Damping device

Abstract

In a vibration damping device, generation of abnormal noise in a pre-damper unit is suppressed. The vibration damping device (1) is provided with a pre-damper (50). The pre-damper (50) elastically links a hub (30) and a flange (40) in a rotational direction and operates in a low torsion angle region. The pre-damper (50) has first and second small coil springs (53, 54). The first small coil spring (53) is arranged in a compressed state at a neutral time when the hub (30) and the flange (40) do not rotate relative to each other and exerts a force on the flange (40) to a first side in the rotational direction relative to the hub (30). The second small coil spring (54) is arranged in a compressed state at the neutral time and exerts a force on the flange (40) to a second side in the rotational direction relative to the hub (30).

Description

Technical Field

[0001] This invention relates to a vibration damping device. Background Technology

[0002] In order to transmit the power generated by the engine to the transmission side and to dampen rotational fluctuations, the vehicle is equipped with a damping device.

[0003] This vibration damping device has an input rotating body, an output rotating body, and multiple helical springs. The helical springs are arranged in the window of the input rotating body and the window of the output rotating body, elastically connecting the input rotating body and the output rotating body in the rotational direction.

[0004] In addition, in vibration damping devices, especially in order to suppress vibration and abnormal noise at idle speed, a pre-damping unit is sometimes provided in addition to the main vibration damping unit (for example, Patent Document 1).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2019-90428

[0008] In the pre-damping unit shown in Patent Document 1, the output-side rotating body consists of a cylindrical hub, a circular flange disposed on the outer periphery of the hub, and multiple springs disposed between them. Multiple teeth are formed on the outer periphery of the hub, and these teeth engage with multiple recesses formed on the inner periphery of the flange. Furthermore, a circumferential gap is formed between these teeth and the recesses, allowing the hub and flange to rotate relative to each other by the angle of this gap.

[0009] In such a pre-damping unit, there are problems such as loosening in the rotational direction due to the relationship between the gap between the hub and the flange and the length of the spring, which in turn causes abnormal noise. Summary of the Invention

[0010] The technical problem of the present invention is to suppress the generation of abnormal noise in the pre-damping unit in the vibration damping device.

[0011] (1) The vibration damping device of the present invention comprises a first rotating body, a second rotating body, a first pre-damper, and a first main elastic member. The second rotating body has a cylindrical hub and a flange disposed on the outer periphery of the hub in a manner rotatable relative to the hub, and the second rotating body is rotatable relative to the first rotating body. The first pre-damper elastically connects the hub and the flange in the rotational direction and operates within a first torsion angle region of the first rotating body and the second rotating body. The first main elastic member is disposed at a position different from the first pre-damper in the circumferential direction and elastically connects the first rotating body and the second rotating body in the rotational direction, and the first main elastic member operates within a second torsion angle region larger than the first torsion angle region.

[0012] Furthermore, the first pre-damper has a first elastic element and a second elastic element. The first elastic element is configured in a compressed state when the hub and flange are neutral and not rotating relative to each other, applying force to the flange on a first side relative to the hub in the direction of rotation. The second elastic element is configured in a compressed state when neutral, applying force to the flange on a second side relative to the hub in the direction of rotation.

[0013] In this device, the first pre-damper operates in a first torsion angle region where the torsion angle between the first and second rotating bodies is small, such as at idle speed. Conversely, the first main elastic member operates in a second torsion angle region where the torsion angle between the first and second rotating bodies is large.

[0014] Here, the first and second elastic components of the first pre-damper are compressed between the hub and the flange, and each elastic component applies force to the flange in a different direction relative to the hub. Therefore, in neutral conditions, the gap between the hub and the flange is maintained at a certain gap by the two elastic components, for example, at idle speed, which can suppress abnormal noise caused by the collision between the hub and the flange.

[0015] (2) Preferably, when the hub rotates relative to the flange on a first side in the rotational direction, the first elastic member is further compressed. In this case, when the hub rotates relative to the flange on a second side in the rotational direction, the second elastic member is further compressed.

[0016] (3) Preferably, the first elastic member extends when the hub rotates to the second side in the rotational direction relative to the flange. In addition, the second elastic member extends when the hub rotates to the first side in the rotational direction relative to the flange.

[0017] (4) Preferably, the hub has a plurality of first engaging portions and a support portion on its outer circumferential surface. In this case, the flange has a plurality of second engaging portions and a retaining slit on its inner circumferential surface. The plurality of second engaging portions are spaced apart in the circumferential direction and are opposite to the plurality of first engaging portions. The retaining slit has a predetermined width and is into which the support portion is inserted.

[0018] Furthermore, a first elastic member is installed in a compressed state between one end of the support portion and one end of the retaining notch. Additionally, a second elastic member is installed in a compressed state between the other end of the support portion and the retaining notch.

[0019] (5) Preferably, the flange has a first window for receiving the first main elastic component. Additionally, preferably, the damping device also includes a stop mechanism that limits the relative rotation angle between the first rotating body and the second rotating body within a predetermined angle range.

[0020] The stopping mechanism has a first cut and a second cut formed on the flange, and two stopping members fixed to the first rotating body. The first cut is formed by extending circumferentially on one side of the first window opening. The second cut is a hole formed by extending circumferentially on the other side of the first window opening, and its end near the first window opening communicates with the first window opening. The two stopping members are movable circumferentially within the first cut and the second cut.

[0021] In this vibration damping device, one end of the second cut is connected to the first window opening. Therefore, the circumferential length of the second cut can be increased. That is, the range of motion of the stop mechanism can be expanded, and the relative rotation angle (torsion angle) between the first rotating body and the second rotating body in one direction can be widened.

[0022] (6) Preferably, the first cut is provided separately from the first window opening. In this case, since the first cut is provided separately from the first window opening, the reduction in the strength of the flange can be suppressed compared to the case where the first cut and the first window opening are connected.

[0023] (7) Preferably, the first cut is formed in an arc shape on the first pitch radius. In this case, the second cut is a hole formed in an arc shape on a second pitch radius that is closer to the inner circumference than the first pitch radius.

[0024] Here, by changing the pitch radius of the first cut and the pitch radius of the second cut, the first cut and the second cut, separated by the first window hole, can be brought closer to each other. That is, the angle formed by adjacent cuts and the rotation axis can be made close to 90°, and the unevenness of the strength of the first rotating body and the flange can be suppressed.

[0025] (8) Preferably, the first window opening has a protrusion on one of its circumferential pressing surfaces, the protrusion bulging outward in the circumferential direction at the radial center of the pressing surface. In this case, the end of the first cut near the first window opening extends toward the protrusion.

[0026] Here, one end of the first cut can be extended to the extent that it is embedded in the protrusion of the first window hole. Therefore, the circumferential length of the first cut can be increased.

[0027] (9) Preferably, the damping device further comprises a second primary elastic member. The second primary elastic member is disposed radially outside the first pre-damper and elastically connects the first rotating body and the second rotating body in the rotational direction. In this case, the first rotating body has a pair of windows that are longer than the circumferential length of the second primary elastic member, and the flange has a pair of window openings that receive the second primary elastic member.

[0028] (10) Preferably, the vibration damping device further comprises a second pre-damper, a third main elastic component, and a fourth main elastic component. The second pre-damper is disposed opposite to the first pre-damper across the rotation axis of the first rotating body, and together with the first pre-damper, elastically connects the hub and the flange in the rotational direction. The third main elastic component is disposed opposite to the first main elastic component across the rotation axis of the first rotating body, and together with the first main elastic component, elastically connects the first rotating body and the second rotating body in the rotational direction. The fourth main elastic component is disposed opposite to the second main elastic component across the rotation axis of the first rotating body and radially outside the second pre-damper, and together with the second main elastic component, elastically connects the first rotating body and the second rotating body in the rotational direction.

[0029] Invention Effects

[0030] In the present invention as described above, in a vibration damping device having a pre-damping unit, the generation of abnormal noise in the pre-damping unit can be suppressed. Attached Figure Description

[0031] Figure 1 This is a cross-sectional view of a vibration damping device with a torque limiter according to one embodiment of the present invention.

[0032] Figure 2 This is the front view of the vibration damping unit.

[0033] Figure 3 This is the main view of the second panel.

[0034] Figure 4 This is the front view of the flange.

[0035] Figure 5 This is a side view of the first spring seat.

[0036] Figure 6 yes Figure 5 Sectional view along line VI-VI.

[0037] Figure 7 This is a partial front view of the pre-damper.

[0038] Figure 8yes Figure 1 A magnified partial view.

[0039] Figure 9 This is the front view of the spring retainer.

[0040] Figure 10 It is a three-dimensional view of the supporting component.

[0041] Figure 11 It is a torsion characteristic curve diagram. Detailed Implementation

[0042] [Overall Structure]

[0043] Figure 1 This is a cross-sectional view of a vibration damping device 1 with a torque limiter according to one embodiment of the present invention (hereinafter, sometimes simply referred to as "vibration damping device"). Additionally, Figure 2 This is a front view of the vibration damping device 1, showing it with some components disassembled or partially removed. Figure 1 In the diagram, the OO line is the axis of rotation. Figure 1 In the middle, an engine is arranged on the left side of the vibration damping device 1, and a drive unit including an electric motor and a transmission device is arranged on the right side.

[0044] It should be noted that in the following description, axial direction refers to the direction in which the rotation axis O of the vibration damping device 1 extends. Additionally, circumferential direction refers to the circumferential direction of the circle centered on the rotation axis O, and radial direction refers to the radial direction of the circle centered on the rotation axis O. It should be noted that the circumferential direction does not need to be exactly the same as the circumferential direction of the circle centered on the rotation axis O; for example, it may also include the direction of the circle centered on the rotation axis O. Figure 2 The upper part shows the concept of the window portion and the window opening as references to the left and right directions. Furthermore, the radial direction does not need to be perfectly aligned with the diameter direction of the circle centered on the rotation axis O; for example, it also includes the direction of... Figure 2 The upper part of the window and the concept of the vertical direction based on the window opening are shown.

[0045] The vibration damping device 1 is disposed between a flywheel (not shown) and the input shaft of the drive unit, and is used to limit the torque transmitted between the engine and the drive unit and to attenuate rotational fluctuations. The vibration damping device 1 includes a torque limiter unit 10 and a vibration damping unit 20.

[0046] [Torque Limiter Unit 10]

[0047] The torque limiter unit 10 is disposed on the outer periphery of the damping unit 20. The torque limiter unit 10 limits the torque transmitted between the flywheel and the damping unit 20. The torque limiter unit 10 has a first side plate 11 and a second side plate 12, a friction disc 13, a pressure plate 14, and a conical spring 15.

[0048] The first side plate 11 and the second side plate 12 are fixed to each other by a plurality of rivets. The friction disc 13 has a core plate 131 and a pair of friction components 132. A pressure plate 14 and a conical spring 15 are disposed between the first side plate 11 and the friction disc 13. The conical spring 15 presses the friction disc 13 toward the second side plate 12 via the pressure plate 14.

[0049] [Vibration Damping Unit 20]

[0050] The vibration damping unit 20 consists of an input side plate 21 (an example of a first rotating body), a hub flange 22 (an example of a second rotating body), and a vibration damping part 23 disposed between the input side plate 21 and the hub flange 22.

[0051] <Input Side Panel 21>

[0052] The input side panel 21 has a first plate 211 and a second plate 212 (hereinafter, the first plate 211 and the second plate 212 are sometimes referred to together as "input side panel 21"). For example... Figure 3 As shown, both the first plate 211 and the second plate 212 are annular components with a central hole. It should be noted that... Figure 3 Only the second plate 212 is shown, but the first plate 211 is the same in terms of basic structure. The first plate 211 and the second plate 212 are connected by four stop pins 24 (see reference). Figure 2 They are fixed to each other by a predetermined interval in the axial direction. Therefore, the first plate 211 and the second plate 212 cannot move relative to each other in the axial and rotational directions. Additionally, as... Figure 1 As shown, the inner periphery of the core plate 131 of the friction disc 13 is fixed to the outer periphery of the second plate 212 by four rivets 25.

[0053] like Figure 3 As shown, a pair of first windows 21a and a pair of second windows 21b are formed on the first plate 211 and the second plate 212, respectively. The pair of first windows 21a are arranged opposite each other with a rotation axis O between them. Figure 3 The diagram shows the first window portion 21a and the second window portion 21b of the second plate 212, but the first window portion and the second window portion of the first plate 211 have the same structure. The pair of first window portions 21a are formed by cutting the plates 211 and 212 respectively, and have pressing surfaces 21c on both end faces in the circumferential direction, and support portions on the outer and inner peripheries respectively. Furthermore, the pair of second window portions 21b are arranged opposite the first window portions 21a at a 90° interval, separated by a rotation axis O. The pair of second window portions 21b are arc-shaped openings extending in the circumferential direction and penetrating in the axial direction, and have pressing surfaces 21d on both end faces in the circumferential direction.

[0054] In addition, on the first plate 211 and the second plate 212, four assembly holes 21e for riveting rivets 25 are formed at positions corresponding to the rivets 25.

[0055] <Hub flange 22>

[0056] The hub flange 22 is a component used to transmit torque from the input side plate 21 to the output side. For example... Figure 1 as well as Figure 2 As shown, hub flange 22 has hub 30 and flange 40.

[0057] The hub 30 is a cylindrical component disposed within the central holes of the first plate 211 and the second plate 212. A spline hole is formed on the inner circumference of the hub 30, allowing the output-side component to engage with the spline hole. Additionally, eight teeth 30a (an example of the first engaging portion) and a pair of protrusions 30b (an example of the support portion) are formed on the outer circumferential surface of the hub 30. The pair of protrusions 30b are arranged opposite each other across the rotation shaft O.

[0058] like Figure 2 as well as Figure 4 As shown, the flange 40 is formed in the shape of a circular plate and is disposed between the first plate 211 and the second plate 212 in the axial direction. The flange 40 has a pair of first window holes 41a and a pair of second window holes 41b, as well as a pair of first stop holes 42a (an example of a first cut) and a pair of second stop holes 42b (an example of a second cut). In addition, the flange 40 has an opening 43 formed at its center for the hub 30 to be inserted. Eight engaging holes 43a (an example of a second engaging portion) and a pair of retaining cuts 43b are formed on the inner circumferential surface of the opening 43. It should be noted that four of the eight engaging holes 43a communicate with the pair of retaining cuts 43b, and the shape of the engaging holes is not explicitly defined.

[0059] The first window opening 41a is disposed opposite to the first window portion 21a of the first plate 211 and the second plate 212 across the rotation axis O. The first window opening 41a has pressing surfaces 41c on both end faces in the circumferential direction. In addition, the pressing surface 41c on the R1 side (hereinafter referred to as "R1 side") of the first window opening 41a in the circumferential direction has a protrusion 41d, which protrudes in a manner that bulges toward the opposing pressing surface 41c (i.e., in the circumferential direction).

[0060] The second window 41b is positioned opposite the first window 41a at a 90° interval across the rotation axis O. That is, the second window 41b is formed at a position corresponding to the second window portion 21b of the first plate 211 and the second plate 212. The second window 41b is rectangular, and its radial position (the center of the radial width of the hole) is located closer to the radial inward side than the radial center of the first window 41a. The second window 41b has pressing surfaces 41f on its two end faces in the circumferential direction, and the distance between the two pressing surfaces 41f is set to be shorter than the distance (circumferential length) between the two pressing surfaces 21d of the second window portion 21b of the input side plate 21.

[0061] like Figure 4 As shown, the first stop hole 42a is an elongated hole extending in an arc shape on the R1 side of the first window hole 41a. The first stop hole 42a is formed separately from the first window hole 41a. The end of the first stop hole 42a on the side away from the first window hole 41a extends to the radially outer side of the second window hole 41b. In addition, the end of the first stop hole 42a on the side near the first window hole 41a extends toward the protrusion 41d of the first window hole 41a. Specifically, the end of the first stop hole 42a on the first window hole 41a side reaches the straight line L. Here, the straight line L is a straight line connecting the outer peripheral end face and the inner peripheral end face of the first window hole 41a where the protrusion 41d is not formed.

[0062] The second stop hole 42b is an elongated hole extending in an arc shape on the R2 side (hereinafter referred to as "R side") in the circumferential direction of the first window hole 41a. The end of the second stop hole 42b on the R1 side is connected to the radial center of the first window hole 41a.

[0063] Furthermore, in both the first stop hole 42a and the second stop hole 42b, a bulge 42c is formed near the end on the R2 side. This bulge 42c is formed at the same size as the assembly hole 21e of the rivet 25 in the input side plate 21. The rivet 25 can be riveted through this bulge 42c and the assembly hole 21e.

[0064] In this structure, compared to the case where no protrusion 41d is formed in the first window hole 41a, the end of the first stop hole 42a on the first window hole 41a side can be further extended. Furthermore, since one end of the second stop hole 42b communicates with the first window hole 41a, the circumferential length of the second stop hole 42b can be made longer. As a result, the angle formed between the pair of stop pins 24 across the first window hole 41a and the rotation axis O can approach 90°.

[0065] Furthermore, the stop pin 24 passes axially through the first stop hole 42a and the second stop hole 42b. Therefore, the input side plate 21 and the hub flange 22 can rotate relative to each other within the range that the stop pin 24 can move within each stop hole 42a, 42b. In other words, the stop mechanism 45 is formed by the stop pin 24 and each stop hole 42a, 42b, and the relative rotation of the input side plate 21 and the hub flange 22 is restricted by the stop pin 24 abutting against the end faces of each stop hole 42a, 42b.

[0066] Here, the pair of first window holes 41a are in the same radial position, but the pitch radius P1 (radius of the radial center of the first stop hole 42a) of the first stop hole 42a is greater than the pitch radius P2 of the second stop hole 42b. That is, the first stop hole 42a and the second stop hole 42b are formed at radially offset positions.

[0067] Therefore, the R2-side end of the first stop hole 42a can extend toward the radial center portion (i.e., the protrusion 41d) of the first window hole 41a. Furthermore, the R1-side end of the second stop hole 42b can communicate with the radial center portion of the first window hole 41a.

[0068] Four of the eight engaging holes 43a are formed at positions opposite to the two engaging holes 43a, separated by the rotation axis O. For example... Figure 2 As shown, in the four engagement holes 43a, four of the eight teeth 30a of the hub 30 are engaged on both sides of the circumferential direction with a specified gap (corresponding to the angle θ1).

[0069] A pair of retaining slits 43b are formed at a position offset from a pair of first window openings 41a by 90° (i.e., at the same position as a pair of second window openings 41b in the circumferential direction). The retaining slits 43b are formed in a straight line in the circumferential direction and have a predetermined width. That is, one end of the retaining slit 43b extends toward one side of the pair of first window openings 41a, and the other end extends toward the other side of the pair of first window openings 41a.

[0070] <Vibration Damping Section 23>

[0071] like Figure 1 as well as Figure 2 As shown, the damping unit 23 has a pair of large helical springs 47 (an example of the first and second main elastic components), a pair of resin components 48 (an example of the third and fourth main elastic components), a pair of pre-dampers 50 (an example of the first and second pre-dampers), and a hysteresis generating mechanism 60.

[0072] A pair of large helical springs 47 and a pair of resin components 48 are mechanisms for elastically connecting the input side plate 21 and the hub flange 22 in the direction of rotation.

[0073] -Large helical spring 47 and resin component 48-

[0074] The large helical spring 47 is housed in the first window 41a of the flange 40, and the resin component 48 is housed in the second window 41b of the flange 40. In addition, the large helical spring 47 and the resin component 48 are supported axially and radially by the windows 21a and 21b of the first plate 211 and the second plate 212, respectively.

[0075] It should be noted that, as Figure 2 As shown, the resin component 48 is disposed with a gap (equivalent to angle θ2) in the circumferential direction relative to the second window portion 21b of the input side plate 21. On the other hand, the resin component 48 is disposed without gap in the circumferential direction relative to the second window hole 41b of the flange 40.

[0076] A first spring seat 71 is provided on the end face of the large helical spring 47 on the R1 side. For example... Figure 5 as well as Figure 6 As shown, the first spring seat 71 has an end face support portion 711 and an outer peripheral support portion 712. It should be noted that... Figure 5 This is a side view of the first spring seat 71 (viewed from one side in the circumferential direction). Figure 6 yes Figure 5 Sectional view along line VI-VI.

[0077] The end face support 711 supports the R1 side end face of the large helical spring 47, and is supported on the pressing surface 21c of the first window portion 21a of the input side plate 21 and the pressing surface 41c of the first window hole 41a of the flange 40. In the end face support 711, as... Figure 6 As shown, a recess 711a, which is arc-shaped and recessed toward the large helical spring 47, is formed on the pressing surface 41c supported by the first window hole 41a. Furthermore, a hole 711b, which extends in the circumferential direction, is provided at the central portion of this recess 711a, both radially and axially. Additionally, the protrusion 41d of the first window hole 41a of the flange 40 is inserted into this recess 711a.

[0078] The outer peripheral support portion 712 is formed to extend circumferentially from the outer peripheral end of the end face support portion 711. This outer peripheral support portion 712 is disposed between the outer peripheral portion of the R1 side end of the large helical spring 47 and the inner peripheral surfaces of the first window portion 21a and the first window hole 41a. Therefore, even if the large helical spring 47 moves outward under centrifugal force or in a compressed state, contact between the large helical spring 47 and the first window portion 21a and the first window hole 41a can be avoided.

[0079] Furthermore, a second spring seat 72 is provided on the R2 side end face of the large helical spring 47. More specifically, the R2 side end face of the large helical spring 47 is supported by the second spring seat 72, which is supported by the pressing surface 21c on the R2 side of the first window portion 21a and the pressing surface 41c on the R2 side of the first window hole 41a. This second spring seat 72 is conventionally known, and detailed description is omitted here.

[0080] -Pre-damper 50-

[0081] A pair of pre-dampers 50 are a mechanism for elastically connecting the hub 30 and the flange 40 in the rotational direction. For example... Figure 2 As shown, a pair of pre-dampers 50 are arranged opposite each other across the rotation axis O. Each pre-damper 50 is configured to be held radially inside the second window 41b by a pair of first window 41a. Figure 7 As shown, each pre-damper 50 has a spring retainer 51, a load-bearing member 52, and first and second small coil springs 53 and 54 (an example of the first and second elastic members).

[0082] If Figure 1 A portion of the enlarged representation Figure 8 As shown, the spring retainer 51 is disposed axially between the first plate 211 and the flange 40. Figure 9 As shown, the spring retainer 51 has a circular plate portion 511 with a hole in the center and a pair of bearing portions 512.

[0083] The inner circumferential surface of the circular plate portion 511 is supported on the outer circumferential surface of the hub 30. For example... Figure 8 As shown, on the side of the second plate 212 side of the circular plate portion 511, the teeth 30a and the protrusions 30b of the hub 30 abut against the inner periphery of the flange 40.

[0084] like Figure 9 As shown, a pair of support portions 512 are formed opposite each other on the side of the second plate 212 side of the circular plate portion 511, separated by the rotation axis O. The pair of support portions 512 have the same structure, therefore, only one support portion 512 and its related components will be described below.

[0085] The supporting portion 512 is formed protruding from the side of the circular plate portion 511 toward the side of the second plate 212. For example... Figure 7As shown, the support portion 512 extends with a predetermined width between the inner peripheral ends of a pair of first window holes 41a and is embedded in the retaining cutout 43b of the flange 40. Therefore, the flange 40 and the spring retainer 51 cannot rotate relative to each other. In addition, the support portion 512 has a pair of spring support portions 512a, 512b near the inner peripheral ends of the first window holes 41a. More specifically, the support portion 512a is located at the R1 side end and the spring support portion 512b is located at the R2 side end. Furthermore, a protrusion 30b of the hub 30 is inserted at the center of the support portion 512, that is, at the center of the opposing pair of spring support portions 512a, 512b.

[0086] like Figure 7 as well as Figure 10 As shown, the support member 52 is mounted on the protrusion 30b of the hub 30. The support member 52 is formed in a block shape, having an opening 52a that opens on the inner circumferential side and a pair of spring holes 52b and 52c that open outward on both sides. The protrusion 30b of the hub 30 is inserted into the opening 52a. The spring holes 52b and 52c have bottoms and do not extend in the circumferential direction. In addition, a first small coil spring 53 and a second small coil spring 54 are arranged in a compressed state between the support member 52 and each of the pair of support portions 512a and 512b of the spring retainer 51.

[0087] One end face of the first small coil spring 53 is supported by the bearing portion 512a on the R1 side of the spring retainer 51, and the other end face is inserted into and supported in the spring hole 52b of the bearing member 52. Similarly, one end face of the second small coil spring 54 is supported by the bearing portion 512b on the R2 side of the spring retainer 51, and the other end face is inserted into and supported in the spring hole 52c of the bearing member 52.

[0088] In this structure, the first small helical spring 53 applies force to the flange 40 in the R1 direction relative to the hub 30, and the second small helical spring 54 applies force to the flange 40 in the R2 direction relative to the hub 30.

[0089] It should be noted that the small coil springs 53 and 54 of the pre-damper 50 have lower rigidity compared to the large coil spring 47 disposed in the first window 41a. Therefore, when the damping section 23 operates, the small coil springs 53 and 54 of the pre-damper 50 operate in the region with a smaller torsional angle, while the large coil spring 47 and the resin component 48 operate in the region with a larger torsional angle after their operation stops.

[0090] In addition, such as Figure 8As shown, a cover 55 is disposed on the end face of the second plate 212 side of the spring retainer 51. That is, the cover 55 is disposed between the end face of the spring retainer 51 and the axial direction of the second plate 212. Through the cover 55, the first and second small helical springs 53 and 54 are held inside the bearing portion 512 of the spring retainer 51.

[0091] like Figure 8 As shown, the hysteresis generating mechanism 60 is disposed between the first plate 211 and the second plate 212 and the hub flange 22 in the axial direction. The hysteresis generating mechanism 60 includes a spring retainer 51 and a cover 55, and has a bushing 61 and a conical spring 62. The bushing 61 and the conical spring 62 are disposed between the cover 55 and the second plate 212 in the axial direction. The bushing 61 cannot rotate relative to the second plate 212, and the conical spring 62 is disposed in a compressed state between the bushing 61 and the second plate 212 in the axial direction.

[0092] With the above structure, if the hub 30 and the flange 40 rotate relative to each other, a relatively small first hysteresis torque is generated between the spring retainer 51 and the hub 30. Furthermore, if the first plate 211 and the second plate 212 rotate relative to the hub flange 22, a relatively large second hysteresis torque is generated between the side of the spring retainer 51 and the first plate 211, and between the cover 55 and the bushing 61.

[0093] [Assembly of torque limiter unit 10 and vibration damping unit 20]

[0094] During the assembly of the vibration damping device 1, the torque limiter unit 10 and the vibration damping unit 20 are first assembled separately. Then, the inner periphery of the core plate 131 and the outer periphery of the second plate 212 of the torque limiter unit 10 are riveted and fixed by rivets 25.

[0095] At this time, since an assembly hole 21e is formed on the first plate 211 and an assembly cutout 42c is formed on the flange 40, the riveting tool can be brought into contact with the rivet 25 and the rivet 25 can be riveted using these holes 21e and cutouts 42c.

[0096] [action]

[0097] The torque transmitted from the engine to the flywheel is input to the damping unit 20 via the torque limiter unit 10. In the damping unit 20, the torque is input to the input side plate 21 of the friction disc 13, to which the torque limiter unit 10 is fixed. This torque is then transmitted to the hub flange 22 via the pre-damper 50, the coil spring 47, and the resin component 48. Furthermore, power is transmitted from the hub flange 22 to the output side of the electric motor, generator, transmission, etc.

[0098] Additionally, for example, during engine start-up, due to the large inertia on the output side, excessive torque may sometimes be transmitted from the output side to the engine. In such cases, the torque limiter unit 10 limits the torque transmitted to the engine side to below a specified value.

[0099] <Positive and lateral torsional characteristics>

[0100] The torsional characteristics on the positive side of the damping unit 20, i.e., the characteristics when torque is input from the engine (positive torque input), will be explained.

[0101] Here, in the pre-damper 50, as described above, both the first small coil spring 53 and the second small coil spring 54 are configured in a compressed state, applying force to the flange 40 in different rotational directions relative to the hub 30. Therefore, in the neutral state where the torsion angle is "0", the circumferential clearance between the hub 30 and the flange 40 is maintained at an angle θ1, and no abnormal noise caused by loosening of either is generated.

[0102] When the positive torque is input, Figure 2 In the middle, the input side plate 21 rotates in the R1 direction. As mentioned above, the stiffness of the large helical spring 47 is higher than that of the first and second small helical springs 53 and 54. Therefore, when the torsion angle is less than the angle θ1, the large helical spring 47 does not move (is not compressed), and the input side plate 21 rotates integrally with the flange 40.

[0103] In this case, the flange 40 rotates relative to the hub 30 towards the R1 side, the second small coil spring 54 of the pre-damper 50 is further compressed, and the first small coil spring 53 extends. Therefore, as Figure 11 As shown, a low-stiffness torsional characteristic C1 can be obtained before the torsion angle becomes angle θ1. It should be noted that although the first small helical spring 53 is stretched, it is still in a compressed state at the torsion angle θ1 and will not stretch to a free state. In addition, since the hub 30 and the flange 40 rotate relative to each other, a relatively small first hysteresis torque is generated here.

[0104] When the torsion angle becomes angle θ1, the tooth 30a of the hub 30 abuts against the end face of the engagement hole 43a of the flange 40. Therefore, the hub 30 and flange 40 rotate as a unit, and the action of the two small helical springs 53 and 54 stops. In this case, the two large helical springs 47 are compressed between the second spring seat 72 supported by the pressing surface 21c on the R2 side of the first window portion 21a of the input side plate 21 and the first spring seat 71 supported by the pressing surface 41c on the R1 side of the first window hole 41a of the flange 40.

[0105] It should be noted that, as Figure 2As shown, the resin component 48 is supported without gap in the second window 41b of the flange 40 when neutral. However, in the second window portion 21b of the input side plate 21, there are circumferential gaps of θ2 on both the R1 and R2 sides. Furthermore, there are circumferential gaps of θ3 between the stop pin 24 and each stop hole 42a on both the R1 and R2 sides. The relationship between these circumferential gaps (hereinafter referred to simply as "gap") is set as follows.

[0106] θ2<θ3

[0107] By setting the gap as described above, before the torsion angle between the input side plate 21 and the hub flange 22 (hereinafter, referred to as "torsion angle," it is the torsion angle between the input side plate 21 and the hub flange 22) reaches θ2, only the large coil spring 47 is compressed, and the resin component 48 is not compressed. Furthermore, when the torsion angle exceeds θ2, the resin component 48 is compressed between the R2-side pressing surface 21d of the second window portion 21b of the input side plate 21 and the R1-side pressing surface 41f of the second window opening 41b of the flange 40. Therefore, as... Figure 11 As shown, the torsional characteristics on the positive side become characteristic C2 when the torsional angle is between θ1 and θ2, and become characteristic C3 when the torsional angle exceeds θ2.

[0108] In addition, when the torsion angle becomes θ3, the stop pin 24 abuts against the end face of the R1 side of the first stop hole 42a, thereby restricting the relative rotation between the input side plate 21 and the hub flange 22.

[0109] <Negative-side torsional characteristics>

[0110] The torsional characteristics of the negative side of the damping unit 20, i.e., the characteristics when torque is input from the drive unit side in the opposite direction (input of negative side torque), will be explained.

[0111] As described in the positive torsion characteristics, when the torsion angle is less than angle -θ1, the large helical spring 47 does not move (is not compressed), and the input side plate 21 rotates integrally with the flange 40.

[0112] In this case, the hub 30 rotates relative to the flange 40 towards the R1 side, the first small coil spring 53 of the pre-damper 50 is further compressed, and the second small coil spring 54 is extended. Therefore, as Figure 11 As shown, a low-stiffness torsional characteristic C1 can be obtained before the torsion angle becomes -θ1. It should be noted that although the second small helical spring 54 is extended, it remains compressed at the torsion angle of -θ1 and does not extend to a free state. Furthermore, here, since the hub 30 and flange 40 rotate relative to each other, a relatively small first hysteresis torque is generated.

[0113] When the torsion angle becomes angle -θ1, the tooth 30a of the hub 30 abuts against the end face of the engagement hole 43a of the flange 40. Therefore, the hub 30 and flange 40 rotate as a unit, and the two small helical springs 53 and 54 stop moving. In this case, the large helical spring 47 is compressed between the second spring seat 72 mounted on the R2 side pressing surface 41c of the first window hole 41a of the hub flange 22 and the first spring seat 71 mounted on the R1 side pressing surface 21c of the first window portion 21a of the input side plate 21.

[0114] The operation of resin component 48 is the same as when a positive torque is input. That is, it is not compressed before the torsion angle becomes -θ2, and when the torsion angle is below -θ2, it is as follows: Figure 11 As shown, this results in a low-rigidity torsional characteristic C2. Furthermore, when the torsion angle is -θ2, the resin component 48 begins to be compressed between the R2-side pressing surface 41f of the second window opening 41b of the hub flange 22 and the R1-side pressing surface 21d of the second window portion 21b of the input side plate 21. Therefore, when the torsion angle exceeds -θ2, as... Figure 11 As shown, it exhibits high torsional rigidity, C3.

[0115] When the torsion angle becomes -θ3, the stop pin 24 abuts against the R2 side end face of the second stop hole 42b, thereby restricting the relative rotation between the input side plate 21 and the hub flange 22.

[0116] [feature]

[0117] (1) In the pre-damper 50, two small helical springs 53 and 54 are configured in a compressed state and exert force on the flange 40 in different rotational directions relative to the hub 30. Therefore, at idle speed, etc., abnormal noise caused by the gap between the hub 30 and the flange 40 can be suppressed.

[0118] (2) In the input side plate 21, the circumferential length of the second window portion 21b is made longer than the width of the resin component 48. Therefore, the circumferential length of the second window opening 41b of the flange 40 can be the same as that of the resin component 48. As a result, space can be ensured in the flange 40 for arranging the pre-damper 50 with its characteristic structure.

[0119] (3) A recess 711a is formed in the first spring seat 71, and a protrusion 41d formed in the first window hole 41a of the flange 40 is inserted into the recess 711a. In addition, the end of the first stop hole 42a extends toward the protrusion 41d. Therefore, the circumferential length of the first stop hole 42a can be increased. That is, compared with the case where the spring seat has no recess and the end face of the window hole is formed by a plane (the case without the protrusion), the torsional angle between the input side plate 21 and the hub flange 40 can be increased (i.e., widened).

[0120] (4) The end of the second stop hole 42b on the side of the first window hole 41a is connected to the first window hole 41a. Therefore, the circumferential length of the second stop hole 42b can be increased, and the torsion angle between the input side plate 21 and the hub flange 22 can be increased.

[0121] (5) For the same reasons as above, the stop holes 42a and 42b on both sides of the first window hole 41a of the flange 40 can be brought close to each other. As a result, the angle formed by the stop pins 24 on both sides of the first window hole 41a and the rotation shaft O can be close to 90°, which can suppress the unevenness of the strength of the input side plate 21 and the hub flange 22.

[0122] (6) Since one end of the first window hole 41a is not connected to the first stop hole 42a, the reduction in the strength of the flange 40 can be suppressed.

[0123] [Other Implementation Methods]

[0124] This invention is not limited to the embodiments described above, and various modifications or alterations can be made without departing from the scope of this invention.

[0125] (a) In the described embodiment, the invention is applied to a vibration damping device having three levels of torsional characteristics, but the invention can also be applied to a device having two levels of torsional characteristics. In this case, the second window 21b, the second window opening 41b, and the resin component 48 are not required in the described embodiment.

[0126] (b) In the embodiment described above, spring seats 71 and 72 are provided at both ends of the large helical spring 47, but these spring seats may not be provided. Alternatively, a spring seat may be provided only at one end of the large helical spring 47.

[0127] (c) The structure of the elastic components is not limited to two helical springs and two resin components. For example, all the elastic components can be helical springs, and the number is not limited.

[0128] (d) In the described embodiment, the present invention is applied to a vibration damping device with a torque limiter, but it can also be applied to other vibration damping devices in the same way.

[0129] (e) Torsional properties are not limited to Figure 11 The characteristics shown.

[0130] Explanation of reference numerals in the attached figures

[0131] 21…Input side plate (first rotating body); 22…Hub flange (second rotating body); 24…Stop pin; 30…Hub; 30a…Gear (first engaging part); 30b…Protrusion (support part); 40…Flange; 41a…First window hole; 42a…First stop hole (first cut); 42b…Second stop hole (second cut); 43a…Engaging hole (second engaging part); 43b…Retaining cut; 45…Stop mechanism; 47…Large coil spring (first and third main elastic components); 48…Resin component (second and fourth main elastic components); 50…Pre-damper; 53, 54…First and second small coil springs (first and second auxiliary elastic components).

Claims

1. A vibration damping device, comprising: First body of revolution; The second rotating body has a cylindrical hub and a flange disposed on the outer periphery of the hub in a manner that allows it to rotate relative to the hub. The second rotating body is capable of rotating relative to the first rotating body. The first pre-damper elastically connects the hub and the flange in the rotational direction and operates within the first torsional angle region between the first rotating body and the second rotating body; as well as A first primary elastic component is positioned at a different location in the circumferential direction from the first pre-damper, and elastically connects the first rotating body and the second rotating body in the rotational direction. The first primary elastic component operates within a second torsion angle region that is larger than the first torsion angle region. The first pre-damper has a first elastic component and a second elastic component. The first elastic member is configured in a compressed state when the hub and the flange are in a neutral position without relative rotation, and applies force to the flange relative to a first side of the hub in the rotation direction. The second elastic member is configured in a compressed state when neutral, applying force to the flange relative to the second side in the hub rotation direction. The flange has a first window opening for receiving the first main elastic component. The vibration damping device also includes a stop mechanism that limits the relative rotation angle between the first rotating body and the second rotating body to a predetermined angle range. The stopping mechanism has a first cut and a second cut formed on the flange and two stopping components fixed to the first rotating body. The first cut is formed by extending circumferentially on one side of the first window opening. The second cut is a hole formed by extending circumferentially on the other side of the first window opening, and communicates with the first window opening near its end. The two stop components are capable of moving circumferentially within the first cut and the second cut. The first cut is provided separately from the first window opening.

2. The vibration damping device according to claim 1, wherein, As the hub rotates relative to the flange on a first side in the rotational direction, the first elastic member is further compressed. As the hub rotates relative to the flange on the second side in the rotational direction, the second secondary elastic member is further compressed.

3. The vibration damping device according to claim 1 or 2, wherein, When the hub rotates relative to the flange on the second side in the rotational direction, the first elastic member extends. When the hub rotates relative to the flange on the first side in the rotational direction, the second elastic member extends.

4. The vibration damping device according to claim 1 or 2, wherein, The hub has multiple first engaging portions and supporting portions on its outer peripheral surface. The flange has a plurality of second engaging portions and a retaining slit on its inner circumferential surface. The plurality of second engaging portions are spaced apart in the circumferential direction and are opposite to the plurality of first engaging portions. The retaining slit has a predetermined width and is inserted into the support portion. The first elastic component is installed in a compressed state between one end of the support portion and the retaining notch. The second elastic component is installed in a compressed state between the support portion and the other end of the retaining cutout.

5. The vibration damping device according to claim 1, wherein, The first cut is formed in an arc shape on the first pitch radius. The second cut is an arc-shaped hole formed on a second pitch radius that is closer to the inner circumference than the first pitch radius.

6. The vibration damping device according to claim 5, wherein, The first window opening has a protrusion on a circumferential pressing surface, the protrusion bulging outwards in the circumferential direction at the radial center of the pressing surface. The end of the first cut near the first window hole extends toward the protrusion.

7. The vibration damping device according to claim 1 or 2, wherein, The vibration damping device further includes a second main elastic component, which is disposed radially outside the first pre-damper and elastically connects the first rotating body and the second rotating body in the rotational direction. The first rotating body has a pair of windows that are longer in the circumferential direction than the second main elastic component. The flange has a pair of windows that house the second main elastic component.

8. The vibration damping device according to claim 7, wherein, The vibration damping device also includes: The second pre-damper is disposed opposite to the first pre-damper across the rotation axis of the first rotating body, and together with the first pre-damper, elastically connects the hub and the flange in the rotational direction; The third main elastic component is disposed opposite to the first main elastic component across the rotation axis of the first rotating body, and together with the first main elastic component, elastically connects the first rotating body and the second rotating body in the rotation direction; as well as The fourth main elastic component is positioned opposite the second main elastic component across the rotation axis of the first rotating body and is arranged radially outside the second pre-damping device, and together with the second main elastic component, elastically connects the first rotating body and the second rotating body in the rotation direction.

Images