JPH11255085A - Brake device for lift truck - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely perform the operation for stopping a car body from a position on a lifter by providing an operating device of a lifter with an electro magnetic auxiliary brake for releasing the braking by a main brake in the operation and for making the operation of the main brake free in the non- operation. SOLUTION: Brake operation of a lift truck is performed by the manual force with a pedal from a driver's seat provided in a car body, or performed from an auxiliary operating device 9 provided in a lifter 6 through a solenoid type switch. When a worker exists on the lifter 6, the worker is mainly engaged with the picking work, and at this stage, the car body is ordinarily travels at a low speed. Consequently, even in the case where the brake operation from the lifter is performed by the solenoid turning on/off operation, a shock to be generated by stopping the vehicle is restricted small. Since both the main brake of the driver's seat of the car body and the auxiliary brake on the lifter work as a dead-man type brake, safety at the time of picking work and the load carrying work inside of a warehouse can be realized.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a brake device for a lift truck such as a forklift.

[0002]

2. Description of the Related Art In order to facilitate picking work from a warehouse rack, the lift truck is provided with a device for operating a vehicle body on a lifter that carries a load and moves up and down separately from a normal driver's seat. There is one provided in. By operating this device, the operator performs the picking operation on the lifter and controls the traveling of the vehicle body directly from the lifter. Therefore, in such a lift truck, a brake device for stopping the running of the vehicle body is also required on the driver's seat and on the lifter.

[0003] The above-mentioned auxiliary driving device for picking is particularly often applied to a reach-type forklift, and a brake device in a body driver's seat of this type of forklift applies a brake when an operator does not operate, that is, a so-called forklift. What is called a deadman type brake is widely adopted.

[0004] Specifically, when the operator is stepping on the pedal in the driver's seat, the braking of the drive wheels is released and the vehicle can run, and the brake is automatically applied when the pedal is released. The running of the vehicle body is stopped.
The operator freely operates the pedal depressing force to smoothly move and stop the vehicle body, thereby achieving safe and smooth transportation of the load.

[0005]

When such a driver-side brake device is a deadman type brake, providing an auxiliary brake device to the lifter has the following problems.

For example, if the lifter is a brake device using mechanical means such as a pedal type, mechanical connection between the lifter that moves up and down and the drive wheels on the vehicle body is not easy, and restrictions on the installation location and the like are large. . There is also a danger that the pedals may be accidentally depressed during the picking operation, causing the vehicle body to suddenly start running.

Accordingly, it is conceivable that the brake device on the lifter side is constituted by electromagnetic means. In this case, however, the operation is a simple ON / OFF operation. Free control of the braking force by the vehicle body-side brake device is lost, and it becomes difficult to smoothly operate the vehicle from the driver's seat. An object of the present invention is to solve such a problem.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a lift truck provided with a driving operation device for operating the traveling and stopping of a vehicle body in a driver seat of the vehicle body and a lifter provided on the vehicle body, respectively. The driving operation device for the vehicle body is provided with a deadman-type main brake that is manually operated and brakes the driving wheels of the vehicle body when not operating, and the driving operation device for the lifter releases the braking by the main brake during operation to release the main brake. A brake device for a lift truck, comprising an electromagnetic auxiliary brake for freeing the operation of the main brake during operation is proposed.

When the operator operates the vehicle body on the lifter, when the auxiliary brake is operated (ON), the braking of the main brake on the vehicle body side is released, and the vehicle body is ready to run. Not operated for picking work (OFF)
In this case, the operation of the main brake, which is a deadman type brake, becomes free, and the vehicle body maintains a stopped state.

When the operator performs a driving operation in the driver's seat of the vehicle body, the main brake is released from the operation of the auxiliary brake and is free because the auxiliary brake is not operated. Thus, the main brake can be freely controlled and operated, and the operation of the deadman type brake is also guaranteed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to examples.

[0012]

1 and 2 show a lift truck according to the present invention. This lift truck is based on a reach-type forklift driven by a battery and is supplemented with an auxiliary driving device.

FIG. 1 shows the entire side surface of a lift truck. A driver's seat 2 and a main operation device 3 for driving operation of the vehicle body 1 are provided at a rear portion of the vehicle body 1. A movable mast 4 is provided upright at the front of the vehicle body, and a lifter 6 having a fork 5 is provided so as to be able to move up and down along the mast 4. P is a pallet mounted on the fork 5, and 7 is a head guard for protecting the operator on the driver's seat 3 from falling objects.

When a worker M picks up a required load from a shelf in a warehouse, the worker M stands on the pallet P as shown in the figure and rises together with the lifter 6 to a target shelf.
Reference numeral 8 denotes a guard bar for preventing the worker from dropping from the lifter at this time, and is provided on the lifter 6 so as to be pivotable.

FIG. 2 shows a front view of the lifter 6, and an auxiliary driving operation device 9 on the upper portion of the lifter 6 for the worker M on the pallet P to operate the vehicle body 1 in the rearward direction of the vehicle body 1. Is provided. Reference numeral 10 denotes a lifting / lowering operation device for the lifter 6 disposed beside the auxiliary operation operation device 9.

FIG. 3 is a view showing the brake device and its operation in the two driving operation devices 3 and 9 described above. In the drawings, white arrows indicate the directions in which the respective springs are urged.

In FIG. 1, reference numeral 11 denotes a driving wheel of the vehicle body 1, and 12 denotes a motor for rotating the driving wheel 11.
A disk plate 14 is fixed to the upper end of the second rotating shaft 13, and two brake disks 15, 15 are arranged on the sides of the disk plate 14 so as to sandwich the plate 14 from above and below.

The disks 15, 15 are pivotally supported at their ends 16 so as to be openable and closable with each other, and are urged by springs 17, 17 to press against the plate 14. Cam 1 between both disks 15
8 is rotatably supported by a shaft 19 provided on the vehicle body 1, and a long arm 20 is fixed to the cam 18.

When the arm 20 is inclined leftward in the drawing as shown in FIG. 3, the discs 15, 15 press the plate 14 from above and below by the urging force of the springs 17, 17 and rotate the plate 14 by friction. To stop. If the arm 20 is tilted to the right in the drawing, the cam 19 opens the disks 15, 15 against the force of the springs 17, 17, so that the plate 14 becomes rotatable.

Next, a description will be given of a main brake 21 provided in the main driving operation device 3 of the driver's seat 2 for turning the arm 20 described above.

Reference numeral 22 denotes a pedal provided on the floor of the driver's seat 2 of the vehicle body 1. The pedal 22 is supported by a shaft 23 and urged upward by a spring 24. The pedal 22 is L-shaped when viewed from the side, and the upper end thereof is rotatably connected to the arm 20 by shafts 25 and 26 and a bar 27. 28 is a stopper for the pedal 22.

Therefore, normally, the pedal 22 is
4, the brake disc 15 is strongly pressed against the disc plate 14 from above and below because the arm 20 is in a state of being inclined to the left in the drawing. Then, the vehicle body 1 is stopped by braking the rotation of the drive wheels 11.

When the operator steps on the pedal 22, the arm 2
Numeral 0 inclines rightward in the drawing about the shaft 19, and the cam 18 rotates clockwise to separate the brake disks 15, 15 from the disk plate 14. Thereby, the motor 12
Is rotatable, driven by the driving operation from the main driving operation device 3 described above, and rotates the drive wheels 11 to cause the vehicle body 1 to travel. If the pressing force of the pedal 22 is appropriately controlled, the discs 15 and 15 and the plate 14 can be controlled.
The contact force with the can be adjusted freely.

Next, the auxiliary driving operation device 9 for the lifter 6
Will be described.

An L-shaped brake lever 31 is provided on the vehicle body 1 so as to be pivotable about a shaft 32. The brake lever 31 is provided on the auxiliary driving operation device 9. The brake lever 31 is biased in the counterclockwise direction by a spring 33 provided on the vehicle body, and a forked bracket 34 is integrally fixed below the lever 31.

Further, a limit switch 35 is provided in the operation device 9 corresponding to the lower part of the lever 31, and a plunger 36 of the switch 35 is sandwiched in the bracket 34.

Reference numeral 37 denotes ON / OFF of the limit switch 35.
This is a rotary solenoid that is operated by turning it off, and is arranged above the arm 20 described above. The rod 38 which is turned by the excitation of the solenoid 37 is
It is urged to the left in the drawing by a spring 39 provided on the vehicle body side, and abuts against a stopper 40 to stop.

In the normal state shown in FIG. 3, since the limit switch 35 is OFF, the solenoid 37 is in a non-excited state. At this time, since the rod 38 is located on the left side of the drawing and is separated from the arm 20 by a predetermined distance, the vehicle body 1 remains stopped unless the pedal 22 is depressed. At this time, the arm 20 is connected to the rod 3
8, the arm 20 is inclined rightward in the drawing as described above, and the discs 15 and 15 release the plate 14, so that the vehicle body 1
Is ready to run.

When the operator depresses the lever 31 against the force of the spring 33, the limit switch 35 is turned on, the solenoid 37 is turned on, and the rod 38 turns rightward in the drawing. As a result, the tip of the rod 38 comes into contact with the arm 20 and forcibly tilts it to the right.
The discs 15 and 15 release the plate 14 even if the vehicle is not depressed, and the vehicle body 1 is ready to run.

In the figure, reference numeral 41 denotes a steering device for the vehicle body 1 provided in the auxiliary driving operation device 9, which has a known joystick structure. The steering device 41 is provided immediately next to the brake lever 31. When the operator grips the pole-shaped steering device 41, the hand is pressed against the hand and the brake lever 31 naturally resists the force of the spring 33. The vehicle body 1 is set so as to be turned downward and the vehicle body 1 can be driven.

As described above, in the lift truck according to the present invention, the brake operation is manually performed using the pedal 22 from the driver's seat of the vehicle, and the auxiliary driving operation device 9 in the lifter 6 is operated.
From there, the brake operation of the vehicle body is performed via an electromagnetic switch. When the worker is on the lifter 6, it is mainly engaged in picking work, and at this time, the vehicle body is usually
Running at low speed. Therefore, even if the brake operation from the lifter 6 is an electromagnetic ON / OFF operation, the vehicle 1
The shock caused by the stoppage is small and does not cause any practical problems.

In the lift truck of the present invention, when the pedal 22 and the brake lever 31 are operated, the vehicle body 1 can run, and when not operated, the vehicle body 1 is braked and stopped. That is, both the main brake of the vehicle body driver's seat and the auxiliary brake on the lifter act as deadman type brakes, so that safe picking and cargo transporting work in the warehouse can be realized.

As described above, according to the present invention, the brake operation can be freely performed from the vehicle body driver's seat, and the vehicle body can be reliably stopped from the lifter. In addition, the function of the deadman-type brake on the vehicle body driver's seat side is not impaired, and extremely safe work in the warehouse is enabled.

[Brief description of the drawings]

FIG. 1 is a side view of a lift truck according to the present invention.

FIG. 2 is a front view showing a lifter.

FIG. 3 is a schematic diagram for explaining the brake of the present invention and its operation.

[Explanation of symbols]

 1: vehicle body 2: driver's seat 3: main driving operation device 6: lifter 9: auxiliary driving operation device 11: drive wheel 12: motor 21: main brake 22: pedal 30: auxiliary brake 31: brake lever 35: limit switch 37: Rotary solenoid

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B66F 9/24 B66F 9/24 Z

Claims (1)

[Claims] 1. A lift truck having a driver's seat on a vehicle body and a lifter provided on the vehicle body and a driving operation device for operating the running and stopping of the vehicle body, respectively, wherein the driving operation device of the vehicle body is manually operated. A deadman-type main brake that brakes the drive wheels of the vehicle body when not operated is provided, and the lifter driving operation device releases an electromagnetic brake that releases the main brake when operated and frees operation of the main brake when not operated. A lift truck brake device comprising an auxiliary brake of a type.