Abstract: A tunable capacitor comprises a cylindrical stator having a pair of fixed terminals and a cylindrical rotor telescopically mounted in radial alignment with the stator for rotary positionable adjustments with respect thereto. The stator has a pair of axially spaced, arcuate electrodes connected with the terminals. The rotor has an arcuate electrode that extends axially a distance sufficient to overlap at least portions of the stator electrodes in selected rotary positions with respect thereto.

Abstract: A microwave oscillator has a sealed, dielectric case that encloses a dielectric resonator adjacent a circuit conductor. Discrete conductive elements are removably mounted to the exterior of the case within a magnetic field generatable by the resonator. The oscillator may be tuned by selectively removing the discrete conductive elements from the case.

Abstract: A dielectric resonator 11 is tuned by varying the magnetic flux induced into a magnetically saturable shield 12 mounted adjacent the resonator by varying the flow of current through a coil 17.

Abstract: A piezoelectric pump includes a hollow cylindrical piezoelectric crystal (12) with end bells (22) and (24) on either end defining a pump chamber (14). A resilient diaphram (32) with an offset orifice (34) provides afferent valving action and a resilient diaphram (44) with an offset orifice (46) provides efferent valving action. Connecting leads (52) and (54) allow a voltage source (56) to be periodically connected to the crystal (12) by a switch (62). A resistor (64) is disposed between one pole of the switch (62) and the connecting lead (54) to allow decay of the charge on the crystal (12). By sensing the voltage on the lead (52) during relaxation of the crystal 12, the internal load can be monitored to provide an indication of the pumping operation. Automatic monitoring is provided by a computer (104).

Abstract: A variable capacitor which is both mechanically and electrically tunable includes a mechanically operable rotor/stator capacitor combination; and either the rotor or stator portion of the capacitor comprises a piezoelectric assembly which becomes dished in response to a voltage applied thereto, resulting in an air gap being created between the rotor and stator elements, thus effecting a variable capacitance as a result of the voltage application.

Abstract: An electronic device such as a multi-turn trimming capacitor and potentiometer has two conductive elements and means for rotating one element with respect to the other. The rotating means includes a drive member coupled with one conductive element such that an angular displacement of the drive member with respect to the other conductive element imparts less angular displacement to the one conductive element with respect to the other conductive element. Rotation of the one element is achieved while sealing both elements from ambience.

Abstract: A method and apparatus of pumping a fluid by means of a piezoelectric pump is provided. All moving parts, including the valves and impeller, are piezoelectrically motivated. The preferred embodiment includes a piezoelectric ceramic tube having conductive bands adhered to the outer surface. The conductive bands and an inner surface electrode define tube regions which serve as valve and reservoir pump regions.

Abstract: An apparatus for pumping a fluid by means of a piezoelectric pump is provided. All moving parts, including the valves and core, are piezoelectrically motivated. The preferred embodiment includes a piezoelectric ceramic tube having conductive bands adhered to the outer surface. The conductive bands and an inner surface electrode define tube regions which serve as valve and reservoir pump regions. A sensing circuit senses the voltage on the outer electrodes of the innermost of the piezoelectric regions to detect the presence of faulty pumping operation. The sensing circuit utilizes the piezoelectric effect that results from internal loading of the core.

Abstract: A variable air trimmer capacitor has its annular interfitting electrodes movable axially with respect to each other by the helical threads of the rotor moving through the coils of a spring. Adjacent ones of the coils of the spring are axially offset from each other. The spring is confined in the barrel of a bushing which is of smaller diameter than the spring when in its relaxed state, and the coils of the spring are urged toward axial alignment when moved onto the threads of the rotor, thus assuring positive electrical contact between the rotor, spring and bushing.