MXPA99006691A - In-service removable cable ground connection - Google Patents

Abstract

The body of a connector assembly is attached to the ground of a cable internally disposed within an enclosure. The connector body has a radial flange positioned on the outside surface of the enclosure and a nut, threaded onto a portion of the connector extending internally into the enclosure, is used to secure the connector body whereby a ground connection is established between the connector body and the enclosure. The enclosure panel on which the body is mounted is connected to ground. A mating connector is attachable to a portion of the connector body extending outwardly from the enclosure. In normal service, the slot in which the connector assembly is mounted is covered. However, when necessary to access the interior of the enclosure, the connector and attached cables can be removed from the enclosure panel by removing the cover, loosening the nut disposed on the internal end of the connector body, and sliding the assembled connector and cable pair out of the slot. The connector, and cable pair attached thereto, can be moved out of the way without separation or disconnection. This invention addresses the problem of requiring disconnection of mating cable pairs when performing maintenance, inspection, repair, or other activity on enclosed electronic components such as the base station of a mobile telephone system.

Description

CONNECTION TO REMOVABLE CABLE GROUND IN SERVICE BACKGROUND OF THE INVENTION Technical Field This invention relates, in general, to an electrical connector for transmitting electrical signals from a cable connected to a side of a grounded panel or panel to a coupling connector, and more particularly, to a connector that It can be separated from the bulkhead or panel without disconnecting the coupling cable or connector.

BACKGROUND OF RELATED ART Earthed cables, such as coaxial cables having a separate braided shield or external shield or wired, separated wire, are used in multiple applications to conduct electrical signals between electronic components located in separate spaces . For example, in cellular telephone systems, one or more pairs of cables are used to transfer voice and data between a base station and a mobile telephone switching office. The electromagnetic emissions generated inside the box of the base station are carried out of the box by the interconnecting cables. One method of reducing radiated electromagnetic emissions from cables includes incorporating ferrite devices into the cable structure. These devices are based on the use of ferrites in the form of powder, compressed or sintered, making use of their ferrimagnetism and high electrical resistivity, which makes the losses by extremely low parasitic currents at high frequencies. However, it has been found that ferrites do not guarantee adequate attenuation than electromagnetic emissions at lower frequencies. An alternative method to reduce radiated electromagnetic emissions includes grounding the cables, more specifically grounding the braided cover that surrounds the signal conductor in the coaxial cables, or another member grounded in the cable as a terminal wire. Grounding the cables as they come out of the boxes, by means of a grounded bulkhead connector, has found an effective way to reduce radiated electromagnetic emissions from the cables used to connect a base station to the external equipment. The traditional bulkhead connectors, previously attached to the internal cable, must be inserted through a hole in a panel and secured by a threaded nut in the connector from the outside of the box. This requires that a mating cable be disconnected from the bulkhead connector to separate the bulkhead connection and access the components clogged by the cable and connector. This requires that the base station be taken out of service during any maintenance procedure that requires separation from the front panel. In addition, the restriction on the size of a base station and the requirement of easy accessibility to the internal components for maintenance makes the use of standard plug connectors undesirable. Therefore, it is desirable to have a grounded connection of a removable cable that allows separation of the front panel or other access panels without requiring that the connection between the electronic components placed inside and outside be disconnected and put out of service . Also, it is also desirable to have a connector that can be easily separated from the panel without the use of wrenches, special tools or other devices.

BRIEF COMPENDI OF THE INVENTION According to one aspect of the present invention, a grounded connection for a cable having a grounding member includes a first grounded panel that provides a wall surface and a second panel that can placed in relation at least partially superimposed with a predefined portion of the first panel. The first panel has at least one edge - which is exposed in response to the separation of the second panel from the overlap relationship, and also has a groove extending inward from the edge to a position spaced from the end. The ground connection also includes an electrical connection unit having a body that can be electrically connected to the cable grounding member and adapted to be received within the slot provided in the first panel. The body of the connection assembly has a first end portion threaded on the outside, a second end portion and a radial flange extending outwardly from the body at a position between the first and second end portions. The electrical connection assembly also includes a threaded member in the interior that can be attached to the first end of the body and arranged to secure the body to the first panel in response to the tightening of the threaded member in the interior on the first externally threaded end portion of the body. When tightened, the internally threaded member is maintained in electrical contact, tightly spliced, derived or polarized, with a defined internal surface of the first panel and the radial flange of the body is maintained in electrical contact, tightly spliced, derived with the defined external surface of the first panel. Other characteristics of the ground connection for a cable having a grounding member, according to the present invention, includes the electrical connection assembly also with a coupling connector that is adapted to be clisable with the second end portion of the cable. body of the electrical connector. Other features include the internally threaded member and the mating connector of the connection assembly each with a knurled external surface adapted for manual installation in, and spacing from, the respective end portions of the body of the connection assembly. Still other features include the first end portion of the body of the connection assembly adapted for attachment to a coaxial cable having a braided cover, the first panel being a side wall of a box for a mobile station in a mobile telephone system, and the second panel being a front cover for the mobile station box.

BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of the structure and operation of the present invention can be had with reference to the following detailed description when taken together with the accompanying drawings, wherein: Figure 1 is a three-dimensional view of a box provided with a ground connection for a cable connector, in accordance with the present invention; Figure 2 is an exploded three-dimensional view showing the components of the ground connection incorporating the present invention, in spaced relation to each other; Figure 3 is a three-dimensional view of the electrical connection assembly of the ground connection for a cable having a grounding member, according to the present invention, showing the body of the connection assembly mounted on a panel of the box , and the coupling cable disconnected from the body; Figure 4 is an amplified three-dimensional view of the ground connection for a cable having a grounding member, in accordance with the present invention, showing the connection assembly assembled in a panel of the box; Figure 5 is a three-dimensional view of the box in which a ground connection for a cable having a grounding member, according to the present invention, is shown with the housing cover installed and a mating cable United; Figure 6 is an amplified three-dimensional view of the ground connection embodying the present invention, with an internal nut separated from the body of an electrical connector unit; and Figure 7 is a three-dimensional view of the electrical connector assembly of the ground connection for a cable having a grounding member, in accordance with the present invention, showing the electrical connection assembly separated from a mounting panel.

DETAILED DESCRIPTION OF THE INVENTION In the preferred embodiment of the present invention, a ground connection for a cable 10 having a grounding member is illustrated in the drawings in association with a box 12 adapted to house the different electronic components, such as they can be those that form the base station of a mobile phone system. These base stations usually have three or four pairs of cables that extend between the base station and a mobile telephone switching office and an antenna. Each pair of cables includes a cable 10 internal to the box of the base station, and a cable 10 'external to the box. All these cables 10, 10 'are usually coaxial in their construction, that is, they have a single signal wire placed at the center surrounded by insulation on which a braided cover surrounds the central wire and the insulation. Two pairs of cables, usually BNC connectors, are cables for pulse code modulation (PCM) that transfers voice and data between the base station and the mobile telephone switching office. In general, one or two additional pairs of cables use N connectors. If an additional pair of cables is used, this is usually a pair of transmit / receive cables that is connected to an antenna. If two additional pairs of cables are used, one is the pair of transmission / reception cables and the other is the pair of reception cables, each of which is connected to an antenna. The antenna transmits and receives voice and data to and from cellular subscribers. The pair of transmission / reception cables carry the voice and data to and from the base station. The pair of reception cables only carries voice and data to the base station. Although only a pair of cables 10, 10 'is shown in the accompanying drawings, the arrangement and construction of the removable cable ground connection described below is applicable to all these pairs of cables between the base station and the office Remote mobile telephony switching. In the illustrated arrangement of the preferred embodiment of the present invention, the box 12 includes a plurality of rectangular panels, including a side panel 14 and a removable front cover 16. The box 12 is grounded by the electrical connection with a ground connection 18 which can be provided by the ground wire from a three-pin power plug or, in another way, from an external ground source. In the internal cables, the braided cover of the coaxial cable 10 is connected, by conventional means, such as fastening, welding, or clamping, to a body 20 of an electrical connector unit 22. In the present invention, the body 20 of electrical connector assembly 22 may consist of a type of bulkhead connector of type N, BNC or other type. The electrical connection assembly further includes a knurled nut 24 and a coupling connector 26. It is desirable that the outer surface of the coupling connector 26 is also mole-plated to allow installation or separation by manual operation without the need for wrenches. nuts or other tools. As best seen in Figures 2 and 7, the body 20 of the electrical connection assembly 22 has a first externally threaded end portion 28, and a second end portion 30 that can be externally threaded, as shown in the drawing, or can be provided with other engagable surface features such as slots, recesses, pins, and the like, depending on the arrangement of the coupling connector 26. The body 20 of the electrical connection assembly 22 also includes a radial flange 32 extending outwardly from the body 20. in a position approximately halfway between the first and second end portions 28, 30. The grounded side panel 14 of the box 12 has an external flat surface 36 and a vertically placed edge 40 extending between the outer surface 36 and a surface internal flat that is not visible in the drawings. The vertical edge 40 may be provided by a flange extending towards the front of the box 12, as shown in the drawings, or it may be incorporated at one end of the panel 14 which is substantially aligned with the edges of the upper sides, bottom, and the other sides of the case 12. In the arrangement shown, the forwardly extending flange is received within a through hole provided in the front cover 16. When the front cover 16 is installed in the case 12, the vertical edge 40 and a portion of the outer surface 36 of the side panel 14 are covered by the front cover 16. As can easily be seen, the vertical edge 40 is exposed in response to the movement of the cover 16. It is important to note that, the grounded side panel 14 of the case 12 includes a groove 42 having a predetermined amplitude. The slot 42 extends inward from the vertical edge 40 to a position that separates from the edge 40 the portion of the slot 42, not occupied by the body 20 of the electrical connector assembly 22 when installed is covered when the panel front 16 is assembled in the box 12. If desired, a small, circular shoulder having a diameter substantially equal to that of the radial flange 32 of the body 20 may be provided on the inner vertical edge of the cover 16 in an aligned position with the body 20 when the cover 16 is assembled with the box 12. To assemble the removable ground connection embodying the present invention, the front cover 16 of the box 12 is separated and the electrical connection assembly 22, which consists of the knurled nut 24, the body 20 to which the inner cable 10 is attached and the coupling connector 26 to which the outer cable 10 'is attached, is installed in the groove 42 with the assembly components 22 arranged as shown in FIG. It is desirable that the first end portion 28 of the body 20 has a pair of parallel flat surfaces 44, only one of which is visible in the drawings., which are formed on opposite sides of a otherwise generally cylindrical threaded form. By this construction, the predetermined width of the groove 42 formed in the side panel 14 is smaller than the diameter of the generally cylindrical external shape of the body 20 and practically equal to, or only slightly greater than the distance between the parallel flat surfaces 44 in the body 20. In this way the body 20 is prevented from rotating with respect to the side panel 14 by the slot 42, and the knurled nut 24 and the coupling connector 26 can be easily attached or separated by hand, from the end portions 28, 30 of the body 20. After the arrangement of the respective components as illustrated in Figure 2, the knurled nut 24, which has the internal threads adapted to coincide with the first threaded end portion 28 of the body 20 is threaded in a manner released in the body 20 in a separate relation to the radial flange 32. While maintaining this respective position of the components, the assembly is inserted into the Anura with the flat surfaces 44 of the body aligned with the sides of the slot 42, and moved, by sliding, to a position in which the body 20 makes contact with the end of the slot 42. The knurled nut 24 in this manner is positioned adjacent the defined inner surface of the side panel 14 and the radial flange 32 is positioned adjacent the defined external surface 36 of the side panel 14. The knurled nut 24 is then hand-tightened manually, at the first end portion 28 of the body 20 until it is in contact with the internal surface of the side panel 14. In this way, when tightened, the knurled nut 24 is kept in electrical contact, hermetically connected, derived with the inner surface of the side panel 14, and the radial flange 32 of the body 290 is maintained in electrical contact, tightly connected, derived with the external surface 36 of the side panel 14. The installed position of the body 20 and the nut The knurled cavity 24 of the electrical connection assembly 22 on the side panel 14 is illustrated in Figure 3. It is important to note that the coupling connector 26 can be attached to the body 20, as illustrated in Figure 4, before or after assembly of the body 20 in the side panel 14. To complete the assembly of the box 12, the front cover 16 is attached on the open end of the box 12 and on the side panel 14 as shown in Figure 5, after installation of the removable ground connection embodying the present invention, the pair of connected cables 10, 10 'may, if desired, be removed from the side panel without disconnection. If, for any reason, ie inspection, repair or routine maintenance, it is necessary to have access to a component housed inside the box 12, the front cover 16 can be removed and the knurled nut 24 manually welded as illustrated in FIG. Figure 6. The connected pair of cables 10, 10 'can then easily be separated from the side panel 14 by sliding the body 20 along the slot 42 to a separate position from the side panel 14 without disturbing the electrical connection between the internal cable 10. and the external cable 10 '. Once the side panel 14 is cleared, the pair of cables 10, 10 'can be relocated in a position where it does not obstruct or otherwise prevent or hide access to the components housed inside the box 12. Thus, it can be seen that the connection assembly incorporating the present invention provides a removable cable ground connection that is effective in greatly reducing the emissions of the cables exiting from a base station, and can still be easily moved to allow access to the components in the base station without disconnecting the cable pairs. Although the use of ferrites placed on cables is a method to reduce emissions without requiring that the cables be attached to the structure of the box and thus not have to be disconnected to remove them, these cables treated with ferrite often do not adequately reduce electromagnetic emissions. The grounded, conventional bulkhead connections and the cables with protective cover adequately reduce emissions, but the coupling cables must be disconnected to provide access to the components in the box. The grounding of the removable cable in service incorporating the present invention establishes ground contact between the box 12 and the cable pair 10, 10 'by the use of the body 20 which is electrically connected to the ground connection of the internal cable 10. ' The body 20"is attached to the grounded box 12 by a manually removable nut 24 on the side of the box 12 opposite to which the external coupling and sprue wire is connected.Thus, the mounting nut 24 can be Released and tightened without disturbing the external cable connection Once the knurled nut 24 is loosened, the ground connection for the case 12 is lost, but since the connection with the coupling connector 26 is not disturbed, the connection between the internal cable 10 and the external cable 10 'remain.This feature not only allows movement of the cable pair 10, 10' to provide unobstructed access to the components housed within the box 12, but also allows the electrical components of the If desired, a temporary connection to ground can be provided by means of bridge clamps joined between the body 20 and the box 12. When grounding the internal cable 10 at its point of output from the box 12, that is, the point at which the external cable 10 'is coupled with the internal cable 10, most of the electromagnetic emissions conducted by the internal cable 10 inside the box 12 are not carried out of the box 12. Also, since the body 20 is mounted in an open-ended slot 42 and is not inserted through the hole, the body 20 can be displaced laterally outwardly of the slot 42 in the box 12 once the nut 24 is loosened, without disturbing the connection with the external coupling connector 26. Although the present invention is described in terms of a preferred exemplary embodiment, with illustrative, specific key constructions and connector arrangements, those skilled in the art will recognize what changes in these constructions and arrangements can be made without departing from the spirit of the invention. For example, the pair of internal and external cables 10, 10 'may contain one or more signal conductors and may also have a ground wire which is electrically connected to the body mounted on the panel 20. Also, if desired, the mounting slot 42 can be formed in the front cover 16, with an orthogonal portion of the side panel 14 providing partial coverage over the slot 42. These changes are proposed to fall within the scope of the following claims. Other aspects, features and advantages of the present invention can be obtained from a study of this description and the drawings, together with the appended claims.

Claims (7)

1. A ground connection for a cable having a grounding member consists of: a first grounded panel forming a wall surface and a second panel that can be placed in a relationship at least partially superimposed with a predefined portion of the first panel, the first panel having defined internal and external flat surfaces, at least one edge extending between the flat surfaces that are exposed in response to the separation of the second panel and a slot having a predetermined width extending inwardly from the end to a position separated from the shore; and an electrical connector assembly that includes a body electrically connectable to the cable grounding member and adapted to be received within the slot in a position spaced from the edge of the first panel, the body having a first externally threaded end portion, a second end portion, and a radial flange extending outwardly from the body at a position between the first and second end portions, an internally threaded member that can be attached to the first end portion of the body and arranged to secure the body to the first panel in response to tightening of the internally threaded member on the first externally threaded end portion of the body, whereby the internally threaded member is maintained in tightly connected electrical contact, derived with the defined inner surface of the first panel, and the radial flange of the body is maintained in electrical contact, tightly spliced, derived with the defined external surface of the first panel.

2. A cable ground connection, as set forth in claim 1, wherein the first end portion of the body of the connection assembly has a generally cylindrical external shape except for a pair of parallel flat surfaces formed on the diametrically opposite sides of the cable. the cylindrical shape, and the predetermined width of the groove is smaller than the diameter of the generally cylindrical external shape of the body, the body being mountable on the first panel in response to the alignment of the opposite flat surfaces of the body with the groove, placing the radial flange adjacent the defined outer surface of the first panel, sliding the body to the position separated from the edge of the first panel, and pressing the internally threaded member into the first end portion of the body.

3. The cable ground connection, as set forth in claim 1, wherein the internally threaded member that can be attached to the first end portion of the body of the connection assembly is a "knurled nut adapted for manual installation on and the separation of the first end portion of the body without the aid of tools

4. The cable ground connection, as set forth in claim 1, wherein the electrical connection assembly includes a coupling connector adapted for coupling with the second portion end of the body

5. The ground connection of the cable, as set forth in claim 4, wherein the coupling connector adapted for coupling with the second end portion of the body of the connection assembly has a knurled external surface that helps manual installation on and separation of the second end portion of the body

6. The cable ground connection, as set forth in n claim 1, wherein the first end portion of the body of the connection assembly is adapted for connection to a coaxial cable having a braided cover by means of which the braided cover is in direct electrical communication with the body of the mounting Connection.

7. The ground connection of the cable, as set forth in claim 1, wherein the first panel is a side wall of a box for a mobile telephone system base station, and the second panel is a front cover for the box. SUMMARY OF THE INVENTION The body of a connection assembly is attached to the ground connection of a cable placed internally inside a box. The connecting body has a radial flange placed on the outer surface of the box and a threaded nut on a portion of the connector extending internally to the box, is used to secure the body of the connector, whereby a ground connection is established between the body of the connector and the box. The panel of the box in which the body is mounted is grounded. A mating connector may be attached to a portion of the body of the connector extending outwardly from the case. In normal operation, the slot in which the connection assembly is installed is covered. However, when it is necessary to have access to the interior of the box, the connector and the attached cables can be removed from the panel of the box by separating the cover, welding the nut placed on the inner end of the connector body and sliding the assembled connector and the pair of wires out from the slot. The connector, and the pair of cables attached to it, can be moved out without separation or disconnection. This invention solves the problem of requiring the disconnection of pairs of coupling • cables when performing maintenance, inspection, repair or other activity on the enclosed electronic components such as the base station 'of a mobile telephone system.