Abstract: In a web handling apparatus for continuously supplying a running web to a web-consuming machine using a main accumulator to provide uninterrupted feed of the web during splicing of the trailing end of an expiring roll to the leading end of a ready roll, an improved ready-roll acceleration technique uses a supplemental accumulator disposed between the ready roll and the splicing head to enable the ready roll to be accelerated prior to completion of the splice. This technique permits the use of a smaller main accumulator and/or increased running speeds. In fact, the total storage capacity of the main and supplemental accumulators can be less than that of the single accumulator of conventional apparatus of this type. Furthermore, the running roll can be slowed without adverse consequence so as to reduce web tension upsets. The invention is also useful in web winder/splicer applications.

Abstract: A pair of disc permanent magnets axially magnetized are fastened together in backing magnetic relationship with adjacent end faces of the same magnetic polarity and fastened to a housing. A ring of magnetic fluid around the inside edges of the permanent magnet discs engage a rotatable shaft and coact with the disc to seal the region between the shaft and housing. A bearing comprises a number of cascaded thin discs surrounding a nonmagnetic shaft. Nonmagnetic discs of thickness less than that of each magnetic disc may separate adjacent magnetic discs. Pole pieces of thickness less than that of each magnetic disc may separate adjacent magnetic discs and terminate in opposed pole faces adjacent the shaft defining a gap therebetween of gap width less than the thickness of each permanent magnet disc.

Abstract: An optical encoder housing is rotatably mounted upon a hub secured to the shaft of a motor typically by a set screw. The hub also carries the encoder disc. A circular leaf spring is fastened by studs to the motor housing and the encoder housing. Alternatively a spring couples the hub to the motor shaft while the encoder housing is secured to the motor housing.

Abstract: A magnetic liquid seal comprises a single axially magnetized permanent magnet in the shape of a flat washer having magnetic liquid captured on the inside or outside diameters, or both. Leakproof sealing is achieved between either the outside diameter and an external housing or between the inner diameter and an external shaft.

Abstract: An electric force motor includes two movable and independently actuatable coils energized by a single magnetic circuit. Air gaps are formed at respective ends of a tubular permanent magnet between a core of magnetically permeable material mounted within the magnet and pole pieces attached to opposite ends of the magnet. Such a configuration thus establishes a serial magnetic circuit connecting the magnet and the core through each of the air gaps. The two coils, each positioned within the respective air gaps, receive independent electrical input signals to develop corresponding output forces. Interactions between each coil that would tend to affect accuracy are minimized by choosing a magnet of high coercivity and by limiting the amount of input current applied to each coil.

Abstract: An automatic air deflation valve is provided for use with a sphygmomanometer type blood pressure measuring instrument. The valve comprises a housing having an air flow channel extending through the longitudinal extent thereof and at least one air deflation port extending outwardly from said channel. The port includes a deformable diaphragm supported only on its outer edges and having a central aperture extending through the thickness thereof. The diaphragm is adapted to deform in accordance with the air pressure applied against it from said channel to automatically adjust the size and shape of said aperture, thus producing a constant air deflation rate therethrough.

Abstract: A liquid filled differential pressure transmitter includes a metallic measurement diaphragm within a pressure chamber and a pair of isolation diaphragms sealing the chamber from the process fluid which serve to transmit the applied pressure signals to the measurement diaphragm. The isolation diaphragms bottom against mating back-up surfaces to limit deflection of the diaphragm during overrange pressure conditions. An electrically conductive liquid fills the chamber so that measurable electrical resistances are established through the liquid between the measurement diaphragm and a pair of electrodes adjacent thereto formed on opposite walls of the chamber. As the measurement diaphragm deflects in response to applied pressure signals, the electrical resistance between the diaphragm and each of the electrodes changes providing an output signal which is a function of the applied differential pressure.

Abstract: An external magnetic field retains a layer of magnetic liquid as a protective covering over an element, such as in slide wire potentiometers and in pressure measuring diaphragms.

Abstract: A method and apparatus for protecting the transducer in a liquid-filled differential pressure transmitter having stroke limited, isolation diaphragms from exposure to overrange pressure are disclosed. Bidirectional overrange pressure protection is provided through the use of a single, preloaded bellows that is restrained by a preloaded stop means preferably including a preloaded mechanical spring. The bellows remains stationary when the differential pressure transmitter is exposed to a normal, operational differential pressure. When an overrange pressure is applied to the transmitter, the bellows expands or contracts to accommodate the liquid displaced by either of the isolation diaphragms thereby protecting the transducer from the overrange pressure. Upon removal of the overrange pressure condition, the protection apparatus automatically resets itself.