JPH08164726A - Suspension link mechanism of reach type fork lift - Google Patents

Abstract

PURPOSE: To attain an easy assembling with a simplified structure and reduce the manufacturing costs, and also improve the serviceability. CONSTITUTION: A drive suspension 14 being energized downward by a wheel pressure regulating spring 12 while supporting a drive unit 5 is connected turnably to one end of a swinging link 16 mounted swingably on a vehicle body frame 17. A guide roller 21 mounted on the suspension 14 is engaged with a guide rail 22 fixed to the frame 17. In this way the up and down movement is guided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension link mechanism for a reach type forklift, and more particularly to a suspension link mechanism for automatic drive tire pressure adjustment of a four wheel type reach type forklift.

[0002]

2. Description of the Related Art A conventional suspension link mechanism for a four-wheel reach type forklift truck is shown in FIGS. A drive tire 1 and caster tires 2 are provided on the rear portion of the vehicle body. The drive tire 1 is connected to a motor 4 via a drive unit gear 3, and these constitute a drive unit 5. The drive unit 5 is supported by a drive unit suspension 6, and the drive unit suspension 6 constitutes a parallel link together with the upper link 7 and the lower link 8 and is attached so as to be vertically movable. The lower link 8 is swingably provided around a shaft 9 fixed to the vehicle body frame, and is also rotatable with a lower end portion of the drive unit suspension 6 by a shaft 10. Further, the caster tire 2 is attached to the lower link 8 via the caster link 11. One end of the drive unit suspension 6 is constantly urged downward by a wheel pressure adjusting spring 12 fixed to a vehicle body frame via a spring adjuster 13.

The rear wheel load is applied to the lower link 8 via the shaft 9 which is the center of swing, and then the shafts 9 and 10
Link length L1 between, shaft 9 and caster tire 2
The tire is divided into the drive tire 1 and the caster tire 2 in accordance with the ratio of the link length L2 to the mounting position.
Furthermore, the weight of the drive unit 5 and the spring force of the wheel pressure adjusting spring 12 are also applied to the drive tire 1, and the machine base can run due to the frictional force with the ground. Even if the drive tire 1 wears to some extent as the vehicle travels, the wheel pressure adjusting spring 12 constantly urges the drive unit suspension 6 downward. Therefore, the drive unit 5 is pushed down by the amount of wear of the drive tire 1 to a predetermined wheel pressure. It is possible to drive while securing. Further, when the drive tire 1 is worn to a predetermined value or more, the wheel pressure adjusting spring 12 expands and the wheel pressure decreases, so that the mounting height of the spring 12 is adjusted by the spring adjuster 13 so that the required wheel pressure is obtained. Is configured to ensure.

A conventional suspension link mechanism for a reach type forklift truck, which has a parallel link as described above and moves a drive unit up and down, is disclosed in, for example, Japanese Patent Laid-Open No. 4-36.
It is disclosed in Japanese Patent Publication No. 1997, Japanese Utility Model Publication No. 52-46417, and the like.

[0005]

However, in the conventional suspension link mechanism, since it is necessary to push down the drive unit 5, the drive unit suspension 6, the upper link 7 and the lower link 8 form a parallel link. Therefore, the structure of the link mechanism is complicated, the number of parts is large, and it takes a lot of time and labor for assembling, and the manufacturing cost is high. Furthermore, since the number of rotating parts in the link mechanism is large, there are also many greasing points, and serviceability is poor.

The present invention has been made in order to solve the above problems, and provides a reach type forklift truck which has a simple structure, can be easily assembled, can reduce the manufacturing cost, and is excellent in serviceability. An object is to provide a suspension link mechanism.

[0007]

A suspension link mechanism for a reach type forklift according to the present invention includes a swing link which is swingably provided on a frame of a vehicle body and which supports driven wheels, and a swing link which is rotatable on the swing link. A drive unit suspension that supports the drive unit that drives the drive wheels and that is connected to the guide roller; a guide roller that is provided on the drive unit suspension; a guide rail that is fixed to the frame of the vehicle body and guides the vertical movement of the guide roller; On the other hand, a wheel pressure adjusting spring for urging the drive unit suspension downward is provided.

[0008]

In the present invention, the vertical movement of the drive unit suspension that supports the drive unit is guided by the guide roller and the guide rail. As a result, the upper link used in the conventional suspension link mechanism becomes unnecessary, and the structure is simplified and the number of pivot points is reduced.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a suspension link mechanism of a reach type forklift according to an embodiment of the present invention. 2 is an exploded perspective view of the suspension link mechanism shown in FIG. Drive tire 1 that will be the driving wheel at the rear of the vehicle
And a caster tire 19 which is a driven wheel. The drive tire 1 is connected to a motor 4 via a drive unit gear 3, and these constitute a drive unit 5. The drive unit 5 is rotatably supported by the drive unit suspension 14, and the lower end of the drive unit suspension 14 is rotatably connected to one end of a swing link 16 via a shaft 15. A shaft 18 fixed to the body frame 17 penetrates through the center of the swing link 16, and the swing link 16 is swingably provided with respect to the body frame 17 by the shaft 18. A caster unit 20 with a suspension having caster tires 19 is attached to the other end of the swing link 16.

Guide rollers 21 are rotatably attached to both sides of the drive unit suspension 14, and a pair of guide rails 22 for guiding the vertical movements of these guide rollers 21 are reinforced by a reinforcing plate 23. It is fixed to. As shown in FIG. 3, the guide rail 22 has a U-shaped cross-sectional shape, and the guide roller 21 rotatably provided on the side portion of the drive unit suspension 14 via a bearing 25 is provided inside the guide rail 22. Is located in. A part of the outer peripheral surface of the guide roller 21 comes into close contact with the guide rail 22, and the drive unit suspension 14 can move vertically along the guide rail 22 while the guide roller 21 rotates.

A bracket 24 is fixed to the vehicle body frame, one end of the wheel pressure adjusting spring 12 is attached to the bracket 24 via a spring adjuster 13, and the other end of the wheel pressure adjusting spring 12 is an upper portion of the drive unit suspension 14. Is attached to. The wheel pressure adjusting spring 12 constantly urges the drive unit suspension 14 downward.

Next, the operation of this embodiment will be described. Reach type forklift rear wheel load is shaft 18
After joining the swing link 16 via the
Link length between shafts 18 and 15 of
According to the ratio of the link length between the mounting position of the caster unit 20 and the caster unit 20, the drive tire 1 and the caster tire 19 are divided. Furthermore, the weight of the drive unit 5 and the spring force of the wheel pressure adjusting spring 12 are also applied to the drive tire 1, and the machine base can travel due to the frictional force with the ground.

Since the drive unit suspension 14 is constantly urged downward by the spring force of the wheel pressure adjusting spring 12, when the rear wheel load decreases due to reaching by loading a fork (not shown), or when the vehicle travels. When the drive tire 1 is worn or the like, the guide roller 21 moves along the guide rail 22 to linearly move the drive unit suspension 14, and the drive tire 1 is also pushed downward. As a result, a predetermined wheel pressure is secured, and the drive tire 1 can travel without slipping. Further, since the wheel pressure adjusting spring 12 expands according to the amount of wear of the drive tire 1 to reduce the wheel pressure, the spring adjuster 13 adjusts the mounting height of the spring 12 to secure the necessary wheel pressure. It is configured.

In the above embodiment, the guide roller 21 and the guide rail 22 are used instead of the upper link in the conventional suspension link mechanism to guide the vertical movement of the drive unit suspension 14, so that the structure of the suspension link mechanism is simple. It has become. Therefore, it can be manufactured at low cost and the assembling becomes easy, and the greasing points are reduced by the amount that the upper link is not used, and the serviceability is improved.

[0015]

As described above, the suspension link mechanism of the reach type forklift according to the present invention is
Since the drive unit suspension is rotatably connected to a swing link provided swingably on the frame of the vehicle body and the guide roller and the guide rail are used to guide the vertical movement of the drive unit suspension, the upper link in the conventional link mechanism is No link required. For this reason,
The structure of the link mechanism is simplified, the assembly is facilitated, and the manufacturing cost can be reduced. Further, since the upper link is not used, the number of pivot points is reduced and the number of greasing points is reduced, so that the serviceability is improved.

[Brief description of drawings]

FIG. 1 is a side view showing a suspension link mechanism of a reach type forklift according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the suspension link mechanism of FIG.

3 is a cross-sectional view showing a guide rail and a guide roller used in the suspension link mechanism of FIG.

FIG. 4 is a side view showing a suspension link mechanism of a conventional reach type forklift.

5 is an exploded perspective view of the suspension link mechanism of FIG.

[Explanation of symbols]

 1 Drive Tire 5 Drive Unit 12 Wheel Pressure Adjusting Spring 13 Spring Adjuster 14 Drive Unit Suspension 15, 18 Shaft 16 Swing Link 17 Body Frame 19 Caster Tire 21 Guide Roller 22 Guide Rail 23 Reinforcing Plate.

Claims (1)

[Claims] 1. A suspension link mechanism for a reach-type forklift having a drive wheel and a driven wheel at a rear portion of a vehicle body, the swinging link being swingably provided on a frame of the vehicle body and supporting the driven wheel. A drive unit suspension that is rotatably connected to the drive link and supports a drive unit that drives the drive wheels; a guide roller provided on the drive unit suspension; A suspension link mechanism for a reach-type forklift, comprising: a guide rail that operates and a wheel pressure adjusting spring that biases the drive unit suspension downward with respect to a frame of a vehicle body.