JPH11294428A - Clip nut - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a clip nut to fix a loosening preventive nut, provided at the top part of a nut body with a loosening preventive means, at an U-shaped clip through resistance welding. SOLUTION: A metallic sheet is bent in a flat U-shape and an upper piece part 12 and a lower piece part, positioned opposite to each other, are integrally interconnected through a bent part 14 to form a U-shaped clip 11, and a nut is welded to the upper piece part 12 of the U-shaped clip to constitute a clip nut 10. A nut is a loosening preventive nut 5 provided at the top part of the nut body 6 of a hexagonal or a square nut with a loosening preventive means 7. An annular protrusion 18 having an inside diameter D higher than the size B of the corresponding side of the nut body 6 and lower than a diagonal size C is formed on the outer peripheral part of a bolt insertion hole formed in the upper piece part 12, and each corner part 6a of the seat surface of the nut body 6 is joined with the annular protrusion 18 through resistance welding. In this case, the each corner part 6a of the nut body 6 is sunk in the annular protrusion 18 and joined therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a clip nut which is inserted into an edge of a plate member and is mounted so as to sandwich the plate member so that a nut is held at a predetermined position. The present invention relates to an improvement in a welded clip nut.

[0002]

2. Description of the Related Art A clip nut of this type is disclosed in Japanese Utility Model Publication No. 7-40724. The clip nut, as shown in FIGS. 6 and 7,
Upper piece of a U-shaped clip 1 formed by bending a metal plate into a flat U-shape and opposed upper piece 2 and lower piece 3 are integrally connected by a bent portion 4 2, a locking nut 5 in which a thin plate-like elastic ring 7 is assembled as locking means on the top of the nut body 6 is fixed by arc welding. In the figure, reference numeral 8 denotes a weld. The elastic ring body 7 has a plurality of elastic claws 7a protruding radially inward on an inner peripheral surface thereof. These elastic claws 7a have a uniform circumferential length and a uniform circumferential length. When the nut body 6 is screwed into the bolt, the elastic claw pieces 7a are individually curved by the angle of the screw thread of the bolt, and can be easily screwed. Despite this, the elastic restoring force acts on the thread to provide a reliable locking effect, and the elastic force acts evenly on the thread of the bolt, so that the thread is not damaged It can be reused.

A locking nut 5 having the above-described elastic ring body 7 is disclosed in Japanese Utility Model Publication No. 46-8496, and is disclosed in Japanese Utility Model Publication No. 7-40724. It is a well-known locking nut which has been known for more than a year and is marketed under the trade name "U-nut".

On the other hand, when welding is employed as a means for fixing the nut body 6 to the upper piece 2 of the U-shaped clip 1, a so-called welding nut having a welding projection provided on the seat surface of the nut body 6 is generally used. 2, resistance welding is performed. However, in the case of the locking nut 5 in which the elastic ring 7 is assembled as a locking means on the top of the nut body 6 as described above, it is very difficult to provide welding projections on the bearing surface of the nut body 6 in terms of manufacturing. Therefore, as shown in the drawing, the outer peripheral portion of the nut main body 6 is fixed to the upper piece portion 2 by arc welding at several locations on the outer peripheral portion.

[0005]

However, when the nut is fixed to the U-clip by such arc welding, not only the welding cost is increased but also the workability is poor and the mass productivity is low.

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the above-mentioned conventional products, and the above locking nut is provided by resistance welding without providing welding projections on the bearing surface of the nut body. Provided is a clip nut which can be easily and efficiently fixed to a U-shaped clip.

[0007]

In order to achieve the above object, the present invention relates to a metal plate formed by bending a metal plate into a flat U-shape. A nut having a nut welded to the upper piece of a U-shaped clip integrally connected by a portion, the nut having a hexagonal or square nut body provided with locking means at the top of the nut body. A ring-shaped projection having an inner diameter that is larger than the opposite side dimension of the nut main body and smaller than a diagonal dimension is provided on an outer peripheral portion of the bolt insertion hole provided in the upper piece part, Each corner is joined to the ring-shaped projection by resistance welding. The corner portion of the nut body sinks into the ring-shaped projection by the resistance welding and is joined thereto, and a circumferential direction of the nut body is locked by a recessed step formed in the ring-shaped projection.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a clip nut 10 according to the present invention. The clip nut 1
Reference numeral 0 denotes a configuration of a U-shaped clip 11 formed by bending a metal plate into a flat U-shape, and an upper piece 12 and a lower piece 13 facing each other are integrally connected by a bent portion 14. FIGS. 6 and 7 show a configuration in which a locking nut 5 in which a thin plate-shaped elastic ring body 7 is attached to the top of the nut body 6 as a locking means is attached to the upper piece 12 of the U-shaped clip 11.
5 is the same as the conventional product shown in FIG.
Have different welding structures. Also, lock nut 5
Is a hexagonal nut, and the configuration of the elastic ring body 7 assembled to the nut main body 6 is the same. Therefore, the same reference numerals are given to the drawings, and the detailed description is omitted.

Next, the locking nut 5 according to the present invention will be described.
Will be described. The upper piece 12 and the lower piece 13 of the U-shaped clip 11 are respectively provided with bolt insertion holes 15 and 16 facing each other, but the peripheral portion of the bolt insertion hole 16 of the lower piece 13 is connected to the upper piece 12. The positioning guide portion 17 is formed at the time of use by standing up to the side. On the other hand, on the outer periphery of the upper surface of the bolt insertion hole 15 of the upper piece 12,
A ring-shaped projection 18 having an inner diameter (D) larger than the opposite side dimension of the nut body 6, that is, smaller than the diagonal dimension (C), is provided. The ring-shaped projection 18
Is required to have high dimensional accuracy in order to form a welding projection for resistance welding, which will be described later. However, as shown in the figure, the dimension of the projection projecting from the lower side of the upper piece 12 and projecting upward is regulated by a die or the like. When processing is performed, the angle of the ring-shaped projection 18 is high even if the height of the projection is limited to a low level, and the dimensional accuracy is high.
This is convenient. The positioning guide portion 17 and the ring-shaped protrusion 18 are naturally processed before the bent portion 14 is provided and the U-shaped clip 11 is formed.

FIG. 5 shows a step of welding the locking nut 5 to the upper piece 12 of the U-shaped clip 11 by an electric resistance welding machine, wherein 21 is an upper electrode, 22 is a lower electrode, and 22 is a lower electrode. The side electrode 22 is provided with a positioning pin 23 made of an electric resistance material such as nichrome steel or austenitic steel. First, the bolt insertion hole 15 of the upper piece 12 is fitted to the positioning pin 23 and positioned and supported on the lower electrode 22. Subsequently, when the locking nut 5 is fitted to the positioning pin 23, the nut body 6 is positioned concentrically with the bolt insertion hole 15, and thus with the ring-shaped protrusion 18, and is brought into contact with and supported by the ring-shaped protrusion 18. At this time, only the corner 6a of the seating surface of the nut body 6 contacts the ring-shaped projection 18, and most of the seating surface at the opposite side does not contact the ring-shaped projection 18. Further, the position of the nut main body 6 fitted to the positioning pin 23 may have any degree of freedom of 360 degrees, so that the efficiency of the welding operation can be improved. In this state, when the upper electrode 21 is pressed against the top surface of the nut body 6 and an electric current flows, the six corner portions 6 of the nut body 6 on the bearing surface side are provided.
a is resistance-welded to the ring-shaped projection 18, and the locking nut 5 is fixed to the upper piece 12. At this time, as shown in FIGS. 3 and 4, each corner 6a sinks into the ring-shaped projection 18 and is joined, and the circumferential direction of the corner 6a is formed in the ring-shaped projection 18. Since they are locked at 19, 19, the joining strength is high, and especially the peeling torque is greatly increased. Reference numeral 20 denotes a fusion joint.

In the above embodiment, the nut body 6 of the locking nut 5 is a hexagonal nut, but may be a square nut. In this case, four corners of the nut main body are resistance-welded to the ring-shaped projection 18.

[0012]

As described above, according to the present invention,
The nut body can be fixed to the U-shaped clip by resistance welding without providing a welding projection on the seat surface of the nut body, so that the locking nut with the locking means at the top of the nut body can be easily attached to the U-shaped clip. In addition, clip nuts with locking nuts can be mass-produced inexpensively and efficiently. In addition, since each corner of the nut body sinks into the ring-shaped protrusion and is joined, and the circumferential direction is locked by the recessed step formed in the ring-shaped protrusion,
Particularly, there is an advantage that the peeling torque is large.

[Brief description of the drawings]

FIG. 1 is a plan view of a clip nut according to the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged cross-sectional view showing a joint portion between a nut main body and a ring-shaped protrusion.

FIG. 4 is a sectional view taken along line 4-4 in FIG. 3;

FIG. 5 is a longitudinal sectional view of an essential part for explaining a welding step of the locking nut.

FIG. 6 is a plan view of a conventional clip nut.

FIG. 7 is a front view of the same.

[Explanation of symbols]

 Reference Signs List 5 Locking nut 6 Nut body 6a Corner of nut body 7 Elastic ring body 7a Elastic claw piece 7b Notch section 10 Clip nut 11 U-shaped clip 12 Upper piece 13 Lower piece 14 Bend 15, 16 Bolt insertion hole 17 Positioning guide part 18 Ring-shaped projection 19 Recessed step part 20 Fusion joining part

Claims (2)

[Claims] 1. An upper portion of a U-shaped clip formed by bending a metal plate into a flat U-shape, and opposing upper and lower pieces are integrally connected by a bent portion. A clip nut in which a nut is welded to one side, wherein the nut is a locking nut provided with locking means on a top of a hexagonal or square nut body, and an outer periphery of a bolt insertion hole provided in the upper piece. A ring-shaped projection having an inner diameter larger than the opposite side dimension of the nut main body and smaller than the diagonal dimension is provided on the portion, and each corner of the seat surface of the nut main body is joined to the ring-shaped projection by resistance welding. A clip nut. 2. The method according to claim 1, wherein the corner portion of the nut body sinks into the ring-shaped protrusion by the resistance welding and is joined.
The clip nut according to claim 1, wherein a circumferential direction of the clip nut is locked by a recessed step formed in the ring-shaped projection.