JPH0683583B2 - Brake motor operation control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a multipolar stator winding for rotating a basket-type rotor motor at a low speed, a small polarity stator winding for rotating at a high speed, and a magnetic field generated by an electric current. The present invention relates to an operation control device for a braking electric motor that includes a braking device that is released by.

[Prior art]

Conventionally, as this type of technology, there is one disclosed in, for example, Japanese Patent Publication No. 58-29704. The braking electric motor as described above is used as a hoisting electric motor such as a hoisting machine, and is operated at a low speed when starting up and down, and then switched to a high speed for operation. In this way, it is used by switching from low speed to high speed, but when the number of poles of the multi-polar stator winding for low speed is large, the winding current is large and the armature current is small, so the strength of the magnetic field generated by it is also weak. There is a problem that the ratio of high speed and low speed cannot be increased so much because the motive cannot be released. As a countermeasure against this, conventionally, as shown in Japanese Patent Publication No. 58-29704 (see the circuit diagram in FIG. 3), a small-polarity stator winding is temporarily provided in parallel with the multi-polarity stator winding when the braking motor is started. A current is also supplied to increase the magnetic field for releasing the brake.

[Problems to be Solved by the Invention]

However, as described above, in the method of temporarily supplying parallel current to the multi-polarity stator winding and the small-polarity stator winding in parallel to increase the magnetic field for releasing the brake, the small polarity on the high speed side at the time of start-up. Since the electric current is supplied also to the stator winding, the electric motor tries to rotate at a high speed, which causes a shock.

There is also a problem that the high speed side is regeneratively braked at the moment when the simultaneous energization is switched to the low speed, causing a shock. Especially in hoisting machines, this shock is an important problem.

The present invention has been made in view of the above points, and an object of the present invention is to provide an operation control device for a braking motor that does not cause a shock at the time of startup and switching from high speed to low speed.

[Means for Solving the Problems]

In order to solve the above problems, the present invention provides a cylindrical cage rotor,
In an operation control device for a braking motor, which comprises a multipolar stator winding, a small polar stator winding, and a brake released by a magnetic field generated by an electric current, a current is supplied to the multipolar stator winding at startup. A control means is provided for supplying the current to the small-polarity stator winding and temporarily supplying a current having a phase opposite to that of the current supplied to the multi-polarity stator winding.

[Action]

By configuring the operation control device for the braking electric motor as described above, the braking electric motor is in the anti-phase braking state at the time of startup.
No shock occurs at startup. In addition, when switching from high speed to low speed, shock caused by regenerative braking does not occur unlike the conventional case.

〔Example〕

 An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram of an operation control device for a braking motor according to the present invention. In the figure, M is a two-stage braking motor, U, V and W are three-phase AC power supplies, MD1 is a hoisting relay, MC2 is a lowering relay, MC3 is a low speed relay, MC4 is a high speed relay, and Tr is a Tr. Is a transformer, T is a timer, R is a reverse phase braking relay, PB1 is a hoisting push button switch, and PB2 is a hoisting push button switch.

The two-speed braking motor M is a terminal of a multi-polar stator winding for low speed.
It has terminals U1, V1, W1 and terminals U1, V2, W2 of the small polarity stator winding for high speed. The hoisting push-button switch PB1 and the hoisting-down push button switch PB2 are two-step push button switches, and the low speed can be set in the first step and the high speed can be set in the second step. .

In the operation control device having the above circuit configuration, in the case of hoisting operation, when the hoisting push-button switch PB1 is pushed one step, the normally open contact PB1-1 closes and the normally closed contact PB1-3 opens.
This activates the hoist relay MC1 and its normally open contact MC1.
-1, Close MC1-2. When the normally open contact MC1-2 is closed, the low speed relay MC3 operates to close the normally open contact MC3-1. As a result, the terminals U1, V1, W1 of the two-speed braking motor M are
Through this, current is supplied from the power supplies U, V, W to the multi-polarity stator winding for low speed. At the same time, the normally open contact MC1-2
Is closed, the timer T operates to operate the reverse phase braking relay R for a short time until the normally closed contact opens, and the normally open contact R-1 closes. As a result, the two-speed braking motor M
From the terminals U1, V2, W2, a current having a reverse phase to the current supplied to the multi-polar stator winding is supplied to the high-speed small-polarity stator winding.

As a result, current is supplied to the small-polarity stator winding at the same time as the multi-polarity stator winding, so that the armature current becomes large and the magnetic field for releasing the brake becomes large. Further, since the two-speed braking electric motor M is in the state in which the antiphase braking is applied,
The two-speed braking motor M will start smoothly without shock.

When a short time (for example, 0.1 to 0.2 seconds) set in the timer T elapses, the timer T operates and its normally closed contact T-1 opens, whereby the anti-phase braking relay R becomes inoperative and its normally open state. Since the contact R-1 is opened, the two-speed braking motor M
The reverse-phase current supplied to the small-polarity stator winding of is cut off,
The two-speed braking motor M rotates at a low speed in the state where the anti-phase braking is released.

When the hoisting push-button switch PB1 is pushed to the second stage in this state, the normally-open contact PB1-1 and the normally-open contact PB1-2 are closed, and the high-speed relay MC4 operates, and the normally-open contact MC4-1. And the normally closed contact MC4-2 are opened. As a result, current is supplied from the power sources U, V, W to the small-polarity stator windings of the two-step braking motor M, and the two-step braking motor M rotates at high speed.
At the same time, by opening the normally closed contact MC4-2,
Since the low speed relay MC3 does not operate and opens its normally open contact MC3-1, the current of the multipolar stator winding is cut off.

When the hoisting push-button switch PB1 is moved from the second stage to the first stage, the normally open contact PB1-2 opens, so the high-speed relay M
C4 becomes inoperative, and its normally open contact MC4-1 is opened and at the same time the normally closed contact MC4-2 is closed. As a result, the current of the small-polarity stator winding of the two-step braking motor M is cut off and at the same time,
When the normally closed contact MC4-2 is closed, the low speed relay MC3
Is operated to close the normally open contact MC3-1, current is supplied to the multi-polar stator winding of the two-step speed braking electric motor M to rotate at a low speed.

Next, for lowering operation, lowering pushbutton switch PB2
When is pressed to the first step, the normally open contact PB2-1 closes and the normally closed contact PB2-3 opens. As a result, the lowering relay M
C2 operates and closes its normally open contacts MC2-1 and MC2-2. When the normally open contact MC2-2 is closed, the low speed relay MC3 operates to close the normally open contact MC3-1. As a result, the power source U, V,
Current is supplied from W. At the same time, the normally open contact M
When C2-2 is closed, the timer T operates and the reverse phase braking relay R operates for a short time until the normally closed contact opens, and the normally open contact R-1 closes. As a result, the high-speed small-polarity stator winding of the two-stage braking motor M is supplied with a current having a phase opposite to the current supplied to the multi-polarity stator winding.

Since currents are simultaneously supplied to the small-polarity stator windings and the multi-polarity stator windings, the magnetic field for releasing the brake is large as described above, and the two-step speed braking motor M was subjected to antiphase braking. As described above, the two-stage braking electric motor M can be smoothly started without shock, as in the case of winding.

When the short time set in the timer T elapses and the timer T operates, the normally closed contact T-1 opens, and the reverse phase braking relay R
Becomes inoperative and its normally-open contact R-1 opens, so that the negative-phase current supplied to the small-polarity stator winding of the two-step braking motor M is cut off, and the two-step braking motor M becomes anti-phase braking. Rotates at a low speed when is released.

When the push-down push-button switch PB2 is pushed to the second step in this state, the normally-open contact PB2-1 and the normally-open contact PB1-2 are closed, and the high-speed relay MC4 operates, and the normally-open contact MC4-1. And the normally closed contact MC4-2 are opened. As a result, current is supplied from the power sources U, V, W to the small-polarity stator windings of the two-step braking motor M, and the two-step braking motor M rotates at high speed. At the same time, by opening the normally closed contact MC4-2, the low speed relay MC3 becomes inoperative and its normally open contact MC3−
By opening 1, the current in the multipolar stator winding is cut off.

When the lowering push-button switch PB2 is moved from the second stage to the first stage, the normally open contact PB2-2 opens, so the high-speed relay M
C4 becomes inoperative, and its normally open contact MC4-1 is opened and at the same time the normally closed contact MC4-2 is closed. As a result, the current of the small-polarity stator winding of the two-step braking motor M is cut off and at the same time,
When the normally closed contact MC4-2 is closed, the low speed relay MC3
Is operated to close the normally open contact MC3-1, current is supplied to the multi-polar stator winding of the two-step speed braking electric motor M to rotate at a low speed.

In the figure, SW1 is an overwinding prevention limit switch, SW2 is an overwinding prevention limit switch, and NR is a reverse rotation prevention relay.

〔The invention's effect〕

As described above, according to the present invention, the current is supplied to the multi-polar stator winding at the time of start-up, and the current opposite to the current temporarily supplied to the multi-polar stator winding is supplied to the small-polar stator winding. Since the control means for supplying the phase current is provided, the following excellent effects can be obtained.

(1) Since the braking motor is in the anti-phase braking state at startup,
No shock will occur when starting.

(2) In addition, since a current is temporarily supplied to the multi-polarity stator winding and the small-polarity stator winding at the time of start-up, a large magnetic field for releasing the braking can be obtained. It is possible to increase it.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an operation control device for a braking motor according to the present invention. In the figure, M: 2-step speed braking motor, MC1: hoisting relay, MC2: hoisting relay, MC3: low speed relay, MC4
...... High-speed relay, PB1 …… Hoisting pushbutton switch, P
B2: Push-down switch for unwinding, T: Timer, R:
Reverse phase braking relay.

Claims (1)

[Claims] 1. An operation control device for a braking electric motor comprising a cylindrical cage rotor, a multipolar stator winding, a small polar stator winding, and a brake released by a magnetic field generated by an electric current. Control means for supplying a current to the multipolar stator winding at the time of start-up and for temporarily supplying a current having a phase opposite to that of the current supplied to the multipolar stator winding to the small polarity stator winding An operation control device for a braking motor, characterized by being provided with.