JP3038243U - Steering device for transporter in the field - Google Patents

Abstract

(57) Abstract: In a steering device attached to a field transporter, a driving feeling is improved as compared with a conventional steering device, and a minimum turning radius is made smaller than that of the conventional steering device. A front axle 5 having front wheels 3, 3 is attached to a body frame so as to be rotatable about a vertical axis 64. A mounting tool 62 is provided at an eccentric position with respect to the turning center of the front axle 5. The rotating shaft 27 that rotates in conjunction with the steering wheel and the fixture 62 are connected by the steering gear box 20. The steering gear box 20 has a rotating shaft 27.
And a rack that meshes with the pinion, and one end of the rack is connected to the fixture 62.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 This invention relates to a steering device for an in-field carrier.

[0002]

[Prior art]

 9 to 11 show a conventional steering device used in an in-field transporter. The above-mentioned in-field carrier adopting this steering device has a front frame 81 and a rear frame 85 which are connected via a vertical pin 71, and the front frame 81 has the front wheels 82 and 82 and the rear frame. The rear wheels 86, 86 are provided on 85, respectively. Then, in the steering device, the right or left rotation operation R, L of the rotary shaft 73 connected to the steering handle 72 shown in FIG. 9 is controlled by the front link 82, 82 via the multiple link mechanism 73. Of the connecting link 74 branched from the multiple link mechanism 73 to the push-pull operation in the pull-in direction or the push-out direction. The push-pull operation of the front frame 81 causes the front frame 81 to swing around the vertical pin 71. Note that FIG. 10 shows the state of the multiple link mechanism 73 and the like when traveling straight, and FIG. 11 shows the state of the multiple link mechanism 73 and the like when turning right.

[0003]

[Problems to be solved by the device]

 The conventional steering device for an in-field transporter described above is adapted to perform the swinging motion of the front frame 81 with the vertical pin 71 as a fulcrum and the conversion motion of the front wheels 82, 82 to the right or left. Although it has an advantage that the minimum turning radius can be reduced, the maneuverability for the driver who operates the steering wheel 72 is different from that of a passenger car, and thus the maneuverability is uncomfortable.

The present invention has been made in view of the above circumstances, and has an improved driving feeling as compared with a conventional steering device, and has a minimum turning radius that can be made smaller than a conventional steering device. It aims at providing the steering device of. Another object of the present invention is to provide a steering device for an in-field transporter, which simplifies the frame structure and makes it easy to reduce costs.

[0005]

[Means for Solving the Problems]

 In the steering device for a width-directed carrier according to the present invention, the longitudinal central portion of the front axle to which the front wheels are attached is attached to the body frame so as to be able to turn about the vertical axis, and the attachment provided on the front axle is , The front axle is located at an eccentric position with respect to the turning center, and is rotated in conjunction with the steering handle by operating the steering handle. The rotating shaft and the above-described fixture linearly extend and contract the rotating motion of the rotating shaft. In addition to being linked by a motion conversion mechanism, one of the extension motion and contraction motion of the motion conversion mechanism corresponds to the clockwise rotation motion of the rotary shaft, and the other motion corresponds to the above motion. Corresponding to the counterclockwise rotation of the rotating shaft, the motion conversion mechanism engages the pinion provided on the rotating shaft and the pinion so that one end can swing relative to the fixture. A steering gear box including a connected rack and a housing that accommodates the pinion and the rack and that is horizontally swingably attached to the body frame on the rotation axis of the rotation axis around the rotation axis. It has been done.

In this steering apparatus, when the rotating shaft is rotated clockwise by the rotating operation of the steering handle, the motion conversion mechanism contracts, and conversely, when the rotating shaft is rotated counterclockwise by the rotating operation of the steering handle. The motion conversion mechanism is designed to expand, and the contraction of the motion conversion mechanism causes the front axle to turn right, and the expansion of the motion conversion mechanism causes the front axle to rotate left. .

When the rotary shaft is rotated clockwise by the rotating operation of the steering wheel, the pinion rotates and the rack retracts, whereby the motion conversion mechanism contracts, and the contraction displaces the fixture to move the front axle. Since it is turned right, the left and right front wheels turn right around the vertical axis together with the front axle, and the field transporter turns right. On the contrary, when the rotating shaft is rotated counterclockwise by the turning operation of the steering wheel, the pinion rotates and the rack advances and the motion conversion mechanism expands. Is turned left, the left and right front wheels turn left around the vertical axis together with the front axle, and the in-field carrier turns left. Also, when the axle turns right or left, the housing of the steering gear box swings around the axis of rotation of the rotating shaft with respect to the body frame, and at the same time, one end of the rack of the steering gear box and the fixture are Oscillates relative to each other.

In such a steering apparatus, the front axle and the shaft body that supports the front axle on the vehicle body frame so as to be able to turn about the vertical axis are in the front-back direction that intersects the vertical axis. It is possible to adopt a configuration in which the vehicle body frame is swingably mounted around a horizontal axis, and with such a structure, when the in-field transporter travels in the field, the unevenness of the field is in front. Since it is absorbed by the swing of the wheels and front axle, the vibration due to the unevenness is not transmitted to the body frame so much.

[0009]

[Embodiment of the invention]

 FIG. 1 is a plan view for explaining the layout of a steering device 2 and the like for a vehicle body frame 1 of an intra-field transporter, and FIG. 2 shows a steering device 2 according to one embodiment of the present invention when the intra-field transporter is in a straight state. Fig. 3 is a schematic plan view showing the main part, Fig. 3 is a schematic plan view showing the main part of the steering device 2 when the intra-field transporter is in the left-turning state, and Fig. 4 is the steering device when the intra-field transporter is in the right-turning state. 2 is a schematic plan view showing the main part of FIG. 2, FIG. 5 is a rear view for explaining the mounting structure of the front axle 5 and the horizontal shaft 40 to the vehicle body frame 1, and FIG. 6 is a plan view of the steering ring gearbox 20. 8 is a partially cutaway side view of the steering gear box 20, and FIG. 8 is a schematic enlarged sectional view taken along the line VII-VII of FIG.

As shown in FIG. 1, the body frame 1 is divided into a front section F and a rear section R, and a driver's seat 11 and a steering wheel (not shown) are provided in the front section F. Further, the steering device 2 is provided below the front section F of the body frame 1. 3 is a front wheel and 4 is a rear wheel.

As shown in FIGS. 2 to 5, left and right wheels 3, 3 are attached to both ends of the front axle 5, and a shaft body 6 is fixed to the center of the front axle 5 in the longitudinal direction. A bracket 61 is provided on the shaft body 6 so as to project leftward when viewed from the front side, and a mounting tool 62 is provided at the tip of the bracket 61. The shaft body 6 is attached to the vehicle body frame 1 so as to be rotatable about a vertical axis 64 (a vertical line passing through the center of the protrusion 63) via a protrusion 63. Therefore, as shown in FIG. 5, the fixture 62 is arranged at a position eccentric by S with respect to the turning center of the front axle 5 (which coincides with the vertical axis 64).

2 to 4, reference numeral 20 denotes a steering gear box, and the details of the steering pen box 20 are shown in FIGS. 6 to 8. The steering gear box 20 has a long cylindrical housing 21, and a pinion 23 and a pinion 23 thereof are housed in a bearing box 22 provided at an intermediate portion of the housing 21 in the longitudinal direction, as shown in FIG. The rack 24, which meshes with the rack 24, is housed therein, and the force of the spring 25 causes the rack 24 to be constantly pressed against the pinion 23 side via the pressing body 26 so that the two can be reliably meshed. .

The pinion 23 shown in FIG. 8 is provided concentrically at the lower end of a rotary shaft 27 that is rotated by operating a steering handle (not shown) in conjunction with the steering handle. Further, the rack 24 extends through the housing 21 and projects from the housing 21, and a tip end tool 29 is attached to one end 28 of the rack 24. A flexible protective tube 31 is provided between the end of the housing 21 and the tip 29. The steering gear box described here constitutes a motion conversion mechanism that converts the rotational motion of the rotary shaft 27 into a linear expansion / contraction motion.

The housing 21 of the steering gear box 20 is rotated by a known coupling mechanism (not shown) on the body frame 1 on the rotation axis 32 of the rotation shaft 27 shown in FIGS. It is attached so as to be horizontally swingable around the axis 32. Further, one end portion 28 of the rack 24 is connected to the mounting tool 62 via the tip tool 29 and the tie rod 33 shown in FIGS. In this embodiment, the extension operation of the steering gear box 20 corresponds to the clockwise rotation operation of the rotary shaft 27, and the contraction operation corresponds to the counterclockwise rotation operation of the rotary shaft 27.

On the other hand, the front axle 5 and the shaft 6 that supports the front axle 5 on the vehicle body frame 1 so as to be pivotable around the vertical axis 64 are the same as the vertical axis 64 shown in FIG. It is attached to the body frame 1 so as to be swingable around a horizontal axis 41 in the front-rear direction that intersects. That is, as can be inferred from FIG. 5, the horizontal shaft 40 having the horizontal axis 41 is attached to the vehicle body frame 1 shown in FIG. 1 via a known bearing mechanism (not shown).

In the in-field transporter that employs the steering apparatus 2 described above, when the rotating shaft 27 is rotated clockwise by the rotating operation of the steering wheel, the pinion 23 of the steering gear box 20 rotates and the rack 24 retracts. As a result, the steering ring gearbox 20 contracts as shown by arrow a in FIG. 4, and the contraction causes the fixture 62 to be displaced and the front axle 5 to turn right as shown in FIG. 3, 3 and the front axle 5 turn right around the vertical axis 64, and the in-field carrier turns right. On the contrary, when the rotary shaft 67 is rotated counterclockwise by the rotating operation of the steering wheel, the pinion 23 rotates and the rack 24 advances, so that the steering gear box 20 is indicated by the arrow b in FIG. And the front wheel axles 3 are rotated leftward as shown in FIG. 3, so that the left and right front wheels 3, 3 together with the front axle wheel 5 rotate leftward about the vertical axis 64. Turn and the in-field carrier turns left. When the front axle 5 turns right or left, the housing 21 of the steering gear box 20 swings around the rotation axis 32 of the rotation shaft 27 with respect to the body frame 1, and at the same time, the steering gear box 20 moves. One end 28 of the rack 24, the tie rod 33, and the fixture 62 swing relative to each other.

This in-field transporter is often run forward or backward in a field with uneven ground, and if the unevenness of the ground is directly transmitted to the vehicle body frame 1, maneuverability is degraded. However, in the steering device 2, the front axle 5 and the six bodies that support the front axle 5 on the vehicle body frame 1 so as to be pivotable about the vertical axis 64 are horizontal as described in FIG. Since it is attached to the body frame 1 so as to be swingable around the horizontal axis 41 in the front-rear direction via the shaft 40, when the intra-field transporter travels in the field, the unevenness of the field causes the front wheels 3, 3 and Since it is absorbed by the swing swing of the front axle 5, the vibration due to the unevenness is not so much transmitted to the body frame 1.

[0018]

[Effect of the invention]

 According to this invention, when the steering handle is operated to rotate the rotary shaft to the left or right, the rotary motion of the rotary shaft is changed by the linear expansion and contraction motion of the steering gear box using the pinion and the rack. Since it is converted into a turning motion and the field vehicle is turned only by such a turning motion of the front axle, a driving sensation much like that of a passenger car for general road use can be obtained. Also, since there is a large degree of freedom in selecting the eccentricity amount and the eccentric direction with respect to the front axle turning center of the mounting position of the housing of the steering gear box to the vehicle body frame and the mounting device to which one end of the rack is mounted, It is easy to make the minimum turning radius of the field transporter smaller than the conventional one. Further, since it is not necessary to use a multiple link mechanism or a connecting link having a complicated structure unlike the conventional steering device, the structure of the steering device is simplified, and the cost reduction can be easily achieved.

Further, the front axle and the shaft body that supports the front axle on the body frame so as to be pivotable about a vertical axis are swingable about a horizontal axis in the front-rear direction intersecting the vertical axis. By adopting the configuration of being attached to the body frame, the swing of the body frame due to the unevenness of the field when the intra-field transporter travels in the field is absorbed by the swing of the front axle. As such, it helps to bring the driving sensation of the carrier closer to that of a passenger car.

[Brief description of the drawings]

FIG. 1 is a plan view for explaining a layout of a steering device and the like for a body frame of an in-field transport machine.

FIG. 2 is a schematic plan view showing a main part of the steering device according to the embodiment of the present invention when the in-field carrier is in a straight-ahead state.

FIG. 3 is a schematic plan view showing a main part of the steering device when the in-field transport machine is turning left.

FIG. 4 is a schematic plan view showing a main part of the steering device of the present invention when the in-field carrier is in a right-turning state.

FIG. 5 is a rear view for explaining the mounting structure of the front axle and the shaft body to the vehicle body frame.

FIG. 6 is a plan view of the steering gear box.

FIG. 7 is a partially cutaway side view of the steering gear box.

8 is a schematic enlarged cross-sectional view taken along the line CC of FIG.

FIG. 9 is a partially cutaway side view showing a steering wheel and a rotary shaft of a conventional steering device.

FIG. 10 is a schematic plan view showing a straight traveling state of an intra-field transporter that employs a conventional steering device.

FIG. 11 is a schematic plan view showing a right turning state of an intra-field transporter that employs a conventional steering device.

[Explanation of symbols]

 1 Body Frame 2 Steering Device 3 Front Wheel 5 Front Axle 20 Steering Gear Box (Motion Conversion Mechanism) 21 Housing 23 Pinion 24 Rack 27 Rotating Shaft 32 Rotating Shaft Rotating Axis 41 Horizontal Axis 62 Fixing Tool 64 Vertical Axis

Claims (2)

[Utility model registration claims] 1. A front axle to which front wheels are attached is attached to a vehicle body frame so as to be able to turn about a vertical axis, and a fixture provided on the front axle is eccentric with respect to a turning center of the front axle. The rotary shaft, which is disposed at a location and is rotated by interlocking with the steering handle by operating the steering handle, and the attachment are connected by a motion conversion mechanism that converts the rotational motion of the rotary shaft into a linear expansion / contraction motion. In addition, either one of the extension operation and the contraction operation of the motion conversion mechanism corresponds to the clockwise rotation operation of the rotation shaft, and the other operation corresponds to the counterclockwise rotation operation of the rotation shaft. The motion converting mechanism includes a pinion provided on the rotary shaft, a rack that meshes with the pinion and one end of which is connected to the fixture so as to be capable of relative swing, and those pinions. The steering gear box is provided with a housing that accommodates an on-rack and a rack and that is mounted on the rotation axis of the rotation shaft so as to be horizontally swingable around the rotation axis of the body frame. Steering device for field transporter. 2. The front axle and a shaft body that supports the front axle on the body frame so as to be pivotable about the vertical axis are swingable about a horizontal axis in the front-rear direction intersecting the vertical axis. The steering device for an intra-field transporter according to claim 1, wherein the steering device is attached to the vehicle body frame.