Power transmission device

Abstract

The utility model provides a power transmission device which can realize low cost. The torque limiting unit includes a flywheel, a friction plate, a pressure plate, and a biasing member. The flywheel includes a base portion and a support portion. The base portion includes a through hole penetrating in the axial direction. The support portion is disposed on a first side in the axial direction with a gap from the base portion. The damping unit is attached to the torque limiting unit. The damper unit has an input rotating body, an output rotating body, and an elastic member. The first fastening member fastens the friction plate and the input rotating body. The first fastening member is configured to be exposed in the axial direction via the through hole.

Description

Technical Field

[0001] This utility model relates to a power transmission device. Background Technology

[0002] The power transmission device is configured to absorb torque fluctuations from the engine. This power transmission device includes a flywheel, a torque limiting unit, and a damping unit (e.g., Patent Document 1). The damping unit is mounted on the flywheel via the torque limiting unit. The torque limiting unit is configured to limit the transmission of torque exceeding a predetermined value between the flywheel and the damping unit.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2021-55810 Utility Model Content

[0006] Technical problem to be solved by the utility model

[0007] The goal is to reduce the cost of power transmission devices configured as described above. Therefore, the objective of this invention is to provide a power transmission device that can achieve cost reduction.

[0008] The power transmission device according to the first embodiment includes a torque limiting unit, a vibration damping unit, and a first fastening member. The torque limiting unit includes a flywheel, a friction plate, a pressure plate, and a force-applying member. The flywheel has a base portion and a support portion. The base portion includes a through hole that extends axially. The support portion is spaced apart from the base portion and disposed on a first axial side. The friction plate is disposed between the base portion and the support portion. The pressure plate presses against the friction plate. The force-applying member applies force to the pressure plate toward the friction plate. The vibration damping unit includes an input rotating body, an output rotating body, and an elastic member. The input rotating body is configured to rotate integrally with the friction plate. The output rotating body is configured to rotate relative to the input rotating body. The elastic member elastically connects the input rotating body and the output rotating body. The first fastening member fastens the friction plate to the input rotating body. The first fastening member is configured to be exposed axially via the through hole.

[0009] According to this structure, by using a flywheel as a component of the torque limiting unit, the number of parts can be reduced, thereby achieving cost reduction. Moreover, since a through hole is formed in the flywheel to expose the first fastening member, the torque limiting unit and the vibration damping unit, including the flywheel, can be fastened together by the first fastening member after they are assembled separately.

[0010] The power transmission device according to the second embodiment is configured as follows, in the power transmission device according to the first embodiment: The input rotating body has a second fastening member and a pair of input plates. The second fastening member fastens the pair of input plates at the outer periphery of the pair of input plates. The second fastening member is disposed on a first side in the axial direction relative to the support portion. When viewed in the axial direction, the second fastening member overlaps with the support portion.

[0011] The power transmission device involved in the third embodiment is configured as follows, in the power transmission device involved in the first or second embodiment: The base portion has an engaging hole. The pressure plate has engaging claws that engage with the engaging hole.

[0012] The power transmission device according to the fourth embodiment is configured as follows, in the power transmission device according to the third embodiment: The pressure plate has an annular main body. Engaging claws extend axially from the inner peripheral end of the main body to a second side.

[0013] The power transmission device involved in the fifth embodiment is configured as follows in the power transmission device involved in the fourth embodiment: The force-applying member is a coil spring. The force-applying member has an inner peripheral end and an outer peripheral end, the inner peripheral end abutting against the pressure plate, and the outer peripheral end abutting against the base portion.

[0014] The power transmission device involved in the sixth embodiment is configured as follows, as in the power transmission devices involved in any of the first to fifth embodiments: The friction plate is sandwiched between a support and a pressure plate.

[0015] The power transmission device according to the seventh embodiment is configured as follows, as described in any of the power transmission devices according to the first to sixth embodiments: The support portion has a threaded hole that extends axially. The force-applying member is exposed axially via the threaded hole.

[0016] The method for manufacturing the power transmission device involved in the eighth method is a method for manufacturing the power transmission device involved in any of the first to seventh methods. The manufacturing method includes: assembling a torque limiting unit, assembling a vibration damping unit, and fastening a friction plate to an input rotating body via a through hole.

[0017] According to this utility model, a power transmission device that can achieve low cost can be provided. Attached Figure Description

[0018] Figure 1 This is the front view of the power transmission device.

[0019] Figure 2 yes Figure 1 Sectional view along line II-II.

[0020] Figure 3 This is a cross-sectional view of the power transmission device before assembly.

[0021] Figure 4 This is a cross-sectional view of a power transmission device in a state where the force of the coil spring is rendered ineffective. Detailed Implementation

[0022] Hereinafter, the power transmission device 100 according to this embodiment will be described with reference to the accompanying drawings. In the following description, the axial direction is the direction in which the rotation axis O of the power transmission device 100 extends. Furthermore, the circumferential direction is the circumferential direction of a circle centered on the rotation axis O, and the radial direction is the radial direction of a circle centered on the rotation axis O. Additionally, the first side of the axial direction refers to... Figure 2 The right side, the second side of the axis refers to Figure 2 On the left side.

[0023] Figure 1 This is the front view of the power transmission device 100. Figure 2 yes Figure 1 Sectional view along line II-II. (See also...) Figure 1 as well as Figure 2 As shown, the power transmission device 100 includes a torque limiting unit 3, a vibration damping unit 4, and a first fastening member 5. The torque limiting unit 3 and the vibration damping unit 4 rotate substantially integrally with each other. The power transmission device 100 is disposed between an internal combustion engine (not shown) and an output-side component (not shown). The output-side component may be, for example, an electric motor or a transmission. The power transmission device 100 is mounted on a crankshaft (not shown). For example, Figure 2 In this configuration, the internal combustion engine is positioned on the left side of the power transmission device 100, and the output-side component is positioned on the right side of the power transmission device 100. The power transmission device 100 is configured to limit the torque transmitted between the internal combustion engine and the output-side component and to attenuate torque fluctuations.

[0024] [Vibration Reduction Unit]

[0025] The vibration damping unit 4 is mounted to the torque limiting unit 3 via the first fastening member 5. The vibration damping unit 4 is configured to attenuate rotational fluctuations. The vibration damping unit 4 has an input rotating body 41, an output rotating body 42, and a plurality of elastic members 43.

[0026] <Input Rotation Solid>

[0027] The input rotating body 41 rotates integrally with the friction plate 32 of the torque limiting unit 3 (described later). The input rotating body 41 has a pair of input plates 41a and 41b. Specifically, the input rotating body 41 has a first input plate 41a and a second input plate 41b. Both the first input plate 41a and the second input plate 41b are annular components with a central hole. The first input plate 41a and the second input plate 41b rotate integrally with each other. Furthermore, the first input plate 41a and the second input plate 41b cannot move relative to each other in the axial direction.

[0028] The first input plate 41a and the second input plate 41b are spaced apart from each other in the axial direction. The first input plate 41a is positioned on the first side in the axial direction relative to the second input plate 41b.

[0029] The first input panel 41a and the second input panel 41b each have a plurality of windows 411a and 411b. In addition, in this embodiment, the first input panel 41a and the second input panel 41b each have four windows 411a and 411b, but their number is not limited to this.

[0030] The windows 411a and 411b are spaced apart from each other in the circumferential direction. Each window 411a and 411b is configured to accommodate an elastic member 43.

[0031] The input rotating body 41 also has a plurality of second fastening members 41c. The second fastening members 41c fasten the first input plate 41a and the second input plate 41b at the outer periphery of the first input plate 41a and the second input plate 41b.

[0032] The second fastening member 41c is disposed on a first side in the axial direction relative to the support portion 312, which will be described later. When viewed in the axial direction, the second fastening member 41c overlaps with the support portion 312. The second fastening member 41c is, for example, a rivet.

[0033] <Output Rotational Body>

[0034] The output rotating body 42 is configured to transmit torque from the input rotating body 41 to the output-side component. The output rotating body 42 is axially disposed between the first input plate 41a and the second input plate 41b. The output rotating body 42 is configured to be rotatable relative to the first input plate 41a and the second input plate 41b.

[0035] The output rotating body 42 has a hub 421 and a flange plate 422. The hub 421 and the flange plate 422 are constructed as separate components, but they can also be constructed as a single component. The hub 421 and the flange plate 422 rotate as a single unit.

[0036] The hub 421 is cylindrical and is disposed within the central holes of the first input plate 41a and the second input plate 41b. An axially extending spline hole is formed on the inner circumference of the hub 421. The input shaft of the output-side component can be splined into this spline hole.

[0037] A flange plate 422 extends radially from the outer peripheral surface of the hub 421. The flange plate 422 is formed in an annular shape. The flange plate 422 is configured to rotate relative to the first input plate 41a and the second input plate 41b. The flange plate 422 is axially disposed between the first input plate 41a and the second input plate 41b.

[0038] The flange plate 422 has a plurality of receiving holes 423. In this embodiment, the flange plate 422 has four receiving holes 423, but this number is not limited to this. The receiving holes 423 are spaced apart from each other in the circumferential direction. Each receiving hole 423 is configured to receive an elastic member 43. When viewed axially, each receiving hole 423 is positioned to overlap with each window portion 411a, 411b.

[0039] <Elastic Components>

[0040] The elastic member 43 is configured to elastically connect the input rotating body 41 and the output rotating body 42 in the rotational direction. The elastic member 43 is, for example, a helical spring.

[0041] The elastic member 43 is received in the receiving hole 423 of the output rotating body 42. In addition, the elastic member 43 is received in the window 411a of the first input plate 41a and also in the window 411b of the second input plate 41b.

[0042] [Torque Limiter]

[0043] like Figure 2 As shown, the torque limiting unit 3 is configured to rotate about the rotation axis O. The torque limiting unit 3 is positioned on the second axial side relative to the damping unit 4. The torque limiting unit 3 is annular. The torque limiting unit 3 is mounted to the crankshaft by a plurality of bolts 101. Furthermore, each bolt 101 is exposed on the first axial side. That is, each component constituting the damping unit 4 has through holes or cutouts, etc., in a manner that does not overlap with the bolts 101 when viewed axially.

[0044] The torque limiting unit 3 is configured to limit the torque transmitted between the crankshaft and the damping unit 4. That is, the torque limiting unit 3 is configured to limit the transmission of torque exceeding a predetermined value in the power transmission device 100.

[0045] The torque limiting unit 3 includes a flywheel 31, a friction plate 32, a first friction material 33a, a second friction material 33b, a pressure plate 34, and a coil spring 35 (an example of a force-applying component).

[0046] <Flywheel>

[0047] The flywheel 31 is mounted to the crankshaft by multiple bolts 101. The flywheel 31 rotates integrally with the crankshaft.

[0048] The flywheel 31 has a base portion 311 and a support portion 312. The support portion 312 is mounted to the base portion 311 by a plurality of bolts 102. The support portion 312 rotates integrally with the base portion 311.

[0049] The base portion 311 is a circular plate with an opening in the center. The base portion 311 has multiple through holes 311a and multiple engaging holes 311b. The through holes 311a are spaced apart from each other in the circumferential direction. Each through hole 311a penetrates the base portion 311 in the axial direction.

[0050] The engagement holes 311b are spaced apart from each other in the circumferential direction. Each engagement hole 311b penetrates the base portion 311 in the axial direction.

[0051] The support portion 312 is annular, extending circumferentially. The support portion 312 is disposed on a first axial side relative to the base portion 311. The support portion 312 is axially spaced apart from the base portion 311. Specifically, the inner periphery of the support portion 312 is axially spaced apart from the base portion 311. The outer periphery of the support portion 312 contacts the base portion 311. The support portion 312 is mounted to the base portion 311 at its outer periphery.

[0052] The support portion 312 has a threaded hole 312a. The threaded hole 312a extends axially through the inner periphery of the support portion 312. The threaded hole 312a forms an opening in the space between the inner periphery of the support portion 312 and the base portion 311. The disc spring 35, described later, is exposed on a first axial side through this threaded hole 312a. That is, the threaded hole 312a faces the disc spring 35 axially.

[0053] A friction plate 32, a first friction material 33a, a second friction material 33b, a pressure plate 34, and a coil spring 35 are disposed between the base portion 311 and the support portion 312. The thickness of the support portion 312 is greater than the thickness of the base portion 311.

[0054] <Friction Plate>

[0055] The friction plate 32 is an annular plate. The friction plate 32 is configured to rotate about the rotation axis O. The friction plate 32 is axially positioned between the base portion 311 and the support portion 312. Specifically, the friction plate 32 is sandwiched between the pressure plate 34 and the support portion 312. The friction plate 32 engages with the support portion 312 through a first friction material 33a. Furthermore, the friction plate 32 engages with the pressure plate 34 through a second friction material 33b.

[0056] Friction plate 32 is mounted on input rotating body 41. More specifically, friction plate 32 is mounted on second input plate 41b. Friction plate 32 is mounted on second input plate 41b by first fastening member 5. Friction plate 32 rotates integrally with input rotating body 41.

[0057] <Friction Materials>

[0058] The first friction material 33a is an annular shape extending circumferentially. The first friction material 33a is disposed on a first side in the axial direction relative to the friction plate 32. That is, the first friction material 33a is axially disposed between the friction plate 32 and the support portion 312. The first friction material 33a is mounted on the friction plate 32. The first friction material 33a rotates integrally with the friction plate 32.

[0059] The second friction material 33b is an annular shape extending circumferentially. The second friction material 33b is disposed on a second side in the axial direction relative to the friction plate 32. That is, the second friction material 33b is disposed axially between the friction plate 32 and the base portion 311. More specifically, the second friction material 33b is disposed between the friction plate 32 and the pressure plate 34. The second friction material 33b is mounted on the friction plate 32. The second friction material 33b rotates integrally with the friction plate 32.

[0060] <Pressure plate>

[0061] The pressure plate 34 is annular, extending in the circumferential direction. The pressure plate 34 is configured to press against the friction plate 32. The pressure plate 34 presses against the friction plate 32 through the second friction material 33b. The pressure plate 34 is axially positioned between the second friction material 33b and the disc spring 35.

[0062] The pressure plate 34 is configured to rotate integrally with the base portion 311. Specifically, the pressure plate 34 has a main body portion 341 and a plurality of engaging claws 342. The main body portion 341 is annular in the circumferential direction. Each engaging claw 342 extends from the inner circumferential end of the main body portion 341 toward a second side in the axial direction. Each engaging claw 342 engages with each engaging hole 311b. That is, each engaging claw 342 extends within each engaging hole 311b. Therefore, the pressure plate 34 rotates integrally with the base portion 311. Furthermore, the pressure plate 34 is axially movable relative to the base portion 311.

[0063] <Coiled Spring>

[0064] A coil spring 35 is axially positioned between the base portion 311 and the pressure plate 34. The coil spring 35 exerts a force on the pressure plate 34 toward the friction plate 32. That is, the coil spring 35 exerts a force on the pressure plate 34 toward the first axial side. Thus, the friction plate 32, the first friction material 33a, and the second friction material 33b are clamped together by the pressure plate 34 and the support portion 312.

[0065] The coil spring 35 is a ring extending circumferentially. The coil spring 35 has an outer circumferential end and an inner circumferential end. The coil spring 35 abuts against the base portion 311 at its outer circumferential end and against the pressure plate 34 at its inner circumferential end. The outer diameter of the coil spring 35 is larger than the outer diameter of the pressure plate 34. Therefore, the coil spring 35 is exposed on a first axial side via the threaded hole 312a of the support portion 312. That is, the coil spring 35 faces the threaded hole 312a axially.

[0066] <First Fastening Component>

[0067] The first fastening member 5 fastens the friction plate 32 to the input rotating body 41. Specifically, the first fastening member 5 fastens the friction plate 32 to the second input plate 41b. The first fastening member 5 is configured to be exposed on a second side in the axial direction via a through hole 311a. That is, the first fastening member 5 faces the through hole 311a in the axial direction. The through hole 311a has a size such that the entire first fastening member 5 is exposed when viewed in the axial direction. In other words, the first fastening member 5 is entirely exposed on a second side in the axial direction via the through hole 311a. Furthermore, the first fastening member 5 is also exposed on a first side in the axial direction. That is, each component constituting the vibration damping unit 4 has a through hole or cutout in a manner that does not overlap with the first fastening member 5 when viewed in the axial direction. The first fastening member 5 is, for example, a rivet.

[0068] <Manufacturing Method>

[0069] Next, the manufacturing method of the power transmission device 100 configured as described above will be explained. First, as Figure 3 As shown, the torque limiting unit 3 and the vibration damping unit 4 are assembled separately. Then, the assembled torque limiting unit 3 and the vibration damping unit 4 are combined together.

[0070] In detail, the friction plate 32 of the torque limiting unit 3 is fastened to the input rotating body 41 (particularly the second input plate 41b) of the vibration damping unit 4 by the first fastening member 5. At this time, the fastening operation by the first fastening member 5 (e.g., the operation of flattening the head of the first fastening member 5) is performed via the through hole 311a formed in the base portion 311. The power transmission device 100 manufactured in this way is mounted to the crankshaft by bolts 101.

[0071] If the power transmission device 100 manufactured as described above is used, the torque limiting function of the torque limiting unit 3 will function, thereby causing the torque limiting unit 3 to rotate relative to the vibration damping unit 4, and the position of the first fastening member 5 and the through hole 311a to deviate. That is, sometimes the first fastening member 5 is not exposed on the second axial side through the through hole 311a. Therefore, when disassembling the power transmission device 100 for maintenance or other purposes, it is necessary to align the first fastening member 5 with the through hole 311a.

[0072] In this case, such as Figure 4As shown, firstly, the bolt 103 is screwed into the threaded hole 312a of the support portion 312, and the front end of the bolt 103 is pressed against the disc spring 35 in the axial direction to the second side. That is, the bolt 103 presses the disc spring 35 away from the pressure plate 34. As a result, the force of the disc spring 35 relative to the pressure plate 34 is released, and the clamping of the friction plate 32 by the pressure plate 34 is also released. As a result, the vibration damping unit 4 can be easily rotated relative to the torque limiting unit 3, thereby enabling the alignment of the first fastening member 5 with the through hole 311a.

[0073] [Variation Example]

[0074] The embodiments of this utility model have been described above, but this utility model is not limited to these descriptions. Various modifications can be made as long as they do not depart from the spirit of this utility model. In addition, the following variations can be applied substantially simultaneously.

[0075] (a) In the above embodiment, the friction plate 32 is frictionally engaged with the support portion 312, but the structure of the friction plate 32 is not limited thereto. For example, the friction plate 32 may also be frictionally engaged with the base portion 311. That is, the friction plate 32 may also be frictionally engaged with the base portion 311 through the second friction material 33b. In this case, the pressure plate 34 is disposed between the support portion 312 and the friction plate 32, and the coil spring 35 is disposed between the support portion 312 and the pressure plate 34. Moreover, the coil spring 35 applies force to the pressure plate 34 toward the second axial side.

[0076] (b) In the above embodiment, the support portion 312 is constituted by a component separate from the base portion 311, but the structure of the flywheel 31 is not limited to this. For example, the support portion 312 may be integrally formed with the base portion 311 by a single component.

[0077] (c) The coil spring 35 may not be exposed from the screw hole 312a. In this case, the pressure plate 34 can be configured to be exposed from the screw hole 312a. By pressing the pressure plate 34 with the bolt 103, the force of the coil spring 35 relative to the friction plate 32 can be nullified, and the damping unit 4 can be easily rotated relative to the torque limiting unit 3.

[0078] Explanation of reference numerals in the attached figures

[0079] 3...Torque limiting unit; 31...Flywheel; 311...Base part; 311a...Through hole; 311b...Engaging hole; 312...Support part; 312a...Screw hole; 32...Friction plate; 34...Pressure plate; 341...Main body part; 342...Engaging claw; 35...Coil spring; 4...Vibration damping unit; 41...Input rotating body; 41a...First input plate; 41b...Second input plate; 41c...Second fastening member; 42...Output rotating body; 43...Elastic member; 5...First fastening member; 100...Power transmission device.

Claims

1. A power transmission device characterized by comprising: Possessing: a torque limiting unit, a damping unit, and a first fastening member, The torque limiting unit has: A flywheel having a base portion and a support portion, the base portion including a through-hole that passes through in the axial direction, the support portion being disposed at the first side in the axial direction apart from the base portion by a spacing; A friction plate disposed between the base portion and the support portion; A pressing plate that presses the friction plate; and A force applying member that applies a force to the pressing plate toward the friction plate, The damping unit has: An input rotating body configured to rotate integrally with the friction plate; An output rotating body configured to be relatively rotatable with the input rotating body; And An elastic member that elastically links the input rotating body and the output rotating body, The first fastening member fastens the friction plate and the input rotating body, and the first fastening member is configured to be exposed in the axial direction via the through-hole.

2. The power transmission device according to claim 1, wherein The input rotating body has a second fastening member and a pair of input plates, the second fastening member fastening the pair of input plates at outer peripheral portions of the pair of input plates, The second fastening member is disposed at the first side in the axial direction with respect to the support portion, and overlaps the support portion when viewed in the axial direction.

3. The power transmission device according to claim 1, wherein The base portion has an engagement hole, The pressing plate has an engagement claw that engages with the engagement hole.

4. The power transmission device according to claim 3, wherein The pressing plate has a ring-shaped main body portion, The engagement claw extends from an inner peripheral end portion of the main body portion toward the second side in the axial direction.

5. The power transmission device according to claim 4, wherein The force applying member is a coil spring, The force applying member has an inner peripheral end portion that abuts against the pressing plate, and an outer peripheral end portion that abuts against the base portion.

6. The power transmission device according to claim 1, characterized in that The friction plate is sandwiched by the support portion and the pressing plate.

7. The power transmission device according to claim 1, characterized in that The support portion has a screw hole that passes through in the axial direction, The force applying member is exposed in the axial direction via the screw hole. ​

Images