JP2005238418A5

JP2005238418A5 -

Info

Publication number: JP2005238418A5
Application number: JP2004054479A
Authority: JP
Filing date: 2004-02-27
Publication date: 2007-04-12
Anticipated expiration: 2024-02-27

Claims

A gripping portion incorporating an electric motor is provided, and a driven shaft for rotationally driving a driver bit is coupled to the output shaft of the electric motor via a speed reduction mechanism including a planetary gear, and the cylindrical casing surrounding the speed reduction mechanism is An internal gear that meshes with the planetary gear of the speed reduction mechanism is rotatably disposed, and between the clutch surface formed on the closed bottom surface portion of the internal gear and the circular bottom surface portion of the gripping portion side cylindrical casing facing the clutch surface. In an electric driver with a clutch mechanism using steel balls ,
One end of the torsion bar is coupled to a part of the outer periphery of the internal gear of the speed reduction mechanism, and the other end is led out to the outside of the gripping part through an opening provided in the gripping part side cylindrical casing, and outside the gripping part. And extending in parallel to the axial direction and fixedly arranged on the gripping portion, and a strain gauge is stretched on the stress displacement portion of the torsion bar, and a torque value is detected based on a detection signal of the strain gauge. An electric screwdriver having a torque detecting function, characterized in that the screw tightening torque value detecting means is provided.

A gripping portion incorporating an electric motor is provided, and a driven shaft for rotationally driving a driver bit is coupled to the output shaft of the electric motor via a speed reduction mechanism including a planetary gear, and the cylindrical casing surrounding the speed reduction mechanism is An internal gear that meshes with the planetary gear of the speed reduction mechanism is rotatably disposed, and between the clutch surface formed on the closed bottom surface portion of the internal gear and the circular bottom surface portion of the gripping portion side cylindrical casing facing the clutch surface. A clutch mechanism using a steel ball is provided, one end of the torsion bar is coupled to a part of the outer periphery of the internal gear of the speed reduction mechanism, and the other end is connected to the grip part via an opening provided in the cylindrical casing of the grip part. In addition to extending to the outside, it extends parallel to the axial direction outside the gripping part and is fixedly placed on the gripping part, and a strain gauge is stretched on the stress displacement part of the torsion bar. Use a power screwdriver with a torque detecting function provided with a screw tightening torque value detecting means arranged to detect the torque value based on the detection signal of the strain gage,
A screw tightening torque value storage means for storing and holding the screw tightening torque value of the electric screwdriver at the time of completion of screw tightening of each screw by repeatedly performing screw mounting on the required screw mounting target object by the electric screw driver a plurality of times. And
The maximum torque value and the minimum torque value are extracted from a plurality of screw tightening torque values stored and held in the screw tightening torque value storage means, and the deviation between the maximum torque value and the minimum torque value and the set torque value is obtained. And an allowable value calculating means for calculating an upper limit value and a lower limit value, respectively, in addition to the maximum torque value and the minimum torque value corresponding to about 5 to 10% ,
An upper limit value and a lower limit value calculated by the allowable value calculation means are set for the screw tightening torque value detection means of the electric driver as allowable values for the set torque value of the electric driver. Torque management system using an electric screwdriver .

A constant voltage circuit with a built-in electric motor, a driven shaft that rotationally drives a driver bit to the output shaft of this electric motor, and a load resistance that detects the load current of the electric motor in the drive power line of the electric motor. Are connected to each other, the potential difference caused by the load current flowing through the load resistor is compared with a predetermined constant voltage set by the constant voltage circuit, and the load current is changed to an overload current greater than a predetermined value to set the potential difference. When a constant voltage is exceeded and the overload current continues to flow for a certain period of time, the drive power line of the electric motor is cut off, and the constant voltage set by the constant voltage circuit is set to the screw tightening torque of the electric driver. The voltage difference corresponding to the value is set, and the potential difference caused by the load current flowing through the load resistance that detects the load current of the electric motor Use a power screwdriver with a torque detecting function provided with a screw tightening torque value detection means configured to detect and,
A screw tightening torque value storage means for storing and holding the screw tightening torque value of the electric screwdriver at the time of completion of screw tightening of each screw by repeatedly performing screw mounting on the required screw mounting target object by the electric screw driver a plurality of times. When,
The maximum torque value and the minimum torque value are extracted from a plurality of screw tightening torque values stored and held in the screw tightening torque value storage means, and the deviation between the maximum torque value and the minimum torque value and the set torque value is obtained. And an allowable value calculating means for calculating an upper limit value and a lower limit value, respectively, in addition to the maximum torque value and the minimum torque value corresponding to about 5 to 10%,
An upper limit value and a lower limit value calculated by the allowable value calculation means are set for the screw tightening torque value detection means of the electric driver as allowable values for the set torque value of the electric driver. Torque management system using an electric screwdriver.