The invention relates to the field of specialty lighting and more particularly to specialty lighting fixtures useful for theater and commercial lighting applications, where the fixtures frequently incorporate accessory elements such as distributing lenses, color discs and the like, and especially where there may be a need or desire to change the accessories from time to time.
Specialized lighting fixtures, such as for theaters, museums, galleries, exhibits, etc. frequently employ accessory elements, such as color filters, conditioners, beam spreading or concentrating lenses, and the like to achieve desired lighting effects. In many such circumstances, it is necessary or desirable to change the accessories from time to time to accommodate changes in the lighting requirements. As set forth in a related U.S. Pat. No. 6,942,368, to Kenneth M. Kane et al, it is advantageous to utilize a removable cartridge to hold the desired accessories. This allows the accessories to be installed in a cartridge in the proper order, at a work bench or other convenient location, after which the cartridge can be quickly and easily inserted into the lighting fixture. This minimizes the time and effort required of a service man while working high on a ladder.
Inasmuch as a given lighting fixture may typically utilize from one to three accessories, and occasionally none, there was a need to be able to optimally position the accessories with respect to the light source, in order to enhance the efficiency of the lighting and the effectiveness of the accessories.
The present invention is directed to an improved form of accessory cartridge, which can be replaceably installed in a lighting fixture and which automatically results in a desired positioning of the accessories relative to the light source, regardless of the number of accessories installed in the cartridge. To this end, the accessory cartridge of the invention comprises two telescopically joined cartridge members. An outer member is of a size and shape to be received in a fixed position at the open end of the lighting fixture. An inner member is received within the outer member and is telescopically movable with respect thereto over a fixed range of axial movement. Detent arrangements are provided to retain the two members in any position with the intended axial range, unless intentionally displaced.
In the preferred and illustrated embodiment of the invention, the inner cartridge member is of a size and shape to receive one or more, usually but not necessarily up to a maximum of three, accessory elements. Typically, the accessory elements are flat discs which, if more than one is used, are arranged in an axial stack, one on top of the next. After the cartridge is loaded with the desired accessories, the inner and outer members are moved into an axially extended configuration in which the accessories are elevated in relation to the bottom of the cartridge.
When the loaded cartridge is partially inserted into the open end of the fixture, the uppermost accessory disc engages a fixed stop element within the fixture housing. Thereafter, as the outer cartridge member is moved deeper into the housing, the inner cartridge member is held by the stop element and retains a desired predetermined position relative to the light source while the outer cartridge member is being fully seated in the fixture. To advantage, the stop element is the open end of a reflector which surrounds the light source and directs its light in a desired manner from the fixture housing.
For a more complete understanding of the above and other features and advantages of the invention, reference should be made to the following detailed description of a preferred embodiment of the invention and to the accompanying drawings.
Referring to the drawings, and initially to
Pursuant to the invention, a novel form of accessory cartridge 30 is provided, which is insertable into the open lower end 31 of the fixture housing 21, for retaining on or more accessory discs 32. In the illustrated example, the cartridge 30 has the capacity to receive up to three accessory discs (or none, if desired). The cartridge 30 is comprised of an outer member 33, which is adapted to be received and retained in the open end of the fixture housing 21, and an inner member 34, which is movably retained within the outer member for a limited extent of telescopic movement.
In the illustrated form of the invention the outer cartridge member 33 includes a lower portion 35 and an upper portion 36. The lower portion 35 is of cylindrical form and is provided with a flange 37 at its lower end. As shown in
Suitable means are provided for retaining the outer cartridge member 33 within the fixture housing 21 after installation. In the illustrated embodiment, such means can be in the form of a plurality of retainer springs 39, which are riveted or otherwise secured to the upper portion 36 of the cartridge member 33 and extend outward and downward therefrom as shown in
In the illustrated embodiment of the invention, the inner cartridge member 34 is of generally cylindrical form and has an outer diameter very slightly smaller than the inside diameter of the upper portion 36 of the outer member 33. The arrangement is such that the inner member 34 can be telescopically adjusted axially with respect to the outer member. The inner cartridge member 34 is comprised of upper and lower portions 40, 41 which are connected in fixed relation by circumferentially separated spacer elements 42. In the illustrated arrangement, there are three such spacer elements 42 which are widely separated by openings 43 to accommodate the circulation of air within the fixture.
Each of the spacer elements 42 is provided externally with one or more projections 44, which extend radially outward and are adapted to engage the bottom edge 45 of the upper portion 36 of the outer cartridge member. This serves to define an upper limit of extending telescopic movement of the inner cartridge member 34 relative to the outer member. A lower limit of retracting telescopic movement is provided by means of upward extensions 46, which are preferably although not necessarily aligned with the spacer elements 42. At their upper extremities, the upward extensions are formed with flanges 47 extending radially outward and overhanging the upper edge 48 of the upper portion 36 of the outer cartridge member 33. When the inner cartridge member 34 is moved telescopically downward toward a retracted position, the flanges 47 will engage the upper edge 48 when the retracted limit position is reached. The upward extensions 46 have sufficient flexibility to be displaced radially inward when the inner cartridge member 34 is initially assembled with the outer member 33. In this respect, the upper surfaces of the flanges are angled such that the extensions 46 tend to be cammed inwardly during the initial assembly of the two cartridge members 33, 34.
The lower portion 41 of the inner cartridge member is formed with an inwardly projecting flange 49 arranged to support outer edge portions of an accessory disc 32 (
When an accessory disc is inserted into the inner cartridge member 34, it is initially engaged by the tapered upper end portions 53 of the ribs 52 and must be pushed downwardly with enough pressure to displace the tongues 51 and ribs 52 radially outward, as shown in
When accessory discs are loaded into the cartridge, the initial loading is followed by telescopically extending the inner cartridge member 34 with respect to the outer cartridge member 33, preferably until the projections 44 engage the edge 45 of the outer cartridge member 33, setting the limit position of the inner member 34 in an extending direction.
Upon a partial insertion of a loaded cartridge into the end of the fixture housing 21, the uppermost accessory disc 32 of a stack (whether a single disc or a stack or two or three) is engaged by the lower end edge 54 of the reflector 24. The accessory discs, and the inner cartridge member 34 are thus stopped and prevented from moving as the outer cartridge member 33 continues to be inserted upwardly into the housing, until the flange 37 engages the end of the housing. After the insertion, the outer cartridge member is held in position in the fixture housing 21 by the retainer springs 39, and the disc stack is held in fixed position against the end of the reflector. Placement of the accessory discs 32 a known, fixed distance from the light source 22 assures optimum efficiencies from the light source and also uniform and optimized output from the accessories.
In the illustration of
In order to hold the inner cartridge member 34 in whatever position it assumes after insertion of the outer cartridge member 33 into the fixture housing, a detent arrangement is provided which will retain the inner member in position with respect to the outer member, unless intentionally changed. To this end, the outer surface of upper portion 40 on the inner cartridge member is formed with a plurality of circumferential detent grooves 55 engageable by detent projections 56 extending inwardly from upper and/or lower sets of flexible tongues 57, 58 formed in the wall of the upper portion 36 of the outer cartridge member 33 (
The new articulating accessory cartridge of the invention makes it easy and reliable to position the accessory discs, regardless of number thereof, in an optimum relation to the light source, such that optimum and reproducible lighting effects may be achieved. Changing of accessory discs in the cartridge is a simple matter of pushing them upwardly out of the inner cartridge member 34, for removal, and downwardly for loading. The uppermost disc is engaged by the retaining tongues 50 to retain all of the installed accessory discs in a tight stack against the lower flange 49, and installation of the loaded cartridge into a fixture housing automatically telescopically repositions the inner cartridge 34 member as necessary to locate the accessories mounted therein in optimal relation to the light source.
It should be understood, or course that the particular embodiments of the invention herein illustrated and described are intended to be representative of the invention but not limiting thereof. Accordingly, reference should be made to the following appended claims in determining the full scope of the invention.
Number | Name | Date | Kind |
---|---|---|---|
6942368 | Kane et al. | Sep 2005 | B1 |
7988336 | Harbers et al. | Aug 2011 | B1 |