JPH0572376U - Impact wrench device - Google Patents

Abstract

(57) [Summary] [Purpose] Improving the reliability of tightening work using an impact wrench by easily and accurately detecting tightening defects due to nut galling. A rotation for outputting a signal in response to the rotation speed of the output shaft 2 to an output shaft 2 of an impact wrench 1 equipped with a torque detection means for notifying when the tightening torque reaches a predetermined reference torque. Provide a sensor. Further, by providing an informing means 7 for informing the operator whether or not the rotation speed of the output shaft 2 calculated based on the signal output from the rotation sensor exceeds a predetermined reference rotation speed, the tightening torque can be reduced. The propriety of the rotation speed of the output shaft 2 when the reference torque is reached is judged and the result is notified to the operator.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an impact wrench device capable of shock-tightening nuts or bolts using compressed air or the like, and more specifically, it is possible to avoid a tightening failure due to nut galling or the like. It relates to an impact wrench device.

[0002]

[Prior Art]

 In order to stabilize the tightening torque of nuts with an impact wrench in recent years, torque detection means has been provided so that when the tightening torque applied to nuts reaches a predetermined reference torque, the operator will be notified to that effect. There is something. Therefore, in a normal state, it is possible to recognize whether or not the nut has been tightened with an appropriate torque, based on the notification content of the torque detection means.

However, in the case where the properness of the tightened state is judged only by the magnitude of the tightening torque as described above, for example, in the case of nut galling, the nut is not tightened and rotated actually. However, there was a problem that the tightening torque increased and the display (notification) was made as if the tightening was performed normally.

[0004]

[Problems to be solved by the device]

 The present invention has been made in view of such circumstances, and an impact wrench device capable of accurately detecting and notifying (displaying) a tightening failure caused by nut galling or the like is provided. The challenge is to improve the reliability of the tightening work using.

[0005]

[Means for Solving the Problems]

 In order to solve the above problems, the present invention responds to the rotation speed of an output wrench of an impact wrench equipped with a torque detection means for notifying when the tightening torque reaches a predetermined reference torque. A rotation sensor that outputs a signal is provided. Further, the impact trench device is configured by providing a notifying means for notifying the operator whether or not the rotation speed of the output shaft calculated based on the signal output from the rotation sensor exceeds a predetermined reference rotation speed. It is characterized by doing.

[0006]

[Action]

 When tightening the nut using the impact wrench device configured as described above, temporarily tighten the nut with your hand and then tighten the socket of the impact wrench with the nut. When the tightening operation is performed in this manner, the actual rotation speed of the nut is detected. Then, the tightening completion signal is output only when the tightening torque reaches the reference torque and the number of revolutions of the nut (impact wrench output shaft) is greater than the reference number of revolutions. You just have to finish the operation.

However, when the nut galling occurs, the rotation speed of the nut has not reached the reference rotation speed, so that the tightening completion signal is not output even if the tightening torque reaches the reference torque. Therefore, it is possible to easily and accurately detect a tightening failure due to nut galling, etc., and the reliability of tightening work using an impact wrench is improved.

[0008]

【Example】

 An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view of an essential part showing an embodiment of an impact wrench device according to the present invention. A window hole 4 is provided in a casing 3 which covers an output shaft 2 of an impact wrench 1 having a torque detecting means (not shown). It is set up.

Further, by fixing the hexagon nut 5 on the outer peripheral surface of the output shaft 2 and providing the proximity switch 6 with the tip facing the rotating outer peripheral surface of the hexagon nut 5, the rotation speed of the output shaft 2 A rotation sensor that outputs a signal based on By providing the notification means 7 to which the output signal of the proximity switch 6 is supplied, whether the rotation speed of the output shaft 2 calculated based on the output signal of the proximity switch 6 exceeds a predetermined reference rotation speed. The operator is informed of whether or not.

Reference numeral 8 is a display window for displaying the calculated rotation speed numerically, 9 is a display lamp for displaying whether or not the calculated rotation speed exceeds a predetermined reference rotation speed, and 10 is a reference rotation for comparison. A setting knob 11 for setting the number is a stay for mounting the proximity switch 6 so that the position can be adjusted. The stay is fixed to the flange of the impact wrench 1 together, and a socket (not shown) is coupled to the tip of the output shaft 2. ing.

In the impact wrench device configured as described above, when the output shaft 2 is rotationally driven with the start of the impact wrench 1, the hexagon nut 5 is rotated together with the output shaft 2 and the corner portions thereof are The tip of the proximity switch 6 is sequentially passed. Further, since the proximity switch 6 outputs a pulse signal each time the corner of the hexagon nut 5 passes, the notification means 7 is supplied with a signal in response to the rotation speed of the output shaft 2, and based on this signal. Then, the rotation speed of the output shaft 2 is calculated.

Then, the calculated rotation speed at the time when the tightening torque reaches the reference torque and the signal is output from the torque detection means is compared with the reference rotation speed, and the comparison result is displayed on the display lamp 9. The calculated rotation speed at that time is displayed on the display window 8. Therefore, if the display by the display lamp 9 of the notification means 7 is OK, it means that the nut has been normally tightened, and the next nut is tightened. If it is NG, it means that the nut is not properly tightened due to galling. The cause should be eliminated and the tightening operation should be performed again.

The notifying means 7 receives the signal to start (start) the impact wrench 1, resets the memory and display contents of the previous calculated rotation speed, and starts calculation of a new rotation speed to detect torque. The operability of the impact wrench 1 is deteriorated because the calculated rotation speed is displayed when the signal is output from the means, and the calculated rotation speed is compared with the reference rotation speed to display the comparison result. Nor. Further, since the reference rotation speed can be arbitrarily changed with the setting knob, the optimum reference rotation speed can be set according to the tightened nut.

[0014]

[Effect of the device]

 As is clear from the above description, according to the present invention, in addition to the conventional torque detection, the number of rotations is detected to judge whether the tightening state is proper. Can be detected easily and accurately, which increases the reliability of the tightening work by impact lending. Therefore, when the impact-lench device according to the present invention is used in an automobile assembly line, it is possible to reliably prevent problems due to improper tightening of nuts or bolts.

[Brief description of drawings]

FIG. 1 is a perspective view of essential parts showing an embodiment of an impact wrench device according to the present invention.

[Explanation of symbols]

 1 Impact wrench 2 Output shaft 3 Casing 5 Hexagon nut 6 Proximity switch 7 Notification means 8 Display window 9 Indicator lamp

Claims (1)

[Scope of utility model registration request] 1. An impact wrench equipped with a torque detection means for notifying when the tightening torque reaches a predetermined reference torque, and a rotation sensor for outputting a signal in response to the rotational speed of the output shaft of the impact wrench. And an informing unit for informing the operator whether or not the rotation speed of the output shaft calculated based on the signal output from the rotation sensor exceeds a predetermined reference rotation speed.