FIELD OF THE INVENTION
The present invention relates generally to the electrical connectors, and more particularly to connectors for receiving a ground cable or wire.
BACKGROUND OF THE INVENTION
It is important in providing ground connections to housings of electrical devices, between devices, and to other typical electrical installations, that the connectors used permit easy, efficient, and reliable connection to ground wire or cable terminations. Known connectors are prone to damage the bared ends of ground wires or cables, and as such require care in use. There is a need in the art for connectors that permit rapid and easy connection to ground wires or cables, while substantially avoiding damage to the terminating bared end of the wire or cables.
SUMMARY OF THE INVENTION
In one embodiment of the invention, a ground block connector is provided in an electrically conductive protrusion of an electrical device housing. The protrusion includes means for captively retaining a screw adapted for moving a compressive ground contact downward in an open slot, for compressively retaining and electrically connecting to a bared wire end of a ground wire or cable inserted between the bottom of the slot and the bottom of the ground contact.
BRIEF DESCRIPTION OF THE FIGURES
Various embodiments of the present invention are described in detail below with reference to the figures in which like items are identified by the same reference designation, wherein:
FIGS. 1 through 3 are pictorial diagrams of an embodiment of the invention, all shown in association with a portion of a housing of an electrical device;
FIG. 4 is a pictorial exploded assembly diagram of an embodiment of the invention;
FIG. 5 is a partial pictorial view showing details of slot projections for an embodiment of the invention;
FIGS. 6A through 6D show top plan, bottom plan, right side elevational, and front elevational views of a retaining clip for an embodiment of the invention, the left side elevational view being a mirror image of the right side elevational view;
FIG. 7 is a pictorial diagram of an embodiment of the invention as used in association with an electrical digital splitter, for example;
FIGS. 8 through 10 are pictorial diagrams of a preferred embodiment of the invention, all shown in association with a portion of a housing of an electrical device; and
FIGS. 11A through 11E are a perspective view, a top plan view, a front elevational view, a right side elevational view, and a back elevational view, respectively, of a combined ground block and clip for a preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a ground block connection that can be used with cable television devices, and other electrical devices, particularly those associated with housings for enclosing various electrical components. However, the invention is not meant to be so limited, and can in certain embodiments be used to provide a stand alone ground block connector, for example. With reference to FIGS. 1 through 4, in one embodiment of the invention, the ground block connector 1 is retained in a sidewall protrusion 3 from the main housing 6 of a cable television device 5, such as an amplifier or splitter, or from housings for other electrical devices, for example.
The ground connector block 1 is formed in an electrically conductive protrusion 3 from a housing 6 of an electrical device 5, in this example. More specifically as shown in FIG. 1, the ground connection connector block 1 includes a compression bolt or screw 7 that is rotated in one direction for moving a compression block or ground contact 9 downward in a slot 11, for compressing a bottom portion 10 of contact 9 against an electrical conductive wire (not shown), and a bottom portion 12 of slot 11, for securing the wire therein for grounding. In FIG. 1, the ground contact 9 is shown in an open position for permitting a wire end to be inserted in the open portion of slot 11. FIG. 2 shows the screw 7 having been rotated in the appropriate direction for moving the ground contact 9 downward in the slot 11, in this case for retaining the bared end of ground wire 2. As shown in FIGS. 3, 4, and 5, looking toward the back of the open slot 11, the slot is configured to be wider in its upper half portion 14 than its lower half portion 16, in order to permit the electrical contact 9 (see FIG. 4) to initially be inserted from the rear into upper portion 14 of the slot 11 above projections 4, after partially screwing a screw 7 into the threaded hole 13 in the top of the protrusion 3, whereby the U-shaped opening 15 on the top of the electrical contact 9 is pushed onto the unthreaded portion 17 of the screw 7, with the lowermost threads 20 of screw 7 being retained in the lower slot 22 of contact 9. As further shown, the screw 7 is then screwed in further to hold the electrical ground contact 9 captive in the lower portion 16 of the housing slot 11. The means for holding the contact 9 captive include the screw 7 preventing the contact 9 movement out of the front of slot 11, and two narrow projections or buttresses 4 formed in the opposing sides of the lower portion 16 of slot 11 to prevent removal of contact 9 from the back or rear of slot whenever any portion of contact 9 is positioned below the level of projections 4 (see FIGS. 4 and 5). The uppermost screw threads 19 are then utilized in conjunction with the mating threads in the central hole 13 at the top of the protrusion 3 for moving the electrical contact 9 up for freeing a previously installed ground wire 2 (see FIG. 2), or down in the slot 11, as previously described, for holding a bared ground wire end 2 captive between the bottom 10 of the electrical contact 9 and bottom 12 of slot 11 to provide a ground connection (see FIGS. 1 and 2). Typically, the housing 6 consists of an electrically conductive material, and the bottom 12 of slot 11 and bottom 10 of contact 9 and/or the electrical connection between the screw threads 19 and the threaded hole 13 in the center of the protrusion 3, provide a low resistance path to ground for electrical current between the ground wire 2 and the housing 6. Appropriate electrically conductive materials are used for the housing 6, bolt or screw 7, and compression block or ground contact 9, in this example, and each can be made from a single piece of material.
In another embodiment of the invention, after the ground contact 9 has been installed in the slot 11 and mounted on screw 7, as previously described (see FIGS. 1 and 2), a retaining clip 8 is pushed wholly into the lower slot 22 of ground contact 9, until the top folded lip 29 of retaining clip 8 is within the unthreaded portion 17 of screw 7. With reference to FIGS. 6A-6D, the retaining clip 8 right and left side arms 25, 27, respectively, have extreme portions of their free ends 26, 28, respectively, being bent inward, as shown, to ease installation. Also, the arms 25 and 27 are bent slightly toward one another both to ease installation, and to provide a width therebetween that is narrower than the outside diameter of the unthreaded portion 17 of bolt or screw 7, to retain clip 8 thereon. In this manner clip 8 is prevented from falling out from screw 7. The widest portion of retaining clip 8 between arms 25 and 27, proximate the front face 30 thereof, is slightly wider than the width of the lower slot 22 of ground contact 9, to insure a tight frictional fit of retaining clip 8 within the lower slot 22. The retaining clip 8 prevents the ground contact 9, after installation in the slot 11, from falling out of the upper half 14 of slot 11, at times that screw 7 is rotated to retaining clip 8 into that position in slot 11. The retaining clip 8 is made from any suitable metal or plastic material, and can be made from a single piece of material.
A preferred embodiment of the invention is shown in FIG. 8, and includes a combined ground block and clip 32. The clip 32 includes opposing resilient arms 34 and 36 extending from a uppermost portion of a back wall 38. The clip also includes a bottom portion 40 extending from the bottommost portion of the back wall 38 to a narrow front lip 42. The bottom portion 40 is spaced from the resilient arms 34 and 36 for an amount that is slightly greater than the length of the bottommost threaded portion 20 of screw 7. The combined ground block and clip 32 is installed on the screw 7, as shown in FIG. 8, by pushing it onto the screw 7 in a manner causing the resilient arms 34 and 36 to snap on and be firmly secured to the unthreaded portion 17 of screw 7, with a bottom of clip 32 proximate the bottom of screw 7, and the narrow front lip 42 adjacent and extending over the bottom portion of screw 7. Note that in this embodiment the slot 11 is narrower than in the previously described embodiments of the invention, and can be made slightly wider than the outside diameter of a threaded portions of the screw 7, but wide enough to accommodate the combined ground block and clip 32. In turn, the widest portion of the combined ground block and clip 32 can be made slightly narrower than the width of the slot 11. In FIG. 9, the combined ground block and clip 32 is shown installed on screw 7 and slot 11, along with being utilized to retain the bared end of a ground wire 2 between the bottom 40 of ground block/clip 32, and the bottom portion 12 of slot 11. Note that the operation of the combined ground block and clip 32 is substantially the same as for the previously described compression block or ground contact 9. Reference is further made to FIG. 10 looking toward the back of the slot 11 with the combined ground block and clip 32 installed on screw 7 within slot 11. Note that in this embodiment the slot 11 is not only narrower than in the previous embodiment, but also does not include a wider portion in its upper half as in the previous embodiment, thereby eliminating the projections 4 as used in the latter. Accordingly, in this embodiment of the invention, it is clearly simpler than the previously described embodiment, and completely eliminates any requirement for using a retaining clip, such as retaining a clip 8 as described above.
A perspective view of the combined ground block and clip 32 is shown in FIG. 11A. Note that in a top plan view thereof as shown in FIG. 11B, that the ends of the opposing resilient arms 34 and 36 initially bend inward, and then at their very ends bend outward, for facilitating the installation of ground block/clip 32 on to the screw 7. Note that the left side elevational view thereof is a mirror image of the right side elevational view shown in FIG. 11D. A back elevational view of the combined ground block and clip 32 is shown in FIG. 11E. The combined ground block and clip 32 can be made from a single piece of any suitable material, and of an appropriate thickness. For example, stainless steel having a thickness ranging from 0.25 to 0.4 millimeters can be used, and is acceptable for galvanic compatibility relative to the SCTE standard calling for use of a stainless steel screw 7 in this application, but the invention is not limited to this material or thickness.
Although various embodiments of the invention have been shown and described, they are not meant to be limiting. Those of skill in the art may recognize certain modifications to those embodiments, which modifications are meant to be covered by the spirit and scope of the appended claims. For example, the bolt or screw 7 can be installed through a threaded hole in the side of a housing protrusion 3 rather than in the top of the protrusion 3, with the slot 1 land electrical contact 9 or block/clip 32 being reoriented, accordingly. Also, as indicated, the present ground connector block 9 or block/clip 32 can be used on many different electrical device housings, such as that of FIG. 7 for a splitter, for example.
Patent Application
20060040531
