JPH0745993Y2 - Structure of front shield plate in printed circuit board unit - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the structure of a front shield plate in a printed board unit.

[0002]

2. Description of the Related Art In recent years, electronic devices such as information processing devices have been
An expansion slot such as a bus slot is provided, and various printed board units are mounted in the slot to achieve desired expansion. Conventionally, as a printed board unit to be inserted into such a slot, the one shown in FIGS. 7 to 9 has been widely used.

This printed circuit board unit has a front shield plate 2 on the front surface of a printed circuit board 1 on which an edge connector 10 plugged into a connector (not shown) fixed to a back panel of the main body of the apparatus is mounted. It is configured and guarantees the electromagnetic environment when mounted in the slot. The front shield plate 2 is formed by tightening the leaf springs 7 together on the back surface of the plate-shaped member 11, and in order to establish conduction between the adjacent front shield plates 2, the leaf springs 7 have upper and lower end edges. A contact piece 9 is provided so as to project.

In FIG. 7, 12 is an external connector fixed to the front shield plate 2, 13 is a handle for improving the detachability of the printed board unit, and 14 is the front shield plate 2 fixed to the printed board 1. It is a fixture for doing.

[0005]

However, in the above-mentioned conventional example, since the contact piece 9 of the leaf spring 7 is formed in a cantilever shape, and the free end is mounted in the state of being exposed to the outside, In addition to being permanently deformed, electrical continuity between the front shield plate 2 and another adjacent front shield plate 2 is lost, and the printed circuit board 1
The lead part of the element mounted on the upper part comes into contact with the contact piece 9 of the adjacent front shield plate 2 to cause a short circuit, or the lead part is bent by the contact piece 9 when the printed board unit is mounted, resulting in a short circuit. It had the drawback of.

The present invention has been made to solve the above drawbacks, and an object of the present invention is to provide a structure of a front shield plate in a printed board unit having excellent shield performance.

[0007]

Above object, according to the present invention Means for Solving the Problems] As shown in FIG. 1, a structure of the front shield plate which is fixed to the front end edge of the printed circuit board 1, the front shield plate
Is a front wall of the surface plate 5 having a U-shaped cross section.
And is arranged on the entire back surface of the face plate 5, and is attached to the fixing tongue piece 15.
The back support plate 6 fixed to the printed circuit board 1 and the front surface
The plate spring 7 sandwiched between the plate 5 and the back support plate 6 is stacked.
The leaf spring 7 is formed by connecting the layers, and the leaf spring 7 has a surface.
For exposing springs that are opened at a predetermined pitch on the ceiling piece 3 of the face plate 6.
A generally V-shape to expose only the vicinity of the bent top 8 from the opening 4.
Printed board unit in which a contact piece 9 bent in a curved shape is projected
Reached by providing the structure of the front shield plate in
Is made.

[0008]

Based on the above construction, the front shield plate 2 according to the present invention is constructed by teaching the leaf spring 7 by the front plate 5 and the back support plate 6, and the contact piece 9 formed on the leaf spring 7 is It is exposed from the spring exposing opening 4 of the surface plate 5 and comes into contact with the bottom piece of another front shield plate 2 that is continuously provided, so that reliable shield performance is imparted. Further, the contact piece 9 of the leaf spring 7 is in a state in which only the bent top portion 8 thereof is exposed from the spring exposure opening 4, so that permanent deformation and the like due to abnormal contact are reliably prevented. It
In addition, the front wall of the front shield plate is the front plate 5, the back support plate.
6 and the leaf spring 7 are laminated bodies, so that the back support plate
By changing the plate thickness of 6 etc., the leading edge of the printed circuit board 1
It is possible to freely change the distance from the
Therefore, it is possible to easily comply with various standards.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 2 shows a printed circuit board unit to which the present invention is applied. In FIG. 2, reference numeral 1 denotes a printed circuit board having an edge connector 10 attached to the main body of the apparatus at its edge portion, and the other side. External connector 1 at the edge
2 is fixed.

The printed board unit formed by fixing the front shield plate 2 to the front surface of the printed board 1 is shown in FIG.
As shown in, the separation dimension L1 from the edge of the printed circuit board 1,
Also, the dimension L2 up to the surface portion of the front shield plate 2 is adapted to the standard value to ensure mechanical compatibility during mounting.

The front shield plate 2 includes a front plate 5, a leaf spring 7, and a rear surface so that the outer dimensions can be accommodated within the standard dimensions and the plate thickness of the mounting portion of the external connector 12 can be changed. The support plate 6 and the support plate 6 are overlapped with each other, and both ends are fixed to the fixing tool 14 fixed to the printed circuit board 1, and the central fixing tongue piece 15 is fixed to the printed circuit board 1. Has been done.

The back support plate 6 is, as shown in FIG.
It is a sheet metal member formed by cutting and raising the fixing tongue piece 15 in the central portion, and at both ends thereof, a through hole for a fastener (not shown) which is fastened together with the surface plate 5 and the leaf spring 7 to the fixture 14. 16 and an oval hole 18 through which a fastening piece 17 for fixing to the apparatus main body is inserted. Also, this insertion hole 16
A slot-like handle mounting hole 19 is formed in the vicinity of, and the handle 13 which serves as a handle when mounted on the apparatus main body is inserted and fixed in the handle mounting hole 19.

The front shield plate 2 in this embodiment is
It has one external connector 12, and the plate thickness of the mounting portion of the external connector 12 is set to be the total plate thickness of the surface plate 5 and the plate spring 7. ,
The back support plate 6 has an external connection connector 12 so that the plate thickness of the back support plate 6 does not substantially affect the plate thickness of the mounting portion.
A rectangular hole 21 into which the mounting plate 20 of 1 is completely fitted is opened. On the other hand, the surface plate 5, as shown in FIG. 6, is a metal plate member having a substantially U-shaped cross section, and has a handle mounting hole 19, an insertion hole 16 and an oval hole 18 in the vicinity of both ends thereof. A fitting hole 23 having a shape matching the fitting portion 22 of the external connector 12 is provided at a portion of the back support plate 6 corresponding to the rectangular hole 21. The ceiling piece 3 of the surface plate 5 is provided with spring exposing openings 4 at a predetermined pitch.

A leaf spring 7 formed in a shape substantially the same as the front view shape of the back support plate 6 has the front plate 5 at the upper edge thereof.
The contact piece 9 is bent in a substantially V shape so as to match the spring exposing opening 4. As shown in FIG. 1, the leaf spring 7 is mounted in a state of being sandwiched between the back support plate 6 and the front plate 5, and in the mounted state, the contact piece 9 is
The surface plate 5 is formed so as to project from the spring exposing opening 4, and only the vicinity of the bent top portion 8 of the contact piece 9 is exposed from the spring exposing opening 4 in order to prevent deformation during storage or mounting. The dimensions are set so that

Therefore, according to this embodiment, in the front shield plate 2, the contact piece 9 of the plate spring 7 is exposed from the spring exposing opening 4 of the surface plate 5, and a plurality of such printed board units are provided. When mounted, the bent top portion 8 of the contact piece 9 formed on the leaf spring 7 comes into contact with the bottom piece of the adjacent front shield plate 2, and the electromagnetic gap between the printed board units is closed.

[0017]

As is apparent from the above description, according to the structure of the front shield plate in the printed board unit according to the present invention, the contact piece of the leaf spring can shield the adjacent printed board units. Moreover, since the leaf spring is not permanently deformed by an external force, it is possible to exhibit good shielding performance for a long period of time.

[Brief description of drawings]

FIG. 1 is a view showing an essential part of the present invention.

FIG. 2 is a view showing a printed board unit to which the present invention is applied.

FIG. 3 is a view on arrow A in FIG.

FIG. 4 is a diagram showing a back support plate.

FIG. 5 is a diagram showing a leaf spring.

FIG. 6 is a view showing a surface plate.

FIG. 7 is a diagram showing a conventional example.

8 is a front view of FIG. 7. FIG.

9 is a side view of FIG. 7. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Front shield plate 3 Ceiling piece 4 Spring exposure opening 5 Front surface plate 6 Back surface support plate 7 Leaf spring 8 Bend top 9 Contact piece

Claims (1)

[Scope of utility model registration request] 1. A structure of a front shield plate fixed to a front edge of a printed circuit board, wherein a front wall of the front shield plate is a front wall of a front plate having a U-shaped cross section, and a back face of the front plate. It is placed on the entire surface, and the tongue for fixation
The back support plate fixed to the board and the leaf spring sandwiched between the front plate and the back support plate are stacked.
The leaf springs are formed on the ceiling piece of the face plate at a predetermined pitch while being formed by connecting the layers.
Only the vicinity of the bent top should be exposed from the spring exposure opening.
The structure of the front shield plate in the printed circuit board unit in which the contact pieces bent in a roughly V shape project .