US3621113A

US3621113A - Connector and conduit and method of manufacture

Info

Publication number: US3621113A
Application number: US872861A
Authority: US
Inventors: Kenneth Westby
Original assignee: Thomas Industries Inc
Current assignee: Thomas Industries Inc
Priority date: 1969-10-31
Filing date: 1969-10-31
Publication date: 1971-11-16
Anticipated expiration: 1988-11-16

Abstract

A tubular member adapted to serve as a conduit for electrical wiring and also adapted to serve as a structural element for securing together other structural elements, such as walls of a housing, or the like.

Description

United States Patent 72] lnventor Kenneth Westby [56] References Cited Fm UNITED STATES PATENTS [21] Appl. No. 872,861

- 142,165 8/1873 Kmtz 248/344 [22} Filed Oct. 31, 1969 1,044,283 11/1912 Stanger.... 72/325 [45] Patented Nov. 16, 1971 1,391,612 9/1921 Butler 248/343 [73] Assrgnee Thomas Industries Inc.

Fort Atkinson Wis 1,407.527 2/1922 Goldrlch 248/344 1,408,128 2/1922 Neahr 211/26 1,572,728 2/1926 Kestell 248/344 X 3,467.938 9/1969 Jahr .7 174/51 X [54] CONNECTOR AND CONDUIT AND METHOD 0F MANUFACTURE Primary Exammer Lewis H. Myers 22 Chin's, 8 Drawing Fina Assistant Examiner-D. A. Tone Attorney-Johnson, Dienner, Emrich, Verbeck & Wagner [52] U.S. CI 174/51, 174/61, 248/344, 240/78 F, 72/325 [51 Int. Cl H02g 3/20 ABSTRACT: A tubular member adapted to serve as a conduit [50] Field of Search 174/61, 51; for electrical wiring and also adapted to serve as a structural 21 1/26; 248/342, 343, 344; 240/78 G, 78 LD, 78 element for securing together other structural elements. such R; 72/325 as walls ofa housing, or the like.

PATENTEDN Y 1 ml 8.621.113

sum 2 [1F 3 frzuerzfar nemez W'esiy CONNECTOR AND CONDUIT AND METHOD OF MANUFACTURE BACKGROUND OF THE INVENTION This invention arose through the need for improved and less expensive structures for lighting fixtures and it will be illustrated and described in connection with a lighting fixture. However the invention has wider utility as will be indicated below.

The invention has particular utility in connection with lighting fixtures of the chandelier-type in which a plurality of lighting branches are extended outwardly from a suspended center structure. However, the invention may also be employed where a single lighting branch is used or where the fixture is mounted against the wall.

Commonly, the center structure is suspended from a ceiling, beneath an electric supply outlet on the ceiling, by means of a decorative chain or other supporting structure. In some instances, the center structure may be suspended from a wall bracket or the like.

In a typical form of electric lighting fixture of the chandelier type, the center structure comprises a decorative spindle having upper and lower body portions, upper and lower externally threaded tubular members (often referred to as nipples); a U-shaped bracket (often referred to as a hickey"), and a wire-splice housing supporting a plurality of outwardly extended lighting branches and being disposed between the upper and lower body portions. A top wall of the wire-splice housing forms part of a cover which is separable from the remainder of the wire-splice housing. The latter includes a bottom wall. The upper and lower spindle body portions are provided with axial bores so as to fit over the respective tubular members.

The lower end of the upper tubular member, on which a lock nut is threaded, extends through an opening in the top wall of the wire-splice housing, and through a lockwasher, and is threaded into a suitably threaded opening in one leg of the U-shaped member. The upper end of the upper tubular member extends above the upper spindle body portion for connection with an internally threaded cap which forms part of means from which the center structure is to be suspended. First and second wires, to which connections for the circuits of the lighting branches are made, and a third wire, by which the exposed structure of the fixture is independently grounded and isolated from the line, extend through the upper tubular member into the wire-splice housing. Connections to the first and second wires are made within the wire-splice housing. The third wire is exposed and is twisted around the lock washer for electrical connection to the wire-splice housing and other exposed structure of the fixture. When the lock nut is tightened against the top wall of the wire-splice housing and the threaded cap is tightened onto the upper end of the upper tubular member, the upper spindle body portion is drawn against the top wall of the wire-splice housing so as to produce an integral assembly of the upper tubular member, the upper spindle body portion, the top wall of the wire-splice housing, and the U-shaped bracket.

The upper end of the lower tubular member extends through an opening in the bottom wall of the wire-splice housing and is threaded into a suitably threaded opening in the other leg of the U-shaped bracket. The lower end of the lower tubular member extends below the lower spindle body portion for connection with an internally threaded decorative knob. When the decorative knob is tightened onto the lower end of the lower tubular member, the lower spindle body portion is drawn against the bottom wall of the wire-splice housing so as to produce an integral assembly of the lower tubular member, the lower spindle body portion, the bottom wall of the wiresplice housing, and the U-shaped bracket.

Conventionally, the wire-splice housing is approximately one inch or less in height and approximately 4 inches or less in diameter, and a considerable portion of the space within the wire-splice housing is occupied by the U-shaped bracket. Consequently, only a limited space is available for making connections for the lighting branches. This is particularly disadvantageous if the fixture has six, eight, or even more lighting branches, as is common. Furthermore, assembly and disassembly of the center structure for installation and repair of the fixture is complicated by reason of the necessity to employ the U-shaped bracket within the wire-splice housing to associate the upper and lower tubular members.

There is a need for an electric light fixture of the chandelier type, in which the available space for connections to the lighting branches has been enlarged, and in which assembly and disassembly of the center structure have been simplified.

SUMMARY OF THE INVENTION Accordingly it is one object of this invention to provide a tubular member adapted to serve as an improved conduit for electrical wiring. It is a further object to provide such a conduit which is also adapted to serve as a structural element for securing members together.

More particularly it is an object to provide an electric lighting fixture of the chandelier type, in which the available space within a wire-splice housing for connections to the lighting branches has been enlarged.

It is another object of this invention to provide such an electric lighting fixture, in which assembly and disassembly of the center structure have been simplified.

It is yet another object of the invention to reduce the cost of production of the fixture by simplification of the parts and reduction in the amount of labor needed in its assembly. Further savings are achieved by reduction in the number of parts to be stocked.

In accordance with the teachings of this invention, the preceding objects may be attained in an electric lighting fixture of the chandelier type having a center structure in which the aforementioned upper and lower tubular members and the aforementioned U-shaped bracket have been eliminated and replaced by simplified structure comprising a single generally tubular member passing through the opening in the top wall of the wire-splice housing, a bead integral with the generally tubular member supporting the top wall of the wire-splice housing at the margin of the opening in its top wall and means for preventing twisting of the top wall of the wire-splice housing relative to the generally tubular member.

The generally tubular member extends downwardly through the wire-splice housing, through an opening in its bottom wall, and has a lateral opening of novel construction permitting wires to pass from the generally tubular member into the wiresplice housing. Preferably, guide means are provided for guiding wires outwardly from the generally tubular member through the lateral opening into the wire-splice housing. Preferably, the generally tubular member is lanced in that portion which is within the wire-splice housing and the lanced portion is formed in such a manner as to provide the desired lateral opening in the generally tubular member and also to provide integral guide means for guiding wires outwardly from the generally tubular member through the lateral opening into the wire-splice housing.

The means for preventing twisting of the top wall of the wire-splice housing relative to the generally tubular member may comprise an integral tab on the generally tubular member, above the bead, fitting into a notch formed in the margin of the opening in the top wall of the wire-splice housing. A portion of the bead may be displaced upwardly to form the tab. A grounding washer may be provided between the bead and the margin of the opening in the top wall of the wiresplice housing.

These and other objects, features and advantages of this invention will be evident from the following description, with the aid of the attached drawings, of a presently preferred embodiment of this invention.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is an elevational view, with portions broken away, of an electric lighting fixture of the chandelier type embodying the principles ofthis invention;

FIG. 2 is an elevational view, on an enlarged scale and partly broken away, showing the center structure of the fixture;

FIGS. 3 and 4 are elevational views showing the generally tubular member with its bead and tab, FIG. 4 being taken substantially from the right side of FIG. 3;

FIG. 5 is an enlarged sectional view of the generally tubular member, but omitting the tab, taken approximately along the line 5-5 of FIG. 3, looking in the direction ofthe arrows;

FIG. 6 is a top plan view showing the upper portion of the wire-splice housing of the fixture, taken substantially along line 66 of FIG. 2;

FIG. 7 is a fragmentary view of the tubular member showing an alternative way of grounding the fixture;

FIG. 8 is a diagrammatic view of equipment used in the construction of a tubular member in accordance with this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT X FIG. I shows an electric lighting fixture, indicated generally at 10, incorporating the presently preferred embodiment of this invention. The electric lighting fixture 10, which is of the chandelier type, comprises a center structure, indicated generally at 12, and a plurality of wire-carrying lighting branches 14 extending outwardly from the center structure 12. In the embodiment shown, the center structure 12 is designed to be suspended from a ceiling, indicated at 13, beneath an electrical supply outlet (not shown) in the ceiling, by means ofa decorative chain 16.

The center structure 12 comprises a decorative spindle body, indicated generally at 18, which has upper and lower body portions, and 22 respectively, and a wire-splice housing 24 which is disposed between the upper spindle body portion 20 and the lower spindle body portion 22. The wire-splice housing 24 comprises a base 26 (FIG. 2), which has a generally circular bottom wall 28 and an upturned peripheral flange 30, and a cover 32, which has a generally circular top wall 34 and a generally cylindrical sidewall 36. When the wiresplice housing 24 is assembled, the sidewall 36 of the cover 32 fits snugly within the upturned peripheral flange of the base 26.

Each of the lighting branches 14 comprises a tubular supporting arm 38 and a socket cup or bobeche 40. It will be understood that the tubular arms could be straight or could take other shapes. One end 42 of the tubular supporting arm 38 is radially outwardly extended from the side wall 36 of the cover 32 of the wire-splice housing 24 and is rigidly supported on the side wall 36 by means of a conventional bead 44 and swagged end 45 engaging the opposite sides of the margin of an opening 46 in the sidewall 36 (FIG. 2). Other conventional means of securing the arms 38 to the housing could be used. The other end 48 of the tubular supporting arm 38 rigidly supports the socket cup 40 in an upright position. The tubular supporting arm 38 communicates with the interior of the wire-splice housing 24 and

wires

50 and 52 for the circuit of the lamp socket in socket cup 40 extend into the wire-splice housing 24 from the lamp socket through the tubular supporting arm 38.

An integral assembly is produced of the two portions of the spindle body 18 and the wire-splice housing 24, by means ofa single elongated upright generally tubular member 60, on which is provided an integral bead 62. An upper portion 64 of the generally tubular member 60 passes through an opening 66 (FIG. 6) in the top wall 34 of the cover 32 of the wiresplice housing 24 and through an elongated bore 68 in the upper body portion 20 of the spindle body 18. As shown in FIG. 2, a grounding washer 70 is disposed between the top wall 34 of the cover 32 of the wire-splice housing 24 and the bead 62 for purposes to be described hereinafter. The upper end 72 of the generally tubular member 60 is externally threaded for connection with an internally threaded cap 74,

which is attached to the aforementioned chain 16 by means of an integral link 76. The threaded cap 74 has an opening 78 to permit wires to be fed from the outlet (not shown) in the ceiling to the generally tubular member 60. The wires may be entwined with the chain 16, in conventional manner. In FIG. I, the wires are omitted for clarity of illustration. A lower portion 80 of the generally tubular member 60 passes through an opening 82 in the bottom wall 28 of the base 26 of the wiresplice housing 24 and through an elongated bore 84 in the lower body portion 22 of the spindle 18. The lower end 86 of the generally tubular member 60 is externally threaded for connection with an internally threaded knob 88. When the knob 88 and cap 74 are appropriately threaded on to the ends ofthe tubular member 60 all of the intervening parts of the fixture are drawn together into a rigid assembly.

The generally tubular member 60 has means for providing communication between its interior and the interior of the housing 24. This is in the form of a lateral opening 90 permitting wires to pass from the generally tubular member 60 into the wire-splice housing. THe generally tubular member 60 is lanced adjacent the bead 62, as indicated in FIGS. 3 and 4, and the wall of the tubular member adjacent the bead is pressed into the tubular member in such a manner as to form the lateral opening 90 and also provide integral guide means 94 for guiding wires outwardly from the generally tubular member 60 into the wire-splice housing 24. Guide means 94 is concave upwardly and the cut end lies closely adjacent or in contact with the inner wall surface of the tubular member. As shown in FIG. 5, preferably the cut in the tube extends around the periphery of the tubular member about l40l 80, and the cut, or lance extends through a portion of the bead 62, as at 63, and the depressed free end of the integral guide means 94 lies at the inner annular groove 65 of bead.

A pair of insulated wires 96 and 98, respectively, (FIG. 2) extend through the generally tubular member 60 into the wiresplice housing 24. The wire 96 is electrically connected to the wires 50 (only one shown for clarity of illustration) for the respective lighting branches 14, and, similarly, the wire 98 is electrically connected to the wires 52 (only one shown) for the respective lighting branches 14. Preferably, as shown, an exposed end portion (not numbered) of the wire 96 is twisted or spliced with exposed end portions (not numbered) of the wires 50 of the lighting branches l4 and the wires are secured together inside an insulative cap 104, and, similarly, an exposed end portion (not numbered) of the wire 98 is twisted or spliced with exposed end portions (not numbered) of the wires 52 of the lighting branches l4 and the wires are secured together inside an insulative cap 106. The wires 96 and 98 are arranged to supply electric power from the electrical outlet (not shown) to the lamp sockets 40 of the respective lighting branches 14. A grounding wire 108, which is not insulated, extends through the generally tubular member 60 into the wire splice housing 24 and, as shown in FIG. 2, is twisted around the grounding washer 70 which engages the cover 32 of the housing 24. FIG. 7 shows an alternative arrangement whereby the grounding washer 70 is eliminated and the wire 108 is held by a setscrew 110 threaded into a suitably threaded lateral opening 112 in the generally tubular member 60.

To prevent the electrical connections within the wire-splice housing 24 from being impaired, or the insulation on the wires from being cut, it is important that the top wall 34 ofthe cover 32 of the wire-splice housing 24 and the associated arms 38 be prevented from twisting relative to the generally tubular member 60. To this end, the fixture 10 further compresses means for preventing such twisting, in the form of an integral tab 116 (FIGS. 3 and 4) on the generally tubular member 60, above the bead 62. Conveniently, as shown, a portion of the bead 62 may grounding displaced upwardly to form the tab 116. The tab 116 fits into a notch 120 (FIG. 6) formed in the margin of the opening 66 in the top wall 34 of the cover 32 of the wire-splice housing 24. In the arrangement of FIG. 2, the grounding washer 70 has an internal diameter large enough, or is provided with an aligned marginal notch (not shown) to permit the tab 116 to pass through the grounding washer 70 and fit into the notch 120. In the arrangement of FIG. 7, the tab 116 is not required to pass through any grounding washer.

When the cap 74 is tightened onto the upper end 72 of the generally tubular member 60, the upper portion 20 of the spindle 18 is drawn tightly against the upper surface of the top wall 34 of the cover 32 of the wire-splice housing 24, and the bead 62 supports the top wall 34 about the margin of the opening 66. ln the arrangement of FIG. 2, the grounding washer 70 then is trapped between the bead 62 and the margin of the opening 66. In the arrangement of FIG. 7, the grounding washer 70 is eliminated. When the knob 88 is tightened onto the lower end 86 of the generally tubular member 60, the lower body portion 22 of the spindle 18 is drawn tightly against the lower surface of the bottom wall 28 of the base 26 of the wire-splice housing 24, and the base 26 is drawn tightly against the side wall 36 of the cover 32 of the wire-splice housing 24 with the sidewall 36 fitted snugly within the upturned flange 30 of the base 26.

The opening in the tubular member 60 and the formation of the integral guide means 94 may be provided in any of several ways. In FIG. 8 there is diagrammatically illustrated equipment which may be used for quickly and inexpensively producing the desired result. A supporting base 120 has a channel 122 of a length corresponding to that of the tubular member 60 and adapted to receive and support it at an angle to the horizontal with the already-formed bead 62 fitting in a mating groove 123 in the base. Supported above the base 120 for reciprocal movement in a vertical direction is a lancing and forming, or pressing, die 125 having a cutting edge 127 and a curved stamping portion 128 which produces the csncave shape of the guide means 94 after the lancing action is provided by the cutting edge. A single downward stroke lances the tubular member and forms the guide means 94, positioning it as shown in FIG. 5. With the supporting channel 122 inclined as shown, the vertically moving die 125 will cut through the upper portion of the bead 62. If the bead is not cut in this manner-for example, if the cut is parallel to one side ofthe beadan overhanging sharp edge ofthe bead or tubular member remains and may cut the insulation on the wires which are guided out of the opening 90 formed in the tubular member 60.

It should be evident, from the preceding description of the presently preferred embodiment of this invention, that the objects of this invention have been attained in an electric lighting fixture which is simplified in construction and may be readily assembled and disassembled. Furthermore, it should be understood that, while a preferred embodiment of our invention has been illustrated, modifications and changes coming within the scope of this invention may be suggested to those skilled in the art when they have our disclosure before them. Accordingly, the scope of this invention should be determined from the following claims.

What is claimed is:

1. In electrical conduit of the type comprising a generally tubular member in which electrical wiring is carried and having an opening through the wall of said member of a dimension to accommodate passage of said wiring, the improvement comprising guide means for the wiring leading from the interior of said tubular member and to said opening, together with a peripheral bead formed on the exterior of the tubular member, said guide means being formed from the wall of the tubular member.

2. The improvement of claim 1 wherein the guide means is formed by lancing the wall and depressing a portion of it adjacent the lanced area into the tubular member.

3. The improvement of claim 2 wherein the lanced area includes at least a portion of the bead.

4. The improvement of claim 2 wherein the depressed portion is formed with an exterior concave surface and has the cut end closely adjacent the inner wall surface of the tubular member.

5. The improvement of claim 1 wherein the bead includes a tab extending radially outwardly of the exterior wall of the tubular member.

6. The improvement of claim 5 wherein the tab is formed integrally with the bead as an offset thereof in a direction longitudinal of the tubular member.

7. The improvement of claim 1 wherein the guide means is formed by lancing the wall and depressing a portion of it adjacent the lanced area into the tubular member, the depressed portion is formed with an exterior concave surface and has the cut end closely adjacent the inner wall surface of the tubular member, and the lanced area includes at least a portion of the bead, together with a tab associated with said bead and extending radially outwardly of the exterior wall of the tubular member and offset from the bead in a direction longitudinal of the tubular member.

8. In an electric lighting fixture having a wire-splice housing which has a wall portion with an opening, said wall portion being connected with and opening into at least one tubular wire-carrying branch which extends outwardly of said wiresplice housing-the improvement comprising a tubular member which extends through said opening and serves as a wire conduit for electrical wiring, said tubular member having a support for supporting said wall portion, and means for preventing rotation between said tubular member and said wall portion.

9. The combination of claim 8 wherein the wire-splice housing has a pair of aligned openings through it, one of said openings being in the wall which is connected with at least one tubular wire-carrying branch, and wherein said tubular member extends through the aligned openings and thereby through said wire-splice housing and has a lateral opening which permits wire to pass from said tubular member into said housing.

10. The combination of claim 9 wherein the tubular member is lanced in that portion lying within the housing and the lanced portion is pressed into the tubular member to form a guide for wires which extend from the tubular member into the housing.

11. The combination of claim 10 wherein the support on the tubular member is an integral bead.

12. The combination of claim 11 wherein the means for preventing rotation between said tubular member and said wall comprises a tab formed from the bead fitting into a notch formed in the margin of the opening in said wall.

13. The combination of claim 12 wherein the tab is a displaced portion of said bead.

14. The combination of claim 11 together with a grounding washer disposed between said head and the margin of the opening in said wall.

15. The combination of claim 11 wherein said tubular member is ofa length to extend above and below said housing and is threaded at each end in spaced relation to said housing.

16. In an electric lighting fixture of the type having a wiresplice housing which includes a top wall having an opening therein and a side wall, a second opening in the bottom wall of said housing and aligned with said first opening, and a plurality of tubular wire carrying branches each of which extends outwardly from said side wall of said wire-splice housing, the improvement comprising an elongated generally tubular member passing through said aligned openings in said wire-splice housing, a bead integral with said generally tubular member supporting said top wall of said wire-splice housing at the margin of said opening in said top wall of said wire-splice housing, means establishing communication between the interior of the tubular member and the interior of said housing and means for preventing twisting of said housing relative to said generally tubular member.

17. The invention of claim 16 wherein the means establishing communication between the interiors of the tubular member and housing is an opening in the wall of the tubular member formed by lancing the wall of the tubular member in that portion lying within the housing and wherein the lanced portion is pressed into the tubular member to form a curved guide for wires which extend from the tubular member into the housing.

18. The invention of claim 16 wherein the means for preventing rotation between said tubular member and said wall comprises a tab formed from the bead and fitting into a notch formed in the margin ofthe opening in said top wall.

19. A method of forming an improved conduit for electrical wiring which comprises the steps of supporting a tubular member, forming a circumferential bead of double wall thickness integrally from the wall of the tubular member, then lancing the tubular member crosswise of its longitudinal axis and pressing a wall portion of said tubular member at one side of said lanced area into the tubular member to form an opening in the tubular member and a wire guide for guiding electrical wiring through the opening.

20. The method of claim 19 wherein the lancing step cuts the wall of the tubular member through an angle of approximately l40-l and wherein said wall portion is pressed into said tubular member until the cut edge is closely adjacent and substantially conforms to the shape of the inner surface of the tubular member generally opposite said lanced area.

21. The method of claim 20 wherein the lancing action cuts through a portion of the bead at an angle to remove at least a portion of one wall thickness of the bead.

22. The method of claim 19 together with the step of forming an integral tab associated with the bead and extending radially outwardly of the exterior wall of the tubular member by pressing a portion of the bead longitudinally of the axis of the tubular member.

Claims

8. In an electric lighting fixture having a wire-splice housing which has a wall portion with an opening, said wall portion being connected with and opening into at least one tubular wire-carrying branch which extends outwardly of said wire-splice housing,-the improvement comprising a tubular member which extends through said opening and serves as a wire conduit for electrical wiring, said tubular member having a support for supporting said wall portion, and means for preventing rotation between said tubular member and said wall portion.

14. The combinAtion of claim 11 together with a grounding washer disposed between said bead and the margin of the opening in said wall.

15. The combination of claim 11 wherein said tubular member is of a length to extend above and below said housing and is threaded at each end in spaced relation to said housing.

16. In an electric lighting fixture of the type having a wire-splice housing which includes a top wall having an opening therein and a side wall, a second opening in the bottom wall of said housing and aligned with said first opening, and a plurality of tubular wire carrying branches each of which extends outwardly from said side wall of said wire-splice housing, the improvement comprising an elongated generally tubular member passing through said aligned openings in said wire-splice housing, a bead integral with said generally tubular member supporting said top wall of said wire-splice housing at the margin of said opening in said top wall of said wire-splice housing, means establishing communication between the interior of the tubular member and the interior of said housing and means for preventing twisting of said housing relative to said generally tubular member.

18. The invention of claim 16 wherein the means for preventing rotation between said tubular member and said wall comprises a tab formed from the bead and fitting into a notch formed in the margin of the opening in said top wall.

20. The method of claim 19 wherein the lancing step cuts the wall of the tubular member through an angle of approximately 140*-180* and wherein said wall portion is pressed into said tubular member until the cut edge is closely adjacent and substantially conforms to the shape of the inner surface of the tubular member generally opposite said lanced area.