Patent ID: 12203537

DETAILED DESCRIPTION OF EMBODIMENTS

Hereinafter, a mode for carrying out the present disclosure will be described with reference to the drawings.

As shown inFIG.1, a damper device1is mounted inside a torque converter2. The damper device1is located in a torque transmission path between an internal combustion engine3and a transmission4. The internal combustion engine3may be either a gasoline engine or a diesel engine. The transmission4may be a stepped transmission in which the gear ratio changes stepwise, or may be a continuously variable transmission in which the gear ratio changes continuously. The damper device1reduces vibration of torque generated by the internal combustion engine3and transfers the resultant torque to the transmission4.

The torque converter2includes a housing5. Oil for torque transmission is sealed in the housing5. The housing5includes a front cover6and a pump shell7. The front cover6is connected to an output shaft3aof the internal combustion engine3. The pump shell7is integral with the front cover6. The torque converter2is liquid-tight by the front cover6and the pump shell7.

A plurality of pump blades8is attached to the pump shell7. A pump impeller9is formed by attaching the pump blades8to the pump shell7. A turbine runner10is placed so as to face the pump impeller9. The turbine runner10rotates as it receives an oil flow generated by the pump impeller9. The turbine runner10has a shape symmetrical to the shape of the pump impeller9. The turbine runner10includes a turbine shell (not shown) and a large number of turbine blades11attached to the inner surface of the turbine shell. The turbine runner10is connected to an input shaft4aof the transmission4via a turbine hub12.

A stator13is located between the pump impeller9and the turbine runner10. The stator13is attached to a fixed shaft (not shown) in the torque converter2via a one-way clutch14. The stator13changes the flow direction of oil flowing out of the turbine runner10when the speed ratio between the pump impeller9and the turbine runner10is low. On the other hand, when this speed ratio is high, the stator13does not change the flow direction of the oil as the stator13is pushed by the oil flowing out of the turbine runner10and rotates. Therefore, the one-way clutch14is engaged to stop rotation of the stator13when this speed ratio is low, and allows the stator13to rotate when this speed ratio is high.

A lockup clutch15facing the inner surface of the front cover6is located inside the front cover6. The lockup clutch15includes a plurality of clutch discs16and a plurality of clutch plates18. That is, the lockup clutch15is a multi-disc clutch. The clutch discs16are spline-fitted on a clutch hub that is integral with the front cover6. The clutch plates18are arranged alternately with the clutch discs16. The clutch plate18are each spline-fitted to an inner peripheral surface of a clutch drum17located so as to cover the outer periphery of the clutch hub.

The clutch discs16and the clutch plates18are alternately arranged between a lockup piston (not shown) and a snap ring (not shown) attached to the clutch drum17. When the lockup piston advances and presses the clutch discs16and the clutch plates18against the snap ring, the clutch discs16and the clutch plates18are in frictional contact with each other, and torque is transferred therebetween. That is, the lockup clutch15is engaged so that torque is transferred.

Although not shown in the figures, a return spring is placed on the inner peripheral side of the lockup clutch15in the radial direction of the torque converter2so as to be located next to at least a part of the lockup clutch15. The return spring presses the lockup piston in the direction of disengaging the lockup clutch15, that is, in the direction of separating the clutch discs16and the clutch plates18. As described above, the torque converter2includes the lockup clutch15, the lockup piston, the clutch discs16, and the turbine hub12.

The damper device1is located between the turbine hub12and at least one of the following components: the lockup clutch15, the lockup piston, and the clutch discs16. The damper device1is located adjacent to the lockup clutch15in the direction of the rotation center axis (hereinafter, simply referred to as the rotation axis) of the torque converter2. A disk-shaped or annular piston plate21is connected to the clutch drum17of the lockup clutch15. An annular retainer plate22is connected and fixed to the piston plate21by rivets23. The retainer plate22is an example of the input-side rotating member, and is rotatable about the rotation axis. Bolts may be used instead of the rivets23. The piston plate21is located closer to the lockup clutch15than the retainer plate22in the direction of the rotation axis.

The piston plate21and the retainer plate22are located at a predetermined interval in the direction of the rotation axis. Since the piston plate21and the retainer plate22are connected to each other, the piston plate21and the retainer plate22rotate together while maintaining this interval. The piston plate21and the retainer plate22are thus located on the upstream side in the torque transfer direction. An annular intermediate plate27that is a separate member from the retainer plate22is mounted on the outer peripheral portion of the retainer plate22. The intermediate plate27is an example of the intermediate rotating member, and is rotatable independently of and relative to the retainer plate22about the rotation axis on an outer side of the retainer plate22.

An output plate26is located on the downstream side in the torque transfer direction of the piston plate21and the retainer plate22in the direction of the rotation axis. The output plate26is an example of an output-side rotating member, and is rotatable on an inner side of the intermediate plate27and relative to the intermediate plate27. The output plate26is connected to the intermediate plate27via torsion springs28as elastic bodies so that the output plate26can rotate at a predetermined angle relative to the retainer plate22and the intermediate plate27.

More specifically, as shown inFIG.2, the intermediate plate27surrounds the outer peripheries of the retainer plate22and the output plate26. The torsion springs28are arranged on the inner side of the intermediate plate27in the circumferential direction. The intermediate plate27elastically connects the retainer plate22and the output plate26in the rotational direction by the torsion springs28. The torsion springs28include a first torsion spring S1, a second torsion spring S2, a third torsion spring S3, a fourth torsion spring S4, etc. The first torsion spring S1is an example of the first elastic body, and the second torsion spring S2is an example of the second elastic body. The intermediate plate27operates the torsion springs28in series. The intermediate plate27can rotate relative to the retainer plate22and the output plate26while sliding independently of the rotational motion of the retainer plate22and the output plate26.

The intermediate plate27has, in its inner periphery, four inner peripheral protruding portions including inner peripheral protruding portions27P,27Q at intervals of approximately 90 degrees about the rotation axis O. Spring contact portions27R are both side surfaces in the circumferential direction of each inner peripheral protruding portion, and each spring contact portion27R supports one of the ends of a corresponding torsion spring28. The intermediate plate27has an inner peripheral flange portion27S in its inner peripheral edge portion excluding the inner peripheral protruding portions.

The retainer plate22has, in its outer periphery, four outer peripheral protruding portions22A,22B,22C, and22D as hook portions at intervals of approximately 90 degrees about the rotation axis O. For example, the outer peripheral protruding portion22A is located at an interval of 45 degrees from the inner peripheral protruding portion27P. The remaining outer peripheral protruding portions22B,22C, and22D are also located at an interval of 45 degrees from the inner peripheral protruding portions. Both side surfaces in the circumferential direction of each outer peripheral protruding portion22A,22C are outer peripheral spring contact portions22E, and each outer peripheral spring contact portion22E supports the other end of a corresponding torsion spring28. Both side surfaces in the circumferential direction of each outer peripheral protruding portion22B,22D are outer peripheral spring contact portions22F, and each outer peripheral spring contact portion22F separates the other end of a corresponding torsion spring28from the outer peripheral protruding portion22B,22D.

Each of the tip ends of the outer peripheral protruding portions22A,22B,22C, and22D of the retainer plate22has a two-step hook, namely a tip upper hook and a tip lower hook (see alsoFIGS.4A and4B). The outer peripheral protruding portions22A,22B,22C, and22D are located on opposite sides of the piston plate21(seeFIG.1), and slidably hold the inner peripheral flange portion27S of the intermediate plate27by the tip upper and lower hooks. The inner peripheral surface of the intermediate plate27other than the inner peripheral flange portion27S supports the outer peripheral side surfaces of the torsion springs28.

The output plate26has, in its outer periphery, four outer peripheral hooks26A,26B,26C, and26D as hook portions at intervals of approximately 90 degrees about the rotation axis O. The four outer peripheral hooks26A,26B,26C, and26D are provided corresponding to the four outer peripheral protruding portions22A,22B,22C, and22D of the retainer plate22, respectively. That is, the four outer peripheral hooks26A,26B,26C, and26D and the four outer peripheral protruding portions22A,22B,22C, and22D are provided at the same relative angles, and the relative angles of the four outer peripheral hooks26A,26B,26C, and26D match the relative angles of the four outer peripheral protruding portions22A,22B,22C, and22D. The torsion spring28is located in the clearance in the circumferential direction between each of corresponding portions1A,1B,1C, and1D in which the four outer peripheral hooks26A,26B,26C, and26D face the four outer peripheral protruding portions22A,22B,22C, and22D, respectively, and each inner peripheral protruding portion of the intermediate plate27. For example, the first torsion spring S1is located in the clearance in the circumferential direction between the corresponding portion1A and the inner peripheral protruding portion27P. The second torsion spring S2is located in the clearance in the circumferential direction between the corresponding portion1A and the inner peripheral protruding portion27Q.

In the first corresponding portions1A,1C that are a part of the corresponding portions1A,1B,1C and1D, the torsion springs28are separated from the outer peripheral hooks26A,26C of the output plate26and in contact with the outer peripheral protruding portions22A,22C of the retainer plate22. For example, in the first corresponding portion1A, both the other end of the first torsion spring S1and the other end of the second torsion spring S2are separated from the outer peripheral hook26A and in contact with the outer peripheral protruding portion22A of the retainer plate22. As described above, in the first corresponding portion1A, the first torsion spring S1and the second torsion spring S2that are in contact with the outer peripheral protruding portion22A sandwich the retainer plate22therebetween even when the side surfaces in the circumferential direction of the outer peripheral protruding portion22A and the side surfaces in the circumferential direction of the outer peripheral hook26A are not planar. The first corresponding portion1C is similar to the first corresponding portion1A. Since each of the outer peripheral protruding portions22A,22C is thus supported by two torsion springs28, backlash in the circumferential direction of the retainer plate22can be reduced.

On the other hand, in the second corresponding portions1B,1D that are the remainder of the corresponding portions1A,1B,1C and1D, the torsion springs28are separated from the outer peripheral protruding portions22B,22D of the retainer plate22and in contact with the outer peripheral hooks26B,26D of the output plate26. For example, in the second corresponding portion1B, both the other end of the third torsion spring S3and the other end of the fourth torsion spring S4are separated from the outer peripheral protruding portion22B of the retainer plate22and in contact with the outer peripheral hook26B of the output plate26. As described above, in the second corresponding portion1B as well, the third torsion spring S3and the fourth torsion spring S4that are in contact with the outer peripheral hook26B sandwich the output plate26therebetween even when the side surfaces in the circumferential direction of the outer peripheral protruding portion22B and the side surfaces in the circumferential direction of the outer peripheral hook26B are not planar. The second corresponding portion1D is similar to the second corresponding portion1B. Since each of the outer peripheral hooks26B,26D is thus supported by two torsion springs28, backlash in the circumferential direction of the output plate26can be reduced.

That is, backlash in the circumferential direction of both the retainer plate22and the output plate26can be reduced even when the side surfaces in the circumferential direction of the outer peripheral protruding portion22A and the outer peripheral hook26A, the side surfaces in the circumferential direction of the outer peripheral protruding portion22B and the outer peripheral hook26B, etc. are not planar. The same applies to the remaining outer peripheral protruding portions22C,22D and the remaining outer peripheral hooks26C,26D.

When torque is input to the piston plate21in a stationary state in which no torque is input to the piston plate21and the retainer plate22is stationary as shown inFIGS.2and3A, the state is shifted to a rotating state in which the retainer plate22is rotated, as shown inFIG.3B. When shifted to the rotating state, the outer peripheral protruding portion22A of the retainer plate22moves in the circumferential direction as shown by arrow R. As a result, the outer peripheral protruding portion22A presses the second torsion spring S2. As the outer peripheral protruding portion22A moves, the other end of the first torsion spring S1that is in contact with the outer peripheral protruding portion22A then comes into contact with the outer peripheral hook26A. InFIGS.3A and3B, the first torsion spring S1and the second torsion spring S2are not illustrated in detail for better understanding of this function.

In the above rotating state, a winding end and polished end of the first torsion spring S1according to the present embodiment are located at such positions that achieve contact between a spring body of the first torsion spring S1, that is, the first torsion spring S1other than the winding end and the polished end, and the outer peripheral hook26A of the output plate26. The polished end according to the present embodiment is an end face of the torsion spring28polished into a plane perpendicular to the axis of the torsion spring28.

Specifically, when the outer peripheral hook26A is viewed from the side surface as shown by arrow IV A inFIG.3B, the outer peripheral hook26A of the output plate26is bent in the direction toward the outer peripheral protruding portion22A as shown inFIG.4A. A winding end E1and polished end E2of the first torsion spring S1are located at first predetermined positions that achieve contact between a spring body Sb of the first torsion spring S1and a hook edge26N located at the tip end of the bent outer peripheral hook26A. As a result, even when shifted to the rotating state, the spring body Sb and the hook edge26N are in stable contact with each other as shown by broken circle C1. Accordingly, the positions of the retainer plate22and the output plate26can be stabilized as compared to the case where the winding end E1and the polished end E2are not located at the first predetermined positions. The spring body Sb of the first torsion spring S1is an example of a first main body of the first elastic body, and the winding end E1and the polished end E2of the first torsion spring S1are examples of the first elastic body end.

A winding end and polished end of the second torsion spring S2according to the present embodiment are also located at such positions that achieve contact between a spring body of the second torsion spring S2and the outer peripheral protruding portion22A of the retainer plate22in the above rotating state.

Specifically, when the outer peripheral protruding portion22A is viewed from the side surface as shown by arrow IVB inFIG.3B, a part of the outer peripheral protruding portion22A of the retainer plate22is bent in a U shape as shown inFIG.4B. A winding end E3and polished end E4of the second torsion spring S2are located at second predetermined positions that achieve contact between a spring body Sb of the second torsion spring S2and a U-shaped part22N that is located closer to the rotation axis than the hook edge26N of the outer peripheral protruding portion22A. As a result, even when shifted to the rotating state, the spring body Sb and the U-shaped part22N are in stable contact with each other as shown by broken circles C2, C3. Accordingly, the positions of the retainer plate22and the output plate26can be stabilized as compared to the case where the winding end E3and the polished end E4are not located at the second predetermined positions. The spring body Sb of the second torsion spring S2is an example of a second main body of the second elastic body, and the winding end E3and the polished end E4of the second torsion spring S2are examples of the second elastic body end.

For example, as shown by a comparative example ofFIG.5, when the winding end E1and the polished end E2are not located at the first predetermined positions, or when the winding end E3and the polished end E4are not located at the second predetermined positions, the positions of the retainer plate22and the output plate26are not stabilized and the unbalance (rotational balance) phase of the retainer plate22and the output plate26changes, depending on the number of measurements.

However, as shown by the embodiment ofFIG.5, when the winding end E1and the polished end E2are located at the first predetermined positions, or when the winding end E3and the polished end E4are located at the second predetermined positions, the positions of the retainer plate22and the output plate26are stabilized and the unbalance (rotational balance) phase of the retainer plate22and the output plate26does not change, regardless of the number of measurements.

Although the embodiment of the present disclosure is described in detail above, the present disclosure is not limited to the specific embodiment, and various modifications and variations can be made within the spirit and scope of the present disclosure described in the claims.

For example, the two first corresponding portions1A,1C and the two second corresponding portions1B,1D are described in the above embodiment. However, six outer peripheral hooks and six outer peripheral protruding portions may be provided corresponding to each other. In this case, the outer peripheral hooks and the outer peripheral protruding portions are located at intervals of 60 degrees, and the number of first corresponding portions and the number of second corresponding portions can be the same, namely three. In the above embodiment, the damper device1is mounted inside the torque converter2. However, for example, the damper device1may be mounted outside the torque converter2or may be mounted in other power transmission unit of a vehicle that does not use the torque converter2.