Abstract: An electromagnetic actuator is disclosed comprising a core assembly including a plurality of pairs of permanent magnets aligned along a given axis. Each of the pairs of magnets have like magnetic poles facing each other and opposite magnetic poles facing away. The pairs of magnets are spaced apart along the given axis and opposite poles of adjacent pairs face each other. Regions of high density magnetic lines of flux of opposite polarity extend generally transversely of the given axis from adjacent pairs. Included are means for providing a low magnetic reluctance between the spaced apart adjacent pairs. Also included are means for defining a continuous low reluctance path extending alongside the core from the magnetic pole forming one end of the core to the magnetic pole forming the other end thereof and spaced over the regions of high magnetic density so as to define magnetic gaps to the core in the area of the regions.

Abstract: A linear motor which utilizes the magnetic attraction between a washer formed from a ferrous material, e.g., steel, and a magnetic pole of an armature for automatically returning the armature to its original position upon the deenergization of a field coil. The washer is originally located in alignment with and in surrounding relation to one of the effective poles of the armature. The stroke of the armature is limited to a distance which insures that at the end of the stroke the one effective pole will be located closer to the washer than any other effective pole. Upon deenergizing the field coil, the magnet attraction between the one effective pole and the washer will cause the armature to return to its original position.

Abstract: Photographic apparatus for controlling the opening and closing of a photographic shutter. In a preferred embodiment, the apparatus includes a linear motor having a first output for incrementally driving the blades of the shutter from a closed orientation to an open orientation. The linear motor includes a second output which rapidly returns the blades to the closed orientation to terminate the exposure interval. In an alternative embodiment of the invention, the coil of the linear motor is energized in manner so as to create a magnetic field which is in opposition to a magnetic field which exists between two permanent magnets mounted within the linear motor to drive the shutter blades into an open orientation. One of the magnets is fixedly secured in place while the other magnet is the armature of the linear motor and accordingly is connected to the shutter blades.

Abstract: An electromagnetic actuator has a motor that indexes an armature element repeatedly by one step from a rest position, and has an electromagnetic clutch coupled with the armature element to increment an optical element that controls light according to relative position. In adjustable polarizing sunglasses, the actuator incrementally rotates a polarized element in each lens in response to the brightness which a sensor receives through the sunglasses. An electrical control circuit compares, in each operating cycle, the sensor signal with high and low reference values to select the motor drive signal.

Abstract: An intrusion alarm system utilizes an inertially responsive sensor preferably present as a pendulum actuated reed switch. Logic circuits provided within the system provide, an efficient pulsating alarm at dual frequencies optimized for human recognition. In both arrangements, a unique dual delay arrangement is provided, one delay commencing with the arming of the device to permit adequate time for the setting of a sensing switch. A second delay arrangement is provided at the option of the operator for purposes of delaying the activation of the alarm once the sensor switch has been tripped. This feature may be utilized to permit entrance through a door or the like upon which the unit is mounted wherein the device can be deactivated prior to assuming an alarm sounding condition.

Abstract: A photoflash unit for use with a camera having a shutter mechanism, a firing pulse source, and an inhibiting arrangement connected to the shutter mechanism, the inhibiting arrangement including a detecting network for sensing first and second resistance conditions, and, in response to the second resistance condition, for inhibiting operation of the shutter mechanism. The unit comprises a multiple array of photoflash lamps adapted for connection of a given array to the firing pulse source and arranged with each lamp of the array to be fired individually and sequentially thereby, and including a radiant energy responsive switch positioned adjacent the last lamp of the given array so as to initially provide the first resistance condition, and then provide the second resistance condition in response to the firing of the last lamp.

Abstract: An intrusion alarm system of a variety utilizing an inertially responsive sensor preferably present as a pendulum actuated reed switch. Logic circuits provided within the system provide, in one embodiment, an efficient pulsating alarm at dual frequencies optimized for human recognition. In another arrangement, a unique dual delay arrangement is provided, one delay commencing with the arming of the device to permit adequate time for the setting of a sensing switch. A second delay arrangement is provided at the option of the operator for purposes of delaying the activation of the alarm once the sensor switch has been tripped. This feature may be utilized to permit entrance through a door or the like upon which the unit is mounted wherein the device can be deactivated prior to assuming an alarm sounding condition. In each of the circuit embodiments, an arrangement is provided wherein, once tripped, the alarm will continue to sound for designated intervals even though turned "off".

Abstract: Smoke detector apparatus characterized in the utilization of solid state components in conjunction with standard primary batteries as a power source. Operating under photo-optical principles, the apparatus incorporates a solid state detector which, while having a low current drain characteristic, exhibits dark current phenomena. A stabilization network is provided to accommodate for this phenomena which includes an amplifier having a transistor stage and means for clamping that stage in a partially forwardly biased state. Detection of smoke causes the amplifier to generate a signal output as a step function.

Abstract: An intrusion alarm system incorporating an inertially responsive sensor arrangement which, in one embodiment, is provided as a body of mass suspended in pendulum fashion within a compact housing. A permanent bar magnet suspended therewith operates in conjunction with a manetically actuable switch to provide highly responsive and reliable sensing. A logic circuit provides a responsive, efficient pulsating alarm at dual frequencies optimized for human recognition, and a wireless magnetic remote disarm feature is provided.

Abstract: An exposure control system is provided for a photographic apparatus in order to selectively actuate drive means including a tractive electro-magnetic means together with other instrumentality means to perform various functions in a predetermined order in the course of producing a photographic record. The control system includes a galvano-magnetic effect means having a predetermined output signal condition responsive to the magnetic field condition of the tractive electro-magnetic means. The galvano-magnetic effect means includes a Hall effect switching device stationed in proximate relation to the tractive electro-magnetic means.