Power tool
AssigneeNanjing Chervon Industry Co., Ltd.
InventorsWeipeng Chen, Dezhong Yang, Wencheng Li
Life of this patent
Estimating the term…
Abstract
A duty ratio under different working conditions is determined according to an analysis of a characteristic parameter x of a motor of a power tool and then a drive circuit is controlled with the duty ratio to drive the motor to operate. It is only needed to calculate the duty ratio without needing to make any variable to the circuit hardware or the mechanical structure of the power tool. That is, the duty ratio can be adjusted to achieve optimized control of the motor, thereby optimizing the working performance such as an output torque of the power tool.
Claims15
A power tool, comprising:
- a motor, comprising a stator and a rotor;
- a transmission device, configured to connect the rotor to a tool accessory;
- a drive circuit, configured to output a switch signal to drive the rotor of the motor to operate;
- a control unit, configured to output a drive signal to control the drive circuit;
- and
- a power supply device, configured to supply power to the motor, the drive circuit, and the control unit;
- wherein the control unit is configured to determine a variable ΔPWM of a duty ratio according to a variable Δx of a characteristic parameter of the motor, wherein the variable ΔPWM of the duty ratio is obtained by a function f(Δx) and is within a range of 0.01 to 0.1, and according to the variable ΔPWM of the duty ratio, output the drive signal to the drive circuit to control the rotor of the motor to operate to output a driving force.
A power tool, comprising:
- a motor, comprising a stator and a rotor;
- a transmission device, configured to connect the rotor to a tool accessory;
- a drive circuit, configured to output a switch signal to drive the rotor of the motor to operate;
- a control unit, configured to output a drive signal to control the drive circuit;
- and
- a battery pack, configured to supply power to the motor, the drive circuit and the control unit;
- wherein the control unit is configured to determine a variable ΔPWM of a duty ratio according to a variable Δx of a characteristic parameter of the motor, wherein the variable ΔPWM of the duty ratio is obtained by a function f(Δx) and is within a range of 0.1 to 0.2, and to output the drive signal to the drive circuit according to the variable ΔPWM of the duty ratio, to control the rotor of the motor to operate to output a driving force.
A power tool, comprising:
- a brushless motor, comprising a stator and a rotor;
- a transmission device, configured to connect the rotor to a tool accessory;
- a drive circuit, configured to output a switch signal to drive the rotor of the brushless motor to operate;
- a control unit, configured to output a drive signal to control the drive circuit;
- and
- a power supply device, configured to supply power to the brushless motor, the drive circuit, and the control unit;
- wherein the control unit is configured to determine a variable ΔPWM of a duty ratio according to a variable Δx of a characteristic parameter of the brushless motor and a characteristic parameter V of the power supply device, wherein the variable ΔPWM of the duty ratio is obtained by a function f(Δx, V) and is within a range of 0.01 to 0.2, and to output the drive signal to the drive circuit according to the variable ΔPWM of the duty ratio, to control the rotor of the brushless motor to operate to output a driving force.
Dependencies are inferred from the claim text.