JP3227772B2 - Terminal plate for self-up terminal screw - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a terminal plate for screwing a self-up terminal screw provided so that a washer does not fall off a shaft portion of the terminal screw.

[0002]

2. Description of the Related Art A self-up terminal screw has a washer interposed between a screw head and an annular projection provided around a body portion below a neck of the screw to prevent the washer from falling off.
Such a self-up terminal screw is screwed into the screw because it is provided in the processed portion of the terminal plate that has been burred, but the self-up terminal screw is not pinched between the washer and the terminal plate at the time of shipment. Is screwed into the terminal board and shipped.

FIG. 2 is a sectional view showing a state in which the self-up terminal screw is screwed into the terminal plate as described above. FIG.
In the self-up terminal screw 1, a screw head 2, a male screw 4 provided on the shaft portion 3, an annular projection 5 provided around the shaft portion 3 between the male screw 4 and the screw head 2, Screw head 2
And a washer 6 interposed between the annular projection 5 and the annular projection 5. The washer 6 has a plurality of retaining projections 7 for preventing an electric wire or the like inserted between the washer 6 and the terminal plate 10 from coming out.

[0004] The terminal plate 10 is provided with a female screw 11 into which the male screw 4 of the self-up terminal screw 1 is screwed.
The female screw 11 is formed by subjecting the terminal plate 10 to burring and then screwing the cylindrical portion 12 protruding from the terminal plate 10. At this time, since the burring is performed, the chamfer of the screw hole of the screw 11 is substantially perpendicular. Here, at the time of shipment, the male screw 4 of the self-up terminal screw 1 is screwed into the female screw 11 of the terminal plate 10 with a specified torque without clamping anything between the washer 6 and the terminal plate 10. At this time, the annular projection 5 of the body 3 is chamfered with the screw hole of the female screw 11 of the terminal plate 10.
Hits the part . At this time, since the non-threaded portion from the annular projection 5 to the external thread 4 is long, the effective fitting length of the external thread 4 screwed into the internal thread 11 is short, and is about one pitch of the thread.

[0005]

SUMMARY OF THE INVENTION As described above, the terminal board 1
0, the surface of the screw hole on the washer 6 side of the screw 11
The shape of the take is a right angle. Therefore, when the male screw 4 of the self-up terminal screw 1 is screwed into the female screw 11 of the terminal plate 10 and tightened with a specified torque, the annular projection 5 of the self-up terminal screw 1 is formed on the chamfered portion of the screw hole of the female screw 11. > In this case, a screw flap that spins due to the galling of the screw or the collapse of the screw thread occurs, which makes it impossible to tighten when using an electric wire or the like between the washer 6 and the terminal plate 10. There is a problem.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a self-up terminal that does not cause galling or screw burrs when the self-up terminal screw is screwed into a female screw of the terminal plate without pinching anything between the washer and the terminal plate. It is to provide a terminal board for terminal screws.

[0007]

According to the present invention, in order to solve the above-mentioned problem, the screw is inserted into a shaft portion below the neck of the screw head and is prevented from dropping off by an annular projection provided around the shaft portion. In a terminal plate for a self-up terminal screw, a self-up terminal screw provided with a washer is threaded into a processed portion formed by burring the terminal plate and screwed into the screw, the terminal screw is screwed into the female screw, and a screw head and When the washer contacts the terminal board, the shape of the chamfer is adjusted so that the annular projection does not hit the chamfer of the screw hole of the female screw.
It shall be arc- shaped or inclined .

In the above, the arc- shaped or inclined shape of the chamfer of the screw hole of the female screw of the terminal plate is such that the screw hole surface has a depth of 0.3 to 1.0 times the screw pitch from the terminal plate surface. It shall have a shape extending from the location to the terminal board surface.

[0009]

[Function] Inserted into the shaft hole under the neck of the screw head into the screw hole of the internal thread formed by threading the burring-processed part on the terminal plate, and prevented from falling off by the annular projection provided on the shaft part When the self-up terminal screw provided with the washer is screwed into and the screw head comes into contact with the washer and the terminal plate, the shape of the chamfer is formed in an arc shape so that the annular projection does not hit the chamfered portion of the screw hole of the female screw. Or by making it inclined , when the self-up terminal screw is screwed into the female screw of the terminal plate and tightened to the specified torque without inserting anything between the washer and terminal Since it does not hit the chamfered portion of the screw hole of the female screw, no galling or screwing of the screw occurs.

[0010] Since the circular or inclined shape of the chamfer of the screw hole of the female screw is obtained by burring,
Due to this shape, the machined portion to be threaded is extended by the missing corner. Here, the shape of the chamfer of the screw hole of the female screw is formed in an arc shape or an inclined shape, and the shape of the screw hole surface having a depth of 0.3 to 1.0 times the screw pitch from the terminal plate surface is used. The shape extends from the location to the terminal board surface.

Such a shape is formed for the following reason. To the shape of the chamfer of the female screw of the screw holes in an arc or angled shape, when dropped small corners chamfered screw holes were fastened to the terminal board self-up terminal screw without interposing anything when the surface of the annular projection of the female screw threaded hole of the shaft portion
In picking , this leads to galling of the screws and screwing. On the other hand, when the corner of the chamfer of the screw hole is greatly dropped, when the self-up terminal screw is tightened as described above, the annular projection of the shaft does not hit the chamfer of the screw hole of the female screw. Due to the chamfered shape of the screw hole that was greatly dropped by the burring process, the length of the self-up terminal screw must be made longer than necessary because the female thread processing part extends to a position far away from the terminal plate There are inconveniences.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing a state in which a self-up terminal screw is screwed into a female screw of a terminal plate according to an embodiment of the present invention and tightened. In FIG. 1, the same parts as those in the conventional example of FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted. FIG.
Is different from the conventional example in that the female screw 11 is formed by screwing the female screw 11 in the cylindrical portion 12 which is formed by burring the terminal plate 10 to form an arc- shaped chamfer 13, that is, the surface of the screw hole is formed.
The female screw 11 having a circular arc shape 13 is connected to the terminal plate 10.
It is provided in.

Here, the circle of the chamfer of the screw hole of the female screw 11 is shown.
For the above-described reason, the arc shape 13 is formed from the screw head 2, the washer 6 and the terminal plate from the screw hole surface of the female screw 11 having a depth of 0.3 to 1.0 times the screw pitch from the plate surface of the terminal plate 10. 10
When the contact is made, the annular protrusion 5 of the shaft portion 3 does not hit the chamfer of the screw hole of the female screw 11 so as to reach the plate surface of the terminal plate 10.

[0014] Incidentally, the circular arc-shaped 13 chamfered screw hole of the female screw 11 of the terminal plate 10 by burring, as described above
As a result, the cylindrical portion 12 formed by the burring process of the terminal plate 10 is reduced by the missing portion of the corner portion of the chamfer by the arc shape 13.
Is longer than the conventional one, and accordingly, the length of the female screw 11 becomes longer. With such a configuration, when the self-up terminal screw 1 is screwed into the female screw 11 of the terminal plate 10 without pinching anything between the washer 6 and the terminal plate 10 and tightened with a specified torque, the self-up terminal screw 1 becomes a screw. The head 2 comes in contact with the upper surface of the washer 6, and the retaining protrusion 7 on the lower surface of the washer 6 comes into contact with the terminal plate 10 and is fastened to the terminal plate 10. Female thread 1
Do not chamfer 1 screw hole. Therefore, the galling or screw burring of the screw due to the contact between the annular projection 5 and the chamfer of the female screw 11 does not occur.

Further, since the female screw 11 of the terminal plate 10 extends below the conventional one, the effective fitting length between the male screw 4 of the self-up terminal screw 1 and the female screw 11 of the terminal plate 10 is equal to that of the screw thread. The pitch becomes 1.5 pitches or more, and the effective fitting length of the screw becomes longer than before. In the above embodiment, the chamfer of the female screw 11 of the terminal plate 10 is formed in an arc shape, but may be formed in an inclined shape.

As described above, the terminal plate having the M3.5 female screw having the chamfered shape of the screw hole according to the present invention has the M3.
A self-up terminal screw having five external threads was subjected to a tightening test with a tightening torque of 176.4 N-cm or less. As a result, the rate of occurrence of galling or fuzz of the screw was 0/100. The occurrence rate of screw galling and screw fuzz is 3/5
There were zero.

From these results, it is understood that according to the present invention, there is no occurrence of screw galling or screwing, and a clear effect is obtained.

[0018]

As is apparent from the above description, according to the present invention, according to the above-mentioned structure, the self-up terminal screw is tightened to the terminal plate with a specified torque without pinching anything between the washer and the terminal plate. Also, since the female screw of the terminal plate is extended by burring, the effective fitting length between the self-up terminal screw and the female screw of the terminal plate can be made longer than before. There is.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a state in which a self-up terminal screw is screwed into a female screw of a terminal plate according to an embodiment of the present invention and tightened.

FIG. 2 is a sectional view showing a state in which a self-up terminal screw is screwed into a conventional female screw of a terminal plate and tightened.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Self-up terminal screw 2 Screw head 3 Shaft part 4 Male screw 5 Annular protrusion 6 Washer 10 Terminal plate 11 Female screw

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01R 9/18 H01R 4/34 F16B 35/00 F16B 37/26

Claims (2)

(57) [Claims] 1. A self-up terminal screw having a washer that is inserted into a shaft portion below a neck of a screw head and that is prevented from falling off by an annular projection provided around the shaft portion is extended by burring on a terminal plate. Molded cylindrical flange
In the self-up terminal screw terminal board which is screwed into the screw machined female thread part, the terminal screw is screwed into the female screw, the contact time of said annular projection of the screw head and the washer and the terminal plate of the screw hole of the female screw Cylindrical flange base
The chamfer so that it does not hit the chamfer
Is a terminal plate for a self-up terminal screw, which is formed in an inclined shape . 2. The terminal plate according to claim 1, wherein the shape of the circular or inclined chamfer of the screw hole of the female screw of the terminal plate is 0.3 to 1.0 times the screw pitch from the terminal plate surface. A terminal plate for a self-up terminal screw, wherein the terminal plate has a shape extending from a screw hole surface to a terminal plate surface.