Abstract: A vaulting board is fastened at one end to a frame and slopes up under the action of two spaced apart, concave upwards, leaf springs carrying rollers on each end which contact the under side of the board. The spring centers are clamped in assemblies carrying transverse shafts at the bottom and the curved ends of J-bolts fit around the shafts and are connected to the frame, so that the springs pivot about the shafts axes under vaulting impact to equalize the stresses impressed in the board by the spring ends.

Abstract: A radar loaded, hollow yacht mast is disclosed which is pivoted at the bottom to the deck by a tri-sectioned elastomeric torsion spring hinge assembly in which the torsion is produced by relative rotation between the inner section and the two outer sections. The torsional resistance of the hinge assembly prevents the mast from falling when the bolts and stays are removed and the restoring force in the spring elastomer when the mast is pivoted flat to the deck assists in raising the mast back into its upright position. A hollow, flanged mounting connecting the hollow mast to the movable section of the hinge assembly prevents sea water from entering the hollows. Provisions are provided for pre-loading the hinge spring with a torsional stress in either direction when the hinge is closed.

Abstract: This invention relates to automatic gain control (agc) circuitry and more particularly to circuitry for supplying respective automatic gain control signals to an amplifier that repeatedly receives a given sequence of signals. Each one of the signals in each sequence is sampled and compared with a reference voltage in a respective feedback loop. The respective agc loops are coupled to the amplifier in a predetermined sequence to control the gain of the amplifier in a desired manner. The steps in this predetermined sequence are initiated by an external trigger and by the receipt of the signals to be controlled.

Abstract: A throat plate of a sewing machine with a feed plate is provided with disc type bearings retained in fixed position adjacent to the needle hole of the throat plate to support and provide low friction surfaces in contact with the feed plate.

Abstract: The battery assembly is housed in the casing of the flashlight so as to be axially slidable therein, whereby the displacement of said assembly in one direction closes the electrical circuit comprising the bulb, and the displacement in the opposite direction opens said circuit. A pushbutton radially extends from the flashlight casing. The said pushbutton is provided with a cam-shaped portion cooperating with an axially slidable cam follower to transmit the axial displacement to the battery assembly.

Abstract: A well instrument is isolated from the high temperatures of a surrounding earth formation by enclosing the instrument within a heat insulative jacket structure, preferably a dewar having spaced walls with a vacuum therebetween, with a heat sink contained in the jacket above the instrument assembly, and with a heat pipe extending upwardly from the instrument assembly to the heat sink and containing a fluid which by evaporation at a lower point and condensation at a higher point will conduct heat upwardly from the instrument assembly to the heat sink but not downwardly therebetween. The heat pipe preferably projects upwardly beyond a top portion of the insulating jacket to the location of a convector element which is exposed to the temperature of fluid or air at the outside of the insulating jacket to transmit heat from within the jacket to its exterior but not in a reverse direction.

Abstract: Method and apparatus for nondestructively testing each incremental area of a ferromagnetic sample by first passing a steady magnetic flux field through an area in a first direction and producing an inspection signal in response thereto, and then passing a steady magnetic flux field through the same area in an orthogonal direction and producing a second inspection signal in response thereto. The magnitudes of the two inspection signals corresponding to a given incremental area are added to produce a composite signal whose magnitude is the sum of the two signals. The composite signal associated with a given incremental region is displayed on a visual presentation means at a location corresponding to the location of the incremental region on the ferromagnetic sample and with an indicia, such as color, that is a function of the magnitude of the respective composite signal.

Abstract: The free corner of a sail is secured to a boom containing mechanisms which transform the lateral forces acting on the boom into axial pulling forces on the sail end, thus maintaining the sail constantly in stretched condition, regardless of the elastic deformation undergone by the boom.

Abstract: An electromagnetic contactor having a box shaped frame DC solenoid, a plunger with one end attached to a stamped metal bracket which, in turn, is attached to a pusher assembly. The pusher assembly includes the movable contacts. As the solenoid plunger is extended and retracted, the contacts associated with the assembly will engage and disengage in response thereto. The solenoid is mounted in a base and is biased up against the carrier by a curved spring washer. The coil terminals are part of the solenoid and are trapped or contained between guide walls of the base to provide strain relief. The coil terminals are not rigidly attached to the base so as to allow the solenoid to float and to prevent fatigue of the terminals.

Abstract: An overhead dispenser having vertically telescopic movable shelf units.