Abstract: A backup alarm for producing an audible warning signal which warbles or beeps, at selected audible output power (Db) levels includes a computer which drives a speaker by switching drive voltage to the speaker with above audible, high frequency pulses in packets repetitive at audible frequency. The high frequency pulses are pulse width modulated at different ratios selected from tables in memory of the computer in accordance with the voltage from a battery power source which provides the drive voltage so that the audible output power remains constant at the selected level over a wide range of power source voltage. By providing for warning/alarm signal generation by means of an operating system which provides both high, above audible frequency and audible frequency switching, power conservation and warning signal output power control are accomplished without interference.

Abstract: A reflex speaker which provides an acoustic signal generator for acoustic alarm signals is captured in a housing through which the acoustic signals project via ports at the exit end of the housing. The housing defines a compartment at the exit end with an opening which is covered so that the acoustic signals project out of the exit end around the compartment. The cover may be a transparent cover which provides a lens through which optical signals generated by optics in the compartment provided by either LEDs to provide an optical warning signal, or a video camera, such as a CCD, which responds to visual signals as from hazards at the rear of the vehicle.

Abstract: An LED beacon has a plurality of LED's mounted on opposite sides of a square post in the same horizontal plane. Each LED projects the light there from through an optical system. The optical system is provided by a collimating lens, preferably a cylindrical fresnel lens and a condensing, coupling lens for each LED also mounted on the post. The optical system provides enhanced illumination distributed in a cylindrical beam emanating from the fresnel collimating lens. The illumination is enhanced in that the condensing lens shifts the focus of the collimating lens to the location of the LEDs. Nominally, the fresnel collimating lens is focused at the center of the array of LEDs (the middle of the post).

Abstract: A multimode controller for LED light sources, especially sources in warning lights, such as light bars, provides for a temporary increase in brightness from the LEDs by providing a burst mode, in addition to a flashing mode and a continuous mode. The modes are carried out by programming a microprocessor which receives signals from control switches, which may be pressed and released. The programming precludes the burst mode to continue for longer than a predetermined time thereby ensuring that the power does not exceed the LEDs damage threshold characteristic. The controller thereby provides for temporary bursting to make visible the region in front of or around an emergency vehicle for a short period of time without the need for light sources dedicated solely to the high intensity brightness mode of operation of a warning light system.

Abstract: A loudspeaker for projecting siren and other warning signals which is compact to facilitate installation in emergency vehicles, and which provides a horn projector in the compact space. The loudspeaker has a support in which an electrically driven driver unit is mounted. A chamber providing a plurality of cyclonic or spiral paths for sound from the speaker is located at one end of the support as by being connected to the support or being a part thereof. The support has a plurality of passageways for sound from each of the paths to exit ports at an end of the support opposite to the end thereof attached to or having the chamber. The cyclonic paths and the passageways are of like length and taper so that the sound from the exit ports combined in reinforcing relationship and projects outwardly from the exit port end of the support. The support provides a recombiner for the sound propagating along the cyclonic paths and passageways to provide the effect of a long horn in the compact space.

Abstract: An interior light bar adapted to be installed on the rear deck of a vehicle for projecting light out of the rear window. The light bar has a pair of projection units each having a housing and each slidably mounted on a rail which extends through the housings from an end thereof and along a rear, closed side. The units each contain light emitters which project the light out of the open side of the units. The units are assembled with a selected separation distance so that the ends through which the rail extends are essentially in contact or sufficiently spread apart to clear a brake light assembly on the rear deck or even further apart so as to provide a wide width of illumination out of the rear window from the light bar. The rail may be channel which provides a conduit for wiring from the light emitter units. Fasteners which connect the housings and the rail into an integrated assembly extend through the closed side of the housing.

Abstract: Apparatus for controlling visible and audible warning signals, particularly signals from light bars, traffic director lighting, and siren and public address outputs for police and emergency vehicle applications, is provided in a single unit. Mounted in a chassis of the unit in layered relationship are a siren board and a relay board. The siren board contains amplifier and associated circuitry for generating and amplifying siren signals, and for providing microphone signals and signals from a 2-way radio of the vehicle, to a speaker which projects these audible signals for warning of and controlling emergency conditions. The relay board contains circuitry for switching power from the vehicle battery to the traffic director lighting and warning lighting (as may be provided by light bars) mounted on or in the vehicle. A microcontroller switches the lighting to the selected lighting units via relays on the board.

Abstract: A sub-assembly for a light-projecting module has an array of LEDs mounted on a circuit board potted in a tray at the bottom thereof by a solidified body of potting material. The body of potting material and the tray are heat-conductive and serve to dissipate heat generated by the LEDs. A light-emitting module includes the sub-assembly and a reflector. The reflector has a base which is assembled in heat-conductive relationship with the tray, so as to facilitate dissipation of heat generated by the LEDs. The reflector is a parabolic reflector which collects light from the LEDs and projects the light as a beam. The reflector contains an optical element for concentrating or diffusing the light projected from the module. The module may be assembled in a housing having an opening through which the light projects so as to provide a light bar suitable for mounting on the dash or windshield of a vehicle.

Abstract: A shock absorbing mounting for a rotating warning light for a light bar is provided by the assembly of the rotator with a base member useful for mounting one or more rotators and other light producing array units. The light bar base member has longitudinal grooves and the mounting enables the rotator to be attached wherever desired along the grooves. The grooves are blind grooves. The rotator has its own base with a plurality of holes in which are provided resilient shock absorbing grommets with holes therethrough. The assembly of the rotator to the light bar base member is via self-threading screws which have heads, parts of which may be washers, which enlarge the diameter of the heads. The screws are of such length that when they engage and are stopped by the bottom of the grooves, the head compresses the grommet sufficiently to provide a resilient shock absorbing connection.

Abstract: A sub-assembly for a light-projecting module has an array of LEDs mounted on a circuit board potted in a tray at the bottom thereof by a solidified body of potting material. The body of potting material and the tray are heat-conductive and serve to dissipate heat generated by the LEDs. A light-emitting module includes the sub-assembly and a reflector. The reflector has a base which is assembled in heat-conductive relationship with the tray, so as to facilitate dissipation of heat generated by the LEDs. The reflector is a parabolic reflector which collects light from the LEDs and projects the light as a beam. The reflector contains an optical element for concentrating or diffusing the light projected from the module. The module may be assembled in a housing having an opening through which the light projects so as to provide a light bar suitable for mounting on the dash or windshield of a vehicle.