JP2540392B2 - Cable frame structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable shield frame ground structure, and more particularly to a cable shield frame ground structure connected to a card edge pattern of a printed board through an edge connector.

[0002]

2. Description of the Related Art The shield of a shielded cable must be grounded to the same potential as the frame of the electric device to which it is connected, which is called the frame ground to distinguish it from the ground of the signal line. In order to reduce the contact resistance as much as possible, it is necessary for the connecting portions of the frame grounds to reliably contact the conductors in a large area.

Conventionally, as a grounding structure for a shield of a cable, as shown in FIG. 5, the outer insulating coating (sheath) of the cable 11 is peeled off to expose a part of the shield net assembly (shield of the net assembly structure) 13. There is known a structure in which this portion is sandwiched between the pressing metal fitting 25 and the metal frame 3 and tightened with the screw 26 to simultaneously fix the frame gland of the shield net assembly 13 and the cable 11.

As another structure, as shown in FIG.
Adopting the connector-to-connector connection structure, the metal connector cover of the device side connector 27 is attached to the metal front plate 28.
And connect the shield mesh of the cable 11 to the metal connector cover of the cable side connector 29 so that the metal connector covers contact each other when the cable side connector 29 is connected to the device side connector 27. Then, there is known a structure in which the shield mesh set of the cable 11 is connected to the metal frame 3 which fixes the printed board 1 via the metal front plate 28.

[0005]

The former structure shown in FIG. 5 has the advantage that the structure is simple, but the cable 1
1 must be provided with a sheath peeling portion,
In addition, since the pressing metal fitting 25 has to be tightened or removed one by one when the cable 11 is attached or detached, there is a disadvantage in that it takes a lot of trouble in assembling or maintaining.

On the other hand, the latter structure shown in FIG. 6 is convenient when the partner to which the cable 11 is connected is a power supply unit or a disk drive unit having a metal case, but the partner to which the cable 11 is connected is a printed board. When the number is 1, the metal front plate 28 must be fixed to the printed board 1 and the device-side connector 27 must be attached, which increases the number of parts and the number of assembling steps, resulting in an increase in the manufacturing cost of the device.

According to the present invention, the shield of the shielded cable connected to the printed board through the edge connector is provided at the same time as the insertion of the connector without causing the above-mentioned complicated operation and increase in the number of parts or the assembly man-hour. The challenge is to obtain a technical means in which the cable shield is frame grounded.

[0008]

According to the present invention, notches 6 having narrow opening sides are provided on both sides of a card edge pattern 4 of a printed board 1 to which a cable 11 is to be connected. A conductive pattern 7 connected to the frame ground pattern 8 of the printed board 1 is provided on at least a cutout end surface 5 of the cutout on a side far from the card edge pattern 4. The frame ground pattern 8 is the printed board 1
When fixed, it is electrically connected to the metal frame.

The connector cover 10 of the edge connector 9 connected to the printed board 1 is provided with metal plate springs 21 urged in the projecting direction at both end portions thereof so that the connector cover 1
The clamp metal fitting 14 that clamps the shield 13 of the cable 11 within 0 is electrically connected to the metal leaf spring 21.

[0010]

The shield 13 of the cable 11 is clamped by the clamp metal fitting 14 inside the connector cover 10, and the metal member (the connector cover of the illustrated embodiment) 10 electrically connecting the clamp metal fitting and the metal leaf spring 21. It is connected to the metal leaf spring 21 via. The metal leaf spring 21 is biased outwardly, and when the edge connector 9 is inserted into the card edge pattern 4 of the printed board 1, the metal leaf spring 21 is cut out on both sides of the card edge pattern 4. 6 and the metal leaf spring 21 is pressed against the notched end face 6 provided with the conductive pattern 7 by its own spring force. Therefore, the metal leaf spring 21 has the conductive pattern 7,
The metal frame 3 holding the printed board 1 is grounded via the frame ground pattern 8.

The connector cover 10 is usually provided with a locking means for preventing the connector from falling off due to vibration or the like. In the structure of the present invention, the metal plate spring 21 is provided.
Since the notch 6 into which is inserted is narrowed on the opening side, engagement of the metal leaf spring 21 and the notch 6 prevents the connector cover 10 from falling off. Since it also serves as a fall prevention structure, it is possible to avoid an increase in the number of parts and the number of assembling steps for processing the cable frame ground.

Further, the cable 1 is detached by detaching the connector 9.
Since one frame ground process is also performed at the same time, workability during assembly and maintenance is also good. The structure of the present invention can be applied not only to a commonly used shield having a braid structure but also to a shield having a vapor deposition structure or a foil structure.

[0013]

EXAMPLE An example shown in the drawings will be described below. In FIG. 1, reference numeral 1 denotes a printed board, which is fixed to a metal frame 3 of an electric device by a screw 2. The cable connection portion of the printed board 1 is provided with a card edge pattern 4, and on both sides thereof, a notched trapezoidal notch 6 in which a notched end surface 5 on the side far from the card edge pattern 4 has an inverse slope is provided. Has been. The width of the cutout 6 on the opening side is narrower than the width on the back side because the cutout end surface 5 has a reverse slope.

As shown in FIG. 3, a conductive pattern 7 is provided on the outer notched end surface 5, and a frame ground pattern 8 connected to the conductive pattern 7 extends to the mounting position of the board mounting screw 2. There is. When the printed board 1 is fixed to the metal frame 3 with the screw 2, the frame ground pattern 8 is electrically connected to the metal frame 3.

The edge connector 9 connected to the card edge pattern 4 is housed in a metallic connector cover 10, and the end of the cable 11 connected to this has a sheath peeling portion 12 inside the connector cover 10. The shield net assembly 13 is provided and is exposed. The end portion of the cable 11 is fixed to the metallic connector cover 10 by the clamp metal fitting 14 with the screw 2 in the exposed portion of the shield net assembly 13, and the external force acting on the cable 11 is
It is received by the clamp metal fitting 14, and the shield net assembly 13 is electrically connected to the connector cover 10 at this clamp portion.

The side surface of the connector cover 10 has a double wall structure, and the outer wall 17 thereof is provided with openings 18 and 19 at its tip and base ends. A metal leaf spring 21 is arranged between the outer side wall 17 and the inner side wall 20, and the engaging portion 22 is opened from the opening 18 at the tip end and the operation portion 2 is opened from the opening 19 at the base end.
3 is protruding. The tip of the metal leaf spring 21 is movably locked to the tip of the side portion of the connector cover 10, and as shown in FIG. 4, a spring piece 24 extends from the operating portion 23 and contacts the inner wall 20, The entire metal leaf spring 21 is biased outward. The engaging portion 22 of the metal leaf spring 21 has an inversely sloped shape with a large amount of protrusion on the tip side,
It matches the shape of the reverse slope of the notch end surface 5 outside the notch 6 of the printed board.

In the above structure, when the edge connector 9 is inserted into the card edge pattern 4 of the printed board, the engaging portion 22 of the metal leaf spring is pushed by the notch end surface 5 outside the notch and bent slightly inward. In this state, the metal plate spring 21 is inserted into the notch 6 and pressed against the conductive pattern 7 provided on the notched end face 5 of the outer edge by the elasticity of the metal leaf spring 21. Therefore, when the edge connector 9 is inserted into the card edge pattern 4, the shield net assembly 13 of the cable 11 includes the clamp metal fitting 14, the metal connector cover 10, and the metal leaf spring 2.
It is connected to the conductive pattern 7 via 1 and is electrically connected to the metal frame 3 via the frame ground pattern 8. At the same time, the engagement between the engaging portion 22 of the metal leaf spring having a reverse slope and the outer cutout end surface 5 provides resistance to the edge connector 9 coming off.

When the edge connector 9 is detached, the operating portion 23 of the metal leaf spring is pinched by the fingertip and pushed in, so that the engaging portion 22 of the metal leaf spring bends so as to be pulled toward the inner wall 20 side. When the connector cover 10 is pulled out in this state, the engagement between the engaging portion 22 and the cutout end surface 5 is released, and the edge connector 9 is pulled out.

[0019]

As described above, according to the structure of the present invention, the shield of the cable connected to the printed board can be grounded to the metal frame of the device to which the printed board is attached, and the connector can be connected. Since the frame frame of the cable is realized only by inserting,
Workability during assembly and maintenance is greatly improved. Further, the connector retaining structure and the frame ground structure can be performed by a common member, and there is an effect that the frame ground process of the cable can be reliably performed at the minimum cost.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention with a cross section of a connector cover.

FIG. 2 is a side view of the connector cover.

FIG. 3 is an enlarged perspective view of a notch provided on a printed board.

FIG. 4 is an enlarged perspective view of a metal leaf spring.

FIG. 5 is a front view showing a first conventional example.

FIG. 6 is a perspective view showing a second conventional example.

[Explanation of symbols]

 1 Printed board 3 Metal frame 4 Card edge pattern 5 Notched end face 6 Notch 7 Conductive pattern 8 Frame ground pattern 9 Edge connector 10 Connector cover 11 Cable 13 Shield braid 14 Clamp metal fitting 21 Metal leaf spring

Claims (1)

(57) [Claims] 1. In the frame ground structure of the shield (13) of the shielded cable (11) connected to the printed board (1), the opening side is narrowed on both sides of the card edge pattern (4) of the printed board (1). A cutout (6) is provided, and a conductive pattern (7) is provided on at least the cutout end surface (5) far from the card edge pattern (4) of this cutout, and this conductive pattern is provided on the printed board.Frame ground pattern (8) A metal frame that holds the printed board (1) in place via
The metal leaf springs (21) that are biased in the protruding direction are attached to both ends of the connector cover (10) of the edge connector (9) that is electrically connected to (3) and is connected to the card edge pattern (4). Provided,
Inside the connector cover (10), clamp metal (14) that clamps the shield (13) of the cable (11) and the metal leaf spring (2)
1) A cable frame ground structure characterized by being electrically connected to and.