Duty ratio control device, electric power tool and recording medium
AssigneeMakita Corporation
InventorTakuya Kusakawa
Life of this patent
Estimating the term…
Abstract
A duty ratio control device includes a duty ratio calculation unit and a parameter setting unit. The duty ratio calculation unit, when an acceleration manipulation is performed, calculates a control duty ratio per predetermined timing based on a value of at least one parameter so that a rotation speed of a motor mounted on an electric power tool reaches a target rotation speed corresponding to the acceleration manipulation. The control duty ratio is calculated to be larger as the value of the at least one parameter is larger. The parameter setting unit sets the value of the at least one parameter. The value of the at least one parameter set for a reacceleration manipulation is larger than the value of the at least one parameter set for an initial acceleration manipulation.
Claims15
A duty ratio control device that controls a control duty ratio that determines a magnitude of voltage to be applied to a motor mounted on an electric power tool, the duty ratio control device comprising:
- a duty ratio calculation unit that, when an acceleration manipulation for accelerating a rotation speed of the motor is performed, calculates the control duty ratio per predetermined timing based on a value of at least one parameter so that the rotation speed of the motor reaches a target rotation speed corresponding to the acceleration manipulation, wherein the control duty ratio is calculated to be larger as the value of the at least one parameter is larger;
- and
- a parameter setting unit that sets the value of the at least one parameter, wherein the value of the at least one parameter set for a reacceleration manipulation is larger than the value of the at least one parameter set for an initial acceleration manipulation, the reacceleration manipulation being the acceleration manipulation performed again during a deceleration period in which the motor is being decelerated by a stopping manipulation that stops rotation of the motor, and the initial acceleration manipulation being the acceleration manipulation performed when the rotation of the motor is being stopped.
An electric power tool comprising:
- a motor that receives electric power to rotate;
- a manipulation unit that is provided for a user of the electric power tool to perform an acceleration manipulation for increasing a rotation speed of the motor and a stopping manipulation for stopping rotation of the motor;
- a duty ratio calculation unit that, when the acceleration manipulation is performed, calculates a control duty ratio which determines a magnitude of voltage to be applied to the motor per predetermined timing, based on a value of at least one parameter, so that rotation speed of the motor reaches a target rotation speed corresponding to the acceleration manipulation, wherein the control duty ratio is calculated to be larger, as the value of the at least one parameter is larger;
- a parameter setting unit that sets the value of the at least one parameter, wherein the value of the at least one parameter set for a reacceleration manipulation is larger than the value of the at least one parameter set for an initial acceleration manipulation, the reacceleration manipulation being the acceleration manipulation performed again during a deceleration period in which the motor is being decelerated by the stopping manipulation, and the initial acceleration manipulation being the acceleration manipulation performed when the rotation of the motor is being stopped;
- and
- a drive unit that applies to the motor the voltage determined by the control duty ratio calculated by the duty ratio calculation unit to rotationally drive the motor.
A non-transitory recording medium readable on a computer mounted on an electric power tool including a motor, wherein the recording medium recording a program that makes the computer execute:
- a duty ratio calculation step in which, when an acceleration manipulation for increasing a rotation speed of the motor is performed, a control duty ratio which determines a magnitude of voltage applied to the motor is calculated per predetermined timing based on a value of at least one parameter so that the rotation speed of the motor reaches a target rotation speed corresponding to the acceleration manipulation, and the control duty ratio is calculated to be larger, as the value of the at least one parameter is larger;
- and
- a parameter setting step in which the value of the at least one parameter is set, and the value of the at least one parameter set for a reacceleration manipulation is larger than the value of the at least one parameter set for an initial acceleration manipulation, the reacceleration manipulation being the acceleration manipulation performed again during a deceleration period in which the motor is being decelerated by a stopping manipulation that stops rotation of the motor, and the initial acceleration manipulation being the acceleration manipulation performed when the rotation of the motor is being stopped.
Dependencies are inferred from the claim text.