JPH0755038Y2 - Electromagnetic shield box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an electromagnetic shield box in which an electronic circuit device such as a control device or an alarm device is placed.

[Conventional technology]

Conventionally, this type of electromagnetic shield box has a structure in which a lid is simply fitted to the box body, and a gap may occur between the box body and the lid.

[Problems to be solved by the device]

Therefore, an external electromagnetic wave may enter the box through the gap and adversely affect the electronic circuit device mounted in the box.

Therefore, an object of the present invention is to provide an electromagnetic shield box that does not allow external electromagnetic waves to enter.

[Means for Solving the Problems]

The electromagnetic shield box of the present invention comprises a box body having an opening on the front surface, a lid arranged on the front surface of the box body, one piece fixed to the back surface of the lid, and the other piece on the opening edge of the box body. The reinforcing metal fitting having an L-shaped cross section located inside, and the abutting portion, which is fixed to the back surface of the lid together with one piece of the reinforcing metal fitting, is bent so as to be convex to the outside of the other piece of the reinforcing metal fitting. A shield metal fitting extending from the fixed portion is provided, both ends of the contact portion are supported by both end portions of the other piece of the reinforcing metal fitting, and one end portion in the extending direction of the contact portion is bent. The abutting portion is pressed against the inner peripheral surface of the opening edge portion while holding one end of the other piece of the reinforcing metal fitting.

[Action]

According to the configuration of this invention, the abutting portion of the shield metal member is bent so as to be convex to the outside of the other piece of the reinforcing metal member, and the abutting portion is elastically elastically attached to the inner circumference of the opening edge of the box body. Since the structure is pressed against the surface, external electromagnetic waves do not enter the box. In this case, since the contact portion is inserted into the inner peripheral surface of the opening edge portion, the lid can be mounted without rattling without being affected by the member pressing the lid toward the box body side. Further, since both ends of the contact portion are supported by both ends of the other piece of the reinforcing metal fitting, it is possible to suppress the inward bending of the contact portion due to the reaction force received from the opening edge portion of the box body. For this reason, the contact portion has high adhesion even after long-term use, and external electromagnetic waves can be further blocked. Furthermore, since one end of the contact part in the extension direction is bent and the other end of the reinforcing metal fitting is held, the contact part does not bend outward due to external force, etc. to go into.

〔Example〕

An electromagnetic shield box according to an embodiment of the present invention will be described with reference to FIGS. 1 to 10.

This electromagnetic shield box has a box body 1 having an opening on the front surface and housing an electronic circuit device, and a lid 2 arranged on the front surface of the box body 1 to cover the box body 1.
Reinforcing metal fitting 7 having an L-shaped section, one piece fixed to the back surface of the lid 2 and the other piece positioned inside the opening edge 1a of the box body 1.
And a fixing part 5 fixed to the back surface of the lid 2 together with one piece of the reinforcing metal fitting 7, and an abutting part 6 bent so as to be convex to the outside of the other piece of the reinforcing metal fitting 7 extending from the fixing part 5. 3 and 3. In this case, this shield fitting 3
As shown in FIGS. 6 to 8, a fixing portion 5 formed of phosphor bronze and having bolt insertion holes 4 formed therein, and a contact portion 6 extending upward from one end of the fixing portion 5. Consists of. The abutting portion 6 is divided into a number of substantially V-shaped cross-sections protruding outward, and one end portion in the extending direction is bent.
Then, the shield fitting 3 is fixed to the lid 2 in combination with the reinforcing fitting 7 as shown in FIG. Specifically, the reinforcing metal fitting 7 is made of, for example, stainless steel and has a cross-sectional shape of L.
It has a bolt insertion hole 8 communicating with the bolt insertion hole 4 of the shield metal fitting 3 in the shape of a letter, and a bolt 9 is inserted into these bolt insertion holes 4 and 8 to attach the shield metal fitting 3 to the lid 2 to the lid 2. Fix it (Fig. 3). In this case, both ends of the contact portion 6 are supported by both ends of the other piece of the reinforcing metal fitting 7, and one end of the other portion of the reinforcing metal fitting 7 is supported by one end of the contact portion 6 bent as described above. Is held, and in this state, the contact portion 6 is pressed against the inner peripheral surface of the opening edge portion 1a. This prevents external electromagnetic waves from entering the box. In addition,
The upper end of the opening edge portion 1a is bent at a substantially right angle, and a packing 12 is interposed between the lid 2 and the lid 2. Also, the box body 1
As shown in FIG. 10, an iron plate 10 is provided on the bottom surface of the so as to form a space between the iron plate 10 and the bottom surface, and is fixed with bolts 11.

[Effect of device]

According to the electromagnetic shield box of the present invention, the abutting portion of the shield metal member is bent so as to be convex to the outside of the other piece of the reinforcing metal member, and the abutting portion is elastically attached to the opening edge portion of the box body. Since the structure is pressed against the inner surface, external electromagnetic waves will not enter the box. Therefore, the operation of the electronic circuit device mounted in the box becomes good. In this case, since the contact portion is inserted into the inner peripheral surface of the opening edge portion, the lid can be mounted without rattling without being affected by the member pressing the lid toward the box body side. Further, since both ends of the contact portion are supported by both ends of the other piece of the reinforcing metal fitting, it is possible to suppress the inward bending of the contact portion due to the reaction force received from the opening edge portion of the box body. For this reason, the contact portion has high adhesion even after long-term use, and external electromagnetic waves can be further blocked. Furthermore, since one end of the contact portion in the extending direction is bent to hold the other end of the reinforcing metal fitting,
The contact portion does not bend outward due to external force, etc., and smoothly enters the inside of the opening edge portion.

[Brief description of drawings]

FIG. 1 is a front view of an electromagnetic shield box according to an embodiment of the present invention, FIG. 2 is a side view thereof, FIG. 3 is an enlarged sectional view of an essential part thereof, FIG. 4 is a front view of a box body, and FIG. Is a rear view of the lid, FIG. 6 is a side view of the shield metal fitting, FIG. 7 is a front view thereof, FIG. 8 is a plan view thereof, FIG. 9 is a front view of a reinforcing metal fitting, and FIG. It is a XX sectional view. 1 ... Box body, 2 ... Lid, 3 ... Shield fitting

Claims (1)

[Scope of utility model registration request] 1. A box main body having an opening on the front surface, a lid arranged on the front surface of the box main body, one piece fixed to the back surface of the lid, and the other piece positioned inside the opening end edge portion of the box main body. From the fixing portion, the reinforcing metal fitting having the L-shaped cross section and the fixing portion fixed to the back surface of the lid together with one piece of the reinforcing metal fitting and bent so as to be convex to the outside of the other piece of the reinforcing metal fitting. An extending shield metal fitting, wherein both ends of the abutting portion are supported by both ends of the other piece of the reinforcing metal fitting, and one end portion of the abutting portion in the extending direction is bent to form the reinforcing metal fitting. The electromagnetic shield box, wherein the abutting portion is pressed against the inner peripheral surface of the opening edge portion while holding one end portion of the other piece.