Torque transmission device

Abstract

To achieve a torque transmission mechanism which can properly change torque to be transmitted while suppressing an increase in size of the mechanism.SOLUTION: A torque transmission device 10 performs torque transmission between a first member 11 and a second member 12. The torque transmission device includes: a differential gear mechanism 7 configured that the order of rotational speed is a first rotary element E1, a second rotary element E2 and a third rotary element E3; a first input member 1 fixed to the first member 11 and the first rotary element E1; a second input member 2 fixed to the second member 12 and the third rotary element E3; a reaction force support member 3 which is supported by a support member provided separately from a torque transmission path and is fixed to the second rotary element E2; and a differential limiting mechanism 5 which limits differential of the first input member 1 and the second input member 2 and can change the differential limiting state.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a torque transmission device that transmits torque between a first member and a second member.

Background Art

[0002] As an example of a device using such a torque transmission device, Japanese Patent Application Laid-Open No. 2007-162758 discloses a stabilizer mounted on a vehicle. This stabilizer is configured such that a cylindrical housing (10), a first stabilizer bar (14), a second stabilizer bar (15), a motor (20), and a speed reduction mechanism (G) are arranged coaxially (in the background art, the reference numerals in parentheses refer to those in the cited document). The rotation of the output shaft (23) of the motor (20) is reduced by the speed reduction mechanism (G), and the first stabilizer bar (14) is rotated with respect to the housing (10). In such a stabilizer, the torque of the motor (20) is amplified by the speed reduction mechanism (G) and converted into torsional torque in the stabilizer, changing the rigidity of the vehicle body with respect to the force (roll) that tilts the vehicle left and right.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the case of a torque transmission device having the above-described structure, there is a tendency for the motor to increase in size or the reduction ratio of the speed reduction mechanism to increase in order to obtain torque for changing the rigidity of the vehicle body. That is, in order to appropriately change the torque transmitted in the torque transmission device, the mechanism for transmitting the torque tends to increase in size.

[0005] Therefore, it is desired to realize a torque transmission mechanism that can appropriately change the transmitted torque while suppressing the increase in the size of the mechanism.

Means for Solving the Problems

[0006] The torque transmission device in view of the above is a torque transmission device that transmits torque between a first member and a second member, and includes a first rotating element, a second rotating element, and a third rotating element, and is configured such that the order of the rotational speeds of the first rotating element, the second rotating element, and the third rotating element is the same as the described order. A differential gear mechanism, a first input member fixed to the first member and fixed to the first rotating element, a second input member fixed to the second member and fixed to the third rotating element, and a reaction force support member supported by a support member provided separately from the torque transmission path and fixed to the second rotating element, and a differential limiting mechanism that limits the differential between the first input member and the second input member and can change the limited state of the differential.

[0007] According to this configuration, the first member and the second member are arranged via a differential gear mechanism, and the differential by the differential gear mechanism can be restricted by a differential restricting mechanism, so that the rigidity of the torque transmission structure between the first member and the second member can be changed. Specifically, by restricting the differential by the differential restricting mechanism, the rigidity of the torque transmission structure is changed to be increased, and by not restricting the differential by the differential restricting mechanism, the rigidity of the torque transmission structure can be changed to be decreased. When the differential is not restricted at all, in the case of reverse-phase input where the input to the first input member and the input to the second input member are in opposite directions, the first input member and the second input member relatively rotate in a free state, and the rigidity of the torque transmission structure becomes the lowest. In the case of in-phase input where the input to the first input member and the input to the second input member are in the same direction, the first input member and the second input member are difficult to relatively rotate, and the rigidity increases. Further, when the differential is completely restricted by the differential restricting mechanism, in either reverse-phase input or in-phase input, the first input member and the second input member cannot relatively rotate, and the rigidity of the torque transmission structure becomes the highest. Thus, according to this configuration, it is possible to realize a torque transmission mechanism that can appropriately change the transmitted torque while suppressing the enlargement of the mechanism.

[0008] Further features and advantages of the torque transmission device will become apparent from the following description of exemplary and non-limiting embodiments with reference to the drawings.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Mode for Carrying Out the Invention

[0010] Hereinafter, embodiments of the torque transmission device will be described with reference to the drawings. FIG. 1 is a schematic axial cross-sectional view showing a first example of the torque transmission device 10. FIG. 2 is a schematic cross-sectional view orthogonal to the axis showing a first example of the torque transmission device 10. FIG. 1 is a cross-sectional view taken along line I-I of FIG. 2, and FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1. As will be described later with reference to FIGS. 5 to 8, the torque transmission device 10 is used, for example, in a stabilizer device or a suspension device in a vehicle, and is connected to members (first member 11, second member 12) that transmit torque in the stabilizer device or the suspension device.

[0011] As shown in FIG. 1, the torque transmission device 10 is a device that transmits torque between the first member 11 and the second member 12. When the torque transmission device 10 is used in a vehicle, the first member 11 and the second member 12 are members on the vehicle side. The torque transmission device 10 includes a first input member 1 fixed to the first member 11, a second input member 2 fixed to the second member 12, a reaction force support member 3, a differential gear mechanism 7, and a differential limiting mechanism 5. The first input member 1, the second input member 2, the reaction force support member 3, the differential gear mechanism 7, and the differential limiting mechanism 5 are arranged coaxially (on the transmission axis X1). Hereinafter, the direction along the transmission axis X1 will be referred to as the axial direction L. The reaction force support member 3 is supported by a support member provided separately from the torque transmission path of the torque transmission device 10. When the torque transmission device 10 is used in a vehicle, the support member is the vehicle body 300 (see FIGS. 6 to 8, etc.). Note that the support member is not limited to a non-rotating member such as the vehicle body 300, and may be a rotating member (for example, a power transmission shaft) that rotates at the same speed as the rotation speed of the first member 11 and the rotation speed of the second member 12.

[0012] The differential gear mechanism 7 includes a first rotating element E1, a second rotating element E2, and a third rotating element E3. FIG. 3 shows the speed diagram of the differential gear mechanism 7. As shown in FIG. 3, the differential gear mechanism 7 is configured such that the order of the rotational speeds of the rotating elements is the order of the first rotating element E1, the second rotating element E2, and the third rotating element E3. The first rotating element E1 is connected to the first input member 1, the second rotating element E2 is connected to the reaction force support member 3, and the third rotating element E3 is connected to the second input member 2. That is, the first input member 1 is fixed to the first member 11 and is fixed to the first rotating element E1. The second input member 2 is fixed to the second member 12 and is fixed to the third rotating element E3. The reaction force support member 3 is supported by a support member provided separately from the torque transmission path and is fixed to the second rotating element E2. Here, the term "fixed" includes not only the form in which different members are integrally formed by welding, fastening, etc., but also the form in which they are integrally formed in the same member.

[0013] As shown in FIGS. 1 and 2, the planetary gear mechanism of the torque transmission device 10 of the first example is of a double pinion type, and the carrier CA rotatably supports the first pinion gear PG1 and the second pinion gear PG2. As shown in FIG. 2, the first pinion gear PG1 meshes with the sun gear SG and meshes with the second pinion gear PG2, and the second pinion gear PG2 meshes with the first pinion gear PG1 and meshes with the ring gear RG. As shown in FIGS. 1 and 3, in the torque transmission device 10 of the first example, the first rotating element E1 is the sun gear SG, the second rotating element E2 is the ring gear RG, and the third rotating element E3 is the carrier CA.

[0014] When rotational forces in different directions are input to the first input member 1 and the second input member 2, that is, in the case of so-called reverse-phase input, as shown in FIG. 3, the first input member 1 and the second input member 2 rotate relative to each other in opposite directions. That is, with the second rotating element E2 (ring gear RG) as a fulcrum, the first rotating element E1 (sun gear SG) and the third rotating element E3 (carrier CA) rotate in opposite directions to each other. That is, the first input member 1 and the second input member 2 can rotate relative to each other in a free state, and the rigidity of the torque transmission structure becomes the lowest. When rotational forces in the same direction are input to the first input member 1 and the second input member 2, that is, in the case of so-called in-phase input, the first input member 1 and the second input member 2 either do not rotate or rotate in the same direction (as will be described later for the movable mechanism 30, in this embodiment, the second rotating element E2 can rotate within a range where it rotates relative to the housing 4).

[0015] The differential limiting mechanism 5 is configured to limit the differential between the first input member 1 and the second input member 2 and to be able to change the limiting state of the differential between the first input member 1 and the second input member 2. In this embodiment, the differential limiting mechanism 5 includes an engaging device 50 that engages the first input member 1 and the second input member 2. In this embodiment, the engaging device 50 is configured to include at least a pair of friction engaging members 53. The pair of friction engaging members 53 includes a first friction engaging member 51 and a second friction engaging member 52. As shown in FIG. 1 (the same applies to FIG. 4), in this embodiment, a plurality of the first friction engaging members 51 and a plurality of the second friction engaging members 52 are provided respectively, and a plurality of pairs of friction engaging members 53 are provided to constitute the engaging device 50.

[0016] As described above, the differential limiting mechanism 5 is disposed on the transmission shaft X1. The opposing direction in which the respective friction engaging members (the first friction engaging member 51 and the second friction engaging member 52) oppose each other is the axial direction L. The engaging device 50 includes a pressing member 54 that presses the first friction engaging member 51 and the second friction engaging member 52 along the axial direction L, which is the opposing direction, and a driving device that drives the pressing member 54 in the opposing direction. In the present embodiment, a drive motor 60, which is an electric actuator, is exemplified as the driving device that drives the engaging device 50. In the present embodiment, the pressing member 54 is connected to the drive motor 60 via a speed reduction mechanism 65 that reduces the rotation of the drive motor 60 and a rotation-linear motion conversion mechanism 66 that converts the rotation of the drive motor 60 into linear motion along the opposing direction. Not limited to such a form, the electric actuator may be a solenoid, and the pressing member 54 may be connected to the movable iron core (plunger) of the solenoid.

[0017] Further, the driving device that drives the pressing member 54 in the opposing direction is not limited to an electric actuator, and may be a hydraulic circuit and a pump or the like that generates hydraulic pressure in the hydraulic circuit. Here, a friction engaging device is exemplified as the engaging device 50, but a meshing type engaging device may also be used. Even when the engaging device 50 is a meshing type engaging device, the driving device may be electric or hydraulic.

[0018] The differential limiting mechanism 5 of the present embodiment provided with a friction engaging device can change whether or not to limit the differential between the first input member 1 and the second input member 2, and can also change the degree of limitation (limiting state) when limiting the differential. When the differential is limited, the rigidity of the torque transmission structure increases. When the differential between the first input member 1 and the second input member 2 is completely limited, the first input member 1 and the second input member 2 are connected so as to rotate integrally. When the differential is completely limited by the differential limiting mechanism 5, neither the reverse-phase input nor the in-phase input allows the first input member 1 and the second input member 2 to rotate relative to each other, and the rigidity of the torque transmission structure becomes the highest.

[0019] As shown in FIG. 1, the first input member 1 is a shaft-like member at least a part of the axial direction L of which is disposed on the first axial side L1 which is one side in the axial direction L with respect to the second input member 2. The second input member 2 is a hook-shaped cylindrical member at least a part of the axial direction L of which is disposed on the second axial side L2 which is the side opposite to the first axial side L1 in the axial direction L with respect to the first input member 1, and the first input member 1 penetrates through the radially inner side. Therefore, in the radial direction view, at least a part of the first input member 1 and the second input member 2 overlap each other.

[0020] The second member 12 includes a small-diameter cylindrical portion 25 on the first axial side L1 and a large-diameter cylindrical portion 22 on the second axial side L2. A connecting member 21 for fixing the second input member 2 to the second member 12 is connected to the second axial side L2 of the large-diameter cylindrical portion 22. The connecting member 21 includes a bottom portion 21b that closes the opening on the second axial side L2 of the large-diameter cylindrical portion 22, and an axial engaging portion 21a that protrudes from the bottom portion 21b toward the second axial side L2. The second input member 2 is fixed to the second member 12 by connecting the engaging portion 21a and the second member 12.

[0021] On the first axial side L1 of the large-diameter cylindrical portion 22, a side wall portion 23 that extends radially inward so as to close the opening on the first axial side L1 of the large-diameter cylindrical portion 22, and a cylindrical connecting portion 24 that protrudes from the side wall portion 23 toward the first axial side L1 are provided. The side wall portion 23 is formed so as to cover the radially outer region of the opening on the first axial side L1 of the large-diameter cylindrical portion 22 in a state where the radially inner region is open. Then, a cylindrical connecting portion 24 is formed so as to protrude from the radially inner end portion of the side wall portion 23 toward the first axial side L1. The large-diameter cylindrical portion 22 and the small-diameter cylindrical portion 25 are connected by the engagement between the radially inner side of the connecting portion 24 and the radially outer side of the small-diameter cylindrical portion 25.

[0022] The first input member 1, which is a shaft-shaped member, is fixed to the first member 11 by being connected to the first member 11 on the first axial side L1. As described above, the first input member 1 is fixed to the sun gear SG of the planetary gear mechanism. In this embodiment, the sun gear SG is integrally formed on the first input member 1 by the same member as the first input member 1. Of course, the sun gear SG may be formed by a separate member from the first input member 1 and integrally formed with the first input member 1 by welding or fastening. As shown in FIG. 1, the first input member 1 is disposed inside the second input member 2 in the radial direction, and the first input member 1 and the second input member 2 are coaxially disposed on the transmission shaft X1. Further, an inner disposed portion 15, which is disposed in the inner space inside the large-diameter cylindrical portion 22 of the second input member 2, is connected to the end portion of the shaft-shaped portion of the first input member 1 on the second axial side L2. The inner disposed portion 15 is formed in a hook shape (a square C shape) with the opening facing the second axial side L2.

[0023] The first friction engaging member 51 of the engaging device 50 is disposed inside the inner disposed portion 15 in the radial direction. The first friction engaging member 51 is fixed to the inner disposed portion 15, and thereby the first friction engaging member 51 is fixed to the first input member 1. The inner disposed portion 15 can also be referred to as the first friction member support member. The second friction engaging member 52 is fixed to and supported by the second friction member support member 59. And the second friction member support member 59 is fixed to the inner wall of the large-diameter cylindrical portion 22, and thereby is fixed to the second input member 2. Thereby, the second friction engaging member 52 is fixed to the second input member 2. The engaging device 50 that engages the first friction engaging member 51 and the second friction engaging member 52 can connect the first input member 1 and the second input member 2 by engaging the large-diameter cylindrical portion 22 and the inner disposed portion 15.

[0024] That is, the torque transmission device 10 can be configured such that the second input member 2 includes a cylindrical portion (large-diameter cylindrical portion 22) formed in a cylindrical shape, the first input member 1 includes an inner arrangement portion 15 disposed on the transmission axis X1 coaxial with the cylindrical portion (large-diameter cylindrical portion 22) in the internal space of the cylindrical portion (large-diameter cylindrical portion 22), and the differential limiting mechanism 5 is disposed on the transmission axis X1 coaxial with the cylindrical portion (large-diameter cylindrical portion 22) in the internal space of the cylindrical portion (large-diameter cylindrical portion 22), and includes an engagement device 50 that engages the cylindrical portion (large-diameter cylindrical portion 22) and the inner arrangement portion 15.

[0025] As described above, the reaction force support member 3 fixed to the second rotating element E2 is supported by a support member (such as the vehicle body 300) provided separately from the torque transmission path of the torque transmission device 10. In the present embodiment, the reaction force support member 3 is supported by the support member via a movable mechanism 30 that allows relative rotation between the support member (such as the vehicle body 300) and the reaction force support member 3. As shown in FIG. 1, the movable mechanism 30 is provided between a housing 4, which is a fixed support member fixed to the support member, and the reaction force support member 3. In the torque transmission device 10, the movable mechanism 30 is provided between the housing 4 (fixed support member) and the reaction force support member 3, and is a mechanism that allows relative rotation between the housing 4 and the reaction force support member 3.

[0026] By allowing relative rotation between the housing 4 and the reaction force support member 3 by the movable mechanism 30, the relative phase between the housing 4 and the ring gear RG (second rotating element E2) fixed to the reaction force support member 3 changes. That is, in the speed diagram of FIG. 3, as indicated by the hollow arrow, the fulcrum changes.

[0027] The movable mechanism 30 includes a movable support mechanism 34 that supports the reaction force support member 3 so that the housing 4 and the reaction force support member 3 can rotate relative to each other, and a biasing mechanism 36 that biases the relative rotation phase between the housing 4 and the reaction force support member 3 to a predetermined reference phase. The differential gear mechanism 7, the movable mechanism 30, and the differential limiting mechanism 5 are disposed coaxially with the rotation axis (transmission axis X1) of the first rotating element E1. That is, in the present embodiment, the first input member 1, the second input member 2, the differential gear mechanism 7, the movable mechanism 30, and the differential limiting mechanism 5 are disposed coaxially.

[0028] The movable support mechanism 34 includes a helical spline 31 formed on the reaction force support member 3, a linear spline 33 formed on the housing 4 (fixed support member) along the axial direction L, and a movable member 32. The movable member 32 engages with both the helical spline 31 and the linear spline 33 to drive-connect the housing 4 and the reaction force support member 3. That is, the movable support mechanism 34 includes a movable member 32 that is movable in the axial direction L along the transmission axis X1, which is the rotation axis of the reaction force support member 3. The movable support mechanism 34 functions as a rotational-linear motion conversion mechanism that converts the moving direction between the rotational motion in which the movable member 32 is guided by the helical spline 31 and the linear motion in which the movable member 32 is guided by the linear spline 33. That is, the movable support mechanism 34 converts the relative rotation between the housing 4 (fixed support member) and the reaction force support member 3 into the movement of the movable member 32 in the axial direction L.

[0029] Further, the biasing mechanism 36 includes a biasing spring 35 that biases the movable member 32 in the axial direction L. In the present embodiment, a form in which the biasing spring 35 is a compression coil spring is illustrated, but it may be a tension coil spring. Also, in the present embodiment, the reference phase is the phase of the relative rotation between the housing 4 and the reaction force support member 3 in a state where the movable member 32 is biased most axially toward the first side L1 by the compression spring. That is, in the present embodiment, the phase corresponding to one end of the movement range of the movable member 32 (here, the end on the first side L1 in the axial direction) by the rotational-linear motion conversion mechanism is defined as the reference phase. However, it does not prevent setting the middle of the movement range of the movable member 32, instead of the end, as the reference phase. For example, in a case where the biasing spring 35 is a torsion coil spring that biases the reaction force support member 3 in the rotational direction, the middle of the movement range of the movable member 32 may be set as the reference phase.

[0030] Here, as the movable support mechanism 34, a rotational-linear motion conversion mechanism including a helical spline 31 formed on the reaction force support member 3, a linear spline 33 formed on the housing 4, and a movable member 32 is illustrated. However, the configuration is not limited to this, and for example, a configuration in which the reaction force support member 3 is rotatably supported with respect to the housing 4 by a bearing or the like may be used.

[0031] Next, with reference to FIG. 4, a second example of the torque transmission device 10 will be described. Regarding the configuration similar to that of the first example and the points that can be easily inferred from the above description of the first example, the description will be omitted as appropriate.

[0032] As shown in FIG. 4, the torque transmission device 10 of the second example also transmits torque between the first member 11 and the second member 12. When the torque transmission device 10 is used in a vehicle, the first member 11 and the second member 12 are members on the vehicle side. The torque transmission device 10 includes a first input member 1 fixed to the first member 11, a second input member 2 fixed to the second member 12, a reaction force support member 3, a differential gear mechanism 7, and a differential limiting mechanism 5. The first input member 1, the second input member 2, the reaction force support member 3, the differential gear mechanism 7, and the differential limiting mechanism 5 are arranged coaxially (on the transmission shaft X1). The reaction force support member 3 is supported by a support member provided separately from the torque transmission path of the torque transmission device 10. Similar to the first example, when the torque transmission device 10 of the second example is used in a vehicle, the support member is the vehicle body 300 (see FIGS. 6 to 8, etc.). Note that the support member is not limited to a non-rotating member such as the vehicle body 300, and may be a rotating member (for example, a power transmission shaft) that rotates at the same speed as the rotational speed of the first member 11 and the rotational speed of the second member 12.

[0033] The differential gear mechanism 7 includes a first rotating element E1, a second rotating element E2, and a third rotating element E3. Also in the second example, the first rotating element E1 is connected to the first input member 1, the second rotating element E2 is fixed to the reaction force support member 3, and the third rotating element E3 is connected to the second input member 2. That is, the first input member 1 is fixed to the first member 11 and is also fixed to the first rotating element E1. The second input member 2 is fixed to the second member 12 and is also fixed to the third rotating element E3. The reaction force support member 3 is supported by a support member provided separately from the torque transmission path and is fixed to the second rotating element E2.

[0034] As shown in Fig. 4, the planetary gear mechanism of the torque transmission device 10 of the second example includes two sun gears (first sun gear S1, second sun gear S2), and two pinion gears (first pinion gear PG1, second pinion gear PG2) with different diameters rotate integrally and are supported by a common carrier CA. The composite planetary gear mechanism (so-called 2KH type composite planetary gear mechanism). The first sun gear S1 meshes with the first pinion gear PG1, and the second pinion gear PG2 meshes with the second sun gear S2. This planetary gear mechanism is not provided with a ring gear. As shown in Figs. 3 and 4, in the torque transmission device 10 of the second example, the first rotating element E1 is the first sun gear S1, the second rotating element E2 is the second sun gear S2, and the third rotating element E3 is the carrier CA.

[0035] When rotational forces in different directions are input to the first input member 1 and the second input member 2, that is, in the case of so-called reverse-phase input, as shown in Fig. 3, the first input member 1 and the second input member 2 rotate relative to each other in opposite directions. That is, with the second rotating element E2 (second sun gear S2) as a fulcrum, the first rotating element E1 (first sun gear S1) and the third rotating element E3 (carrier CA) rotate in opposite directions to each other. That is, the first input member 1 and the second input member 2 can rotate relative to each other in a free state, and the rigidity of the torque transmission structure becomes the lowest. When rotational forces in the same direction are input to the first input member 1 and the second input member 2, that is, in the case of so-called in-phase input, the first input member 1 and the second input member 2 do not rotate or rotate in the same direction (as described above for the movable mechanism 30, in this embodiment, the second rotating element E2 can rotate within a range where it rotates relative to the housing 4).

[0036] The configurations of the differential limiting mechanism 5 and the movable mechanism 30 are as described above for the first example, so the description is omitted.

[0037] According to the torque transmission device 10 described above with reference to the first example and the second example, the first member 11 and the second member 12 are arranged via the differential gear mechanism 7, and the differential by the differential gear mechanism 7 can be restricted by the differential restricting mechanism 5, so that the rigidity of the torque transmission structure between the first member 11 and the second member 12 can be changed. Specifically, by restricting the differential by the differential restricting mechanism 5, the rigidity of the torque transmission structure can be changed to be higher, and by not restricting the differential by the differential restricting mechanism 5, the rigidity of the torque transmission structure can be changed to be lower. When the differential is not restricted at all, in the case of reverse-phase input where the input to the first input member 1 and the input to the second input member 2 are in opposite directions, the first input member 1 and the second input member 2 rotate relative to each other in a free state, and the rigidity of the torque transmission structure becomes the lowest. In the case of in-phase input where the input to the first input member 1 and the input to the second input member 2 are in the same direction, the first input member 1 and the second input member 2 are less likely to rotate relative to each other, and the rigidity becomes higher. Also, when the differential is completely restricted by the differential restricting mechanism 5, in either reverse-phase input or in-phase input, the first input member 1 and the second input member 2 cannot rotate relative to each other, and the rigidity of the torque transmission structure becomes the highest.

[0038] Such a torque transmission device 10 can be used in a stabilizer device or a suspension device in a vehicle. FIGS. 5 and 6 schematically show an example when the torque transmission device 10 is applied to the stabilizer device 100, and FIGS. 7 and 8 schematically show an example when the torque transmission device 10 is applied to the suspension device.

[0039] FIG. 5 is a schematic explanatory top view showing an example of attaching the torque transmission device 10 to a vehicle's stabilizer device 100. FIG. 6 is a schematic explanatory side view of an example of attaching the torque transmission device 10 as viewed from the VI-VI cross-section in FIG. 5. In FIGS. 5 and 6, 200, 201, 202, 203, 204, 210, and 220 are suspension arms that support the wheels W, respectively. 210 is a suspension arm that supports the first wheel (wheel W shown in FIG. 6), and 220 is a suspension arm that supports the second wheel. Xw is a wheel axis that is the rotation axis of the wheel W. The stabilizer device 100 includes a stabilizer arm that connects the suspension arm (210) of the first wheel and the suspension arm (220) of the second wheel. The torque transmission device 10 is disposed in the middle of the stabilizer arm so that the suspension arm (210) of the first wheel and the suspension arm (220) of the second wheel are connected via the torque transmission device 10.

[0040] As shown in FIG. 5, a first stabilizer arm 101 is connected to the suspension arm (210) of the first wheel, and a first input member 1 of the torque transmission device 10 is connected to the first stabilizer arm 101. Also, a second stabilizer arm 102 is connected to the suspension arm (220) of the second wheel, and a second input member 2 of the torque transmission device 10 is connected to the second stabilizer arm 102. The first stabilizer arm 101 corresponds to the first member 11, and the second stabilizer arm 102 corresponds to the second member 12.

[0041] FIG. 7 is a schematic explanatory top view showing an example of attaching the torque transmission device 10 to a suspension device of a vehicle. FIG. 8 is a schematic explanatory side view of an attachment example of the torque transmission device 10 as viewed from the VIII-VIII cross section in FIG. 7. In FIGS. 7 and 8, reference numerals 105 and 106 denote shaft members connected to a support member (vehicle body 300 including a suspension arm or the like) of the wheel W. The torque transmission device 10 is disposed in the middle of the shaft member such that a first shaft 105 connected to the support member of the first wheel and a second shaft 106 connected to the support member of the second wheel are connected via the torque transmission device 10.

[0042] As shown in FIG. 7, the first shaft 105 is connected to a support member (vehicle body 300) on the side of the first wheel (corresponding to the wheel W in FIG. 8), and the first input member 1 of the torque transmission device 10 is connected to the first shaft 105. Also, the second shaft 106 is connected to a support member (vehicle body 300) on the side of the second wheel, and the second input member 2 of the torque transmission device 10 is connected to the second shaft 106. The first shaft 105 corresponds to the first member 11, and the second shaft 106 corresponds to the second member 12.

[0043] When the torque transmission device 10 allows differential between the first input member 1 and the second input member 2, the ride comfort of the vehicle can be improved by absorbing the rotational difference between the first wheel and the second wheel. On the other hand, when the vehicle turns on a curve or the like, the roll rigidity of the vehicle can be increased by restricting the differential between the first input member 1 and the second input member 2, and the running stability of the vehicle during turning can be improved.

[0044] As described above, in the torque transmission device 10 of the present embodiment, since the differential limiting mechanism 5 includes a driving device, it is possible to adjust whether or not to limit the differential between the first input member 1 and the second input member 2 and the degree of limitation when limiting. Therefore, it is possible to appropriately switch between an operation mode that prioritizes ride comfort and an operation mode that prioritizes running stability.

[0045] The following describes other embodiments. Note that the configurations of the embodiments described below are not limited to being applied individually, and can be applied in combination with the configurations of other embodiments as long as there is no conflict.

[0046] (1) In the above, as the planetary gear mechanism constituting the differential gear mechanism 7, a double pinion type planetary gear mechanism (the torque transmission device 10 of the first example) and a 2KH type planetary gear mechanism (the torque transmission device 10 of the second example) were exemplified and described. However, the planetary gear mechanism is not limited to these configurations. For example, it may be a planetary gear mechanism having two sun gears with different diameters, a first pinion gear meshing with the large-diameter sun gear, a second pinion gear meshing with the small-diameter sun gear, a third pinion gear meshing with the second pinion gear and rotating integrally with the first pinion gear and having a smaller diameter than the first pinion gear, and a common carrier rotatably supporting the first pinion gear, the second pinion gear, and the third pinion gear. In the case of the planetary gear mechanism with this configuration, the large-diameter sun gear and the small-diameter sun gear become either the first rotating element or the third rotating element, respectively, and the carrier is the second rotating element.

[0047] (2) In the above, a planetary gear mechanism was exemplified and described as the differential gear mechanism 7. However, the differential gear mechanism 7 may be a bevel gear mechanism.

[0048] (3) In the above, a form in which the reaction force support member 3 is supported by a support member (such as the vehicle body 300, etc.) via the movable mechanism 30 was exemplified and described. However, a form in which the reaction force support member 3 is fixed to the support member without providing the movable mechanism 30 is not precluded.

[0049] The torque transmission device (10) described above is briefly summarized below.

[0050] The torque transmission device (10), in one aspect, is a torque transmission device (10) that transmits torque between a first member (11) and a second member (12), and includes a first rotating element (E1), a second rotating element (E2), and a third rotating element (E3). A differential gear mechanism (7) is configured such that the rotational speeds of the first rotating element (E1), the second rotating element (E2), and the third rotating element (E3) are in the order described; a first input member (1) fixed to the first member (11) and fixed to the first rotating element (E1); a second input member (2) fixed to the second member (12) and fixed to the third rotating element (E3); a reaction force support member (3) supported by a support member (300) provided separately from the torque transmission path and fixed to the second rotating element (E2); and a differential limiting mechanism (5) that limits the differential between the first input member (1) and the second input member (2) and can change the limiting state of the differential.

[0051] According to this configuration, the first member (11) and the second member (12) are arranged via a differential gear mechanism (7), and the differential by the differential gear mechanism (7) can be restricted by a differential restricting mechanism (5), so that the rigidity of the torque transmission structure between the first member (11) and the second member (12) can be changed. Specifically, by restricting the differential by the differential restricting mechanism (5), the rigidity of the torque transmission structure can be changed to be increased, and by not restricting the differential by the differential restricting mechanism (5), the rigidity of the torque transmission structure can be changed to be decreased. When the differential is not restricted at all, in the case of reverse-phase input where the input to the first input member (1) and the input to the second input member (2) are in opposite directions, the first input member (1) and the second input member (2) rotate relative to each other in a free state, and the rigidity of the torque transmission structure becomes the lowest. In the case of in-phase input where the input to the first input member (1) and the input to the second input member (2) are in the same direction, the first input member (1) and the second input member (2) are less likely to rotate relative to each other, and the rigidity becomes higher. Also, when the differential is completely restricted by the differential restricting mechanism (5), in either reverse-phase input or in-phase input, the first input member (1) and the second input member (2) cannot rotate relative to each other, and the rigidity of the torque transmission structure becomes the highest. Thus, according to this configuration, it is possible to realize a torque transmission mechanism that can appropriately change the transmitted torque while suppressing an increase in the size of the mechanism.

[0052] It is preferable that the torque transmission device (10) includes an engaging device (50) for engaging the first input member (1) and the second input member (2), and an electric actuator (60) for driving the engaging device (50) as the differential restricting mechanism (5).

[0053] According to this configuration, by changing the engaged state of the engaging device (50) by the actuator (60), it is possible to appropriately change whether or not to limit the differential between the first input member (1) and the second input member (2), and also to change the degree of limitation (limiting state) when limiting the differential. Further, in the case of an electric actuator (60), energy can be easily supplied to the actuator (60) by a power line or the like. Therefore, the torque transmission device (10) can be more easily mounted on a device or the like on which the torque transmission device (10) is to be mounted, as compared with the case where the engaging device (50) is driven by, for example, hydraulic pressure or the like.

[0054] Further, the torque transmission device (10) preferably includes an engaging device (50) in which the differential limiting mechanism (5) engages the first input member (1) and the second input member (2), and the engaging device (50) includes at least a pair of friction engaging members (53(51, 52)), a pressing member (54) that presses the pair of friction engaging members (53(51, 52)) in the facing direction (L) in which the respective friction engaging members (51, 52) face each other, and a driving device (60) that drives the pressing member (54) in the facing direction (L).

[0055] According to this configuration, by changing the engagement pressure of the engaging device (50), and by changing the engaged state of the engaging device (50) by the actuator (60), it is possible to appropriately change whether or not to limit the differential between the first input member (1) and the second input member (2), and also to change the degree of limitation (limiting state) when limiting the differential. Further, when limiting the differential, by changing the engagement pressure of the engaging device (50), the differential amount between the first input member (51) and the second input member (52) can be continuously changed. Therefore, the rigidity of the torque transmission structure between the first member (11) and the second member (12) can be continuously changed, and the torque transmission characteristics between the first member (11) and the second member (12) can also be continuously changed.

[0056] Further, the torque transmission device (10) The second input member (2) includes a cylindrical portion (22) formed in a cylindrical shape. The first input member (1) includes an inner arrangement portion (15) disposed coaxially (X1) with the cylindrical portion (22) in the inner space of the cylindrical portion (22). It is preferable that the differential limiting mechanism (5) is disposed coaxially (X1) with the cylindrical portion (22) in the inner space of the cylindrical portion (22) and includes an engaging device (50) that engages the cylindrical portion (22) and the inner arrangement portion (15).

[0057] According to this configuration, it is not necessary to separately provide a housing or the like of the engaging device (50), and the engaging device (50) that engages the inner arrangement portion (15) of the first input member (1) and the cylindrical portion (22) of the second input member (2) can be arranged in the inner space of the cylindrical portion (22) together with the inner arrangement portion (15), so that it is easy to reduce the size of the torque transmission device (10). Further, according to this configuration, since the engaging device (50) of the differential limiting mechanism (5) is configured to engage the cylindrical portion (22) and the inner arrangement portion (15) inside the cylindrical portion (22), it is easy to simplify the connection structure of the first input member (1) and the second input member (2) by the engaging device (50). Therefore, in this regard as well, it is easy to reduce the size of the torque transmission device (10).

[0058] Further, the torque transmission device (10) further includes a fixed support member (4) fixed to the support member (300), and a movable mechanism (30) provided between the fixed support member (4) and the reaction support member (3) and allowing relative rotation between the fixed support member (4) and the reaction support member (3). The movable mechanism (30) includes a movable support mechanism (34) that supports the reaction support member (3) so that the fixed support member (4) and the reaction support member (3) can rotate relative to each other, and a biasing mechanism (36) that biases the relative rotation phase between the fixed support member (4) and the reaction support member (3) to a predetermined reference phase. It is preferable to be provided.

[0059] According to this configuration, elastic rotational vibration of the reaction force support member (3) with respect to the support member (300) is allowed. That is, elastic rotational vibration of the first input member (1) and the second input member (2) with respect to the support member (300) is allowed. Therefore, a part of the vibration component of the torque transmitted through the first member (11) and the second member (12) can be absorbed. Also, the loads transmitted to the first input member (1) and the second input member (2) can be elastically supported.

[0060] Further, in the torque transmission device (10), the movable support mechanism (34) includes a movable member (32) movable in the axial direction (L) along the rotation axis (X1) of the reaction force support member (3), and a rotation-linear motion conversion mechanism that converts the relative rotation between the fixed support member (4) and the reaction force support member (3) into the movement of the movable member (32) in the axial direction (L). The biasing mechanism (36) includes a biasing spring (35) that biases the movable member (32) in the axial direction (L). It is preferable that the differential gear mechanism (7), the movable mechanism (30), and the differential limiting mechanism (5) are arranged coaxially with the rotation axis (X1) of the first rotating element (E1).

[0061] According to this configuration, the fixed support member (4) and the reaction force support member (3) can be made relatively rotatable, and the biasing spring can bias the relative rotation phase between the fixed support member (4) and the reaction force support member (3) to the reference phase. Also, according to this configuration, since the differential gear mechanism (7), the movable mechanism (30), and the differential limiting mechanism (5) are arranged coaxially with the rotation axis (X1) of the first rotating element (E1), it is easy to keep the radial dimension of the torque transmission device (10) small.

Explanation of Reference Numerals

[0062] 1: First input member, 2: Second input member, 3: Reaction support member, 4: Housing (fixed support member), 5: Differential limiting mechanism, 7: Differential gear mechanism, 10: Torque transmission device, 11: First member, 12: Second member, 15: Inner arrangement part, 22: Large-diameter cylindrical part (cylindrical part), 30: Movable mechanism, 32: Movable member, 34: Movable support mechanism, 35: Biasing spring, 36: Biasing mechanism, 50: Engagement device, 51: First friction engagement member (one of each of the pair of friction engagement members), 52: Second friction engagement member (the other of each of the pair of friction engagement members), 53: Pair of friction engagement members, 54: Pressing member, 60: Driving motor (driving device, electric actuator), 66: Rotary-linear motion conversion mechanism, 300: Vehicle body (support member provided separately from the torque transmission path), E1: First rotating element, E2: Second rotating element, E3: Third rotating element, L: Axial direction, X1: Transmission shaft (rotation axis of the reaction support member, rotation axis of the first rotating element)

Claims

1. A torque transmission device that transmits torque between a first member and a second member, comprising a first rotating element, a second rotating element, and a third rotating element, and a differential gear mechanism configured such that the rotational speeds of the first rotating element, the second rotating element, and the third rotating element are in the order described, a first input member fixed to the first member and fixed to the first rotating element, a second input member fixed to the second member and fixed to the third rotating element, a reaction force support member supported by a support member provided separately from the torque transmission path and fixed to the second rotating element, and a differential limiting mechanism that limits the differential between the first input member and the second input member and can change the limiting state of the differential. A torque transmission device comprising the differential limiting mechanism.

2. The differential limiting mechanism includes an engaging device that engages the first input member and the second input member, and an electric actuator that drives the engaging device. The torque transmission device according to claim 1.

3. The differential limiting mechanism includes an engaging device that engages the first input member and the second input member, wherein the engaging device includes at least a pair of friction engaging members, a pressing member that presses the pair of friction engaging members in a facing direction, which is the direction in which the respective friction engaging members face each other, and a driving device that drives the pressing member in the facing direction. The torque transmission device according to claim 1.

4. The second input member includes a cylindrical portion formed in a cylindrical shape, the first input member includes an inner disposed portion disposed coaxially with the cylindrical portion in the internal space of the cylindrical portion, and the differential limiting mechanism includes an engaging device disposed coaxially with the cylindrical portion in the internal space of the cylindrical portion and engaging the cylindrical portion and the inner disposed portion. The torque transmission device according to claim 1.

5. further comprising a fixed support member fixed to the support member, and a movable mechanism provided between the fixed support member and the reaction force support member and allowing relative rotation between the fixed support member and the reaction force support member, wherein the movable mechanism includes a movable support mechanism that supports the reaction force support member so that the fixed support member and the reaction force support member can rotate relative to each other, and a biasing mechanism that biases the relative rotation phase between the fixed support member and the reaction force support member to a predetermined reference phase. The torque transmission device according to any one of claims 1 to 4.

6. The movable support mechanism includes a movable member that is movable in an axial direction along the rotation axis of the reaction force support member, and includes a rotary-linear motion conversion mechanism that converts the relative rotation between the fixed support member and the reaction force support member into the axial motion of the movable member. The biasing mechanism includes a biasing spring that biases the movable member in the axial direction. The torque transmission device according to claim 5, wherein the differential gear mechanism, the movable mechanism, and the differential limiting mechanism are arranged coaxially with the rotation axis of the first rotating element.

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