JPH019095Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a tangent piece that attaches an earth bond wire to a conduit or makes branch connections of electric wires strong and reliable, and is easy to attach and manufacture.

In Japanese Utility Model Publication No. 42-15968, one end of a metal plate cut into a rectangular or other shape is bent outward into an L shape, and an outwardly bulging arcuate surface is formed on this bent piece. and the other end of the metal plate is bent inward into a hook shape or a V shape to form a locking part, and the lengths of the locking piece and the locking part are approximately equal, and this metal plate Wrap it around a connecting member such as a conduit or wire, apply the locking piece at one end to the outer surface of the connecting member, extend the other end linearly in the direction of connection of the connecting member, and lock the locking part. It is a tangential piece that is secured to a piece to form three layers, and the three-layer portion is sandwiched between articulators, bent in the direction of bending of the locking piece, and crimped to the outer surface of the connecting member. In this tangent piece, the tip of the locking part is a sharp edge that remains separated from the strip material, so
When this locking portion is placed on the arcuate surface of the locking piece and the tip of the locking portion is overlapped with the bent portion of the base of the arcuate surface and bent, the sharp tip of the locking portion comes into pressure contact with the bent portion of the base of the arcuate surface. Does not cause slippage. Therefore, the tension applied between the locking piece and the tangent piece causes the tangent piece to exceed its elastic limit,
The base contact portion may crack and break. This phenomenon mainly occurs during work at high places such as utility poles, and therefore poses many problems in maintenance management.

In addition, in Japanese Utility Model Publication No. 56-27669, a reinforced upright part is provided by protruding several ribs formed at a wider angle than a right angle at the tip of the upper side of the tightening occlusal part. A nearly semicircular gap is always formed in which the upper and lower edges of the upright piece are in contact with each other. Therefore, even if the upper side of the occlusal part and the lower side of the occlusal part are brought into occlusion and pushed down, no clamping force is generated on the clamp. That is, as the occlusal part is tilted down, the lower side of the occlusal part protrudes along the upper and lower edges of the upright part and bulges like a mountain, which has the drawback that no tightening force is generated.

This invention eliminates the above-mentioned drawbacks, and makes a locking part by bending one end of the metal plate inward in a hook or V shape, and then folding the tip inward or outward to form a double layer. When the tip is viewed from the side, a locking portion having a thick circular arc surface is formed on the end surface, and this locking portion is hooked onto a locking piece at the other end of the metal plate, and the locking piece is bent in the bending direction. It is folded back together with the locking part to form a four-layer bent part,
The arcuate surface of the locking piece is deformed into a straight line to increase its effective length, and the radius of rotation of the locking piece at one end of the metal plate is extended outside the radius of rotation of the locking part. Even if compressive force is applied to the metal plate by tightening it tightly around the connecting member, it will not bend during tightening work and become impossible to tighten, and the locking piece is folded back around the arcuate surface of the tip of the locking part and surrounded on the outer circumferential surface of the pipe. The purpose of this invention is to prevent breakage at the bent portion of the locking piece by keeping the tension of the metal plate at an appropriate level by letting the locking piece slide around the outer circumferential surface of the arcuate surface of the locking part. That is.

Other objects, configurations, functions, and effects of this invention will be explained with reference to the drawings.

1 is a metal plate made of a copper plate or the like cut into a rectangular shape and having a required length. One end of this metal plate 1 is
A locking piece 2 is formed by bending it into a shape to form a locking piece 2 having an arcuate surface 2a, and a groove 5 for fitting the earth bond wires 3 and 4 is formed in the lateral direction of the metal plate 1 on the inside of this locking piece 2. An unevenness 6 is formed in the longitudinal direction of the metal plate 1 in the joint groove 5, and curved surfaces 8 and 9 are formed on both sides of the groove 5 so as to follow the outer circumferential curved surface of the conduit 7. A locking portion 11 is formed by bending the other end of the locking portion 11 inward from the folded edge 11a and bending it into a hook shape to approximately the same length as the L-shaped bent locking piece 2. Double layer part 13a is folded inward (or outward) in a U-shape.
The folded end portion is formed into an arcuate surface 13 when viewed from the side, and an inwardly pointed protrusion (or a vertically split conical protrusion) is formed on the inner surface of the metal plate 1.

To tighten the bond wires 3 and 4 to the conduit 7, first, as shown in FIG. 1 with the fitting groove 5 on the inside, and connect the earth bond wire 3 to the fitting groove 5.
4 and briar 14 as shown in Fig. 3.
The metal plate 1 and the locking part 11 are sandwiched between the metal plate 1 and the locking part 11.
is engaged with the locking piece 2. Then, the arcuate surface 13 is positioned outside the arcuate surface 2a of the locking piece 2, and the double layer portion 13
A is clamped between the curved surface 9 of the metal plate 1 and the locking piece 2. Therefore, the arcuate surface 2a of the locking piece 2 has four layers, and this four layer portion is clamped and tightened with the briers 14. The direction in which this briar gripping part is bent is to bend it to the left to form a curved surface 9 as shown in Figure 4.
, and further press and crush the circular arc surface 13 as the center. Therefore, the band 1 is tightly wound around the outer peripheral surface of the conduit 7, and the bond wires 3, 4 are tightly attached to the conduit. Further, since the arcuate surface 2a of the metal plate 1 is bent by the arcuate surface 13 of the locking portion 11 with a radius at least larger than the radius of the arcuate surface 13, the arcuate surface 2a is bent by the arcuate surface 13 of the locking portion 11.
3 and does not cause permanent strain on the circular arc surface 2a, no cracks are generated near the circular arc surface 2a due to permanent strain, and no breakage occurs. In addition, when the locking piece 2 is bent with a briar, the conduit 7 and the bond wires 3, 4 will be connected to each other.
The oxide film, thin enamel paint, etc. between the metal plate 1, the electric conduit 7, and the bond wires 3 and 4 are destroyed, and these members are cold-welded to each other with their base surfaces exposed. If the coating is strong such as polyethylene, as the inward sharp protrusions 12, 12 formed on the metal plate 1 are tightened to the conduit, the inward sharp protrusions 12, 12 will bite into the coating. is destroyed, and the electric conduit 7 and the metal plate 1 come into contact with each other.

In the tightening part of the metal plate 1, the arcuate surface 2a has four layers, and the folded edge 11a has three layers, overlapping each other, so once it is bent as shown in Figure 4, it will not return to its original shape. The arcuate surface 13 prevents the arcuate surface 2a in this portion from bending, and the reaction force of the compressive force causes the metal plate portion wrapped around the conduit 7 to extend, thereby tightly tightening the conduit.

By configuring this idea as described above,
Locking part 11 when wrapping a metal plate around a conduit and tightening it
The apex of the arcuate surface 13 formed by folding back the tip of the locking piece 2 abuts and matches the inner surface of the arcuate surface 2a of the locking piece 2,
The tip of the locking piece 2 hits the inner surface of the fold line 11a of the locking part 11, and when the two matching pieces are overlapped and gripped with pliers, the fold line 11a is firmly squeezed to make the bending angle acute and pushed down. The locking piece 2 and the locking part 11 share the compressive force, and even in the face of a strong compressive force, the locking piece 2 and the locking part 11 can exert a strong tightening force without bending. In addition, even if an external force is applied to the protruding part called the raised part, the tangential piece will loosen because the locking piece 2, the locking part 11, and the locking piece 2 overlap and there is no gap between them. Since the arcuate surface can be formed at the same time when cutting a metal plate from a long metal strip, it is easy to manufacture and can be provided at a relatively low cost.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention. Figure 1 is a perspective view of the unfolded tangent piece, and Figures 2, 3, and 4 show how the tangent piece is wrapped around the conduit and the bond wire is tightened. FIG. DESCRIPTION OF SYMBOLS 1... Metal plate, 2... Locking piece, 3, 4... Bond wire, 5... Fitting groove, 6... Unevenness, 7... Electric conduit, 10... Straight part of metal plate, 11 ... Locking portion, 11a... Broken line, 12, 12... Inward sharp protrusion, 13... Arc surface of locking portion, 13a... Double layer portion.

Claims (1)

[Scope of utility model registration request] One end of a strip-shaped metal plate 1 is bent inward into a hook shape or a V shape, and the tip is further folded back inward to form a double layer part 13a, and the folded end forms an arcuate surface 13 when viewed from the side. The formed locking part 11
The other end of the metal plate 1 is bent outward into an L shape to form a locking piece 2 having an outwardly bulging arcuate surface 2a, and the length of the locking portion 11 and the locking piece 2 is The metal plate 1 is wound around a connecting member 7 such as a conduit or an electric wire, the locking piece 2 is applied to the outer surface of the connecting member 7, and the other end is tied in a straight line in the direction of the tangent to the connecting member 7. The locking portion 11 is locked to the locking piece 2 to form a bent four-layer overlapping portion.
The layer overlapping portion is held between the articulators, and the bent circular arc surface 2a of the locking piece 2 is bent in the bending direction along the circular arc surface 13 of the locking portion 11, so that it is pressed against the outer surface of the bent connecting member 7. tangent piece.