JP2005199889A - Vehicle height adjustment device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent inclination of a vehicle body by synchronizing the operation of left and right vehicle height adjustment mechanisms with a simple structure. <P>SOLUTION: The device is constituted such that the left and right vehicle height adjustment mechanisms 23 for adjusting vehicle height by vertically moving an upper spring sheet 25 of a suspension spring 22 are connected to a common actuator 32 provided on a sub-frame 11 between left and right wheels 13 through left and right transmission mechanisms 41. Thereby, not only the number of parts can be reduced as compared with the case where actuators are provided on the left and right vehicle height adjustment mechanisms 23 respectively but also inclination of the vehicle body can be prevented by automatically and severely synchronizing the left and right vehicle height adjustment mechanisms 23. Particularly, since the vehicle height adjustment mechanism 23 is constituted by a ball screw mechanism 29 comprising a male member and a female member relatively rotatably thread-engaged, large out put can be generated by a compact structure. Further, since the transmission mechanism 41 transmits rotation of the actuator 32 to the ball screw mechanism 29 through an endless cable 35, the left and right transmission mechanisms 41 can be certainly interlocked with each other with a light weight structure. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a vehicle height adjustment device that adjusts a vehicle height by moving a spring seat of a suspension spring that suspends a suspension arm on a vehicle body by a vehicle height adjustment mechanism.

  In a suspension device in which a coil spring and a damper are arranged coaxially, a spring receiving member that supports the upper end of the coil spring is moved up and down by a ball screw mechanism driven by a motor to adjust the vehicle height. Is known.

Also, one end of each leaf spring that suspends the four wheels is supported on the vehicle body via a four-bar rotating shackle, and the vehicle height is adjusted by extending and retracting the four-bar rotating shackle with an electric wire winch Is known from Patent Document 2 below.
JP-A-11-108110 JP 2001-130234 A

  By the way, since the motor described in the above-mentioned patent document 1 is provided with the motor at the upper end of the suspension device, not only does the suspension device become larger and layout in a narrow wheelhouse becomes difficult, but also the left and right suspensions Since it is not the structure which synchronizes the motor of an apparatus, there existed a possibility that a vehicle body might incline during vehicle height adjustment. In addition, since the structure described in Patent Document 2 does not have a structure in which four electric winches for adjusting the vehicle height of the four wheels are operated in synchronization, the vehicle body is also inclined during the vehicle height adjustment. There was a possibility.

  The present invention has been made in view of the above circumstances, and an object thereof is to prevent the leaning of the vehicle body by synchronizing the operations of the left and right vehicle height adjustment mechanisms with a simple structure.

  To achieve the above object, according to the first aspect of the present invention, the vehicle height adjustment for adjusting the vehicle height by vertically moving the spring seat of the suspension spring for suspending the suspension arm on the vehicle body by the vehicle height adjustment mechanism. In the device, the vehicle height adjustment mechanism for the left and right wheels and the common actuator provided on the vehicle body between the left and right wheels are connected via the left and right transmission mechanisms, and the left and right vehicle height adjustment mechanisms are linked by the actuator. A vehicle height adjusting device characterized by driving is proposed.

  According to the invention described in claim 2, in addition to the structure of claim 1, the vehicle height adjusting mechanism is constituted by a male screw member and a female screw member that are screwed together so as to be relatively rotatable, and the transmission mechanism is an actuator. A vehicle height adjusting device is proposed in which the rotation is transmitted to the male screw member or the female screw member via an endless transmission member.

  The sub-frame 11 of the embodiment corresponds to the vehicle body of the present invention, the rear wheel 13 of the embodiment corresponds to the wheel of the present invention, the lower arm 16 of the embodiment corresponds to the suspension arm of the present invention, and The upper spring seat 25 corresponds to the spring seat of the present invention, and the endless cable 35 of the embodiment corresponds to the endless transmission member of the present invention.

  According to the configuration of the first aspect, the left and right vehicle height adjustment mechanisms for adjusting the vehicle height by moving the spring seat of the suspension spring up and down, and the left and right transmission mechanisms for the common actuator provided in the vehicle body between the left and right wheels. In addition to reducing the number of parts compared to installing actuators for the left and right vehicle height adjustment mechanisms, the left and right vehicle height adjustment mechanisms are automatically and strictly synchronized to prevent the vehicle from tilting. can do.

  According to the configuration of the second aspect, since the vehicle height adjusting mechanism is configured by the male screw member and the female screw member that are engaged with each other so as to be relatively rotatable, a large output can be generated with a compact structure, and the transmission mechanism can Since the rotation is transmitted to the male screw member or the female screw member via the endless transmission member, the left and right transmission mechanisms can be reliably interlocked with a lightweight structure.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 3 show a first embodiment of the present invention. FIG. 1 is an overall rear view of the vehicle height adjusting device (sectional view taken along line 1-1 in FIG. 2), and FIG. 2 is a two-way arrow in FIG. FIG. 3 is an enlarged view of the main part of FIG.

  As shown in FIGS. 1 to 3, left and right rear wheels are attached to a frame-like subframe 11 fixed to a main frame (not shown) at the rear of the vehicle body via double wishbone suspension devices 12 and 12. 13 and 13 are suspended. Each suspension device 12 includes a lower arm 16 and an upper arm 17 that are pivotally supported on the subframe 11 via joints 14 and 15 so as to be swingable up and down, and the distal ends thereof are joints 18 and 19. The left and right rear wheels 13 and 13 are rotatably supported on an axle 21 provided on a knuckle 20 pivotally supported via the wheel. The lower end of the suspension spring 22 is supported by a lower spring seat 16 a provided in the middle portion of the lower arm 16, and the upper end of the suspension spring 22 is supported by the subframe 11 via a vehicle height adjustment mechanism 23.

  The vehicle height adjusting mechanism 23 includes a cylindrical guide member 24 fixed to the lower surface of the subframe 11, and the suspension spring 22 is mounted on an upper spring seat 25 that is housed in the guide member 24 so as not to rotate but to move up and down. The upper end is supported. A male screw member 28 that is integrally formed with the upper spring seat 25 and extends upward is screwed into a female screw member 27 that is rotatably supported by the subframe 11 via a ball bearing 26. The female screw member 27 and the male screw member 28 constitute a ball screw mechanism 29. A driven pulley 30 is fixed to the upper end of the female screw member 27 protruding upward from the subframe 11, and the driven pulley 30 is covered with a cover 31 fixed to the upper surface of the subframe 11.

  A drive pulley 34 is fixed to an output shaft 33 that protrudes upward from an actuator 32 that is an electric motor provided at the center in the left-right direction of the subframe 11, and the drive pulley 34 and the left and right driven pulleys 30, 30 are a pair. The endless cables 35 and 35 are connected. The actuator 32 is provided with a lock mechanism (not shown), and turning on the lock mechanism restricts the rotation of the output shaft 33 due to an external force. A cover 36 covering the drive pulley 34 and covers 31, 31 covering the left and right driven pulleys 30, 30 are connected by guide pipes 37, 37, and endless cables 35, 35 are inside the guide pipes 37, 37. Stored. Thus, since the drive pulley 34, the driven pulleys 30 and 30, and the endless cables 35 and 35 are covered with the covers 31, 31, and 36 and the guide pipes 37 and 37, water and dust adhere to these members. Can be prevented.

  A pair of vehicle height sensors 38, 38 are provided between the left and right lower arms 16, 16 and the subframe 11, and an actuator 32 is provided by an electronic control unit U to which signals from these vehicle height sensors 38, 38 are input. Is controlled.

  Next, the operation of the embodiment having the above configuration will be described.

  When the sprung load of the vehicle increases, the suspension spring 22 contracts to lower the vehicle height, and when the vehicle height detected by at least one of the left and right vehicle height sensors 38, 38 falls below the lower limit value, a command from the electronic control unit U is issued. Thus, the actuator 32 rotates in one direction. As a result, the driving force of the actuator 32 rotates the female screw members 27, 27 of the ball screw mechanisms 29, 29 via the driving pulley 34, the left and right endless cables 35, 35 and the left and right driven pulleys 30, 30. , 27 and the upper spring seats 25, 25 integrated with the male screw members 28, 28 are lowered inside the guide members 24, 24, and the upper ends of the suspension springs 22, 22 are pushed down to increase the vehicle height. When the vehicle height detected by the high sensors 38, 38 exceeds the lower limit value, the actuator 32 stops.

  When the sprung load of the vehicle decreases, the suspension springs 22 and 22 extend to increase the vehicle height. When the vehicle height detected by at least one of the left and right vehicle height sensors 38 and 38 exceeds the upper limit value, the electronic control unit U In response to this command, the actuator 32 rotates in the other direction. As a result, the driving force of the actuator 32 rotates the female screw members 27 and 27 of the ball screw mechanism 29 and 29 via the driving pulley 34, the left and right endless cables 35 and 35, and the left and right driven pulleys 30 and 30, respectively. The upper spring seats 25, 25 integrated with the male screw members 28, 28 screwed to the 27, 27 are lifted inside the guide members 24, 24, and the upper ends of the suspension springs 22, 22 are released upward to reduce the vehicle height. When the vehicle height detected by the vehicle height sensors 38, 38 falls below the upper limit value, the actuator 32 stops.

  As described above, since the left and right vehicle height adjustment mechanisms 23, 23 are driven by the common actuator 32, the number of parts can be reduced compared to the case where the left and right vehicle height adjustment mechanisms 23, 23 are provided with dedicated actuators, respectively. In addition, the left and right vehicle height adjustment mechanisms 23, 23 can be automatically and strictly synchronized to prevent the vehicle body from being inclined during vehicle height adjustment. Further, since the vehicle height adjusting mechanisms 23, 23 are configured by the male screw members 28, 28 and the female screw members 27, 27 that are screwed together so as to be relatively rotatable, not only can a large output be generated with a compact structure, but also the transmission mechanism 41, Since 41 transmits the rotation of the actuator 32 to the female screw members 27 and 27 via the endless cables 35 and 35, the left and right transmission mechanisms 41 and 41 can be reliably interlocked with a lightweight structure. Further, since the actuator 32 is disposed between the left and right rear wheels 13, 13, it is not necessary to dispose the actuator 32 in a narrow wheel house, and the degree of freedom in layout can be increased.

  4 and 5 show a second embodiment of the present invention. FIG. 4 is an overall rear view of the vehicle height adjusting device, and FIG. 5 is a flowchart for explaining the operation.

  As shown in FIG. 4, in the second embodiment, a vehicle height setting switch 39 for setting a target vehicle height by the driver and a rotational position sensor 40 including a rotary encoder for detecting the rotational position of the actuator 32 are provided. The signal from the vehicle height setting switch 39 and the signal from the rotational position sensor 40 are input to the electronic control unit U. Other configurations of the second embodiment are the same as those of the first embodiment described above.

  In the flowchart of FIG. 5, first, the actual vehicle height is detected by the vehicle height sensors 38, 38 in step S1, and the actual vehicle height is converted into a corresponding actual motor rotation angle in step S2. In step S3, the target vehicle height set by the vehicle height setting switch 39 is converted into the target motor rotation angle. In step S4, the actual motor rotation angle is compared with the target motor rotation angle to calculate a deviation. In step S5, the deviation is calculated. A map search is made for the target drive current of the actuator 32 from the deviation. In step S6, the actuator 32 is driven with the target drive current, so that feedback control is performed so that the actual vehicle height matches the target vehicle height. As a result, when the deviation becomes 0 in step S7, the actuator 32 is stopped in step S8 and the vehicle height adjustment is finished.

  Thus, the second embodiment can achieve the same effects as the first embodiment described above.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention.

  For example, although endless cables 35 and 35 are used as endless transmission members in the embodiments, endless belts and endless chains can be used instead of endless cables 35 and 35.

  In the embodiment, the vehicle height adjusting mechanism for the left and right rear wheels 13, 13 has been described. However, the present invention can also be applied to the vehicle height adjusting mechanism for the left and right front wheels.

Overall rear view of the vehicle height adjusting apparatus according to the first embodiment (cross-sectional view taken along line 1-1 of FIG. 2) 2 direction view of FIG. 1 is an enlarged view of the main part of FIG. Overall rear view of vehicle height adjusting apparatus according to second embodiment Flow chart explaining operation

Explanation of symbols

11 Subframe (body)
13 Rear wheel
16 Lower arm (suspension arm)
22 Suspension spring 23 Vehicle height adjustment mechanism 25 Upper spring seat (spring seat)
27 Female Threaded Member 28 Male Threaded Member 32 Actuator 35 Endless Cable (Endless Transmission Member)
41 Transmission mechanism

Claims (2)

In a vehicle height adjustment device that adjusts the vehicle height by moving a spring seat (25) of a suspension spring (22) that suspends a suspension arm (16) on a vehicle body (11) by a vehicle height adjustment mechanism (23),
A vehicle height adjustment mechanism (23) of the left and right wheels (13) and a common actuator (32) provided on the vehicle body (11) between the left and right wheels (13) are connected via a left and right transmission mechanism (41). The vehicle height adjusting device is characterized in that the actuator (32) drives the left and right vehicle height adjusting mechanisms (23) in conjunction with each other. The vehicle height adjusting mechanism (23) includes a male screw member (28) and a female screw member (27) that are screwed together so as to be relatively rotatable, and the transmission mechanism (41) rotates the actuator (32) with an endless transmission member (35). The vehicle height adjusting device according to claim 1, wherein the vehicle height adjusting device is transmitted to the male screw member (28) or the female screw member (27).

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