JPH0633489A - Safety device of operation car of back-hoe, etc. - Google Patents

Abstract

PURPOSE:To make constant the circumferential speed in the case a bucket is rotated in a separate position in a back-hoe, etc., and to eliminate malfunction in the case an operator leaves the seat. CONSTITUTION:In a bucket 1 of a back-hoe or in a gondola 2 of a high place operation car, in order to make constant a turning circumferential speed of the bucket 1 or gondola 2 in the case a turning table of the machine concerned is turned, the machine has a distance between the turning center of the bucket 1 or gondola 2, a turning motor flow control function and an operating function. A lock lever 3, a cut-off solenoid valve 4 and a one-touch deceleration solenoid valve 5 are provided, and when an operator leaves his or her seat, if the lock lever is operated by him or her, a hydraulic circuit of an oil pressure remote control valve is cut off by the cut-off solenoid valve 4, and engine speed is switched to idling speed by the one-touch deceleration solenoid valve 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety control mechanism for a work vehicle such as a backhoe or a boom type work platform for aerial work.

[0002]

2. Description of the Related Art In a backhoe or boom type aerial work vehicle, the positions of buckets and gondola move away from and approach the center of the swivel base. On the other hand, the flow rate of the hydraulic pressure that drives the swivel base motor is the same regardless of the positions of the bucket and the gondola. Therefore, if the bucket or gondola is largely projected, the tip moves at a large peripheral speed when turning, which causes a problem of collision with an obstacle against the intention of the operator.

Further, as a safety device such as a backhoe, there has been a technique of performing a microcomputer control and operating a one-touch deceleration mechanism so as to make an engine rotation an idling rotation when a load is not applied. It is also known that a sensor detects that the operator has left the seat and operates the one-touch decel solenoid valve by this operation.

[0004]

SUMMARY OF THE INVENTION The present invention controls the flow rate of a swivel motor so that the bucket or gondola does not rotate at a high peripheral speed when the bucket or gondola largely projects from the swivel. If the operator operates the lock lever and cancels the work on the backhoe,
The cut-off solenoid valve shuts off the hydraulic remote control valve,
The operation of the working unit is stopped, and the one-touch decel solenoid valve is used to slow down the engine to idling.

[0005]

The problems to be solved by the present invention are as described above, and the means for solving the problems will be described below. That is, in the bucket 1 on the backhoe or the gondola 2 of the aerial work vehicle, the turning center and the bucket 1 or the turning center speed of the bucket 1 and the gondola 2 are kept constant when the turning base of the machine is turned. Gondola 2
The distance, the swing motor flow rate adjustment function, and the calculation function are provided.

Further, in the backhoe, the lock lever 3, the cutoff solenoid valve 4, and the one-touch decel solenoid valve 5
When the operator leaves the seat 6 and operates the lock lever 3, the cut-off solenoid valve 4 is provided.
The hydraulic circuit of the hydraulic remote control valve is cut off by means of the one-touch decel solenoid valve 5, and the engine rotation is made idling rotation.

[0007]

[Operation] Next, the operation will be described. Bucket 1 and gondola 2
Since the flow rate of the swivel base motor 10 is controlled by calculating the distance from the swivel base 7 and the swivel base 7, the peripheral speeds of the bucket 1 and the gondola 2 are always the same even if they are distant from each other. It is possible to reduce the occurrence accidents with things. Further, by operating the lock lever 3, the work machine operation lever 2
Even if 3 is mistakenly operated, the working machine does not move. The engine speed also drops to idling speed.

Next, examples will be described. 1 is a side view of a boom-type aerial work vehicle, FIG. 2 is a side view of a backhoe, and FIG.
Is a control block diagram of the turning peripheral speed control mechanism of the present invention, FIG. 4 is a side view showing a control mechanism of the cutoff solenoid valve 4 and the one-touch decel solenoid valve 5 by the lock lever 3, and FIG. 5 is a safety mechanism by the lock lever 3. It is a control block diagram of.

This will be described with reference to FIGS. 1 and 2. In FIG. 1, a telescopic raising / lowering boom 9 is supported on a crawler type traveling device 8 via a swivel base 7, and the telescopic raising / lowering boom 9 can adjust the vertical and far positions. The gondola 2 is disposed at the tip of the telescopic lifting boom 9, and an operator rides on the gondola 2 to perform work in high places.
However, the swivel motor 10 of the swivel 7, which rotates the telescopic lifting boom 9 and the gondola 2, has been a constant flow motor in the past. Therefore, the rotation speed of the swivel base 7 is the same when the gondola 2 is directly above the swivel base 7 and when the gondola 2 is at the farthest position. Therefore, if the operator rotates the swivel base 7 in a normal manner without considering that point,
At the position of the gondola 2, the speed was considerably high, and there was a problem that it collided with an obstacle in an instant.

Further, FIG. 2 shows a normal backhoe. Also in the case of the backhoe, the position of the bucket 1 arranged on the crawler type traveling device 8 and the swivel base 7 is
It moves away from or near the swivel base 7. When the swivel base 7 is rotated at the same speed as the normal speed with the bucket 1 projected far away, there is a risk that the bucket 1 and the obstacle approach and collide with each other in an instant. The present invention solves such a problem.

In order to suppress the above-described state in which the peripheral speed of the bucket 1 or the gondola 2 becomes abnormally high, the flow rate of the swivel base motor 10 of the swivel base 7 may be reduced and slowed down. However, if the bucket 1 and the gondola 2 approach each other and rotate at a low speed, the work efficiency does not increase.

As shown in FIG. 3, the present invention is constructed so that the bucket 1 and the gondola 2 always rotate at the same peripheral speed even when the positions of the bucket 1 and the gondola 2 change in perspective. That is, the boom angle sensor 11 and the arm angle sensor 20 are used as sensors.
A bucket angle sensor 12, a boom extension / contraction distance sensor 13, an engine speed sensor 14, a hydraulic oil temperature detection sensor 19 and the like are provided. And boom angle sensor 1
1, arm angle sensor 20, and bucket angle sensor 12
Then, the signal detected by the boom extension / contraction distance sensor 13 is calculated, and the distance from the turning center of the bucket 1 and the gondola 2 is calculated by the calculation device 26.

The signal from the engine speed sensor 14 is
The signal is compared with the peripheral speed set in the reference peripheral speed setter 16, and this signal is input to the swing motor flow rate calculation circuit 15. Also, the oil temperature detected by the hydraulic oil temperature sensor 19 is corrected by the correction circuit 18
Is corrected and transmitted to the swing motor flow rate calculation circuit 15. Based on these signals, the flow rate of the swivel base motor 10 is determined by the swing motor flow rate calculation circuit 15, and is input to the flow rate adjusting solenoid proportional valve 17 to adjust. As a result, the rotation speed of the swivel base motor 10 is controlled so that the peripheral speed during turning can be kept constant regardless of the positions of the bucket 1 and the gondola 2.

Next, description will be made with reference to FIG. A lock lever 3 is provided on the side of the seat 6. The lock lever 3
Is located in the aisle where the operator descends,
The operator cannot leave the seat unless it is rotated in the locking direction. A lock switch 21 is provided at the base of the lock lever 3.
When the lock switch 21 is turned on, the cut-off solenoid valve 4 interposed as shown in the circuit of FIG. 5 shuts off the hydraulic circuit. By disconnecting the circuit of the cut-off solenoid valve 4, the hydraulic remote control valve 22 is moved to the work machine operating lever 23
Even if it is operated by, the pressure oil will not flow to the working machine cylinder. This allows bucket 1 and gondola 2
It is possible to lock the working machine parts such as.

At the same time, when the lock switch 21 is turned on, the one-touch decel solenoid valve 5 operates. By operating the one-touch decel solenoid valve 5, the accelerator lever of the engine is rotated to the low speed side. with this,
The engine speed is idling, and the engine speed does not rise any further.

Further, the speed increasing travel pedal 2 is provided at the base of the operation column.
4 is provided, and when the speed-increasing travel pedal 24 is operated, the speed-increasing operation switch 25 is operated, so that the speed is set to 2
It is configured to be fast. However, the second traveling speed is a speed for traveling only and is not used during the work. If the working machine is operated while traveling at the second speed, a dangerous state will occur. This acceleration pedal 24
Even when the second speed is reached by the speed increasing operation switch 25, the cutoff solenoid valve 4 is operated to operate.

[0017]

Since the present invention is constructed as described above, it has the following effects. That is, since it is configured as in claim 1, the problem that the bucket 1 and the gondola 2 rotate at a position largely separated from the swivel base 7 rotates at a high peripheral speed and collides with an obstacle is solved. I was able to do it.

According to the present invention, the cut-off solenoid valve 4 and the one-touch decel solenoid valve 5 are always operated when the operator leaves the seat 6, so that the working machine does not malfunction. Moreover, the engine does not become a high speed and consumes unnecessary fuel, and the dangerous state of a high speed is no longer generated.

[Brief description of drawings]

FIG. 1 is a side view of a boom-type aerial work vehicle.

FIG. 2 is a side view of a backhoe.

FIG. 3 is a control block diagram of a turning peripheral speed control mechanism of the present invention.

FIG. 4 is a side view showing a control mechanism of the cutoff solenoid valve 4 and the one-touch decel solenoid valve 5 by the lock lever 3.

FIG. 5 is a control block diagram of a safety mechanism using a lock lever 3.

[Explanation of symbols]

 1 bucket 2 gondola 3 lock lever 4 cutoff solenoid valve 5 one-touch decel solenoid valve 6 seat 7 swivel 8 crawler type traveling device

Claims (2)

[Claims] 1. In a bucket 1 of a backhoe or a gondola 2 of an aerial work vehicle, the turning center of the bucket 1 and the gondola 2 is set so as to be constant when the swivel base of the machine is turned. A safety device for a working vehicle such as a backhoe, which is provided with a distance from the bucket 1 or the gondola 2, a turning motor flow rate adjusting function, and a calculation function. 2. The backhoe is provided with a lock lever 3, a cutoff solenoid valve 4, and a one-touch decel solenoid valve 5, and when the operator leaves the seat 6,
When the lock lever 3 is operated, the cutoff solenoid valve 4 shuts off the hydraulic circuit of the hydraulic remote control valve, and the one-touch deceleration solenoid valve 5 causes the engine rotation to be idling rotation.