JPH0253198B2 - - 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 part with a small diameter formed at the lower end in accordance with the tightening torque, and is fixed to a fixed part below the thin wall part. A nut runner shaft rotatable around a vertical axis is supported on the nut runner body via a bearing, and a reduction mechanism using planetary gears connected to the nut runner shaft is installed in the nut runner body, 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 for nuts, etc. is performed using strain sensors because the reaction force against the force of the drive motor to tighten the nut acts to rotate the nut runner body and twists the thin walled portion.

The range in which tightening torque can be detected with high precision is limited, and if an attempt is made to detect tightening torque outside the range with high precision, the above configuration requires that the entire inside of the nut runner body be inspected in order to replace the nut runner body. There was a problem that it was troublesome to disassemble and the tightening torque could not be changed.

<Objective of the Invention> An object of the present invention to solve the above-mentioned problems is to provide a nut runner that can easily change the tightening torque and can detect the tightening torque over a wide range with high accuracy.

<Structure of the Invention> A nut runner equipped with a torque detection device according to the present invention includes a cylindrical support member fixed to a fixed part and having a through hole formed in the radial direction, and an inner side of the support member extending perpendicularly to the through hole. A nut runner body is rotatably supported by a support member by at least two bearings that penetrate in the direction of the through hole and are provided on both sides of the through hole, and has an engagement hole formed on the outer periphery at a position corresponding to the through hole; a fixed drive motor; a nut runner shaft that is rotatably supported on the nut runner body and rotationally driven by the drive motor; a socket that is provided at one end of the nut runner shaft and is rotatably engageable with a nut or the like; a cap that is removably attached to the outer surface of the support member at a position corresponding to the through hole; one end is coupled to the cap, and the other end is radially engaged with the engagement hole in a removable and rotational direction; The bending member includes a bending member and a strain sensor attached to the bending member to detect the deflection of the bending member.

<Example> Hereinafter, an example of the present invention will be described 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 via a plurality of bearings 4 so as to be only rotatable. 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. Drive motor 10
A rotating shaft 12 spline-coupled to an output shaft 11 of
A gear 12a is formed in the
A plurality of planetary gears 13 meshing with the nut runner shaft 6
A fixed gear 14 is pivotally supported by the planetary gear 13 and meshes with the planetary gear 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 an engagement hole 19 is formed in the nut runner body 3 at a position corresponding to the through hole 18. The cap 22 to which the bending member 20 is fixed according to the tightening torque is removably fixed to the support member 2 by removably engaging one end of the bending member 20 with the engagement hole 19. Bending member 20
Strain sensors 23 are fixed to the front and rear of the. The bending member 20 is provided in a radial direction with respect to the rotation center of the nut runner body 3. 24 is the strain sensor 2
This is an insertion hole formed in the cap 22 for inserting the wire No. 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 and the nut runner body 3 are moved relative to each other so that the bending member 20 is bent very slightly in the direction of rotation of the nut runner body 3. Rotation occurs, and the strain sensor 23 detects the tightening torque of the nut or the like.

A plurality of caps 22 to which bending members 20 are fixed according to the tightening torque are prepared in advance.
The tightening torque can be easily changed by simply replacing the cap 22.

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.

In the above-described embodiment, the bending member is fixed to the cap with a bolt, but the bending portion may be formed integrally with the cap.

<Effects of the Invention> As described above, in the present invention, the nut runner body is disposed inside the cylindrical support member at least twice.
Since the nut runner body is rotatably supported by two bearings, the support rigidity of the nut runner body is increased, and there is no fear that the nut runner body will wobble. Furthermore, when removing the cap, one end of the bending member can be separated from the engagement hole formed in the nut runner body, making it easy to change the tightening torque just by replacing the cap. . Furthermore, although the support member and two bearings increase the length of the nut runner in the rotational axis direction, the structure is such that a bending member and a strain sensor are provided between the two bearings to detect the tightening reaction force acting on the nut runner body. Therefore, the overall length of the nut runner does not become longer than that of a conventional nut runner in which a flexible member is provided at the lower end of the nut runner body.

[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... Support member, 3... Nut runner body, 4, 5
... Bearing, 6... Nut runner shaft, 10... Drive motor, 19... Engagement hole, 20... Bending member, 22...
Cap, 23...Strain sensor.

Claims (1)

[Claims] 1. A cylindrical support member that is fixed to a fixed part and has a through hole formed in the radial direction, and at least two bearings that penetrate the inside of this support member in a direction orthogonal to the through hole and are provided on both sides of the through hole. a nut runner body rotatably supported by a support member and having an engagement hole formed at a position corresponding to the through hole; a drive motor fixed to the nut runner body; and a drive motor rotatably supported by the nut runner body and the drive A nut runner shaft rotationally driven by a motor, a socket provided at one end of the nut runner shaft and capable of rotationally engaging a nut, etc., and detachably attached to the outer surface of the support member at a position corresponding to the through hole. a cap, a bending member provided in a radial direction such that one end is coupled to the cap and the other end is removably engaged with the engagement hole in the rotational direction; and a bending member attached to the bending member and configured to bend A nut runner equipped with a torque detection device consisting of a strain sensor that detects.