JP2011148394A - Travelling device of large-sized conveying vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide the travelling device of a large-sized conveying vehicle in which a steering angle of a tire is increased with a simple structure. <P>SOLUTION: The travelling device 12 of the large-sized conveying vehicle includes a travelling mechanism having a tire 21 rotatable via a travelling motor 26 or an axle 25, a lifting mechanism that moves the travelling mechanism up and down relative to a vehicle body by using an actuator 24, and a steering mechanism that rotates a rotary bracket 22 rotatably supporting the travelling mechanism and the lifting mechanism. The steering mechanism includes a bearing 31 fixed to the rotary bracket 22 on the side close to an outer wheel 311 and fixed to a vehicle body side on the side close to an inner wheel 312 for transmitting rotation of a steering motor via a worm gear 32 to the outer wheel 311 of the bearing 31. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a traveling device for a large transport vehicle such as a carrier for carrying a heavy object, and more particularly to a traveling device having a steering mechanism that increases the steering angle of a tire with a simple configuration.

  A large transport vehicle such as a carrier is used at a work site for transporting large heavy objects such as bridge construction. Such a large transport vehicle can swing a double-wheeled traveling device at the bottom of a long vehicle body serving as a loading platform, that is, an axle having pneumatic tires at both ends of an axle in a direction perpendicular to the axle by a swing arm. A plurality of traveling devices are provided. For example, Patent Document 1 below discloses an example of such a traveling device, and FIG. 5 is a plan view of the traveling device described in the same document.

  This traveling device 100 has a rotating frame 120 that can be rotated by a bearing 110 with respect to a vehicle body 200, and a differential gear or the like is provided at the lower part of the rotating frame 120, through which the output of the traveling motor 130 is changed. It is transmitted to the tire 150. The bearing 110 has a rotating frame 120 fixed to the inner ring 111 and is attached to the outer ring 112 on the vehicle body 200 side via a mounting plate 115 or the like. A semicircular steering gear 160 is fixed to the opposite side of the mounting plate 115, and the rotation output of the steering motor 170 is transmitted to the steering gear 160 via the transmission gear 175 so that the tire 150 is steered.

Japanese Patent No. 3407430

  By the way, the traveling device provided in such a large transport vehicle has various structures in a narrow space, and one of the problems is how to configure the steering mechanism. In the conventional traveling device 100 shown in FIG. 5, the transmission gear 175 fixed to the output shaft of the steering motor 170 and the steering gear 160 fixed to the bearing 110 are constituted by spur gears. Therefore, the steering motor 170 provided with the transmission gear 175 has the same height as the tire 150 because the rotation axis thereof is the vehicle body vertical direction (the direction through the drawing).

  Thus, in the conventional traveling device 100, when the tire 150 is tilted by steering, the tire 150 is attached to a space portion that does not interfere. However, in such a steering mechanism, the steering angle of the tire 150 is about 155 ° by the steering motor 170. It was limited and not enough. For example, a carrier used for erection of a bridge may carry a bridge girder and transport a road that is not wide enough. However, since the steering angle is small at that time, it must be turned over many times. It may not be possible. At this time, the installation of a bridge girder weighing hundreds of tons damaged the road and sometimes made holes.

  On the other hand, as a steering mechanism that does not interfere with the tire 21, there are a structure in which a cylinder is steered by a link as a driving current, and a structure in which the cylinder is steered by using a rack and pinion as a driving source. However, in both cases, the structure is complicated and the steering angle is limited by the stroke of the cylinder.

  Therefore, an object of the present invention is to provide a traveling device for a large transport vehicle in which the steering angle of a tire is increased with a simple configuration in order to solve the above-described problem.

  A traveling device for a large transport vehicle according to the present invention includes a traveling mechanism including a tire that can rotate via a traveling motor or an axle, an elevating mechanism that moves the traveling mechanism up and down with respect to a vehicle body using an actuator, A steering mechanism that rotates a rotating bracket that rotatably supports a traveling mechanism and the elevating mechanism, the steering mechanism having an outer ring side fixed to the rotating bracket and an inner ring side fixed to the vehicle body side A bearing is provided, and the rotation of the steering motor is transmitted to the outer ring of the bearing via a worm gear.

In the traveling device for a large transport vehicle according to the present invention, the outer ring of the bearing is formed with worm wheel teeth forming one of the worm gears on the outer peripheral side, and the other worm meshing with the worm wheel is rotated. The steering motor to be applied is preferably a hydraulic motor.
In the traveling device for a large transport vehicle according to the present invention, a rotation detecting means for detecting the rotation of the worm is provided on the rotation shaft of the worm with respect to the control device for controlling the rotation of the steering motor. Is preferred.

  According to the present invention, since the rotation of the steering motor that steers the tire via the bearing is transmitted using the worm gear whose two axes are perpendicular to each other, the height of the bearing that does not interfere the steering motor with the tire. It is possible to provide a traveling device for a large transport vehicle that is arranged in a large configuration and has a simple structure and a large steering angle.

It is the top view which showed the carrier. It is the side view which showed the carrier. It is the enlarged view which showed the traveling apparatus for one machine shown in FIG. 1 is a plan view conceptually showing an embodiment of a steering mechanism. It is the top view which showed the traveling apparatus comprised with the conventional steering mechanism.

  Next, an embodiment of a traveling device for a large transport vehicle according to the present invention will be described below with reference to the drawings. In the present embodiment, a steering mechanism of a traveling device that constitutes a carrier will be described. 1 and 2 are a plan view and a side view showing the carrier. A driver's cab and a power unit (not shown) are attached to the carrier 10, and traveling and steering are possible by interlocking a plurality of traveling devices 12 with a computer.

  The traveling device 12 includes four tires 21 in total, two on each of the left and right sides. A swing arm 23 that can swing in the vertical direction is provided to a suspension bracket 22 that steers the tire 21. A lifting mechanism supported by the hydraulic cylinder 24 is configured. In addition, the traveling device 12 includes a traveling mechanism that rotates the axle by a traveling motor, and a steering mechanism that steers the tire 21 via the suspension bracket 22 by a steering motor. The suspension bracket 22 is a “rotating bracket” described in the claims.

  FIG. 3 is an enlarged view showing the traveling device 12 for one aircraft shown in FIG. As described above, the elevating mechanism of the traveling device 12 is such that the swing arm 23 is swingably connected to the suspension bracket 22 in the vertical direction, and the swing arm 23 adjusts the distance between the tire 21 and the vehicle body 11 by the expansion and contraction of the hydraulic cylinder 24. It can be done. Therefore, the carrier 10 can travel while the swing arm 23 moves up and down in accordance with the unevenness of the travel path, and the height of the vehicle body 11 is constant. In the traveling mechanism, an axle 25 is provided at the tip of the swing arm 23, and the rotational output of the traveling motor (hydraulic motor) 26 is transmitted to the axle via the differential gear, so that the traveling control of the carrier 10 is possible.

  In the traveling device 12 of the present embodiment, a steering mechanism configured to transmit the rotation output of the steering motor to the suspension bracket 22 using a worm gear is provided. The suspension bracket 22 has a rotating plate 22a on the upper surface fixed to the outer ring 311 of the bearing 31, and the inner ring 312 of the bearing 31 is fixed to the body frame 33 side. Accordingly, the tire 21 provided via the suspension bracket 22 can be steered with respect to the vehicle body 11 via the bearing 31.

  Here, FIG. 4 is a plan view conceptually showing the steering mechanism of the present embodiment. The outer ring 311 of the bearing 31 is formed with one tooth of a worm wheel 321 forming one of the worm gears 32 on the outer peripheral side thereof. And the other worm 322 is provided with respect to the worm wheel 321, and the teeth of each other mesh with each other. The worm 322 is integrated with the rotating shaft 34, and a steering motor (hydraulic motor) 35 that outputs rotation is coupled to the rotating shaft 34. A potentiometer 36 for detecting rotation is attached to the rotating shaft 34 on the opposite side of the steering motor 35.

  The worm gear 32 is a gear in which a worm wheel 321 and a worm 322 are engaged with each other with two axes at right angles. Therefore, the worm 322 is disposed in the horizontal direction with respect to the vehicle body 11, and the steering motor 35 is disposed at the same height as the worm gear 32 above the tire 21. In the present embodiment, a hydraulic motor is used as the steering motor 35, and since the hydraulic motor is a small motor that can output the necessary torque, it is in the traveling device 12 with limited space, The arrangement is possible without interfering with the steering tire 21.

  A control device 41 is connected to the potentiometer 36 that detects the rotation angle of the worm 322, and the control device 41 controls the operation of a fluid device such as a hydraulic pump or a switching valve that drives the steering motor 35 or the like. It is connected to a driving device 42 comprising the fluid device. The traveling device 12 is configured to feed back a detection signal from the potentiometer 36 to control the steering angle of the tire 21.

  The carrier 10 having such a traveling device 12 is moved forward and backward to rotate the tire 21 by transmitting the rotational output to the axle via the differential gear by driving the traveling motor 26. During such travel, the steering motor 35 is rotated by the hydraulic energy of the hydraulic fluid supplied from the drive device 42 in response to a control signal from the control device 41. Then, the worm 322 integrated with the rotating shaft 34 rotates, and further, the meshed worm wheel 321 rotates, whereby the suspension bracket 22 fixed to the outer ring 311 of the bearing 31 rotates by a predetermined amount, and the tire 21 is steered. Done.

  The rotation angle of the suspension bracket 22, that is, the steering angle of the tire 21 is detected by the potentiometer 36, and the detected value is sent to the control device 41 and calculated by arithmetic processing. Based on the steering angle data obtained in this way, the control device 41 further transmits a control signal to the drive device 42 to steer the tire 21 at an appropriate angle.

  According to the traveling apparatus for a large transport vehicle according to the present embodiment, the worm gear 32 (worm wheel 321 and worm 322) whose two axes are perpendicular to each other is used in a simple configuration, and the steering motor 35 is higher than the tire 21. There is no interference during steering because the positions are different. In addition, since the installation position of the steering motor 35 is increased and the drive source is reduced in size using a hydraulic motor, a compact steering mechanism can be provided for the traveling device 12 in a small space. In addition, since the steering motor 35 does not interfere with the steering of the tire 21, a steering angle of about 270 ° can be obtained, and it is possible to move by skewing or turning even in a narrow place, and there is no need to perform a conventional stationary. Problems such as damaging the road can be solved. Furthermore, the tire 21 can be accurately steered by feedback control using the potentiometer 36.

As mentioned above, although the traveling apparatus of the large sized conveyance vehicle concerning this invention was demonstrated, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
For example, in the embodiment, a hydraulic motor is used as the steering motor 35, but an electric motor may be used.
In the above embodiment, the outer ring 311 of the bearing 31 is formed with the teeth of the worm wheel 321 forming one of the worm gears 32. However, the outer ring 311 and the worm wheel 321 may be separate. .

DESCRIPTION OF SYMBOLS 10 Carrier 11 Car body 12 Running device 21 Tire 22 Suspension bracket 23 Swing arm 25 Axle 26 Running motor 31 Bearing 32 Worm gear 321 Worm wheel 322 Worm 34 Rotating shaft 35 Steering motor 36 Potentiometer 41 Control device 42 Drive device

Claims (3)

A travel mechanism including a tire that can rotate via a travel motor and an axle, an elevating mechanism that moves the travel mechanism up and down with respect to the vehicle body using an actuator, and the travel mechanism and the elevating mechanism are rotatably supported. In a traveling device for a large transport vehicle having a steering mechanism for rotating a rotating bracket
The steering mechanism includes a bearing having an outer ring side fixed to the rotating bracket and an inner ring side fixed to the vehicle body side, and transmits the rotation of the steering motor to the outer ring of the bearing via a worm gear. There is a traveling device for a large transport vehicle. In the traveling apparatus for a large transport vehicle according to claim 1,
The outer ring of the bearing is formed with worm wheel teeth forming one of the worm gears on the outer peripheral side thereof, and the steering motor for applying rotation to the other worm meshing with the worm wheel is a hydraulic motor. A traveling device for a large transport vehicle. In the traveling device for a large transport vehicle according to claim 2,
A traveling device for a large transport vehicle, wherein a rotation detecting means for detecting rotation of the worm is provided on a rotating shaft of the worm with respect to a control device for controlling rotation of the steering motor.

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