JP3881152B2 - Impeller and fluid torque transmission device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a fluid torque transmission device, and more particularly to a fluid torque transmission device for transmitting torque by circulating fluid between a plurality of impellers.
[0002]
[Prior art]
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 (not shown) via a one-way clutch.
[0003]
As described above, each impeller includes a plurality of blades, a shell provided on the outer side of each blade (a side away from the center in the torus cross section), and an inner side of each blade (a side close to the center in the torus cross section). ). A space further divided by the blade between the shell and the core is a flow path of each impeller.
[0004]
[Problems to be solved by the invention]
In the stator, in the low speed ratio region of the torque converter, the hydraulic oil abuts against the pressure surface of the blade and changes its flow direction, and then flows to the impeller to boost the impeller. As a result, a torque increasing action is performed. In the high speed ratio range, the hydraulic oil comes into contact with the suction surface of the blade, and the stator rotates by the function of the one-way clutch to prevent a decrease in transmission efficiency.
[0005]
In the low speed ratio region, as shown in FIG. 8, the angle at which the hydraulic oil 205 collides with the pressure surface 201 of the blade 200 is large. Accordingly, various vortices such as a turbulent flow 202 and a backflow 203 may occur between the blades 200. As described above, the flow of hydraulic oil is disturbed, so that the performance such as capacity and efficiency of the torque converter can be reduced.
[0006]
An object of the present invention is to ensure a smooth flow of fluid in an impeller used in a fluid torque transmission device.
[0007]
[Means for Solving the Problems]
The impeller according to claim 1 is used in a fluid torque transmission device for transmitting torque by circulating fluid between a plurality of impellers. The impeller includes an impeller main body, a plurality of blades provided on the impeller main body to form a flow path, and a vortex for providing a micro vortex for buffering on a surface provided in the flow path where the fluid of the blade collides. And a generator. The vortex generator is formed in the impeller body.
[0008]
In this impeller, the micro vortex generated by the vortex generator is provided on the surface of the blade where the fluid collides, so that the fluid collides with the blade not through the micro vortex but directly. Therefore, the collision of the fluid is alleviated and various vortices resulting from the collision are less likely to occur.
[0009]
According to a second aspect of the present invention, in the first aspect, the vortex generator is provided near the entrance of the flow path.
[0010]
According to a third aspect of the present invention, in the first or second aspect, the vortex generator provides a micro vortex in the vicinity of the impeller body on the surface where the fluid of the blade collides.
[0011]
Since various vortices are likely to occur near the blade impeller body, the effect is high in that they are not generated.
[0012]
In an impeller according to a fourth aspect, in any one of the first to third aspects, the vortex generating portion is a protrusion or a recess formed in the impeller body .
[0013]
According to a fifth aspect of the present invention, at least one impeller according to any one of the first to fourth aspects is used.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
First embodiment
Configuration FIG. 1 is a schematic longitudinal sectional view of a torque converter 1 in which one embodiment of the present invention is adopted. The torque converter 1 is a device for transmitting torque from an engine crankshaft 2 to an input shaft (not shown) 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. The OO line shown in FIG. 1 is the rotating shaft of the torque converter 1.
[0015]
The torque converter 1 mainly includes a flexible plate 4 and a torque converter body 5. The flexible plate 4 is a member made of a thin disc-like plate material, which transmits torque and absorbs bending vibration input to the torque converter 1 from the crankshaft 2 side.
[0016]
The torque converter body 5 includes a torus 6 including three types of impellers (impeller 18, turbine 19, stator 20) and a lockup device 7.
[0017]
The front cover 14 is a disk-shaped member and is disposed in the vicinity of the flexible plate 4. A center boss 15 is fixed to the inner periphery of the front cover 14 by welding. The center boss 15 is a cylindrical member extending in the axial direction, and is inserted into the center hole of the crankshaft 2.
[0018]
The inner peripheral portion of the flexible plate 4 is fixed to the crankshaft 2 by a plurality of bolts 10. A plurality of nuts 11 are fixed at equal intervals in the circumferential direction on the outer peripheral side of the front cover 14 and the engine side. A bolt 12 screwed into the nut 11 fixes the outer peripheral portion of the flexible plate 4 to the front cover 14. An annular ring gear member 13 is fixed to the outer peripheral portion of the flexible plate 4.
[0019]
An outer peripheral cylindrical portion 16 extending toward the axial transmission side is formed on the outer peripheral portion of the front cover 14. The outer peripheral edge of the impeller shell 22 of the impeller 18 is fixed to the tip of the outer peripheral cylindrical portion 16 by welding. As a result, the front cover 14 and the impeller 18 form a fluid chamber filled with hydraulic oil (fluid). The impeller 18 is mainly fixed to an impeller shell 22, a plurality of impeller blades 23 fixed to the inside of the impeller shell 22, an impeller core 17 fixed to the inside of the blade 23, and an inner peripheral portion of the impeller shell 22. The impeller hub 24 is made up of.
[0020]
The turbine 19 is disposed to face the impeller 18 in the axial direction in the fluid chamber. The turbine 19 mainly includes a turbine shell 25, a plurality of turbine blades 26 fixed to the impeller side surface of the turbine shell 25, and an annular turbine core 37 fixed to the inside of the blade 26. . An inner peripheral portion of the turbine shell 25 is fixed to a flange of the turbine hub 27 by a plurality of rivets 28. The turbine hub 27 is connected to an input shaft (not shown) so as not to be relatively rotatable.
[0021]
The stator 20 is a mechanism for rectifying the flow of hydraulic oil returning from the turbine 19 to the impeller 18. The stator 20 is an integral member manufactured by casting with resin, aluminum alloy or the like. The stator 20 is disposed between the inner periphery of the impeller 18 and the inner periphery of the turbine 19. The stator 20 mainly includes an annular stator shell 29, a plurality of stator blades 30 provided on the outer peripheral surface of the shell 29, and an annular stator core 31 fixed to the tips of the plurality of stator blades 30. Yes. The core 31 secures an annular space together with the core 17 and the core 37. The shell 29 is supported by a fixed shaft (not shown) via a one-way clutch 32.
[0022]
The one-way clutch 32 is supported by an outer race 33 fixed to the shell 29 and an inner race 34 fixed to a fixed shaft. A thrust bearing 39 is disposed between the shell 29 and the impeller hub 24. An annular locking member 36 is arranged on the axial engine side of the outer race 33 of the one-way clutch 32. The locking member 36 prevents the member of the one-way clutch 32 from dropping off in the axial direction. A thrust bearing 40 is disposed between the locking member 36 and the turbine hub 27.
[0023]
Next, the structure of the blade 30 and the like in the stator 20 will be described. The shell 29 has an outer peripheral surface 29a having a certain length in the axial direction. The outer peripheral surface 29a is formed straight in the axial direction in the cross section. The blade 30 is fixed from the impeller 18 side of the outer peripheral surface 29a and extends outward in the radial direction. As shown in FIG. 3, each of the blades 30 has a blade-shaped cross section. FIG. 3 shows a cross-sectional shape near the base (near the shell) of each blade 30. The end of the blade 30 on the turbine 19 side is a rounded head, and the end of the impeller 18 is an elongated tail. Furthermore, the pressure surface 30a of the blade 30 has a curved concave shape, and the suction surface 30b has a curved convex shape.
[0024]
A plurality of protrusions 29 b are formed on the outer peripheral surface 29 a of the shell 29 on the part closer to the axial engine side than the blade 30. The protrusions 29b have a minute protrusion shape that slightly protrudes radially outward from the outer peripheral surface 29a, and a plurality of protrusions 29b are formed in the circumferential direction. As shown in FIG. 3, the protrusions 29 b are disposed correspondingly between the blades 30.
[0025]
Next, the lockup device 7 will be described. The lockup device 7 is mainly composed of a piston member 44 and a damper mechanism 45. The piston member 44 is a disk-shaped member that is disposed close to the axial engine side of the front cover 14. The piston member 44 is a recess that is narrowed so that the radially intermediate portion protrudes toward the axial transmission side. The front cover 14 is formed with an annular recess corresponding to the recess of the piston member 44. An inner peripheral cylindrical portion 48 extending toward the axial transmission side is formed on the inner peripheral portion of the piston member 44. The inner peripheral cylindrical portion 48 is supported on the outer peripheral surface of the turbine hub 27 so as to be capable of relative rotation and axial movement. The axial transmission side end portion of the inner peripheral cylindrical portion 48 is in contact with the flange portion of the turbine hub 27, so that the movement toward the axial transmission side is limited to a predetermined position. A seal ring 49 is disposed on the outer peripheral surface of the turbine hub 27, and the seal ring 49 seals an axial space in the inner peripheral portion of the piston member 44.
[0026]
The outer peripheral portion of the piston member 44 functions as a clutch coupling portion. An annular friction facing 46 is fixed on the engine side of the outer periphery of the piston member 44. The friction facing 46 is opposed to an annular and flat friction surface formed on the inner surface of the outer peripheral portion of the front cover 14. A plurality of protrusions 47 extending toward the axial transmission side are formed on the outer periphery of the piston member 44.
[0027]
The damper mechanism 45 includes a drive member 52, a driven member 53, and a plurality of torsion springs 54 (elastic connecting portions). The drive member 52 includes a pair of plate members 56 and 57 arranged side by side in the axial direction. The outer peripheral portions of the pair of plate members 56 and 57 are in contact with each other and are fixed to each other by a plurality of rivets 55. A plurality of protrusions extending in the radial direction so as to engage with the protrusions 47 are formed on the outer peripheral edges of the pair of plate members 56 and 57. By this engagement, the piston member 44 and the drive member 52 can move relative to each other in the axial direction, but rotate together in the rotational direction. The pair of plate members 56 and 57 are arranged such that their inner peripheral portions are spaced apart from each other in the axial direction. A plurality of first and second support portions 56a and 57a arranged in the circumferential direction are formed on the inner peripheral portions of the plate members 56 and 57, respectively. The first and second support portions 56a and 57a have a structure for storing and supporting a torsion spring 54, which will be described later. Specifically, the first and second support portions 56a and 57a are cut and raised portions on both sides in the radial direction cut and raised in the axial direction. The driven member 53 is a disk-shaped member. The driven member 53 is disposed between the axial directions of the first and second plate members 56 and 57, and the inner peripheral portion is fixed to the flange of the turbine hub 27 by a plurality of rivets 28. A window hole 58 is formed in the driven member 53 in correspondence with the first and second support portions 56a and 57a. The window hole 58 is a hole extending long in the circumferential direction. The plurality of torsion springs 54 are accommodated in the window holes 58 and the first and second support portions 56a and 57a. The torsion spring 54 is a coil spring extending in the circumferential direction, and both ends in the circumferential direction are supported by the window holes 58 and the circumferential ends of the first and second support portions 56a and 57a. Further, the axial movement of the torsion spring 54 is limited by the cut and raised portions of the first and second support portions 56a and 57a.
[0028]
Operation When torque is transmitted from the engine (not shown) to the crankshaft 2, torque is transmitted to the front cover 14 and the impeller 18 through the flexible plate 4. The hydraulic oil driven by the impeller blades 23 of the impeller 18 rotates the turbine 19. The torque of the turbine 19 is output to an input shaft (not shown) via the turbine hub 27. The hydraulic fluid flowing from the turbine 19 to the impeller 18 flows to the impeller 18 side through a passage determined by the shell 29 and the core 31 of the stator 20.
[0029]
Here, the hydraulic oil flowing in the vicinity of the outer peripheral surface 29 a of the shell 29 of the stator 20 collides with the protrusion 29 b and generates a micro vortex 60. As shown in FIG. 3, the micro vortex 60 flows to the pressure surface 30a of the blade 30 and further flows along the pressure surface 30a. For this reason, the hydraulic oil 61 does not directly collide with the pressure surface 30 a but collides with the pressure surface 30 a through the minute vortex 60. Thus, since the flow velocity of the collision of the hydraulic oil 61 is suppressed, unlike the prior art, the turbulence of the flow and the backflow hardly occur. In other words, the hydraulic oil 61 flows through the stator 20 smoothly. As a result, the torque converter 1 is unlikely to decrease in efficiency and capacity.
[0030]
When the hydraulic fluid in the space between the front cover 14 and the piston member 44 is drained from the inner peripheral side, the piston member 44 moves to the front cover 14 side due to the hydraulic pressure difference, and the friction facing 46 is brought to the friction surface of the front cover 14. Pressed. As a result, torque is transmitted from the front cover 14 to the turbine hub 27 via the lockup device 7.
[0031]
In the above-described embodiment, the protrusion 29 b is formed on the shell 29, and mainly supplies a micro vortex near the carrier side (base side) of the blade 30. As a result, the flow of the hydraulic oil is smoothed most efficiently. This is because, as a result of the inventor paying attention to the problems of various vortices and considering them through experiments and the like, it has been found that various vortices are likely to occur particularly near the shell side of the stator.
Second Embodiment A vortex generating portion for generating a micro vortex is not limited to a protrusion, and may be a recess such as a slit, groove, or notch. In the torque converter shown in FIG. 4, a plurality of grooves 29 c are formed on the outer peripheral surface of the shell 29. The groove 29c is formed extending in the axial direction from the axial engine side edge of the outer peripheral surface 29a. The grooves 29 c are arranged in the circumferential direction corresponding to the blades 30. The groove 29c also generates a micro vortex as in the above embodiment. As a result, the same effect as in the above embodiment can be obtained.
[0032]
In the above-described two embodiments, minute vortices are generated in the stator (especially in the vicinity of the shell 29) in order to suppress the generation of various vortices in the stator. However, in order to realize the same function, the outlet of the turbine is used. You may provide the vortex generating part which consists of a protrusion and a recessed part in the vicinity (especially turbine shell side).
Third Embodiment In the present embodiment, as shown in FIG. 5, a plurality of protrusions 31 a are formed on the core 31 of the stator 20. The protrusion 31 a is provided at the end of the core 31 on the axial direction engine side. The effect obtained by this is the same as in the above embodiment. In addition, you may form a recessed part in the core 31 instead of protrusion.
Fourth Embodiment In the present embodiment, as shown in FIG. 6, a plurality of protrusions 25 a are formed inside the turbine shell 25 near the entrance of the turbine 19. The protrusions 25a are arranged in the circumferential direction correspondingly between the plates 26. The effect obtained by this is the same as in the above embodiment. In addition, you may form a recessed part in the shell 25 instead of protrusion.
[0033]
A plurality of protrusions 37 a are formed at the inlet side end of the turbine core 37. The protrusions 37a are arranged in the circumferential direction correspondingly between the plates 26. The effect obtained by this is the same as in the above embodiment. In addition, you may form a recessed part in the core 37 instead of protrusion.
[0034]
In this embodiment, the vortex generator is formed in both the shell 25 and the core 37, but an excellent effect can be obtained with either one.
Fifth Embodiment In the present embodiment, as shown in FIG. 7, a plurality of protrusions 22 a are formed inside the impeller shell 22 in the vicinity of the entrance of the impeller 18. The protrusions 22a are arranged in the circumferential direction correspondingly between the plates 23. The effect obtained by this is the same as in the above embodiment. In addition, you may form a recessed part in the shell 22 instead of protrusion.
[0035]
A plurality of protrusions 17 a are formed at the entrance end of the impeller core 17. The protrusions 17a are arranged in the circumferential direction correspondingly between the plates 23. The effect obtained by this is the same as in the above embodiment. In addition, you may form a recessed part in the core 17 instead of protrusion.
[0036]
In this embodiment, the vortex generating part is formed in both the shell 25 and the core 17, but an excellent effect can be obtained in either one.
Other Embodiments All of the above embodiments may be combined, or may be combined as necessary to realize one torque converter.
[0037]
The vortex generating portion is not limited to a single protrusion or recess, but includes a concavo-convex portion formed by a combination of the protrusion and the recess or a structure that generates a micro vortex by a rough surface having a fine concavo-convex surface.
[0038]
The present invention is not limited to a torque converter, but can be applied to other fluid torque transmission devices such as fluid couplings.
[Brief description of the drawings]
FIG. 1 is a schematic longitudinal sectional view of a torque converter as a first embodiment of the present invention.
FIG. 2 is a partially enlarged view of FIG.
FIG. 3 is a view for explaining the positional relationship between the stator blades and the vortex generator and the flow of hydraulic oil.
FIG. 4 is a schematic longitudinal sectional view of a torque converter as a second embodiment of the present invention.
FIG. 5 is a schematic longitudinal sectional view of a torque converter as a third embodiment of the present invention.
FIG. 6 is a schematic vertical sectional view of a torque converter as a fourth embodiment of the present invention.
FIG. 7 is a schematic longitudinal sectional view of a torque converter as a fifth embodiment of the present invention.
FIG. 8 is a view for explaining the positional relationship between the stator blades and the vortex generator and the flow of hydraulic oil.
[Explanation of symbols]
1 Torque Converter 2 Crankshaft 20 Stator (Impeller)
29 Shell (impeller body)
29a Outer peripheral surface 29b Protrusion (vortex generator)
30 Stator blade 31 Core

Claims (5)

An impeller used in a fluid torque transmission device for transmitting torque by circulating fluid between a plurality of impellers,
The impeller body,
A plurality of blades provided on the impeller body to form a flow path;
A vortex generator for providing a buffering micro vortex on the surface of the blade that the fluid of the blade collides with,
The vortex generator is an impeller formed in the impeller body . The impeller according to claim 1 , wherein the vortex generating part is provided near an entrance of the flow path.   The impeller according to claim 1 or 2, wherein the vortex generator is configured to provide the minute vortex in the vicinity of the impeller main body on a surface where the fluid of the blade collides. The impeller according to any one of claims 1 to 3, wherein the vortex generator is a protrusion or a recess formed in the impeller body.   A hydrodynamic torque transmission device in which at least one of the impellers according to claim 1 is provided.

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