An annunciator is provided. The annunciator includes a parabolic reflector formed from an insulating material, a reflective layer of metal disposed on a surface of the reflector, a high voltage strobe lamp disposed at a focal point of the reflector with a set of conductors of the strobe lamp extending through a center aperture of the reflector and a portion of the reflector proximate the aperture devoid of metallization.

FIELD OF THE INVENTION

The field of the invention relates to strobe lamps and more particularly to strobe lamps for security system annunciators.

BACKGROUND OF THE INVENTION

Annunciators can often serve a very important purpose in security systems. For example, security lapses can often represent risk to human life. Annunciators can function to notify occupants of the existence of the lapse as well the type of lapse.

Annunciators can be audible or visual or both. However, in order to accommodate persons with visual or auditory impairments, annunciators for security systems usually include both audible and visual alerting devices.

In order to reduce costs, security systems are often provided with a number of annunciators, sensors and access control devices interconnected with a control panel via radio frequency links. In some cases, these devices are battery powered.

In order to extend battery life, annunciators used in such systems must be constructed to use as little battery energy as possible. One solution to this problem has been to use strobe lights for visual annunciation.

In general, a strobe light consumes significantly less energy than a conventional fluorescent or incandescent light source. The low energy consumption results from the low cycle time of a strobe light and also because of the brilliant contrast produced when the strobed light flash occurs.

In order to further reduce energy consumption, strobe lights are also often used with collimating reflectors that collimate the light from the strobe into a light diffusing lens. Collimating the light from the strobe onto a diffusing lens causes the light source to appear much larger than the actual light emitting source presented by the strobe light. Because of the importance of strobe lights in security systems, there is a need for better methods of constructing such devices.

DETAILED DESCRIPTION OF AN ILLUSTRATED EMBODIMENT OF THE INVENTION

FIG. 1depicts a security system50shown generally in accordance with an illustrated embodiment of the invention. The alarm system50may include an alarm panel48, one or more sensors52and an alarm annunciator10. Under one illustrated embodiment, the alarm system50may be a fire alarm system. In this embodiment, the sensors52may be smoke or flame sensors.

In the event of a fire, the one or more sensors52may enter an activated state and send an alarm signal54to the alarm panel48. The alarm panel48may respond by sending alarm signal56to the annunciator10activating the annunciator10.

The annunciator10may include an audible transducer assembly12and a visual transducer assembly14. The visual transducer assembly14includes a diffusion lens16, a shaped reflector18and a strobe light20.FIG. 2shows a close-up view of the annunciator10with the diffusion lens16removed.FIG. 3shows a close-up view of the annunciator10ofFIG. 1with the cover22also removed.

As shown inFIG. 3, the reflector18and strobe light20are supported by a printed circuit board (PCB)24. Similarly, the PCB24supports and is attached to the cover22.

Included on the PCB24is a pulsing circuit58that periodically (e.g., every 2 seconds, every 5 seconds, etc.) applies a strobe voltage (i.e., high voltage pulse)21to the strobe light20. The pulsing circuit may be battery powered under control of an activating signal from the alarm panel48.

The reflector18functions to receive incident light from the strobe lamp20and to reflect incident light in accordance with the design objectives of the annunciator10. For example, the reflector18may have a modified parabolic shape in two or three dimensions in order to direct incident light outwards from the reflector18parallel to a longitudinal axis28of the strobe light20and into the diffusion lens16.

The reflector18may have a parabolic shape centered on the base of the strobe lamp20with a focal point of the parabola centered at a midpoint along the length of the strobe light20. Alternatively, the parabolic shape may be modified to reflect the fact that the strobe light20generates light along the finite length of a gas discharge tube and not from the point source that would otherwise define a parabola.

The reflector18may be supported and/or attached to the PCB24at a number of locations. For example, a post30on opposing ends of reflector18may be attached to the PCB24. The reflector18may also be attached via a set of apertures32,34extending through the center of the reflector18. In this case, an insulating bushing36,38may extend through the reflector18and where a conductor of the flash tube20and second conductor26may extend through the bushings36,38to form an electrical connection with a respective set of conductors on the PCB24.

A body40of the reflector18may be fabricated of an appropriate insulating structural material (e.g., plastic, nylon, etc.). An upper surface of the reflector18is coated with a metalized layer42of an appropriate reflective material (e.g., chrome).

One feature of the reflector18is an insulation stand-off region44that is devoid of the metallic coating42. The region44surrounds the electrical feedthrough apertures32,34of the strobe20. The stand-off region44may have an appropriate width (e.g., ⅛ inch, ¼ inch, etc.)46between the feedthrough conductors and metalized layer42to prevent electrical flashover from the electrically charged conductors of the strobe20to the metalized layer42when the strobe20is fired or otherwise activated. The width may be based upon the type of strobe20. For example, if the strobe20is a zenon tube, then the width may be ⅛ inch or more depending upon the voltage required and upon the type of gas used in the gas discharge tube of the strobe20.

The stand-off region44may be created using any of a number of different methods. Under a first method, the region44may be coated with a protective coating before a plating process that adds the metalized layer42to the body. After plating, the protective layer is removed. Alternatively, the entire upper surface of the body42may be plated and then masked for removal of the plating in the stand-off region by etching.

Under still another embodiment, the region44may be masked before a plating process that adds the metalized layer42to the masked body. After plating, the mask is removed and reused on the next reflector18.

The stand-off region44simplifies the construction of strobe lamps. By providing the stand-off region44, the bushings36,38can be considerably smaller with a lower flash-over rating.