JPH08126362A - Motor control means for battery powered hoist equipment - Google Patents

Abstract

PURPOSE: To obtain a control means for ensuring normal operation regardless of the load by eliminating the functional deterioration of a drive motor due to generation of regenerative current. CONSTITUTION: A resistor 3 for treating an excessive regenerating current exceeding the acceptable capacity of a battery 2 generated during lowering drive motion through a motor 1 is connected, along with an excessive regenerating current detector (meter relay 5) for actuating the resistor 3 upon detection of an excessive regenerating current, between the armature of a battery 2 powered motor 1 and a forward/reverse switching circuit (a, b) inserted into a circuit for feeding power to the armature 1a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control means for normally operating a hoisting drive motor of a lifting machine which uses a battery as a power source.

[0002]

2. Description of the Related Art Generally, a motor operated by an AC power source is adopted as a driving means of a hoisting machine used for hoisting heavy objects. A commercial power source is mainly used as the AC power source. However, when the installation environment of the lifting machine is in a condition where commercial power cannot be used, for example, in a mobile device in which the range of action is not specified, or in a device in which a cable or trolley wire is installed and power cannot be supplied, It is necessary to take measures such as driving by an internal combustion engine or installing a generator separately and using it as a power source.

[0003]

However, in order to operate the generator, it is still necessary to drive the engine, and its operation is accompanied by generation of exhaust gas and deterioration of the environment due to exhaust noise. Especially when installed and used in a poorly ventilated state, unless the exhaust gas exhaust equipment is fully equipped, the work environment is deteriorated and problems occur in terms of occupational safety and health.

Therefore, a method of using a battery as a clean power source can be considered. Of course, it is well known that a battery-driven motor is used as a drive source that moves laterally like an electrically driven automatic vehicle. However, when a battery is used as a power source for a device in which a load acts in the vertical direction, such as a hoist of a hoist, the hoist drive motor is driven to drive the load during load lifting operation. A phenomenon occurs in which the motor is positively rotated beyond the required number of rotations. As a result, regenerative current is generated and flows into the battery that is the power source. However, I have learned that this regenerative current cannot be directly received by the battery and hinders the drive function of the drive motor, making it impossible to normally unload the load.

The phenomenon in which the generation of such a regenerative current hinders the drive function of the motor is such that the load acting on the motor of the lifting machine during the unloading operation becomes large and the regenerative current generated exceeds the capacity of the battery. If so, an excessive current will be generated, the driving rotation of the armature will be gradually accelerated, and the braking torque or more will be exceeded, so that the suspended load cannot be stopped. Therefore,
Lifting work becomes difficult.

The present invention solves such a problem and
An object of the present invention is to provide a control means capable of eliminating the functional damage of the drive motor due to the generation of a regenerative current due to the action of a load such as the above-mentioned unloading operation, and performing a normal operation regardless of the load.

[0007]

SUMMARY OF THE INVENTION The present invention, which is configured to achieve such an object, provides a forward / reverse switching circuit in a circuit for supplying power to an armature of a battery-powered motor and the armature. During the period, a resistor for processing an excessive regenerative current that exceeds the allowable battery receiving amount of the regenerative current generated at the time of lowering drive by the motor, and a detection of the excessive regenerative current that activates the resistor when the excessive regenerative current is detected. It is characterized by providing a container.

[0008]

According to the hoisting motor control means of the battery-powered hoisting machine of the present invention constructed as above, when the motor is driven in the hoisting direction, the force of gravity added to the driving force for lowering the load is applied. If the regenerative current generated by the acceleration gradually increases the rotation of the armature and exceeds the capacity of the battery, the resistor that processes the excessive regenerative current by detecting the excessive regenerative current in the power supply circuit Is operated, the excess regenerative current is converted into thermal energy by the resistor and consumed, and the amount of current supplied to the armature is kept steady to enable normal driving. It should be noted that during the winding operation of the motor and during the ascending / descending operation in the state where the regenerative current is small, the resistor is kept in the inoperative state and functions normally.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hoisting motor control means for a hoisting machine using a battery as a power source according to the present invention will now be described with reference to the drawings.

FIG. 1 shows a control circuit which is an embodiment of the hoisting motor control means according to the present invention. In this embodiment, a DC shunt winding motor is used as the motor 1, and forward / reverse phase switching circuits a and b are provided in the circuit connecting the battery 2 to the armature 1a of the motor. A short circuit c is provided in the circuit from the normal / reverse phase switching circuits a and b to the armature 1a, and the short circuit c is operated by the resistor 3 and the meter relay 5 for detecting excess regenerative current. The device 5'is provided in series. A meter relay 5 is provided as a detector for detecting an excessive regenerative current between the short circuit c and the normal side of the armature circuit. In the figure, reference numeral 6 is a main switch, 7 is a hoisting operation switch, 8 is a hoisting operation switch, and 1b is a motor coil.

The control circuit having such a configuration is used by being incorporated in a control unit of a hoisting machine that operates by using a battery as a power source, for example, an electric motor for driving a hoisting drum in a DC electric hoist. The basic structure of the hoist may be a conventionally known structure.

The control means constructed in this way is incorporated into a control unit of a winding drum driving electric motor (not shown), so that the winding operation switch 7 is turned "ON" to drive the motor 1 in the winding direction. A current flows in the armature 1a in the direction of the arrow A, and the armature 1a is rotated normally to drive the winding drum normally. When the lowering operation switch 8 is operated to "ON", the forward / reverse phase switching circuits a and b are switched, a current flows in the armature 1a in the direction of arrow B, the motor 1 is reversely rotated, and the winding drum is wound. Driven down.

The winding drum is driven in the lowering direction,
At this time, if the load is large, the gravitational force acting on the load is added to the driving force of the motor 1, so that the armature 1a is subjected to a rotational force equal to or greater than the steady rotation, and the regenerative current is generated by the armature 1a. appear. This regenerative current is battery 2
However, if the regenerative current amount exceeds the allowable current amount in the battery 2, it will not be accepted,
The excess regenerative current is returned as it is. Then, the meter relay 5 provided on the forward rotation side of the armature circuit detects the excessive regenerative current and turns on the switch 5'provided in the short circuit c to provide the short circuit c. The resistor 3 is energized, converted into heat energy by the resistor 3 and consumed to be kept in equilibrium, so that the armature 1a can be kept normal and the operation can be continued.

The control means of the present invention can be adopted when a DC machine is used as a motor of a lifting machine that operates not only in the hoist described above but also in a condition where gravity is applied to the load. .

[0015]

As described above, according to the present invention, a lifting machine that uses a battery as a power source by solving a problem in suspending a load by reasonably processing an excessive regenerative current with a simple structure. Can drive safely.

[Brief description of drawings]

FIG. 1 is a control circuit diagram as a hoisting motor control unit of a lifting machine using a battery as a power source according to the present invention.

[Explanation of symbols]

1 Motor 1a Armature 2 Battery 3 Resistor 5 Meter relay 5'Switch operated by meter relay

Claims (2)

[Claims] 1. A battery acceptance permit of a regenerative current generated during a lowering drive by the motor, between a forward / reverse switching circuit in a circuit for supplying electric power to an armature of a battery-powered motor and the armature. A hoisting motor control means for a battery-powered lifting machine, characterized in that a resistor for processing an excessive regenerative current exceeding the capacity and a detector for the excessive regenerative current for activating the resistor when the excessive regenerative current is detected are provided. . 2. The switch for the excessive regenerative current is provided in series with an armature circuit of the motor, and a circuit for arranging the resistor is a switch which becomes a closed circuit when the detector detects an excessive current. A hoisting motor control means for a hoisting machine using the battery as a power source according to claim 1.