JPH0327348B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a nut runner equipped with a torque detection device for detecting the tightening torque of a nut or the like.

<Prior art> A nut runner equipped with a conventional torque detection device has a cylindrical nut runner main body, which has a thin wall portion with a small diameter at the lower end that corresponds to the tightening torque, and is fixed to a fixed portion below the thin wall portion. The nut runner shaft is rotatably supported on the nut runner body via a bearing so as to be rotatable around a vertical axis, and the nut runner body is provided with a reduction mechanism using planetary gears that connects with the nut runner shaft, and the nut runner shaft is driven to rotate through the reduction mechanism. The motor was fixed to the upper part of the nut runner body, and the strain sensor was fixed to the thin part of the nut runner body. Torque detection of nuts, etc. is done by twisting the thin wall part so that the reaction force against the force of the drive motor to tighten the nut rotates the nut runner body via the nut runner shaft, so that it is detected by a strain sensor. I was getting used to it.

In this way, because a thin wall part is provided in a part of the nut runner body so that the tightening torque of nuts, etc. can be detected, the support rigidity of the thin wall part is not sufficient to support the weight of the drive motor, etc. above the thin wall part. ,
There was a problem that the upper part was more prone to wobbling than the thin part.

<Objective of the Invention> The object of the present invention to solve the above-mentioned problems is to enable the detection of the tightening torque of a nut, etc. without providing a thin wall portion for detecting the tightening torque, and to prevent the nut runner from wobbling. The idea is to create a support structure like this.

<Configuration of the Invention> A nut runner equipped with a torque detection device according to the present invention has a nut runner main body rotatably supported by a support member fixed to a fixed part via a plurality of bearings, and a drive motor fixed to the nut runner main body. A nut runner shaft that is rotationally driven is supported on the nut runner body, a flexible member is connected to the nut runner body and the supporting member, and a strain sensor is provided to detect the deflection of the flexible member by the reaction force acting on the nut runner body. be.

<Examples> Examples of the present invention will be described below based on the drawings. In FIG. 1, reference numeral 1 denotes a fixed part, and a cylindrical support member 2 is fixed to this fixed part 1 at its lower end. A cylindrical nut runner main body 3 passes through the support member 2 and is supported only rotatably via a plurality of bearings 4 and 5. Natsu tranner body 3
A nut runner shaft 6 is supported by the nut runner body 3 via a plurality of bearings 7, 8, and 9 so as to be able to rotate only about the same axis as the nut runner body 3, and a drive motor 10 is fixed to the upper part of the nut runner body 3. A gear 12a is formed on a rotating shaft 12 spline-coupled to an output shaft 11 of a drive motor 10.
A plurality of planetary gears 13 that mesh with the nut runner body 3 are pivotally supported by the nut runner shaft 6, and a fixed gear 14 that meshes with the planetary gears 13 is formed on the inner periphery of the nut runner body 3. The rotation of the output shaft 11 causes the planetary gear 13 to revolve around the output shaft 11 while rotating, thereby transmitting the reduced rotational power to the nut runner shaft 6. A shaft member 15 is spline-coupled to the lower end of the nut runner shaft 6 so as to transmit axial motion and rotational power, and a socket 17 into which a nut or the like is fitted is removably fixed at the lower end of the shaft member 15. A pressure spring 16 for pressing the shaft member 15 is built in between the nut runner shaft 6 and the shaft member 15.

Next, the torque detection device will be explained based on FIGS. 1 and 2. A through hole 18 is formed in the radial direction approximately in the middle of the support member 2, and a concave engagement groove 19 is formed on the outer periphery of the nut runner body 3 at a position corresponding to the through hole 18. Further, a cup-shaped cap 22 is provided at a position corresponding to the through hole 18.
is removably attached to the support member 2, one end of a bending member 20 is attached to the bottom of the cap 22, and the other end of the bending member 20 is removably engaged with the engagement groove 19. The bending member 20 is provided in the rotation support radial direction of the nut runner body 3, and strain sensors 23 are fixed to the bending member 20 at the front and back of the rotation direction of the nut runner body 3. In this way, the nut runner body 3 is prevented from rotating by the bending member 20, and when a large rotational force is generated in the nut runner body 3, the support member 2 is configured to bend the bending member 20 very slightly in the direction of rotation of the nut runner body 3.
Relative rotation occurs between the nut runner body 3 and the nut runner body 3, and the strain sensor 23 detects the tightening torque of the nut or the like. When the cap 22 is removed, the other end of the bending member 20 is disengaged from the engagement groove 19 of the support member 2, and the bending member 20 is replaced together with the cap 22, and the other end of the bending member 20 is engaged with the engagement groove 19. By attaching the cap 22 to the support member 2 in this manner, the magnitude of the tightening torque and the sensitivity of the tightening torque can be easily changed.

Based on the above-described configuration, the tightening operation of nuts and the like and the detection operation of the tightening torque will be explained. The rotation of the output shaft 11 causes the planetary gear 13 to revolve through the rotating shaft 12 while meshing with the fixed gear 14, and the socket 17 rotates through the nut runner shaft 6 and the shaft moving member 15, and the nut fitted in the socket 17 is rotated. etc. are tightened. The reaction force against the force of the drive motor 10 to rotate the socket 17 is
Shaft moving member 15, nut runner shaft 6, planetary gear 13
is transmitted to the nut runner body 3 via the nut runner body 3, and the nut runner body 3 rotates with respect to the support member 2 so as to bend the bending member 20. By bending the bending member 20, the tightening torque of a nut or the like is detected by the strain sensor 23, and when the torque reaches a set value, the drive motor 10 is stopped.

As described above, since the tightening torque of a nut or the like is detected by slightly bending the bending member, there is virtually no relative rotation between the support member and the nut runner body. For this reason,
The above-mentioned torque detection device can also be used in an offset type nut runner in which a nut runner shaft, to which a socket is fixed, is eccentric from the axis of the nut runner body so that a plurality of nut runners do not interfere with each other.

<Effects of the Invention> As described above, the present invention has a structure in which the nut runner main body is rotatably supported by the support member by at least two bearings.
There is no fear that the nut tranner body will wobble. Also,
An engagement groove is formed on the outer periphery of the nut runner body between the two bear rigs, a cup-shaped cap is removably attached to the support member at a position corresponding to the engagement groove, and one end of the cap is attached to the bottom of the cap in the engagement groove. Since the structure is such that the other end of the bending member that is releasably engaged is attached and the strain sensor is attached to the bending member, the bending member cannot be disengaged from the engagement groove of the support member even when the cap is removed from the support member. The bending member can be easily replaced with the cap by holding the cap by attaching the cap to the support member so that one end of the bending member engages with the engagement groove. As a result, it is possible to easily change the magnitude of the tightening torque and the sensitivity of the tightening torque.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is an overall cross-sectional view of a nut runner, and FIG. 2 is a cross-sectional view taken along the - line in FIG. 1. 2...Supporting member, 3...Natsutrunner body,
4, 5...bearing, 6...nut runner shaft,
10... Drive motor, 20... Bending member, 22...
...Cap, 23...Strain sensor.

Claims (1)

[Claims] 1. A cylindrical support member fixed to a fixed part, a nut runner body that penetrates the inside of this support member and is rotatably supported by the support member by at least two bearings, and a drive motor fixed to the nut runner body. a nut runner shaft rotatably supported on the nut runner body and rotationally driven by the drive motor; a socket provided at one end of the nut runner shaft and rotatably engageable with a nut, etc.; and a socket between the two bearings. A concave engagement groove formed on the outer periphery of the nut runner body, a cup-shaped cap that is removably attached to the support member at a position corresponding to the engagement groove, and one end attached to the bottom of the cap and the other end. A bending member provided in the rotation support radial direction of the nut runner main body so as to removably engage with the engagement groove, and a strain sensor attached to the side surface of the bending member to detect bending of the bending member. A nut runner equipped with a detection device.