JPH1126094A - Cable radiation noise suppressing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the impedance between the shield of a coaxial cable and the ground and to reduce the radiation noise from the coaxial cable by covering a coaxial cable housing on a digital system mounting type back board from above with a metal adapter. SOLUTION: An adapter 20 is split into two portions 20a, 20b along a split line which connects the centers of pinch holes 21 to be inserted with coaxial cables. Pinch springs are provided at the portions facing the pinch holes 21 across a split line 22. The coaxial cables are located on the pinch holes 21 and are pinched by the portions 20a, 20b of the adapter 20, and hooking hooks 24 and hooking pins 25 are integrally coupled. When the hooking pawls 26 of the adapter 20 are inserted into hooking holes 2a, the adapter 20 is put over an coaxial cable housing. Also cable connectors of the coaxial cables are pinched by the pinch springs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cable radiation noise suppression mechanism, and more particularly to a method of connecting a shielded coaxial cable to a backboard in a digital system mounting system.

[0002]

2. Description of the Related Art Conventionally, in a digital system mounting system, a plurality of units are mounted on a frame, a plurality of packages are mounted on one surface of a back board of the unit, and the other surface of the back board is mounted. To a shielded coaxial cable.

When connecting a shielded coaxial cable to the backboard, the connection is made via a plastic housing. The shield of the shielded coaxial cable is connected by crimping to a connector, and the electrical connection is made. Conduction is possible.

In the above method, the backboard and the shielded coaxial cable are connected by using a plastic housing provided on the backboard. When the backboard and the shielded coaxial cable are connected, the ground in the package is connected to the ground. Although connected, the housing supporting the shielded coaxial cable is made of plastic, so it is not connected to the frame ground of the unit on the rack side.

In this case, since the shield of the shielded coaxial cable is in a floating state (not connected) on the rack side, the shield effect is reduced. In particular, when the package is not connected, noise is radiated from the cable connecting between the devices and between the units, which may cause malfunction of other devices.

In order to solve this problem, when connecting (grounding) the shield of the interface cable to the ground, the method of connection using a Faston terminal, a lead wire, a crimp terminal, and a screw is improved, and a metal plate is used. There is a technique for reducing the number of parts and lowering the impedance. Regarding this technology, see Japanese Utility Model Application Laid-Open No. 64-219.
No. 81 discloses this.

That is, in the technique described in this publication, FIG.
As shown in FIG. 7, in a mechanism for connecting the shield of the interface cable 51 to the board pattern 56 of the base plate (ground) 60 via the connector metal part 52, a metal plate 57 is provided between the connector metal part 52 and the base plate 60. This arrangement lowers the impedance between the shield and the ground, and lowers the level of radiated noise.

In this case, the metal plate 57 is screwed to the base plate 60 via the printed circuit board pattern 56.
, And the connector 54 is connected to a printed circuit board pattern 56 via a ground contact piece 55.

When the base 53 of the interface cable 51 is fitted to the connector 54, the connector metal part 52 comes into contact with the claw 58 of the metal plate 57, so that the connector metal part 52 is connected to the base plate 60 via the metal plate 57. It will be connected.

[0010]

In the above-described conventional cable radiation noise suppressing mechanism, the metal plate 57 is fixed directly to the printed circuit board by screws, so that the metal plate 57 is used as an internal component of the apparatus. Will be configured. Therefore, the metal plate must be assembled at the time of manufacturing the product, and the metal plate 57 cannot be assembled after the product is manufactured, that is, the existing product.

Further, since the base plate 60 in which a ground pattern is wired on a printed circuit board is used as the ground, the impedance becomes higher when this system is used in a digital system mounting system than when the frame ground of the unit is used. And the shielding effect is reduced.

Therefore, a first object of the present invention is to solve the above-mentioned problems, to be able to be incorporated in an existing device, and to reduce the impedance as compared with the case where a base plate on which a ground pattern is wired is used. Can,
A second object of the present invention is to provide a cable radiation noise suppressing mechanism capable of improving a shielding effect, which can be incorporated into an existing transmission line in operation without interrupting operation. It is to provide a noise suppression mechanism.

[0013]

A cable radiation noise suppression mechanism according to the present invention is provided on one surface and has a plurality of first connectors to which a plurality of packages are electrically connected, and a plurality of connectors provided on the other surface and has a plurality of packages. A backboard including a plurality of second connectors to which each of the coaxial cables is electrically connected, and a cable radiation noise suppression mechanism for an electronic device comprising a unit accommodating each of the plurality of packages, A plurality of connection members covering a front surface of a second connector and electrically connecting a shield ground of the coaxial cable and a frame ground of the unit;
A metal adapter that holds each of the plurality of connection members and is detachable from the backboard.

That is, in the cable radiation noise suppression mechanism of the present invention, a metal adapter is put on a coaxial cable housing on a back board of a digital system mounting system from above, and the metal adapter is mounted on a support hardware attached to the back board. Attach.

By this, the ground is strengthened by bringing the connector of the shielded coaxial cable into contact with the frame ground of the unit through the metal adapter, so that the impedance between the shield and the ground of the shielded coaxial cable can be reduced. Therefore, radiation noise from the shielded coaxial cable can be reduced.

In this case, since the metal adapter can be retrofitted after the product is manufactured, it can be incorporated into an existing device, and the impedance is reduced as compared with the case where a base plate on which a ground pattern is wired is used. And the shielding effect can be improved.

[0017] Also, a backboard provided with a first connector on one side to which a package is electrically connected and a second connector on the other side to be electrically connected to a coaxial cable are provided. A cable radiation noise suppression mechanism for an electronic device comprising a unit that houses the package, further comprising a conductive adapter that covers a front surface of the second connector, wherein the adapter is a shield ground of the coaxial cable. And a connection means for electrically connecting the frame ground of the unit to the support metal of the backboard. The connection means can be detachably attached to the support hardware of the backboard, and can be divided in the direction of sandwiching the shield ground of the coaxial cable. I have.

When the adapter is mounted on a coaxial cable, the adapter is attached so that the shield ground is held between the divided portions, and is attached to the support hardware. For this reason, it can be attached to a coaxial cable already connected to the second connector, and can be incorporated into an existing transmission line in operation without interrupting operation.

[0019]

Next, a cable radiation noise suppressing mechanism according to the present invention will be described in detail with reference to a preferred embodiment shown in the drawings. First, the embodiment shown in FIGS. 5 to 8 will be described.

FIG. 5 is a perspective view of one embodiment of the present invention.
In the figure, an appropriate number of support hardware 2 is fixed in parallel to a back board 1 of a digital system type unit, and a suitable number of coaxial cable housings 3 constituting a second connector are fixed to the support hardware 2. Mounted. On the surface of the backboard 1 opposite to the side on which the coaxial cable housing 3 is provided, a package housing 4 constituting a first connector is mounted.
The coaxial cable housing 3 has an appropriate number of insertion holes 3a for connecting the shielded coaxial cable 5 (shown in FIG. 6). The package housing 4
Is connected to the connector 6a of the package 6. The connectors 6a are arranged in a suitable number as necessary, and a package 6 is connected to each of these connectors 6a to form a unit.

And the coaxial cable housing 3
Adapter 7 having conductivity by being made of metal or the like
Is covered. The adapter 7 has a holding hole 7a formed at a position corresponding to the insertion hole 3a when the adapter 7 is covered with the coaxial cable housing 3. Adapter 7
On the upper and lower ends of the back surface of the rear surface, a locking claw 7b as a claw member composed of a pair of hook members is provided. On the other hand, the adapter 7 is mounted on the coaxial cable housing 3 on the support metal member 2. A locking hole 2a is formed at a position where the locking claw 7b reaches. Then, with the locking claws 7b inserted into the locking holes 2a, the pair of hook members are engaged with the support hardware 2, and the adapter 7 is maintained in a state of covering the coaxial cable housing 3. Further, a metal holding spring 8 as a holding means is provided on the back surface of the adapter 7 at a position sandwiching the holding hole 7a at an edge of the holding hole 7a. With the coaxial cable 5
Of the cable connector 5a is held by the holding spring 8. The portion of the holding spring 8 facing the holding hole 7a is formed in an arc shape so that the coaxial cable 5 can be smoothly inserted and removed.

The operation of the embodiment of the cable radiation noise suppressing mechanism according to the present invention configured as described above will be described below.

When the adapter 7 is put on the coaxial cable housing 3 and the locking claws 7b are inserted into the locking holes 2a, they are engaged and the adapter 7 is attached to the support hardware 2 and the cable housing 3 Is maintained. The holding hole 7a of the adapter 7 and the insertion hole 3a of the coaxial cable housing 3 match. In this state, the coaxial cable 5 is inserted into the holding hole 7a and the insertion hole 3a, and the cable connector 5a is held by the holding spring 8. Thereby, the cable connector 5a and the adapter 7 can make reliable electrical contact.

Since the adapter 7 is attached to the support hardware 2, the shield portion of the coaxial cable 5 is reliably conducted to the frame ground of a unit (not shown) via the cable connector 5a, the adapter 7, and the support hardware 2. You. Therefore, the shielded coaxial cable 5
Impedance between the shield part and the unit can be reduced.

Moreover, since the adapter 7 is attached to the support hardware 2 by inserting the locking claws 7b into the locking holes 2a, the adapter 7 can be easily attached and detached, and not only new devices but also existing devices can be used. It can also be attached to equipment.

Next, a cable radiation noise suppressing mechanism according to the embodiment shown in FIGS. 1 to 4 will be described. FIG.
The same members and portions as those of the embodiment shown in FIG. 8 are denoted by the same reference numerals, and description thereof will be omitted. The adapter 20 according to this embodiment includes a holding hole 21 through which the coaxial cable 5 is inserted.
Are divided into two parts 20a and 20b along a straight line 22 connecting the centers of the two. A clamping spring 23 is provided in a portion facing the clamping hole 21 with the dividing line 22 therebetween. The adapter 20 is provided with a hook 24 on one side and a locking pin 25 on the other side for engaging and disengaging the hook 24. Adapter part
20a and 20b are integrally held. At the upper and lower ends of the rear surfaces of the adapters 20a and 20b, locking claws 26 similar to the locking claws 7b are provided.

In the embodiment shown in FIGS. 1 to 4, the coaxial cable 5 is positioned in the holding hole 21, and the coaxial cable 5 is held by the respective portions 20a and 20b of the divided adapter 20. While these parts 20a,
The engaging hook 24 and the engaging pin 25 of 20b are engaged to be integrated. When the locking claw 26 of the integrally formed adapter 20 is inserted into the locking hole 2a, the adapter 20 is put on the coaxial cable housing 3, and this state is maintained. . Also, each part 20a, 20
When b is integrated, the cable connector 5a of the coaxial cable 5 is held by the holding spring 23. As a result, the cable connector 5a and the adapter 20 can make reliable electrical contact.

In the embodiment shown in FIGS. 1 to 4,
The adapter 20 is composed of the respective parts 20a and 20b,
By integrating them, the coaxial cable 5 is sandwiched, so that the adapter 20 can be covered on the coaxial cable housing 3 without removing the coaxial cable 5 from the coaxial cable housing 3. The adapter 20 can be incorporated into an existing transmission line in operation without stopping the operation.

[0029]

As described above, according to the present invention, a plurality of first connectors provided on one surface and to which a plurality of packages are electrically connected, and a plurality of coaxial cables provided on the other surface are provided. A plurality of second each electrically connected
In a cable radiation noise suppression mechanism for an electronic device, comprising a backboard including a connector and a unit accommodating a plurality of packages, a front surface of a second connector is covered, and a shield ground of a coaxial cable and a frame of the unit are provided. By providing a plurality of connecting members for electrically connecting the ground and a metal adapter which holds each of the plurality of connecting members and is detachable from the backboard, it can be incorporated into an existing device, There is an effect that the impedance can be reduced and the shielding effect can be improved as compared with a case where a base plate on which a pattern is wired is used.

Also, since the adapter is divided and the respective components are integrated to sandwich the shield ground of the coaxial cable, the coaxial cable forming the transmission line in operation is connected to the second coaxial cable. The second connector can be covered with the adapter without being removed from the connector. Therefore, the impedance can be reduced, and the shielding effect can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic exploded perspective view illustrating the structure of an embodiment of a cable radiation noise suppression mechanism according to the present invention.

FIGS. 2A and 2B are views showing the adapter according to the embodiment shown in FIG. 1, wherein FIG. 2A is a front view and FIG.

FIGS. 3A and 3B are views showing the adapter according to the embodiment shown in FIG. 1, wherein FIG. 3A is an exploded perspective view seen from the front side, and FIG.

FIG. 4 is a longitudinal sectional view of a center part of the adapter according to the embodiment shown in FIG. 1, in which a shielded coaxial cable is also shown.

FIG. 5 is a schematic exploded perspective view illustrating the structure of another embodiment of the cable radiation noise suppression mechanism according to the present invention.

6A and 6B are views showing the adapter according to the embodiment shown in FIG. 5, wherein FIG. 6A is a front view and FIG. 6B is a right side view.

FIGS. 7A and 7B are views showing the adapter according to the embodiment shown in FIG. 5, wherein FIG. 7A is a perspective view seen from the front side, and FIG.

FIG. 8 is a longitudinal sectional view of a center portion of the adapter according to the embodiment shown in FIG. 5, in which a shielded coaxial cable is also shown.

FIG. 9 is a diagram showing an assembling example of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Backboard 2 Support hardware 2a Locking hole 3 Coaxial cable housing (second connector) 3a Insertion hole 4 Package housing (first connector) 5 Shielded coaxial cable 5a Cable connector 6 Package 7 Adapter 7a Holding hole 7b Locking claw 8 Holding spring 20 Adapter 21 Holding hole 22 Dividing line 23 Holding spring 24 Locking hook 25 Locking pin 26 Locking claw 51 Interface cable 52 Connector metal part 53 Base 54 Connector 55 Grounding piece 56 Printed circuit board pattern 57 Metal Plate 58 Claw 59 Screw 60 Base plate

Claims (7)

[Claims] 1. A plurality of first connectors provided on one surface and electrically connected to each of a plurality of packages, and a plurality of first connectors provided on another surface and electrically connected to each of a plurality of coaxial cables. A cable radiation noise suppression mechanism for an electronic device, comprising a back board including a second connector and a unit that stores each of the plurality of packages, wherein the front surface of the second connector is covered and the A cable comprising: a plurality of connection members for electrically connecting a shield ground and a frame ground of the unit; and a metal adapter which holds each of the plurality of connection members and is detachable from the backboard. Radiation noise suppression mechanism. 2. The cable radiation noise suppression mechanism according to claim 1, wherein each of the plurality of connection members is formed of a metal elastic member that sandwiches a shield ground of the coaxial cable. 3. The cable according to claim 1, wherein the metal adapter includes a claw member that is locked by a locking hole provided at a corresponding position on the backboard. Radiation noise suppression mechanism. 4. A back board provided with a first connector to which a package is electrically connected on one surface and a second connector to which a coaxial cable is electrically connected on the other surface. A cable radiation noise suppression mechanism for an electronic device comprising a unit that houses the package, further comprising a conductive adapter that covers a front surface of the second connector, wherein the adapter is a shield ground of the coaxial cable. A connection means for electrically connecting the backboard and a frame ground of the unit, and the cable radiation noise suppression mechanism being detachable from a support hardware of the backboard. 5. A back board provided with a first connector to which a package is electrically connected on one surface and a second connector to which a coaxial cable is electrically connected on the other surface. A cable radiation noise suppression mechanism for an electronic device comprising a unit that houses the package, further comprising a conductive adapter that covers a front surface of the second connector, wherein the adapter is a shield ground of the coaxial cable. And a connection means for electrically connecting the frame ground of the unit and the frame ground of the unit. The connection means can be detachably attached to the support hardware of the backboard, and can be divided in the direction of sandwiching the shield ground of the coaxial cable. Cable radiation noise suppression mechanism. 6. The connector according to claim 1, wherein said connection means is a locking claw that is detachable from said support hardware and maintains said adapter covered by said second connector when engaged. The cable radiation noise suppressing mechanism according to claim 4 or 5. 7. The adapter according to claim 4, wherein the adapter includes a holding means made of a conductive elastic material for holding the shield ground of the coaxial cable. Cable radiation noise suppression mechanism.