Abstract: The described air compressor has an annular piston received within a cylinder for reciprocal movement to drive pressurized air on both piston strokes to an outlet which is arranged in line with the air inlet and driving power source. A shuttle valve alternately opens and closes ports at opposite ends of the pump cylinder to accomplish valving for the pressurized air. Rotative drive applied to an axially located rotor within the compressor housing via a planetary gear assembly alternately drives the rotor in opposite directions. A gear on the rotor is drivingly related to gears located on two threaded shafts which pass through threaded openings in the piston. Accordingly, rotation of the rotor drives the annular piston from one extremity to another in the pump cylinder.

Abstract: Method and apparatus for magnetographic testing of magnetizable test pieces including pressing a magnetic storage tape upon the test piece, magnetizing the test piece thereof while the tape is being pressed against the test piece surface, removing the tape and scanning the tape by means of a probe which responds to magnetic forces to detect any stored defect stray fluxes.

Abstract: Voltage signals induced in a magnetic probe by stray flux at the location of a defect in a test piece are monitored determining the maximum signal magnitude and maximum signal rise. A quotient of the maximum rise and magnitude is formed and compared with a predetermined threshold value. The sample rate of rise and magnitude is functionally related to the scanning speed thereby providing accuracy independent of the scanning speed.

Abstract: A suspension having each rear axle interconnected with a trunnion journaled in a crossbeam so that each wheel is rotatable about a horizontal axis extending at right angles to the wheel axle. A control link connects the trunnions such that rotation of one effects a corresponding rotation of the other and in the same direction. A double acting spring acts on the link resisting longitudinal movement of the link in either direction. The spring action is of predetermined character for providing the optimal relationship with respect to a self-centering force, camber rate and bump camber resistance.

Abstract: An annular piston is received within a suitably dimensioned cylinder and reciprocally driven to pump fluid on both piston strokes to a fluid carrying line with which the pump is arranged in an in-line relationship. A centrally located shuttle-valve alternately opens and closes ports at opposite ends of the pump cylinder to accomplish the required in-line valving for the pump.

Abstract: The present invention relates generally to an improved fluid compressor and, more particularly, to such a compressor driven by a hydraulic motor, the working liquid of which serves as a coolant for the compressed fluid.

Abstract: A drive control apparatus interconnects with a venetian blind slat ladder assembly for positioning the blind slats at any desired angular relationship and includes a detent that is moved during slat positioning and when a limit stop is reached exerts a back pressure onto the drive apparatus. When the back pressure exceeds a predetermined amount, this causes the drive shaft to overcome a retarding leaf spring pressure and thereby slip rather than drive the slat ladders.

Abstract: A method for testing a metallic workpiece by eddy currents induced by a test coil in the workpiece, in which a measured variable that is a function of the test coil impedance serves as a measure for workpiece physical properties. The circuit includes an oscillator with an amplifier and two resonant circuits adjusted to neighboring frequencies f.sub.1, f.sub.2, the test coil impedance is at least part of the inductive component of one or both resonant circuits and a variable component influences the resonant frequency of one of the resonant circuits.

Abstract: A magnetic field differential probe has field sensors located at spaced intervals along a tensilely stressed diamagnetic wire free of mechanical support between the sensors.

Abstract: The valve passes incoming pressurized fluid through a pair of orifices arranged in opposite side walls of a hollow tubular plug to form two fluid jets which impinge upon one another in the plug interior prior to exiting. The orifices are elongated and selectively covered by an adjustable sleeve which is positioned by manipulation of a valve stem extending outwardly of the valve housing. Further pairs of orifices are angularly arranged with respect to the first pair and the sleeve includes parts which cover the other orifices when a first pair are operative. The valve stem is selectively rotatable to position the sleeve to expose another pair of orifices to the pressurized fluid.

Abstract: The described sport goggles have frames which fit closely about the temples and across the nose, and include enlarged viewing openings with relatively narrow members extending from the top and lower parts of the frame inwardly toward each other in the frame viewing openings. These frame members prevent a ball, racquet, hand or other items from contacting the eye or immediately adjacent parts of the head and face. In a further version where the game ball is relatively small, that part of the frame defining the viewing openings immediately adjacent the nose extends horizontally into the viewing opening, which further restricts the area of the viewing opening and yet does not interfere with the visibility of the player during participation in the sport. An adjustable nose-piece permits precise fitting of the goggles to the wearer's face.

Abstract: A magneto-inductive materials tester has probes which, when brought into contact with the material, produce an electrical signal corresponding to properties of the material desired to be tested. Apparatus for evaluating this test signal has at least one device for producing a compensation voltage to eliminate residual or drift error voltages that may be superimposed on the test signal. The compensating device includes a counting pulse generator, at least one pulse counter connected to the generator at least temporarily, and a digital/analog converter connected to the pulse counter output to provide the desired compensation voltage.

Abstract: In an aircraft autopilot there is provided a first circuit selectively actuatable to connect the glide slope adapter to electrical power during the existence of a glide deflection signal, the glide slope adapter being disconnected from electric power when either (a) the altitude hold is inoperative, or (b) the altitude hold is operative and at least one of the following exists: the radio switch LOC NORM is off, or glide slope coupling has been achieved; a second circuit for maintaining the autopilot under control of a preset heading on the pictorial navigation indicator when the radio coupler is preset for radio navigation control including a third circuit for placing the automatic pilot under control of the radio coupler and interrupting heading control by the pictorial navigation indicator upon actual intercept of the omni occurring; and a selectively actuatable fourth circuit for disconnecting the console pitch signal from the amplifier and interconnecting a pitch signal of predetermined fixed magnitude to

Abstract: The described tube testing apparatus indicates whether a defect is either external or internal, enabling a quantitative classification of defects and an analog representation on location of the defect in the tube wall. The ratio of the signal levels of a defect is taken as a threshold in two different circuit channels. For tubes of a given wall thickness, the ratio of the defect signal levels resulting in the two channels is a fixed number which is a function of the location of a defect in the tube wall causing a defect signal. Uninfluenced test signal voltages from the first channel are available for further evaluation and are applied to voltage discriminators having various threshold voltages.