JPH071986A - Safety device for work vehicle - Google Patents

Abstract

PURPOSE:To improve the working efficiency in maintenance work without deteriorating safety of work. CONSTITUTION:An operation seat 25 is supported by a frame 27 according to the existence of a seated operator so as to be movable vertically freely within a preset range as well as in a condition of being moved and energized upward, and is constituted so that an engine is stopped according to detecting operation of a detecting switch SW to detect that the seat is put in an unseated condition when an operation member 28 arranged in the operation seat 25 acts in a condition where the operation seat 25 is moved upward. A checking member 29 is arranged so as to be movable freely in the direction for crossing the moving direction of the operation seat 25 over an ascent checking position to check to act on the detecting switch SW by engaging with the operation member 28 while moving into a vertical movement locus of the operation member 28 and an unoperated position separate from the vertical movement locus of the operation member 28, and a spring 30 is arranged to retreat the checking member 29 toward the unoperated position when the operation seat 25 is moved downward in a condition where the checking member 29 is put in the ascent checking position and is engaged with the operation member 28.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention supports a driver's seat on a frame in such a manner that it can move up and down within a set range based on whether or not a driver is seated and is urged to move upward. A work vehicle configured to detect a non-seated state by operating an operating member provided on a driver's seat when the vehicle is moved upward, and to stop the engine based on the detection operation of the detecting means. Safety device.

[0002]

2. Description of the Related Art In the above-mentioned work vehicle safety device, conventionally, when the detecting means detects and operates, the engine is always stopped, and when the driver leaves the driver's seat while the engine is being driven, It was configured to ensure safety by stopping the engine in an emergency.

[0003]

With the above-mentioned conventional structure, the engine is stopped in an emergency when the driver is not seated in the driver's seat, so that safety in work can be ensured. When it is necessary to perform maintenance work while driving the work device etc. with the engine stopped, the engine is driven while seated in the driver's seat and another worker performs maintenance work. Therefore, there is an adverse effect such as a decrease in work efficiency, and there is room for improvement in this respect. The present invention aims to eliminate the above-mentioned problems.

[0004]

According to a feature of the present invention, in the safety device for a work vehicle described at the beginning, the detecting means is moved to a vertical movement locus of the operating member and engaged with the operating member. A check member that is movable in a direction that intersects with the moving direction of the driver's seat over a lifted check position that prevents the operation member from moving up and down and a non-acting position that separates from the vertical movement trajectory of the operating member. In the state where the member is in the ascending / descending restraint position and is engaged with the operating member, when the driver's seat moves downward, a moving means for retracting the restraint member toward the non-acting position is provided.

[0005]

When the restraint member is set to the raising and restraining position while seated on the driver's seat, the operating member engages with the restraint member even if the operator separates from the driver's seat, and further raising operation is not possible. The engine is never stopped because it is restrained. In this state, a worker away from the driver's seat can perform maintenance work while the engine is driven. Then, after the maintenance work is completed, when the worker sits down on the driver's seat again, if the driver's seat is lowered due to the weight of the worker, the restraint member is automatically retracted to the non-acting position by the moving means. The engine emergency stop state is surely set at the next disembarkation without switching the check member to the non-acting position.

[0006]

Therefore, in the case of performing normal work, the engine emergency stop is activated when the worker leaves the driver's seat to ensure the safety of the work. Based on the operator's intention to switch the member to the lifting and restraining position,
It is possible to set the engine emergency stop to a state where it does not operate, and it is possible for one person to handle it. Moreover, switching to the non-acting position of the check member is automatically performed by sitting on the driver's seat. It was possible to prevent problems such as the engine emergency stop not working against the operator's intention due to forgetting the switching operation, etc., and to improve work efficiency without lowering safety.

[0007]

Embodiments will be described below with reference to the drawings. Figure 1
Shows a riding lawn mower. This lawnmower is constructed by connecting a lawnmower 1 to a front portion of a riding type traveling body so as to be able to move up and down. The traveling machine body is provided with a boarding operation unit 2 at the front of the machine body and a driving unit 3 at the rear, and is provided with unsteered left and right front wheels 4 and 4 and steerable left and right rear wheels 5 and 5, respectively. It is driven to form a four-wheel drive type. A hydraulic oil tank 8 is provided on the lower rear side of the left front wheel fender 7, and the hydraulic tank 8 is arranged so as to be located closer to the inside of the vehicle than the outer end of the front wheel 4.

As shown in FIG. 2, the lawnmower 1 is provided with one reel mower 9a at the center of the front side, and two reel mowers 9b and 9c are provided behind the reel mower 9a in parallel with each other. Hydraulic motors 10a, 10b, 10c
It is configured to be driven to rotate by
It is configured to move up and down by 1. That is, a pair of left and right elevating links 13, 13 pivotally supported on the front part of the machine body frame 12 of the traveling machine body so as to be vertically swingable around the horizontal axis is lifted and lifted by the lift arm 14 which is rotationally driven by the hydraulic cylinder 11. It is configured as follows. The rear cover 15 of each reel mower is, as shown in FIGS. 6 and 7,
It is pivotally supported with respect to the mower deck 16 so as to be vertically swingable about a horizontal axis and to be positionally adjustable in an arbitrary posture. That is,
One end of a fixed support shaft 15a integrally fixed to the rear cover 15 is inserted into and supported by a mounting stay 17 provided on the mower deck 16, and a screw portion 18 is formed on the other end side, and one end is mounted with a nut 20 via a spring washer 19. The stay 17 is configured to be fastened and fixed.

The balance weight 21 is provided at the rear of the traveling machine body in order to prevent the rear side of the machine body from being lifted by the weight of the lawnmower 1 and making it difficult to perform steering operation of the rear wheels 5.
The balance weight 21 is mounted on the front side of the machine body so that there is little damage to the lawn by the rear wheels 5 during the lawn mowing work, and on the rear side of the machine body so that the steering operation can be surely performed when traveling on the road. It is configured so that it can be slid back and forth to be positioned. That is, as shown in FIG. 2, the balance weight 21 is attached to the left and right slide rods 22, 2.
It is configured to be slidably supported by the machine body frame 12 by means of 2, and to be pushed and pulled by a hydraulic cylinder 23 at the central portion for sliding movement. The switching operation of the hydraulic cylinder 23 is configured to be performed based on the switching operation of the operating lever 24 of an auxiliary transmission mechanism (not shown) provided in the machine body drive system.

In this lawnmower, a safety device is provided to stop the engine 26 in an emergency when the operator leaves the driver's seat 25. More specifically, as shown in FIGS.
The operator seat 25 is vertically slidable within a certain range on a support member 27 (an example of a frame) provided upright from the machine body frame 12, and a spring installed in the support member 27 supports the driver seat 25 in an upwardly movably supported state. When the driver is seated, the driver's seat 25 located at an upper position depending on the weight of the operator
Is configured to descend downward. Then, when the driver's seat 25 rises to near the upper end, the operating member 28 that slides up and down integrally with the driver's seat 25 abuts on the limit switch SW [an example of detecting means] attached to the support member 27. The limit switch SW is switched to operate the engine stop circuit. Therefore, even if the driver leaves the driver's seat 25 while the engine 26 is being driven by mistake, the engine 2
It is designed so that 6 can be stopped in an emergency to ensure work safety.

When the reel mower is rotated in the reverse direction to grind the cutting blade, the engine 26 can be set in a state where the engine 26 does not stop emergency even if the operator leaves the driver's seat 25. That is, the raising and restraining position for preventing the operation member 28 from moving in the vertical movement locus and engaging with the operation member 28 and acting on the limit switch SW, and the non-action of moving away from the vertical movement locus of the operation member 28. A check member 29 is provided which is movable in the direction crossing the moving direction of the driver's seat 25, that is, in the machine longitudinal direction, and the check member 29 is in the ascending and descending position and engages with the operating member 28. In this state, when the driver's seat 25 moves downward, the coil spring 30 is provided as a moving means for retracting the restraint member 29 toward the non-acting position. More specifically, the restraint member 29 is formed by bending a rod material into a dogleg shape, is supported slidably in the left and right directions by a bracket 31 fixed to the support member 27, and is biased to the outside of the machine by a coil spring 30. And the check member 29 of the operating member 28.
A rubber material G having a large friction coefficient is attached to the contact action surface with respect to the driver seat 25 while the check member 29 is operated against the urging force of the coil spring 30 toward the front side of the machine body, that is, in the lift check position. When rising, the spring force of the coil spring 30 is set so that the restraining member 29 is held at the rising restraining position by the lifting / lifting biasing force of the driver's seat 25 and the frictional force of the rubber material G. Therefore, in the restrained state, when the operator sits down on the driver's seat 25 and goes down, the frictional force is released, and the spring force of the coil spring 30 automatically retracts the inactive position.

[Other Embodiments] The engagement state between the operating member 28 and the restraint member 29 is not the frictional force as described above, but is engaged by engaging in the vertical direction to maintain the restraint state and operate. The engagement may be released by the downward movement of the member.

It should be noted that reference numerals are added to the claims for facilitating the comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

[Figure 1] Overall side view of the lawn mower

[Figure 2] Overall plan view of the lawn mower

FIG. 3 is a cutaway side view showing a driver seat support structure.

FIG. 4 is a front view showing a driver seat support structure.

FIG. 5 is a front view of a restraint member arrangement portion.

FIG. 6 is a side view of the reel mower.

FIG. 7 is a bottom view of the reel mower.

[Explanation of symbols]

 25 driver's seat 26 engine 27 frame 28 operating member 29 restraining member 30 biasing means SW detecting means

Claims (1)

[Claims] 1. A driver's seat (25) is supported on a frame (27) in a state in which it can be moved up and down within a set range based on whether or not a driver is seated and is biased to move upward. A detection means (SW) is provided for detecting that the operating member (28) provided on the driver seat (25) is in the non-seated state while the (25) is moved upward, and the detection means (S) is provided.
A safety device for a work vehicle configured to stop an engine (26) based on a detection operation of (W), the operation member (28) being moved within a vertical movement locus of the operation member (28). And the operating member (2), which is engaged with and is prevented from acting on the detection means (SW).
8) A check member (29) movable in a direction intersecting the moving direction of the driver's seat (25) is provided over a non-acting position away from the vertical movement locus of 8), and the check member (29) is raised. When the driver's seat (25) is moved downward in the restraint position and engaged with the operating member (28), the restraint member (29) is moved.
Moving means (30) for retracting the vehicle toward the non-acting position
Safety equipment for work vehicles equipped with.