JPH05170399A - Overturn preventive device for industrial vehicle - Google Patents

Abstract

PURPOSE:To provide an overturn preventive device for an industrial vehicle by which at the time of normal travel, traveling can be carried out without restraining the maximum speed at this time and at the time of stop, stopping can be carried out safely by means of a controller and overturn can be prevented. CONSTITUTION:The device has a load detecting means 9 to detect lifting load, a lifting detecting means 10, a forward tilting angle detecting means 11 to detect the forward tilting angle of a lifting device, a front obstacle detecting means 12 to detect the existence of a front obstacle, a vehicle speed detecting means 15 and a brake stepping on amount detecting means 14, and in addition, it has a controller 17 that calculates a distance by which a vehicle can stop safely, from detection values from these detecting means, and at the same time controls the braking force of a brake 16.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fall prevention device for industrial vehicles such as forklifts.

[0002]

2. Description of the Related Art A fall problem is one of safety problems in industrial vehicles, especially in forklifts. Among the fall problems, there is a problem of falling forward when traveling or working with a high load. As a means for solving this problem, there is a means for controlling the traveling speed by detecting the moment around the front of the load, the fork lift and the tilt angle.

[0003]

In the above-mentioned conventional technique, since the method of uniformly suppressing the traveling speed is adopted as the actual fall prevention means, the result is that the maximum speed is suppressed even in the normal traveling state. It caused the deterioration of work cycle time.

The present invention has been made in view of the above, and during normal traveling, the vehicle can travel without suppressing the maximum speed at this time, and at the time of stopping, it can be stopped safely by the controller to prevent a fall. An object is to provide a fall prevention device for an industrial vehicle.

[0005]

In order to achieve the above object, an industrial vehicle overturn prevention device according to the present invention comprises a load detection means for detecting a lift load, a lift detection means, and a forward tilt angle of the lift device. The vehicle has a forward lean angle detecting means for detecting, a forward obstacle detecting means for detecting the presence or absence of an obstacle in front, a vehicle speed detecting means, and a brake depression amount detecting means, and further, the vehicle is safe from the detection values from these detecting means. The controller has a controller that calculates the distance that can be stopped and controls the braking force of the braking device.

[0006]

[Operation] The controller calculates the safe stop distance of the vehicle from the observation information from each detection means. And if there is no obstacle within the safe stop distance and the brake pedal is stepped on slowly, the stop operation is performed regardless of the controller.
If there is no obstacle within the safe stop distance and the brake pedal is pressed hard, the brake hydraulic pressure control program works to stop safely without falling. Furthermore, if a front obstacle is detected, the controller performs a safe stop.

[0007]

EXAMPLES Examples of the present invention will be described with reference to the drawings. In the figure, reference numeral 1 denotes a forklift truck which is an example of an industrial vehicle, and 2 denotes a vehicle body running with front wheels 3 and rear wheels 4 and 5.
Is a mast device attached to the front end of the vehicle body 2 so as to be tiltable in the front-rear direction, 6 is a tilt cylinder for tilting the mast 5 back and forth, 7 is a fork that moves up and down along the mast device 5, and 8 is a mast device. An elevating cylinder that moves the fork 5 up and down to elevate and lower the fork 7, which are the same as a normal forklift.

The lifting cylinder 8 is provided with a load sensor 9 for detecting the hydraulic pressure acting on the lifting cylinder 8 to detect the load loaded on the fork 7. Further, the mast device 5 has a fork height detection sensor 10 for detecting the height of the fork 7, and the tilt cylinder 6 has a forward tilt angle detection for detecting the forward tilt angle (tilt angle) of the mast device 5 from the extension / contraction length thereof. A sensor 11 is attached. Further, the mast device 5 detects an obstacle in front of the vehicle,
For example, a front obstacle detection sensor 12 such as an ultrasonic distance sensor
Is installed. A brake pedal 13 is provided on the front floor of the vehicle body 1 in addition to the accelerator pedal. A brake depression amount detection sensor 14 is attached to the brake pedal 13, and a vehicle speed detection sensor 15 is attached to the front wheel shaft.
Is provided. A brake device 16 is provided on the front wheel shaft. The vehicle body 1 is provided with a controller 17 that collects the detection information from the above-described sensors, calculates the distance at which the vehicle can safely stop from these, and controls the braking force of the brake device 16.

In the above structure, the controller 17 calculates the safe stop distance from the information observed by the load sensor 9, the fork height detection sensor 10, the forward lean angle detection sensor 11 and the vehicle speed detection sensor 15. On the other hand, the front obstacle detection sensor 12 monitors whether or not the obstacle is within the safe stop distance.

Correspondence in the stop operation by depressing the brake pedal 13 is as follows (1) to (3). (1) When there is no obstacle within the safe stop distance and the brake pedal 13 is stepped on slowly, the stop operation is performed regardless of the control by the controller 17. (2) If there is no obstacle within the safe stop distance and the brake pedal 13 is stepped on hard, the brake hydraulic pressure control program of the brake device 16 works to stop safely without falling. That is, in accordance with the control signal from the controller 17, the brake hydraulic pressure control program controls the brake hydraulic pressure of the brake device 16 so that the forward inertia moment generated at the time of stop does not exceed the overturning moment of the vehicle state. (3) On the other hand, when a front obstacle is detected by the front obstacle detection sensor 12, the controller 17 performs a safe stop. In other words, if an obstacle enters the safe stop distance of the vehicle such as lift, load, forward tilt angle,
The controller 17 automatically controls the brake operating oil pressure to stop. This prevents the operator from delaying the brake operation and suddenly stepping on the brake and tipping forward. The actual safe stop distance varies depending on the road type, whether the road is wet due to rain, and the condition and type of tires. With respect to these, a means for automatically processing in the program by the sensor and a method for the operator to manually input them on the display panel can be selected, and these are determined by factors such as cost.

[0011]

According to the present invention, during normal traveling, the vehicle can travel without holding down the maximum speed at this time, and at the time of stopping, the controller 17 can safely stop and prevent the vehicle from falling.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

[Explanation of symbols]

1 ... Forklift, 2 ... Car body, 3 ... Front wheels, 4 ... Rear wheels,
5 ... Mast, 6 ... Tilt cylinder, 7 ... Fork, 8 ...
Lifting cylinder, 9 ... Load sensor, 10 ... Fork height detection sensor, 11 ... Forward tilt angle detection sensor, 12 ... Obstacle detection sensor, 13 ... Brake pedal, 14 ... Brake depression amount detection sensor, 15 ... Vehicle speed detection sensor, 16 ... Brake device, 17 ... Controller.

Claims (1)

[Claims] 1. A load detecting means for detecting a lift height load, a lift detecting means, a forward tilt detecting means for detecting a forward tilt angle of a lifting device, a front obstacle detecting means for detecting the presence or absence of a front obstacle, and a vehicle speed. And a controller for controlling the braking force of the braking device, the controller further including a detection unit and a brake depression amount detection unit, and further calculating a distance at which the vehicle can be safely stopped from detection values from these detection units. Industrial vehicle fall prevention device.