JPS5823320B2 - Hoisting machine control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a hoisting machine such as an electric hoist or an electric chain block.

Generally, a hoisting machine such as an electric hoist or an electric chain block uses a reversible electric motor, and hoists or lowers a suspended load by rotating the electric motor forward or backward.

In such a hoisting machine, a limit switch is activated to stop the electric motor at the upper or lower limit of the suspended load, thereby ensuring the safety of cargo handling operations.

On the other hand, this type of hoisting machine is equipped with an electromagnetically operated brake to stop the suspended load midway through, and since the electric motor and brake are controlled synchronously, the limit switch is There was a problem in that inserting it into the wafer would complicate the process and require a lot of time for adjustment work to stabilize the characteristics.

SUMMARY OF THE INVENTION An object of the present invention is to propose a hoisting machine control device that has a simplified configuration, reduces adjustment work, and operates stably.

A feature of the present invention is that a reversible single-phase electric motor is connected to a single-phase power source using a control switch so as to rotate in any direction, and the electromagnetic coil is energized to release the brake.
In a hoisting machine that moves a suspended load up and down by winding up or unwinding rigging by rotating the electric motor forward or backward, one end of the hoisting coil of the electric motor is connected to one side of the single-phase power source. a hoisting control switch circuit in which the other end of the hoisting coil is connected to the other side of the single-phase power source via a first switch for hoisting, and one end of the electromagnetic coil is connected to one of the single-phase power sources; The other end of the electromagnetic coil is connected to the other end of the hoisting coil via a second hoisting switch that operates in conjunction with the first switch, and the other end of the electromagnetic coil is connected to the first switch together with the other end of the hoisting coil. an electromagnetic coil drive control circuit that connects to the other side of the single-phase power supply via a Inserted in series into a common circuit consisting of the other end of the hoisting coil, which is a common part with the drive control circuit, the first switch, and the other end of the single-phase power supply,
Two lower limit switches that operate at the lower limit position of the suspended load are provided, and the lower limit switches are inserted into the lowering control switch circuit and the electromagnetic coil circuit, respectively.

Therefore, the operation of the one upper limit switch serves to simultaneously control the winding control switch circuit and the electromagnetic coil drive control circuit.

This will be explained below based on the drawings.

FIG. 1 shows an example of an electric chain block, in which a sprocket 1 is rotated by a reversible electric motor 2 via a speed reduction mechanism 3.

I am made to do so.

A load hook 5 is attached to a link chain 4 wound around a sprocket 1, and the electric motor 2 is stopped by operating a limit lever 6 at the upper and lower limit positions of the load hook 5.

I is an electromagnetically operated brake that is synchronized with electric motor 2 and is energized to release the brake and sprocket 1 (electric motor 2).
is configured to allow rotation of.

FIG. 2 shows a conventional example of an electrical control circuit for an electric chain hoist as described above.

Electric motor 2, two coils 2a, 2b and capacitor 2
Consisting of c.

The common terminal of the coils 2a and 2b is connected to the power supply line 8, and the other end of the coil 2a is connected to the other power supply via the first upper limit switch 6a and the push button switch 9a for raising control. Connected to line 10.

The other end of the coil 2b is the first lower limit. switch 6c
and is connected to the power supply line 10 via a first push button switch 11a for lowering control.

7a is an electromagnetic coil for releasing the brake, and one end is connected to the power line 8.
The other end is connected to the power supply line 1 via a second upper limit switch 6b and a second push button switch 9b for raising control.
Connected to 0.

The second lower limit IJ limit switch 6d and the second push button switch 11b for lowering control are connected in series and connected between the electromagnetic coil 7a and the power line 100.

Note that the upper limit switch 6a t 6b and 6c
t 6 d are interlocked with each other, and push button switch 9 a
t9b and 11a.

11b are interlocked with each other.

In such an electric chain block, the push button switch 9 a t 9 b or the push button switch 11 a.

11b, on the one hand, the motor coil 2a t 2 via the limit switch 6a or 6c.
b, and on the other hand, energizes the electromagnetic coil 7a via the limit switches 6b, 6a.

This releases the brake 7, rotates the electric motor 2, rotates the sprocket, and moves the suspended load up and down.

When the load hook 5 reaches the upper limit and hits the limit lever 6, the upper limit switch 6a is activated.

6b is opened and when the lower limit is reached, the lower limit switches 6c and 6d are opened, deenergizing the electric motor 2 and the electromagnetic coil 1a and stopping them.

Therefore, during the winding operation, the upper limit switch B a t
When 6 b is activated, the coasting distance is almost negligible and the lower limit switch 5 c t is activated.
(If id is activated, the coasting distance to stop will be longer due to the influence of the inertia of the cargo movement.

Therefore, when the upper limit switches 6a and 6b are cut off, the following inconvenience will occur unless both switches 6a and 6b are activated at the same time.

That is, the limit switch 6b is the limit switch 6
If it is released before the limit switch 6a, the brake 7 will suddenly stop while the electric motor 2 is energized, and the limit switch 6a will not be released, and the push button switch 9a for raising control will not be released.
(push closed) If you continue, the motor coils 2a and 2b will burn out.

On the other hand, if the limit switch 6a is opened before the limit switch 6b, the torque of the electric motor 2 disappears, so that the load of the suspended load is lowered.

Therefore, the limit lever 6 returns and the limit switch 6
a closes, the winding operation begins again, and this process is repeated.

Therefore, the upper limit switch $a. 6b needs to be released at the same time, requiring adjustment work.

Since the coasting distance is long during the lowering operation, the above-mentioned inconvenience does not occur.

Next, an electric control circuit for an electric chain block showing a first embodiment of the present invention will be explained based on FIG.

The motor coils 2a, 2b and the capacitor 2c are connected in a capacitor run motor connection.

The common terminal of the coil 2a t 2b is connected to the power supply line 8, and the other end of the coil 2a is connected to the power supply line 1 via the upper limit switch 6a and the first pushbutton switch 9a for raising control.
0, and the other end of the coil 2b is connected to a first lower limit switch 6c and a first push button switch 11a for lowering control.
It is connected to the power supply line 10 via.

One end of the electromagnetic coil 7a for operating the electromagnetic brake is connected to the power line 8.
and the other end is connected to a second push button switch 9 for raising control.
Motor coil 2a and upper limit switch 6 via b
connected between a.

The other end of the power supply coil 7a is connected to the power supply line 10 via a second push button switch 11b for lowering control and a second lower limit switch 6d.

Lower limit switches 6c, 6d, push button switches 9a, 9b for raising control, push button switch 11 for lowering control
a t 11 b are linked.

In the above configuration, the push button switch 9a for raising control,
When 9b is closed, the motor coils 2a, 2b and the electromagnetic coil 7a are energized via the upper limit switch 6a, the brake 7 is released, and the motor 2 rotates.
Rotate sprocket 1.

Wind up link chain 4.

When the load hook 5 hits the limit lever 6 and rotates it clockwise, the upper limit switch 6a opens and the motor coils 2a, y 2b and electromagnetic coil 7a
are blocked at the same time.

Therefore, the winding operation stops immediately. However, the above-mentioned inconvenience does not occur.

Next, when the push button switches 11a and 11b for lowering control are closed, the motor coils 2a and 2b are energized via the first lower limit switch 6c, and the electromagnetic coil 7a is activated by the second lower limit switch 6c.
lower limit switch 6d.

is energized via , causing sprocket 1 to rotate.

Lower link chain 4.

When the lower limit is reached and the limit lever 6 is rotated counterclockwise, the lower limit switch 6 c t 6 d
opens and stops the lowering operation.

In hoisting control, when the upper limit switch 6a is opened, the generated voltage of the motor coils 2a and 2b acts to energize the electromagnetic coil 7a, but since the coasting of the motor 2 is rapidly attenuated by the load, the electromagnetic coil There is little delay in the disappearance of 7a.

Further, in the lowering control, the second lower limit switch 6d, which is electrically independent from the motor coil circuit, is connected to the electromagnetic coil 7a.
The electromagnetic coil 7a is not energized by the voltage generated by the voltage 2b.

In Fig. 4, lower limit switch 6c is also used for lowering control.
This is an example of restricting by .

In this case, the other end of the electromagnetic coil 7a is connected between the motor coil 2b and the lower limit switch 6c via a second push button switch 11b for lowering control.

; In this example, the lower limit switch 6c is activated during the lowering operation.
After the motor coils 2a and 2b are released, the voltage generated by the motor coils 2a and 2b temporarily energizes the electromagnetic coil 7a, which delays the application of the brake 7 and increases the coasting distance, but the limit switch mechanism is simplified. : Effective for applications that do not require high stopping accuracy.

In each embodiment, the push button switches 9a, 9 for raising control are
b and a push button switch 11a for lowering control.

It is preferable to add a mechanical or electrical interlock so that it is not closed at the same time as 11b.

Each embodiment also includes push button switches 9a and 9b.

11a and 11b directly control the motor coils 2a and 2b and the brake electromagnetic coil 7a,
It is clear that the same implementation can be achieved by interposing a relay circuit.

1 As described above, according to the present invention, the hoisting machine can be controlled by inserting one upper limit switch for hoisting restriction into the common circuit that is the common part of the hoisting control switch circuit and the electromagnetic coil drive control circuit. In this way, unstable operation of the device can be eliminated, and the configuration can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a mechanical diagram of an electric chain hoist, FIG. 2 is a conventional control circuit diagram, and FIGS. 3 and 4 are control circuit diagrams showing embodiments of the present invention. 11... Sprocket, 2... Reversible electric motor, 6... Limit lever, 6a...
...Upper limit switch, 6e? 6d... Lower limit switch, 7... Brake, 7a...
. . . Electromagnetic coil, 9a . . . 1st push button switch for raising control, 9b . . . 2nd push button switch for raising control, 11a>11b . . . Push button switch for lowering control.

Claims (1)

[Claims] 1. Connecting a reversible single-phase electric motor to a single-phase power supply using a control switch so that the rotation characteristic is in any direction, energizing the electromagnetic coil and releasing the brake, and rotating the electric motor in the forward or reverse direction. In a hoisting machine that moves up and down to wind up or unwind rigging and lift a load, one end of the hoisting coil of the electric motor is connected to one side of the single-phase power supply, and the other end of the hoisting coil is used for hoisting. a winding control switch circuit connected to the other side of the single-phase power supply through a first switch; and one end of the electromagnetic coil connected to one side of the single-phase power supply and the other end of the electromagnetic coil connected to the first switch. an electromagnetic coil that is connected to the other end of the hoisting coil through a second hoisting switch that is interlocked with the hoisting coil, and further connected to the other end of the single-phase power source together with the other end of the hoisting coil via the first switch; The hoisting coil includes a drive control circuit and one upper limit switch that operates at the upper limit position of the suspended load, and the upper limit switch is connected to the hoisting coil which is a common part of the hoisting control switch circuit and the electromagnetic coil drive control circuit. Two lower limit switches are provided that are inserted in series into a common circuit consisting of the other end, the first switch, and the other end of the single-phase power supply, and that operate at the lower limit position of the suspended load. A hoisting machine control device characterized by being inserted into a lowering control switch circuit and an electromagnetic coil circuit.