JPS59172398A - Controller for stoppage of cargo-handling section of cargo gear - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a surface arrangement for stopping a cargo handling part such as a fork claw at a predetermined lifting height position in a cargo handling device such as a battery forklift truck.

Conventionally, in battery forklifts, pressure oil discharged from a hydraulic pump driven by an electric motor is supplied to a lift cylinder via a flow control valve, and the fork claw is raised and lowered by the lift cylinder. be.

Then, the electric motor is started and stopped by a switch installed in the flow control valve, and the flow rate control valve is manually switched to increase or decrease the flow rate supplied to the lift cylinder to raise the fork pawl (lift height). It controls the speed.

However, with such a control device, in order to stop the fork pawl at a predetermined lifting height position, the operator must visually check the fork pawl and switch the flow control valve, which is cumbersome and time-consuming. However, there is a problem in that the lift cannot be stopped accurately at a predetermined lifting height position.

The present invention was developed in view of the above circumstances, and its object is to provide a cargo handling section stop control device for a cargo handling device that can accurately and easily automatically stop the cargo handling section at a predetermined lifting height position. The goal is to provide the following.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 is an overall explanatory diagram, in which a movable mast 2 is provided along a fixed mast 1 so as to be movable up and down by a lift cylinder 3, and a fork claw 4 serving as a cargo handling section is provided on the movable mast 2 so as to be movable up and down. Conventionally known cargo handling equipment! In addition to configuring the device, first to third deceleration switches 51 are provided on the fixed side (not shown).
+52+5s and 1st to 3rd stop switches 61 + 6
2 +' 63 are arranged facing the movable mast 2 and spaced apart in the vertical direction.

The hydraulic pump 7 is driven by an electric motor 8, and its discharge side 7
It is connected to the lifting chamber 3α of the lift cylinder 3 via an α flow rate control valve 9, and the flow rate control valve 9 is operated by a lever 1o to operate a switching part 9α to control the supply flow rate to increase or decrease. In addition, the switch 11 for 1st speed, the switch 12 for 2nd speed, and the switch 1 for 3rd speed are located opposite the switching part 9α.
3 is arranged, and when the supply flow rate is increased, each switch I
+, 12j+3 is depicted as operating.

Each of the switches 5.6, l l, and 12.13 is connected to the controller 15 by a hand changeover switch 14, and the controller 15 outputs a signal to the chopper circuit 16 provided in the electric circuit 8α of the electric motor 8. It is composed.

In other words, the hand selector switch 14, as shown in FIG.
1st. Second manual changeover switch 17. .

172 can be freely switched to manual position (A), 1st position (c9. 2nd position, 3rd position), and if it is set to manual position (A), the switch 11 for 1st, 2nd, and 3rd speeds.゜1
Only 2.13 is connected, and the 1st, 2nd and 3rd stage positions (su, ←
(If →, the first, second, and third deceleration switches 51~
53 is connected in series to the 2nd and 3rd speed switches 12 and 13,
And 1st. Second. Third stop switches 61 to 63 are connected in series to the single-use switch 11.

However, the first. 2nd manual changeover switch + 71. .

172 in the first stage position, the first deceleration switch 5. is connected in series to the 2nd and 3rd switch 12.13,
The first stop switch 61 is a single-use switch! Can be connected in series to I.

In this state, when the flow control valve 9 is set to the 1st speed position, the 1st speed switch 11 is turned on (..., the first pulse generator 15 of the controller 15 outputs a start signal (short pulse signal) Rx to the chopper circuit 16. The electric motor 8 is driven at low speed.In other words, the first speed switch 11 is
N, OFF switch.

Furthermore, when the flow rate control valve 9 is sequentially operated in the speed increasing direction, the 2nd speed switch 12, the 3rd speed switch 13 are sequentially turned ON, and the 2nd and 3rd pulse generators 15□,
Pulse signals R2 and Rs, which are sequentially longer than 153, are output to the chopper circuit 16, and the electric motor δ sequentially rotates at high speed, increasing the discharge flow rate of the hydraulic pump 7. The lift cylinder 3 extends at high speed,
The fork pawls 4 sequentially ascend at high speed.

Then, the movable mast 2 turns off the first deceleration switch 5□.
When activated, 2nd and 3rd speed switch 1? .

No signal is output from 13, and the first gear switch 11
Since the electric motor 8 is driven at a low speed by the signal from the pump, the flow rate supplied to the lift cylinder 3 decreases and the rate of rise of the fork pawl 4 becomes slow regardless of the operating position of the flow control valve 9.

Then, when the fork pawl 4 further rises, the first stop switch 61 is turned off, and no signal is output from the first speed switch 11, and no pulse is output from the chopper circuit 16, so the electric motor 8 stops. Since the hydraulic motor 7 also stops, the fork pawl 4 stops at that position.

Also, 1st. Second manual changeover switch l'71. When I'7° is set to the second position ← or the third position (→), the second deceleration switch 52, the second stop switch 62, or the third deceleration switch 53. When the switch 63 is turned off, the speed is decelerated and stopped.

Also, 1st. When the second manual changeover switch 17b17t is set to the manual position ((), the deceleration switches 51 to 5
3. Flow rate control valve 9 regardless of stop switch 6□~63
The fork pawl 4 is raised at a speed corresponding to the operating position.

Note that an inverter circuit may be used instead of the chopper circuit I5. In other words, it is sufficient if the power supply to the electric motor 8 is interrupted at a speed corresponding to the input signal.

The present invention is as described above, and the cargo handling section 4'fi can be accurately and easily automatically stopped at a predetermined lifting height position, and the lifting speed of the cargo handling section 4 can be arbitrarily controlled.

[Brief explanation of the drawing]

FIG. 1 is an overall explanatory diagram showing an embodiment of the present invention, and FIG. 2 is a control circuit diagram. 3 is a lift cylinder, 3α is a lift chamber, 4 is a cargo handling section, 7 is a hydraulic motor, 8 is an electric motor, and 9 is a flow rate control valve. Applicant: Komatsu Forklift Co., Ltd. Agent: Masaaki Yonehara Patent attorney: Futada Hama

Claims (1)

[Scope of Claims] Pressure oil discharged from a hydraulic pump 7 driven by an electric motor 8 is supplied to the lifting chamber 3α of the lifting cylinder 3 of the cargo handling section 4 by a flow rate control valve 9, and the flow rate control valve 9 Turns on according to the operating stroke. A plurality of speed stage switches II, 12° 13 are provided to turn off, and the rotational speed of the electric motor 8 can be controlled to be switched to the number of firing stages by the speed stage switches II, 12° 13. A cargo handling section stop control device for a cargo handling apparatus, characterized in that a switch for detecting the lift height of the cargo handling section 4 is also provided, and the electric motor 8 is stopped by a detection signal from the switch.