Abstract: An effluent precipitation and neutralization chamber for mixing and neutralizing spent photographic developer and fixer. A baffle and long folded ribbons inside the chamber promote mixing of the developer and fixer. A source of iron ions such as fine steel wool is immersed in the fluids. Ion exchange between the steel wool and the photographic fixer recovers silver from the fixer. The desilvered fluid is diluted with wash water before it is discharged from the chamber.

Abstract: A current mode zero-voltage, parallel resonant switching power supply. The disclosed power supply includes a resonant tank comprising an inductorcapacitor pair, and having a variable output level. A solid-state switch controls the energy input to the tank. A comparator compares the voltage or other signal level from the switch to a threshold level so that the switch is closed when the voltage across it equals the threshold, and opened when the current through it corresponds to the threshold level. In one embodiment the threshold is produced by an error amplifier sensing the power supply output voltage, based on the difference between the output level and a reference level. A startup circuit is provided for energizing the tank when the power supply is initially powered, or under a load dump condition.

Abstract: An electrical connector assembly is formed of opposed hermaphroditically mating connectors, having two or more pairs of alternating male and female contact members. Each female contact member is carried by and disposed at the outer end of a linear elongated insulating member projecting from the end of the plug. The insulating members in cross-section are each in the configuration of a sector of a circle having a truncated central edge. The male contact members are disposed between the elongated insulating members. The elongated insulating members are so configured that when two of the connectors are mated together the elongated members will form a cylindrical shape. The connectors will mate together only in one orientation due to the fact that at least one of the elongated insulating members forms an arcuate part of the circumference of a circle that has a different length than at least one of the other elongated members.

Abstract: Paper management apparatus including a work bar mounted to an upright panel. The work bar has a front wall that defines a half moon shaped groove. A mounting clip has a band with a convex surface that nests within the work bar half moon groove. The mounting clip further has a hem that extends out of the work bar half moon groove. The mounting clip hem is inserted into the hem of one of a number of interchangeable paper holding accessories such as slanted storage trays, binder bins, and stackable letter trays. The letter trays and binder bins are made of side walls that assemble to respective opposed ends of trays. The letter trays have respective upper edges that define tabs with a predetermined contour and respective lower edges that define hooks with the predetermined contour. The trays are stacked by sliding the tabs of the first letter tray into the hooks of the second letter tray. The slanted storage tray has a back and a bottom formed with V-shaped pockets. A divider is removably engaged in each pocket.

Abstract: A control circuit for continually testing a photoelectric detector. The detector includes a light source, and a photoelectric receiver having a predetermined drop-out time, attached to a movable storage carriage, spaced apart and substantially sightaligned. The carriage has a reversible electric motor which is controlled by the control circuit, including at least two relays, the contacts of which are connected in series so that the contacts of both must be closed in order for the motor to be energized. The relay drop-out time is substantially longer than the receiver drop-out time. In the circuit, an inverter is connected between the second coil and the light source. This inverter inverts signals received from the second coil and passes them to the light source so that receipt of a signal at the receiver causes the light source to turn off, in turn causing a loss of signal at the receiver, resulting in the light source turning on.

Abstract: A powered striker assembly for collecting loose material on the ground has a shaft mounted for rotation about a horizontal axis at a predetermined distance above the ground. The shaft carries an array of striker members. The striker members preferably comprise elastic nonrigid bodies. In the absence of shaft rotation, the elastic nonrigid bodies of the striker members are normally flexed out of a perpendicular relationship with the ground. In response to centrifugal force generated by rotation of the shaft, the flexed striker bodies mutually assume a perpendicular relationship with the ground for contacting and thrusting loose material. In one arrangement, the striker bodies are bent upon themselves in a U-shape and inserted through holes in the shaft, where they remain without use of external fasteners or the like.

Abstract: A unitary helical coil spring assembly is inserted in a tubular body to form a neon tube support. The assembly is molded of plastic using a mold comprised of two planar blocks in each of which there are a series of axially spaced apart recesses configured to form half convolutions of a spring and there are projections having rounded ends projecting from between half convolution recesses on each mold block which interdigitate and project into the half convolution recesses in the opposite mold block when the planar surfaces are interfaced so the rounded ends cooperate to form a circular inside diameter of the spring when plastic is injected in the recesses.