JP5146742B2 - Differential - Google Patents

Description

  The present invention relates to a differential device that distributes torque of an input shaft to a pair of output shafts while allowing a differential between both output shafts in a vehicle.

  Conventionally, differential gears, LSD (differential gears with differential limiting function), left and right wheels have been used as differential gears to distribute the input shaft torque to a pair of output shafts while allowing the differential between the two output shafts. Various devices such as a left / right driving force distribution device that distributes driving force to the left and right are known. These differential devices are constituted by a combination of involute gears represented by a planetary mechanism.

  For example, Japanese Unexamined Patent Application Publication No. 2006-112474 (Patent Document 1) discloses a differential device that combines a differential mechanism with a plurality of sun gears, a plurality of planetary gears, a plurality of carriers, a sub-power source, and the like. Yes. In the case of this Patent Document 1, the first sun gear and the second sun gear with which the first planetary gear is meshed are set to have slightly different number of teeth, or each sun gear and each planetary gear are externally geared. It is said that a differential device that can easily ensure accuracy can be obtained without increasing the size of the motor and complicating the structure.

However, even in the case of the differential device disclosed in Patent Document 1, a planetary mechanism in which a plurality of sun gears, a plurality of planetary gears, and the like are combined is employed, so that a large number of involute gears are used. In addition, when more special functions are added or combined, more functional members such as gears are required. As a result, the physique is enlarged and the structure is complicated. .
JP 2006-112474 A

  The present invention has been made in view of the above circumstances, and provides a novel differential device that can realize a differential gear, an LSD, and a left / right driving force distribution device that can be miniaturized with a simple configuration. It is a problem to be solved.

  Hereinafter, each means suitable for solving the above-described problems will be described while adding effects and the like as necessary.

[Means 1] A differential device of means 1 includes an input shaft that rotates in response to a torque of a driving source of a vehicle, and a pair of output shafts. A differential device that distributes while allowing the differential between the shafts,
A first rotating element; a second rotating element that can rotate at a different rotational speed from the first rotating element as the first rotating element rotates; and the rotating speeds of the first rotating element and the second rotating element Comprising a first and a second transmission consisting of a third rotating element whose rotational speed is determined according to
The first rotating elements of the first and second transmissions are coupled to each other so as not to rotate relative to each other to form a ring plate, and a first rotating body connected to the input shaft,
Second and third rotating bodies each comprising the second rotating element and connected to each of the output shafts;
The first rotating body and the second or third rotating body are coupled so as to be differentially rotatable, and the first rotating body is rotatable about an axis inclined with respect to the first axis of the first to third rotating bodies. And a second differential rotating member,
A fourth rotating body in which the third rotating elements are coupled so as not to rotate relative to each other, and rotatably support the inner circumference or the outer circumference of the first and second differential rotating members;
A transmission mechanism with
Gears are formed on both end faces of the first rotating body,
A gear is formed on one end surface of the second and third rotating bodies,
Gears that can mesh with the gears of the first to third rotating bodies are formed on both end faces of the first and second differential rotating members,
The number of teeth of each gear is such that when the fourth rotating body is fixed, the second rotating body advances by a difference in the number of teeth from the first rotating body with respect to one rotation of the first rotating body. The third rotating body is set to rotate with a delay of a difference in the number of teeth from the first rotating body .

The differential device of the means 1 includes first and second transmissions including a first rotation element, a second rotation element, and a third rotation element, and the first to third rotation elements and the second transmission of the first transmission . By combining the first to third rotating elements of the transmission in a predetermined state as described above, a transmission mechanism including the first to fourth rotating bodies and the differential rotating member is constructed. In the means 1, the first rotating body is connected to the input shaft, and the second and third rotating bodies are connected to the output shafts.

Thereby, if the 4th rotary body is made into the free state, a differential gear will be realized. That is, in this case, the gear ratio between the first rotating body connected to the input shaft and the second rotating body connected to one output shaft, and the first rotating body connected to the input shaft and the other output By appropriately setting the gear ratio with the third rotating body connected to the shaft, the third rotating body is configured to rotate in the reverse direction when the second rotating body rotates. Moreover, it is comprised so that the whole apparatus may rotate by rotating a 1st rotary body.

Moreover , LSD is implement | achieved if regulation means, such as a clutch which interrupts | transmits torque transmission between a 4th rotary body and one output shaft, is provided. That is, in this case, the rotational difference between the second rotating body and the third rotating body can be eliminated by rotationally driving the fourth rotating body with the clutch engaged. This facilitates escape when one wheel of the vehicle is derailed or fitted into a mud.

Further , if the fourth rotating body is connected to a control shaft capable of controlling the rotation speed so as to be able to transmit the rotation, a vehicle left-right driving force distribution device is realized. That is, in this case, the driving force transmitted to the left and right wheels via the second and third rotating bodies is appropriately distributed by driving the control shaft and controlling the rotation of the fourth rotating body. Can do.

  Therefore, according to the means 1, it is possible to realize a differential gear, an LSD, and a left / right driving force distribution device that can be reduced in size with a simple configuration.

Further, in the first means, the first rotating body and the second or third rotating body are connected so as to be differentially rotatable, and can be rotated about an axis inclined with respect to the first axis of the first to third rotating bodies. Since the first and second differential rotating members are provided, the gear ratio between the first rotating body and the second rotating body and the first rotating body and the third rotation are determined by the first and second differential rotating members. The gear ratio with the body can be easily set to satisfy a predetermined condition.

[Means 2 ] The differential device of the means 2 is the differential device described in the means 1, characterized in that the speed change mechanism is a differential gear.

According to the means 2 , since the speed change mechanism includes the first to fourth rotating bodies, the function required for the differential gear can be easily satisfied with a simple configuration.

[Means 3 ] The differential device of the means 3 is the differential device according to the means 1 or 2 , wherein the fourth rotating body is connected to a control shaft capable of controlling a rotation speed so as to transmit the rotation. It is a feature.

According to the means 3 , the LSD and the left / right driving force distribution device can be easily realized.

[Means 4 ] The differential device of the means 4 is the differential device according to any one of the means 1 to 3 , wherein the torque transmission between the fourth rotating body and one of the output shafts is interrupted. It is characterized by having means.

According to the means 4 , the LSD and the left / right driving force distribution device can be easily realized.

[Means 5 ] The differential device of the means 5 is characterized in that the regulating means in the differential device described in the means 4 is a clutch device.

According to the means 5 , the restricting means of the means 4 can be easily realized with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Embodiment 1
FIG. 1 is a cross-sectional view of the differential device according to the first embodiment along the axial direction. The differential device of Embodiment 1 employs the above-described single gear (bearing reducer) to realize a differential gear. The differential device includes a first rotating element, a second rotating element that can rotate at a rotation speed different from the first rotating element as the first rotating element rotates, and the first rotating element and the second rotating element. First and second transmissions each including a third rotation element whose rotation speed is determined according to the rotation speed are provided.

  As shown in FIG. 1, the differential device includes a first rotating body 10, a second rotating body 20, a third rotating body 30, a fourth rotating body 40, rolling elements 45 and 46, and a first rotating body. A differential rotation member 50 and a second differential rotation member 60 are provided.

  The first rotating body 10 is formed by connecting the first rotating elements of the first transmission and the second transmission so that they cannot rotate relative to each other, and is formed in a ring plate shape. The first rotating body 10 is integrally held by a carrier (not shown). And the carrier is connected with the propeller shaft (input shaft) of the vehicle which is not illustrated. Thereby, the 1st rotary body 10 receives the torque from the drive source of a vehicle via a propeller shaft, and can be rotated to the surroundings of the axis line L1 with a carrier. End face gears 11 and 12 are respectively provided on the inner peripheral sides of both end faces of the first rotating body 10. The end surface gears 11 and 12 are uneven in the circumferential direction, and each unevenness is formed to extend radially. The number of teeth of the end face gear 11 is 50, and the number of teeth of the end face gear 12 is 49.

  The second rotating body 20 is composed of a second rotating element of the first transmission, and includes a cylindrical portion 21 having a bottomed cylindrical shape and a shaft portion 22 that is coaxially connected to the bottom outer surface of the cylindrical portion 21. Become. The second rotating body 20 has the opening side end surface (the right end surface in FIG. 1) of the cylindrical portion 21 facing the one end surface (the left end surface in FIG. 1) of the first rotating body 10 with a predetermined distance therebetween. The carrier is rotatably supported. The rotation axis of the second rotator 20 is coaxial with the rotation axis (axis line L1) of the first rotator 10. As for the 2nd rotary body 20, the axial part 22 is connected with one wheel (one output shaft) which is not shown in figure in both right and left wheels. An end face gear 23 is provided on the opening-side end face of the cylindrical portion 21 that faces the one end face of the first rotating body 10. The end face gear 23 is uneven in the circumferential direction, and each unevenness is formed to extend radially. The outer diameter dimension of the end face gear 23 is slightly smaller than the outer diameter dimension of the end face gear 11 of the first rotating body 10. The number of teeth of the end face gear 23 is 49.

  The third rotating body 30 is composed of the second rotating element of the second transmission, and is formed in the same manner as the second rotating body 20. The third rotating body 30 includes a cylindrical portion 31 having a bottomed cylindrical shape, and a shaft portion 32 that is coaxially connected to the outer surface of the bottom portion of the cylindrical portion 31.

  The third rotating body 30 is configured so that the opening-side end face (left end face in FIG. 1) of the cylindrical portion 31 faces the other end face (right end face in FIG. 1) of the first rotating body 10 with a predetermined distance therebetween. The carrier is rotatably supported. The rotation axis of the third rotating body 30 is coaxial with the axis L1. As for this 3rd rotary body 30, the axial part 32 is connected with the other wheel (other output shaft) which is not shown in figure in both right and left wheels. An end surface gear 33 is provided on the opening side end surface of the cylindrical portion 31 facing the other end surface of the first rotating body 10. As with the cross-sectional gear 23, the end surface gear 33 is uneven in the circumferential direction, and each unevenness is formed to extend radially. The outer diameter dimension of the end face gear 33 is slightly smaller than the outer diameter dimension of the end face gear 12 of the first rotating body 10.

  The fourth rotating body 40 is formed by coupling the third rotating elements of the first transmission and the second transmission so that they cannot rotate relative to each other. The fourth rotating body 40 is provided integrally with the shaft portion 41 and both ends of the shaft portion 41. And circular swash plates 42 and 43. The shaft portion 41 is disposed coaxially with the first rotating body 10 on the inner peripheral side of the first rotating body 10. One swash plate 42 is positioned between the first rotating body 10 and the second rotating body 20 in the direction of the axis L1, and the central axis thereof is a predetermined angle toward the first rotating body 10 with respect to the axis L1. It is provided in a tilted state. On the outer peripheral surface of one swash plate 42, rolling surfaces 42 a having an arc concave cross section on which rolling elements 45 made of a plurality of spheres roll are formed in two rows over the entire circumference.

  The other swash plate 43 is positioned between the first rotating body 10 and the third rotating body 30 in the direction of the axis L1, and the central axis thereof is a predetermined angle toward the first rotating body 10 with respect to the axis L1. It is provided in a tilted state. The inclination angles of both swash plates 42 and 43 are the same. On the outer peripheral surface of the other swash plate 43, two rows of rolling surfaces 43a having an arc concave cross section on which rolling elements 46 made of a plurality of spheres roll are formed over the entire circumference.

  The first differential rotation member 50 is formed in a cylindrical shape. On the inner peripheral surface of the first differential rotating member 50, two rows of rolling surfaces 51 having an arc concave cross section on which the rolling elements 45 roll are formed over the entire circumference. The first differential rotation member 50 is fitted on the outer periphery of one swash plate 42 of the fourth rolling body 40 via a rolling element 45 so as to be relatively rotatable. The first differential rotation member 50 is provided so as to be coaxial with the central axis of one swash plate 42. End surface gears 52 and 53 are provided on both end surfaces of the first differential rotation member 50 so as to have a concavo-convex shape in the circumferential direction, and each concavo-convex shape extends radially.

  The end face gear 52 provided on the end face on the first rotating body 10 faces the end face gear 11 provided on the first rotating body 10 and meshes with the end face gear 11 in a part in the circumferential direction. The number of teeth of the end face gear 52 is 50. On the other hand, the end face gear 53 provided on the end face on the second rotating body 20 faces the end face gear 23 provided on the second rotating body 20 and meshes with the end face gear 23 in a part in the circumferential direction. The number of teeth of the end face gear 53 is 50.

  The first differential rotation member 50 provided in this way is composed of the end surface gear 52 and the end surface gear 11 and the end surface gear 53 and the end surface gear 23 that mesh with each other. Only the number of teeth is set to 49, which is one less than the other, thereby connecting the first rotating body 10 and the second rotating body 20 so as to be differentially rotatable. In addition, since the 4th rotary body 40 which is supporting the 1st differential rotation member 50 with one swash plate 42 is enabled to rotate relatively via the rolling element 45, Not constrained by rotational movement. In other words, the fourth rotating body 40 is not restricted by the rotation operations of the first rotating body 10 and the second rotating body.

  Similar to the first differential rotation member 50, the second differential rotation member 60 is formed in a cylindrical shape. On the inner peripheral surface of the second differential rotating member 60, two rows of rolling surfaces 61 having an arc concave cross section on which the rolling elements 46 roll are formed over the entire circumference. The second differential rotation member 60 is fitted on the outer periphery of the other swash plate 43 of the fourth rolling body 40 via a rolling element 46 so as to be relatively rotatable. The second differential rotation member 60 is provided coaxially with the central axis of the other swash plate 43. End surface gears 62 and 63 are provided on both end surfaces of the second differential rotation member 60 so as to have a concavo-convex shape in the circumferential direction, and each concavo-convex shape extends radially.

The end face gear 62 provided on the end face on the first rotating body 10 faces the end face gear 12 provided on the first rotating body 10 and meshes with the end face gear 12 in a part in the circumferential direction. The number of teeth of the end face gear 62 is 50 . On the other hand, the end face gear 63 provided on the end face on the third rotating body 30 side faces the end face gear 33 provided on the third rotating body 30 and meshes with the end face gear 33 in a part in the circumferential direction. The number of teeth of the end face gear 63 is 50.

  The second differential rotation member 60 provided in this way is composed of the end face gear 62 and the end face gear 12 and the end face gear 63 and the end face gear 33 that are meshed with each other, of the end face gear 12 provided on the first rotating body 10. Only the number of teeth is set to 49, which is one less than the other, thereby connecting the first rotating body 10 and the third rotating body 30 so as to be differentially rotatable. In addition, since the 4th rotary body 40 which is supporting the 2nd differential rotation member 60 with the other swash plate 43 is enabled relative rotation via the rolling element 46, the 2nd differential rotation member 60 of FIG. Not constrained by rotational movement. In other words, the fourth rotating body 40 is not restricted by the rotation operations of the first rotating body 10 and the third rotating body 30. Therefore, the fourth rotating body 40 is in a free state with respect to the first to third rotating bodies 10, 20, 30 and the first and second differential rotating members 50, 60.

  The operation of the differential device configured as a differential gear as described above will be described. In the differential device of the present embodiment, the fourth rotator 40 is rotatable relative to the first to third rotators 10, 20, and 30 about the axis L1. Therefore, the first and second differential rotating members 50 and 60 can rotate relative to the first to third rotating bodies 10, 20, and 30 around the axis L <b> 1. That is, the first and second differential rotating members 50 and 60 can swing with respect to the first to third rotating bodies 10, 20, and 30.

  Here, for ease of explanation, a case where the first rotating body 10 makes one revolution by torque input from the input shaft will be described. When the first rotating body 10 makes one rotation, on the second rotating body 20 side, the meshing position between the teeth of the end surface gear 11 of the first rotating body 10 and the teeth of the end surface gear 52 of the first differential rotating member 50 is It shifts in the circumferential direction. Similarly, the meshing position between the teeth of the end face gear 53 of the first differential rotating member 50 and the teeth of the end face gear 23 of the second rotating body 20 is shifted in the circumferential direction.

In the present embodiment, since the number of teeth (50) of the end surface gear 11 of the first rotating body 10 and the number of teeth (50) of the end surface gear 52 of the first differential rotating member 50 are the same, the first differential rotating member 50 does not rotate with respect to the first rotating body 10. On the other hand, the number of teeth of the end face gear 23 of the second rotating body 20 is 49, and is set to be different from the number of teeth (50) of the end face gear 53 of the first differential rotating member 50. Therefore, when the 4th rotary body 40 is fixed, the 2nd rotary body 20 advances and rotates with respect to the 1st rotary body 10 by the difference of the number of teeth. That is, when the first rotating body 10 is rotated once, the second rotating body 20 rotates leads by one revolution of 49 minutes for the first rotor 10.

  On the third rotating body 30 side of the first rotating body 10, when the first rotating body 10 makes one rotation, the teeth of the end face gear 12 of the first rotating body 10 and the end face gear 62 of the second differential rotating member 60. The meshing position of the tooth and the meshing position of the tooth of the end face gear 63 of the second differential rotating member 60 and the tooth of the end face gear 33 of the third rotating body 30 are also shifted in the circumferential direction as described above.

In this case, the number of teeth of the end surface gear 12 of the first rotating body 10 is set to 49, and is set to be different from the number of teeth (50) of the end surface gear 62 of the second differential rotating member 60. For this reason, when the fourth rotating body 40 is fixed, the second differential rotating member 60 rotates with respect to the first rotating body 10 with a difference in the number of teeth. That is, when the first rotating body 10 makes one rotation, the second differential rotating member 60 rotates with a delay of 1/50. On the other hand, since the number of teeth (50) of the end face gear 63 of the second differential rotating member 60 and the number of teeth (50) of the end face gear 33 of the third rotating body 30 are the same, the third rotating body 30 has the second difference. The rotating member 60 does not rotate. Therefore, when the first rotating body 10 makes one rotation, the third rotating body 30 rotates with a delay of 1/50 with respect to the first rotating body 10. As a result, the second rotator 20 and the third rotator 30 rotate in the opposite directions to generate a rotation difference. That is, in the differential device of this embodiment, the torque input from the input shaft to the first rotator 10 is the second rotator 20 connected to one output shaft and the third rotator connected to the other output shaft. The rotating body 30 is distributed while allowing a differential.

  As described above, according to the differential device of the present embodiment, the transmission mechanism including the first to fourth rotating bodies 10, 20, 30, and 40 configured as described above is employed. Therefore, a differential gear that can be reduced in size with a simple configuration can be realized.

  In the present embodiment, the first and second differential rotating members 50 and 60 that connect the first rotating body 10 and the second or third rotating bodies 20 and 30 so as to be differentially rotatable are provided. The reduction ratio between the first rotator 10 and the second rotator 20 and the reduction ratio between the first rotator 10 and the third rotator 30 can be easily set to satisfy a predetermined condition.

  Further, in the present embodiment, since a single gear (bearing speed reducer) is employed, a differential gear with a relatively small speed reduction can be advantageously realized.

[Reference example]
2 is a cross-sectional view along the axial direction of the differential according to the reference example , FIG. 3 is a schematic view of the harmonic gear, and (a) is a view seen from the left direction of (b). b) is a sectional view in the axial direction, and (c) is a view as seen from the right direction of (b). In FIG. 3, reference numerals corresponding to the configuration of FIG. 2 are given.

The differential device of the reference example realizes a differential gear by employing the above-described harmonic gear instead of the single gear (bearing speed reducer) employed in the first embodiment. In the reference example , the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 2, the differential device includes a first rotating body 110, a second rotating body 120, a third rotating body 130, a fourth rotating body 140, a rolling element 145, an outer ring 150, And a differential rotation member 160.

  The first rotating body 110 is formed with an inner peripheral surface gear 111 in place of the end surface gears 11 and 12 in the first rotating body 10 of the first embodiment. That is, the first rotating body 110 constitutes a stator gear of a harmonic gear. The other configuration is substantially the same as the first rotating body 10 of the first embodiment.

  The second rotating body 120 includes an inner peripheral surface gear 121 in place of the end surface gear 23 in the second rotating body 20 of the first embodiment. This 2nd rotary body 120 comprises the driven gear of a harmonic gear. The other configuration is substantially the same as the second rotating body 20 of the first embodiment.

  Moreover, the 3rd rotary body 130 is replaced with the end surface gear 33 in the 3rd rotary body 30 of Embodiment 1, and the internal peripheral surface gear 131 is formed. The third rotating body 130 constitutes a driven gear of a harmonic gear. The other configuration is substantially the same as the third rotating body 30 of the first embodiment.

  The 4th rotary body 140 is comprised by the cylindrical body whose outer peripheral surface is elliptical. Two rows of rolling surfaces 141 on which the rolling elements 145 roll are formed on the outer peripheral surface of the fourth rotating body 14 over the entire circumference. The rolling element 145 includes a plurality of spheres and rolls on the rolling surface 141.

  The outer ring 150 is formed of an elliptical cylinder corresponding to the outer peripheral surface of the fourth rotating body 140. Two rows of rolling surfaces 151 on which the rolling elements 145 roll are formed on the inner circumferential surface of the outer ring 150 over the entire circumference. That is, the 4th rotary body 140, the rolling element 145, and the outer ring | wheel 150 comprise the wave generator of a harmonic gear.

  The differential rotating member 160 is formed of a thin cylindrical body having a gear formed on the outer peripheral surface. The differential rotating member 160 is press-fitted and fixed to the outer peripheral side of the outer ring 150. That is, the differential rotating member 160 is rotatably supported by the fourth rotating body 140. The outer peripheral surface gear of the differential rotating member 160 is engaged with the inner peripheral surface gear 111 of the first rotating body 110 and the inner peripheral surface gears 121 and 131 of the second and third rotating bodies 120 and 130. That is, the differential rotating member 160 constitutes a flex spline of a harmonic gear.

Even when configured as described above, substantially the same operation as the differential gear as in the first embodiment is performed. Therefore, this reference example also has the same effect as that of the first embodiment.

[Embodiment 2 ]
FIG. 4 is a cross-sectional view along the axial direction of the differential according to the second embodiment. The differential device of the second embodiment employs the single gear (bearing speed reducer) employed in the first embodiment to realize a left / right driving force distribution device for a vehicle. As shown in FIG. 4, in the differential device of the second embodiment, the fourth rotating bodies 240 </ b> A and 240 </ b> B are divided into two and the first and second differences as compared with the differential device of the first embodiment. It is different in that it is arranged on the outer peripheral side of the dynamic rotating members 50 and 60. In addition, a control shaft 270 capable of controlling the rotation speed of the fourth rotating bodies 240A and 240B is connected to the fourth rotating bodies 240A and 240B divided into two parts via the gear train 280 so as to transmit the rotation. Thus, the third rotation elements of both transmissions are different from each other in that they are coupled so as not to rotate relative to each other .

The other configuration of the differential device of the second embodiment is substantially the same as that of the first embodiment. Therefore, the same components are denoted by the same reference numerals, detailed description thereof is omitted, and different points are hereinafter described. Will be explained.

  The fourth rotating bodies 240A and 250B of the present embodiment are formed in a thick cylindrical shape having an inner diameter larger than the outer diameters of the first and second differential rotating members 50 and 60. The fourth rotating bodies 240A and 250B are arranged on the outer peripheral side of the first and second differential rotating members 50 and 60 with the first rotating body 10 interposed therebetween and facing the axis L1 direction.

On the inner peripheral surface of one fourth rotating body 240A, two rows of rolling surfaces 242a on which the rolling elements 45 roll are formed over the entire circumference. On the other hand, in Embodiment 1, the rolling surface 51 of the rolling element 45 is provided on the inner peripheral surface of the first differential rotating member 50. However, in Embodiment 2 , the rolling surface 245 of the rolling element 45 is the first. 1 is provided on the outer peripheral surface of the differential rotation member 50. The fourth rotating body 240A is disposed so as to be coaxial with the central axis of the first differential rotating member 50 inclined by a predetermined angle with respect to the axis L1. Accordingly, the fourth rotating body 240A can rotate relative to the first differential rotating member 50 via the rolling element 45. An outer peripheral surface gear 243A is formed on the outer peripheral surface of the fourth rotating body 240A.

In addition, two rows of rolling surfaces 243a on which the rolling elements 46 roll are formed over the entire circumference on the inner circumferential surface of the other fourth rotating body 240B. On the other hand, in Embodiment 1, the rolling surface 61 of the rolling element 46 is provided on the inner peripheral surface of the second differential rotating member 60, but in Embodiment 2 , the rolling surface 246 of the rolling element 46 is the second. It is provided on the outer peripheral surface of the differential rotating member 60. The fourth rotating body 240B is disposed so as to be coaxial with the central axis of the second differential rotating member 60 inclined by a predetermined angle with respect to the axis L1. As a result, the fourth rotating body 240 </ b> B can rotate relative to the second differential rotating member 60 via the rolling element 46. An outer peripheral surface gear 243B is formed on the outer peripheral surface of the fourth rotating body 240B.

  A control shaft 270 that is rotationally driven and controlled by a motor (not shown) is disposed on the outer peripheral side of the fourth rotating bodies 240A and 240B. The control shaft 270 is provided with a gear train 280 including a first gear 281 that meshes with the outer peripheral surface gear 243A of the fourth rotating body 240A and a second gear 282 that meshes with the outer peripheral surface gear 243B of the fourth rotating body 240B. .

  The differential device of the present embodiment configured as described above can simultaneously control the rotation speeds of both the fourth rotating bodies 240A and 240B by controlling the rotational drive of the control shaft 270 with a motor. Thereby, the left-right driving force distribution device for vehicles can be easily realized.

  In particular, the differential device of the present embodiment can effectively use one of the four rotating bodies, which is advantageous in simplifying the structure and reducing the size.

[Embodiment 3 ]
FIG. 5 is a cross-sectional view along the axial direction of the differential according to the third embodiment. The differential device of the third embodiment employs the single gear (bearing speed reducer) employed in the first and second embodiments to realize an LSD (differential gear with a differential limiting function).

As shown in FIG. 5, the differential device according to the third embodiment includes a first rotating body 310, a second rotating body 320, a third rotating body 330, a fourth rotating body 340, a yoke 345, and an inner ring 350. , 351, rolling elements 355 and 356, a first differential rotation member 360, a second differential rotation member 370, a clutch unit 380, and an electromagnet 390.

  The first rotating body 310 includes a ring plate 311, a first cylindrical member 312, and a second cylindrical member 313. The first cylindrical member 312 includes a large-diameter portion 312a, a ring-shaped outward flange portion 312b formed at one end of the large-diameter portion 312a, and a ring-shaped inward flange formed at the other end of the large-diameter portion 312a. The portion 312c and a small diameter portion 312d extending outward in the axial direction from the inner peripheral end of the inward flange portion 312c. The second cylindrical member 313 includes a large-diameter portion 313a, a ring-shaped outward flange portion 313b formed at one end of the large-diameter portion 313a, and a ring-shaped inner portion formed at the other end of the large-diameter portion 313a. It consists of a facing flange portion 313c and a small diameter portion 313d extending outward in the axial direction from the inner peripheral end of the inward flange portion 313c.

  The large diameter portion 312a and the large diameter portion 313a have the same diameter, and the outward flange portion 312b and the outward flange portion 313b are formed in the same shape and size. The first cylindrical member 312 and the second cylindrical member 313 are integrally connected with the outward flange portions 312b and 313b sandwiching the ring plate 311 therebetween. The inner diameter of the ring plate 311 is smaller than the both outward flange portions 312b and 313b by a predetermined length, and the inner peripheral side end projects inward in the radial direction by that amount. End surface gears 315 and 316 are formed on both end surfaces of the inner peripheral side end of the ring plate 311, respectively. The end surface gears 315 and 316 are uneven in the circumferential direction, and each unevenness is formed to extend radially.

  In the first rotating body 310, small-diameter portions 312 d and 313 d at both ends are rotatably supported via a bearing 317 with respect to the carrier 314. A ring gear 319 that meshes with a pinion gear 318 a fixed to the propeller shaft 318 is fitted on the outer periphery of the large diameter portion 313 a of the second cylindrical member 313. Thereby, the first rotating body 310 receives torque from the drive source of the vehicle via the propeller shaft 318, and can rotate about the axis L1.

  The second rotating body 320 includes a cylindrical portion 321 having a bottomed cylindrical shape and a shaft portion 322 that is coaxially coupled to the outer surface of the bottom portion of the cylindrical portion 321. The outer peripheral surface of the cylindrical part 321 is formed in a two-step staircase shape from the opening side toward the bottom side. Further, the inner peripheral surface of the cylindrical portion 321 is also formed in a two-stepped shape from the opening side toward the bottom side, and a circular recess 323 is formed at the center of the bottom portion. An end surface gear 324 is formed on the opening end surface of the cylindrical portion 321 so as to be uneven in the circumferential direction and formed so that the respective unevenness extends radially. In the second rotating body 320, the shaft portion 322 is inserted into the small diameter portion 312d of the first rotating body 310, and the cylindrical portion 321 can rotate around the axis L1 via the bearing 325 on the inner periphery of the large diameter portion 312a. It is supported by. The second rotating body 320 is connected to one output shaft of the left and right wheels of the vehicle.

  The third rotating body 330 includes a cylindrical portion 331 having a bottomed cylindrical shape and a shaft portion 332 that is coaxially coupled to the outer surface of the bottom portion of the cylindrical portion 331. The outer peripheral surface of the cylindrical part 331 is formed in a two-step staircase shape from the opening side toward the bottom side. Moreover, the inner peripheral surface of the cylindrical part 331 is formed in two steps from the opening side toward the bottom side, and a circular recess 333 is formed at the center of the bottom part. Further, a spline 334 having an uneven shape in the circumferential direction is formed on the opening side of the inner peripheral surface of the cylindrical portion 331 with respect to the circular recess 323.

  An end face gear 344 is formed on the opening end face of the cylindrical portion 331. The end face gear 344 is formed in a concavo-convex shape in the circumferential direction so that each concavo-convex shape extends radially. In the third rotating body 330, the shaft portion 332 is inserted into the small diameter portion 313d of the first rotating body 310, and the cylindrical portion 331 can rotate around the axis L1 via the bearing 335 on the inner periphery of the large diameter portion 313a. It is supported by. The third rotating body 330 is connected to one output shaft of the left and right wheels of the vehicle.

  The fourth rotating body 340 includes a disk portion 341 and shaft portions 342 and 343 having a smaller diameter than the disk portions 341 that are coaxially connected to both ends of the disk portion 341 in the axial direction. The diameter of the disk portion 341 is set smaller than the inner diameter of the ring plate 311 and the inner diameter of the end face gear 334 of the first rotating body 310. In addition, splines 347 that are uneven in the circumferential direction are formed on the outer peripheral surface of the shaft portion 343. The spline 347 is provided at a position facing the spline 334 of the third rotating body 430 in the radial direction. The fourth rotating body 340 is configured such that the shaft portion 342 is accommodated in the cylindrical portion 421 of the second rotating body 320 and the shaft portion 343 is accommodated in the cylindrical portion 331 of the third rotating body 330. Has been placed. The fourth rotator 340 increases the differential rotation between the first rotator 310 and the second and third rotators 320 and 330 to be output. That is, the fourth rotating body 340 is increased to a rotation speed corresponding to the differential rotation.

  The yoke 345 is made of a magnetic material and is formed in a cylindrical shape having a U-shaped cross section as a whole. The yoke 345 is supported on the outer periphery of the small diameter portion 313d of the first cylindrical member 313 so as to be rotatable around the axis L1 via a bearing 346. The yoke 345 is attached to a hole case (not shown) fixed to the vehicle body. That is, the yoke 345 is fixedly provided to the vehicle body.

  The inner rings 350 and 351 are formed in a cylindrical shape, and are fixed to the outer peripheral surface of the disk portion 341 of the fourth rotating body 340. The inner rings 350 and 351 are provided such that their axes are inclined at the same angle and the same direction with respect to the axis L1. On the outer circumferential surfaces of the inner rings 350 and 351, rolling surfaces 352 and 353 on which the rolling elements 355 and 356 roll are formed over the entire circumference. The rolling elements 355 and 356 are formed of a plurality of spheres, and are provided so as to roll on the rolling surfaces 352 and 353 of the inner rings 350 and 351.

  The first differential rotation member 360 is formed in a cylindrical shape. On the inner peripheral surface of the first differential rotating member 360, a rolling surface 361 having an arc concave cross section on which the rolling element 355 rolls is formed over the entire circumference. The first differential rotation member 360 is provided coaxially with one inner ring 350 and is provided to be rotatable relative to the inner ring 350 via a rolling element 355. End face gears 362 and 363 are provided on both end faces of the first differential rotation member 360, respectively. The end surface gears 362 and 363 are uneven in the circumferential direction, and are formed so that each unevenness extends radially.

  The end surface gear 362 provided on the end surface on the ring plate 311 side faces the end surface gear 315 provided on the ring plate 31 and meshes with the end surface gear 315 in a part in the circumferential direction. The number of teeth of the end face gear 362 is 50. On the other hand, the end face gear 363 provided on the end face on the second rotating body 320 side faces the end face gear 324 provided on the second rotating body 320 and meshes with the end face gear 324 in a part in the circumferential direction. The number of teeth of the end face gear 363 is 50.

  The first differential rotation member 360 provided in this way includes end face gears 363 and end face gears 324, and end face gears 362 and end face gears 315 that mesh with each other. Only the number of teeth is set to 49, which is one less than the other, so that the first rotating body 310 and the second rotating body 320 are connected so as to be differentially rotatable.

  Similar to the first differential rotation member 360, the second differential rotation member 370 is formed in a cylindrical shape. On the inner peripheral surface of the second differential rotation member 370, a rolling surface 371 having an arc concave cross section on which the rolling element 356 rolls is formed over the entire circumference. The second differential rotation member 370 is provided on the outer peripheral side of the other inner ring 351 so as to be relatively rotatable via a rolling element 356. The second differential rotation member 370 is provided so as to be coaxial with the central axis of the other inner ring 351. End surface gears 372 and 373 are formed on both end surfaces of the second differential rotation member 370 so as to have a concavo-convex shape in the circumferential direction and each concavo-convex shape extending radially.

  The end surface gear 372 provided on the end surface on the ring plate 311 side faces the end surface gear 316 provided on the ring plate 311, and meshes with the end surface gear 316 in a part in the circumferential direction. The number of teeth of the end face gear 372 is 49. On the other hand, the end face gear 373 provided on the end face on the third rotating body 330 side faces the end face gear 344 provided on the third rotating body 330 and meshes with the end face gear 344 in a part in the circumferential direction. The number of teeth of the end face gear 63 is 50.

  The second differential rotation member 370 provided in this way has the number of teeth of the end surface gear 316 provided on the ring plate 311 among the end surface gear 372 and the end surface gear 316 and the end surface gear 373 and the end surface gear 344 that mesh with each other. Only 49 is set to 49, which is one less than the others, so that the first rotating body 310 and the third rotating body 330 are connected so as to be differentially rotatable.

  The clutch unit 380 includes a plurality of first clutch plates 381 that engage with the third rotating body 330 and a plurality of second clutch plates 382 that engage with the fourth rotating body 340. A circular hole larger than the outer diameter of the other shaft portion 343 of the fourth rotating body 430 is formed in the center of each first clutch plate 381, and the outer peripheral surface of the first clutch plate 381 is uneven in the circumferential direction. Is formed. These first clutch plates 381 are engaged with the splines 334 of the third rotating body 330. That is, the first clutch plate 381 is restricted from rotating in the circumferential direction with respect to the third rotating body 330 and is movable in the axial direction.

  A through hole is formed in the center of the second clutch plate 382, and the inner peripheral surface of the second clutch plate 382 is formed in an uneven shape in the circumferential direction. The outer diameter of the second clutch plate 382 is smaller than the inner diameter of the spline 334 of the third rotating body 330. The second clutch plate 382 is engaged with the spline 347 of the shaft portion 343 of the fourth rotating body 340. In other words, the second clutch plate 382 is restricted from rotating in the circumferential direction with respect to the fourth rotating body 340 and is movable in the axial direction. However, the second clutch plate 382 provided on the side closest to the yoke among the plurality of second clutch plates 382 does not move toward the ring plate 311 with respect to the shaft portion 343 of the fourth rotating body 340. Furthermore, the first clutch plates 381 and the second clutch plates 382 are alternately arranged in the axial direction and arranged so as to face each other. That is, the clutch unit 380 can suppress the rotation of the fourth rotating body 340 with respect to the third rotating body 330.

  The electromagnet 390 is housed and disposed inside the yoke 345. The electromagnet 390 is wound with a coil. When a current is supplied to the coil of the electromagnet 390, the first clutch plate 381 and the second clutch plate 382 are drawn toward the electromagnet 390 side, and the first clutch plate 381 and the second clutch plate 382 are engaged.

  In the differential device configured as described above, when no current is supplied to the coil of the electromagnet 390, the first clutch plate 381 and the second clutch plate 382 are completely separated from each other. Torque is not transmitted between the clutch plates 381 and 382. In this case, since the differential gear of the present embodiment has the same gear ratio setting as the differential gear of the first embodiment, the differential gear operates as in the first embodiment. That is, when the first rotating body 310 makes one rotation, the second rotating body 320 rotates by advancing by 1/50 with respect to the first rotating body 310, and the third rotating body 330 rotates in the first rotation. It rotates with a delay of 1/50 rotation with respect to the body 310. Thereby, torque is distributed to the second rotating body 320 and the third rotating body 330 while allowing the differential.

  A differential of 1/50 rotation is generated between the first rotating body 310 and the second and third rotating bodies 320 and 330. In other words, when the first rotating body 310 makes one rotation, the fourth rotating body 340 is accelerated to 50 rotations. Since the rotational speed and the torque are in an inversely proportional relationship, the torque decreases as the rotational speed increases, and increases as the rotational speed decreases. Here, when compared with the 1st rotary body 310 and the 4th rotary body 340, the 1st rotary body 310 will be 50 rotations with respect to 1 rotation of the 1st rotary body 310. FIG. That is, the torque of the fourth rotating body 340 is reduced to 1/50 of the first rotating body 310.

  Next, a case where the maximum current is supplied to the coil of the electromagnet 390 and the first clutch plate 381 and the second clutch plate 382 are completely engaged will be described. In order to completely engage the first clutch plate 381 and the second clutch plate 382, an engagement force greater than the torque applied to the fourth rotating body 340 is required. However, as described above, the torque applied to the fourth rotating body 340 is reduced to 1/50 of the torque applied to the first rotating body 310. Therefore, even if the engagement force by the 1st and 2nd clutch plates 381 and 382 is not so large, both the clutch plates 381 and 382 can be engaged completely.

  As described above, when the first clutch plate 381 and the second clutch plate 382 are completely engaged, the third rotating body 330 and the fourth rotating body 340 are integrated. Accordingly, the first and second differential rotating members 360 and 370 do not swing with respect to the second and third rotating bodies 320 and 330. That is, the first and second differential rotating members 360 and 370 are integrated with the second to fourth rotating bodies 320, 330 and 340. Further, the fact that the first and second differential rotating members 360 and 370 do not swing relative to the second and third rotating bodies 320 and 330 does not swing relative to the first rotating body 310. become. Therefore, the first and second differential rotating members 360 and 370 are integrated with the first rotating body 310. In this case, when the first rotator 310 is rotated by receiving torque from the drive source of the vehicle, all rotate integrally. That is, the torque itself received by the first rotating body 310 is output to the second and third rotating bodies 320 and 330.

  Further, when the first clutch plate 381 and the second clutch plate 382 are not in a completely engaged state but in an intermediate engagement state, the engagement between the first clutch plate 381 and the second clutch plate 382 is not possible. The resultant force may be smaller than that in the above maximum engagement state.

  Therefore, according to the differential device of this embodiment, since the speed change mechanism including the first to fourth rotating bodies 310, 320, 330, and 340 is employed, the size can be reduced with a simple configuration. Can be realized. In addition, since the clutch mechanism is realized by effectively using the rotating body having the smallest torque among the four rotating bodies 310, 320, 330, and 340, the clutch unit is reduced in size and the structure is simplified. be able to.

It is sectional drawing in alignment with the axial direction of the differential gear which concerns on Embodiment 1 of this invention. It is sectional drawing which follows the axial direction of the differential gear which concerns on the reference example of this invention. It is the schematic diagram of a harmonic gear, (a) is the figure seen from the left direction of (b), (b) is a sectional view of an axial direction, (c) is seen from the right direction of (b). It is a figure. It is sectional drawing which follows the axial direction of the differential gear which concerns on Embodiment 2 of this invention. It is sectional drawing which follows the axial direction of the differential gear which concerns on Embodiment 3 of this invention.

Explanation of symbols

10, 110, 210, 310 ... first rotating body 20, 120, 320 ... second rotating body 30, 130, 330 ... third rotating body 40, 140, 240A, 240B, 340 ... fourth rotating body 50, 150, 350: First differential rotating member 60, 160, 360 ... Second differential rotating member 45, 46, 145 ... Rolling elements 11, 12, 23, 33, 52, 53, 62, 63 ... End face gears

Claims (5)

A difference between an input shaft that rotates in response to torque of a vehicle drive source and a pair of output shafts, and distributes the torque of the input shafts to the pair of output shafts while allowing a difference between the output shafts. A moving device,
A first rotating element; a second rotating element that can rotate at a different rotational speed from the first rotating element as the first rotating element rotates; and the rotating speeds of the first rotating element and the second rotating element Comprising a first and a second transmission consisting of a third rotating element whose rotational speed is determined according to
The first rotating elements of the first and second transmissions are coupled to each other so as not to rotate relative to each other to form a ring plate, and a first rotating body connected to the input shaft,
Second and third rotating bodies each comprising the second rotating element and connected to each of the output shafts;
The first rotating body and the second or third rotating body are coupled so as to be differentially rotatable, and the first rotating body is rotatable about an axis inclined with respect to the first axis of the first to third rotating bodies. And a second differential rotating member,
A fourth rotating body in which the third rotating elements are coupled so as not to rotate relative to each other, and rotatably support the inner circumference or the outer circumference of the first and second differential rotating members;
A transmission mechanism with
Gears are formed on both end faces of the first rotating body,
A gear is formed on one end surface of the second and third rotating bodies,
Gears that can mesh with the gears of the first to third rotating bodies are formed on both end faces of the first and second differential rotating members,
The number of teeth of each gear is such that when the fourth rotating body is fixed, the second rotating body advances by a difference in the number of teeth from the first rotating body with respect to one rotation of the first rotating body. The differential device is configured to rotate, and the third rotating body is set to rotate with a delay of a difference in the number of teeth from the first rotating body .   The differential device according to claim 1, wherein the speed change mechanism is a differential gear. It said fourth rotary member, a differential device according to claim 1 or 2, characterized in that it is the rotation transmission coupling the rotational speed and controllable control axes. Differential apparatus according to any one of claim 1 to 3, characterized in that it comprises a regulating means for intermittently torque transmission between the fourth rotating body and one of said output shaft. The differential device according to claim 4 , wherein the regulating means is a clutch device.

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