Abstract: The conversion is effected by adding equal and opposite reference voltages to the analog signal to provide two first output voltage levels. The voltage difference between these levels is converted into a first given number of pulses. The polarity of the analog signal is then reversed during the second half of the cycle so as to be subtracted from the reference voltages for providing two second output voltage levels. The voltage difference between these levels is converted into a second given number of pulses. A function of the first and second number of pulses provides a numerical count directly proportional to the analog signal with all zero drift eliminated. A second conversion can be made to provide a digital read-out which is free from both zero drift and span drift.

Abstract: Load cells for weighing scales are provided with integrally formed flexures for preventing extraneous moments from affecting strain gauges secured to the load cells. The load cell itself includes in its simplest form a rectangular shaped body having cut-outs defining load carrying upper and lower arms and a vertical leg. Recessed areas are provided on opposite sides of the rectangular body between the upper and lower cut-outs to define a shear web to which strain gauges are attached. Flexure webs formed between the cut-outs in combination with further flexure webs formed at one of the ends of the load cell body effect the desired isolation.

Abstract: A captive film loop apparatus moves film through a film gate in a manner to increase the dwell time of each film frame in the gate over that normally available with presently known captive film loop apparatus. Film loops on either side of the gate are held captive by first and second rollers which are moved in unison along a given path for a first given period during which the first roller takes up all film fed to it and the second roller releases all film taken from it. The rollers are then moved in unison along a return path to their original positions during a second given period substantially less than the first given period. Film in the film gate is stationary during the first given period and moved through the gate from one frame to the next within the second given period. The construction is such as to provide for a very smooth acceleration and deceleration of the film so that rapid projection of large film formats is possible without damaging the film perforations.

Abstract: The apparatus is for pre-cooling produce immediately after harvesting of the same and towards this end, constitutes a portable elongated enclosure normally positioned at the field site of harvesting. A detachable dolly supports the enclosure so that it can be moved to various different field sites as required. The enclosure itself supports pallets having containers arranged in two longitudinal rows to define a passage therebetween. An air handling housing in turn incorporates an exhaust fan, cooling coils and appropriate ducting so that refrigerated air is circulated over the tops and sides of the rows of the containers and drawn into the central passageway by the exhaust fan to then again pass into the air handling housing. In other words, a forced air circulation is used to remove the field heat from the containers.

Abstract: The clipper is driven by a flexible shaft from a stationary motor supported by a stand clamped to an edge of a grooming table. Because the motor is not incorporated in the clipper casing as characterizes prior art clippers, the casing is lighter, operates at a cooler temperature and can be made more powerful by utilizing a motor of higher rated horsepower and rpm than the smaller type motors incorporated in a clipper casing.

Abstract: The device includes a base plate, a longitudinally slidable key vise carriage on the base plate, and an overhead support for a manually operable key file. The various components cooperate in such a manner as to permit adjustments in the successive spacing between cuts, angles of the cuts relative to the longitudinal axis of the key as viewed in plan, depth of the cuts and slope of the floor of the cuts, the latter adjustment being effected by securing the key in the key vise in various rotative positions.

Abstract: The shoe sole can either be external or constitute an inner sole to be received within the shoe. It includes a supporting pad having a plurality of circular recesses formed in its underside. A like plurality of identical individual enclosures of resilient material cover the recesses. Each enclosure comprises a series of annular walls successively axially spaced from the recess associated with the enclosure and having successively decreasing diameters, the walls being in partially nested relationship and connected together by a thinner portion of material. The arrangement is such that the enclosure or air chamber will collapse in a telescoping manner wholly within the recess of the pad when walking pressure is applied to the enclosure. Air can escape from each of the enclosures through specially designed openings. The repetitive compression and expansion of the enclosures with each step results in a shock absorbing and cushioning action by the sole.

Abstract: The film gate and registration system is used for motion picture film that is intermittently transported through a gate from one frame to the next. The arrangement is applicable to both motion picture cameras and projectors. A gate is provided with an aperture having solid marginal edge areas. Spaced pressure pads are arranged to be moved into and out of engagement with a film passing through the film gate. The pads press against the marginal edges of the film when the frame is in its dwell period in the gate either for exposure or projection. When the film is to be transported to the next frame, the pressure pads are withdrawn from the marginal edges and the film is lifted away from the aperture plane. In the preferred embodiment, registration indexing pins closely cooperate with the pressure pads in a special fashion to provide unusually precise positioning of each successive film frame at the end of the transport time.

Abstract: The wheel truck for a skateboard or a rollerskate includes a roller coaxially mounted between the left and right skate wheels. This roller is of a lesser radius than the radius of the skate wheels so that it will normally be clear of objects when the wheels are rolling on a flat terrain. However, the roller will engage objects such as a curb edge extending upwardly between the wheels a distance greater that the difference between the radii of the roller and wheels and roll over such objects to thereby minimize loss of momentum of a skater.

Abstract: The free-wheeling latch disengages the wheels of power type wheelchairs from the motors to permit easy manual use of the wheelchair. The latch itself is in the form of a manually movable pin projecting into a bore in the side of the hub. When the pin is moved inwardly, it engages a flange structure secured to the wheel axle and thereby locks the wheel to the axle for operation by the wheelchair motor. When the pin is manually retracted, the wheel and hub are free to rotate independently of the drive system to the axle.