Abstract:
A retractable light fixture apparatus has a fixture housing for mounting in or to the wall of a building or under the eave of a building. A lamp housing and lamp is hinged to the fixture housing and is movable from a closed to an open position by an electric motor and from an open to a closed position by a gas spring. An electric brake holds the lamp housing in an open position against the gas spring whenever electric power is applied thereto.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This invention relates to light fixtures and particularly to a wall mounted light fixture having a lamp movable between an open and a closed position. 
         [0002]    The use of exterior lighting for residential and commercial applications in the U.S. and other parts of the world is extremely popular. Exterior lighting is used for safety, recreational, aesthetics, and decorative reasons. Site lighting and perimeter lighting is standard practice for all new construction. Many municipalities have building codes that require a minimum light level for commercial retail buildings. One of the most common types of light fixtures used in exterior site and perimeter applications is the wall mounted style also known as “Wallpacks”. There are currently two basic configurations of wallpack light fixtures. There is the surface mounted and the semi-recessed mounted. Although both styles of light fixtures can illuminate the perimeter or site of a building, neither have all the advantages of a completely sealed and fully recessed retractable light fixture. The fully retractable light fixture blends into the architecture much better than a surface mount/box style lighting fixture. Surface mounted fixtures are often unsightly and can be exposed to vandalism during the daylight hours. The retractable light fixture is completely closed and sealed during the daylight hours which provides a better look and vandal resistant benefits. The retractable light fixture can also produce better photometrics than a semi-recessed fixture because the lamp compartment retracts completely out of its recessed housing. Semi-recessed wallpacks typically shine the light straight out which often produces ineffective lighting. Furthermore, semi-recessed light fixtures have their lenses completely exposed during daylight hours which is unsightly and subject to damage. 
         [0003]    In my prior art U.S. Pat. Nos. 5,075,834 and 5,124,902 I provide retractable light fixtures mounted in a housing positioned in the ground and having a cover with a solenoid actuated lamp to move a retractable lamp from a retracted to an extended position. A retractable reading light is shown in the Alie et al. U.S. Pat. No. 4,567,547 for an air and light utility assembly. Retractable vehicle lamp assemblies can be seen in the Yukimoto et al. U.S. Pat. No. 4,630,179 for a retractable lamp which includes a lamp pivotally held on an axis to be extended and retracted into a housing and in the similar Fukura et al., U.S. Pat. No. 4,785,382, for a retractable lamp device for vehicles. The Trenkler U.S. Pat. No. 4,121,478 is a retractable headlamp for motor vehicles while the Matsushiro U.S. Pat. No. 4,320,441 is a retractable headlight for a radio controlled toy vehicle. 
         [0004]    The present invention is directed towards a retractable light fixture which can be mounted onto the side of an interior or exterior wall or in a wall, such as between the studs of a building wall, or in the soffit of a roof. The retractable light fixture allows the lamp to be opened by actuating a switch to apply power to the light fixture. Switching on the electric power both opens the lamp housing, turns on the lamp, and then holds the lamp in place with an electromagnetic brake. Switching off the power allows the electromagnetic brake to disengage, turns off the lamp and allows the housing to close. 
       SUMMARY OF THE INVENTION 
       [0005]    A retractable light fixture apparatus has a fixture housing for mounting to or in an interior or exterior wall of a building or in the soffit of a building eave. A lamp housing is hinged to the fixture housing and is movable between closed and opened positions and contains an electric lamp therein. An AC electric motor drive is in the lamp housing and is operatively attached to the fixture housing to move the lamp housing from the closed to the open position. Biasing means, such as a gas spring, biases the lamp housing from its open to its closed position when switching off the power to the light fixture. An electric power source is connected to the electric motor to actuate the electric motor. An electromagnetic brake holds the lamp housing in an open position against the air spring and operates by cutting off the AC electric power to the electric motor and applying a DC electric source to the motor. A microswitch connects the electric power source to the electric motor in a first position and deactivates the electric motor in a second position and at the same time connects the DC electric power to the electric motor to lock the motor shaft. The electromagnetic brake merely applies a DC voltage to the AC motor which locks the AC motor shaft and the electric lamp in its open position. Thus, an AC electric light fixture actuates an AC electric motor upon receiving electric power to open the lamp housing and then holds the lamp housing open with the electro-magnetic brake and with the lamp turned on until electric power to the electric fixture is turned off. The fixture housing has a center open portion adapted for the lamp housing to fit thereinto in a closed position. The light fixture includes a gear box operatively connected-to the electric motor having an output shaft therefrom. A microswitch is moved from the first position to the second position by a switch arm aligned with a cam on the gear box output shaft for moving the switch between the first position and a second position by the rotation of the output shaft driving the cam against the switch arm. The gear box output shaft is connected to the fixture housing with a gas cylinder which rotates and closes the lamp housing when the electric power is turned off. The lamp housing opening can be varied by adjusting a coupling to the gear box output shaft to vary the position on the shaft relative to the cam. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Other objects, features, and advantages of the present invention will be apparent from the written description and the drawings in which: 
           [0007]      FIG. 1  is a perspective view of a retractable light fixture in accordance with the present invention having the lamp housing in a closed position; 
           [0008]      FIG. 2  is a perspective view of a retractable light fixture of  FIG. 1  having the lamp housing in an open position; 
           [0009]      FIG. 3  is a perspective view of a retractable light fixture of  FIGS. 1 and 2  having a lamp housing open to a different position; 
           [0010]      FIG. 4  is a perspective view of a drive system for opening the light fixtures of  FIGS. 1 through 3 ; and 
           [0011]      FIG. 5  is a block diagram of the operation of the circuitry of the light fixtures of  FIGS. 1 through 3 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0012]    Referring to the drawings and especially to  FIGS. 1 through 3 , a light fixture  10  has a fixture housing  11  and a lamp housing  12  and is shown with a wiring J-box  13 . The lamp housing  12  is shown in the closed position in the main fixture housing  11  in  FIG. 1  and in an open position in  FIGS. 2 and 3 . The fixture housing  11  has an open space  14  therein. The lamp housing while housing  12  is shown open to a higher position in  FIG. 3  so that you can see the lamp housing lens  15  having a lamp  16  mounted therein. The fixture  10  is ideally suited for placing on the side of a wall or, in the embodiment illustrated, built into a wall in which the sides of the housing  11  will fit between the spacing of the studs in a building wall. The lamp fixture can also fit into the soffit of the eave of a building. The lamp housing  12  is readily adjustable to open to any angle desired, such as that shown in  FIG. 2  and again in  FIG. 3 . 
         [0013]    The opening and closing of the lamp housing  12  is better illustrated in connection with  FIGS. 2 ,  3  and  4  in which a gas spring  17  has a gas cylinder  18  and an extending rod  20 . Extending rod  20  has a coupling  21  for attaching to the main fixture housing  11  while the gas cylinder  18  is connected to a spring coupling  22  which is attached to a gear motor shaft  23  extending from the gear box  24  and electric motor  25 . The gas spring coupling  22  can have its position on the shaft  23  adjusted by loosening a set screw  26  and rotating it to two different positions relative to the shaft  23 . The cylinder  18  is connected to the spring coupling by a flexible connections so that the rotation of the coupling  22  rotates and pulls the gas spring  17  to different positions, depending upon where the coupling  22  is locked to the shaft  23 . 
         [0014]    Gear box  24  shaft  23  has a cam  27  attached thereto and a microswitch  28  is attached to the side of a gear box  24 . Microswitch  28  has a switch arm  30  extending therefrom leaning against the shaft  23 . As the motor  25  is powered to turn the gear box  24  shaft  23 , it rotates to a position where the cam  27  hits the microswitch arm  30  to activate the microswitch. The gear motor armature  31  is seen protruding from the AC electric motor  25 . 
         [0015]    In operation, the AC electric motor  25  is actuated by turning on the electric power with a switch or by a timer clock or a photocell or motion detector as desired which starts the shaft  23  rotating until the cam  27  actuates the microswitch arm  30  and actuates the microswitch  28  which cuts off the power to the electric motor  25  with the shaft  23  in the position determined by of the cam  27 . This opens the lamp housing  12  from a closed position, as seen in  FIG. 1 , to an open position, as seen in  FIGS. 2  or  3 , against the gas spring biasing means  17 . When the electric power to the fixture is cut, the gas spring  17  pulls the spring coupling  22  and shaft  23  to pull against the lamp housing  12  to close the lamp housing. The lamp fixture of the present invention includes an electromagnetic brake, as hereinafter described, which locks the shaft  23  against movement to prevent the lamp housing from closing once it reaches its open position and the lamp is turned on. 
         [0016]    Turning to  FIG. 5 , a block diagram of the circuit of the present light fixture is illustrated in which a source of AC electric power  33  is connected through a line  32  to a microswitch  28 . The microswitch  28  is normally in a normally closed position, as illustrated, and directs the hot line  32  of the AC power through the line  34  to the gear motor  25 . The hot line  35  is also connected to the lamp  16  to activate the lamp. Common line  36  is connected to the lamp and to the gear motor  25 . An AC motor  25  rotates the shaft  23  until the cam  27  of  FIG. 4  hits the microswitch  28  switching the microswitch  28  to the normally open position thereby cutting off the AC power from the line  34  to the gear motor  25 . Then the AC power in line  32  is switched from the AC electric motor  25  through a line  37  to a DC power supply  38  which immediately puts a DC power source through the line  40  directly to the gear motor  25 . Gear motor  25  is an AC motor in which AC power has been disconnected and a DC voltage applied thereto. The AC motor is locked up by the DC voltage and forms an electromagnetic brake. The shaft  23  is locked in position which has the lamp housing in an open position. The DC power supply  38  stays on as long as there is AC power and the power source  31  is connected through the microswitch  28  which also maintains the lamp  16  turned on. The power supply from  33  is switched with a manual switch or a photocell or a timer or the like to turn the power off and disconnect the lamp  16  and the DC power source  38  which releases the gear motor  25  armature  31  from the shaft  23  allowing the gear springs  17  to return the lamp housing  12  back to its closed position until the AC power is again switched on. 
         [0017]    Thus, the sequence of events would be where there is no power through the AC power switch  33  and the lamp housing is closed, as in  FIG. 1 . When the switch  33  is turned on, the gear motor and lamp power are turned on and the gear motor turns until the microswitch  28  is activated. The microswitch turns off the AC power to the gear motor  25  and turns on the power to the DC power supply  38 , which applies a DC power to the gear motor  25  and freezes the gear motor armature into an open position for the lamp fixture. When the switch  33  is turned off to disconnect the AC power, the unit closes under the gas spring and the lamp is turned off. 
         [0018]    It should be clear that a lamp fixture has been provided which is merely switched on or off to open the lamp fixture, turn on the lamp, and to hold it in an open position until it is closed by a biasing means. A biasing means can be a gas spring, as illustrated, or a torsion spring or by the gravity of the lamp housing. However, the use of a gas spring, or the like, with an easily adjustable coupling to a gear box output shaft allows for a quick adjustment to different positions of the lamp housing opening. However, it should be clear that other forms and embodiments are considered within the scope of the present invention and the forms shown are to be considered illustrative rather than restrictive.