Abstract: A wire guidance system for a materials handling vehicle, such as a turret stockpicker, detects an alternating signal carried by a buried wire. Two sets of four sensors each are carried at either end of the vehicle. These sensors define regions, and a procedure is provided to determine in which region the wire is located. The distance and angle of the vehicle is determined by reference to the distance measurements of each sensor set, as calculated by a microcomputer. A self testing circuit is provided to insure proper operation of the sensors and associated circuitry.

Abstract: An apparatus for measuring torque characteristics of devices (20, 73) includes a first shaft (19) having torque applied thereto by a first device (20) and a second shaft (41) having torque applied thereto by a second device (73). Sensing elements (31) are provided which detect the forces generated by the torque of the first and second shafts (19, 41) and produce electrical signals proportional to the forces detected. A first coupling device (25) transfers the forces generated by the torque from the first and second shafts (19, 41) to the sensing elements (31). A suspension mechanism (57) permits the second device (73) to move laterally independent in two spatial dimensions with respect to the first device (20) so as to minimize any effects from mechanical misalignment and the structural support frame (10). The apparatus can be adapted to measure frictional characteristics of devices (20, 73) by providing an actuator (93) for applying a torque to a third shaft (92).

Abstract: A laterally movable ultrasound transducer, comprising the sensor of a rail fault detection device, is automatically centered on the rail as the detection device moves along the rail. The sensor includes a pair of ultrasound receiving transducers positioned to either side of a transducer which generates and receives ultrasonic energy. Signals provided by the receiving transducers are compared and any difference therebetween employed to control the lateral position of the sensor with respect to the rail.

Abstract: A large bore, long stroke, low friction, hydraulic actuator having dual hydrostatic bearings permitting elastic deformation of the piston rod while inhibiting metal to metal contact between either the piston head or the deformed piston rod and the walls of the hydraulic cylinder. The actuator employs a safe and highly reliable metering orifice cushion decelerating means. Piston displacement is constantly monitored by a completely internal, magnetostrictive, sonic delay line displacement measuring means.

Abstract: In a hot chamber method of pore-free die casting in which a reactive gas flushes non-reactive gas such as air from a die before a material is cast therein, the material displaces non-reactive gas from the gooseneck and nozzle through which the die is filled before the reactive gas flushes the die. The material then does not push non-reactive gas into the die as it fills the die. Apparatus for practicing the method comprises servo-control means for filling the gooseneck and nozzle with the material before the reactive gas flushes the die to displace non-reactive gas therefrom and then filling the die with the material after the reactive gas has flushed the die.

Abstract: In a hot chamber method of pore-free die casting, a gas which reacts with the cast material flushes air from a passage in a nozzle, sprue bushing, and at least a portion of a gooseneck through which the material fills the die cavity, as well as from the die cavity. The reactive gas replaces the air in the passage so that air is not forced into the die cavity by the material when it fills the die cavity. Air in the die cavity would form pores in the cast material. Hot chamber apparatus for practicing the method has a bore communicating with the passage for flushing the passage with the gas. A valve closes the bore when the material fills the die cavity so that the material only enters the die cavity. A heating element heats the valve to prevent the material from solidifying about the valve and thereby interfering with its operation.