A system for controlling the position of a four-position rotary valve from a remote location, for example, in an airplane. A manually operable, single-pole, multi-throw switch supplies a voltage to a selected one of a plurality of normally closed limit switches via a selected one of a corresponding plurality of contacts of the manually operable switch with which the pole thereof is engageable. A motor then drives a cam and the valve until the cam opens the said one limit switch. The valve is the...

A fluid system for controlling the position of an output according to the position of an input and comprising a first variable flow control valve including a sensor arranged for sensing the position of the input and operative for generating a first fluid pressure signal dependent on the input position, a second variable flow control valve connected to the first valve and including a sensor arranged for sensing the position of the output and operative to produce a second fluid pressure signal dep...

An encoder for accurately determining the position of one body relative to another consists of an optical mask carried by one body which moves through the focal point of a concave reflector carried by the other body. The reflector produces an image of the mask in the same plane of the mask and the mask and its image together produce positional information which is utilized by a photo-sensitive detector. The optical pattern of the mask is arranged such that the detector receives constant variatio...

A position sensor includes first and second parts rotatable relative to each other. The first part includes first and second half-ring conductors insulated from each other. The conductors define a sliding surface and the ends of the conductors are spaced to define a slot interrupting the sliding surface. The second part includes a spherical ball closely received in a bore normal to said sliding surface. A spring resiliently urges the ball into said slot to make contact between the two conductors...

A manually operable position lock for a hydraulic actuator (10) adding a cylinder (20) and a piston rod (22) with a stop finger (61) for actuating a push rod (60) to close a valve (32) and prevent fluid egress from the cylinder. The lock includes a pivot bracket (110) carried by a push rod, a control lever (111) pivoted to the pivot bracket, a link (114) pivoted to the control lever and slidably receiving the push rod, and a helical spring (120) carried by the push rod and engaging one end of th...

An electrical transducer for indicating the position of an element movable n a predictable path, such as angular rotation, has no electrical parts on the movable element. A magnet mounted to the movable element traces a fixed path which lies adjacent to a stationary tubular enclosure containing liquid suspending a mass of ferromagnetic, electrically conductive material, the magnet drawing the mass of particles along within the tube on movement in its fixed path. Electrodes spaced on opposite sid...

A position sensor comprising a movable member functionally connected with an operative device and moving in response to a positional displacement of the operative device, a displacement-pulse phase conversion unit including a magnetically soft amorphous metal member undergoing stress variations produced by the displacement of the movable member and an electrical coil wound on the magnetically soft amorphous metal member. A pulse voltage is applied to one end of the electrical coil, the other end...

A nuclear reactor system is described in which a position indicator is provided for detecting and indicating the position of a movable element inside a pressure vessel. The movable element may be a valve element or similar device which moves about an axis. Light from a light source is transmitted from a source outside the pressure vessel to a first region inside the pressure vessel in alignment with the axis of the movable element. The light is redirected by a reflector prism to a second region ...

A position indicator for monitoring movement of one part of an assembly relative to another--e.g., for monitoring the relative positions of the movable and fixed jaws of a gyratory crusher. The position indicator has a body which is fixed to a probe suitable support and a variable capacitor which responds to movement of the member to be monitored to adopt a capacitance value which is characteristic of each position of that member relative to the support. The capacitor is connected into an electr...

A sealed position transducer which is self-wiping and which is readily adaptable for providing both linear and nonlinear electrical outputs. The transducer includes a housing, a resistive element received in the housing, and a flexible membrane, having a conductive portion formed thereon facing the resistive element, disposed over the resistive element and attached to the housing to seal the interior of the housing from the environment. An object whose position is to be sensed or measured is mou...