阅读说明：本技术 减振装置 (Vibration damping device ) 是由 冨田雄亮 冈町悠介 于 2020-03-10 设计创作，主要内容包括：本发明提供一种减振装置,其具备用于使两个扭转弹簧串联地工作的中间旋转体,抑制中间旋转体因共振而大幅振动。该减振装置(3)具备输入侧旋转体(20)、输出侧旋转体(21)、多个扭转弹簧(22)、中间旋转体(23)和迟滞产生部(24b)。输出侧旋转体(21)能够与输入侧旋转体(20)相对旋转。多个扭转弹簧(22)将输入侧旋转体(20)和输出侧旋转体(21)在圆周方向上弹性地连结。中间旋转体(23)能够与输入侧旋转体(20)及输出侧旋转体(21)相对旋转,使多个扭转弹簧(22)中的至少两个串联地工作。迟滞产生部(24b)在扭转弹簧(22)的弹性变形时对中间旋转体(23)赋予迟滞扭矩。(The invention provides a vibration damping device which is provided with an intermediate rotating body for enabling two torsion springs to work in series and restrains the intermediate rotating body from greatly vibrating due to resonance. The vibration damping device (3) is provided with an input-side rotating body (20), an output-side rotating body (21), a plurality of torsion springs (22), an intermediate rotating body (23), and a hysteresis generating unit (24 b). The output-side rotating body (21) can rotate relative to the input-side rotating body (20). The torsion springs (22) elastically connect the input-side rotating body (20) and the output-side rotating body (21) in the circumferential direction. The intermediate rotating body (23) can rotate relative to the input-side rotating body (20) and the output-side rotating body (21), and at least two of the plurality of torsion springs (22) are operated in series. The hysteresis generating section (24b) imparts a hysteresis torque to the intermediate rotating body (23) when the torsion spring (22) is elastically deformed.)

1. A vibration damping device for transmitting power from a power source to an output-side member, the vibration damping device comprising:

an input-side rotating body configured to be rotatable, power from a power source being input to the input-side rotating body;

an output-side rotating body that is rotatable relative to the input-side rotating body;

a plurality of elastic members that elastically connect the input-side rotating body and the output-side rotating body in a circumferential direction;

an intermediate rotating body that is relatively rotatable with respect to the input-side rotating body and the output-side rotating body and that causes at least two of the plurality of elastic members to operate in series; and

and a first hysteresis generating mechanism for applying a hysteresis torque to the intermediate rotating body when the elastic member is elastically deformed.

2. The vibration damping device according to claim 1,

the first hysteresis generating mechanism generates a hysteresis torque between the output-side rotating body and the intermediate rotating body.

3. The vibration damping device according to claim 1 or 2,

the first hysteresis generating mechanism has:

a ring plate fixed to the output-side rotating body and in sliding contact with a side surface of the intermediate rotating body; and

and a force application member for pressing the annular plate against a side surface of the intermediate rotating body.

4. The vibration damping device according to claim 3,

the vibration damping device further includes a second hysteresis generating mechanism that generates a hysteresis torque between the input-side rotating body and the output-side rotating body.

5. The vibration damping device according to claim 4,

the second hysteresis generating mechanism has a friction plate fixed to the input-side rotating body and in sliding contact with the annular plate,

the friction plate is pressed against the annular plate by the urging member.

6. The vibration damping device according to claim 3,

the output-side rotating body includes:

a hub coupled to the output-side member; and

a plurality of flanges provided so as to extend radially outward from the hub and arranged at predetermined intervals in a circumferential direction,

the intermediate rotating body includes:

an annular portion; and

an intermediate flange provided to extend radially outward from the annular portion and disposed at least at one location between a plurality of flanges of the output-side rotating body in a circumferential direction, the intermediate flange being configured to operate at least two elastic members of the plurality of elastic members in series,

the annular plate is fixed to the plurality of flanges and is in sliding contact with the intermediate flange.

7. The vibration damping device according to claim 6,

the first hysteresis generating mechanism is disposed between the hub of the output-side rotating body and the elastic member in the radial direction.

Technical Field

The present invention relates to a vibration damping device, and more particularly to a vibration damping device for transmitting power from a power source to an output-side member.

Background

Various devices are mounted in a vehicle drive system to transmit power generated by an engine to a transmission. Examples of such devices include a damper device and a flywheel assembly. In these devices, a vibration damping mechanism as shown in patent document 1 is used for the purpose of damping rotational vibration.

The vibration damping device of patent document 1 includes an input plate, an output plate, a plurality of springs, and an intermediate plate. The output plate is configured to be rotatable relative to the input plate. The intermediate plate engages with the low-stiffness spring and the high-stiffness spring, and connects the low-stiffness spring and the high-stiffness spring in series.

Patent document 1: japanese patent laid-open No. 2015-161371

In the intermediate plate of patent document 1, two springs are connected in series, so that the torsion angles of the input plate and the output plate can be set to a wide angle. Therefore, the vibration damping performance can be improved.

However, in the device provided with the intermediate plate as in patent document 1, depending on the rotation speed of the engine, the intermediate plate may resonate and the intermediate plate may vibrate largely.

Disclosure of Invention

The present invention is directed to a vibration damping device including an intermediate rotating body for operating two elastic bodies in series, the vibration damping device being configured to suppress a large vibration of the intermediate rotating body due to resonance.

(1) The vibration damping device according to the present invention is a device that transmits power from a power source to an output-side member. The vibration damping device includes an input-side rotating body, an output-side rotating body, a plurality of elastic members, an intermediate rotating body, and a first hysteresis generating mechanism. The input-side rotating body is arranged to be rotatable, and power from the power source is input to the input-side rotating body. The output-side rotating body is rotatable relative to the input-side rotating body. The plurality of elastic members elastically connect the input-side rotating body and the output-side rotating body in the circumferential direction. The intermediate rotating body is capable of rotating relative to the input-side rotating body and the output-side rotating body, and at least two elastic members of the plurality of elastic members are operated in series. The first hysteresis generating mechanism imparts a hysteresis torque to the intermediate rotating body when the elastic member is elastically deformed.

In this device, when power is input to the input-side rotating body, the power is transmitted from the input-side rotating body to the output-side rotating body via the elastic member. During this operation, the elastic member expands and contracts, thereby causing relative rotation between the input-side rotating body, the output-side rotating body, and the intermediate rotating body. At this time, the first hysteresis generating mechanism applies a hysteresis torque to the intermediate rotating body.

Here, the first hysteresis generating mechanism applies a hysteresis torque to the intermediate rotating body, and therefore resonance of the intermediate rotating body can be suppressed.

(2) Preferably, the first hysteresis generating mechanism generates a hysteresis torque between the output-side rolling body and the intermediate rolling body.

(3) Preferably, the first hysteresis generating mechanism has an annular plate and a force application member. The annular plate is fixed to the output-side rotating body and is in sliding contact with the side surface of the intermediate rotating body. The urging member presses the annular plate against the side surface of the intermediate rotating body.

Here, a hysteresis torque is generated between the annular plate fixed to the output-side rolling body and the intermediate rolling body. Therefore, for example, even when the output-side rotating body does not have an annular friction surface, a continuous friction surface can be formed by the annular plate, and the surface pressure of the friction surface can be reduced and abnormal wear of the friction portion can be suppressed.

(4) Preferably, the hybrid vehicle further includes a second hysteresis generating mechanism that generates a hysteresis torque between the input-side rotating body and the output-side rotating body.

(5) Preferably, the second hysteresis generating mechanism has a friction plate fixed to the input-side rotating body and in sliding contact with the annular plate. The friction plate is pressed against the annular plate by the urging member.

Here, the friction plate fixed to the input-side rotating body is pressed against the annular plate fixed to the output-side rotating body, and a hysteresis torque is generated therebetween.

(6) Preferably, the output-side rotating body has a hub coupled to the output-side member and a plurality of flanges. The flanges are provided so as to extend radially outward from the hub and are arranged at predetermined intervals in the circumferential direction. In addition, preferably, the intermediate rotating body has an annular portion and an intermediate flange. The intermediate flange is provided to extend radially outward from the annular portion. The intermediate flange is disposed at least at one position between the plurality of flanges of the output-side rotating body in the circumferential direction, and at least two elastic members of the plurality of elastic members are operated in series. In addition, the annular plate is fixed to the plurality of flanges and is in sliding contact with the intermediate flange.

(7) Preferably, the first hysteresis generating mechanism is disposed between the hub of the output-side rotating body and the elastic member in the radial direction.

Effects of the invention

In the vibration damping device including the intermediate rotating body for operating the two elastic bodies in series according to the present invention as described above, it is possible to suppress the intermediate rotating body from largely vibrating due to resonance.

Drawings

Fig. 1 is a sectional view of a power transmission device including a vibration damping device according to an embodiment of the present invention.

Fig. 2 is an extracted diagram showing the torque limiting device of fig. 1.

Fig. 3 is an extracted view showing the vibration damping device of fig. 1.

Fig. 4 is a diagram showing the hysteresis generating mechanism of fig. 1.

Fig. 5 is a front view showing a part of the vibration damping device of fig. 1 removed.

Fig. 6 is an external view of the hysteresis generating mechanism.

Fig. 7 is a diagram showing the magnitude of vibration caused by resonance of the intermediate rotating body and the magnitude of vibration in the present embodiment.

Description of the reference numerals

3, a vibration damping device; 20 an input-side rotating body; 21 an output-side rotating body; 22 a torsion spring; 23 an intermediate rotating body; a 24 hysteresis generating mechanism; 35a hub; 36 flanges; 40 annular portion 41 intermediate flange; 45 circular ring plates; 46a friction plate; a 47 conical spring.

Detailed Description

Fig. 1 is a sectional view of a power transmission device 1 having a vibration damping device according to an embodiment of the present invention, and fig. 2 is a front view showing a part thereof removed. The power transmission device 1 is mounted on, for example, a hybrid vehicle. The power transmission device 1 includes a torque limiter device 2 and a damper device 3 to which power from an engine is input via the torque limiter device 2. An engine is disposed on the right side of fig. 1, and a motor, a transmission, and the like are disposed on the left side. The O-O line of FIG. 1 is the axis of rotation.

[ Torque-limiting device 2]

The torque limiter device 2 is coupled to a flywheel 4 to which power is input from the engine. Therefore, for example, when an excessive torque is input from the output side, the transmitted torque is limited to a predetermined value or less so as not to transmit the excessive torque to the engine side. The torque limiting device 2 has a cover 10, a damping plate 11, a friction disc 12, a pressure plate 13, and a conical spring 14. The friction disk 12, the pressure plate 13, and the conical spring 14 are housed inside the cover 10.

Fig. 2 shows the torque limiting device 2 in an enlarged manner. The cover 10 has a coupling portion 10a, a cylindrical portion 10b, and a support portion 10 c. The coupling portion 10a, the cylindrical portion 10b, and the support portion 10c are integrally formed by press forming. Therefore, the cylindrical portion 10b has a slope formed by drawing, and is inclined toward the inner peripheral side as it is separated from the flywheel 4. Further, a curved portion 10d is formed between the cylindrical portion 10b and the support portion 10 c.

The coupling portion 10a is formed in a ring shape, and is coupled to the flywheel 4 with the damper plate 11 interposed therebetween by a bolt 15. The cylindrical portion 10b extends from the inner peripheral end of the coupling portion 10a to the output side (the side away from the flywheel 4). The support portion 10c is annular and extends from the front end of the cylindrical portion 10b to the inner circumferential side by a predetermined width. An annular support protrusion 10e protruding toward the flywheel 4 is formed at a radially intermediate portion of the support portion 10 c.

The damper plate 11 is formed in a ring shape and has a plurality of holes 11a in an outer peripheral portion. The damper plate 11 is fixed to the side surface of the flywheel 4 together with the cover 10 by bolts 15 penetrating the holes 11 a. The outer diameter is the same as the outer diameter of the flywheel 4, and the inner diameter is smaller than the inner diameter of a friction material (described later) of the friction disk 12.

The friction disc 12 has a core plate 17 and a pair of friction members 18. The core plate 17 is formed in a ring shape and has a plurality of fixing portions 17a extending further radially inward from the inner peripheral end. The core plate 17 is coupled to the damper device 3 via the fixing portion 17 a. A pair of friction members 18 are formed in a ring shape and fixed to both side surfaces of the core plate 17.

The pressure plate 13 is formed in an annular shape and is disposed to face the damper plate 11 through the friction disk 12. That is, the friction disk 12 is sandwiched between the damper plate 11 and the pressure plate 13. The inner diameter of the pressure plate 13 is smaller than the inner diameter of the friction members 18 of the friction disc 12.

The conical spring 14 is disposed in a compressed state between the pressure plate 13 and the support portion 10c of the cover 10. The outer peripheral portion of the conical spring 14 is supported by the supporting projection 10e of the supporting portion 10c, and the inner peripheral end abuts against the pressure plate 13, pressing the pressure plate 13 toward the flywheel 4.

With such a torque limiter device 2, when the torque transmitted between the engine side and the damper device 3 exceeds the torque transmission capacity set by the torque limiter device 2, a slip occurs locally at the friction disk 12, and the transmitted torque is limited.

In the torque limiter device 2, the cylindrical portion 10b of the cover 10 has a gradient on the inner peripheral side as it becomes farther from the flywheel 4. Therefore, the diameter of the inner peripheral surface of the output-side end portion of the cylindrical portion 10b is smaller than that of the flywheel 4-side end portion. In addition, a curved surface portion 10d is formed at an end portion of the cylindrical portion 10 b. Therefore, if the friction disk 12 is disposed on the support portion 10c side, the diameter of the friction disk 12 cannot be secured large.

However, in the present embodiment, since the friction disk 12 is disposed on the flywheel 4 side inside the cover 10, the diameter of the friction disk 12 can be set to a larger diameter without being affected by the gradient of the cylindrical portion 10 b. In contrast, the diameter of the torque limiter device 2 having the same torque transmission capacity can be miniaturized.

In the present embodiment, the friction disk 12 is arranged to be pressed against the flywheel 4 through the damper plate 11. If the friction disk 12 is disposed on the support portion 10c side of the cover 10 and the conical spring 14 is disposed on the flywheel 4 side, contrary to the present embodiment, the inner peripheral side of the support portion 10c of the cover 10 is elastically deformed so as to open outward. Then, the friction material 18 of the friction disk 12 comes into uneven contact with the support portion 10c, and a desired torque capacity may not be obtained or the friction material 18 may be abnormally worn. Then, in order to avoid such a problem, the thickness of the plate member constituting the cover 10 needs to be increased.

However, in this embodiment, the friction disk 12 is disposed on the flywheel 4 side, and the conical spring 14 is disposed on the support portion 10c side of the cover 10, so that the surface (side surface of the damper plate 11) that abuts against the friction disk 12 is less likely to deform. Therefore, the entire friction members 18 of the friction disk 12 are uniformly in contact with the damping plate 11, and a stable torque capacity can be obtained. In addition, abnormal wear of the friction members 18 of the friction disk 12 can be suppressed.

Here, although the support portion 10c of the cover 10 is also elastically deformed in the present embodiment, this elastic deformation acts as a force pressing the friction disk 12 together with the biasing force of the conical spring 14. Therefore, the thickness of the plate member constituting the lid 10 can be made thin. Therefore, the torque limiter device 2 can be downsized in the axial direction.

In the torque limiter device 2 having the above-described configuration, the torque limiter device 2 can be easily attached to a general-purpose flywheel, that is, a flywheel that does not have a special shape for attaching a torque limiter.

[ damping device 3]

The damper device 3 transmits the power from the torque limiter device 2 to the output side, and damps the vibration during power transmission. The vibration damping device 3 is extracted as shown in fig. 3. The damper device 3 includes an input-side rotating body 20, an output-side rotating body 21, a plurality of torsion springs 22, an intermediate rotating body 23, and a hysteresis generating mechanism 24.

< input-side rotating body 20>

The input-side rotating body 20 is rotatable about a rotation axis and has a first plate 31 and a second plate 32.

The first plate 31 includes a disc portion 31a, a plurality of first window portions 31b for holding the torsion spring 22, a plurality of bent portions 31c, and a plurality of fixing portions 31d (see fig. 4). Fig. 4 shows a cross section of the vibration damping device 3 at a different circumferential position from that of fig. 1. The first plate 31 is positioned in the radial direction by the inner peripheral surface of the disk portion 31a and the outer peripheral surface of a cylindrical hub (described later) of the output-side rotating body 21.

The first window 31b is formed in the outer peripheral portion of the disk portion 31 a. The first window portion 31b has a circumferentially long hole penetrating in the axial direction, and a holding portion formed on the inner and outer peripheries of the hole and holding the torsion spring 22. The circumferential end surface of the hole can abut against the end surface of the torsion spring 22.

The bent portion 31c has an L-shaped cross section and is formed by bending the outer peripheral end of the disk portion 31a toward the flywheel 4. The rotational strength of the first plate 31 is improved by bending the outer peripheral end portion of the disk portion 31a into an L-shaped cross section.

As shown in fig. 4 and 5, the fixing portion 31d is formed by bending the distal end of the bent portion 31c further radially inward at the center portion in the circumferential direction of the bent portion 31 c. Fig. 5 is a front view showing a device with a part of its components removed. Further, a hole 31e for rivet fixing is formed in the fixing portion 31 d. A hole 31f for rivet fastening is formed in the disk portion 31a at the same position as the hole 31e for rivet fastening.

The second plate 32 is disposed axially opposite the first plate 31 on the flywheel 4 side of the first plate 31. The second plate 32 is formed in a disk shape and has a plurality of second windows 32 b. The second plate 32 is positioned in the radial direction by its inner circumferential surface and an outer circumferential surface of a cylindrical hub (described later) of the output-side rotating body 21.

The second window portion 32b is formed at a position corresponding to the first window portion 31b of the first plate 31. The second window portion 32b has a circumferentially long hole penetrating in the axial direction, and a holding portion formed on the inner and outer peripheries of the hole and holding the torsion spring 22. The circumferential end surface of the hole can abut against the end surface of the torsion spring. The torsion spring 22 is held by the second window portion 32b and the first window portion 31b of the first plate 31.

The second plate 32 has a hole 32e for rivet fixing at the same position as the hole 31e for rivet fixing of the first plate 31. The first plate 31 and the second plate 32 are fixed so as not to be movable in the axial direction and the circumferential direction by rivets 33 that penetrate through holes 31e, 32e for rivet fixing of the first plate 31 and the second plate 32. The fixing portion 17a of the core plate 17 of the friction disk 12 is inserted between the fixing portion 31d of the first plate 31 and the second plate 32, and the first plate 31 and the second plate 32 are fixed to the friction disk 12.

< output-side rotating body 21>

The output-side rotating body 21 is disposed between the first plate 31 and the second plate 32 in the axial direction. The output-side rotating body 21 is rotatable about a rotation axis and is rotatable relative to the first plate 31 and the second plate 32. The output-side rolling body 21 has a hub 35 and three flanges 36.

The hub 35 is disposed in the center of the output side rotor 21 and has a cylindrical shape. A spline hole 35a is formed in the inner peripheral portion, and the spline hole 35a is spline-coupled to a shaft (not shown) formed on the output side. As described above, the outer peripheral surface of the hub 35 and the inner peripheral surfaces of the first plate 31 and the second plate 32 position the first plate 31 and the second plate 32 in the radial direction with respect to the hub 35.

Three flanges 36 are formed to radially extend from the outer circumferential surface of the hub 35. The three flanges 36 are arranged at equal angular intervals in the circumferential direction. The flange 36 has a hysteresis mechanism mounting portion 36a, a first support portion 36b, and a second support portion 36 c. The hysteresis mechanism mounting portion 36a is a flat surface and is formed on the outer peripheral side of the hub 35. The first support portion 36b extends radially outward from the hysteresis mechanism mounting portion 36a, and is smaller in width in the circumferential direction than the hysteresis mechanism mounting portion 36 a. The spring seat 38 abuts both end surfaces in the circumferential direction of the first support portion 36 b. The second support portion 36c is formed by extending both end portions of the outer peripheral end of the first support portion 36b in the circumferential direction. The spring seat 38 abuts against the inner peripheral surface of the second support portion 36 c.

The second support portion 36c is disposed at the same position in the radial direction as the fixing portion 31d of the first plate 31. A hole 36d penetrating in the axial direction is formed in the second support portion 36 c. The first plate 31 and the second plate 32 are riveted through the hole 36d and the hole 31f for riveting the first plate 31.

< torsion spring 22>

The torsion spring 22 is accommodated between the plurality of flanges 36 of the output side rotating body 21 in the circumferential direction, and is held by the first window portion 31b and the second window portion 32b of the first plate 31 and the second plate 32. Two torsion springs 22 are disposed between the adjacent flanges 36, and spring seats 38 are disposed on both end surfaces of each torsion spring 22.

< intermediate rotating body 23>

The intermediate rotating body 23 is rotatable about a rotation axis and is rotatable relative to the first plate 31, the second plate 32, and the output-side rotating body 21. The intermediate rotating body 23 is a member for operating the two torsion springs 22 arranged between the adjacent flanges 36 in series. The intermediate rotating body 23 has an annular portion 40 and three intermediate flanges 41.

The inner peripheral portion of the annular portion 40 is inserted into the outer periphery of the hub 35 of the output side rotating body 21. That is, the intermediate rotating body 23 is positioned in the radial direction with respect to the output side rotating body 21 by the inner peripheral surface of the annular portion 40 contacting the outer peripheral surface of the hub 35. The annular portion 40 is arranged axially side by side with the flange 36 on the flywheel 4 side of the flange 36 of the output-side rotating body 21.

The three intermediate flanges 41 have an offset portion 41a, a friction portion 41b, a first support portion 41c, a second support portion 41d, and a stopper portion 41 e.

As shown in fig. 3 and 5, the offset portion 41a is a portion connecting the annular portion 40 and the friction portion 41 b. Here, both side surfaces of the friction portion 41b are at the same axial positions as both side surfaces of the flange 36 of the output side rotator 21. That is, the friction portion 41b and the side surface of the flange 36 of the output-side rotator 21 on the flywheel 4 side are located on one plane. In addition, the friction portion 41b and the side surface on the output side of the flange 36 of the output side rotator 21 are located on one plane. The offset portion 41a connects the annular portion 40 and the friction portion 41b at different axial positions.

The first support portion 41c extends radially outward from the friction portion 41b, and is smaller in width in the circumferential direction than the friction portion 41 b. The spring seat 38 abuts both end surfaces in the circumferential direction of the first support portion 41 c. The second support portion 41d is formed by extending both end portions of the outer peripheral end of the first support portion 41c in the circumferential direction. The spring seat 38 abuts against the inner peripheral surface of the second support portion 41 d.

The stopper portion 41e is formed at the circumferential center portion of the outer peripheral surface of the first support portion 41c and projects radially outward. The stopper portion 41e is disposed at the center in the circumferential direction of the adjacent bent portion 31c of the first plate 31. Then, the circumferential end surface of the stopper portion 41e can abut against the circumferential end surface of the bent portion 31 c.

That is, the relative rotation angle between the input-side rotating body 20 and the intermediate rotating body 23 (and further the output-side rotating body 21) is restricted within a predetermined angular range by the bent portion 31c of the first plate 31 and the stopper portion 41e of the intermediate rotating body 23.

[ hysteresis generating mechanism 24]

The hysteresis generating mechanism 24 is disposed radially between the hub 35 of the output-side rotator 21 and the torsion spring 22. Further, the damper is disposed between the flange 36 (specifically, the hysteresis mechanism mounting portion 36a) of the output side rotating body 21 and the intermediate flange 41 (specifically, the friction portion 41b) of the intermediate rotating body 23 and the first plate 31, and between the flange 36 of the output side rotating body 21 and the intermediate flange 41 of the intermediate rotating body 23 and the second plate 32 in the axial direction.

As shown in fig. 4 and 6, the hysteresis generating mechanism 24 has two circular ring plates 45, two friction plates 46, and a conical spring 47. Since the two annular plates 45 and the two friction plates 46 are different in size, the annular plate 45 and the friction plate 46 on the first plate 31 side will be described here. Fig. 6 shows a part of the output-side rotor 21, the intermediate rotor 23, and the hysteresis generating mechanism 24.

The annular plate 45 is formed in an annular shape and abuts against the side surfaces of the output-side rotating body 21 and the intermediate rotating body 23. The annular plate 45 is fixed to the hysteresis mechanism mounting portion 36a of the output side rotating body 21. Therefore, the ring plate 45 cannot rotate relative to the output side rotator 21, but can rotate relative to the intermediate rotator 23. Although not described in detail here, the annular plate 45 is provided with a plurality of fixing portions protruding toward the inner circumferential side and fixed to the output side rotating body 21 by rivets or the like, for example.

The friction plate 46 is formed in a ring shape, and a side surface on the flywheel side abuts against the ring plate 45 while the other surface abuts against the first plate 31. Further, a plurality of engaging projections 46a projecting in the axial direction are formed on the surface of the friction plate 46 on the first plate 31 side. Then, the engaging projection 46a engages with the hole 31g formed in the first plate 31. Thus, the friction plate 46 cannot rotate relative to the first plate 31, but can rotate relative to the annular plate 45.

As described above, the annular plate 45 and the friction plate 46 on the second plate 32 side have the same configuration. Further, a conical spring 47 is mounted in a compressed state between the friction plate 46 on the second plate 32 side and the second plate 32.

With the above configuration, when the input-side rotor 20 and the output-side rotor 21 rotate relative to each other and the torsion spring 22 expands and contracts, frictional resistance (hysteresis torque) is generated between the friction plate 46 and the annular plate 45. When the torsion spring 22 expands and contracts and the output side rotary body 21 and the intermediate rotary body 23 rotate relative to each other, a hysteresis torque is similarly generated. That is, the hysteresis generating mechanism 24 includes a hysteresis generating unit 24a (see fig. 4) that generates a hysteresis torque between the input-side rotator 20 and the output-side rotator 21, and a hysteresis generating unit 24b (see fig. 3) that applies a hysteresis torque to the intermediate rotator 23.

[ actions ]

The power transmitted from the engine to the flywheel 4 is input to the damper device 3 via the torque limiter device 2. In the damper device 3, power is input to the first plate 31 and the second plate 32 of the friction disk 12 to which the torque limiter device 2 is fixed, and the power is transmitted to the output side rotating body 21 via the torsion spring 22. Then, the power is further transmitted from the output side rotation body 21 to the output side motor, generator, transmission, and the like.

Further, for example, at the time of starting the engine, an excessive torque may be transmitted from the output side to the engine because the inertia amount on the output side is large. In this case, the torque transmitted to the engine side is limited to a predetermined value or less by the torque limiting device 2.

In the damper device 3, when power is transmitted from the first plate 31 and the second plate 32 to the torsion spring 22, the torsion spring 22 is compressed. Further, the torsion spring 22 repeatedly expands and contracts due to the torque variation. When the torsion spring 22 expands and contracts, torsion occurs between the first plate 31 and the second plate 32 and the output-side rotating body 21.

The hysteresis generating mechanism 24 is operated by the torsion between the first plate 31 and the second plate 32 and the output-side rotator 21, and generates a hysteresis torque. Specifically, since relative rotation is generated between the friction plate 46 fixed to the first plate 31 and the second plate 32 and the annular plate 45 fixed to the output-side rotator 21, frictional resistance is generated therebetween. This generates a hysteresis torque between the first and second plates 31 and 32 and the output-side rotator 21.

Further, the torsion spring 22 expands and contracts to cause torsion between the output-side rotating body 21 and the intermediate rotating body 23. Due to this twisting, relative rotation occurs between the annular plate 45 fixed to the output side rotary body 21 and the friction portion 41b of the intermediate rotary body 23, and therefore frictional resistance occurs therebetween. This generates a hysteresis torque between the output-side rolling element 21 and the intermediate rolling element 23.

Depending on the engine speed, the intermediate rotating body 23 may vibrate largely due to resonance. However, in this embodiment, the large-amplitude vibration of the intermediate rotor 23 due to resonance can be suppressed by the hysteresis torque between the output-side rotor 21 and the intermediate rotor 23.

Fig. 7 is a diagram showing the magnitude of vibration of the intermediate rotating body 23. The broken line M in fig. 7 indicates that no hysteresis torque is applied to the intermediate rotator 23, and the solid line M in the same figure indicates that hysteresis torque is applied to the intermediate rotator 23. As is clear from this figure, the magnitude of vibration due to resonance can be suppressed by applying a hysteresis torque to the intermediate rotating body 23.

When the torsion angles of the first plate 31 and the second plate 32 with respect to the output-side rotating body 21 and the intermediate rotating body 23 increase, the end surface of the bent portion 31c of the first plate 31 comes into contact with the end surface of the stopper portion 41e of the intermediate rotating body 23. Therefore, the torsion angles of the first plate 31 and the second plate 32 with respect to the output-side rotating body 21 and the intermediate rotating body 23 can be suppressed from becoming equal to or larger than a predetermined angle. Therefore, excessive stress can be prevented from acting on the torsion spring 22.

[ other embodiments ]

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

(a) In the above embodiment, the hysteresis generating mechanism 24 is provided with the annular plate 45 and the friction plate 46, but the friction plate may be in direct contact with the output-side rotator 21 and the intermediate rotator 23.

(b) In the above embodiment, the hysteresis torque is generated between the input side rotating body 20 and the output side rotating body 21, but the hysteresis generating portion 24a between the input side rotating body 20 and the output side rotating body 21 can be omitted depending on the specifications of the vehicle.