JPH0521302Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a socket for a nut runner having a polygonal fitting hole into which a bolt head or nut is fitted.

(Prior art) Conventionally, when automatically assembling a workpiece set in a setting jig by having it received by an assembly jig attached to a robot or the like, the socket of the nut runner mounted on the assembly jig must be inserted in advance when receiving the workpiece. The bolt is fitted onto the head of a tightening bolt set together with the work in the setting jig, so that the nut runner receives the tightening bolt.

When receiving the bolt, the socket may be misaligned with respect to the bolt set in the setting jig due to the positioning accuracy of the assembly jig. A socket has been proposed in which a tapered guide portion is formed at the mouth of a polygonal fitting hole into which a bolt head is fitted.

(Problem to be solved by the invention) According to the above socket, the misalignment is corrected by inserting the bolt head into the guide part, and when the bolt head and the fitting hole are in phase with each other by rotation of the socket, the bolt is fitted. The bolt head is fitted into the matching hole.

However, if there is nothing to restrict the rotation of the bolt,
When the socket rotates, the bolt rotates together, making it difficult to properly phase the bolt. Therefore, conventional methods have been used to prevent the bolt from rotating by providing a clamping means to grip the shaft of the bolt at the location where the bolt is set on the setting jig. However, in order to reduce costs, it is necessary to omit the clamping means, and when nuts are used as fasteners, it is difficult to hold the nuts without interfering with the sockets, so it is difficult to hold bolts or nuts. It is desirable to be able to fit it into a socket without locking it.

The object of the present invention is to provide a socket for a nut runner that meets such requirements.

(Means for Solving the Problem) In order to achieve the above object, the present invention provides a socket for a nut runner having a polygonal fitting hole into which a bolt head or a nut is fitted. forming a groove perpendicular to the axis of the groove, opening the fitting hole in the bottom surface of the groove so that a pair of opposing hole wall surfaces match groove wall surfaces on both sides of the groove; A sloped surface that slopes outward in the groove width direction toward the axial direction of the socket is formed on the wall surface.

(Operation) The operation of the present invention will be explained with reference to FIG. With the head _a1 of the bolt set in the setting jig etc. and the fitting hole 3 of the socket 2 being misaligned and out of phase as shown in Figure 5a, turn the socket 2 toward the bolt head _a1. When the groove wall surface 4b of the concave groove 4 is moved forward, the inclined surface 4c formed on the groove wall surface 4b of the concave groove 4 first comes into contact with the bolt head _a1 , and the bolt head _a1 is guided by the inclined surface 4c, and the pair of opposing sides of the bolt head a1 are moved forward. It is inserted into the groove 4 along the groove wall surfaces 4b, 4b on both sides, and the phase shift is corrected as shown in FIG. 5b, and the misalignment of the groove 4 in the groove width direction is corrected.

In addition, when rotating the socket 2 and moving it forward,
There is a concern that the bolt may rotate together with the socket 2 with the inclined surface _4c in contact with the bolt head a1, and the bolt head _a1 may not be able to be inserted into the groove 4, but the phase shift may occur. In this case, the bolt head _a1 only contacts the inclined surfaces 4c, 4c of the groove walls 4b, 4b on both sides at two points, and the frictional force acting on the lower surface of the bolt head, which is in surface contact with the setting jig, is is the bolt head
Since the frictional force acting between a ₁ and socket 2 is greater than the frictional force acting between a 1 and socket 2, the bolt does not rotate together with socket 2, and the forward force of socket 2 pushes the bolt head a ₁ through the inclined surface 4c. A force acts to rotate the bolt in a direction that corrects the phase shift, and thus the bolt head _a1 is reliably inserted into the groove 4 without having to stop the bolt from rotating.

However, in this state, since the longitudinal misalignment δ of the groove 4 remains, the bolt head _a1 comes into contact with the bottom surface 4a of the groove 4, preventing the socket 2 from moving further. Socket 2 attempts to revolve while rotating the bolt around the axis 0 _{and 1} of the bolt, which is held in place by the rotation of 2, but socket 2 returns to its original position O due to the elasticity of the nut runner shaft, etc. Because centering force F acts, suppose the axis of socket 2 moves to point 0 ₂ ' on the circumference of radius δ centered on bolt axis O ₁ as shown in Fig. 6 due to revolution. , the socket 2 is pushed toward the bolt axis 0 ₁ by the longitudinal component force F ₁ of the centering force F in the groove 4, and if the frictional force is ignored, the axis of the socket 2 is at the point O on the line 0 ₁ 0 ₂ '. When the socket ₂ is rotated 90 degrees from the state shown in Fig. 5B, the axis of the socket 2 coincides with the axis of the bolt head _A1 , as shown in Fig. 5C. , the bolt head _a1 fits into the fitting hole 3.

(Example) Referring to FIG. 1, 1 is a setting jig for setting bolt a, 2 is a socket connected to a nut runner (not shown), and the socket 2 has an approximately hexagonal shape as shown in FIG. A fitting hole 3 having a shape is formed, and the fitting hole 3 is
The head a1 of the bolt _a1 set in the setting jig ₁ was fitted into the socket 2 to receive the bolt a.

As shown in FIGS. 2 and 3, the socket 2 has a concave groove 4 perpendicular to the axis of the socket 2.
is formed in the bottom surface 4a of the groove 4 so that a pair of hole wall surfaces 3a, 3a facing the fitting hole 3 match groove wall surfaces 4b, 4b on both sides of the groove 4. Furthermore, an inclined surface 4c is formed on each groove wall surface 4b, which is inclined outward in the groove width direction of the groove 4 toward the axial direction forward of the socket 2.

In this embodiment, since the hole wall surface 3a of the fitting hole 3 is formed into a curved surface, the longitudinal center portion of the groove wall surface 4b is formed into the same curved surface as the hole wall surface 3a, and furthermore, the groove wall surface 4b is formed into the same curved surface as the hole wall surface 3a.
A chamfered portion 3b is formed at the opening edge of the fitting hole 3 relative to the bottom surface 4a of the fitting hole 3, as shown in the fourth figure, to facilitate fitting of the bolt head _a1 into the fitting hole 3. A magnet 5 is attached to the socket 2 so that the bolt a can be attracted to the socket 2.

According to the above configuration, by rotating the socket 2 at a slow speed and advancing it toward the head _a1 of the bolt a inserted through the setting jig 1, the inclined surface 4c is first The phase shift is corrected by the guide function of the socket 2, and then the misalignment is corrected by the centripetal action caused by the rotation of the socket 2, and the bolt head _a1 is securely inserted into the fitting hole 3 without stopping the bolt a with a clamping means or the like. Can be fitted.

The present invention can be similarly applied to the case where a nut is centered and set in a setting jig using a pin, and the nut is received by the socket 2.

In addition, when the socket 2 is opened to the nut runner shaft,
Although the socket 2 may be supported floatingly so as to be freely movable in the axial direction and have a centripetal action via a floating mechanism known in Japanese Utility Model Publication No. 60-74963 and Japanese Utility Model Application Publication No. 60-8086, etc. Even if it is immovably connected to the shaft, the pressing force on the bolt a after the bottom of the concave groove 4 comes into contact with the bolt head _a1 is kept small by the air pressure setting of the air cylinder for advancing and retracting the nut runner, and the elasticity of the nut runner shaft is reduced. It is possible to align the socket 2 with the bolt head _a1 by using , and it is not essential to float the socket on the nut runner shaft.

(Effects of the invention) As described above, according to the invention, the phase shift and misalignment between the bolt head or nut and the socket can be corrected, and the fitting hole of the socket can be fixed without using a clamping means to prevent the bolt or nut from rotating. This has the effect of making it possible to reliably fit bolt heads and nuts.

[Brief explanation of the drawing]

Figure 1 is a side view of one example of the proposed socket;
The figure is an end view of the socket seen from the - line in Fig. 1, Fig. 3 is a side view taken along - line in Fig. 2, and Fig. 4 is a side view taken along the - line in Fig. 2.
The figures are a cross-sectional end view taken along the - line in Fig. 2, Fig. 5 a,
b and c are diagrams for explaining the action when fitting the socket into the bolt head, and FIG. 6 is a mechanical analysis diagram for explaining the centripetal action caused by the rotation of the socket. a...Bolt, a ₁ ...Head, 2...Socket,
3... Fitting hole, 3a... Hole wall surface, 4... Concave groove, 4
a...Bottom surface, 4b...Groove wall surface, 4c...Slope surface.

Claims (1)

[Scope of utility model registration request] In a socket for a nut runner having a polygonal fitting hole into which a bolt head or a nut is fitted, a recessed groove perpendicular to the axis of the socket is formed on the distal end surface of the socket, and the fitting hole is formed on the bottom surface of the recessed groove. The matching holes are opened so that a pair of opposing hole wall surfaces match the groove wall surfaces on both sides of the groove, and the groove wall surfaces are inclined outward in the groove width direction toward the axial direction of the socket. A nut runner socket characterized by forming a surface.