Power transmission device

Abstract

To suppress wear of a portion coming into contact with a disc spring.SOLUTION: A power transmission device includes a first rotary member, a second rotary member, a friction member, and a biasing mechanism. The second rotary member is disposed so as to be rotatable relative to the first rotary member. The friction member is disposed between the first rotary member and the second rotary member in an axial direction. The biasing mechanism biases the friction member toward the first rotary member or the second rotary member. The biasing mechanism includes: a first disc spring; and a second disc spring stacked on the first disc spring in series.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a power transmission device. [Background technology]

[0002] A damper device, which is an example of a power transmission device, includes an input rotary member, an output rotary member, and a plurality of elastic members (see, for example, Patent Document 1). Each elastic member elastically connects the input rotary member to the output rotary member. An input shaft of a transmission or the like is spline-fitted to the output rotary member.

[0003] In addition, to suppress resonance, the damper device has a friction member and a disc spring. The friction member and the disc spring are arranged between the input rotary member and the output rotary member. The disc spring urges the friction member toward the output rotary member. The friction member frictionally engages with the output rotary member, thereby suppressing resonance. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-227222 Summary of the Invention [Problem to be solved by the invention]

[0005] In the power transmission device configured as described above, there is a problem in that the portion in contact with the disc spring wears. Therefore, an object of the present invention is to suppress the wear of the portion in contact with the disc spring. [Means for solving the problem]

[0006] As a result of extensive research, the inventors have found that the axial movement of an input shaft of a transmission or the like causes significant wear at the contact point with the disc spring. Specifically, when the input shaft of a transmission or the like moves axially, the amount of movement can exceed the total deflection of the disc spring. As a result, when the disc spring is fully deflected, a large load is applied to the contact point with the disc spring, causing significant wear at the contact point.

[0007] In order to suppress the above-described wear, a power transmission device according to a first aspect is configured as follows. The power transmission device includes a first rotating member, a second rotating member, a friction member, and a biasing mechanism. The second rotating member is arranged to be rotatable relative to the first rotating member. The friction member is arranged axially between the first rotating member and the second rotating member. The biasing mechanism biases the friction member toward the first rotating member or the second rotating member. The biasing mechanism includes a first disc spring and a second disc spring stacked in series on the first disc spring.

[0008] With this configuration, two disc springs are stacked in series, which increases the deflection of the biasing mechanism. As a result, even if the input shaft moves axially, the amount of movement can be prevented from exceeding the total deflection of the disc springs, thereby reducing wear on the parts that come into contact with the disc springs.

[0009] The power transmission device according to the second aspect is the power transmission device according to the first aspect, and is configured as follows: The inner diameter of the first disc spring is smaller than the inner diameter of the second disc spring, and the inner peripheral end of the second disc spring abuts against the first disc spring.

[0010] A power transmission device according to a third aspect is the power transmission device according to the second aspect, and is configured as follows: The second rotating member has an engaged portion. The first disc spring and the second disc spring have slits. Each slit extends radially outward from the inner circumferential end. The friction member has a friction portion and a claw portion. The friction portion contacts the first rotating member. The claw portion extends from the friction portion toward the second rotating member. The claw portion engages with the engaged portion. The claw portion engages with each slit.

[0011] A power transmission device according to a fourth aspect is the power transmission device according to the third aspect, and is configured as follows: The first disc spring has an inner peripheral end that is disposed radially inward relative to the claw portion.

[0012] A power transmission device according to a fifth aspect is the power transmission device according to the fourth aspect, and is configured as follows: The second disc spring has an inner circumferential end that is arranged to overlap with the claw portion when viewed in the circumferential direction.

[0013] A power transmission device according to a sixth aspect is the power transmission device according to any one of the third to fifth aspects, and is configured as follows: The first disc spring has a plurality of slits. The second disc spring has a plurality of slits. Each slit of the first disc spring overlaps with each slit of the second disc spring when viewed in the axial direction.

[0014] A power transmission device according to a seventh aspect is the power transmission device according to any one of the third to sixth aspects, and is configured as follows: The slits of the first disc spring have the same width as the slits of the second disc spring.

[0015] A power transmission device according to an eighth aspect is the power transmission device according to any one of the first to seventh aspects, and is configured as follows: The first disc spring has a thickness greater than the thickness of the second disc spring. [Effects of the Invention]

[0016] According to the present invention, wear of the portion that comes into contact with the disc spring can be suppressed. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. [Figure 2] Cross section of line AA in Figure 1. [Figure 3] FIG. [Figure 4] Front view of the first disc spring. [Figure 5] Front view of the second disc spring. [Figure 6] FIG. 10 is a cross-sectional view of a biasing mechanism according to a modified example. [Figure 7] FIG. 10 is a cross-sectional view of a biasing mechanism according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0018] A damper device 100 (an example of a power transmission device) according to this embodiment will be described below with reference to the drawings. In the following description, the axial direction refers to the direction in which the rotation axis O of the damper device 100 extends. The circumferential direction refers to the circumferential direction of a circle centered on the rotation axis O, and the radial direction refers to the radial direction of a circle centered on the rotation axis O.

[0019] FIG. 1 is a front view of the damper device 100, and FIG. 2 is a cross-sectional view taken along line AA in FIG. 1. As shown in FIGS. 1 and 2, the damper device 100 is provided between an internal combustion engine (not shown) and an output device (not shown). The output device is, for example, a transmission or an electric motor. The damper device 100 is attached to a flywheel (not shown). The damper device 100 may be attached to the flywheel via a torque limiter. In FIG. 2, the internal combustion engine is disposed on the left side of the damper device 100, and the output device is disposed on the right side of the damper device 100. The damper device 100 is configured to damp torque fluctuations between the internal combustion engine and the output device.

[0020] The damper device 100 includes an output rotary member 2 (an example of a first rotary member), an input rotary member 3 (an example of a second rotary member), a plurality of elastic members 4, a friction member 5, and a biasing mechanism 6.

[0021] <Output rotating member> The output rotary member 2 is configured to transmit torque from the input rotary member 3 to an output side device. The output rotary member 2 is disposed rotatably about a rotation axis O.

[0022] The output rotary member 2 has a flange plate 21 and a hub 22. The flange plate 21 and the hub 22 are configured to rotate integrally.

[0023] The flange plate 21 has an opening 211 in the center. That is, the flange plate 21 is annular. The flange plate 21 also has a plurality of accommodating holes 212. The accommodating holes 212 are arranged at intervals in the circumferential direction. Each accommodating hole 212 is configured to accommodate an elastic member 4.

[0024] The hub 22 is cylindrical. The hub 22 extends in the axial direction. The hub 22 passes through openings of a first plate 31 and a second plate 32 (described later) in the axial direction. The hub 22 has a spline hole 221 extending in the axial direction. An input shaft (not shown) of a transmission is spline-fitted into this spline hole 221. The input shaft extends from the hub 22 to the first side in the axial direction.

[0025] The hub 22 is press-fitted into the opening 211 of the flange plate 21. Therefore, the hub 22 rotates integrally with the flange plate 21. Note that the hub 22 may be formed integrally with the flange plate 21 by a single member.

[0026] <Input rotating member> The input rotary member 3 is arranged to be rotatable relative to the output rotary member 2. The input rotary member 3 has a first plate 31 and a second plate 32. The first plate 31 and the second plate 32 are both annular members having an opening in their centers. The hub 22 of the output rotary member 2 extends through the openings of the first plate 31 and the second plate 32.

[0027] The first plate 31 and the second plate 32 rotate integrally with each other. The first plate 31 and the second plate 32 are immovable relative to each other in the axial direction. Specifically, the first plate 31 and the second plate 32 are fixed to each other by a plurality of rivets 34.

[0028] The first plate 31 and the second plate 32 are arranged at an interval in the axial direction. The flange plate 21 is arranged between the first plate 31 and the second plate 32 in the axial direction. The first plate 31 and the second plate 32 are arranged to be rotatable relative to the flange plate 21.

[0029] The first plate 31 is disposed on a first axial side relative to the flange plate 21. The first plate 31 is disposed axially apart from the flange plate 21. The second plate 32 is disposed axially on a second axial side relative to the flange plate 21. The second plate 32 is disposed axially apart from the flange plate 21.

[0030] The first plate 31 and the second plate 32 each have a plurality of window portions 311, 321. The window portions 311, 321 are arranged at intervals from each other in the circumferential direction. Each window portion 311, 321 is configured to accommodate an elastic member 4. Each window portion 311, 321 is arranged at a position overlapping with each accommodation hole 212 when viewed in the axial direction.

[0031] The input rotary member 3 has a plurality of engaged portions 33. More specifically, the first plate 31 has a plurality of engaged portions 33. Each engaged portion 33 penetrates the first plate 31 in the axial direction. That is, each engaged portion 33 is a through hole. Each engaged portion 33 is arranged at intervals from one another in the circumferential direction. Each engaged portion 33 is formed on the inner peripheral end portion of the first plate 31.

[0032] <Elastic material> The elastic member 4 is configured to elastically connect the input rotary member 3 and the output rotary member 2 in the rotational direction. That is, the elastic member 4 elastically connects the flange plate 21 and the first and second plates 31, 32 in the rotational direction. The elastic member 4 is, for example, a coil spring.

[0033] The elastic member 4 is housed in the housing hole 212 of the flange plate 21. The elastic member 4 is housed in the window portion 311 of the first plate 31 and also in the window portion 321 of the second plate 32.

[0034] <Friction materials> 3 is an enlarged cross-sectional view of the damper device 100. As shown in FIGS. 1 to 3, the friction member 5 is disposed axially between the output rotary member 2 and the input rotary member 3. More specifically, the friction member 5 is disposed axially between the flange plate 21 and the first plate 31. The friction member 5 is disposed between the flange plate 21 and the first plate 31 so as to be movable in the axial direction.

[0035] The friction member 5 is annular and extends in the circumferential direction. The friction member 5 is configured to rotate integrally with the input rotation member 3. More specifically, the friction member 5 is configured to rotate integrally with the first plate 31. The friction member 5 may rotate relative to the input rotation member 3 within a predetermined range.

[0036] The friction member 5 is arranged to be rotatable relative to the output rotation member 2. More specifically, the friction member 5 is arranged to be rotatable relative to the flange plate 21. The friction member 5 rotates relative to the flange plate 21 while in contact with the flange plate 21, thereby generating a friction force.

[0037] The friction member 5 has a friction portion 51 and a plurality of claw portions 52. The friction portion 51 is in axial contact with the output rotation member 2. More specifically, the friction portion 51 is in contact with the flange plate 21. The friction portion 51 has an annular shape extending in the circumferential direction. The friction portion 51 has a friction material 511 attached to the surface facing the flange plate 21. Note that the friction portion 51 does not necessarily have to have the friction material 511.

[0038] The claw portions 52 are arranged at intervals from one another in the circumferential direction. Each claw portion 52 extends in the axial direction from the friction portion 51. Each claw portion 52 extends from the friction portion 51 toward the input rotation member 3. More specifically, each claw portion 52 extends toward the first plate 31. That is, each claw portion 52 extends toward a first side in the axial direction. Each claw portion 52 engages with a corresponding engaged portion 33 so as to rotate integrally with the input rotation member 3.

[0039] <Biasing mechanism> The biasing mechanism 6 biases the friction member 5 in the axial direction toward the output rotation member 2. More specifically, the biasing mechanism 6 biases the friction member 5 toward the flange plate 21. As a result, when the friction member 5 rotates relative to the flange plate 21, a frictional force is generated.

[0040] The biasing mechanism 6 has a first disc spring 61 and a second disc spring 62. The first disc spring 61 and the second disc spring 62 are stacked in series. Specifically, the first disc spring 61 and the second disc spring 62 are stacked such that their outer peripheral ends are spaced apart and their inner peripheral ends are close to each other. More specifically, the outer peripheral end of the first disc spring 61 is disposed on a second axial side relative to the inner peripheral end. Meanwhile, the outer peripheral end of the second disc spring 62 is disposed on a first axial side relative to the inner peripheral end.

[0041] The inner diameter of the first disc spring 61 is smaller than the inner diameter of the second disc spring 62. That is, the inner peripheral end of the first disc spring 61 is disposed radially inward relative to the inner peripheral end of the second disc spring 62. The inner peripheral end of the second disc spring 62 abuts against the first disc spring 61. As a result, the second disc spring 62 is positioned radially relative to the first disc spring 61.

[0042] FIG. 4 is a front view of the first disc spring 61. Note that FIG. 4 also shows the claw portions 52. As shown in FIG. 4, the first disc spring 61 has a plurality of slits 611. The slits 611 are arranged at intervals from one another in the circumferential direction. Each slit 611 extends radially outward from the inner circumferential end of the first disc spring 61. That is, each slit 611 opens radially inward. Each claw portion 52 engages with each slit 611. Therefore, the first disc spring 61 rotates integrally with the friction member 5. Note that the number of slits 611 is greater than the number of claw portions 52, and therefore the claw portions 52 are not engaged with some of the slits 611.

[0043] FIG. 5 is a front view of the second disc spring 62. Note that FIG. 5 also shows the claw portions 52. As shown in FIG. 5, the second disc spring 62 has a plurality of slits 621. The slits 621 are arranged at intervals in the circumferential direction. Each slit 621 extends radially outward from the inner circumferential end of the second disc spring 62. That is, each slit 621 opens radially inward. Each claw portion 52 engages with each slit 621. Therefore, the second disc spring 62 rotates integrally with the friction member 5. Note that the number of slits 621 is greater than the number of claw portions 52, and therefore the claw portions 52 are not engaged with some of the slits 621.

[0044] 4 and 5, the inner peripheral end of the first disc spring 61 is disposed radially inward from the claw portion 52. On the other hand, the inner peripheral end of the second disc spring 62 is not disposed radially inward from the claw portion 52. Specifically, the inner peripheral end of the second disc spring 62 is disposed so as to overlap with the claw portion 52 when viewed in the circumferential direction.

[0045] Each slit 611 of the first disc spring 61 has the same width as each slit 621 of the second disc spring 62. The width of each slit 611, 621 refers to the dimension of each slit 611, 621 in the circumferential direction. Each slit 611 of the first disc spring 61 overlaps with each slit 621 of the second disc spring 62 when viewed in the axial direction. In other words, the circumferential position where each slit 611 is formed in the first disc spring 61 is the same as the circumferential position where each slit 621 is formed in the second disc spring 62.

[0046] As shown in FIG. 3 , the outer peripheral end of the first disc spring 61 is in contact with the friction member 5. More specifically, the outer peripheral end of the first disc spring 61 is in contact with the friction portion 51 of the friction member 5. The outer peripheral end of the second disc spring 62 is in contact with the input rotation member 3. More specifically, the outer peripheral end of the second disc spring 62 is in contact with the first plate 31 of the input rotation member 3.

[0047] In this way, because the biasing mechanism 6 is composed of the first disc spring 61 and the second disc spring 62 stacked in series, the amount of deflection can be made larger than in a biasing mechanism composed of a single disc spring. Therefore, even if the input shaft moves in the axial direction, the amount of movement can be prevented from exceeding the amount of deflection of the biasing mechanism 6. As a result, wear of the friction portion 51 that contacts the outer peripheral end of the first disc spring 61 and wear of the first plate 31 that contacts the outer peripheral end of the second disc spring 62 can be prevented.

[0048] [Variations] Although the embodiments of the present invention have been described above, the present invention is not limited to these, and various modifications are possible without departing from the spirit of the present invention. Note that the following modifications can basically be applied simultaneously.

[0049] (a) In the above embodiment, the biasing mechanism 6 biases the friction member 5 toward the output rotary member 2, but the configuration of the damper device 100 is not limited to this. For example, the biasing mechanism 6 may bias the friction member 5 toward the input rotary member 3. In other words, the biasing mechanism 6 may bias the friction member 5 toward the first plate 31. In this case, the positions of the biasing mechanism 6 and the friction member 5 may be interchanged.

[0050] (b) The friction member 5 may rotate integrally with the output rotational member 2 and frictionally engage with the input rotational member 3. For example, the flange plate 21 of the output rotational member 2 has an engaged portion 33. The friction portion 51 of the friction member 5 contacts the input rotational member 3, and the claw portion 52 extends toward the flange plate 21 and engages with the engaged portion 33. In this case, the output rotational member 2 is an example of a second rotational member, and the input rotational member 3 is an example of a first rotational member.

[0051] (c) In the above embodiment, the friction member 5 and the biasing mechanism 6 were disposed between the first plate 31 and the flange plate 21, but the friction member 5 and the biasing mechanism 6 may also be disposed between the second plate 32 and the flange plate 21.

[0052] 6, the inner diameter of the first disc spring 61 may be the same as the inner diameter of the second disc spring 62. In this case, it is preferable to dispose an intermediate member 63 between the first disc spring 61 and the second disc spring 62.

[0053] (e) In the above embodiment, the plate thickness of the first disc spring 61 and the plate thickness of the second disc spring 62 are the same, but these plate thicknesses may be different from each other. For example, as shown in Figure 7, the plate thickness of the first disc spring 61 can be made thicker than the plate thickness of the second disc spring 62.

[0054] (f) In the above embodiment, the biasing mechanism 6 is composed of two disc springs, the first disc spring 61 and the second disc spring 62, but it may be composed of three or more disc springs. In this case, the third disc spring may be stacked in parallel with the first disc spring 61 or the second disc spring 62, or may be stacked in series with the first disc spring 61 or the second disc spring 62. [Explanation of symbols]

[0055] 2: Output rotating member 3: Input rotating member 33: Engaged part 5: Friction material 51:Friction part 52: Claw part 6: Biasing mechanism 61: First disc spring 611: Slit 62: Second disc spring 621: Slit 100: Damper device

Claims

1. a first rotating member; a second rotating member arranged to be rotatable relative to the first rotating member; a friction member disposed between the first rotary member and the second rotary member in the axial direction; a biasing mechanism that biases the friction member toward the first rotary member or the second rotary member; Equipped with The biasing mechanism includes a first disc spring and a second disc spring stacked in series on the first disc spring. Power transmission device.

2. an inner diameter of the first disc spring is smaller than an inner diameter of the second disc spring; an inner peripheral end of the second disc spring abuts against the first disc spring; The power transmission device according to claim 1 .

3. the second rotating member has an engaged portion, the first disc spring and the second disc spring have slits extending radially outward from their inner circumferential ends, the friction member has a friction portion that contacts the first rotating member and a claw portion that extends from the friction portion toward the second rotating member and engages with the engaged portion, The claw portions engage with the respective slits. The power transmission device according to claim 2 .

4. The first disc spring has an inner circumferential end disposed radially inward with respect to the claw portion. The power transmission device according to claim 3 .

5. the second disc spring has an inner circumferential end that is arranged to overlap the claw portion when viewed in the circumferential direction; 5. The power transmission device according to claim 4.

6. the first disc spring has a plurality of the slits, the second disc spring has a plurality of the slits, Each slit of the first disc spring overlaps with each slit of the second disc spring when viewed in the axial direction. The power transmission device according to claim 3 .

7. The slit of the first disc spring has the same width as the slit of the second disc spring. The power transmission device according to claim 3 .

8. The first disc spring has a thickness greater than a thickness of the second disc spring. The power transmission device according to claim 1 .

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