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Publication numberUS3601749 A
Publication typeGrant
Publication dateAug 24, 1971
Filing dateMay 26, 1969
Priority dateJul 22, 1968
Also published asDE6928817U
Publication numberUS 3601749 A, US 3601749A, US-A-3601749, US3601749 A, US3601749A
InventorsDavis Robert, Hart Derek James
Original AssigneeBritish Lighting Ind Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Input connector for electric distribution tracks
US 3601749 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent I I I Inventors Derek James Hart;

Robert Davis, both of London, England Appl. No. 827,820

Filed May 26, I969 Patented Aug. 24, I971 Assignee British Lighting Industries Limited London, England Priority July 22, 1968 Great Britain 34942/68 INPUT CONNECTOR FOR ELECTRIC DISTRIBUTION TRACKS 2 Claims, 1 Drawing Fig.

US. Cl 339/14 R, 339/22 B Int. Cl ll0lr 3/06 Field olSearch 339/l4,2l,

[56] References Cited UNITED STATES PATENTS 1,645,650 10/1927 Kirkman 339/174 2,309,972 2/1943 Messingm. 339/76 2,464,964 3/ I 949 Charap 339/21 2,943,292 6/ I 960 Herrmann et al 339/21 X 3,08 I ,442 3/1963 Platz 339/14 Primary ExamineP-Emest R. Purser Assistant Examiner-Robert A. Hafer AttorneyJoseph C. Ryan ABSTRACT: An input connector for connecting a distribution track to an electricity supply has a pair of movable conductor elements provided with terminals for wiring to the supply, the input connector having a cam assembly, for moving the conductor elements into a position in which the conductor elements (i) make contact with exposed track conductors housed in the distribution track and (ii) clamp the input connector to the track.

PATENTED M1824 l9?! DEREK JAMES HART ROBERT DAVIS ATTORNEY INPUT CONNECTOR FOR ELECTRIC DISTRIBUTION TRACKS The present invention relates to an input connector for electric distribution tracks. The input connector allows a mains electricity supply to be readily applied an electric distribution track of the type which houses bare track conductors. The connector is particularly, although not exclusively, suitable for use with a distribution track such as the one described in our copending application of even date entitled: Track for Distribution of Electricity" Ser. No. 827,656, now U.S. Pat. No. 3,546,367.

According to the present invention, there is provided an input connector for an electrical distribution track in which bare track conductor elements are carried, the connector comprising a casing in which a pair of conductor elements are mounted side by side, the conductor elements being insulated from one another and having terminals for connecting input leads thereto, means being provided to move the conductor elements into abutment with the track conductors to provide electrical contact and to clamp the connector to the track.

The use of the input connector avoids the necessity of making more-or-less permanent connections of a mains supply cable to the track. The only permanent connections necessary are between leads of the mains supply cable and the terminals of the input connector. The input connector can be readily locked to and release from the track. Furthermore, the input connector can be locked to the track at any convenient location along the track, normally adjacent a mains supply outlet. Electrical connection of the leads of the mains supply cable and the track conductors is obtained by means of conductor elements carried by the input connector. The conductor elements are movable into engagement with the track conductors when input connector is positioned on the track. Preferably the movement of the conductor elements is controlled by a cam which is operable from the exterior of the input connector. When the conductor elements are in contact with the track conductors, the input connector is clamped to the track. In addition, the connector will preferably include a separate contact element so that an earth line can be connected to a further conductor carried by the track.

The present invention will now be described by way of example with reference to the accompanying drawing, which is an exploded perspective view of an input connector and part of an electric distribution track.

For clarity, a brief description of an electric distribution track will be given. The track consists of an elongate member which is, for example, an extrusion of a plastics material such as P.V.C. The track has a base 11 and sides 12, 13 extending perpendicularly from the longitudinal edges thereof. The sides 12, 13 include housings in which track conductor strips 14, 15 are carried. The track conductors l4, 15 are accessible from the inner region of the track 10 by way of slots 16, 17. A further track conductor 18 is supported in the base 11 of the track 10, and is used to provide an earth line. The sides 12, 13 of the track 10 additionally include flanges 22, 23 which are located remote from the base 11, and which project inwardly from the sides 12, 13. As viewed in the drawing, the flanges 22, 23 have downwardly projecting extensions 24, 25, so that a pair of grooves 26, 27 are formed between the extensions 24, 25 and the sides 12, 13. The flanges 22, 23 and the grooves 26, 27 extend longitudinally along the track 10.

The input connector 30 shown in exploded perspective includes a casing 31 which is made from a rigid plastics material such as P.V.C. The casing 31 has a central dividing wall 32 which separates the easing into two compartments. A pair of conductor elements 33, 34 are provided, one of which is mounted inside each of the compartments. The conductor elements 33, 34 are therefore kept insulated from one another by the dividing wall 32. The conductor elements are made from a resilient material such as brass, and each carries a barrel-type screw connector 35, 36 with associated screws 35', 36. An

end face 37 of the casing 31 is provided with apertures 38 so that leads of a main supply cable (not shown) can be inserted through the wall 37 for clamping in the barrel connectors 35, 36.

As will be seen from the drawing, the conductor elements 33, 34 are bent to form contact fingers 40 for engaging the track conductors 14, 15. The conductor elements 33, 34 are additionally bent remote from the contact fingers 40, at 41 in the drawing, so that the distance between the contact fingers 40 is less than the distance between the track conductors 14, 15. When the input connector 30 is positioned on the track 10 the contact fingers 40 are moved apart from their innermost positions so that each contact finger 40 touches its associated track conductor.

The contact fingers 40 are moved apart by means of a cam arrangement which is operable from the exterior of the casing 31. The cam arrangement is constituted by a generally elliptical cam 42, a cam seat 43 and a camshaft 44. The cam arrangement is assembled within the casing as follows. The camshaft 44 is passed through an aperture 45 provided in the base of the casing 31, so that the head 46 of the camshaft 44 is accessible from the exterior of the casing 11. The head 46 of the camshaft is slotted so that the shaft may be rotated by means of a screwdrive or the edge of a coin. The cam seat 43 is then positioned in the casing 31, on top of the conductor ele ments 33, 34. A further aperture 47 is provided in the cam seat 43 through which the camshaft 44 extends. The cam 42 is then positioned on a square portion 48 of the camshaft 44. The cam 42 can be retained on the camshaft 44 by conventional means such as spreading the end of the cam shaft 44. Otherwise, the cam can be retained on the camshaft 44, for example by using a circlip (not shown). The cam 42 and its associated cam seat 43 are made from insulating, plastics materials such as acetal. A pair of arcuate-inclined surfaces 49 are formed on the surface of the cam seat 43 which contacts the cam 42. The inclined surfaces project from the surface 50 of the cam seat 43 to the raised portion 51, which includes sur faces 51a, 51b, forming rotational limit stops for the cam 42. When the camshaft 44 is rotated so as to align the cam 42 with its major axis across the housing 31, the cam 42 moves the contact fingers 40 apart laterally, against the bias of the conducting elements 32, 33, into an on) position. The required rotation is therefore anticlockwise as viewed from above. The conducting members 32, 33 bias the cam seat 43 into abutment with the base of the cam 42, so that on rotation, the cam rides on the inclined surfaces 49. The cam is locked in the on position by flats formed on its camming surface which engage the contact fingers 40, and further rotation in the same direction is prevented by the limit stop 51a. If the cam 42 is now rotated through approximately in a clockwise direction, it rides over the inclined surfaces 49 thus moving the cam seat 43 in a downward direction along the camshaft 44'against the bias of the conducting members 32, 33, which exerts a corresponding camming action on the contact fingers 40. The 90 rotation aligns the cam 42 with its major axis parallel to the longitudinal axis of the housing 31, the contact fingers then being in their innermost or off position. Further rotation in this direction is prevented by the limit stop 51b. Operation of the cam assembly therefore causes a lateral movement of the contact fingers 40, together with up-anddown movement thereof caused by the camming action effected by movement of the cam seat 43 along the camshaft.

As will be seen from the drawing, the end face 37 of the easing 31 also includes an aperture 52, through which an earth lead of a mains cable can be threaded. A contact member forming an earth spring 53 is so positioned on the casing 31 a as to touch the further track conductor 18 when the input connector is clamped to the track 10. The earth lead is connected to the earth spring 53 by means of a bush 54 in which the lead is clamped, for example with a grub screw.

Although not shown in the drawing, the casing 11 can include a pair of flanges on the lower long edges 55 of the cas ing. The flanges can be so formed as to engage in the grooves 26, 27 which extend longitudinally along the track 10.

To supply power to the track conductors 14, the mains supply leads are connected to the input connector 30 as described. The cam shaft 44 is rotated to bring the cam 42 into a position in which the contact fingers 40 are in their innermost position. The input connector is then pushed up into the track 10. The cam shaft 44 is rotated through 90, so that the cam 42 moves the contact fingers 40 apart. When so moved, the contact fingers project through passages 16, 17 of the track 10 to touch the track conductors l4, 15. The cam 42 locks in this position, as described above. The input connector 30 is clamped to the track 10 when the contact fingers touch the track conductors, and is prevented from disengaging with the track 10 by abutment of the contact fingers 40 with the lower surfaces of the passages l6, 17. The input connector 30 is released from the track 10 by rotating the cam allowing the contact fingers to retract into their innermost positions out of engagement with the track conductors, 14, 15. It will be appreciated that, although the clamping means is constituted by the cam assembly and the contact fingers, separately operable clamping means could be used. The input connector can be clamped to the track at my We claim:

1. An input connector for an electricity distribution track in which exposed track conductors are housed, the input connector comprising:

a casing,

a pair of conductor elements, insulated from one another which are mounted within said casing,

input terminals on said conductor elements for connecting input leads thereto, and

a cam assembly operable from the exterior of the casing for moving said conductor elements between inner and outer positions,

whereby said conductor elements, when moved apart to their outer positions, clamp the input connector to the track with said conductor elements in contact with the track conductors,

said cam assembly comprising a cam, a camshaft a and a cam seat mounted for movement along the cam shaft, said cam seat being biased against the cam by said conductor elements, and said cam seat having a pair of arcuate-inclined surfaces for coaction with said cam, whereby rotation of said cam, in addition to causing lateral movement of the contact fingers between their inner and outer positions, effects a camming action on said conductor elements by allowing movement of said cam seat along the camshaft.

2. An input connector according to claim 1, wherein said cam seat includes rotational limit stops for said cam.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1645650 *Apr 11, 1925Oct 18, 1927Watts Kirkman ThomasElectric plug
US2309972 *Aug 15, 1941Feb 2, 1943Bulldog Electric Prod CoConnector
US2464964 *Jun 25, 1945Mar 22, 1949Charap Norman NSelective station electrical outlet molding
US2943292 *Jan 3, 1956Jun 28, 1960Ite Circuit Breaker LtdElectric receptacle
US3081442 *May 28, 1958Mar 12, 1963Ite Circuit Breaker LtdThree contact twist type receptacle
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3825879 *Aug 2, 1972Jul 23, 1974Hesse KAdapter for current distributor rail
US4729742 *Aug 22, 1986Mar 8, 1988Matsushita Electric Works, Ltd.Electric power distribution track
U.S. Classification439/94, 439/117
International ClassificationH01R25/14, H01R25/00
Cooperative ClassificationH01R25/145
European ClassificationH01R25/14D