Whelen Engineering Compnay, Inc.

Whelen Technologies, Inc.

Minnesota Mining and Manufacturing Company

James L Stopa

Todd J Smith

Jon H Lyons

Harold W Lyons

David J Sousa

Paul C Welling

Kevin Michael Smith

Earl B Hoekman

Thomas M Fredericks

Stephen C Bibbiani

H Wayne Lyons

An LED illumination module including an LED lamp with a plurality of light emitting dies on a substrate in combination with an optic having a single focus. The light emitting dies include a single center light emitting die centered on an optical axis and peripheral dies arranged around the center die. The illumination module includes a beam forming optic having a single focus arranged over the LED lamp with the focus on the optical axis of the center die. Light emitted from the center die is substantially collimated by the optic in a focused 'spot' emission pattern. Light emitted from the peripheral dies results in a more dispersed or divergent 'flood' emission pattern. The center die and peripheral dies are independently controlled and the power delivered to the dies can be varied independently to generate different light emission patterns using the same optic.

LED illumination module with fixed optic and variable emission pattern

The disclosed power supply is compatible with two voltage ranges, the midpoint or mean of the higher voltage range being approximately double the midpoint or mean of the lower voltage range. Two equivalent loads and two current sources are re-configured using a relay in response to a detected input voltage exceeding a pre-determined threshold voltage. The disclosed circuit re-configures the load being driven to match the input voltage, rather than re-configuring the voltage to match the load.

Dual range power supply

The disclosed pan-tilt spotlight is a sealed, remote controlled unit which allows continuous 360&#xb0; rotation (pan) of visible or infrared (IR) light sources as well as vertical (tilt) aiming of the light sources 65&#xb0; above horizontal and 25&#xb0; below horizontal. The light sources are solid state (LEDs) which are energy efficient and extremely durable in the field, requiring little maintenance. Light shields are employed to control stray light, thereby enhancing the stealth of the spotlight in covert operations. The rotating parts of the spotlight are supported at several locations spaced from the axis of rotation in a manner that re-directs forces that would otherwise be carried by the shaft. Temperature sensitive current regulators and robust thermal design protect the LEDs from heat damage. Sophisticated motor control allows fast and precise positioning of the light beam and worm final drive gears keep the light beam in position.

Pan-tilt spotlight

Several driver circuits for energizing series arrays of LEDs are disclosed. The LED driver circuits incorporate programmable microcontrollers and switching regulators in circuits that permit precise control of current applied to the series array of LEDs. One driver circuit senses the condition of a SYNC line such that the light emission pattern of multiple LED light sources, each with a driver circuit connected to the SYNC line may be coordinated without need for a central controller. Another driver circuit applies an overdrive current to the LEDs for a first pre-determined time period, then ramps down the applied current to a sustainable level. A four channel driver circuit provides each channel with electronic switches arranged to simultaneously turn on and electrically connect a constant current source to an LED array, resulting in abrupt turn on and turn off of the LEDs.

LED driver circuits

The duration of variations in the potential applied to a single electrical contact, when compared to a reference potential, are measured and employed to command either incrementing or decrementing of an address. The addresses are associated with a table of instructions and an addressed instruction, when read, will produce a discrete warning signal. A desired one of several light flash or audible patterns may be selected by step-wise scrolling through the table in response to manually varying the contact potential.

Pattern selection method and apparatus

Reflector for light assembly

An light source utilizes a parabolic reflector to collimate light emitted from at greater than a predetermined angle relative to the optical axis of an LED arranged at the focus of the reflector. An optional collimating lens is arranged to collimate light emitted at less than the predetermined angle. Both variations provide light in the form of a substantially collimated beam. The parabolic reflector is preferably extended along its focal point to form a linear parabolic section having a linear focal axis. A linear array of LEDs is arranged such that the linear focal axis passes through the area of light emission of each LED. The linear parabolic section may be provided with parabolic dish ends. Alternatively, the ends of the parabolic section may be left open for increased wide angle visibility.

LED light assembly

A power supply for use with an associated light bar assembly suitable for use at a warning light on an emergency vehicle that includes a generally planar printed circuit board having at least one discrete component mounted thereon. A power supply housing surrounds the printed circuit board and includes a generally planar heat sink plate. The heat sink plate is disposed in generally parallel relationship to the printed circuit board and is disposed in thermal conduction relationship with respect to a discrete component. A fastener extends through the discrete component to urge the printed circuit board and the generally planar member together. The discrete component may be a MOSFET.

Encapsulated power supply

A warning light has multiple juxtapositioned arrays of light emitting diodes, each of the arrays defining a plane oriented transversely to the parallel axes of the lenses of the diodes comprising the array. The arrays are supported so that the planes defined thereby angularly intersect. The radiation pattern of the light is controlled by selection of the diodes comprising each array and adjustment of the angles of intersection of the array defined planes.

Multi-array LED warning lights

A high intensity light source employs a plurality of light emitting diodes associated with a unitary reflector subassembly. The reflector subassembly defines an array of frustoconical reflectors arranged in rows and columns with the adjacent reflectors of each row being connected by a diverging slot with reflective wall surfaces. The light emitting diodes are mounted on a printed circuit board which forms a component of heat sink subassembly.

High flux led assembly

A multi-flash strobe light pattern is superimposed on each individual light pulse produced by an incandescent lamp to provide a warning signal of enhanced visibility in a particulate laden ambient environment. The first pulse of each multi-flash strobe pattern is delayed for a time period, subsequent to energization of the incandescent lamp, which is equal to at least 80% of the time required for the incandescent lamp to achieve its maximum light output intensity.

Composite warning light with emission pattern matching

A modular-type lightbar assembly has an elongated base having a bottom panel and a pair of oblique integrally extending front and rear sides. Lens elements are mounted to the base and a cover by lock and groove-type connections. Warning beacon units are mounted to platforms supported on base. The beacon units rotate for sequentially directing light through the front and rear lens elements. The beacon units have an efficient integral base which mounts the rotating beacon and a brush assembly for the motor. An electronic controller is employed to apply a pulse width modulated current to the beacon motor so that a fast and slow motor speed may be selected.

Rotatable warning light assembly

Information as to a direction(s) to be followed to avoid a hazard is unambiguously transmitted by energizing lamps of an array in accordance with stored data whereby unique sequential flash patterns are generated. A selectable pattern includes a long initial flash followed by a plurality of relatively short flashes which progress in stepwise fashion in the direction of desired observer motion, the pattern ending with a terminal lamp of the array being flashed repetitively. The pattern is then caused to repeat after an off time which is of long duration relative to at least the short flashes of the pattern.

Growing community of inventors

Old Saybrook, CT, United States of America

James L Stopa