Abstract: A solenoid having reduced noise and jarring characteristics which includes a small shock absorbing sphere of rubber or other elastomeric material freely mounted between the solenoid armature and a stationary core piece of the solenoid so as to be engaged and compressed by the armature at the end of its travel.

Abstract: An electronic timing system for controlling a plurality of electrically controlled watering valves comprising a free running multivibrator circuit having a plurality of individually adjustable resistor-capacitor circuits for controlling the frequency. A divide-by-N counter, when filled, controls a stepping counter for successively activating different ones of the valves and, in turn, selects different ones of the resistor-capacitor circuits to control the time each of the valves is activated. Operation of the multivibrator circuit is initiated by a clock operated day-of-the-week counter having pre-settable switch means for enabling or disabling operation of the multivibrator circuit during any selected day. A repeat cycling control device is provided to selectively cause repeated cycling for different numbers of times and a delay device is provided to delay repeat cycling for different time periods.

Abstract: A multiple garment hanging device embodying a vertically supported elongate track member. A plurality of hanger slides, each carrying a garment hanger, are slideably mounted on the track member and limit against each other, the lower most one limiting against a stop on the member. By rocking a hanger slide carrying a selected garment, the slide and garment may be removed from the track member.

Abstract: Guide means for a serially operable wire matrix printer head wherein a guide is provided for linearly and pivotally guiding the printing end of the head adjacent and parallel to the plane of the paper. Independent means are provided to pivotally support the opposite and heavier end of the head and for permitting movement of such end in a direction substantially at right angles to the plane of the paper.

Abstract: A key controlled lock for electrical switches, etc., in which a rotatably supported plastic switch actuator element is provided with a substantially diametrically extending keyway at one end to receive a key. Locking fingers of a plastic yieldable locking device normally engage in opposite side of the keyway. The key, upon insertion in the keyway, cams the fingers outwardly to release the actuator element for rotation by the key.

Abstract: A paper rewind roll drive for printers of the type in which the paper strip is advanced for both line spacing and to bring the last printed line to the viewing station and is thereafter retracted to position the next print line at the printing station, the drive comprising means for enabling the rewind roll to retract incrementally at the start of a print cycle, and a one-way drive effective after the usual paper advance following a printing operation to impel the rewind roll in an advancing movement with sufficient force to cause it to overtravel and thus take up any slack in the strip brought about by the usual line spacing advancement or otherwise.

Abstract: A straight dental handpiece comprising a pair of telescoping housing barrels which can normally swivel relative to each other, one containing a chuck and the other containing a vane type air motor. A change speed transmission is entrained between the motor and the chuck, such transmission being adjustable to change speeds by relative endwise movement of the barrels. Opening and closing of the chuck is accomplished by relative rotation of the barrels while holding down a stop button. A reversing valve, also on the handpiece, is movable into either of two positions relative to one of the barrels to supply air under pressure to either of two passages to drive the motor in one direction or the other.

Abstract: An optical grating having expansion characteristics equivalent to the thermal expansion characteristics of a preselected material is formed by providing a thin grating sheet of a material different from the preselected material, forming spaced slits in the sheet to overly an opening in an underlying plate of such preselected material, thereafter securing the sheet to the plate along narrow zones outside the opening, and finally removing the portions of the sheet lying outside such zones.

Abstract: A push-button combination lock for doors or the like having buttons which must be pushed in a prescribed combination and prescribed number of times to release the lock. The lock may be reset to a new combination by use of the same pushbuttons when operated in accordance with the newly desired combination. No tools or dismantling of the lock is required to change the combination. A bypass feature enables one to bypass the lock from the inside of the door.

Abstract: A diameter sensing, reversible ribbon drive mechanism including disabling cams pivotal about the axes of the ribbon spools for disabling the drive and detent pawls for one spool and enabling similar pawls for the other spool. A first link connecting the drive pawls is oscillated during each printing cycle. A second link connecting the disabling cams carries a coupler which is moved into one coupling relation with the first link by a diameter sensing device which senses a depleted condition of one of the spools to cause the first link to transfer movement to the second link to reverse the conditions of the drive and detent previously enabled pawls.

Abstract: A normally closed wafer thin switch, particularly intended for pilferage type burglar alarms, comprising a flat base plate of insulating material having an opening therein and a pair of leaf spring contacts attached to one peripheral portion of the plate and extending over the opening. Free ends of the contacts normally engage each other to complete a circuit. A raised tab on a first of the contacts overlies an opposite peripheral portion of the plate whereby, when an object is placed on or against the switch, the tab is depressed against the plate, causing opening of the switch.

Abstract: A cyclically operable clutch in which first and second driven gears are provided with interrupted gear tooth sections normally located opposite a motor driven drive gear. The second gear is operably connected to a cyclically operable driven mechanism and the first gear is spring urged to rotate relative to the second gear. A latch normally maintains the first gear out of mesh with the drive gear. Upon release of the latch, the first gear is spring advanced into mesh with the drive gear and a lost motion connection between the driven gears transmits rotation to the second gear to advance the latter into mesh with the drive gear.

Abstract: An internal combustion engine comprising a cylinder head with a rotary intake and exhaust valves mounted on the head, the head being interchangeable with cylinder blocks intended for conventional poppet type valve engines. According to a basic aspect of the invention, primary and secondary combustion chambers are provided which are isolated from each other by the piston when at the top of its stroke, enabling combustion to initially take place in the primary chamber with a reduced amount of fuel. Optionally, means are further provided to vary the intake valve opening in accordance with changes in speed of the engine.

Abstract: A squeeze type printer for papers or stacks of papers having varying thicknesses wherein a printing platen is advanced to impress the paper against type bearing members by a yieldably driven cam element connected in series with a positively driven cam element. The yieldably driven cam element is self-locking and acts to advance the paper or paper stack against the type bearing member. Concurrently, the positively driven cam element acts to further advance the paper to cause the printing impression.

Abstract: A squeeze printer for papers or stacks of papers of varying thicknesses wherein a plurality of printing platens are provided comprising individual flexible wall sections of a paper supporting chute which will accommodate different thicknesses of paper or stacks of paper. An actuator is effective through selectively disabled yieldable interposers to transfer a printing force through the platens to the paper.

Abstract: A water barrier for floor safes comprising a removable lid having an elastomeric sealing O-ring extending around the periphery of a relatively rigid rim thereof to engage the inner surface of the case of a floor safe, the lid having a hollow central knob which facilitates removal of the lid and which extends over the safe door lock. The portion of the lid within the peripheral rim is relatively flexible whereby to flex in response to changes in atmospheric pressure against the lid.

Abstract: A straight dental handpiece comprising a pair of telescoping housing barrels which can swivel relative each other, one containing a chuck and the other containing a vane type air motor. A change speed transmission is entrained between the motor and the chuck, such transmission being adjustable to change speeds by relative endwise movement of the barrels. Opening and closing of the chuck is accomplished by relative rotation thereof a limited amount. A reversing valve, also on the handpiece, is movable into either of two positions to apply air under pressure to either of two passages to drive the motor in one direction or the other.

Abstract: An inexpensive, compact and yet highly accurate instrument for transmitting coded signals representing altitudes at which an aircraft is flying, the instrument comprising an altitude sensing unit and a separate encoding unit operatively connected to the sensing unit with means for finely and precisely adjusting the encoding unit relative to the altitude sensing unit.