GB2121134A - Electronic connector box - Google Patents

Abstract

A watertight connector box has a removable plate (17) with projections extending through a gasket for engaging interior walls of the box to prevent lateral translation or rotation of the cover and conduit engaging means having a hollow threaded extension (22) with longitudinal slits (36) thereabout for clamping a conduit (21) upon tightening of a nut (37) thereon with tapered threads (39). In a second embodiment, a short hollow threaded cylinder (51) has a flange (52) with gasket (54) adapted to engage the interior of the box about an opening through which the cylinder extends with a split ring (58) having internal cerrations (66) and a tapered edge engaging a tapered outer end of the cylinder for tightening about a conduit (21) by a nut (57) about a conduit and having an internal shoulder engaging said split ring. <IMAGE>

Description

SPECIFICATION Electrical connector box Background of Invention Electrical wiring is commonly extended through conduits which may be joined to connector boxes, for example. Oftentimes in home construction, for example, connector boxes may be located where they may be subject to the elements and inasmuch as the box provides the only protection for electrical wires joined therein it is necessary that the box be truly watertight to prevent electrical shorts from moisture.

Summary of Invention The present invention provides a connector or junction box adapted to engage the ends of a plurality of electrical conduits in watertight relation. Electrical wires extending through these conduits may be joined in desired manner within the box hereof and to this end a removable cover plate is provided for access to substantially the entire interior of the box. Particular physical structure is herein provided to ensure positive gripping and locking of conduit ends and complete watertight integrity of the interior of the connector box.

The connector box may be formed as an integral unit including one or more hollow, externally threaded extensions for receiving conduits ends therein. A nut with tapered internal threads disposed about a conduit is threaded onto the extension to clamp the extension about a conduit end for locking the latter in place and a thin waterproof tape may be positioned between the threads to maximize the watertight relationship of the connection.

The connector box is also provided with "knock-out" plugs for providing opening through box walls where additional conduits are to be joined to the box. Such a joinder is herein accommodated by a hollow externally threaded cylinder having a flanged end adapted to bear upon a gasket against the interior of the box with the cylinder extending through a knock-out opening. The threaded cylinder has an inwardly tapered outer edge for engagement by a tapered edge of a split ring having internal serrations for gripping a conduit extending therethrough. A nut having internal threads and an internal shoulder about the outer end slidably engages a conduit and when threaded onto the threaded cylinder firmly locks the conduit in the extension by compressing the ring and compresses a gasket against the exterior of the box.A thin waterproof tape may be employed in the above-noted threaded connection.

The connector box is provided with a removable cover attached as by screws over an open side or top of the box and having internal projections disposed to engage internal walls about the open side or top of the box to prevent lateral movement of the cover. A waterproof gasket internally of the cover has openings for the internal cover projections and is clamped between the cover and a rim about the box opening for sealing the cover to the box.

Brief Description of Figures The present invention is illustrated in the accompanying drawings as to a preferred embodiment thereof wherein: Figure 1 is a perspective view of the exterior of a connector box in accordance with the present invention; Figure 2 is a vertical sectional view taken in the plane 2-2 of Figure 1; Figure 3 is an enlarged partial sectional view as indicated at 3 in Figure 2; Figure 4 is a longitudinal sectional view taken in the plane 4-4 of Figure 1; Figure 5 is an exploded view of cover, gasket and top of the connector box of Figure 1; Figure 6 is an exploded view of the front side connector of Figure 1; and Figure 7 is an exploded view of the right end connector of the connector box of Figure 1.

Description of Preferred Embodiment The improved watertight connector box of the present invention, as illustrated in the drawings, will be seen to include an integral metal or plastic housing 11 which may have a generally rectilinear configuration with sides walls 12--121, end walls 13--131, a bottom wall 14 and an open top 16.

The cover 1 7 is adapted to fit upon the open top 16, as further described below, to thus fully enclose the interior 18 of the housing.

The connector box of the present invention is adapted to receive a plurality of electrical conduits 21 in watertight relation thereto. These conduits are adapted to carry insulated electrical conductors which may be joined together in any desired manner within the connector box with these connections then being sealed therein by the cover 1 7. Access to the connections is readily provided through the open top 16 of the housing by removal of the cover 17.The connector box is normally provided with one or more integral, hollow, cylindrical projections 22 opening to the interior of the housing and in the illustrated embodiment there is shown a cylindrical extension from an end and a bottom of the housing.The interior opening of the extensions 22 are dimensioned to slidably receive a conduit 21, as indicated in Figure 2 and an interior shoulder about the inner end of the cylinder openings, as indicated at 23, serves to receive the inner end of the conduit in abutting relationship thereto. The exterior of the cylinder 22 is threaded, as indicated at 24, and the outer end of the cylinder has an inwardly tapering edge as indicated at 26.

Reference in this respect is also made to Figure 3.

A split ring 27 having tapered edges, as indicated, is disposed about the conduit 21 adjacent the outer end of the cylinder 22 and a nut 28 also disposed about the conduit is threaded upon the cylinder 22. This nut 28 has an internal shoulder 29 slidably engaging the conduit 21 with the interior of the nut opening tapering outwardly therefrom to the threaded portion of the nut, again as illustrated in Figures 2 and 3.

It will be seen that tightening of the nut 28 on the threaded cylinder 22 about the conduit 21 will cause the split ring to be forced against the tapered end of the cylinder 22. This will compress the ring 27 and the flared portion of the nut will also compress the ring 27 so that it will be tightened about the conduit 21 to lock the latter in place. There may also be provided a thin waterproof tape 31 disposed between the threads on the cylinder 22 and nut 28 which will then be crushed by the threaded engagement of these two elements so as to ensure a watertight connection at the threaded engagement.

In the illustrated embodiment of the present invention there are in fact provided two integral threaded cylindrical extensions and the one shown in the end 1 31 of the housing is also illustrated in exploded view in Figure 7.

Referring to Figures 4 and 7 in this respect it is noted that the cylindrical extension 22 with threads 24 about the exterior thereof is provided with a plurality of longitudinal slits 36 therethrough and spaced equally thereabout. This cylinder 22 is adapted to receive the conduit 21 in slidable relationship therein for abutting against the shoulder or internal flange 23 in the same manner as described above; however, the nut 37 adapted to cooperate therewith is slightly different from the one described above. The nut 37 has a shoulder or internal flange 38 about the outer end thereof adapted to slidably engage the exterior of a conduit 21; however, the internal threads 39 of the nut taper slightly outwardly from this nut shoulder towards the inner end of the nut.This is illustrated in Figure 4: however, the taper is quite small and is thus emphasized herein as it might not be noticed in viewing the drawing. With the conduit inserted in the cylinder 22 the nut is then tightened on the cylinder and as it is threaded thereon it will compress the cylinder or actually the cylindrical sections between the longitudinal slots 36 therein. This will cause the cylinder to firmly grip the conduit and, consequently, to lock the conduit in place. It is also desirable in this instance to apply a thin waterproof tape about the external threads 24 of the cylinder 22 so that threading of the nut onto the cylinder will compress or crush the tape to ensure a watertight joinder of nut and cylinder.

The connector box of the present invention may require the connection of conduits to various sides, bottoms or ends of the unit and thus in addition to the integral hollow cylindrical projections 22 described above there is also provided circular knock-out portions 41 in the housing 11 which may be physically removed by striking same a sharp blow. The knock-out 41 may be provided as a portion of the wall with reduced diameter or weakened periphery so that it may be relatively readily removed but which does retain the watertight integrity of the interior 1 8 of the housing 11.

The drawings hereof illustrate one of these knock-outs 41 as having been removed in the side wall 12 of the housing and reference in this respect is made to Figures 4 and 6 illustrating provisions hereof for engagement with an electrical conduit 21 at such location. An externally threaded cylinder 51 is provided with a flange 52 about the inner end thereof and a shoulder 53 internally of the hollow cylinder for abutting the end of a conduit 21 slidably fitting into the cylinder. This threaded cylinder 51 is adapted to extend through an opening 411 in a wall 12 of the housing produced by removal of the knock-out element 41 and a gasket 54 is disposed about the cylinder internally of the housing for compression between the rear cylinder flange 52 and the housing wall 12.Exteriorly of the wall 1 2 there is provided a waterproof gasket 56 adapted to be disposed about the threaded cylinder 51 and a nut 57 having internal threads and a shoulder slidably engaging a conduit 21 is adapted to be threaded upon the cylinder 51. Between the nut 57 and the cylinder 51 there is provided about the conduit 21 a split ring 58 having tapered edges, as indicated, and formed of a resilient deformable material such as metal or plastic.The outer end of the cylinder 51 has the edge thereof tapered radially inward, as indicated at 61 and the internal shoulder on the nut 57 is tapered radially outward toward the housing, as described above in connection with the illustration of Figures 2 or 3, so that tightening of the nut 57 on the threads of the cylinder 51 will force the split ring 58 against the tapered edge or rim of the cylinder 51 and will thus compress the split ring again in the manner illustrated in Figures 2 and 3. There are provided longitudinal serrations 66 on the internal surface of the split ring 58 for gripping the conduit 21 as the split ring is compressed thereabout.This provided a firm joinder of conduit to connector box; Should it be deemed necessary the threaded engagement of the cylinder 51 and nut 57 may be additionally waterproofed by the provision of a thin waterproof tape as employed in other connections of the present invention. Such a tape may be provided as a "thread seal tape" in the form of a thin teflon material, preferably having an adhesive on one surface so as to be readily attached in position upon the external threads of the cylinder 51 ,for example, whereby threading the nut thereon will cause the nut to rise over the tape and to compress same between the threads of the nut and cylinder.

The connection described immediately above will be seen to provide for a substantially permanent and waterproof connection of conduit and housing so that electrical wires extending through the conduit may also extend into the interior 1 8 of the housing for desired connections therein.

The closure of the housing 11 of the present invention is accomplished as briefly noted above by a cover 17 adapted to fit over an open top 1 6 of the housing. This cover is provided as a single, integral generally planar unit adapted to rest upon a rim 71 about the open top 1 6 of the housing.

The cover is provided with internal or lower projections 72 which are positioned to engage the side walls of the housing when the cover is placed in closing relationship to the open top thereof for preventing any lateral movement of the cover with respect to the housing. There is also provided a waterproof gasket 73 having openings therethrough accommodating passage of the projection 72 of the cover and disposed in contact with the under side of the cover 1 7. Attachment of the cover to the housing may be accomplished by a pair of screws 76 which are adapted to extend through openings 77 in the cover and into threaded engagement with tapped bores 78 in end extensions of the rim 71 about the open top of the housing.In this respect it is noted that the openings 77 in the cover 1 7 are somewhat longitudinally elongated but have a width slightly less than the outside diameter of the threads on the screw 76. This allows forcing of the screw 76 through the opening 77 so that the screws are retained in the cover but are not threaded therein.

Instead, the screws are threaded only into the tapped bores 78 in the top of the housing rim 71.

This is advantageous in machine assembly of the present invention.

The present invention has been described above with respect to a single preferred embodiment thereof and incorporating a number of improvements over the prior art. The housing 11 has been noted to include integral hollow, externally threaded extensions whereat electrical conduits may be secured to the housing for extension of electrical wiring into the interior of the housing. The housing of the connector box hereof is also noted to include knock-out portions whereat particularly configures and highly advantageous attachment of electrical conduits may be accomplished in accordance with the present invention, as illustrated, for example, in Figure 6. Furthermore, the present invention provides a truly watertight engagement of housing and conduits as well as a truly watertight closure of the cover of the housing which is, however, removable for access to the interior thereof in order to complete electrical connections or repair same. There is thus provided hereby a highly practical electrical connection box for engagement with electrical conduits and adapted to contain and fully protect electrical connections between wiring within such conduits.

Although the present invention has been described above with respect to particular preferred embodiments thereof it is not intended to limit the invention to particular terms of description or precise details of illustration for it will be apparent to those skilled in the art that numerous modifications and variations may be made within the spirit and scope of the present invention.

Claims (7)

1. An improved connector box including an integral watertight housing with an open top with a removable cover therefor comprising at least one hollow cylindrical projection from said housing defining an opening therein with a shoulder thereabout within the projection, said projection having external threads thereabout and thin longitudinal slots therethrough for threaded engagement with a nut having tapered internal threads and adapted for disposition about a conduit inserted in said projection against said shoulder for tightening said projection about said conduit to lock said conduit in place.

2. The connector box of Claim 1 further defined by said housing having at least one opening through a wall thereof, a hollow externally threaded cylinder having a flange about an inner end thereof extending through said housing opening with a gasket between said flange and the interior of said housing about said opening and an inwardly tapered edge about the outer end thereof, a split ring having a tapered edge facing said cylinder and adapted to fit about a conduit extending into said cylinder in slidable rotation thereto, and an internally threaded nut having an internal shoulder about an outer end thereof and adapted to slidably engage said conduit for threaded engagement with said cylinder for forcing said ring against the tapered edge of said cylinder to lock said conduit in place.

3. The connector box of Claim 2 further defined by said split ring having both edges tapered and said nut having the internal shoulder thereof inclined forwardly from the outer end of said nut for also compressing said ring about a conduit extending therethrough.

4. The connector box of Claim 2 further defined by a thin waterproof tape disposed about the threads on said cylinder beneath the threads on said nut and a gasket about said cylinder and compressed against the exterior of said housing by said nut.

5. The connector box of Claim 1 further defined by said housing having a flat rim about said opening top, said cover extending over said rim with means for securing the cover to the rim and said cover having interior projections disposed to engage the interior sides of said open top in position to prevent lateral movement of said cover on said housing with the cover in place, a waterproof gasket disposed on the interior side of said cover with openings for said projections to extend therethrough and adapted for clamping between said cover and housing rim to ensure watertight closure of said housing with said cover secured in closing relation to the open top thereof.

6. The connector box of Claim 3 further defined by said ring having longitudinal serrations on the inner surface thereof for positive gripping of a conduit as said ring is compressed thereabout.

7. A connector box substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.