JP2015067060A - Steering mechanism of in-wheel motor drive device mounted vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steering mechanism which secures sufficient allowances for length adjustment in a tie rod connected with an in-wheel motor drive device.SOLUTION: A steering mechanism of an in-wheel motor drive device mounted vehicle includes: an in-wheel motor drive device capable of steering; and a tie rod 21 which connects the in-wheel motor drive device with a steering gear box. The tie rod includes: a tie rod body 22 extending from the steering gear box; a tie rod tip member 24 provided at the in-wheel motor drive device; and a straight tie rod length adjustment member 23 which is threadedly engaged with a female screw hole formed at the tie rod body and is threadedly engaged with a female screw hole 247 formed at the tie rod tip member.

Description

  The present invention relates to an in-wheel motor drive device that drives steered wheels of a vehicle, and more particularly to a steering mechanism that applies a turning force to the in-wheel motor drive device.

  The in-wheel motor drive device is not only less burdensome on the environment because it is electrically driven, but also installed in the wheel of an automobile to drive the wheel, so that it has a larger cabin than an engine automobile. Space can be secured, which is advantageous. As a method of driving a steered wheel with an in-wheel motor drive device, for example, as described in Non-Patent Document 1, a technique for suspending an in-wheel motor drive device with a high-mount double wishbone suspension device has been proposed. Yes.

Satoshi Murata, "Development of 139-20105175 In-wheel Motor Drive Unit", Academic Lecture Preprint No.28-10, Japan Automobile Engineers Association, 2010

  By the way, when the steered wheels are driven by the in-wheel motor drive device, the in-wheel motor drive device is connected to a tie rod extending outward in the vehicle width direction from a steering gear box arranged at the center in the vehicle width direction. As the wheel moves in the vehicle width direction, the steered wheels steer left or right.

  The tie rod can be adjusted in length to adjust the toe angle of the steered wheels, to adjust the steered direction, or to inspect and maintain the in-wheel motor drive device. The length-adjustable tie rod has a tie rod end 121 on the outer side in the vehicle width direction and a straight shaft portion 123 having an external thread on the outer periphery as shown in FIG. Have inside. The outer end of the tie rod end 121 in the vehicle width direction is connected to the knuckle arm 111 via a ball joint 124. A female screw hole 125 is provided at the inner end in the vehicle width direction of the tie rod end 121, and the female screw hole 125 is screwed with the outer end in the vehicle width direction of the shaft portion 123. The inner end in the vehicle width direction of the shaft portion 123 is connected to the steering gear box 131. Further, a locking nut 122 for preventing loosening is screwed into the male screw of the shaft portion 123 so as not to loosen with respect to the female screw hole 125 of the tie rod end 121. To adjust the length of the tie rod, the lock nut 122 is loosened, and the shaft portion 123 arranged on the inner side in the vehicle width direction is rotated relative to the tie rod end 121 so that the length of the shaft portion 123 entering the female screw hole 125 is increased. This is done by tightening the lock nut 122 again.

  On the other hand, the dimension in the vehicle width direction of the in-wheel motor drive device is much larger than the dimension in the vehicle width direction of a general automobile knuckle that supports the steered wheels of an engine automobile. For this reason, the space from the steering gear box to the in-wheel motor drive device is restricted, and it is not possible to secure a sufficient space for storing the tie rods extending in the vehicle width direction, and the tie rod length adjustment allowance is short. There is a problem in spatial constraints that it becomes.

  Moreover, since the in-wheel motor drive device incorporates a rotor and a stator, its radial dimension is designed to be much larger than the knuckle for automobiles of steered wheels of engine automobiles. For this reason, when the in-wheel motor drive device having a substantially columnar shape with a large vehicle width direction dimension and a radial direction dimension is steered, it must be prevented from interfering with the tie rod, and cannot be formed into a straight shape. There are also restrictions.

  As described above, the tie rod connected to the in-wheel motor drive device has large space and shape restrictions, and a sufficient length adjustment margin cannot be obtained. In view of the above circumstances, an object of the present invention is to provide a sufficient length adjustment allowance in a tie rod connected to an in-wheel motor drive device.

  For this purpose, the steering mechanism of the vehicle equipped with the in-wheel motor drive device according to the present invention is arranged on the inner side in the vehicle width direction with the in-wheel motor drive device attached to the steerable wheel arranged on the outer side in the vehicle width direction. A tie rod is connected to the steering gear box. The tie rod is bent and extended between the end and the tip, the end is rotatably connected to the steering gear box, and the tip is extended to the vehicle width direction outer side and the in-wheel motor drive device. A tie rod tip member that is movably connected, and a straight tie rod length adjusting member that has one end connected to the tip of the tie rod body and the other end connected to the tie rod tip member. According to the present invention, it is possible to configure the outer end portion of the tie rod in the vehicle width direction with the tie rod tip member and the tie rod length adjusting member, and the adjusting member for adjusting the length of the tie rod is set in the vehicle width direction of the tie rod. Can be placed on the outside. Therefore, it is possible to solve the problem of space restriction unique to the in-wheel motor drive device.

  Further, by arranging all or part of the tie rod length adjusting member in the space area inside the road wheel of the steered wheel, the length of the tie rod length adjusting member can be sufficiently secured. Thereby, the tie rod connected to the in-wheel motor drive device can have a sufficient length adjustment allowance. The tie rod length adjusting member may be a linear member that adjusts the distance from the tip of the tie rod body to the tie rod tip member, and the configuration thereof is not particularly limited. For example, the tie rod length adjusting member is a bolt in which a male screw is formed. Alternatively, a plurality of types of tie rod length adjusting members having different lengths are prepared, and a tie rod length adjusting member having a desired length is used for the tie rod. Further, the tie rod main body only needs to bend and extend at least one portion between the end and the tip, and the other portion may extend linearly.

  As one embodiment of the present invention, a tie rod tip member includes a joint portion that is rotatably connected to an in-wheel motor drive device, and one surface and the other surface that extend from one end to the other end and extend from one end to the other end. And a base provided with a joint portion on one surface of one end and a projecting piece provided on the other surface of the other end of the base. The tie rod length adjusting member is connected to the protruding piece of the tie rod tip member, and extends substantially parallel to one end of the base portion on the other surface side of the base portion of the tie rod tip member. According to this embodiment, the tie rod tip member and the tie rod length adjusting member are arranged so as to overlap each other when viewed in the vertical direction or the vehicle longitudinal direction, thereby reducing the overall width of the tie rod in the vehicle width direction, and adjusting the tie rod length adjusting member. It is possible to secure a sufficient length. The joint portion of the tie rod tip member may be, for example, a ball joint or another rotatable structure, and is not particularly limited. The tie rod length adjusting member is, for example, disposed above or below the tie rod tip member, or disposed in front of or behind the tie rod tip member.

  As a preferred embodiment of the present invention, the distal end portion of the tie rod body is positioned higher than the connection point between the tip of the tie rod body and the tie rod length adjusting member. According to such an embodiment, the height direction interval from the end portion of the tie rod body to the road surface can be made larger than that of the conventional embodiment, which is advantageous. Further, the height position of the end portion of the tie rod body can be brought close to the height position of the joint portion of the tie rod tip member.

  The shape of the tie rod body is not particularly limited. In part, the tie rod body may extend straight, or may extend in an arc to avoid interference with other components. As a preferred embodiment of the present invention, in the in-wheel motor drive device, a wheel hub portion, a speed reduction portion, and a motor portion having a larger diameter than the speed reduction portion are sequentially arranged from the outside in the vehicle width direction to the inside. The The tie rod tip member is connected to the outer peripheral portion of the speed reducing portion. The surface of the tie rod body is preferably curved so as to avoid the motor portion. According to this embodiment, the surface of the tie rod body is not formed straight, but is curved so as to be bent, so that the steered wheels are largely turned in the vehicle left turn direction or the vehicle right turn direction. Even if the in-wheel motor drive device approaches the tie rod body by rudder, interference between the two can be avoided. In one embodiment, the surface of the tie rod body may be curved so as to avoid steered wheels driven by an in-wheel motor drive device. According to this embodiment, the surface of the tie rod body is not formed straight, but is curved so as to be bent, so that the steered wheels are largely turned in the vehicle left turn direction or the vehicle right turn direction. Even if the steered wheel is steered and approaches the tie rod body, the interference between the two can be avoided.

  As a further preferred embodiment of the present invention, the tie rod body may be formed such that a portion where the tie rod body is formed is thinner than other portions when viewed in the vertical direction. According to such an embodiment, when the in-wheel motor drive device is closest to the tie rod body at the time of steering, the in-wheel motor drive device is Clearance can be easily secured with the tie rod body, and the maximum turning angle of the steered wheels can be further increased.

  As one embodiment of the present invention, the tie rod body has a curved portion that is wider in the vertical direction than other portions. According to such an embodiment, it is possible to increase the bending strength by increasing the cross-sectional area of the tie rod body at the curved portion. In particular, it is possible to secure a sufficient cross-sectional area of the tie rod body by forming a thin portion in the vertical direction as viewed in the vehicle longitudinal direction. Therefore, even if a part of the tie rod body is formed thin, it is possible to prevent the bending rigidity of the tie rod body from being lowered. As another embodiment, the tie rod body may be formed in an S shape while maintaining a substantially constant cross-sectional shape.

  As one embodiment of the present invention, the outer periphery of both ends of the tie rod length adjusting member is provided with a female screw hole formed at the tip of the tie rod body and a male screw that is screwed into a female screw hole formed in the tie rod tip member. On the outer periphery of the central portion of the tie rod length adjusting member, a grip portion that fits into the tool is provided. According to such an embodiment, the tie rod length adjusting member has one end connected to the tie rod main body by holding the grip portion provided at the longitudinal center of the tie rod length adjusting member with a tool and rotating the tie rod length adjusting member. The other end of the tie rod length adjusting member enters the tie rod tip member while entering the tie rod, and the overall length of the tie rod can be shortened. Or conversely, the entire length of the tie rod can be increased. Therefore, the length of the tie rod can be adjusted efficiently. The shape of the grip portion is, for example, a regular hexagon. As another form, the tie rod length adjusting member has a shaft portion with a male thread formed at one end, a head portion having a diameter larger than that of the shaft portion at the other end, and the shaft portion is a tie rod main body and a tie rod tip member. It may be a general bolt that is screwed into both the female screw holes.

  As described above, according to the present invention, the tie rod length adjusting member for adjusting the toe angle is disposed on the outer side in the vehicle width direction of the tie rod, and the space for storing the tie rod using the space area inside the road wheel of the steered wheel is accommodated. Can be secured sufficiently. Therefore, the tie rod connected to the in-wheel motor drive device can have a sufficient length adjustment allowance, and the toe angle of the steered wheels can be adjusted to a desired value. In addition, the maximum turning angle can be sufficiently secured, and interference between the tie rod and the steered wheel and interference between the tie rod and the in-wheel motor drive device can be prevented. Further, since the tie rod length adjusting member is disposed on the outer side in the vehicle width direction, the in-wheel motor drive device can be easily inspected and maintained.

It is a schematic plan view which shows the turning mechanism of the vehicle mounted with the in-wheel motor drive device which becomes one Embodiment of this invention, and represents a steered wheel in cross section. FIG. 2 is a schematic plan view showing the tie rod of FIG. 1 taken out, and a part thereof is shown in cross section for easy understanding. It is the disassembled perspective view which looked at the tie rod from the vehicle width direction outer side. It is explanatory drawing which looked at the tie rod of FIG. 2 from the vehicle front. It is sectional drawing which expands and represents the tie rod front-end | tip member of FIG. It is explanatory drawing which shows the cross section of a male screw member, and the length adjustment method of a tie rod, Comprising: It represents the state seen from the direction of the arrow by making VI-VI a cross section in FIG. It is a schematic plan view which shows a mode that a steered wheel steers in the vehicle left turning direction in a partial cross section. It is a schematic plan view which shows a mode that a steered wheel steers in the vehicle right turn direction in a partial cross section. It is a schematic sectional drawing which shows the deceleration part of an in-wheel motor drive device. It is the schematic which shows the steering mechanism of the conventional vehicle.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic plan view showing a turning mechanism of a vehicle equipped with an in-wheel motor drive device according to an embodiment of the present invention, and shows a steered wheel in cross section. In FIG. 1, the left side of the drawing represents the inner side in the vehicle width direction, the right side of the drawing represents the outer side in the width direction, the lower side of the drawing represents the front of the vehicle, and the upper side of the drawing represents the rear of the vehicle. FIG. 2 is a schematic plan view showing the tie rod of FIG. 1 taken out, and a part thereof is shown in cross section for easy understanding. FIG. 3 is an exploded perspective view of the tie rod as seen from the outside in the vehicle width direction. FIG. 4 is an explanatory view of the tie rod of FIG. 2 as viewed from the front of the vehicle. FIG. 5 is an enlarged cross-sectional view of the tie rod tip member of FIG. 6 is an explanatory view showing a cross section of the male screw member and a method for adjusting the length of the tie rod, and shows a state taken along the line VI-VI in FIG. 5 and viewed from the direction of the arrow.

  First, the in-wheel motor drive device 11 will be described. The in-wheel motor drive device 11 includes a motor unit 11A, a reduction unit 11B, and a hub unit 11C that are sequentially arranged in series in the axial direction of the in-wheel motor drive device 11. FIG. 1 shows the contour shape of the in-wheel motor drive device 11. The motor part 11A, the reduction part 11B, and the hub part 11C are sequentially arranged in series in the axis O direction of the hub part 11C that is a rotation support member, and are arranged coaxially. The speed reduction part 11B adjacent to the hub part 11C is made larger in diameter than the hub part 11C. The motor part 11A adjacent to the speed reducing part 11B has a larger diameter than the speed reducing part 11B.

  The in-wheel motor drive device 11 drives the steered wheels 101 arranged on the outer side in the vehicle width direction of the vehicle, and is provided in the inner space region S of the road wheel 102 of the steered wheels 101. When the turning angle of the steered wheels 101 is 0 °, the axis O of the in-wheel motor drive device 11 extends in parallel with the vehicle width direction as shown in FIG. As a result, the vehicle travels straight. The in-wheel motor drive device 11 is connected to the steering gear box 71 via the tie rod 21. The steering gear box 71 is disposed at the center in the vehicle width direction of the vehicle, and as shown in FIG. 1, an in-wheel motor drive device 11 disposed on the left side of the vehicle and an in-wheel motor drive device 11 (not shown) disposed on the right side of the vehicle. Connect to A steering force in the vehicle width direction is applied from the steering gear box 71, and the in-wheel motor drive device 11 turns the vehicle counterclockwise as shown by an arrow in FIG. The vehicle is steered in the turning direction L or the vehicle right turn direction R (the lower side in FIG. 1 is the front of the vehicle). The steered wheel 101 is a known wheel including a metal road wheel 102 and an annular rubber tire provided on the outer periphery of the road wheel 102.

  The in-wheel motor drive device 11 is attached to a suspension device (not shown) so that the in-wheel motor drive device 11 can be rotated about the turning axis K. This suspension device is a double wishbone suspension device, a stradded suspension device, or the like. The form is not particularly limited as long as it can be steered.

  The motor unit 11A has a casing with a relatively large outer diameter on the inner side in the vehicle width direction, and the speed reducing unit 11B has a casing with a relatively small outer diameter on the outer side in the vehicle width direction. These casings are non-rotating members that form the outline of the in-wheel motor drive device, whereas the hub portion 11C has a hub wheel that is a rotating member protruding outward in the vehicle width direction from the speed reduction portion 11B at the axial end. The hub wheel of the hub portion 11 </ b> C is connected and fixed to the road wheel 102 of the steered wheel 101 with a plurality of bolts 103.

  The motor unit 11A incorporates a rotor and a stator of a rotating electrical machine in a casing, drives the hub wheel of the hub unit 11C, or performs power regeneration using the rotation of the hub wheel of the hub unit 11C. The speed reduction part 11B incorporates a speed reduction mechanism such as a cycloid speed reducer in the casing, and reduces the rotation of the motor part 11A and transmits it to the hub wheel of the hub part 11C. A terminal box 11T for drawing a power line extending from the inverter to the motor unit 11A is attached to the rear part of the motor unit 11A along the outer peripheral surface of the motor unit 11A.

  Here, the case where a cycloid reducer is adopted as the speed reduction part 11B will be briefly described. As shown in FIG. 9, the speed reduction part 11B includes a disc-shaped eccentric part 15 provided eccentric to the output shaft of the motor part 11A. The curved plate 16 attached to the eccentric portion 15 so as to be a concentric circle, the rolling bearing 29 provided between the outer periphery of the eccentric portion 15 and the inner peripheral surface of the central hole 30b of the curved plate 16, and the reduction portion It has the some outer pin 17 attached to the casing of 11B, and the motion conversion mechanism which takes out rotation of the curve board 16 and outputs it to the steered wheel 101. FIG.

  The outer peripheral edge of the curved plate 16 described above is formed in a wave shape and engages with a plurality of outer pins 17 attached to the casing of the speed reducing portion 11B. The outer pins 17 are arranged at equal intervals in the circumferential direction around the axis O, and are one more than the number of wavy peaks formed on the outer peripheral edge of the curved plate 16. The curved plate 16 rotates slightly when it revolves around the axis O.

  The motion conversion mechanism takes out the rotation of the curved plate 16 and outputs only the rotation to the steered wheels 101, and includes a plurality of through holes 30a formed in the curved plate 16 at intervals in the circumferential direction, The inner pin 28 has an outer diameter smaller than the inner diameter of the through hole 30a and passes through each through hole 30a, and a flange portion (not shown) that commonly supports one end of each inner pin 28. The flange portion is coaxially attached and fixed to the hub wheel of the hub portion 11C. The output shaft of the motor part 11A and the hub wheel of the hub part 11C extend along the axis O, but the eccentric part 15 and the curved plate 16 are arranged eccentrically from the axis O.

  The inner pin 28 is disposed in an annular gap between the inner pin collar 28c, the shaft portion 28a passing through the inner pin collar 28c, and the inner peripheral surface of the inner pin collar 28c and the outer peripheral surface of the shaft portion 28a. Needle 28b. Thus, the inner pin 28 includes a rolling bearing and is in rolling contact with the inner wall surface of the through hole 30a.

  Note that an oil tank 11R is provided below the motor unit 11A and the speed reduction unit 11B so as to protrude further to the outer diameter side than the casing of the motor unit 11A and the speed reduction unit 11B and to store oil that lubricates the motor unit 11A and the speed reduction unit 11B. Is provided.

  Returning to FIG. 1 to FIG. 6, the deceleration portion 11 </ b> B that is relatively located outside in the vehicle width direction and the hub portion 11 </ b> C that is located further outside in the vehicle width direction are the inner space region S of the cylindrical road wheel 102. Placed in. On the other hand, a part of the motor portion 11 </ b> A positioned relatively inward in the vehicle width direction protrudes from the inner space S of the road wheel 102 to the inner side in the vehicle width direction.

  A knuckle arm 11N is provided on the casing that forms the outline of the speed reducing portion 11B. The root of the knuckle arm 11N is continuous with the casing. Further, the tip of the knuckle arm 11N protrudes from the casing and extends forward of the vehicle, and is connected to the tie rod 21 via the ball joint 27 so as to be rotatable.

  Next, a turning mechanism that applies a turning force to the in-wheel motor drive device 11 will be described.

  The steering mechanism of the vehicle equipped with the in-wheel motor drive device includes a tie rod 21 extending in the vehicle width direction. The tie rod 21 connects the in-wheel motor drive device 11 disposed on the outer side in the vehicle width direction and the steering gear box 71 disposed on the inner side in the vehicle width direction. The steering gear box 71 moves the tie rod 21 in the vehicle width direction in accordance with steering of a steering wheel (not shown). Then, the tie rod 21 applies a turning force about the turning axis K to the in-wheel motor drive device 11 to turn the in-wheel motor drive device 11 in the vehicle left turning direction L or the vehicle right turning direction R.

  Referring to FIG. 2, the tie rod 21 includes a tie rod body 22 extending from the steering gear box 71 to the in-wheel motor drive device 11, a tie rod tip member 24 provided in the in-wheel motor drive device 11, and both ends of the tie rod body 22 and A straight rod-like straight male screw member 23 connected to the tie rod tip member 24. The male screw member 23 is a member that adjusts the length of the tie rod 21.

  The tie rod body 22 has the in-wheel motor drive device 11 side as a tip and the steering gear box 71 side as a terminal, and basically extends in the vehicle width direction. The tie rod body 22 is bent and extends between the end and the tip. A female screw hole 221 and a female screw hole 222 are formed at the tip and end of the tie rod body 22, respectively.

  A male screw portion formed on the outer peripheral surface of the distal end portion 25 m of the link 25 is screwed into the female screw hole 221 provided at the end of the tie rod body 22. Further, a nut 254 is screwed into the distal end portion 25m of the link 25. By tightening the nut 254, the distal end portion 25m of the link 25 is prevented from loosening so as not to come out of the female screw hole 221. In this way, the tip 25m of the link 25 is connected and fixed to the tie rod body 22.

  The link 25 is a rod-like body having a straight end portion and a distal end portion and a bent central portion, and a seat portion of a ball joint 26 is provided at the end of the link 25. The ball joint 26 is covered by the boot 72 of the steering gear box 71 and is connected to the tip of the rack 73 of the steering gear box 71. As a result, the link 25 is rotatably connected to the rack 73 via the ball joint 26. When the steered wheel 101 is steered, the link 25 and the tie rod body 22 fixed to each other slightly rotate around the ball joint 26 and change their own extending direction. It should be understood that it extends.

  As shown in FIGS. 3 to 5, the tie rod distal end member 24 is disposed at the distal end of the tie rod 21, and includes a base 241, a ball joint portion 271 that forms part of the ball joint 27, and a protruding piece 246. The tie rod tip member 24 is rotatably connected to the outer peripheral portion of the speed reducing portion 11B of the in-wheel motor drive device 11 via the ball joint 27.

  Specifically, the ball joint 27 has a ball joint portion 271 and a ball portion 272. The ball portion 272 extends in the up-down direction, the upper end portion is formed in an axial shape, and the lower end portion is formed in a spherical shape. The upper end portion of the ball portion 272 is fixedly attached to the distal end portion of the knuckle arm 11N (see FIG. 1) that extends forward from the casing of the speed reduction portion 11B. The ball joint portion 271 has a substantially cylindrical shape with an upper end opening, and an inner spherical surface is formed on the inner periphery of the ball joint portion 271. The inner spherical surface of the ball joint portion 271 surrounds the ball spherical surface at the lower end of the ball portion 272 so as to be relatively rotatable, and is prevented from coming off so that the ball portion 272 does not come out of the ball joint portion 271.

  The base 241 of the tie rod tip member 24 has one end 242 and the other end 243. The base portion 241 has a first surface 244 and a second surface 245 that extend from one end 242 to the other end 243. In the present embodiment, one surface 244 faces upward and the other surface 245 faces downward. A ball joint portion 271 is integrally provided on one surface 244 of the one end 242 of the base portion 241. A protruding piece 246 is integrally provided on the other surface 245 of the base portion 241. However, the protruding piece 246 is disposed at a position away from the one end 242 of the base portion 241, for example, at the other end 243 or near the other end 243. A protruding piece 246 protruding from the other surface 245 is formed with a female screw hole 247 passing therethrough. The imaginary axis P of the female screw hole 247 extends on the other surface 245 side of the base portion 241 and substantially parallel to the extending direction from the one end 242 to the other end 243 of the base portion.

  The male screw member 23 is a linear rod body, and is a bolt having both ends formed as male screws. Male threads in opposite directions are formed on the outer peripheral surfaces of both end portions 231 and 232 of the male screw member 23. In addition, a grip portion 235 that fits with a work tool such as a wrench is formed at the center in the longitudinal direction of the male screw member 23. The grip portion 235 may have a polygonal cross section such as a regular hexagon, or may have another shape. One end 231 of the male screw member 23 is screwed into a female screw hole 222 formed through the end of the tie rod body 22. Further, a nut 233 is screwed into one end portion 231 of the male screw member 23, and by tightening the nut 233, the one end portion 231 of the male screw member 23 is prevented from coming loose from the female screw hole 222. In this way, the one end 231 of the male screw member 23 is connected and fixed to the tie rod body 22. The other end 232 of the male screw member 23 is screwed into the female screw hole 247 of the tie rod tip member 24. Further, a nut 234 is screwed into the other end portion 232 of the male screw member 23, and the other end portion 232 of the male screw member 23 is prevented from coming loose from the female screw hole 247 by tightening the nut 234. In this way, the other end 232 of the male screw member 23 is connected and fixed to the tie rod tip member 24.

  When the turning angle of the steered wheel 101 with the in-wheel motor drive device 11 is 0 °, the tie rod tip member 24 and the male screw member 23 arranged on the outer side in the vehicle width direction of the tie rod 21 and the tip portion of the tie rod body 22 are Located in the inner space S. On the other hand, the end portion of the tie rod body 22 located on the inner side in the vehicle width direction of the tie rod 21 is located on the inner side in the vehicle width direction than the steered wheels 101 (see FIG. 1).

  Next, the tie rod body 22 of the tie rod 21 will be described in detail with reference to FIG. The tie rod main body 22 extends substantially in the vehicle width direction, and has a female screw hole 222 for screwing with the male screw member 23 at a distal end that is an outer end in the vehicle width direction.

  However, the tie rod body 22 is not a straight rod-like body, but is bent and formed in a substantially S shape when viewed in the vertical direction of the vehicle. Further, when the tie rod body 22 is observed in the vertical direction of the vehicle, the thickness is not constant in the longitudinal direction, and the thickness continuously changes according to the position in the longitudinal direction. That is, referring also to FIG. 1, the end portion of the tie rod body 22 including the bottomed female screw hole 221 has an inner diameter side portion 223 that faces the in-wheel motor drive device 11 as an inner diameter side and an outer side portion that faces the rim portion 104 outside. It extends in an arc shape on the radial side, and its cross-sectional shape is circular. Further, the tip portion of the tie rod body 22 including the female screw hole 222 formed as a through hole has an inner diameter side portion 224 facing the rim portion 104 of the road wheel 102 as an inner diameter side, and a side portion facing the outer peripheral surface of the in-wheel motor drive device 11. The cross-sectional shape is a rectangle that is long in the vertical direction and short in the horizontal direction. That is, the front end portion of the tie rod main body 22 on the outer side in the vehicle width direction and the end portion on the inner side in the vehicle width direction are bent in opposite directions. The central portion in the longitudinal direction of the tie rod main body 22 that integrally connects the distal end portion and the distal end portion extends substantially linearly, and the cross-sectional shape is basically a rectangle that is long in the vertical direction and short in the horizontal direction. However, the cross-sectional shape of the central portion in the longitudinal direction continuously changes according to the longitudinal position of the tie rod body 22.

  A curved surface 225 is formed on the surface of the central portion of the tie rod body 22 in the longitudinal direction. The curved surface 225 is a surface that faces the in-wheel motor drive device 11 and is formed so as to form a concave curved surface. The curved surface 225 is adjacent to an inner diameter side portion 223 that is formed at the end portion of the tie rod body 22 and faces the in-wheel motor drive device 11.

  In addition, the tie rod body 22 has a longitudinal center portion including an inner diameter side portion 224 that is curved so as to avoid the steered wheels 101 in a vertical direction as shown in FIG. 2, and is thinner than both ends of the tie rod body 22. It is formed. Further, the central portion in the longitudinal direction is made wider in the vertical direction than both end portions of the tie rod body 22 as shown in FIG.

  The manner in which the in-wheel motor drive device 11 and the steered wheels 101 are steered will be described with reference to the plan views of FIGS. 7 and 8. When the steering gear box 71 pushes the tie rod 21 outward in the vehicle width direction and the steered wheel 101 is steered in the vehicle left turning direction L as shown in FIG. 7, the motor portion 11A of the in-wheel motor drive device 11 is the tie rod main body 22. To approach. However, since the tie rod main body 22 is covered by the inner diameter side portion 223 that faces the motor portion 11A, interference with the motor portion 11A can be avoided.

  On the contrary, when the steering gear box 71 pulls the tie rod 21 inward in the vehicle width direction and steers the steered wheel 101 in the vehicle right turn direction R as shown in FIG. Approaches the tie rod body 22. However, since the tie rod body 22 is punched out at the inner diameter side portion 224 that faces the rim portion 104, interference with the rim portion 104 can be avoided.

  As described above, according to the present embodiment, the surface of the tie rod body 22 is curved so as to avoid the motor portion 11A and the steered wheels 101, so that a steered angle necessary for turning the vehicle can be ensured. . In addition, since the curved portion of the tie rod body 22 is thinner than other portions, a sufficient turning angle can be ensured. Further, the portion of the tie rod body 22 that is curved is wider in the vertical direction than the other portions, so that the cross-sectional area of the tie rod body 22 is secured to avoid a decrease in bending strength due to the bending. be able to.

  Further, according to the present embodiment, the tie rod main body 22 extends substantially in the vehicle width direction and has the female screw hole 221 for screwing with the male screw member 23 at its tip, so that the male screw member 23 and the tie rod tip member 24 are used. The outer portion of the tie rod 21 in the vehicle width direction can be formed of a plurality of members. Therefore, the straight male screw member 23 can be provided in the steering mechanism of the vehicle equipped with the in-wheel motor drive device that has many spatial restrictions and hardly includes the straight member. Moreover, the straight male screw member 23 can be installed using the inner space S of the load wheel 102.

  In other words, in the state shown in FIGS. 7 and 8, the tie rod tip member 24 and the male screw member 23 arranged on the outer side in the vehicle width direction of the tie rod 21 are located in the inner space region S. On the other hand, the end portion of the tie rod body 22 located on the inner side in the vehicle width direction of the tie rod 21 is located on the inner side in the vehicle width direction than the steered wheels 101. Thus, as will be described later, a device for increasing the ground height of the end portion of the tie rod body 22 is devised.

  In order to adjust the toe angle of the steered wheel 101, the length of the tie rod 21 may be changed. Specifically, the nuts 233 and 234 disposed on the outer side in the vehicle width direction of the tie rod 21 are loosened, and the grip portion 235 provided on the outer periphery of the center portion in the longitudinal direction of the male screw member 23 may be rotated. Compared with the prior art that rotates the adjusting bolt arranged on the inner side in the vehicle width direction, it is easier for the worker to reach and the adjustment work is easier. In addition, according to the present embodiment, the straight male screw member 23 can be made sufficiently long in the steering mechanism of the vehicle equipped with the in-wheel motor drive device with many spatial restrictions, so that the length adjustment allowance of the tie rod 21 is sufficiently secured. As a result, a sufficient adjustment margin of the toe angle can be secured (see FIG. 3). Further, according to the present embodiment, as shown in a cross section in FIG. 6, the grip portion 235 of the male screw member 23 is disposed directly below the tie rod tip member 24. Then, by rotating the grip portion 235 to one or the other, the distance between the tie rod body 22 and the tie rod tip member 24 is shortened (toe-in adjustment) by the action of the male screw portions of the one end portion 231 and the other end portion 232, or It becomes longer (toe out adjustment).

  In particular, in the present embodiment, the tie rod tip member 24 is connected to the ball joint portion 271 that is rotatably connected to the in-wheel motor drive device 11, the base portion 241 that extends from one end 242 to the other end 243, and the male screw member 23. And a projecting piece 246. The base 241 has a first surface 244 and a second surface 245 that extend from the one end 242 to the other end 243. A ball joint portion 271 is provided on one surface 244 near the one end 242. Further, a projecting piece 246 is provided on the other surface 245 near the other end 243. A female screw hole 247 is formed through the projecting piece 246, and the virtual axis P of the female screw hole 247 extends substantially parallel to one end of the base 241 on the other surface 245 side of the base 241. As a result, the male screw member 23 and the tie rod tip member 24 can be arranged in an overlapping manner, and the axial length of the male screw member 23 can be increased.

  Next, with reference to FIGS. 4 to 6, the vertical positional relationship of each component constituting the tie rod 21 will be described. The tie rod body 22 and the male screw member 23 extend in a substantially horizontal direction. When attention is paid to the lower edge of the tie rod body 22, the lower edge of the end portion is positioned higher than the lower edge of the tip portion. And the lower edge of the longitudinal direction center part of the tie rod main body 22 inclines and extends so that it may go down toward a front end side from a terminal end side. On the other hand, the upper edge of the tie rod body 22 is at the highest position in the central portion in the longitudinal direction, and extends so as to be inclined downward from the central portion in the longitudinal direction toward the distal side and the distal end side. The end portion of the tie rod body 22 has a circular cross section with the smallest vertical dimension, and the height of the upper edge and the lower edge is constant.

  The female screw hole 222 is disposed on the lower side of the distal end portion of the tie rod main body 22 and is positioned relatively below the female screw hole 221. This allows two configurations.

  1stly, it becomes possible to arrange | position the terminal part of the tie rod main body 22 in a position relatively higher than a front-end | tip part. As shown in FIG. 1, the end portion of the tie rod body 22 is located outside the inner space S and faces the road surface. According to this embodiment, the end portion of the tie rod body 22 is high between the end portion of the tie rod body 22 and the road surface. A sufficient distance in the vertical direction can be ensured.

  Secondly, the central axis of the female screw hole 222, the central axis of the female screw hole 247 formed in the protruding piece 246, and the central axis of the male screw member 23 constitute a common virtual axis P. In the present embodiment, the protruding piece 246 including the female screw hole 247 protrudes downward from the other surface 245 and the female screw hole 222 is disposed below the tie rod main body 22, so that the male screw member 23 is disposed below the tie rod 21. It becomes possible. Then, the height position of the ball joint 27 disposed on the upper side of the base portion 241 can be brought close to the height position of the female screw hole 221.

  Although the embodiments of the present invention have been described with reference to the drawings, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The steering mechanism of the vehicle equipped with the in-wheel motor drive device according to the present invention is advantageously used in electric vehicles and hybrid vehicles.

  11 in-wheel motor drive device, 11A motor section, 11B deceleration section, 11C hub section, 11N knuckle arm, 21 tie rod body, 22 tie rod body, 221, 222 female thread hole, 225 curved surface, 23 male thread member, 231 one end section, 232, etc. End, 233, 234 nut, 235 gripping part, 24 tie rod tip member, 241 base, 242 one end, 243 other end, 244 one side, 245 other side, 246 projecting piece, 247 female screw hole, 25 link, 25m tip, 254 Nut, 26, 27 Ball joint, 271 Ball joint part, 272 Ball part, 71 Steering gear box, 10 Steered wheels, 102 road wheel, 104 rim, L vehicle leftward turning direction, O axis, P imaginary axis, R vehicle rightward turning direction, S in an empty area.

Claims (8)

A tie rod that connects an in-wheel motor drive device mounted on a steerable wheel disposed on the outer side in the vehicle width direction and a steering gear box disposed on the inner side in the vehicle width direction,
The tie rod is
A tie rod main body that bends and extends between a distal end and a distal end, the distal end is rotatably connected to the steering gear box, and the distal end extends outward in the vehicle width direction;
A tie rod tip member rotatably connected to the in-wheel motor drive device;
A steering mechanism for a vehicle equipped with an in-wheel motor drive device, wherein one end side has a straight tie rod length adjusting member connected to the tip of the tie rod body and the other end connected to the tie rod tip member. The tie rod distal end member has a joint part rotatably connected to the in-wheel motor drive device, and one end and the other end extending from one end to the other end and extending from one end to the other end. One side of the base has a base provided with the joint portion, and a projecting piece provided on the other surface of the other end of the base,
The steering of a vehicle equipped with an in-wheel motor drive device according to claim 1, wherein the tie rod length adjusting member is connected to the projecting piece and extends substantially parallel to one end of the base on the other surface side of the base. mechanism.   The steered mechanism for a vehicle equipped with an in-wheel motor drive device according to claim 2, wherein a terminal portion of the tie rod body is positioned higher than a connecting portion between a tip of the tie rod body and the tie rod length adjusting member. The in-wheel motor drive device has a wheel hub portion, a speed reduction portion, and a motor portion having a larger diameter than the speed reduction portion, which are sequentially arranged from the outside in the vehicle width direction to the inside.
The tie rod tip member is connected to the outer periphery of the speed reduction part,
The turning mechanism of a vehicle equipped with an in-wheel motor drive device according to any one of claims 1 to 3, wherein the surface of the tie rod body is curved so as to avoid the motor unit.   The steering mechanism of a vehicle equipped with an in-wheel motor drive device according to any one of claims 1 to 4, wherein a surface of the tie rod body is curved so as to avoid a steered wheel driven by the in-wheel motor drive device. .   6. The turning mechanism of a vehicle equipped with an in-wheel motor drive device according to claim 4, wherein the tie rod body has a portion where the curve is formed thinner than other portions when viewed in the vertical direction.   The steering mechanism for a vehicle equipped with an in-wheel motor drive device according to claim 6, wherein the tie rod body has a portion where the curve is formed wider in the vertical direction than other portions. On the outer periphery of both ends of the tie rod length adjusting member, a female screw hole formed at the tip of the tie rod body and a male screw that is screwed into a female screw hole formed in the tie rod tip member are provided,
The steering mechanism for an in-wheel motor drive device-equipped vehicle according to any one of claims 1 to 7, wherein a grip portion that fits with a tool is provided on an outer periphery of a central portion of the tie rod length adjusting member.

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