US1843558A - Filter device for floodlights - Google Patents

Description

Feb. 2, 1932. J. A HOEVELER FILTER DEVICE FOR FLOODLIGHTS Filed Oct. 7, 1929 Patented Feb. 2, 1932 PATENT OFFECE JOHN A. HOEVELER,,OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR I'O P IT'I'SBUBGI-I REFLECTOR COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF NEVJ JERSEY I Application filed October 7,

My invention relates to illuminatingdevices and, in particular, to devices utilized for purposes of color fioodlighting. Novel features of my invention residevin the means provided for supporting a color filtering de-' vice in cooperation with a reflector bowl,and also in the means for ventilating the color filtering device without permitting the escape of an unfilteredor white beam of light from the ventilating opening.

It has been the practice formerly to support the color filtering device used in connection with floodli 'hting lamps by meansof a pair of resilient gripping rings to which said device, which customarily takes the form of a, cap of colored glass partially spherical in shape, is secured. The rings are designed to engage the sides of the spherical portion of an incandescent electric lamp bulb in the. manner in which the shades of small table lamps are adapted to be supported from the incandescent lamp bulbs thereof. Because of the considerable temperatures attained by the high power lamps which it is customary to employ in fioodlighting installations, however, this method of supporting a color cap'has been foundiunsuccessful. The portions of the lamp bulb engaged by the gripping rings have, in numerous instances, been melted by'the heat developed by the lamp filament with the consequent destruction of the bulb and failure of the lamp. The color cap itself complicates the problem of cooling the lamp since the types heretofore in use tend to prevent the flow of cooling air currents over the surface of the incandescent lamp bulb.

I avoid the difiiculties encountered in connection with the devices of the prior art by providing a supporting means for a color filtering device which is adapted to engage the lamp housing instead of the lamp bulb itself. Further provision is made for ventilating the lamp chamber formed by the color filtering device in cooperation with the reflector bowl.

A present preferred embodiment of my invention is illustrated in the accompanying drawings in'which, V

Figure 1 is a partial sectional View of a FILTER DEVTCE FOR FLOODLIGHTS 1929. SeriaI No. 397,835.

floodlighting unit embodying my invention; Figures 2 and 3' are plan views of details thereof; and

I Figure 4 is a perspective view of an additional detail. 7

Referring particularly to Figure 1, the

preferred embodiment of my invention con sists of a. metal drum, partially illustrated at 10. The drum 10 is provided with a suitable metal rim 11 having an inwardly flarin portion 12. A reflector bowl is illustrated at 13 and is seated in the inwardly flaring portion 12 of the rim 11. A layer of felt 1 1 is provided between the bowl 13 and the rim 11 to minimize possible breakage of the forannular channel 16 in which a color filter-' ing device 17 in the form of a partially spherical glass cap pervious to light of the desired color, hereinafter for brevity referred to color cap, is seated. The color cap 17 and the lower portion of the reflector bowl constitute an enclosure or chamber for the lamp bulb 15.

In order to prevent damage to the incandescent lamp bulb, reflector bowl, or color cap as a result of the heat accumulated in the lamp chambenl provide a central opening in the top of the cap 17. 'I also provide a closure for this opening which permits of easy ventilation of the lamp chamber and, at the same time, protects the lamp bulb, as wellas preventing the projection of a beam of white light from the lamp 15. i

The closure for the opening in the top of .the'color cap 17 comprises anapertured disc 18, illustrated in detail in Figure 3, having central and peripheral openings 19 and 20. The disc 18 is provided with a downwardly turned flange 21 which is adapted to be received within the opening in the color cap 17. The disc 18 is also provided with an up wardly'turned flange 22 which is designed to receive a cooperating downwardly disposed flange 23 of a dished cover 24:. The disc 18 and the cover 24: are adapted to be secured to each other, and to the color cap 17 by a transverse clamping strap 25, illustratel in detail in Figure l, and a clamping bolt 26. The clamping strap 25 is provided with extensions 27 for engagement with the inner wall of the cap 17.

In order to secure the color cap 17 and its ventilating closure to the housing 10, a second transverse ciamping strap 28 is provided. The strap 28 is illustrated in detail in Figure 2 and has a slot 29 at each end which is adapted to be engaged by a thumb screw 30 threaded o a tapped hole in the rim 11. The clamping bolt 26 also passes through a central hole 31 in th strap 28 so that, when ass mbled, the ire device comprising the housing, reflectw, color cap and ventilating closure constitute a unitary structure. The VZl-liOllS parts are rigidly held in their respec: tive positions u' l nout contact between the lamp bulb 15 and the reflector 13 or the color can 17. lhe latter, in addition, is provided with ventilating device which serves "to perniit the passage of a current of cooling air through the lamp chamber. The clamping strap 28 is bent, as indicated by the dot-anddash lines of Figure 1, so as to exert a spring pressure on the color cap 17. V

W l ile I ha c illustrated and described but a single preferred embodiment ofiny invention, it will be obvious to those skilled in the art that modification and alterations therein may prove desirable. lfor that reason, it is not my 1 en'ion to be limited to theembodiinent herein disclosed except as necessitated by the terms of the appended claims which are relied upon to define the scope of my invention.

1. In a lighting unit, the combinatlon w th a housing and a reflector mounted thereln, of a color cap within said reflector cooperating therewith to form a lamp chamber, an opening in the top of said cap and means for covering the opening comprlsing a disc overlying said opening provlded w1th central and circumferential apertures, a cover for said disc, a clamping strap Within the cap and extending across the openingthereln, means for securing said cover to said strap, a second clamping strap extending across said housing and secured thereto at its ends, and to said cover.

2. An illumination device comprislng a casing, a reflecting bowl therein and a color cap superposed on said bowl, an opening in said cap and a closure therefor comprising a venting disc, a cover thereover, clamping straps within and without the cap, bridging the opening in the cap and the casing, respectively, means for securing said straps and cover together and for fastening the ends of the outer strap to said casing.

3. In a lighting unit including a casing and a reflector therein, a color cap cooperating with said reflector and means for ventilating the enclosure formed thereby comprising an opening in the cap and a venting closure therefor constituted by a perforated disc, a cover thereon, a clamping strap within said cap, bridging the opening therein, and means for clamping said cover to said strap.

1. An illumination device comprising a housing, a reflector in the housing and a color cap engaging said reflector, a transverse clamping member secured to said housing for engaging said cap, and a vented connection between said cap and said member.

5. The combination with a housing for an illuminating device and a reflector mounted therein, of a color cap overlying at least a portion of said reflector, a ventilator in said cap, and a clamping strap bridging said reflector and secured to said housing and ventilator for maintaining said cap thereon.

6. A ventilating device for lamp enclosures having an opening therein, comprising a disc provided with central and peripheral ventilating apertures, adapted to fit over said opening and extend therebeyond, a cover for overlying said disc without closing said apertures, a clamping member engaging the inner edge of the opening in the enclosure, and means'for securing said cover to said clamping member.

7. The combination with a cylindrical casing, a reflector seated in one end thereof, and a color cap with a central opening engaging said reflector, of a ventilating closure for said opening and a strap extending across said casing and secured thereto and to said closure for holding said cap in position.

In testimony whereof I have hereunto set my hand.

JOHN A. HOEVELER.

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