The invention relates to specialized forms of adjustably positioned lighting fixtures, as frequently used in commercial and theatrical lighting, and particularly to features thereof to accommodate and facilitate periodic adjustment.
Specialized lighting fixtures, such as theatrical lighting, and various forms of commercial lighting fixtures are constructed to provide for accurate aiming of a light beam. In many cases, after a lighting fixture is initially installed, it may be adjusted one or more times until a desired effect is achieved. At that juncture, it may be desired to tightly lock the adjustments, so that vibrations and other external influences will not, over time, result in undesired movements in the adjusted position of the fixture. For effectively tight locking of the adjustments, a tool frequently is required. However, if the workman does not have the correct tool at the proper time, the final locking of the adjustments may not be carried out.
The invention is directed to an improvement in adjustable lighting fixtures of the type described, particularly for track lighting systems, which include novel and effective facilities for housing a locking tool in the fixture itself in a reliable and secure manner, easily accessible to a workman. Typically a suitable locking tool is an Allen key, of a size to be engageable with one or more Allen screws provided on the fixture, for securely tightening the fixture in an adjusted position when appropriate and desired. The Allen key is mounted in a convenient manner and location, easily accessible to the workman, yet is securely retained against accidental dislodgment and loss, and is easily replaced by the workman when finished with the locking operations.
An advantageous form of track lighting fixture of existing design includes a mounting body arranged to be received within a downwardly opening recess of a bus bar containing conductive elements for operating lighting fixtures positioned anywhere along the bar. The mounting body includes a rotatable element carrying electrical contacts and a clamping element, all operated by a rotatable locking lever accessible at the bottom of the mounting body. After the mounting body is positioned in the bus bar, the locking lever is rotated such that the electrical and the clamping elements are rotated into engagement with the bus bar, securing the fixture in position and engaging its electrical contacts with the conductors of the bus bar. The new fixture incorporates a novel and specialized design of locking lever, which enables it to conveniently house an Allen key in a secure manner which is at the same time easily accessible to a workman for locking an adjusted lighting fixture in a desired orientation and also conveniently restored to its position within the locking lever so as to be available for a future occasion. The proper tool thus always accompanies the fixture and is always available to a workman installing, re-installing and/or adjusting the fixture.
For a more complete understanding of the invention reference should be made to the following detailed description of a preferred embodiment thereof and to the accompanying drawings.
Referring now to the drawings, the reference numeral 10 designates generally a track lighting fixture which, except for features to be described hereinafter, is of a known type with known features which do not form part of this invention. The illustrated fixture includes a lamp body 11 which is mounted on a transformer housing 12 for rotation with respect to the housing 12 about a horizontal axis. Suitable calibration indices 13 may be provided to assist in properly orienting the housing 11 with respect to its rotational axis. The transformer housing 12 is attached to a mounting body 14 and is arranged for rotation with respect to the mounting body 14, about a vertical axis. Calibration indices 15 also can be provided to facilitate proper rotational adjustment about the vertical axis.
The mounting body 14 is of an inverted T-shaped cross sectional configuration, suitable to be received within the downwardly opening recess of a typical bus bar (not shown). A flange 16 at the bottom of the mounting body seats against bottom surfaces of the bus bar.
For mounting the fixture 10 in the bus bar, the mounting body 14 houses an internal rotary element (not shown) carrying electrical contacts 17, 18 and a clamping element 19. The rotary element is fixed to a rotary locking lever 20 located underneath the flange 16. For the initial mounting of the fixture, the lever 20 is rotated at right angles to the mounting body 14, to retract the contacts 17, 18 and the clamping element 19 into the mounting body. After the mounting body is positioned in the bus bar, the lever 20 is rotated to a position parallel with the mounting body, as shown in
After mounting the fixture on the bus bar, the lamp housing 11 is normally adjusted about its respective horizontal and vertical axes to cause light from the fixture to be properly focused on a desired subject area. Typically, there is sufficient friction in the horizontal and vertical rotational connections to enable the housing 11 to remain in an adjusted position. However, over time, various influences such as vibrations, temperature variations, accidental bumping etc., can cause an initial adjusted position to change. Accordingly, manufacturers frequently provide locking devices, such as Allen screws, for tightly locking the elements in their adjusted positions to largely prevent such undesired movements. One such Allen screw is indicated at 21 in
Pursuant to the invention, a locking lever 20 of novel design is provided to enable each lighting fixture to be provided with an Allen key suitable for its components, with the Allen key being inserted and retained in the locking lever so as to be available at all times for securing of the fixture in its adjusted position. With reference to
Locking levers 20 generally are well known devices for use in the mounting of track lighting fixtures and frequently are formed with a bottom opening 29 providing access to an on-off switch (not shown). An associated side recess 30 allows the lever to be rotated to engage or disengage the fixture when the switch is in its “off” position. The locking lever of the invention, however, includes an additional and unique feature for receiving and reliably retaining an Allen key 31. As shown in
Spaced inward from the guide wall 36 is an inner confinement wall 37, which is spaced from the guide wall and defines therewith a confinement space considerably greater than the thickness of the Allen key. In the illustrated and preferred embodiment of the invention, the confinement wall 37 is formed, adjacent to the end wall opening 34 with a short re-entrant wall 38 defining an inwardly facing, open ended recess 39. The recess 39 is arranged to receive one end 40 of a generally J-shaped strip spring 41. The spring 41 includes an elongated stem portion 42, which is received in the confinement space between walls 36, 37, and an arcuate portion 43 configured to pass part way around the socket wall 36. The arcuate portion 43 joins at an apex 44 with a straight portion 45 passing in contact with a facet 46 of the socket wall 26 that lies parallel with the opposite side portions 36, 47 of the wall 24. The straight portion 45 of the spring terminates in an outwardly and rearwardly directed end element 48, which is received in a recess slot 49 on the inside of the wall portion 47.
The spring 41 is assembled with the molded lever body by inserting the spring downwardly into the open top of the lever body, inserting the opposite ends of the spring into their respective confining slots 39, 49. The geometry of the spring 41 is such that, when initially assembled, a portion 50 of the spring, between the straight and arcuate portions 42, 43 lies close to, and preferably bears resiliently against the inner surface of the side wall 36, as shown in
As shown in
As shown in
The key-holding feature of the invention can be incorporated with track lighting fixtures of existing design with minimal cost, consisting of the cost of the spring 41 and its assembly, and minor, one-time mold revisions to accommodate the presence of the spring and to define a recess and an opening for the Allen key.
The new feature has substantial commercial significance in that it makes the overall product substantially more attractive to potential customers. Maintaining the adjustable lighting fixtures in accurate adjustment is a concern of all users thereof, and the improvement of the present invention greatly simplifies such maintenance and, more importantly, makes it more likely that the necessary or desired locking of the fixture adjustment will in fact take place. When “final” adjustments of a fixture have been completed, it is largely assured that the fixture adjustment can and will be properly locked because the required tool is always available to the service person.
It should be understood, of course, that the specific form of the invention herein illustrated and described is intended to be representative only as various changes may be made therein without departing from the clear teachings of the disclosure. Accordingly, reference should be made to the following claims in determining the full scope of the invention.
Number | Name | Date | Kind |
---|---|---|---|
5128847 | Lin et al. | Jul 1992 | A |
5652587 | Liu | Jul 1997 | A |
5702177 | Lin | Dec 1997 | A |