered shape extending to an outer peripheral side.

Images