Torque control device for electrical tools
AssigneeTechway Industrial Co., Ltd.
InventorFu-Hsiang Chung
Life of this patent
Estimating the term…
Abstract
A torque control device for an electrical tool has a switching circuit, a voltage detecting circuit, a torque detecting circuit and a processor. The switching circuit connects between a motor of the electrical tool and a DC voltage source. The voltage detecting circuit detects voltage or current variation of the motor. The torque detecting circuit based on the detected voltage or current variation data outputs an actual torque value of the motor. The processor compares the actual torque value with a default value to determine whether actual torque is greater than the default. If so, the switching circuit is turned off by the processor to prevent the motor from being damaged.
Claims12
A torque control device for an electrical tool having a motor powered by a DC voltage source, the torque control device comprising:
- a switching circuit being connected between the motor and the DC voltage source;
- a processor with an output terminal being connected to the switching circuit to turn on or turn off the switching circuit;
- a voltage detecting circuit having an input terminal being connected between the motor and the DC voltage source to detect voltage variation data of the motor;
- a torque detecting circuit being connected between the voltage detecting circuit and the processor to produce a motor torque value to be output to the processor based on the voltage variation data;
- a torque setting unit being connected to the processor to provide a default torque value to the processor;
- a high voltage protecting circuit being connected between the voltage detecting circuit and the processor and comprising an operating amplifier having
- two input terminals being connected respectively to the voltage detecting circuit and a high reference voltage;
- and
- an output terminal being connected to the processor;
- a low voltage protecting circuit being connected between the voltage detecting circuit and the processor and comprising an operating amplifier having
- two input terminals being connected respectively to the voltage detecting circuit and a low reference voltage;
- and
- an output terminal being connected to the processor;
- and
- a display being connected to the processor to show the default torque.
A torque control device for an electrical tool having a motor powered by a DC voltage source, the torque control device comprising:
- a processor;
- a switching circuit being connected between the motor and the DC voltage source and comprising
- a driving transistor having a base connected to the processor through a resistor, a collector and an emitter;
- and
- a switching transistor having a gate connected to the collector, and a source and a drain connected respectively to the motor and the DC voltage source;
- the processor with an output terminal being connected to the switching circuit to turn on or turn off the switching circuit;
- a high voltage protecting circuit being connected between the voltage detecting circuit and the processor;
- a voltage detecting circuit having a voltage dividing circuit formed by a first resistor and a second resistor connected in series, wherein
- a first terminal of the first resistor is connected to the DC voltage source and the switching circuit;
- and
- a second terminal of the first resistor connecting to the second resistor is connected to the high voltage protecting circuit;
- a torque detecting circuit being connected between the voltage detecting circuit and the processor to produce a motor torque value to be output to the processor based on the voltage variation data;
- and
- a torque setting unit being connected to the processor to provide a default torque value to the processor and comprising a first RC circuit and a first operating amplifier as a buffer.
Dependencies are inferred from the claim text.