US3832503A - Two circuit track lighting system - Google Patents

Abstract

A device is provided for connecting an electrical fixture to a three-conductor, two-circuit power distribution track. The device includes a housing adapted to be secured to the track containing a fixed contact adapted to engage one conductor and a movable contact adapted to be shifted to a proper position to engage either of the other two conductors. Movement of the second contact is controlled by an indicator which extends outside the housing. The indicator assumes two positions corresponding to the positions of the contact with both positions being readily visible when the device is secured to a track so as to provide a clear indication of the circuit associated with the fixture.

Description

United States Patent 11 1 Crane [451 Aug. 27, 1974 [73] Assignee: Keene Corporation. New York,

[22] Filed: Aug. 10, 1973 [21] Appl. No.: 387,387

Roy B. Crane, Wilmington, Mass.

[52] US. Cl. 200/51 R, ZOO/51.07. 339/21 R [51] Int. Cl ..H01r 13/70 [58] Field of Search 339/20-24, 339/119.14;200/51R.51.07

[56] References Cited UNITED STATES PATENTS 3.496.518 2/1970 Neumunn et ul 339/21 R 3.737.834 6/1973 Contrutto 339/21 R Primary E\'uminerDz1vid Smith. Jr.

Attorney, Agent. or FirmDa1simer, Kane, Sullivan & Kurucz Kane 1 5 7 1 ABSTRACT A device is provided for connecting an electrical fixture to a three-conductor, two-circuit power distribution track. The device includes a housing adapted to be secured to the track containing a fixed contact adapted to engage one conductor and a movable contact adapted to be shifted to a proper position to engage either of the other two conductors. Movement of the second contact is controlled by an indicator which extends outside the housing. The indicator assumes two positions corresponding to the positions of the contact with both positions being readily visible when the device is secured to a track so as to provide a clear indication of the circuit associated with the fix- 7 Claims, 6 Drawing Figures TWO CIRCUIT TRACK LIGHTING SYSTEM BACKGROUND OF THE INVENTION The present invention relates to electrical fixtures adapted to receive power from distribution tracks and more particularly to means for connecting a fixture to either of the circuits of a three-conductor, two-circuit track.

In recent years track lighting systems have gained in popularity for both commercial and residential applications. The systems consist basically of a channel-type track, the internal sides of which support elongated conductors which may be tapped at any point along their length by suitable connectors to provide power for fixtures mounted to the track. The fixtures may then be used as spotlights, accent lights or to provide general illumination for an area.

The number of fixtures which can be supported by a track is limited to a large extent by the current which the conductors can carry which generally is not greater than amps. In order to increase the track capacity electrical load, it has been suggested that a second circuit, in the form of a second power conductor be introduced into the track and various schemes have developed to enable a fixture to be connected to either of the two circuits (see for example, US. Pat. Nos. 3,496,518, 3,559.l46 and 3,613,045). In these arrangements, the power conductors are positioned on one side of the channel vertically spaced apart from each other and a common neutral return conductor is provided on the other side of the channel.

Since the two power conductors are vertically separated from each other, the associated connector requires a vertically shiftable contact which can be positioned to make electrical connection with either power conductor as required. To this end, the prior art suggests various shim arrangements designed to maintain the shiftable contact in the desired raised or lowered position. Because all the electrical interconnections between the conductors and fixture connector are made within the track channel, a major problem with such prior art connectors is that once installed, there is no way to readily determine which circuit a particular fixture is connected to. This poses both maintenance and safety problems. This is especially so where one of the power leads carries a relatively low power audio signal for speaker fixtures which may be mounted to the track and the other carries power to light fixtures mounted to the same track.

In view of the above, the principal object of the present invention is to provide an improved threeconductor, two-circuit track connector which may readily be shifted between circuits and which, when in position. gives ready, visible indication of the circuit to which an associated fixture is connected.

SUMMARY OF THE INVENTION The above and other beneficial objects and advantages are attained in accordance with the present invention by providing an improved connector adapted to connect an electrical fixture to a three-conductor track of the type having two opposed sides with a first conductor extending longitudinally along one side and the second and third conductors spaced vertically apart from each other extending along the opposite side. The connector comprises a housing having means thereon for securing the connector to the track in locking engagement. A first contact extends from the housing adapted to engage the first conductor when the housing is locked in position. A second, vertically shiftable contact also extends from the housing. The second contact is shiftable between a first position for engagement with the second conductor and a second position for engagement with the third conductor when the housing is in locked position. Means are provided for shifting the second contact between positions and indicator means in controlling relationship with the shifting means are provided. The indicator means assumes a first, clearly visible position when the second contact is in its first position and a second, clearly visible position when the contact is in its second position.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings:

FIG. 1 is a fragmentary perspective environmental view of a track lighting system incorporating the improvement of the present invention;

FIG. 2 is a perspective view of the improved connector of the present invention;

FIG. 3 is a fragmentary sectional view taken along reference lines 33 of FIG. 2 in the direction indicated by the arrows shown with an associated track which is also in section;

FIG. 4 is a sectional view taken along reference lines 4-4 of FIG. 3 in the direction indicated by the arrows;

FIG. 5 is a fragmentary sectional view taken along reference lines 5-5 of FIG. 2 in the direction indicated by the arrows; and,

FIG. 6 is a sectional view taken alongreference lines 66 of FIG. 3 in the direction indicated by the arrows.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Reference is now made to the drawings wherein similar components bear the same reference numeral throughout the several views. Accordingly, in FIG. 1 there is shown a track lighting system 10 installed on a wall orceiling 12. The system comprises anelongated track 14 secured to the ceiling bysuitable bolts 16 and capped at its ends byclosures 18.

Referring briefly to FIG. 3, it will be noted thattrack 14 is formed with a series of internal flanges. Accordingly, on oneside 20 oftrack 14 the internal flanges support an insulator 22 which in turn carries asingle conductor 24. On the opposite side 26 oftrack 14 the flanges supportinsulator 28 which in turn carries a pair ofconductors 30 and 32 spaced vertically apart from each other. The twoconductors 30 and 32 may be connected to separate power supply circuits or, one of the circuits may be used to carry power to light fixtures while the other circuit carries audio signals to appropriate speakers. Thesingle conductor 24 provides a common neutral return for bothactive conductors 30 and 32. The present invention is particularly adapted to the latter arrangement since any inadvertent connection of a speaker to a power line could cause irreparable damage to the speaker. The threeconductors 24, 30 and 32 extend along substantially the entire length of the track permitting contact to be made at any point along their length.

Thetrack 14 further includes internal flanges 34 (a and b) and 36 (a and b) which cooperate withmating parts 38 and 40 of aconnector 42 to secure the connector to the track in locking engagement. The distance betweenflanges 34a and 34b differs from that between 36a and 36b as do the corresponding dimensions ofmating parts 38 and 40 so that the connector is polarized in the manner in which it may be mounted to the track. That is,mating part 40 only fits between flanges 36a and 36b and will not fit betweenflanges 34a and 34b.

Referring to FIGS. 1 and 2, theconnector device 42 is shown comprising anelongated housing 44 having a bottom opening 46 to receive a suitable fastener to se' cure afixture 48 andthrough which a power lead can pass and a side opening 47 for a toggle switch. Alocking tongue 52 extends from thetop surface 54 of the housing. Thetongue 52 is dimensioned to fit between the bottom flanges 34b and 36b of the track and serves to prevent rotation of the housing once in position. As shown in FIG. 5, atab 56, which extends outside the housing is connected to the tongue and permits the tongue to be retracted into the housing during installation whereafter a biasing spring 58 serves to urge the tongue outwardly to lock in position between the bottom track flanges and thereby lockconnector 42 in position.

As also shown in FIG. 2, themating parts 38 and 40 of the connector extend radially outwardly from opposite sides of acentral shaft 60 which in turn extends up wardly through the top surface 54 f the housing. The center ofshaft 60 is hollow thereby providing access to the interior of the housing. A pair ofcontacts 62 and 64 extend outwardly from the opening in the top of the shaft. Each of the contacts has a 90 bend adjacent the top end thereof defining top portions extending parallel tomating parts 38 and 40 and away from each other. Accordingly, contact 62top portion 66 extends radially outwardly parallel topart 38 andcontact 64top portion 68 extends radially outwardly parallel topart 40.Contact 62 is coupled throughconnector 57 to wire 59 which along with a similar wire (not shown) connected to contact 64 comprises the power lead 50 which feedsfixture 48 fromconductors 24 and 30 or 32.

Still referring to H6. 3, it can be seen thatcontact 62 is provided with adimple 63 which fits in arecess 65 on the inside wall ofshaft 60. This serves to fix the contact with respect to the shaft. It should also be noted that thetop portion 66 ofContact 62 is designed to make electrical contact withconductor 24 when the connector is in position.Contact 64 is fixed to anelongated rod 72 positioned for movement within thebase ofshaft 60. To this end.rod 72 is formed with a longitudinal slit extending downwardly from its top end and the body portion ofContact 64 is positioned in the slit. A stake 70 is formed in the contact which engages a recess 71 inrod 72 and thus firmly securescontact 64 to the rod. Thetop end 68 ofcontact 64 is bent over the top of the rod extending away fromcontact 64 and designed to make contact withconductors 30 or 32 as will be described forthwith.Rod 72 is formed of a plastic insulating material and thus serves to provide insulation between the contacts over their entire lengths.

As stated,rod 72 is disposed for vertical movement within the housing with its top end adapted to extend through the opening in the top of the shaft. When the rod is in its raised position and the connector is secured to a track.contact 64top portion 68 is in position to make electrical contact with theupper conductor 32 of the track as shown in solid line in F IG. 3. When the rod is in its lowered position, the top portion of the contact is in position to make electrical contact with the lower conductor 30 of the track as shown in phantom in F IG. 3. In both positions,rod 72 fully insulates thecontacts 62 and 64 from each other.

Rod 72 is formed with anintegral tab 74 which extends out horizontally. Thetab 74 rides in aslot 76 provided in a horizontallyshiftable indicator bar 78 theend sections 80 and 82 of which are adapted to pass throughopenings 81 and 83 in theends 84 and 86 respectively ofhousing 44 as shown in FIGS. 1, 2 and 6. Referring to FIG. 4, it can be seen that theslot 76 ofbar 78 includes an inclined portion 88 the height and depth of which are such as to be able to receivetab 74.Bar 78 is constrained to horizontal movement by thehousing top surface 54 in combination with the surfaces of housing ends 84 and 86 surrounding-openings 81 and 83. In addition, aferule 90 secured in position byscrew 92 helps maintain alignment ofbar 78 and keepstab 74 captive inslot 76 by limiting horizontal movement of the bar.Screw 92 further cooperates withscrew 94 in securing thetop surface 54 of the housing in position.

Sincetab 74 is captive inslot 76, asbar 78 is shifted back and forth, the tab will ride up and down inclined portion 88 of the slot following the incline of the slot which serves as a cam. This movement of the tab causes a vertical movement of the connectedplastic part 72 and the attachedcontact 64. The slot is suitably inclined so that the vertical movement ofrod 72 corresponds to the vertical distance betweenconductors 30 and 32. Thus, the horizontal position ofbar 78 determines the vertical position ofrod 72 and hence determines which of the vertically spacedconductors 30 or 32 will be contacted by thetop portion 68 ofcontact 64.

The bar is dimensioned and the inclined portion of slot 88 is positioned so that a portion ofbar 78 extends out of one end of the housing only when thecontact 64 is in its fully raised position and the bar extends out of the other end of the housing only when the contact is in its fully lowered position. Further, since theconnector 42 is polarized in the manner described before to fit into the track in a particular orientation, the position ofbar 78 and more specifically a determination of which end 80 or 82 extends from the housing is indicative of which of theconductors 30 or 32 is electrically connected to contact 64 and hence which circuit is feeding the associated fixture. If desired, the ends ofbar 78 may be color coded and elongated to facilitate visual determination of the active circuit.

Thus, in accordance with the above, the aforementioned objectives are effectively attained.

Having thus described the invention, what is claimed l. A device adapted to connect an electrical fixture to a three-conductor track of the type having two opposed sides with a first conductor extending longitudinally along one side and second and third conductors spaced vertically apart from each other extending along the opposite side. said device comprising: a housing; means on said housing for mechanically securing said device to said track; a first contact extending from said housing adapted to engage said first conductor when said housing is in said secured position; a second contact extending from said housing, said second contact being vertically shiftable between a first position for engagement with said second conductor and a second position for engagement with said third conductor; means for switching said second contact between positions; and indicator means extending from said housing in control relationship with said switching means, said indicator means assuming a first indicator position when said second contact is in its first position and a second indicator position when said second contact is in its second position, both of said indicator positions being readily visible when said housing is locked to said track.

2. The invention in accordance with claim 1 wherein said second contact is constrained to vertical movement within said housing, said indicator means comprises a bar disposed for horizontal movement through said housing, and said switching means comprises cooperating means coupled to said second contact and horizontal bar for translating horizontal movement of said bar to vertical movement of said contact.

3. The invention in accordance with claim 2 wherein said translating means comprises a cam mounted to one of said bar or second contact and a follower mounted to the otherof said bar or second contact.

4. The invention in accordance withclaim 3 further comprising a rod coupled to said second contact and adapted to move therewith, said rod being interposed between and insulating said first and second contacts from one another.

5. The invention in accordance withclaim 4 wherein said cam comprises an inclined slot carried by said bar and said follower comprises a tab extending from said rod and constrained to ride in said slot.

6. The invention in accordance with claim 2 wherein said bar has a first end section adapted to extend through one end of said housing only whensecond contact is in its first position and an opposite end section adapted to extend through an opposite end of said housing only when said second contact is in its second position.

7. The invention in accordance withclaim 6 wherein said bar end sections are color coded.

Claims (7)

1. A device adapted to connect an electrical fixture to a threeconductor track of the type having two opposed sides with a first conductor extending longitudinally along one side and second and third conductors spaced vertically apart from each other extending along the opposite side, said device comprising: a housing; means on said housing for mechanically securing said device to said track; a first contact extending from said housing adapted to engage said first conductor when said housing is in said secured position; a second contact extending from said housing, said second contact being vertically shiftable between a first position for engagement with said second conductor and a second position for engagement with said third conductor; means for switching said second contact between positions; and indicator means extending from said housing in control relationship with said switching means, said indicator means assuming a first indicator position when said second contact is in its first position and a second indicator position when said second contact is in its second position, both of said indicator positions being readily visible when said housing is locked to said track.

2. The invention in accordance with claim 1 wherein said second contact is constrained to vertical movement within said housing, said indicator means comprises a bar disposed for horizontal movement through said housing, and said switching means comprises cooperating means coupled to said second contact and horizontal bar for translating horizontal movement of said bar to vertical movement of said contact.

3. The invention in accordance with claim 2 wherein said translating means comprises a cam mounted to one of said bar or second contact and a follower mounted to the other of said bar or second contact.

4. The invention in accordance with claim 3 further comprising a rod Coupled to said second contact and adapted to move therewith, said rod being interposed between and insulating said first and second contacts from one another.

5. The invention in accordance with claim 4 wherein said cam comprises an inclined slot carried by said bar and said follower comprises a tab extending from said rod and constrained to ride in said slot.

6. The invention in accordance with claim 2 wherein said bar has a first end section adapted to extend through one end of said housing only when second contact is in its first position and an opposite end section adapted to extend through an opposite end of said housing only when said second contact is in its second position.

7. The invention in accordance with claim 6 wherein said bar end sections are color coded.

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