Abstract: A synchronized switching delay circuit including an oscillator and multivibrator for generating a synchronized delay pulse. The oscillator is divided into three waveforms shifted in phase by 120.degree.. A 4-16 decoder receives the three waveforms and the delay pulse outputs a series of blanking pulses that blank a portion of the leading edge of each of the pulses in each of the three waveforms and their complements to provide a leading edge delay. The resulting delayed waveforms are input to a three phase bridge circuit comprised of three pairs of complementary switches. The delay enables one of the switches in each pair to completely turn off before the other switch turns on.

Abstract: Shorts adapted for use by patients in hospitals, clinics and physicians' offices. A pair of shorts are provided having a front portion (12) and rear portion (14) joined together at a crotch (20) and including a waistband (16) and identical leg portions (18) extending from the crotch substantially above the patient's knees. The rear portion contains an elongated opening (22) extending from below the waistband to above the crotch. A flap (24) secured at its lower end to the rear portion just below the opening contains a fastener (30) at the opposite end of the flap adapted to be removably fastened to a fastener (32) disposed on the rear portion above the opening whereby the flap covers the opening and can be unfastened to provide access to the patient's anal area.

Abstract: A quick disconnect heat sink includes a first longitudinal bracket having a longitudinal groove along one surface thereof and a second longitudinal bracket having a longitudinal notch along one edge thereof. A heat sink having a first tongue on one end and a second tongue on the other end is disposed between the longitudinal brackets such that the first tongue is inserted in the longitudinal groove and the second tongue rests in the notch. A movable rectangular bracket is attached to the second clamping bracket such that it retains the second tongue between the rectangular clamping bracket and the notch. A first insert is disposed on the first tongue that inserts into a first slot on the first longitudinal bracket and a second insert is disposed on the second tongue that inserts into a second slot on the rectangular bracket, the inserts and slots preventing lateral movement of the heat sink. The rectangular bracket is removable so that the heat sink can be detached.

Abstract: A method and device for measuring the optical power of the cornea is provided. The device comprises a light source to illuminate the cornea, apparatus for forming a profile image of the cornea, apparatus for measuring the actual image distance from the anterior corneal surface, processing apparatus for calculating the radius of curvature and dioptric power of the cornea and display apparatus for displaying the calculated data. The method of the present invention comprises illuminating the cornea with a light source, forming a profile image of the cornea, measuring the actual image distance from the anterior corneal surface and calculating the anterior radius of curvature and dioptric power of the cornea.

Abstract: A missing pulse detector circuit is disclosed which includes a variable frequency VCO and a digital phase comparator. The phase comparator compares the phase of the VCO reference and the phase of a driving signal that drives a synchronous motor drive package. The output of the phase comparator is input to a loop filter to provide an error signal that controls the VCO frequency and phase. A second output on the phase comparator translates a phase difference into a pulse width. The pulse width is then input to an integrator circuit to delay the leading edge thereof. This delayed pulse is then input to a Schmidt trigger which provides a switching threshold. The output of the Schmidt trigger is utilized to inhibit the operation of a synchronous motor in the motor drive package. The missing pulse detector is operable to detect rapid increases in acceleration of the driving frequency and added or deleted pulses therein.

Abstract: A DC to DC switching regulator includes a first pulse width modulator (PWM) (26) and two switching transistors (48) and (50) that are coupled to a transformer (18) to generate an output signal that has pulse widths variable in response to the PWM (26). The output of the transformer (18) is rectified to provide a regulated DC output. A second PWM (78) is provided to convert the amplitude of the regulated DC output to a stream of pulses that are input to an isolation transformer (112) by a push-pull arrangement of transistors (118) and (120). The pulse width of the pulses input to the isolation transformer (112) is variable as a function of the level of the regulated DC and the amplitude thereof is a constant referenced to the internal reference of the PWM (78). The output of the isolation transformer (112) is rectified and filtered to provide an error signal that varies in response to the pulse width of the output pulses from the PWM (78).

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: Medical suction apparatus is disclosed including in combination a rigid outer canister having a cover and a disposable semi-rigid inner liner or container. Mounting assembly means coacts with the canister and cover to seal the container within the canister. The container is a cup-like member which maintains its cup-like shape before, during and after use within the canister. A simple and efficient snap-fit mounting assembly includes an annular sealing support lid on the upper peripheral lip of the container. The lid is snap-fit mounted to the rim of the canister to support the container therefrom. This mounting also establishes a gap between the container and canister, as well as sealing such gap. The cover is snap-fit mounted to the annular lid to compress the container lip and an upper section of the container sidewall between the cover and the lid. This mounting seals the interior of the container. The lid may be released from the canister without breaking the seal between the cover and container.

Abstract: A pump (10) is disclosed for use in pumping a fluid (14) from a borehole (12) to the surface. The pump includes a first and second pumping string (20, 22) extending into the borehole and a return string (26) extending from the borehole. First and second pistons (82, 94) are slidably mounted at the ends of the first and second puming strings within the borehole, respectively for reciprocation between extended and retracted positions. First and second pumping cylinders (56, 64) are secured in fixed relation to the first and second pumping strings (20, 22) so that the first and second pistons (82, 94) are slidable therein. The pistons and pumping cylinders define first and second pumping chambers (92, 104). Each of the first and second pistons includes a gear rack (88, 100) having teeth meshing with the teeth on a stroke return gear (106).

Abstract: A method for receiving and disposing of fluids from the human body includes the steps of disposing a semi-rigid burst resistive container within a rigid outer canister and supporting the inner container such that there is a space defined between the side walls of the semi-rigid inner container and the rigid outer canister. The open end of the semi-rigid inner container is fixedly covered and the fluids from the body are received within the inner container through this cover. A vacuum is applied both to the interior of the semi-rigid inner container and the space around the periphery thereof to provide an equalized pressure on both sides thereof. When the body fluids are received within the semi-rigid inner container, both the cover and the semi-rigid inner container are removed as an integral unit for disposal thereof.

Abstract: In accordance with the present invention, a pumping unit (10) is disclosed. The pumping unit includes shell structures (20, 22) each having a diaphragm (32, 38) therein to divide the pumping chamber within the structure into first and second compartments. One-way valves permit material to travel from an inlet source to the first compartment and from the first compartment to an outlet source. Deflection of diaphrams provides the impetus to draw material to the first compartment from the inlet source and drive the material to the outlet source. The motion of the diaphrams is induced by a reciprocating piston assembly (94) within a cylinder (84). The motion acts through intermediate chambers (110, 112) filled with pumping fluid and acting on the opposite side of the diaphrams from the first compartments. This permits isolation of the piston from the material being moved to prevent contamination.

Abstract: The specification discloses a cover for protecting a hospital operating room tourniquet. A thin sheet (12) is formed from flexible, liquid impervious material and has a length sufficient to be wrapped around the limb of a patient. A pad (14) is formed along one side of the sheet in order to be wrapped around the patient's limb to perform cushioning thereto. A fastener (26-28) is attached to one edge of the sheet and is attached to another portion of the sheet in order to maintain the sheet in the desired position about the patient's limb such that a tourniquet can be placed thereover. The sheet has a width wider than the tourniquet such that a portion of the flexible sheet may be folded over the tourniquet to cover and shield the tourniquet from moisture and contamination.

Abstract: A shielded clear glass cathode substrate (44) is provided for use in an image intensifier tube of the type utilizing a clear glass cathode substrate (46). A black glass cathode substrate shield (48) is coextensive with the entire longitudinal surface of the clear glass cathode substrate (46). The black glass forming the black glass cathode substrate shield (48) has an index of refraction that is greater than the index of refraction of the clear glass utilized in the clear glass cathode substrate (46). A method is provided for producing a shielded glass cathode substrate from a mass of clear glass (52).

Abstract: An adaptive semiautomatic sewing system (10) comprises a sewing machine (12), a drive unit (42) including a variable speed motor and encoder for counting stitches sewn and for sensing the rotation of the motor, at least one material edge sensor (40) mounted ahead of the needle (22) of the sewing machine, and a microprocessor controller (51) coupled to the sewing machine controls. The system (10) has manual, teach and auto modes of operation. In the teach mode, control parameters for each seam are stored as the operator sews the initial piece. Accurate control of seam lengths and end points is achieved by initiating countdown of a variable number of final stitches responsive to detection of the material edges by the sensors (40). In dependence upon the amount of the stitch which has been sewn upon edge detection, the reverse lever (17) is moved against stop member (13) in order to reduce the length of the last stitch sewn in order to improve the accuracy of the seam end point.

Abstract: An adaptive semiautomatic sewing system (10) comprises a sewing machine (12), a drive unit (42) including a variable speed motor and encoder for counting stitches sewn, at least one material edge sensor (40) mounted ahead of the needle (22) of the sewing machine, and a microprocessor controller (51) coupled to the sewing machine controls. The system (10) has manual, teach and auto modes of operation. In the teach mode, control parameters for each seam are stored as the operator sews the initial piece. Accurate control of seam lengths and end points is achieved by initiating countdown of a variable number of final stitches responsive to detection of the material edges by the sensors (40). In one embodiment, a window is set up around the stitch count at which terminal countdown initiates to avoid spurious signals. In another embodiment, momentary toggles of the sensors (40) are ignored so that an even wider range of sizes can be sewn with the same taught program.

Abstract: A device for locating leaks in a pipe includes a leak locator probe (139) that is suitable for being transported along a length of pipe. The leak locator probe (139) includes a tube (148) that is closed at one end and open at the other end. An aperture (126) provides an air flow passageway between the interior of the tube and an annular volume exterior to the tube (148) as defined by the exterior walls of the tube (148), annular rings (146) and the interior walls of the pipe. Cables (158) and (158a) are utilized to reciprocate the leak locator probe (139) within the pipe. During operation, the leak locator probe (139) is inserted into the pipe in sealing contact therewith. The pipe is pressurized adjacent the open end of the probe (139) with the annular volume between the rings (146) pressurized through the orifice. When encountering a leak adjacent the annular volume, air is caused to flow through the aperture (136).

Abstract: A pumping system (10) is disclosed for pumping a fluid (14) from within a borehole (12) to the surface. A combustion engine (18) is employed to drive a pump comprising a pump barrel (28) and an auger pump shaft (32). The pumped fluid is carried from the borehole in a fluid return tubing string (42) having a standing valve (44) therein to prevent backflow into the borehole. A fuel-air mixture is provided to the combustion engine (18) through a fuel-air tubing string (22). A byproduct of the combustion of the fuel-air mixture is heat. The combusted mixture is exhausted from the combustion engine (18) through an engine exhaust tubing string (60). The engine exhaust tubing string includes a heating coil portion (64) forming a heat exchanger to transfer heat from the combusted fuel-air mixture to the fluid (14) adjacent the inlet of the pump to reduce the viscosity of the fluid to enhance the efficiency of the pumping system.

Abstract: A screw conveyor (10) is disclosed for use in environments having a large range of temperature. The screw conveyor (10) includes a hollow shaft (12) having a number of aligned circular holes (18a, 18b) therein, with adjacent sets of holes being at right angles to each other. A stake (16) is slidably inserted in each set of holes (18a, 18b) for securing a helical flight (14a-e) to the shaft (12). Four stakes (16) are welded to the back (26) of each of the helical flights (14) along a helical line corresponding to the helical path defined by the flights (14). The slidable interaction of the stakes (16) with respect to the shaft (12) permits each flight (14) to move relative to the shaft (12) during expansion or contraction of the screw conveyor (10). The back peripheral edge (20) and front peripheral edge (22) of adjacent helical flights (14) are overlapping and movable with respect to each other to further accommodate the expansion and contraction of the screw conveyor (10).