JPS59128195A - Controller for operation of electric hoist - 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 [Field of Application of the Invention] The Fusaku 94 relates to an operation control device for an electric hoist and is suitable for application to bamboo electric hoists, electric tension blocks, and the like.

[Prior art]

Conventional according to Figure 2? Explain IJ. Conventionally, there was no inverter with a frequent reset terminal that could mask the inverter output's wakeup pressure using an external signal. Since the falling time ゛I'1 cannot be reduced, the shaded part in Figure 2 of the inverter output voltage will cause mode lock and destroy the inverter, but since the inverter will trip due to overcurrent, a magnetic switch will be used to control the inverter output and mode. The main circuit between them is cut. Therefore, when the brake operation delay time TI in the diagram is longer than the brake operation delay time TI shown in the diagram, the inertia of the contacts of the magnetic switch is large, and the lock current flows, so the operation command is issued for a time longer than r1, which is not affected by the inertia. An operation command prohibition time t is set using an off-delay timer so that the command is not accepted.

Therefore, there is a drawback that a substantial inching operation cannot be performed.

[Purpose of the invention]

The purpose of the present invention was to eliminate the above-mentioned drawbacks, and at the same time as an inverter output stop command is input to the operation control device inverter, the forced output stop circuit of the inverter is activated. The purpose of the present invention is to provide an electric hoisting machine that can perform inching operation.

[Summary of the invention]

In the conventional speed control of the hoisting machine using an inverter, it took about 2 seconds for the inverter output to become zero after an inverter output stop command was input, and the inching operation of the hoisting machine was not possible.

The present invention uses an inverter with a forced reset circuit that makes the inverter output zero in a short time, and when an inverter output stop command is input to the inverter, the inverter output is made zero in a short time, and the inching operation of the hoist is stopped. It made it possible.

[Embodiments of the invention]

An embodiment in which the present invention is applied to a hoist will be described below with reference to FIG.

The inverter 8 operates according to the voltage applied to the operating force 0.
1 The frequencies of the outputs U, V, and W of the inverter 8 change. Further, by setting the operation input FkLt of the inverter 8 to zero potential, the phase order of the output of the inverter 8 can be changed and the connected hoisting sea bream driving electric waJ can be rotated forward or reverse. About this inverter 8, 8. A power supply 1 is connected to T, and a hoisting drive electric motor 10 is connected to outputs U, V, and W of the iso/<-ta 8.

The push button control circuit is connected to S and T of power supply 1, and these 8,
Between 1 and 1, there is a push button switch 5 for upper and a relay coil 2 for earth.
are connected in series, and a normally open contact RA 3-a of the lower relay coil 3 is connected in parallel with the upper push button switch 5. Further, between 8.1 and 8.1, a lower push button switch 6 and a lower relay coil 3 are connected in series, and between 8.1 and 8.1, normally open contacts R and 2- of the upper relay coil 2 are connected in series. c and the timer coil 4 are connected in series. Also, S.

1, a brake 9 is connected in series with the timer contact 4a.

Between H and L of the inverter 8, the normally open contact 2-8 of the Doyo relay 2 and the variable resistor 7 are connected in series, and the voltage divided by the variable resistor 7 is connected to the inverter 80M. applied. In addition, L-8 of the relay 3 is connected through the normally open contact R32bf, and L and R are connected through the normally closed contact R2bt of the relay 2. ing.

One embodiment of the above configuration will be described.

First, by pressing the upper push button 5, the υ upper relay coil 2 is energized, and the normal Sl contacts, 2-C and R, 2-a are closed, 2-b is open, and kLy2-a is By closing, the inverter operation input is suddenly applied to M of 8, and a voltage divided by L-H is applied by variable resistor 7, and the normally closed contact R
, 2-b, Yoshi L and Bon.

is opened, a voltage at the frequency set by the variable resistor 7 is output to the inverter 80 outputs U, V, and W, and the hoisting motor 10 rotates. At this time, the normally open contact RA2-
When C is closed, the timer 4 is excited, and after a certain period of time, the timer contact 4a is closed, voltage is applied to the brake 9, and by releasing the brake 9, the electric paddle 10 of the P hoisting machine is rotated. is allowed.

To rotate the hoisting motor 10 in the opposite direction under the above-described control, this is accomplished by pressing the lower push button 6. When the lower push button 6 is pressed, the lower relay coil 3 is energized and the normally open contact B-a 3-a is activated.

R-a3-b closes. What is different from the above case is that the relay 3 operates extra, the normally open point 3-b closes, and the inverter 8's output phase sequence is reduced to is different from the case described above, so the hoisting electric machine 10 is reversed.

The operation described above will be explained with reference to FIG.

An operation command is input to the inverter 8 by pressing the lower push button 5 or the lower push button 6. When the operation command is input to the inverter 8, the forced reset is canceled.

The output voltage of the inverter 8 starts at P, the brake 9 is released after the time set by the timer 4, the hoisting motor 10 starts rotating at t, and winds at the rotation speed determined by the setting value of the variable resistor 7. The upper electric motor 10 continues to rotate. Since the inverter output voltage starts from zero at startup, the timer 4 applies the brakes to prevent the load from falling until the torque of the electric machine 10 reaches a voltage that can lift the rated load. The setting time is delayed.

When the upper push button 5 or the lower push button 6 is set to 10FF, the relay 2 or 3 is turned off, the brake 9 is activated, and the hoisting motor 10 is stopped. Further, the terminal of the inverter 8 to which the forced reset command is input is short-circuited to L. When the forced reset terminal R1 is short-circuited to L, R is dropped to zero potential, and therefore the inverter output voltage is dropped to zero. Due to this, #! Output fall time p time T as explained in Figure 2
There is no need to prevent the next operation from being accepted during period b. In addition, in Figure 1, L and R1 are the normally closed contacts R of relay 2.
,, connected via 2-bQ, p, operation command is OFF
At times, the forced reset terminal 几 is always shorted to L to ensure that the inverter output becomes zero. Here, the 9 hours Tb of inverter output fall is the rest time T during drive operation.
+ It is set to become shorter.

As described above, when the hoisting motor 10 is controlled by the inverter 8, when the operation command for up, down, etc. is turned off, the output from the inverter 8 becomes OFF, so the next up, down, etc. operation can be performed immediately. can. Also, the operation command is OFF.
At the time of , the output voltage is short-circuited to L, H+a is routed to zero potential, and no output is output from the inverter 8.

According to this embodiment, in the speed control of the hoisting machine by the inverter 8, the upper and lower presses a5, 6t-ON are turned on, and the output of the inverter 8 causes the hoisting motor wJmx to be turned on.

After the inverter rotates, when push buttons 5 and 6'1 are turned OFF, the inverter output voltage immediately becomes zero, making it possible to perform drive and sudden reverse operations, which improves the operability of hoisting machines, etc. that have inverter output voltage. .

FIG. 4 will be explained. A three-phase or mixed power source 1 enters the converter module 11, is converted to direct current, and is connected to the inverter module 13 via a smoothing capacitor 12t. Further, the inverter module 13 converts the direct current into a variable current, which is connected to the inverter outputs U, V, W, and the hoisting machine 111Ib 1O. The voltage between H and L is divided by a variable resistor 7 for setting the inverter output frequency and inputted to M. Assuming that the series relay 2 is energized by the upper push button 5, the voltage that is divided when R2-a is closed is M.
From there, it passes through an acceleration circuit with a time constant consisting of a resistor and a capacitor and enters the Ij8117 dedicated to the p1 mode. LS117 exclusively for Modol has ROM 18, microcomputer 19. The RAM 20 is connected via a pass line 21t, and when the voltage is divided by the variable resistor 7 and inputted to M, the pace movement module 14 is outputted from the moder dedicated LS 117, and the base drive module 14 is
are outputted to the base of each inverter module 13, thereby becoming the inverter outputs u, V, and W.

- When the upper press f15t is turned off, Rr and 2-a are opened, and the deceleration circuit 16 having a time constant consisting of a capacitor and a resistor is connected to the moder exclusive LS117. In this embodiment, due to the nature of the electric hoist, when the operation command is turned OFF, the hoisting motor is no longer energized, and at the same time, the rotation of the brake 9 is stopped, so the inverter output voltage is decelerated. By changing the constant of the deceleration circuit 16, the time Tb is made shorter than the rest time TI during drive operation, and when the operation command is OFF, the forced reset terminal R,'1i
-L is short-circuited to bring the potential to zero, thereby dropping the inverter output to zero.

According to the above, when the p1 up and down commands are OFF, the inverter metalworking 9 time Tb is short, and therefore the inverter output immediately becomes zero, and the down time TI during increments and movements is also Tb.
Since it is short, it is possible to move on to the next operation immediately, and drive operation and sudden reverse operation are also possible.

〔Effect of the invention〕

According to the present invention, when the speed of an electric hoist is controlled by an inverter that varies the power frequency, a forced reset is performed by the control device inverter at the same time as an inverter output stop command is input, and the inverter output is immediately reduced to zero. As a result, when the hoist is controlled by an inverter and continuously variable speed control is performed, inching operation becomes possible and work efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a control circuit diagram of an operation control device according to the present invention, and FIG.
FIG. 3 is an example of a time chart of the electric hoist according to the present invention, in which the operating time of the electric hoist is shown on the horizontal axis;
FIG. 4 is a block diagram of the inverter. 1...Power supply, 2...Relay for rising circuit, 3...1
Relay for descending circuit, 4... Relay with delay circuit for brake, 5... Push button for rising, 6... Push button for descending, 7...
Speed setting variable resistor, 8...control device inverter,
9... Pre-mochi l Mouth 2nd figure F'shi - ~ 1 treat

Claims (1)

[Claims] 1. It takes a short time T to receive the operation command for hoisting or lowering.
- It has a soft start and stop function in which the output voltage rises for a while and then falls for a short time Tb by turning off the command, and can mask the output voltage by an external signal only for the duration of the external signal. In an electric hoisting machine that has an inverter having a forced reset terminal with a function, a hoisting mode that can vary the speed according to the variable voltage and frequency output of the inverter, and a brake that operates when the operation command is OFF. When the operation command is OFF, the signal is always input to the external reset terminal, and the short fall time Tb'f of the inverter output voltage is set as short as the pause time T+ during the inching operation of winding or lowering. An operation control device for an electric hoisting machine.