Abstract: An improved jam compensating control valve (45) includes a spool (65) which blocks and unblocks a flow passage through the valve. The spool is slidably disposed within an inner sleeve (60) which, upon jammed interengagement with the spool moves therewith, thereby connecting drain passsages (180, 182, 185, 190 and 195) in the surface of the spool with outlet passages (120 and 125) communicating with an associated actuator (5) for actuator draining in response to such valve jamming.

Abstract: A pressure measuring device is provided with an indicator such as a bourdon tube (10) for indicating the absolute value of the difference in pressure between fluids applied to the indicator through first and second conduits (15) and (20). Valve means (25) including an element (100) actuable in response to the pressure in conduits (15) and (20) consistently applies the higher pressure fluid to that portion of the indicator adapted to receive such higher pressure fluid and the lower pressure fluid to that portion of the indicator adapted to receive the lower pressure fluid. Optical means such as transmitter (115) and receiver (120) are provided for indication of the sign (positive or negative) of the pressure difference.

Abstract: A digital vortex shedding flow measuring transducer (10) includes an optical conductor (20) cantilevered to a conduit (15) accommodating the flow and an optical receiver (35) which intercepts an optical signal from the conductor as the conductor vibrates in response to vortices shed therefrom due to fluid flow thereover.

Abstract: An improved optical transducer includes optical transmitter and receiver heads and an encoder plate movable therebetween on channel-shaped tracks integral in part with an inner housing. The encoder plate, and optical heads are disposed in an optical fluid which minimizes light refraction between those optical components, cushions against shock and vibratory loading, and lubricates the encoder plate tracks. The transducer includes an input shaft connected to the encoder plate by means of a coupling which isolates the encoder plate from misalignments of the input shaft and eliminates free-play in the connection between the encoder plate and input shaft, thereby eliminating backlash in the reciprocation of the encoder plate for improved transducer accuracy.

Abstract: A self-flaring rivet and the method of making the same is disclosed. The end remote from the rivet head carries the swaging mechanism that is pulled outwardly to flare the end, inherently applying a tension force. This swaging mechanism also can be designed to remain in the rivet end or be pulled out completely. In the first instance the working stem of the swaging mechanism is broken off.