Ratchet type clutch

Abstract

To provide a torque transmission direction switchable ratchet-type clutch which can prevent the damage of a switch plate, can suppress an increase of the weight of a device as a whole which is incorporated as a constituent, and can suppress an increase of an arrangement space of the device.SOLUTION: A ratchet-type clutch has a switch plate 51 which is arranged coaxially with an inner ring 5 and an outer ring 3, and so as to be relatively rotatable with the inner ring 5 and the outer ring 3, and a switch plate operation member 61 arranged coaxially with the switch plate 51, and rotatably supporting the switch plate 51. In a state that a first claw member 31 or a second claw member 37 is engaged with a tooth part 13 between an inside-diameter side member 65 to which the switch plate 51 is fixed and an outside-diameter side member 63, elastic bodies 77 which are shrinkable by the relative rotation of the switch plate 51 and the inside-diameter side member 65 with respect to the outside-diameter side member 63 are interposed in a plurality of pieces.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a torque transmission direction switching type ratchet clutch used as a device for torque transmission in vehicles, industrial machines, and the like.

Background Art

[0002] Conventionally, there is a clutch using a ratchet mechanism that can switch the torque transmission direction by switching between a state where only rotation in one or the other of the forward or reverse rotation directions with respect to the rotation direction of the inner ring member relative to the outer ring member or the outer ring member relative to the inner ring member is locked, a state where rotation in both the forward and reverse rotation directions is simultaneously locked, and a state where rotation in neither the forward nor reverse rotation direction is locked (see, for example, Patent Documents 1 and 2).

[0003] The clutches described in Patent Documents 1 and 2 switch the rotation transmission direction between the inner and outer rings, that is, the torque transmission direction, by displacing an annular switching plate whose engagement state with the ratchet mechanism can be changed by displacement, using an external device such as an actuator.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] In recent years, the electric control of transmission devices has become more complex. For this reason, in the clutches described in Patent Document 1 or 2, for example, when a sudden switching of the rotational direction occurs while a claw member and a mating tooth portion are engaged, the operation of the clutch cannot follow the switching control, and the switching plate starts to operate for disengagement control while the engagement between the claw member and the mating tooth portion remains un-released, which may cause the switching plate to be damaged. Due to such concerns, further complicating the control would lead to an increase in the number of control devices or a complication of the structure of the clutch itself, i.e., an increase in the number of parts. When the clutch is used as a component of a transmission device, there is a risk that the weight of the entire transmission device and the mounting space in the vehicle will increase. This may make it difficult to achieve the recent strict requirements for weight reduction and space saving.

[0006] The present invention has been made in view of such circumstances, and an object thereof is to provide a torque transmission direction switching type ratchet clutch that can prevent damage to the switching plate and suppress an increase in the weight of the entire device incorporated as a component and an increase in the arrangement space of the device.

Means for Solving the Problems

[0007] To solve the above problems, the ratchet clutch according to the present invention includes a first annular member, a second annular member arranged coaxially with and relatively rotatable with respect to the first annular member, a ratchet mechanism provided on the first annular member and the second annular member and capable of engaging the first annular member and the second annular member so as to transmit torque, a ratchet clutch having a switching mechanism capable of switching the torque transmission direction between the first annular member and the second annular member, wherein the switching mechanism includes a third annular member provided coaxially with the first and second annular members and relatively rotatable with respect to the first and second annular members, It has a fourth annular member that is arranged coaxially with the third annular member and rotatably supports the third annular member. The third annular member is formed with a limiting portion that can limit the engagement between the claw member and the tooth portion of the ratchet mechanism by contacting the claw member of the ratchet mechanism. The limiting portion switches between contact and non-contact with the claw member as the third annular member rotates. A plurality of elastic members that can be contracted by the relative rotation of the third annular member with respect to the fourth annular member are interposed between the third annular member and the fourth annular member in a state where the claw member is engaged with the tooth portion. 、 When the claw member is engaged with the tooth portion, the elastic member contracts when a torque greater than a predetermined value is transmitted from the claw member to the third annular member. It is characterized by this. Moreover, the ratchet type clutch according to the present invention a first annular member, a second annular member arranged coaxially with and relatively rotatable with respect to the first annular member, a ratchet mechanism provided on the first annular member and the second annular member and capable of engaging the first annular member and the second annular member so as to be able to transmit torque, a ratchet type clutch having a switching mechanism capable of switching the torque transmission direction between the first annular member and the second annular member, wherein the switching mechanism a third annular member provided coaxially with the first and second annular members and relatively rotatable with respect to the first and second annular members, a fourth annular member arranged coaxially with the third annular member and rotatably supporting the third annular member, a restricting portion capable of restricting the engagement between the claw member and the tooth portion of the ratchet mechanism is formed on the third annular member by contacting the claw member of the ratchet mechanism, the restricting portion switches between contact and non-contact with the claw member by the rotation of the third annular member, a plurality of elastic members capable of contracting by relative rotation of the third annular member with respect to the fourth annular member are interposed between the third annular member and the fourth annular member in a state where the claw member is engaged with the tooth portion, the third annular member has a peripheral surface facing the claw member in the radial direction, the restricting portion is a convex portion formed on the peripheral surface and displacing the claw member in a non-engaging direction with the tooth portion by contacting the claw member.

Advantages of the Invention

[0008] According to the present invention, it is possible to provide a torque transmission direction switching type ratchet clutch that can prevent damage to the switching plate and suppress an increase in the weight of the entire device incorporated as a component and an increase in the arrangement space of the device.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

MODE FOR CARRYING OUT THE INVENTION

[0010] Hereinafter, a torque transmission direction switching type ratchet type clutch according to an embodiment of the present invention will be described with reference to the drawings. The torque transmission direction switching type ratchet type clutch according to the present embodiment will be described as an example used as a component of a vehicle transmission. In the following description, the torque transmission direction switching type ratchet type clutch may be abbreviated as "ratchet type clutch".

[0011] First, the directions related to the switching ratchet-type clutch in this embodiment are defined. In this embodiment, the "central axis C" refers to the central axis of the switching ratchet-type clutch, that is, the central axis of the outer ring and the inner ring. The axial direction, radial direction, and circumferential direction refer to the axial direction, radial direction, and circumferential direction with respect to the central axis C. Also, for the axial direction, in FIG. 1, the left side of the paper surface is taken as one side of the axial direction, and the right side of the paper surface is taken as the other side of the axial direction. In FIGS. 2, 4 to 7, the front side of the paper surface is taken as one side of the axial direction, and the back side of the paper surface is taken as the other side of the axial direction. For the circumferential direction, in FIGS. 2, 4 to 7, the direction of rotation clockwise toward the paper surface is taken as one side of the circumferential direction, and the direction of rotation counterclockwise toward the paper surface is taken as the other side of the circumferential direction.

[0012] Regarding the rotation direction of the ratchet-type clutch, for the sake of convenience in explanation, the rotation direction of the inner ring with respect to the outer ring will be described. However, the rotation of the outer ring and the rotation of the inner ring are relative. For example, when the inner ring can rotate clockwise, the outer ring can also rotate counterclockwise. Also, even when the inner ring and the outer ring rotate in the same direction, if the rotation speeds of the outer ring and the inner ring are different, it can be said that the outer ring and the inner ring rotate relative to each other in one direction or the other.

[0013] FIG. 1 is a cross-sectional view along the axial direction of the switching ratchet-type clutch according to the embodiment. FIG. 2 is a front view showing the state of the main part of the switching ratchet-type clutch according to the embodiment as viewed from one side in the axial direction, showing one claw mechanism portion and its peripheral portion. FIG. 3 is a perspective view of the switching plate and the switching plate actuating member. The torque transmission direction switching ratchet-type clutch 1 according to this embodiment has an overall shape that is an annular shape similar to the shape shown in FIG. 2 of the above-mentioned Patent Document 2 when viewed from the axial direction, and includes a plurality of claw mechanism portions and a plurality of tooth portions. is FIG. 2 of the present application In [the figure], only one claw mechanism portion and its peripheral portion are shown.

[0014] The torque transmission direction switching type ratchet clutch 1 according to this embodiment includes an annular outer ring 3, an annular inner ring 5 that is spaced radially inward from the outer ring 3, is coaxial with the central axis C of the outer ring 3, and is rotatable relative to the outer ring 3, and a torque transmission mechanism that enables torque transmission between the outer ring 3 and the inner ring 5. The torque transmission mechanism in this embodiment is a ratchet mechanism.

[0015] The outer ring 3 is formed in a cylindrical shape having a predetermined length in the axial direction. A plurality of claw mechanism parts described later are held on the inner peripheral part of the outer ring 3. The outer ring 3 is fixed to the outer member so as not to be relatively rotatable by a fitting structure (not shown).

[0016] As shown in FIG. 2, on the inner peripheral part of the outer ring 3, a first claw member 31 and a second claw member 37 that is adjacent to the other side in the circumferential direction of the first claw member 31 and forms a pair with the first claw member 31 are provided. The first claw member 31 and the second claw member 37 constitute a claw mechanism part. That is, on the outer ring 3, a claw mechanism part including the first claw member 31 and the second claw member 37 that are arranged in pairs in order from one side in the circumferential direction to the other side in the circumferential direction when viewed from one side in the axial direction is provided. A plurality of such claw mechanism parts are provided on the outer ring 3 at predetermined intervals in the circumferential direction. The first claw member 31 has a claw part 29 extending from the cylindrical part 27 toward one side in the circumferential direction, and the second claw member 37 has a claw part 35 extending from the cylindrical part 33 toward the other side in the circumferential direction. A retainer 38 that rotatably holds the cylindrical part 27 of the first claw member 31 and the cylindrical part 33 of the second claw member 37 is fixed to the inner peripheral part of the outer ring 3 between the cylindrical part 27 of the first claw member 31 and the cylindrical part 33 of the second claw member 37. In this embodiment, a plurality of claw mechanism parts are provided at predetermined intervals in the circumferential direction, but only one claw mechanism part is shown in the figure 2 only shows one claw mechanism part.

[0017] The inner ring 5 is arranged radially inward of the outer ring 3. On the outer peripheral portion of the inner ring 5, a number of tooth portions 13 are formed at equal intervals over the entire circumference. Each tooth portion 13 projects radially outward and extends in the direction of the central axis C. The inner peripheral surface of the outer ring 3 and the outer peripheral portion of the inner ring 5, that is, the tooth portions 13, face each other radially with a predetermined space therebetween. The tooth portions 13 constitute ratchet teeth with which the first claw member 31 and the second claw member 37 mesh. Specifically, the side surface on the other side in the circumferential direction of each tooth portion 13 constitutes a first meshing portion 13a that meshes with the first claw member 31, and the side surface on one side in the circumferential direction of each tooth portion 13 constitutes a second meshing portion 13b that meshes with the second claw member 37.

[0018] On the inner peripheral surface of the inner ring 5, a spline 11 is provided over the entire circumference. On the inner peripheral side of the inner ring 5, a shaft member (not shown) for output or input is spline-fitted via the spline 11.

[0019] The first claw member 31 is held by a holding portion 39 and a retainer 38 formed on the inner peripheral portion of the outer ring 3 such that the claw portion 29 can swing radially about the cylindrical portion 27. The holding portion 39 is a recess that opens to one end face in the axial direction and the inner peripheral surface of the outer ring 3. Further, a coiled spring 41 is provided in the holding portion 39 that always biases the claw portion 29 of the first claw member 31 radially inward, that is, toward the outer peripheral surface of the inner ring 5. For example, in FIG. 2, when the inner ring 5 rotates counterclockwise, the claw portion 29 of the first claw member 31 meshes with the first meshing portion 13a of the tooth portion 13 of the inner ring 5. On the other hand, when the inner ring 5 rotates clockwise, the claw portion 29 of the first claw member 31 is pushed radially outward by the tooth portion 13 of the inner ring 5 against the biasing force of the spring 41, allowing the inner ring 5 to rotate. Thereby, the first claw member 31 locks the rotation of the inner ring 5 in the other direction in the circumferential direction and allows the rotation of the inner ring 5 in one direction in the circumferential direction.

[0020] The second claw member 37 is held by a holding portion 43 and a cage 38 formed on the inner peripheral portion of the outer ring 3 such that the claw portion 35 can swing in the radial direction about the cylindrical portion 33. The holding portion 43 is a recess that opens to one axial end surface and the inner peripheral surface of the outer ring 3. Further, a coiled spring 45 that always biases the claw portion 35 of the second claw member 37 radially inward, that is, toward the outer peripheral surface of the inner ring 5, is provided in the holding portion 43. For example, in FIG. 2, when the inner ring 5 rotates clockwise, the claw portion 35 of the second claw member 37 meshes with the second meshing portion 13b of the tooth portion 13 of the inner ring 5. On the other hand, when the inner ring 5 rotates counterclockwise, the claw portion 35 of the second claw member 37 is pushed radially outward by the tooth portion 13 of the inner ring 5 against the biasing force of the spring 45, allowing the rotation of the inner ring 5. Thereby, the second claw member 37 locks the rotation of the inner ring 5 in one circumferential direction and allows the rotation of the inner ring 5 in the other circumferential direction. In this way, the first claw member 31 and the second claw member 37 held by the holding portions 39 and 43 of the outer ring 3, the springs 41 and 45, and the tooth portion 13 formed on the inner ring 5 constitute a ratchet mechanism.

[0021] As shown in FIG. 1, an annular switching plate 51 is disposed coaxially with the outer ring 3 on the inner peripheral side of the outer ring 3. One axial end surface of the switching plate 51 faces the other axial end portion of the inner ring 5 axially. The outer peripheral surface of the switching plate 51 faces the inner peripheral surface of the outer ring 3, the surface on the inner diameter side of the first claw member 31, and the surface on the inner diameter side of the second claw member 37 with a predetermined space therebetween in the radial direction. A flange portion 53 that protrudes radially outward is formed at the outer edge portion of the other axial end surface of the switching plate 51. The outer edge portion of the flange portion 53 is engaged with the other axial portion of the inner peripheral surface of the outer ring 3 so as to be relatively rotatable. Thereby, the axial position of the switching plate 51 is positioned. One axial surface of the flange portion 53 faces the other axial end surface of the first claw member 31 and the other axial end surface of the second claw member 37 axially.

[0022] On the outer peripheral surface of the switching plate 51, as shown in FIG. 3, a plurality of convex portions 59 are provided at predetermined circumferential intervals. The convex portions 59 project radially outward and extend over a predetermined range in the circumferential direction. The top of the convex portion 59 is located slightly radially outward of the top of the tooth portion 13 of the inner ring 3, extends along the inner peripheral surface of the outer ring 3, and faces the inner peripheral surface of the outer ring 3 in the radial direction with a slight gap therebetween. That is, the top of the convex portion 59 is non-contact with the inner peripheral surface of the outer ring 3. Both circumferential ends of the top of the convex portion 59 are smoothly continuous with the outer peripheral surface of the switching plate 51 via inclined surfaces 60, respectively. With this configuration, the first claw member 31 and the second claw member 37 are smoothly pushed up from the outer peripheral surface of the switching plate 51 to the top of the convex portion 59 by the rotation of the switching plate 51.

[0023] When the top of the convex portion 59 is located on the inner diameter side of the first claw member 31 due to the rotation of the switching plate 51, it contacts the inner diameter side surface of the first claw member 31 and pushes up and holds the inner diameter side surface of the first claw member 31 to the outer diameter side of the tooth portion 13 of the inner ring 5. Thereby, the convex portion 59 restricts the meshing between the first claw member 31 and the tooth portion 13. Similarly, when the top of the convex portion 59 is located on the inner diameter side of the second claw member 37, it contacts the inner diameter side surface of the second claw member 37 and pushes up and holds the inner diameter side surface of the second claw member 37 to the outer diameter side of the tooth portion 13 of the inner ring 5, and thereby the convex portion 59 restricts the meshing between the second claw member 37 and the tooth portion 13. Thus, the convex portion 59 constitutes a pushing-up portion that pushes up and holds the first claw member 31 and the second claw member 37 to the outer diameter side.

[0024] By rotating the switching plate 51 in one circumferential direction or the other circumferential direction, the circumferential position of the convex portion 59 with respect to the claw mechanism portion is changed. Thereby, the combination state of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion, that is, the paired first claw member 31 and the second claw member 37, is changed. Specifically, the switching plate 51 switches four combination states of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion, and thereby switches the torque transmission direction of the ratchet type clutch 1.

[0025] The first combination state of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion is, as shown in FIG. 2, a state in which the convex portion 59 is not in contact with either the first claw member 31 or the second claw member 37 and faces the inner peripheral surface of the outer ring 3. In this state, the first claw member 31 and the second claw member 37 are respectively engaged with the tooth portion 13 of the inner ring 5 by the biasing forces of the springs 41 and 45. Therefore, in this state, the inner ring 5 is locked against rotation in either the circumferential one-way direction or the circumferential other-way direction with respect to the outer ring 3. That is, when the inner ring 5 is the input side, the inner ring 5 is in a locked state with respect to the outer ring 3 in both the circumferential one-way direction and the circumferential other-way direction.

[0026] The second combination state of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion is a state in which one convex portion 59 is in contact with the inner diameter side surface of the second claw member 37 and the convex portion 59 is not in contact with the first claw member 31. In this state, the convex portion 59 in contact with the second claw member 37 is in contact with the second claw member 37 in a state of compressing the spring 45, pushes up and holds the inner diameter side surface of the second claw member 37 to the outer diameter side of the tooth portion 13 of the inner ring 5, and restricts the engagement between the second claw member 37 and the tooth portion 13 of the inner ring 5. On the other hand, the first claw member 31 is engaged with the tooth portion 13 of the inner ring 5 by the biasing force of the spring 41. Therefore, in this state, the inner ring 5 is rotatable in the circumferential one-way direction with respect to the outer ring 3, and is locked against rotation in the circumferential other-way direction. That is, when the inner ring 5 is the input side, torque is transmitted from the inner ring 5 to the outer ring 3 in the circumferential other-way direction, and no torque is transmitted in the circumferential one-way direction.

[0027] The third combination state of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion is a state in which one convex portion 59 contacts the inner diameter side surface of the first claw member 31 and the convex portion 59 does not contact the second claw member 37. In this state, the protruding portion 59 that is in contact with the first claw member 31 contacts the first claw member 31 in a state where the spring 41 is compressed, pushes up and holds the inner diameter side surface of the first claw member 31 to the outer diameter side of the tooth portion 13 of the inner ring 5, and restricts the meshing between the first claw member 31 and the tooth portion 13 of the inner ring 5. On the other hand, the second claw member 37 is engaged with the tooth portion 13 of the inner ring 5 by the biasing force of the spring 45. Therefore, in this state, the inner ring 5 is rotatable in the other circumferential direction with respect to the outer ring 3, and is in a state where rotation in one circumferential direction is locked. That is, when the inner ring 5 is the input side, torque is transmitted from the inner ring 5 to the outer ring 3 in one circumferential direction, and no torque is transmitted in the other circumferential direction.

[0028] The fourth combination state of contact or non-contact of the convex portion 59 with respect to the claw mechanism portion is a state in which one convex portion 59 contacts the inner diameter side surface of the first claw member 31, and further, the one convex portion 59 or another one convex portion 59 contacts the inner diameter side surface of the second claw member 37. In this state, the convex portion 59 that is in contact with the first claw member 31 restricts the meshing between the first claw member 31 and the tooth portion 13 of the inner ring 5, and the convex portion 59 that is in contact with the second claw member 37 restricts the meshing between the second claw member 37 and the tooth portion 13 of the inner ring 5. Therefore, in this state, the inner ring 5 is not locked in either the circumferential one-way rotation or the circumferential other-way rotation with respect to the outer ring 3, and rotation in either the circumferential one-way or the circumferential other-way direction is possible. That is, when the inner ring 5 is the input side, no torque is transmitted from the inner ring 5 to the outer ring 3 in either the circumferential one-way or the circumferential other-way direction. The plurality of convex portions 59 of the switching plate 51 are designed with the circumferential length of the top of each and the circumferential interval between adjacent convex portions 59 so as to be able to switch the above four combination states with respect to the claw mechanism portion.

[0029] The switching plate 51 is rotatably supported by an annular switching plate actuating member 61. The switching plate actuating member 61 is arranged coaxially with the switching plate 51 on the other axial side of the switching plate 51. That is, the switching plate 51 and the switching plate actuating member 61 are arranged on the central axis C. The switching plate actuating member 61 has an annular outer diameter side member 63 and an annular inner diameter side member 65 which is arranged coaxially with and relatively rotatable with respect to the outer diameter side member 63 on the inner diameter side of the outer diameter side member 63.

[0030] On the end face on one axial side of the inner diameter side member 65, a plurality of protruding portions 67 protruding in one axial direction are formed at predetermined intervals in the circumferential direction. In the present embodiment, three protruding portions 67 are formed. In the switching plate 51, holes 69 that fit with the respective protruding portions 67 are formed at positions corresponding to the respective protruding portions 67 of the inner diameter side member 65. By fitting the holes 69 of the switching plate 51 and the protruding portions 67 of the inner diameter side member 65, the switching plate 51 is rotatably supported by the switching plate actuating member 61.

[0031] The outer diameter side member 63 is connected to a drive mechanism (not shown) in a transmission (not shown) in which the ratchet type clutch 1 is incorporated, and is rotationally driven by the drive mechanism. Here, as the drive mechanism in the transmission to which the outer diameter side member 63 is connected, for example, a linear motion mechanism, a rotational motion mechanism, or a mechanism combining a linear motion mechanism and a rotational motion mechanism can be used. Such a drive mechanism can be, for example, a worm gear (not shown) for switching gears in the transmission.

[0032] On the inner peripheral portion of the outer diameter side member 63, a plurality of notch portions 71 are formed which open to the inner peripheral surface and one end surface in the axial direction of the outer diameter side member 63 and extend over a predetermined length in the circumferential direction. In the present embodiment, six notch portions 71 are formed at predetermined intervals in the circumferential direction. On the other hand, on the outer peripheral portion of the inner diameter side member 65, a plurality of notch portions 73 are formed which open to the outer peripheral surface and one end surface in the axial direction of the inner diameter side member 65 and extend over a predetermined length in the circumferential direction. The notch portion 73 has the same circumferential length as the notch portion 71 of the outer diameter side member 63, and the same number as the notch portion 71 is formed at predetermined intervals in the circumferential direction. The notch portion 71 of the outer diameter side member 63 and the notch portion 73 of the inner diameter side member 65 face each other in the radial direction and form an elastic body accommodating portion 75 which is a space extending in the circumferential direction.

[0033] Inside each elastic body accommodating portion 75, an elastic body 77 is accommodated (see FIGS. 6 and 7). The elastic body 77 may use, for example, a coil spring or a leaf spring, and is not limited. The elastic body 77 is accommodated in the elastic body accommodating portion 75 so as to be stretchable and contractible in the circumferential direction in a natural state or a slightly compressed state. One end portion in the circumferential direction and the other end portion in the circumferential direction of the elastic body 77 are fixed to a support member 79 and a support member 81, respectively. The support member 79 and the support member 81 are, for example, columnar members and are formed to have a size slidable in the circumferential direction inside the elastic body accommodating portion 75.

[0034] In a natural state where the inner diameter side member 65 does not rotate relative to the outer diameter side member 63, one end surface in the circumferential direction of the support member 79 has its outer diameter side portion in contact with the one end surface in the circumferential direction of the notch portion 71 and its inner diameter side portion in contact with the one end surface in the circumferential direction of the notch portion 73 (see FIGS. 6 and 7). Also, the other end surface in the circumferential direction of the support member 81 has its outer diameter side portion in contact with the other end surface in the circumferential direction of the notch portion 71 and its inner diameter side portion in contact with the other end surface in the circumferential direction of the notch portion 73 (see FIGS. 6 and 7).

[0035] With such a configuration, when the inner diameter side member 65 and the switching plate 51 rotate relative to the outer diameter side member 63 in one circumferential direction, the end surface on the other circumferential side of the notch portion 73 of the inner diameter side member 65 moves to one circumferential side, so that the support member 81 moves in one circumferential direction within the elastic body accommodating portion 75, and the elastic body 77 contracts. Further, when the inner diameter side member 65 and the switching plate 51 rotate relative to the outer diameter side member 63 in the other circumferential direction, the end surface on the one circumferential side of the notch portion 73 of the inner diameter side member 65 moves to the other circumferential side, so that the support member 79 moves in the other circumferential direction within the elastic body accommodating portion 75, and the elastic body 77 contracts.

[0036] Next, the operation of the ratchet type clutch 1 will be described. The following description is about the meshing operation between the second claw member 37 and the tooth portion 13. The meshing operation between the first claw member 31 and the tooth portion 13 is the same as that of the second claw member 37, but the circumferential direction is opposite to that of the second claw member 37.

[0037] FIG. 4 is a front view showing a state in which a main part of the switching type ratchet type clutch according to the embodiment is viewed from one axial side, and shows the engage meshing state between the second claw member and the tooth portion. FIG. 5 is a front view showing a state in which a main part of the switching type ratchet type clutch according to the embodiment is viewed from one axial side, and shows the non- engage meshing state between the second claw member and the tooth portion. FIG. 6 is a front view showing a state in which the switching plate operating member is viewed from one axial side, and shows an operating state when the second claw member and the tooth portion are in a meshing state. FIG. 7 is a front view showing a state in which the switching plate operating member is viewed from one axial side, and shows an operating state when the second claw member and the tooth portion are in a non-meshing state.

[0038] As shown in Fig. 4, when the second claw member 37 and the tooth portion 13 are in a meshed state, the convex portion 59 of the switching plate 51 is adjacent to one axial side of the inner diameter side surface of the claw portion 35 of the second claw member 37. Specifically, the convex portion 59 is arranged in a state where the inclined surface 60 at the other circumferential side end of the convex portion 59 is in contact with the inner diameter side surface of the claw portion 35. In this state, as shown in Fig. 6, the inner diameter side member 65 rotates relative to the outer diameter side member 63 in one circumferential direction, and the elastic body 77 is contracted by a predetermined amount in the switching plate actuating member 61. Therefore, due to the elastic restoring force of the contracted elastic body 77, the switching plate 51 fixed to the inner diameter side member 65 is biased in the direction of rotating in the other circumferential direction with respect to the outer diameter side member 63. Due to this biasing force, the convex portion 59 of the switching plate 51 is biased in the direction of contacting the inner diameter side surface of the claw portion 35 of the second claw member 37.

[0039] In this state, when the inner ring 5 rotates in one circumferential direction, i.e., the clockwise direction, torque is transmitted to the outer ring 3 via the second claw member 37. At this time, the torque transmitted from the inner ring 5 to the second claw member 37 is also transmitted to the switching plate 51 in contact with the second claw member 37, and a force in the direction of rotating in one circumferential direction is applied to the switching plate 51. Here, the torque transmitted to the switching plate 51 is transmitted to the elastic body 77, and when the torque is greater than a predetermined value, i.e., greater than the elastic restoring force of the contracted elastic body 77, it is absorbed by the contraction of the elastic body 77. Even when an excessive torque greater than the normal torque is temporarily transmitted to the second claw member 37, the excessive torque is absorbed by the contraction of the elastic body 77. Therefore, since the switching plate 51 does not receive the torque transmitted from the second claw member 37, damage to the switching plate 51 can be prevented.

[0040] When the rotation direction of the inner ring 5 changes from the state where the second claw member 37 and the tooth portion 13 are engaged (FIG. 4), if the rotational speed of the inner ring 5 decreases, the torque transmitted from the inner ring 5 to the second claw member 37 also becomes smaller. When the magnitude of the torque transmitted from the inner ring 5 to the second claw member 37 becomes smaller than a predetermined value, that is, smaller than the elastic restoring force of the contracted elastic body 77, the elastic body 77 elastically returns and extends. As the elastic body 77 extends, the switching plate 51 rotates in the other circumferential direction, and the second claw member 37 is lifted and held at the top of the convex portion 59 via the inclined surface 60 of the convex portion 59. As a result, as shown in FIG. 5, the engagement between the second claw member 37 and the tooth portion 13 is released, and the inner ring 5 rotates idly with respect to the outer ring 3. That is, the ratchet type clutch 1 itself is in an idling state. In this state, as shown in FIG. 7, the inner diameter side member 65 does not rotate relative to the outer diameter side member 63 of the switching plate operating member 61, and the elastic body 77 is in a natural state or a slightly compressed state.

[0041] As described above, in the ratchet type clutch 1 of the present embodiment, since the torque transmitted to the switching plate 51 is absorbed by the contraction of the elastic body 77, damage to the switching plate 51 can be prevented. Further, since the elastic restoring force of the elastic body 77 can release the engaged state between the first claw member 31 or the second claw member 37 and the tooth portion 13, the control device can be simplified. As a result, according to the present embodiment, an increase in the weight of the entire device in which the ratchet type clutch 1 is incorporated as a component and an increase in the arrangement space of the device can be suppressed. If the device in which the ratchet type clutch 1 is incorporated as a component as in the present embodiment is a transmission of a vehicle, an increase in the weight of the entire transmission and an increase in the mounting space on the vehicle can be suppressed.

[0042] Note that the ratchet type clutch 1 of the present invention is not limited to the above embodiment and can be modified. For example, the claw mechanism portion may be provided on the inner ring side, and the tooth portion that meshes with the claw mechanism portion may be provided on the inner peripheral surface of the outer ring. Further, the number of claw mechanism portions can be appropriately changed according to the torque capacity to be transmitted.

Explanation of Reference Numerals

[0043] 1 Ratchet type clutch 3 Outer ring 5 Inner ring 13 Tooth part 31 First claw member 37 Second claw member 51 Switching plate 59 Protrusion 61 Switching plate actuating member 63 Outer diameter side member 65 Inner diameter side member 75 Elastic body accommodating part 77 Elastic body

Claims

1. a first annular member, a second annular member arranged coaxially with and rotatable relative to the first annular member, a ratchet mechanism provided on the first annular member and the second annular member and engageable with the first annular member and the second annular member to transmit torque, a ratchet type clutch having a switching mechanism capable of switching the torque transmission direction between the first annular member and the second annular member, wherein the switching mechanism a third annular member provided coaxially with the first and second annular members and rotatable relative to the first and second annular members, and a fourth annular member arranged coaxially with the third annular member and rotatably supporting the third annular member, a limiting portion capable of restricting the engagement between the claw member of the ratchet mechanism and the tooth portion is formed on the third annular member by contacting the claw member of the ratchet mechanism, the limiting portion switches between contact and non-contact with the claw member by rotation of the third annular member, a plurality of elastic members capable of contracting by relative rotation of the third annular member with respect to the fourth annular member are interposed between the third annular member and the fourth annular member in a state where the claw member is engaged with the tooth portion, the elastic member contracts when a torque greater than a predetermined value is transmitted from the claw member to the third annular member in a state where the claw member is engaged with the tooth portion, characterized in that the ratchet type clutch.

2. the elastic member extends when the torque transmitted to the claw member becomes smaller than the predetermined value in a state where the claw member is engaged with the tooth portion, and rotates the third annular member in a direction in which the limiting portion contacts the claw member, characterized in that the ratchet type clutch according to claim 1.

3. the third annular member has a circumferential surface facing the claw member in the radial direction, The limiting portion is a convex portion formed on the circumferential surface and displacing the claw member in a non-engaging direction with the tooth portion by contacting the claw member, and the ratchet type clutch according to claim 1 or 2 is characterized in that.

4. A first annular member, A second annular member coaxially and relatively rotatably arranged with the first annular member, A ratchet mechanism provided on the first annular member and the second annular member and capable of engaging the first annular member and the second annular member so as to transmit torque, A ratchet type clutch having a switching mechanism capable of switching the torque transmission direction between the first annular member and the second annular member, The switching mechanism is A third annular member coaxially provided with the first and second annular members and relatively rotatable with the first and second annular members, It has a fourth annular member coaxially arranged with the third annular member and rotatably supporting the third annular member, A limiting portion capable of restricting the engagement between the claw member and the tooth portion of the ratchet mechanism is formed on the third annular member by contacting the claw member of the ratchet mechanism, The limiting portion switches between contact and non-contact with the claw member by the rotation of the third annular member, A plurality of elastic members that can be contracted by the relative rotation of the third annular member with respect to the fourth annular member are interposed between the third annular member and the fourth annular member in a state where the claw member is engaged with the tooth portion, The third annular member has a circumferential surface facing the claw member in the radial direction, The limiting portion is a convex portion formed on the circumferential surface and displacing the claw member in a non-engaging direction with the tooth portion by contacting the claw member, and the ratchet type clutch is characterized in that.

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