JP2015206372A - Drive force distribution device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drive force distribution device which can secure a press-in area of a second roller with respect to a first roller even if positions of the first roller and the second roller in axial directions are displaced from each other.SOLUTION: A drive force distribution device comprises: a first disc member which is arranged at an external periphery of an input shaft concentrically therewith, and is a disc member having a large outside diameter larger than a diameter of the input shaft; a first roller which is a cylindrical member whose an axial length is formed longer than an axial length of the first disc member, and in which the first disc member is inserted into and fixed to an internal periphery of the first roller concentrically therewith in an axial middle-degree position, an outside diameter of an axial one end is formed larger than an outside diameter of an axial other end, and inside diameters of axial both ends are formed in the same length; a second disc member which is arranged at an external periphery of an output shaft concentrically therewith, and a disc member whose outside diameter is larger than a diameter of the output shaft; and a second roller which is a cylindrical member whose axial length is formed longer than an axial length of the second disc member, and in which the second disc member is inserted into and fixed to an internal periphery of the second roller concentrically therewith in an axial middle-degree position, an outside diameter of an axial one end is formed larger than an outside diameter of an axial other end, and inside diameters of axial both ends are formed in the same length.

Description

  The present invention relates to a driving force distribution device, and more particularly to a driving force distribution device useful as a transfer for a four-wheel drive vehicle.

  As a conventional driving force distribution device, for example, a device as described in Patent Document 1 is known. The driving force distribution device described in this document includes a first roller mechanically coupled to the transmission system of the main drive wheel and a second roller mechanically coupled to the drive system of the driven wheel. By bringing the first roller and the second roller into contact with each other on the outer peripheral surfaces of them, a part of the torque to the main driving wheel can be distributed to the driven wheel and output. In such a driving force distribution device, by adjusting the radial pressing force between the first roller and the second roller, the torque transmission capacity between these rollers, and accordingly, the driving force distribution between the main driving wheel and the sub driving wheel. Can be controlled.

As a mechanism for performing this driving force distribution control, Patent Document 1 discloses that the second roller is made to be relative to the first roller in the radial direction by turning the shaft portion of the second roller around the fixed axis of the housing with a motor or the like. A configuration has been proposed in which the displacement can be controlled to control the radial pressing force between the first roller and the second roller, that is, the distribution of the driving force between the main driving wheel and the sub driving wheel.
That is, the outer periphery of the hollow crankshaft is rotatably provided around the fixed axis of the housing, and the shaft portion of the second roller is rotatably supported in the eccentric hollow hole of the hollow crankshaft. By rotating the second roller around the fixed axis by rotating around the fixed axis, the radial force of the second roller against the first roller is adjusted to control the driving force distribution between the main drive wheel and the sub drive wheel. A possible configuration is proposed.

JP 2012-11794 A

  In the technique described in Patent Document 1, the first roller and the second roller are in contact with each other in the entire axial direction in order to secure a contact area between the first roller and the second roller. However, if the axial positions of the first roller and the second roller deviate, the pressing area of the second roller against the first roller decreases, the surface pressure increases, and the first roller and the second roller wear out early. There was a problem.

  The present invention has been made by paying attention to the above problems, and the object of the present invention is to provide a second roller with respect to the first roller even if the first roller and the second roller are displaced in the axial direction. It aims at providing the driving force distribution apparatus which can ensure a pressing area.

For this purpose, the driving force distribution device according to the present invention is provided coaxially on the outer periphery of the input shaft and has a first disk member that is a disk member having an outer diameter larger than the diameter of the input shaft, and an axial length. A cylindrical member formed longer than the axial length of the first disk member, the first disk member is inserted into the inner periphery at an intermediate position in the axial direction and fixed coaxially, and the outer diameter of one axial end is set. A first roller having a larger diameter than the outer diameter of the other axial end and the same inner diameter at both axial ends;
A second disk member, which is a disk member provided on the outer periphery of the output shaft and coaxially with an outer diameter larger than the diameter of the output shaft; and the axial length is longer than the axial length of the second disk member The formed cylindrical member is inserted in the inner circumference at the middle position in the axial direction and fixed coaxially, and the outer diameter at one axial end is larger than the outer diameter at the other axial end. And a second roller having the same inner diameter at both ends in the axial direction.

  Therefore, even if the axial positions of the first roller and the second roller are shifted, the pressing area of the second roller against the first roller can be ensured.

1 is a schematic plan view showing a power train of a four-wheel drive vehicle including a driving force distribution device according to an embodiment of the present invention as viewed from above the vehicle. It is a vertical side view of the driving force distribution apparatus in FIG. It is a longitudinal front view which shows the crankshaft used with the driving force distribution apparatus shown in FIG. It is operation | movement explanatory drawing of the driving force distribution apparatus shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail based on the illustrated examples.
<Configuration of Example>
FIG. 1 is a schematic plan view showing a power train of a four-wheel drive vehicle equipped with a driving force distribution device 1 according to an embodiment of the present invention as a transfer as viewed from above the vehicle.
The four-wheel drive vehicle shown in FIG. 1 is a rear-wheel drive vehicle in which rotation from the engine 2 is transmitted to the left and right rear wheels 6L and 6R through the rear propeller shaft 4 and the rear final drive unit 5 after being shifted by the transmission 3. Is the base vehicle. Then, a part of the torque to the left and right rear wheels (main drive wheels) 6L, 6R is sequentially passed through the front propeller shaft 7 and the front final drive unit 8 by the driving force distribution device 1, and left and right front wheels (secondary drive wheels) 9L, 9R This is a vehicle that enables four-wheel drive traveling by transmitting to the vehicle.

  As described above, the driving force distribution device 1 distributes and outputs a part of the torque to the left and right rear wheels (main driving wheels) 6L and 6R to the left and right front wheels (secondary driving wheels) 9L and 9R. (Main drive wheels) 6L, 6R and left and right front wheels (secondary drive wheels) 9L, 9R are determined to determine the drive force distribution ratio. In this embodiment, this drive force distribution device 1 is as shown in FIG. Configure.

  In FIG. 2, reference numeral 11 denotes a housing of the driving force distribution device 1, and the input shaft 12 and the output shaft 13 are horizontally inclined in the housing 11 so that the respective rotation axes O 1 and O 2 intersect each other. The input shaft 12 is rotatably supported with respect to the housing 11 by ball bearings 14 and 15 at both ends thereof. Both ends of the input shaft 12 are protruded from the housing 11 under liquid-tight sealing by seal rings 25 and 26, respectively. 2, the left end of the input shaft 12 is drivingly coupled to the output shaft of the transmission 3 (see FIG. 1), and the right end is drivingly coupled to the rear final drive unit 5 via the rear propeller shaft 4 (see FIG. 1).

  Arranged near the both ends of the input shaft 12 and the output shaft 13, respectively, a pair of bearing supports 16, 17 are installed between the input / output shafts 12, 13, and the bearing supports 16, 17 are arranged in the middle of each bolt. (Not shown) is attached to the axially opposed inner wall of the housing 11. Here, the bearing supports 16 and 17 may not be fixed to the housing 11. The bearing supports 16 and 17 include input shaft through holes 16a and 17a through which the input shaft 12 passes, output shaft through holes 16c and 17c through which the output shaft 13 and the crankshafts 51L and 51R pass, and input shaft through holes 16a, It has vertical walls 16b and 17b connecting between 17a and the output shaft through holes 16c and 17c, and has a substantially glasses shape when viewed from the front in the axial direction. Roller bearings 21 and 22 are interposed between the bearing supports 16 and 17 and the input shaft 12 so that the input shaft 12 can be rotated with respect to the bearing supports 16 and 17. However, the input shaft 12 is rotatably supported in the housing 11.

  A first cylindrical member 31e is provided in the middle of the input shaft 12 in the axial direction. The first cylindrical member 31e is formed in a cylindrical shape, and is fixed so that the input shaft 12 is inserted into the inner periphery and rotates integrally with the input shaft 12. A first disk member 31d is provided on the outer periphery of the first cylindrical member 31e, and the outer periphery of the first disk member 31d projects radially outward from between the bearing supports 16,17. The first disk member 31d is formed in a disk shape having a through hole in the axial center, and the axial length is shorter than that of the first cylindrical member 31e. The first cylindrical member 31e is inserted into the inner periphery of the first cylindrical member 31e, and is fixed so as to rotate integrally with the first cylindrical member 31e, that is, integrally with the input shaft 12, near the center of the first cylindrical member 31e. ing.

  A first roller 31 is provided on the outer periphery of the first disk member 31d. The first roller 31 is formed in a barrel shape whose outer periphery is curved in the axial direction, and a through hole is formed in the axial center portion. The length of the first roller 31 in the axial direction is longer than that of the first disk member 31d. The first disk member 31d is inserted into the inner periphery, and the first disk member 31d is located near the center of the first roller 31. It is fixed so as to rotate integrally, that is, integrally with the input shaft 12. The inner diameter of the first roller 31 is equally formed over the entire axial direction. On the other hand, the outer diameter of the first roller 31 is formed at a middle height near the center, and the diameter on one end side (the side on which the input shaft 12 and the output shaft 13 open) is made larger than the diameter on the other end side. . The angle of the line connecting the one end side and the other end side of the outer diameter of the first roller 31 is formed to be about half of the angle formed by the input shaft 12 and the output shaft 13. In the present embodiment, the first cylindrical member 31e, the first disk member 31d, and the first roller 31 are formed separately, but these may be formed integrally.

  A second cylindrical member 32e is provided in the middle of the output shaft 13 in the axial direction. The second cylindrical member 32e is formed in a cylindrical shape, and is fixed so that the output shaft 13 is inserted into the inner periphery and rotates integrally with the output shaft 13. A second disk member 32d is provided on the outer periphery of the second cylindrical member 32e, and the outer periphery of the second disk member 32d protrudes radially outward from between the crankshafts 51L and 51R. The second disk member 32d is formed in a disk shape having a through hole at the center, and the axial length is shorter than that of the second cylindrical member 32e. The second cylindrical member 32e is inserted into the inner periphery of the second cylindrical member 32e, and is fixed so as to rotate integrally with the second cylindrical member 32e, that is, integrally with the output shaft 13, near the center of the second cylindrical member 32e. ing.

  A second roller 32 is provided on the outer periphery of the second disk member 32d. The second roller 32 is formed in a truncated cone shape having a through hole in the axial center. The length of the second roller 32 in the axial direction is longer than that of the second disk member 32d. The second disk member 32d is inserted into the inner periphery, and the second disk member 32d is located near the center of the second roller 32. It is fixed so as to rotate integrally, that is, integrally with the output shaft 13. The inner diameter of the second roller 32 is equally formed over the entire axial direction. On the other hand, the outer diameter of the second roller 32 is formed such that the diameter on one end side (the side on which the input shaft 12 and the output shaft 13 are opened) is larger than the diameter on the other end side. The angle of the line connecting the one end side and the other end side of the outer diameter of the second roller 32 is formed to be about half of the angle formed by the input shaft 12 and the output shaft 13. In the present embodiment, the second cylindrical member 32e, the second disk member 32d, and the second roller 32 are formed separately, but they may be formed integrally.

  A holding groove 31b is formed by both side surfaces in the axial direction of the first disk member 31d, the outer peripheral surface of the first cylindrical member 31e, and the inner peripheral surface of the first roller 31. Thrust bearings 31cL and 31cR are held in the holding groove 31b. Has been. Further, a holding groove 32b is formed by both side surfaces in the axial direction of the second disk member 32d, the outer peripheral surface of the second cylindrical member 32e, and the inner peripheral surface of the second roller 32. Thrust bearings 32cL and 32cR are formed in the holding groove 32b. Is held. The thrust bearings 31cL and 31cR contact the side walls 16a1 and 17a1 of the bearing supports 16 and 17, thereby positioning the first roller 31 in the axial direction. On the other hand, the thrust bearings 32cL and 32cR position the second roller 32 in the axial direction by abutting against roller side abutting portions 51Ld and 51Rd of crankshafts 51L and 51R, which will be described later.

The output shaft 13 is pivotally supported on the bearing supports 16 and 17 in the vicinity of both ends 13L and 13R, so that the output shaft 13 is pivotally supported in the housing 11 via the bearing supports 16 and 17.
Thus, when the output shaft 13 (13L, 13R) is rotatably supported with respect to the bearing supports 16, 17, the following eccentric support structure is used.

A hollow outer shaft type crankshaft 51L, 51R is loosely fitted between the output shaft 13 (13L, 13R) and the bearing supports 16, 17 through which the output shaft 13 (13L, 13R) passes.
The crankshaft 51L and the output shaft 13 (13L) protrude from the housing 11 at the left end in FIG. 2, respectively, and the seal ring 27 is interposed between the housing 11 and the crankshaft 51L at the protruding portion. By interposing a seal ring 28 between (13L), the crankshaft 51L protruding from the housing 11 and the protruding portion of the output shaft 13 (13L) are liquid-tightly sealed.

In FIG. 2, the left end 13L of the output shaft 13 discharged from the housing 11 is drivingly coupled to the left and right front wheels 9L and 9R via the front propeller shaft 7 (see FIG. 1) and the front final drive unit 8.
The roller shafts 52L and 52R are interposed between the hollow holes 51La and 51Ra (radius Ri) of the crankshafts 51L and 51R and the corresponding ends 13L and 13R of the output shaft 13, respectively, so that the output shaft 13 (13L and 13R) Are supported in the hollow holes 51La and 51Ra of the crankshafts 51L and 51R so as to freely rotate around the central axis O2.

  As clearly shown in FIG. 3, the hollow holes 51La and 51Ra (center axis O2) of the crankshafts 51L and 51R are eccentric hollow holes eccentric to the outer peripheral portions 51Lb and 51Rb (center axis O3, radius Ro). The central axis O2 of the holes 51La and 51Ra is offset from the central axis O3 of the outer peripheral portions 51Lb and 51Rb by an eccentricity ε between them.

  The outer peripheries 51Lb and 51Rb of the crankshafts 51L and 51R are rotatable to the inner periphery of the output shaft through holes 16c and 17c of the bearing supports 16 and 17 on the corresponding side via roller bearings 53L and 53R, which are radial bearings, respectively. To support. Further, the roller side contact portions 51Ld and 51Rd of the crankshafts 51L and 51R are rotatably supported by the thrust bearings 32cL and 32cR. Further, the thrust bearings 32cL, 32cR and axial bearings 54L, 54R are disposed on the outer side in the axial direction. The crankshafts 51L and 51R are rotatably supported by contacting with each other.

The spacers 60L and 60R are in contact with the wall surfaces 16b1 and 17b1 of the vertical walls 16b and 17b facing the second roller 32 and are on the inner diameter side of the inner peripheral surfaces of the output shaft through holes 16c and 17c. First spacer portions 61L and 61R extending to a position not in contact with 51R, and second spacer portions 62L and 62R (extending portions) extended so as to be inserted into the output shaft through holes 16c and 17c. .
Then, the spacers 60L and 60R are positioned in the radial direction by abutting between the outer periphery of the second spacer portions 62L and 62R and the inner peripheral surfaces of the output shaft through holes 16c and 17c, and the roller bearings 53L and 53R And mutual interference between the thrust bearings 54R and 54L.

  As described above, the first spacer portions 61L and 61R are extended to the inner diameter side, and the thrust bearings 54R and 54L are provided along the radial length of the first spacer portions 61L and 61R. It is possible to increase the bearing capacity without incurring any increase in the size. Further, even if the clearance between the crankshafts 51L, 51R and the inner periphery of the output shaft through holes 16c, 17c of the bearing supports 16, 17 is increased by increasing the size of the roller bearings 53L, 53R, the first spacer portions 61L, The thrust bearings 54L and 54R can be received on the inner diameter side by 61R, and an increase in the radial direction can be avoided.

  Further, since the radial positioning is performed on the outer periphery of the second spacer portions 62L and 62R, the contact between the spacers 60L and 60R and the crankshafts 51L and 51R can be avoided, and the friction loss due to the increase of the sliding resistance is suppressed. be able to. That is, the crankshafts 51L and 51R rotate relative to the bearing supports 16 and 17, while the spacers 60L and 60R do not rotate relative to the bearing supports 16 and 17. Therefore, a sliding location can be reduced by performing positioning using non-rotating members.

  Ring gears 51Lc and 51Rc of the same specification are integrally provided at adjacent ends of the crankshafts 51L and 51R that face each other, and a common crankshaft drive pinion 55 is engaged with the ring gears 51Lc and 51Rc, respectively. 55 is coupled to the pinion shaft 56.

  When the crankshaft drive pinion 55 is meshed with the ring gears 51Lc and 51Rc as described above, the rotational positions where the outer peripheral portions 51Lb and 51Rb of the crankshafts 51L and 51R are aligned with each other in the circumferential direction and have the same phase. In this state, the crankshaft drive pinion 55 is engaged with the ring gears 51Lc and 51Rc.

  Both ends of the pinion shaft 56 are rotatably supported with respect to the housing 11 by bearings 56a and 56b. The right end of the pinion shaft 56 on the right side of FIG. 2 penetrates through the housing 11 and is exposed from this, and the exposed end surface of the pinion shaft 56 is an output shaft of the inter-roller pressing force control motor 35 attached to the housing 11. 35a is drive-coupled by serration fitting or the like. Therefore, when the rotational positions of the crankshafts 51L and 51R are controlled by the inter-roller radial pressing force control motor 35 via the pinion 55 and the ring gears 51Lc and 51Rc, the rotational axis O2 of the output shaft 13 and the second roller 32 is shown in FIG. It turns around the central axis O3 along a locus circle α indicated by a broken line.

  As will be described in detail later, the second roller 32 moves to the first roller 31 as shown in FIGS. 4A to 4C by the rotation of the rotation axis O2 (second roller 32) along the locus circle α in FIG. On the other hand, the distance between the roller axes L1 of the first roller 31 and the second roller 32 approaches the radial direction, and the radius of the first roller 31 and the radius of the second roller 32 increase as the rotation angle θ of the crankshafts 51L and 51R increases. It can be made smaller than the sum value. Due to such a decrease in the distance L1 between the roller shafts, the radial pressing force of the second roller 32 against the first roller 31 (the transmission torque capacity between the rollers: traction transmission capacity) increases, and according to the degree of decrease in the distance L1 between the roller axes. The inter-roller radial pressing force (inter-roller transmission torque capacity: traction transmission capacity), that is, the driving force distribution ratio can be arbitrarily controlled.

  As shown in FIG. 4 (a), in this embodiment, the second roller rotation axis O2 is located immediately below the crankshaft rotation axis O3, and the distance L1 between the first roller 31 and the second roller 32 is the maximum. The distance L1 between the roller shafts at the bottom dead center is made larger than the sum of the radius of the first roller 31 and the radius of the second roller 32. Thereby, at the bottom dead center of the crankshaft rotation angle θ = 0 °, the first roller 31 and the second roller 32 are not pressed against each other in the radial direction, and traction is transmitted between the rollers 31 and 32. No traction transmission capacity = 0, and the traction transmission capacity is between 0 at the bottom dead center and the maximum value obtained at the top dead center (θ = 180 °) shown in Fig. 4 (c). Can be controlled arbitrarily. In the present embodiment, the description will be made assuming that the rotation angle reference point of the crankshafts 51L and 51R is the bottom dead center of the crankshaft rotation angle θ = 0 °.

<Driving force distribution action>
The drive force distribution action of the transfer 1 described above with reference to FIGS. 1 to 4 will be described below. On the other hand, the torque that has reached the input shaft 12 of the transfer 1 from the transmission 3 (see FIG. 1) passes directly from the input shaft 12 through the rear propeller shaft 4 and the rear final drive unit 5 (both see FIG. 1) to the left and right rear wheels 6L. , 6R (main drive wheel).

  On the other hand, the transfer 1 controls the rotational position of the crankshafts 51L and 51R via the pinion 55 and the ring gears 51Lc and 51Rc by the motor 35, and the first roller 31 and the second roller 32 have a roller shaft distance L1 (see FIG. 4). Since the rollers 31, 32 have a torque transfer capacity between the rollers according to the radial mutual pressing force, the left and right rear wheels 6L, 6R (main A part of the torque to the drive wheels) is directed from the first roller 31 to the output shaft 13 via the second roller 32, and the left and right front wheels 9L and 9R (secondary drive wheels) can also be driven. Thus, the vehicle is capable of four-wheel drive running by driving all of the left and right rear wheels 6L and 6R (main drive wheels) and the left and right front wheels (secondary drive wheels) 9L and 9R.

  Note that the radial pressing reaction force between the first roller 31 and the second roller 32 during the transmission is received by the bearing supports 16 and 17 which are rotation support plates common to these rollers, and does not reach the housing 11. The radial pressing reaction force is 0 when the crankshaft rotation angle θ is 0 ° to 90 °, and increases as θ increases while the crankshaft rotation angle θ is 90 ° to 180 °. The maximum value is obtained when the crankshaft rotation angle θ is 180 °.

  During such four-wheel drive running, the rotation angle θ of the crankshafts 51L and 51R is 90 ° of the reference position as shown in FIG. 4B, and the first roller 31 and the second roller 32 are mutually connected. In the case of frictional contact by pressing with a radial pressing force corresponding to the offset amount OS at the time, the power to the left and right front wheels (sub driven wheels) 9L, 9R with the traction transmission capacity corresponding to the offset amount OS between these rollers Transmission takes place.

  Then, the crankshafts 51L and 51R are rotated from the reference position in FIG. 4B toward the top dead center of the crankshaft rotation angle θ = 180 ° shown in FIG. 4C to increase the crankshaft rotation angle θ. As a result, the distance L1 between the roller shafts further decreases, and the mutual overlap amount OL of the first roller 31 and the second roller 32 increases. As a result, the first roller 31 and the second roller 32 increase the radial mutual pressing force. Thus, the traction transmission capacity between these rollers can be increased.

  When the crankshafts 51L and 51R reach the top dead center position in FIG. 4 (c), the first roller 31 and the second roller 32 are in the radial direction with the maximum radial pressing force corresponding to the maximum overlap amount OL. The traction transmission capacity between them can be maximized. The maximum overlap amount OL is the sum of the eccentric amount ε between the second roller rotation axis O2 and the crankshaft rotation axis O3 and the offset amount OS described above with reference to FIG.

  As is apparent from the above description, the crankshaft rotation angle is controlled by rotating the crankshafts 51L and 51R from the rotation position of the crankshaft rotation angle θ = 0 ° to the rotation position of the crankshaft rotation angle θ = 180 °. As θ increases, the traction transmission capacity between rollers can be continuously changed from 0 to the maximum value. Conversely, by rotating the crankshaft 51L, 51R from the rotation position of the crankshaft rotation angle θ = 180 ° to the rotation position of θ = 0 °, the traction between the rollers as the crankshaft rotation angle θ decreases. The transmission capacity can be continuously changed from the maximum value to 0, and the traction transmission capacity between the rollers can be freely controlled by rotating the crankshafts 51L and 51R.

<Securing the roller pressing area>
In order to suppress wear of the first roller 31 and the second roller 32, it is necessary to increase the pressing area of the second roller 32 against the first roller 31 to reduce the surface pressure. One method for increasing the pressing area of the second roller 32 against the first roller 31 is to increase the diameters of the first roller 31 and the second roller 32. However, this method has a problem that the distance between the input shaft 12 and the output shaft 13 is increased, and the driving force distribution device 1 is increased in size. As another method for increasing the pressing area of the second roller 32 against the first roller 31, the axial length of the first roller 31 or the second roller 32, or the axial length of the first roller 31 and the second roller 32. It is possible to lengthen the length. This is also desirable from the viewpoint of securing a pressing area of the second roller 32 against the first roller 31 even if an axial shift occurs between the first roller 31 and the second roller 32.

  In order to suppress the overall weight increase while securing the axial lengths of the first roller 31 and the second roller 32, the axial lengths of the first disk member 31d and the second disk member 32d are set to the first roller 31. The axial length of the second roller 32 needs to be shorter. The first roller 31 and the second roller 32, the first disk member 31d, and the second disk member 32d are secured in the vicinity of the central portion in the axial direction of the first roller 31 and the second roller 32 from the viewpoint of securing the strength of the joint. It is desirable to join the first disk member 31d and the second disk member 32d. With such a structure, the first roller 31 is disposed on the outer peripheral side of the thrust bearings 31cL and 31cR, and the second roller 32 is disposed on the outer peripheral side of the thrust bearings 32cL and 32cR.

Further, since the rotation axis O1 of the input shaft 12 and the rotation axis O2 of the output shaft 13 are inclined with respect to each other, in order to increase the pressing area of the second roller 32 against the first roller 31, the first roller 31 The outer peripheral surface 31a of the second roller 32 and the outer peripheral surface 32a of the second roller 32 need to be inclined according to the angle formed by the rotational axis O1 of the input shaft 12 and the rotational axis O2 of the output shaft 13.
Considering weight reduction while ensuring the strength of the first roller 31 and the second roller, it is better to form the first roller 31 and the second roller 32 with a uniform thickness in the axial direction. The inner circumferences of the first roller 31 and the second roller 32 are also formed at an angle inclined in the axial direction. In this case, the groove widths of the holding grooves 31b, 32b on both side surfaces of the first disk member 31d and the second disk member 32d are different, and the thrust bearings 31cL, 31cR, 32cL, 32cR held there are arranged in the radial direction. It is necessary to arrange things with different widths. That is, it is necessary to use different thrust bearings 31cL, 31cR, 32cL, 32cR on both sides of the first disk member 31d and the second disk member 32d, which leads to an increase in the number of parts, deterioration in production efficiency, and an increase in cost.
In the present embodiment, the inner diameters of the first roller 31 and the second roller 32 are equally formed over the entire axial direction. As a result, the thrust bearings 31cL and 31cR having the same diameter can be used at both axial ends of the first disk member 31d, and the thrust bearings 32cL and 32cR having the same diameter can be used at both axial ends of the second disk member 32d. The increase in the number of points, the deterioration of production efficiency, and the increase in cost can be suppressed.

As described above, in this embodiment, the following effects can be obtained.
(1) The input shaft 12 that rotates together with the left and right rear wheels 6L and 6R that are the main drive wheel transmission system, and a disk member that is coaxially provided on the outer periphery of the input shaft 12 and has an outer diameter larger than the diameter of the input shaft 12 The first disk member 31d is a cylindrical member having an axial length longer than the axial length of the first disk member 31d, and the first disk member 31d is located at the inner periphery in the axially middle position. The first roller 31 is inserted and fixed on the same axis, the outer diameter of one axial end is larger than the outer diameter of the other axial end, and the inner diameter is the same at both axial ends. It rotates with the left and right front wheels 9L and 9R that are wheel transmission systems, and the output shaft 13 is provided on an axis that obliquely intersects with the axis of the input shaft 12, and the outer periphery of the output shaft 13 is provided coaxially and has an outer diameter. The second disk member 32d is a disk member whose diameter is larger than the diameter of the output shaft 13, and the cylindrical part whose axial length is longer than the axial length of the second disk member 32d. In the middle position in the axial direction, the second disk member 32d is inserted into the inner periphery and fixed coaxially, and the outer diameter at one axial end is made larger than the outer diameter at the other axial end. The second roller 32 having the same inner diameter at both ends in the axial direction and the output shaft 13 are rotatably supported on the rotating shaft of the second roller 32, and the rotating shaft of the second roller 32 is supported by the second roller. The crankshafts 51L and 51R that are rotatably supported around the eccentric axis offset from the rotation axis of 32 and the crankshafts 51L and 51R are rotated to rotate the rotation axis of the second roller 32 around the eccentric axis. A motor 35 (actuator) that distributes driving force to the driven wheels by bringing the outer peripheral surfaces of the first roller 31 and the second roller 32 into frictional contact with each other or traction contact via hydraulic oil, an input shaft 12, and an output shaft 13 , Housing for housing the crankshafts 51L, 51R 11, bearing supports 16, 17 provided between the housing 11 and the input shaft 12, and provided between the bearing supports 16, 17 and both side surfaces of the first disk member 31 d in the axial direction. Are provided between thrust bearings 31cL and 31cR (first thrust bearings) that receive the force in the direction and both axial sides of the crankshafts 51L and 51R and the second disk member 32d, and receive the force in the thrust direction of the output shaft 13 Thrust bearings 32cL and 32cR (second thrust bearings) were provided.
Therefore, even if the axial positions of the first roller 31 and the second roller 32 are shifted, the pressing area of the second roller 32 against the first roller 31 can be ensured. Also, thrust bearings 31cL and 31cR having the same diameter can be used at both axial ends of the first disk member 31d, and thrust bearings 32cL and 32cR having the same diameter can be used at both axial ends of the second disk member 32d. Increase, deterioration of production efficiency, and cost increase can be suppressed.

  As described above, the present invention is not limited to the configuration of the above embodiment, and may have other configurations. For example, in this embodiment, the outer peripheral surface 31a of the first roller 31 and the outer peripheral surface 32a of the second roller 32 are both inclined, but only one of them may be inclined.

1 Driving force distribution device
11 Housing
12 Input shaft
13 Output shaft
16 Bearing support
17 Bearing support
31 1st roller
31cL thrust bearing (first thrust bearing)
31cR thrust bearing (first thrust bearing)
31d First disk member
32 Second roller
32cL thrust bearing (second thrust bearing)
32cR thrust bearing (second thrust bearing)
32d Second disk member
35 Motor (actuator)
51L, 51R Crankshaft

Claims (1)

An input shaft that rotates with the main drive wheel transmission system;
A first disk member, which is a disk member provided coaxially on the outer periphery of the input shaft and having an outer diameter larger than the diameter of the input shaft;
A cylindrical member having an axial length longer than the axial length of the first disk member, and the first disk member is inserted into the inner periphery at an axially middle position and fixed coaxially. A first roller having an outer diameter at one axial end larger than an outer diameter at the other axial end, and having the same inner diameter at both axial ends;
An output shaft provided on an axis that rotates together with the driven wheel transmission system and obliquely intersects the axis of the input shaft;
A second disk member that is a disk member that is provided on the outer periphery of the output shaft on the same axis and whose outer diameter is larger than the diameter of the output shaft;
A cylindrical member having an axial length longer than the axial length of the second disk member, the second disk member being inserted into the inner periphery at an intermediate position in the axial direction and fixed coaxially, A second roller having an outer diameter at one end in the axial direction larger than an outer diameter at the other end in the axial direction, and having the same inner diameter at both ends in the axial direction;
A crank that rotatably supports the output shaft on the rotation shaft of the second roller, and supports the rotation shaft of the second roller so as to be rotatable around an eccentric axis offset from the rotation shaft of the second roller. A shaft,
The crankshaft is rotated to rotate the rotation shaft of the second roller around the eccentric axis, and the outer peripheral surfaces of the first roller and the second roller are brought into friction contact with each other or traction contact via hydraulic oil. An actuator for distributing the driving force to the driven wheels by
A housing that houses the input shaft, the output shaft, and the crankshaft;
A bearing support provided between the housing and the input shaft;
A first thrust bearing provided between the bearing support and both axial side surfaces of the first disk member and receiving a thrust force of the input shaft;
A second thrust bearing provided between the crankshaft and both axial side surfaces of the second disk member and receiving a thrust force of the output shaft;
A driving force distribution device characterized by comprising:

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