Hinge And Latch Mechanism For Fluorescent Luminaire

Abstract

In a recessed fluorescent luminaire an improved combination hinge and latch mechanism which includes a plurality of inverted L-shaped latch members with raised curved cam portions on the upper ends thereof rotatably secured to the frame of the light-transmitting luminaire door or closure. The luminaire housing includes laterally extending flanges on the side walls adjacent the bottom or open end having apertures therethrough at locations complementary to the locations of the latch members on the door. Curved leaf springs overlie the apertures and are constructed and arranged to cooperate with the curved cam portion of the latch member to releasably retain the latch members in a latched position. When the latches on one side of the luminaire are released the latches on the opposite side serve as hinges through their rotatable connection to the door frame.

Description

BACKGROUND OF THE INVENTION

It has been the practice with respect to lighting equipment and particularly with reference to recessed fluorescent luminaires to provide a separate hinge and latch mechanism for securing the shielding media or refractor-door frame combination in the door opening. In this connection it has been generally the practice to provide specific hardware on one side of the door frame and complementary hardware on one side of the opening to the luminaire housing and another kind of hardware on the other side of the luminaire housing opening to accommodate the respective hinging and latching functions. Consequently, a prefabricated luminaire could only open in a single direction in order to provide access to the interior of the luminaire housing or lamp cavity. When a luminaire is designed to open in only a single direction problems may arise during installation in a building. Lighting fixtures are generally symmetrically located within the building and partitions or other items installed below the fixtures can present obstacles to opening the luminaire which in some cases can be overcome if the luminaire door will open in either direction.

Efforts to permit the door to be hung or hinged and latched from either side of the luminaire housing have resulted in additional openings and/or additional parts on both the door frame and the luminaire housing. These additional openings and parts are objectionable from not only an appearance standpoint but also involve increased cost in both manufacturing operations and materials.

SUMMARY OF THE INVENTION

This invention relates to lighting fixtures and more particularly to a hinge and latch mechanism for a recessed fluorescent luminaire of the type employed in modular ceiling systems of the suspended type.

The interior fluorescent luminaire of this invention provides a clean appearance when viewed from below with a minimum of visible hinge and latch components, the door frame is fully reversible without regard to which side the door is to be hinged or latched, and exhibits a simplicity of operation not heretofore available in an interior recessed fluorescent luminaire. The interior fluorescent luminaire of this invention comprises a housing which includes a top wall and downwardly depending side and end walls which define a lamp cavity having a plurality of lamp sockets and lamps therein. A flange or housing runner extends horizontally from at least one opposite pair of the end or side walls adjacent the bottom thereof and include a plurality of apertures therethrough. A light-transmissive door including a rigid frame closes off the open bottom of the housing and has a plurality of hingedly mounted latch members secured to the frame for rotation with respect thereto and complementarily located to coincide with the apertures in the flanges or housing runners. A curved spring member overlies each of the apertures and is adapted to coact with the head portion of the latch member to releasably retain the latch member in a latched position through the aperture.

BRIEF DESCRIPTION OF THE DRAWING

The many advantages and features of this invention will become more readily apparent and better understood as the following detailed description is considered in connection with the accompany drawing, in which:

FIG. 1 is a bottom plan view of the luminaire of this invention disposed in a modular ceiling system;

FIG. 2 is a sectional view taken along the line II--II of FIG. 1;

FIG. 3 is an enlarged sectional view similar to FIG. 2 with the center portion of the luminaire broken away;

FIG. 4 is a sectional view similar to the right-hand portion of FIG. 3 illustrating the unlatching and latching of the door frame; and

FIG. 5 is a sectional view similar to FIG. 3 illustrating the door of the luminaire in an open position.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now in detail to the drawing wherein like reference characters represent like parts throughout the several views there is illustrated in FIG. 1 a bottom plan view of the luminaire of this invention generally designated 10 as viewed from the room below a modular type drop ceiling employing T-bars or ceiling supports 12 and modular drop-in acoustic ceiling panels 14. The luminaire as seen from the room includes the shielding media or refractor 16 surrounded by a door frame 18, a space 20 and the support frame or runner 22 of the luminaire housing. In the construction illustrated in FIG. 1, the door frame and shielding media present a floating appearance with respect to the luminaire housing support frame 22 because of the space or recess 20 which separates them. The hinge-latch mechanism of this invention facilitates the neat and aesthetically appealing floating door effect of the luminaire illustrated in FIG. 1.

Referring now to FIG. 2 the luminaire housing generally includes a top wall 24 and downwardly depending side and end walls 26 and 28, respectively, which together form and define an optical cavity in which are mounted lamp holders 30 and fluorescent lamps 32. The top wall 24 may also have formed therein a ballast compartment 34. Connected to the housing at the bottom of the side and end walls 26, 28 is a housing support flange or runner generally designated 22 which includes a supporting foot 36, an upstanding member 38 and a lateral mounting flange 40. The lateral mounting flange 40 is a multi-purpose member and may include apertures to permit egress and ingress of conditioned air to the lighted room if it is desired that the lighting fixture be one of the air handling type. The support flange 40 also, in accordance with this invention, and as best illustrated in FIGS. 3-5, serves as a portion of the hinge and latch mechanism of this invention.

The hinge latch mechanism includes three principal parts which include the latch member 42, the latch member retainer 44 and the latch spring 46. The latch member 42 is secured to the edge of the door frame 18 by the latch member retainer 44 which extends through an aperture 43 (FIG. 3) in the latch member and holds the latch member for rotatable movement with respect to the door frame 18 by means of the rod shaped bottom 48 of the latch member. The retainer 44 is secured to the edge of the door frame by suitable means as for example rivets 50.

The upper end or head of the latch member 42 includes a flat hook surface 52 and a sloped or cammed upper surface 54. The latch spring 46, in the form of a curved leaf spring, is secured to the upper side of the support flange 40 and includes a first portion which extends in a direction vertically away from the support flange, a second portion which curves 180.degree. back toward the flange, and a third portion which curves away from the side wall of the housing and downwardly toward the flange with the third portion of the latch spring overlying an aperture 56 in the support flange 40.

A typical luminaire will employ four hinge latch mechanisms, two on each side of the door frame adjacent the corners. Of course, more hinge latch mechanisms can be employed if a longer than normal fixture is desired. When a luminaire is mounted in the ceiling of a newly constructed room the door is attached to the luminaire after the lamps are in place by raising the latch members (on one side of the door) through the complementary apertures 56 in the support flange 40. Coaction between the curved cam surface 54 on the head of the latch member and the third portion of the latch spring will cause the latch member to be forced toward the housing after hook portion 52 has been raised above the upper surface of the support flange 40 causing one side of the luminaire to be latched as illustrated in FIG. 5. Now the door frame and door are hinged to one side of the luminaire housing. In order to close the luminaire door, the door is raised to the closed position and the latch members on the other side of the door frame enter the housing support flange 40 through the apertures 56 on that side of the luminaire and coact with the complementary latch spring 46 to snap the latch closed on the opposite side of the luminaire.

When it is desired to enter the optical cavity to change ballast parts or lamps the door is pushed to one side (either side). This movement forces the latch member against the latch spring until the hook portion 52 completely overlies the aperture 56 at which point the latch member will be ejected from the aperture by the action of the latch spring and the door may be swung to an open position using the latch members on the opposite side of the luminaire as a hinge for the door. As will be apparent, if it is desired to remove the door completely the retained latch members, for example the ones illustrated in the latched position in FIG. 5, are then merely pulled to the left against the action of the latch spring 46 until the hook portion 52 of the latch members on that side overly entirely the apertures, at which point the springs 46 will eject the latch members through the apertures to thereby free the door entirely from the luminaire housing.

As will be apparent from the foregoing the hinge and latch mechanism of this invention supports the refractor or door of a recessed fluorescent luminaire with similar simple components which serve interchangeably as either a securing latch or a hinge for the door frame. Release of the door frame from either side may be simply and quickly accomplished and the door frame may be relatched my merely forcing the head portion of the latch members through the apertures in the support flange of the luminaire housing and the latches will be positively retained in a latched position by the latch springs until such time as positive force is applied to the latch members to move them against the action of the latch springs and free that side of the door from the luminaire housing.

Claims

What is claimed is:

1. In a rectangular luminaire comprising a housing having a top wall and downwardly depending side and end walls defining a lamp cavity, flange portions extending horizontally from the lower end of at least opposite pairs of said side or end walls, and a light transmissive framed door closing off said lamp cavity; the improved hinge and latch mechanism for mounting said door to said housing which hinge and latch mechanism comprises; a plurality of hooked latch members rotatably mounted on said light transmissive framed door, a plurality of complementary apertures in said flange portion each constructed and arranged to receive one of said plurality of hooked latch members therethrough, and curved leaf spring means overlying each of said apertures for releasably retaining said hooked latch member in said aperture.

2. The improved hinge and latch mechanism of claim 1 wherein said hooked latch members include a curved cam surface on the ends thereof and said curved spring means being constructed and arranged to coact with said curved cam surface to force said hooked latch members into a latched relationship with said flange portion when said hooked latch member is inserted through the aperture in said flange portion.

3. The improved latch mechanism according to claim 2 wherein said flange portions extend horizontally and outwardly of each of said side walls.

4. The improved latch mechanism according to claim 3 wherein each of said flange portions have a pair of apertures therethrough adjacent the ends thereof and wherein the pair of hooked latch members associated with the pair of apertures in one of said flanges forms a hinge for said door when the latch members associated with the apertures in said other flange are moved to an unlatched position.

5. The improved latch mechanism according to claim 1 wherein said curved spring means are secured to said flange portions adjacent a side wall of said housing and include a first portion which extends vertically away from said flange portion, a second portion which curves 180.degree. back toward said flange portion and a third portion which curves away from said side wall and downwardly toward said flange portion with said third portion overlying said aperture.

6. The improved latch mechanism according to claim 5 wherein said latch members are substantially in the form of an inverted L with a raised curved cam surface on the top thereof, said curved cam surface coacting with the third portion of said spring means to force said latch means into a latched position when said latch means is inserted through said aperture.

7. An interior fluorescent luminaire comprising:

a housing, including a top wall and downwardly depending side and end walls defining a lamp cavity,

a plurality of lamp sockets within said cavity,

support flange means extending horizontally from at least one opposite pair of said end and side walls,

a light transmissive door including a rigid frame closing off the open bottom of said housing,

a plurality of hingedly mounted latch members secured to said rigid frame for rotation with respect thereto,

a plurality of apertures in said flange means constructed and arranged to receive said latch means therethrough, and

curved leaf spring means overlying each of said apertures and adapted to coact with a portion of said latch means to releasably retain said latch means in a latched position.

8. A luminaire according to claim 7 wherein said curved spring means is secured to said flange adjacent said side wall and includes a first portion which extends vertically away from said flange, a second portion which curves 180.degree. back toward said flange and a third portion which curves away from said side wall and downwardly toward said flange with said third portion overlying said aperture.

9. A luminaire according to claim 8 wherein said latch member is substantially in the form of an inverted L with a raised curved cam surface on the top thereof, said curved cam surface coacting with the third portion of said spring means to force said latch means into a latched position when said latch means is inserted through said aperture.