JP2004035155A - Forklift driver's seat tilting device and forklift provided with it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable vertical eye movement according to elevation of a load without requiring an operator to tilt his head, to improve work efficiency and to reduce fatigue of the operator in a forklift. <P>SOLUTION: This forklift is provided with a manipulation part for manipulating a fork 3 and a driver's seat 6 which can tilt in the elevation direction to the front of a car body 2. The driver's seat 6 is tilted and driven in linkage with elevation of the fork 3 by an oil pump for supplying oil to a lift cylinder 5 for elevation of the fork 3, a flow separating valve for separating part of the oil supplied to the lift cylinder 5, and a cylinder 7 for tilting the driver's seal which contracts / extends by oil separated by the flow separating valve for tilting the driver's seat 6. With this, the operator can easily move his eyes vertically according to the elevation of the load. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a driver's seat tilting device for a forklift and a forklift provided with the same.
[0002]
[Prior art]
2. Description of the Related Art In a forklift that lifts and lowers luggage such as containers, in order to improve the safety of an operator (driver) and the working environment, an operation unit including a lever and a pedal for the operator to operate a fork, and an operator Is provided with a driver's seat (cabin) formed so as to surround the seat. FIG. 4 shows how a forklift equipped with such a driver's seat loads a load at a high place. The forklift 100 includes a vehicle body 2, a fork 3 for supporting a load L, a mast 4 for supporting the fork 3 slidably in a substantially vertical direction, and a lift cylinder 5 for driving the fork 3 up and down. A driver's seat 6 is provided. Normally, the driver's seat 6 is fixed to the vehicle body 2, but in some cases the driver's seat 6 can be inclined in the angle of attack with respect to the vehicle body 2 only during maintenance in order to facilitate maintenance of the lower part of the driver's seat 6. In addition, the fork 3 is raised to a position higher than the eye level of the operator sitting in the driver's seat 6 during the loading operation of the load L to a high place.
[0003]
[Problems to be solved by the invention]
By the way, in the work of stacking the load L by the forklift 100, the visibility of the operator is considered to be an important point. As shown in FIG. 4, when the forklift 100 is operated to stack the load L higher than the eye level of the operator, the operator works while looking up near the lower end of the load L. In the conventional forklift 100, since the driver's seat 6 is fixed to the vehicle body 2, the operator tilts his / her head backward to see the luggage L so that the line of sight E moves in the horizontal direction H. Must be directed upward by an angle θ. For this reason, when loading the luggage L to a high place, the operator is forced to have an unnatural posture, and the operator's neck becomes tired, and the work efficiency is reduced.
[0004]
The present invention has been made in order to solve the above-described problems, the driver's seat is tilted in accordance with the lifting and lowering of luggage, so that the operator can move his or her line of sight up and down without tilting the head itself, It is an object of the present invention to provide a forklift that reduces operator fatigue and improves work efficiency.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a first aspect of the present invention relates to a forklift driver's seat tilting apparatus in which a fork is provided on a mast erected at a front portion of a vehicle body so as to be able to move up and down. A driver's seat that can be tilted in the angle of attack with respect to the front of the vehicle body, and a drive unit that tilts the driver's seat in conjunction with the elevation of the fork.
[0006]
In this configuration, the driver's seat is driven by the driving means in conjunction with the lifting and lowering of the fork, and is inclined in the angle of attack with respect to the front of the vehicle body. That is, the driver's seat is tilted backward in conjunction with the rise of the fork, and tilted forward in conjunction with the fall of the fork. Thus, the luggage supported by the fork is always positioned in the direction of the operator's front line of sight, even if the operator does not tilt the head.
[0007]
According to a second aspect of the present invention, in the tilting device for a forklift driver according to the first aspect, the driving means includes a lift cylinder for lifting and lowering the fork, an oil pump for supplying oil to the lift cylinder, and an oil pump. It is provided with a diverting valve for diverting a part of the oil supplied from the pump to the lift cylinder, and a driver seat tilting cylinder that expands and contracts by the oil diverted by the diverting valve and tilts the driver's seat.
[0008]
In this configuration, the driver's seat is tilted by using the oil pump as a drive source by connecting the driver's seat tilting cylinder to the hydraulic path from the oil pump for driving the lift cylinder to the lift cylinder via a branch valve. You.
[0009]
According to a third aspect of the present invention, there is provided a forklift including the driver's seat tilting device according to the first or second aspect. According to this configuration, in a forklift provided with the driver's seat tilting device, an operation equivalent to that of claim 1 or claim 2 can be obtained.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a forklift provided with a driver's seat tilting device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1A shows a state where the fork of the forklift is lowered to a lower limit position, and FIG. 1B shows a state where the fork of the forklift is raised. FIG. 2 shows a hydraulic device for tilting the driver's seat of a forklift. The forklift 1 includes a vehicle body 2, a fork 3 for lifting and lowering a load L, a mast 4 for supporting the fork 3 so as to be able to move up and down, a lift cylinder 5 for driving the fork 3 to move up and down, and operating the fork 3. And a driver seat tilting cylinder (drive means) 7 for tilting the driver seat 6. The mast 4 includes an outer mast 41 mounted on a front portion of the vehicle body 2 and an inner mast 42 slidably engaged with the outer mast 41, and is tilted and driven by the mast tilting cylinder 10. One end 51 of the lift cylinder 5 is connected near the lower end of the outer mast 41, and the other end 52 is connected near the upper end of the inner mast 42. In the vicinity of the upper end of the inner mast 42, a chain wheel 9 on which a fork elevating chain 8 is hung is provided. One end 81 of the chain 8 is connected near the upper end of the outer mast 41, and the other end 82 is connected to the fork 3.
[0011]
The driver's seat 6 is located behind the mast 4 and is arranged toward the front of the vehicle body. The rear portion of the driver's seat 6 is pivotally supported by a support shaft 61 provided on the vehicle body 2. It is possible. One end 71 of the driver's seat tilting cylinder 7 is connected to the vicinity of the front lower end of the driver's seat 6, and the other end 72 is connected to the vehicle body 2. The driver's seat 6 is tilted by the expansion and contraction of the driver's seat tilting cylinder 7.
[0012]
Next, a hydraulic device (drive means) for lifting and lowering the fork 3 and driving the driver's seat in the forklift 1 will be described with reference to FIG. The hydraulic device has an oil pan 11, a strainer 12, an oil pump 13, a main valve 14, and a diverter valve 15. The oil pump 13 sucks up oil stored in the oil pan 11 via the strainer 12 and supplies the oil to the lift cylinder 5. The main valve 14 adjusts the flow rate of oil supplied to the lift cylinder 5 from the oil pump 13 in response to an operation by an operator. The flow dividing valve 15 diverts a part of the oil supplied from the main valve 14 to the lift cylinder 5 and supplies the oil to the driver seat tilt cylinder 7. The ratio of the oil flow diverted by the diverting valve 15 depends on the specifications of the forklift, but in the present embodiment, the diverting valve 15 is 10 (lift cylinder 5): 1 (driver seat tilt cylinder 7). The oil is split at the ratio of
[0013]
In the above-described hydraulic device, the oil pumped by driving the oil pump 13 is supplied to the lift cylinder 5 via the main valve 14 and the flow dividing valve 15, and the lift cylinder 5 is extended. Due to the extension of the lift cylinder 5, the inner mast 42 moves upward as shown in FIG. At this time, the chain wheel 9 acts as a moving pulley while moving up together with the inner mast 42, and pulls up the fork 3 via the chain 8. At the same time, the oil diverted by the flow dividing valve 15 is supplied to the driver's seat tilting cylinder 7, and the driver's seat tilting cylinder 7 is extended. The extension of the driver's seat tilting cylinder 7 causes the driver's seat 6 to tilt rearward in conjunction with the rise of the fork 3. On the other hand, when the operator performs the operation of lowering the fork 3, the hydraulic pressure of the cylinder 5 and the driver's seat tilting cylinder 7 is reduced, and the lift cylinder 5 and the driver's seat tilting cylinder 7 are contracted. Thereby, the inner mast 42 and the fork 3 are lowered, and the inclination of the driver's seat 6 is restored. In addition, between the vehicle body 2 and the driver's seat 6, a steering hose, a cargo handling hose, an accelerator wire, a piping such as a harness, a wiring, and the like are arranged, all of which are made of a flexible member. Since it is formed, it does not hinder the tilting operation of the driver's seat 6.
[0014]
FIG. 3 shows a state where the luggage L is loaded at a high place by the forklift 1 configured as described above. At this time, the driver's seat 6 is tilted backward in conjunction with the ascent of the fork 3, and accordingly, the luggage supported by the fork is always positioned in the direction of the operator's front line of sight. The line of sight E can be moved upward without tilting. As a result, fatigue of the operator can be reduced, and work efficiency can be increased. Further, since the driver's seat 6 is inclined in the angle of attack in conjunction with the lifting and lowering of the fork 3, the operator's field of view is opened upward, the attention on the upward direction is increased, and safety is improved.
[0015]
Further, a part of the oil supplied to the lift cylinder 5 is diverted by the diverting valve 15 and supplied to the driver seat tilt cylinder 7. Therefore, the oil pump 13 for driving the lift cylinder 5 can be applied as a drive source of the driver's seat tilting cylinder 7, and the structure of the driver's seat tilting device can be simplified.
[0016]
The present invention can be variously modified without being limited to the configuration of the above embodiment. For example, the present invention is not limited to the mode in which the driver's seat 6 is tilted in accordance with the rise of the fork 3, but may be a mode in which only the seat on which the operator sits is tilted, or a mode in which the seat and the operation unit are tilted. Further, the flow dividing valve 15 may be controlled so that the inclination of the driver's seat 6 is started after the fork 3 has risen to a height substantially matching the height of the eyes of the operator. Further, the inclination of the driver's seat 6 may be configured to be driven by a hydraulic system of a different system from that for raising and lowering the fork 3.
[0017]
【The invention's effect】
As described above, according to the first aspect of the present invention, the driver's seat is driven by the driving means and tilts in the attack angle direction in conjunction with the fork elevating, so that the operator himself / herself raises his / her head in accordance with the elevating of the load. Without tilting, the line of sight can be moved upward and the luggage can be visually recognized. As a result, fatigue of the operator can be reduced, and work efficiency can be increased.
[0018]
According to the second aspect of the present invention, a part of the oil supplied from the oil pump to the lift cylinder is diverted by the diverting valve and supplied to the driver's seat tilt cylinder. Therefore, the oil pump 13 for driving the lift cylinder 5 can be applied as a drive source of the driver's seat tilting cylinder 7, and the structure of the driver's seat tilting device can be simplified.
[0019]
According to the invention of claim 3, in a forklift provided with the driver's seat tilting device, the same effect as that of claim 1 or claim 2 can be obtained.
[Brief description of the drawings]
FIG. 1A is a side view of a forklift according to an embodiment of the present invention in a state where the fork is lowered, and FIG. 1B is a side view of the forklift in a state where the fork is raised.
FIG. 2 is a system diagram showing a hydraulic device of the forklift.
FIG. 3 is a diagram showing a state in which luggage is stacked at a high place by the forklift.
FIG. 4 is a diagram showing a state where luggage is stacked at a high place by a conventional forklift.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Forklift 2 Body 3 Fork 4 Mast 5 Lift cylinder 6 Driver's seat 7 Driver's seat inclination cylinder (drive means)
13 Oil pump (drive means)
15 Dividing valve (driving means)

Claims (3)

In a forklift driver's seat tilting device in which a fork is provided to be able to move up and down on a mast erected in the front of the vehicle body,
A driver seat having at least an operation unit for operating the fork, and being tiltable in the angle of attack with respect to the front of the vehicle body;
A driver for tilting the driver's seat in conjunction with the lifting and lowering of the fork. The drive means includes a lift cylinder for raising and lowering the fork, an oil pump for supplying oil to the lift cylinder, a flow dividing valve for diverting a part of the oil supplied from the oil pump to the lift cylinder, The driver's seat tilting device for a forklift according to claim 1, further comprising: a driver's seat tilting cylinder that expands and contracts by oil diverted by a flow splitting valve and tilts the driver's seat. A forklift equipped with the driver's seat tilting device according to claim 1 or 2.

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