Track Light System

Abstract

This invention discloses the combination of an elongated trackway and a mounting device for removably connecting an electrical unit to the trackway. The trackway comprises an elongated channel member having a back wall and two side walls with a pair of corresponding in-turned flanges formed at the outer ends of the two side walls to present a lengthwise slot. An elongated insulative member is mounted within the channel member and includes a pair of spaced apart receptacles in alignment with the lengthwise slot. A pair of conductors extend through each receptacle lengthwise of the channel member. The mounting device is assembled in a hollow housing having an open end. A plug unit is inserted in the open end, and includes an insulative head member mounted within the open end and a pair of contact blades extending through the insulative head member outwardly of the open end in a spaced apart relation corresponding to the distance between the pair of receptacles. The mounting device further includes latching means extending forwardly of the housing's open end for engaging the in-turned flanges of the channel member upon the contact blades being inserted into the pair of receptacles to hold the mounting device in place, and includes releasing means which selectively disengages the latching means to permit the removal of the mounting device from the trackway.

Description

BACKGROUND OF THE INVENTION

This invention relates to the combination of an elongated trackway, which is a part of a power distribution system, and a mounting device capable of connecting an electrical unit, such as a lighting fixture, to the elongated trackway.

There are a number of prior art systems that provide an elongated track member and a mounting device for connecting an electrical fixture to the trackway. These prior art systems have a large number of interrelated parts which are relatively expensive to manufacture and which are rather cumbersome to use in fastening the mounting device to the trackway. By contrast, this invention provides a rather simple but unique design for connecting a mounting device to a trackway which cooperate together in a manner to permit the mounting device to be quickly connected or disconnected. Because this invention uses a relatively small number of cooperating parts, it is inexpensive to manufacture and substantially maintenance-free.

SUMMARY OF THE INVENTION

An electrical power distribution track system comprising an elongated trackway and a mounting device adapted to be removably connected to the trackway. The trackway includes an elongated channel member having a back wall and two side walls with in-turned flanges at their outer ends to present a lengthwise slot. An insulative member is mounted within the channel member and includes a pair of spaced apart receptacles in alignment with the lengthwise slot and a pair of conductors which extend through the receptacles in a lengthwise direction. The mounting device is assembled in a hollow housing having an open end. A plug unit closes the open end and includes an insulative head member and a pair of contact blades extending outwardly through the insulative head member which are spaced apart to align with the pair of receptacles. The mounting device also includes a latching means for engaging and holding the inside surfaces of the in-turned flanges upon the contact blades being inserted into the receptacles, and a releasing means for selectively disengaging the latching means to permit the removal of the mounting device from the trackway.

DESCRIPTION OF DRAWINGS

For a better understanding of this invention, reference may be made to the accompanying drawings, in which:

FIG. 1 is a broken perspective view illustrating a portion of the track light system embodying the present invention with two mounting devices shown connected in the trackway and a third mounting device shown in spaced relation relative to the trackway;

FIG. 2 is a partial front view of FIG. 1 showing one of the mounting devices fastened to the trackway and illustrating a portion of the trackway in cross section;

FIG. 3 is a cross sectional view of FIG. 2 taken along the line 3--3 and looking in the direction of the arrows;

FIG. 4 is a cross sectional view of the mounting device embodying the principles of my invention taken along the line 4--4 of FIG. 2 and looking in the direction of the arrows;

FIG. 5 is a cross sectional view taken along the line 5--5 of FIG. 4 and looking in the direction of the arrows; and

FIG. 6 is an enlarged view of a portion of FIG. 4 showing the channel member in cross section.

DESCRIPTION OF PREFERRED EMBODIMENT

There is shown in FIG. 1, a track light system embodying the principles of this invention in which an elongated trackway 10 is supported from a suspended ceiling 12. The elongated trackway 10 is illustrated as being mounted to the suspended ceiling by means of a plurality of spread-type wing nuts 14 (FIG. 2).

The elongated trackway 10 comprises a central channel member 16 (FIG. 4) and a pair of circuit wireways disposed on the two lateral sides of the central channel member 16. The central channel member 16 comprises a back wall 22 and two side walls 24 with a pair of in-turned flanges 26 projecting towards each other from the outer ends of the side walls 24. The space between the in-turned flanges 26 defines trackway slot 25. The trackway 10 is preferably made from a light weight material, such as aluminum and could be die casted into a one-piece construction. A removable cover 30 fits between the opposing grooves formed by the pair of inwardly facing spaced apart ridges 32 and 34 which are provided at the upper ends of the lateral side walls 36 and 38, respectively.

A bus bar assembly 40 (FIGS. 4-6) is mounted lengthwise within the channel member 16 and comprises an elongated insulative member 42 which carries a pair of electrical conductors 44 in spaced apart relation. The two conductors extend transversely through a pair of receptacles 46, 48 that open downwardly in alignment with lengthwise slot 25.

The insulative member 42 has a generally U-shaped central portion 50 having a bight portion 52 and a pair of generally parallel arm portions 54, 56. At the outer ends of arm portions 54, 56, there is formed a pair of out-turned flanges 58 and 60, respectively. The pair of receptacles 46 and 48 are defined, respectively, by a pair of spring-biased finger members 62 and 64, and the adjacent side wall surfaces of arm portions 54 and 56. The spring-biased fingers 62 and 64 extend downwardly from the intermediate portion of flanges 58 and 60, respectively, in a transverse direction towards side walls 54 and 56 such that their outer ends tend to close the respective receptacle openings. The outer ends of spring biased fingers 62 and 64 are provided with arcuate portions 66 and 68, respectively, which generally conform to the curvature of the conductors 44.

The entire insulative member 40 is preferably made as a molded part from a material having good elasticity characteristics such as rigid vinyl. The insulative member 40 is mounted within the channel member by squeezing together the arm portions 54 and 56 to cause the out-turned flanges 58 and 60 to be brought together a sufficient amount to permit their outer edges to be inserted into the grooves 70 and 72, which grooves are formed between the back wall 22 and the respective elongated ridges 74 and 76 projecting from the inner surface area of side walls 24.

Referring to FIGS. 2 and 3, there is shown one end of trackway 10 in which the input connection to bus bar assembly 40 is illustrated. The ends of trackway 10 are closed off by means of junction boxes 41, 43 which are adapted to carry the supply wires for energizing the conductors 44. The conductors 44 are connected through a pair of electric couplers 45 to a pair of supply wires 47 which extend through back wall 22, cover plate 30 and outlet plate 49 for opening 51 in ceiling 12.

The mounting device 80 for connecting an electrical fixture 82 (FIG. 1) or similar electrical unit into the trackway 10 will now be described.

The mounting device 80 is housed in a hollow casing 84 having a generally cylindrical configuration. Casing 84 has a closed end 86, and an open end 88 which is presented at the outer end of the outward flared skirt portion 90. A plug unit 92 fits snugly into the open end 88 and comprises an insulative head member 94 and a pair of contact blades 96. The outer dimensions of the head member 94 conform to the dimensions of the flared skirt portion 90 at its outer end to provide a snug fit therebetween.

The pair of contact blades 96 are provided with an intermediate offset portion 98 which project through a pair of spaced openings 100 formed axially at the center portion of head member 94. The outer ends 102 of the contact blades 96 project outwardly of the head member 94 in a normal relation therewith and are spaced apart a distance equal to the distance between receptacles 46, 48.

The contact blades 96 of the plug unit 92 are electrically connected to the electrical fixture 82 and this electrical connection includes a pair of leads 104 connected between the tail end of the blades 96 and on-off switch 106 contained within housing 84 and having a two-position switch lever 108 (FIG. 2) extending from one of the side walls of the cylindrical case 84. The leads between the electrical fixture 82 and the switch 106 pass through a coupler unit 108, which also secures the U-shaped mounting bracket 110 of electrical fixture 82 to the cylindrical housing 84 of mounting unit 80. Coupler 108 comprises the combination of bushing 110 in threaded engagement with hex nut 112. It will be appreciated that the electrical fixture 82 comprises no part of this invention and it is merely illustrated as a typical use for the mounting device 80.

To hold the mounting device 80 and associated lighting fixture 82 in a locked relation with the trackway 10, the mounting device 80 has a latching means 116 in the form of a pair of cooperating spring-biased latching arms 118. Latching means 116 is fabricated as a one-piece part fabricated from a suitable material having good resilient properties such as spring steel and bent into a generally U-shaped configuration. Its bight portion 120 is secured to the closed end 86 of the housing 84 and its pair of arms 116, 118 extend lengthwise of the casing 84 outwardly through the openings in head member 94 with their outer end portions bent into oppositely extending closed loops 122, 124, respectively. The outwardly extending transverse portions 123, 125 of closed loops 122, 124 are shaped to present camming surfaces to guide the outer ends of the arms 116, 118 towards each other upon their respective riding engagement with the inner edge of in-turned flanges 26 as the mounting device is inserted into the trackway.

The spring tension of the arms 116, 118 urges them outwardly such that when the mounting device 80 is inserted into the trackway 10, the loop portions 122, 124 expand outwardly as shown in FIG. 4 to provide a latching engagement with the pair of in-turned flanges 26. To selectively disengage the latching means, a releasing means is provided in the form of a pair of eject buttons 128 and 130 connected in a crosswise relation to the intermediate portion of the arms 116, 118, respectively, and projecting through openings 132, 134, respectively, of cylindrical casing 84. By squeezing inwardly on the eject buttons 128 and 130 simultaneously the latching arms 116, 118 are brought inwardly to the dotted line position of FIG. 4 to permit the removal of the mounting device 80 from the trackway 10.

To insure that there is correct polarity between the electrical fixture and trackway 10, polarizing means are provided in the form of locating rail 140 projecting downwardly from flange 26 of channel member 16 which mates with a conforming groove 142 in the outer face of head member 94 when the mounting device 80 is properly inserted in the trackway. If the mounting device were turned through a 180 degree angle from that depicted in FIG. 4, locating rail 140 would prevent the insertion of plug unit 92 into the channel member.

From the above it will be readily apparent that this invention permits connection through an electrical power track of an electrical fixture by a simple operation of inserting the plug unit into the trackway. By virtue of the mating relationship between the locating rail 140 and groove 142 the correct polarity between the plug unit and trackway is always assured.

Claims

We claim:

1. In an electric distribution system, a metallic channel member (16) having a base (22) and lateral flanges (24), a longitudinally extending body of resilient insulation (42) carried in the body of said channel (16) and having a pair of longitudinally extending flanges (62-64) one on each side of the body of insulation, said longitudinally extending flanges extending towards the open side of the first named channel, there being grooves extending longitudinally of said channel member formed in the flanges thereof adjacent their outer ends, said grooves facing towards each other, bare conductors (44-44) carried in said grooves, and a take-off plug having prongs thrust between said longitudinally extending conductors and said body of insulation, transversely of the longitudinally extending conductors.

2. The combination of claim 1 wherein said flanges of the channel (16) have inwardly extending shoulders (26) facing towards each other, and holding means (123-124) on said take-off plug to hold the plug against removal and laterally depressable release means (120-130) for releasing said plug holding means.

3. In a system of the class described, a longitudinally extending metallic channel (22) having a horizontal base and downwardly extending side walls, said side walls carrying parallel inwardly extending flanges facing each other, an insulating body carried on the base of the channel and comprising a longitudinally extending spacer member of insulation, said spacer member having substantially parallel longitudinally extending vertical side walls and resilient conductor carrying walls, said latter walls being supported on and spaced from said side walls of insulation and having open longitudinal conductor retaining grooves, longitudinally extending bare conductors in said grooves and a plug connector member having parallel prongs thrust between said vertical side walls and said conductor carrying walls and releasable latch means on said plug member which engage with said flanges on the metallic channel member.

4. The combination of claim 3 wherein said downwardly opening metallic channel (22) has horizontally extending facing flanges (26) and said plug member which carries the contact blades (102) carrying spring pressed detents (122) for moving radially outward to overhang the flanges (26).

5. In a power distributing system of the class described a trackway comprising an elongated metallic housing of channel shape cross-section embodying a downwardly open channel portion having a back wall and depending side walls terminating in horizontally inwardly extending flanges, an upwardly facing conductor carrying channel of insulation having a bottom wall and vertically extending side walls, anchoring means for anchoring the said side walls to the metallic channel adjacent the back wall thereof, dependent conductor supporting flanges of insulation joined at their upper edges to the side walls of said channel of insulation adjacent the upper edges of the latter, said depending conductor supporting flanges containing laterally open tubular conductor receiving seats, electric conductor wires seated in said seats and being disposed adjacent the side walls of said channel of insulation, and a cooperating plug having conducting blades for attachment to a take-off circuit, said blades being thrust endwise between said support flanges (44) and the adjacent side walls of insulation of said channel of insulation (42), and contacting said conducting wires.