Abstract: A servo-motor assembly for a machine slide having a rack and pinion drive that includes a servo-motor support with a pinion carrying output shaft all totally supported by and cantilevered on a pair of normally flat parallel springs that bias the motor support and pinion toward the rack to eliminate backlash.

Abstract: An optical pattern tracing system of the type having a tracing head with a scanner that projects a photocell onto a pattern-line with an improved manual resolver for providing control signals to drive the tracing head in an approach direction toward the pattern-line. The manual resolver is a capacitive resolver constructed of foil elements and an angularly adjustable coupling disc mounted directly on a printed circuit board that also carries much of the other control circuitry for the tracing system.

Abstract: An optical pattern tracing system of the type having a tracing head with a scanner that projects a photocell onto a pattern in a closed path and provides two signals for each complete path across a line with an approach control for driving the tracing head toward the pattern-line that permits the operator to preselect either clockwise or counterclockwise tracing. The tracing head approach control includes circuitry that selectively blocks the first or the second pulse from the photocell and then terminates the blocking function shortly after the line is reached. An improved line detector is also disclosed that detects the true center of the line to be traced, and a dual pulse detector is also provided that assures that the scanner is fully locked onto the line prior to switching from manual to automatic control.

Abstract: A platform type weighing scale comprising a differential capacitor transducer having one double-segment movable plate attached to an elongated weighing beam and two double-segment fixed plates attached to a U-shaped channel. The weighing beam is housed within the cavity defined by the channel. The ends of both the weighing beam and the channel are fixed to tape-pulley supported structures to produce turning moments which move the center of the weighing beam in a vertical plane substantially more than the channel is moved in the same plane. This difference in the relative position of the weighing beam and channel translates into a weight responsive change in the relative position of the fixed and movable capacitor plates to produce a weight readout.

Abstract: An optical scanner for a pattern tracing system for scanning an irregular two-dimensional pattern using an optical beam deflection principle. A scanning head is non-rotatably mounted above the pattern on a frame moveable in two coordinate directions. The scanning head reflects an image onto the pattern by a pivotally mounted mirror in the scanning head and is deflected at high frequency in two normally orthogonal planes by the interaction of a pair of perpendicularly related electromagnets with a permanent magnet. The geometric axis of the mirror nutates around a scan axis to provide a generally circular scan image on the pattern. The axis about which the mirror nutates, referred to as the scan axis, is shiftable from a fixed reference axis to achieve offsets for the scan image to provide both forward offset and "kerf" offset perpendicular to the forward offset. A control circuit derives out of phase alternating signals for the two scanner coils to cause this nutational motion of the mirror.

Abstract: A circuit for safely admitting fuel to a burner, igniting the fuel, detecting the presence of flame at the burner, and preventing the escape of unburned fuel from the burner if ignition is not accomplished or the flame is interrupted. An initiation circuit operates a control signal generator during a time delay period and a valve operating circuit opens a fuel valve to admit fuel to a burner. An igniter circuit is operated in response to energization of the valve operating circuit to produce sparks for ignition of the fuel. A flame detector circuit powered by the valve operating circuit detects the presence of flame and, in response, the operation of the control signal generator is maintained and the operation of the ignition circuit is interrupted. The operation is fail-safe, the detection of flame is reliable despite power supply variations, and no power supply transformer or valve operating relay is required.

Abstract: A weighing scale having a differential capacitor transducer for generating an electrical signal proportional to the movement of a variable capacitor plate. The differential capacitor has a pair of fixed capacitor plates disposed in a parallel, spaced relationship with respect to one another with the variable capacitor plate being symmetrically disposed between the fixed plates. Each of the fixed plates is formed with double segments. Each segment of a plate is electrically isolated from the other segment of that plate and opposite adjacent segments of both plates are electrically connected to one another. A square-wave input voltage is applied between both sets of commonly connected segments. A square-wave output voltage is developed at the variable capacitor plate whose phase and amplitude varies in response to the weight of an object being weighed.

Abstract: A platform weighing scale having a transducer with a movable element to translate weight responsive platform motion into a weight responsive electrical signal and in which the platform is movably supported relative a scale base by one or more pulley and tape motion linkages which also actuate the transducer element.

Abstract: A digital clock having backlash-free gearing between a step motor and digit wheels that indicate time. The gearing includes an input pinion connected to the step motor, intermediate gearing driven by the pinion and an output ring gear driven by the intermediate gearing and connected to drive a seconds digit wheel of the clock mechanism. A pivotal bracket rotatably carries the intermediate gearing and is biased in one direction by a spring so that the intermediate gearing is urged into backlash-free engagement with both the input pinion and the output ring gear. The bracket tilts as well as pivots to permit the intermediate gearing to properly mesh with both the input pinion and the output ring gear.

Abstract: A particulate products of combustion detector having a light emitting diode and a photovoltaic solar cell coupled one to the other to serve as a particulate or smoke sensor. A free-running multivibrator periodically pulses the light emitting diode to corresponding pulses of light emission having a first pulse-repetition frequency of about 80 Hz. and a duty cycle of about five percent. The output of the solar cell is connected to the input of a ringing amplifier to generate at the amplifier output a ringing pulse sequence having the same pulse-repetition frequency as that of the light element emissions in response to the detection of the particulate products of combustion. The ringing amplifier has a passband of about 500 Hz. centered about a frequency of about 1000 Hz. A detector is connected to the output of the ringing amplifier to generate a peak voltage responsive and proportional to the greatest voltage amplitude of each ringing pulse, namely, that of the first half-cycle of each ringing pulse.

Abstract: A contour tracing apparatus in which the coordinate drive motors are cantilever supported on simple plates and needle thrust bearings to permit the motor pinions to be spring biased into engagement with the respective racks for moving the scanning head and associated tool. Kerf offset is provided by rotation of the scanning head optical assembly about a pivot member, which can be translated along a zero kerf adjustment line to provide forward offset. The pivot member is also eccentrically rotatable in response to rotation of the optical assembly about another axis to properly align the photocells of the optical assembly with a zero kerf mark. The optical assembly includes a plurality of lamps spaced about the photocells and one integral lens structure having annular prism surfaces encircling a convex lens surface to direct light from the lamps to the contour and from the contour to the cells.

Abstract: A warning system for detecting a burned out or defective bulb for a motor vehicle is disclosed. A transmitting circuit is connected to detect current flow through the bulb to be monitored. Failure of the bulb to draw current causes the transmitting circuit to produce a series of small voltage pulses on the battery line. These pulses are detected by a receiving circuit which causes an outage indicator light to be illuminated.

Abstract: A spray dispenser for dispensing liquid in spray form, having a housing, a rotatable spraying disk mounted to the housing, a liquid feeder for supplying liquid from a receptacle to the underside of the disk, and a fixed member spaced below the underside of the disk. The fixed member cooperates with the disk to define a metering opening which regulates the volume of liquid fed to the disk and which can be set in a zero position. A fixed threaded collar is in threaded engagement with a control cap having a tapered inner flange.

Abstract: A simplified gear drive mechanism for an indicating device such as a clock. The output shaft of the indicator's drive motor carries an eccentric which orbits a multiple gear tooth orbiting gear. One gear on the orbiting gear engages a stationary ring gear having a different number of teeth while another gear on the orbiting gear engages an output ring gear having a different number of teeth. This output ring gear may, for example, be employed to drive the minute hand of a clock. To provide multiple indicators such as required in a clock, a second orbital gear train is provided having an eccentric on the output gear of the first gear train for the purpose of orbiting an orbiting gear in the second gear train. An output ring gear in the second orbiting gear train is employed to drive the hour hand of the clock. In another embodiment of the present invention, a similar orbiting gearing arrangement is employed for driving a digital indicator, such as a digital clock.

Abstract: A warning system for detecting a burned out or defective bulb for a motor vehicle is disclosed. A transmitting circuit is connected to detect current flow through the bulb to be monitored. Failure of the bulb to draw current causes the transmitting circuit to produce a series of small voltage pulses on the battery line. These pulses are detected by a receiving circuit which causes an outage indicator light to be illuminated.