JPH05240232A - Cage body structure - Google Patents

Abstract

PURPOSE:To eliminate the breakage of a cover caused by the excessive fastening of a mounting screw and provide a cage body structure capable of facilitating the cover fixation by pressing the cover by a compression spring force. CONSTITUTION:A mounting screw 4 is driven through the through hole 7 of a cover 3 into a base 2, and between the head part 4a of the mounting screw 4 in this driven state and the fastening surface 8a of the cover 3, a compression spring 10 is inserted in the further compressible state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a casing structure used for a casing of a circuit breaker, for example.

[0002]

2. Description of the Related Art A conventional housing structure will be described with reference to FIGS. In the figure, 1 is a housing of a drawer type circuit breaker, 2 is a base, 3 is a cover, 4 is a mounting screw, 5 is a hole 6 in the base 2.
A nut fixed by being embedded therein, 7 is a through hole formed in the cover 3, 8 is a counterbore portion provided in the cover 3, and 9 is a spring washer. The cover 3 is fixed to the base 2 by passing the mounting screw 4 through the counterbore 8 into the through hole 7 and tightening the nut 5 as it is.

[0003]

Since the conventional housing structure is constructed as described above, the mounting screw 4 is not tightened enough for the cover 3 made of a relatively soft material such as electrically insulating synthetic resin. It is performed smoothly without resistance.
Therefore, there is a problem that the cover 3 may be damaged by over-tightening the mounting screw 4, and the fixing of the cover 4 lacks stability because it is difficult to properly tighten the mounting screw 4.

The present invention has been made in order to solve the above problems, and has a housing structure in which the cover is pressed by a compression spring force so as to prevent the cover from being damaged by overtightening the mounting screw and to easily fix the cover. The purpose is to get.

[0005]

According to another aspect of the present invention, there is provided a housing structure in which a mounting screw is screwed into a base through a through hole of a cover, and a head of the mounting screw and a tightening surface of the cover in the screwed state. A compression spring is inserted between and in such a manner that it can be further compressed.

[0006]

In the present invention, since the cover is pressed against the base by the compression spring force, the cover will not be damaged by overtightening the mounting screw.

[0007]

EXAMPLES Example 1. An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a cross-sectional view of the vicinity of a mounting screw, and FIG. 2 is a perspective view showing the nut of FIG. In the figure, 10 is a compression coil spring inserted between the head 4 a of the mounting screw 4 and the tightening surface 8 a of the counterbore 8, and 11 is a pin spanning both holes 5 a of the nut 5.

As shown in FIG. 1, when the mounting screw 4 is screwed into the nut 5 and is in contact with the pin 11, the length of the mounting screw 4 is determined so that the compression coil spring 10 can be further compressed. deep.

When the mounting screw 4 is passed through the through hole 7 of the cover 3 and screwed into the nut 5, the mounting screw 4 stops by hitting the pin 11, so that the mounting screw 4 is not overtightened and the mounting screw 4 is removed. The fixing work by can be done easily. Then, as shown in FIG. 1, when the cover 3 is fixed to the base 2 by the mounting screw 4, the cover 3 is pressed against the base 2 by the compressive bending force of the compression coil spring 10, so that excessive stress is applied by the mounting screw 4. Never.

Embodiment 2. As shown in FIGS. 3 and 4, when a plastic washer 12 is fitted onto the mounting screw 4, the compression coil spring 10 acts on the tightening surface 8a via this plastic washer 12, so that when the mounting screw 4 is tightened, The tightening surface 8a is not scraped by the end portion of the compression coil spring 10 that rotates in the direction.

Also, the protrusion 12a of the plastic washer 12
When the mounting screw 4 is stopped at the desired position by means of, the compression coil spring 10 does not drop off from the mounting screw 4 when the mounting screw 4 is removed from the cover 3, so workability is good.

[0012]

As described above, according to the present invention, since the cover is pressed by the compression spring force, the cover is not damaged by overtightening the mounting screw, and the work of fixing the cover can be easily performed. can get.

[Brief description of drawings]

FIG. 1 is a sectional view around a mounting screw showing a first embodiment of the present invention.

FIG. 2 is a perspective view showing the nut of FIG.

FIG. 3 is a sectional view of the vicinity of a mounting screw showing a second embodiment of the present invention.

FIG. 4 is a plan view showing the plastic washer of FIG.

FIG. 5 is a perspective view showing a conventional one.

6 is a cross-sectional view showing the vicinity of the mounting screw of FIG.

[Explanation of symbols]

 1 Housing 2 Base 3 Cover 4 Mounting Screw 4a Mounting Screw Head 5 Nut 7 Through Hole 8a Tightening Surface 10 Compression Spring 12 Plastic Washer

Claims (2)

[Claims] 1. A housing structure comprising a base and a cover and fixing the both with a mounting screw, wherein the mounting screw is screwed into the base through a through hole of the cover, and the mounting is performed in this screwed state. A housing structure, wherein a compression spring is inserted between the head of the screw and the tightening surface of the cover in a more compressible state. 2. A plastic washer is fitted to the mounting screw to hold the compression spring near the head of the mounting screw, and the compression spring acts on the tightening surface of the cover through the plastic washer. The casing structure according to claim 1.