Abstract: A back pressure sensor comprising a flexible beam having a pivot end with a pivot pin and a drive connector end with a means for engaging a pump drive. A pump actuator is connected to the flexible beam at a position intermediate the ends and connects with a positive displacement pumping member. A sensor beam is attached to the flexible beam at a connecting point spaced from said pivot end. A first capacitor plate is mounted on the flexible beam at a point which is spaced from the connecting point. A second capacitor plate is mounted on the sensor beam in a position facing and spaced apart from the first capacitor plate at a distance therefrom which permits formation of a capacitance coupling therebetween.

Abstract: A back pressure sensor for a positive displacement pump comprises at least one flexible beam having a pivot end and a drive connector end, and a pump actuator mounted between the pivot end and the drive connector end. The pump actuator connects with a positive displacement member of a pump. At least one sensor beam is connected to the flexible beam at a mounting position between the distal end and vibration damping end thereof. A first capacitor plate is mounted on the flexible beam at a position adjacent to the pivot end thereof, and a second capacitor plate is mounted adjacent the distal end of the sensor beam in a position facing the first capacitor plate at a distance which permits a capacitance coupling between the capacitor plates. A vibration damping mass is secured to the vibration damping end of the sensor beam for damping drive motion vibrations in the sensor beam.

Abstract: A disposable diaphragm pump cassette comprises a flexible diaphragm member comprising hinged, rigid plates hingingly mounted on an inflexible plate and opposed to a pumping chamber surface to form a pumping chamber. The pump includes check valve means comprising movable circular plates integrally connected with the inflexible plate by flexible, extendable webs. The flexible diaphragm member comprises at least three inflexible diaphragm plates with edges in a common plane, each diaphragm plate having at least two straight diaphragm plate hinge edges. Each diaphragm plate hinge edge is adjacent to and aligned with a second diaphragm plate hinge edge of an adjacent diaphragm plate. The adjacent edges of each diaphragm plate hinge edge and second diaphragm plate hinge edge are attached together by a flexible hinge strip.

Abstract: A hinged plate diaphragm pump comprising a pumping chamber defined by an inflexible member and a flexible member opposed thereto. The flexible member has at least three inflexible plates with edges in a common plane. Each plate has at least two straight plate hinge edges, each plate hinge edge being adjacent to and aligned with a second plate hinge edge of an adjacent plate, the adjacent edges of each plate hinge edge and second plate hinge edge is attached together by a flexible hinge strip. Preferably, the plates comprise at least one array of plates positioned about an axial center of symmetry perpendicular to the common plane. The hinged plates can be hingedly connected to a surrounding support plate and an axially central plate positioned at the axis of symmetry.

Abstract: A non-invasive, external ear canal electrode useful for transmitting sound stimulus to an ear canal and for conducting electrical signals picked up from the ear canal epidermal surface including a tube comprising electroconductive metal and having a resilient plastic foam element impregnated with an electrolytically conductive medium attached to the end to be placed in the ear.

Abstract: A disposable crimping valve assembly for parenteral solution delivery systems comprises a two-piece tubing receptor housing hingedly connected and with an irreversible snap connection which will not permit removal of the device from parenteral tubing after assembly. A back section has an integral movable pressure plate attached to the housing by integral flexible web connectors. When the movable plate is actuated toward the stationary press surface, tubing is bent over a sharp ridge element until the wall thereof contacting the sharp ridge collapses in a crimping action. The motor drive assembly provides rotational pressure to a threaded actuator engaging the back section without applying axial pressure thereto. The clamp permits manual adjustment to set flow rates when it is separated from the control housing.

Abstract: A mounting clamp particularly suited for mounting medical accessories on support poles comprises a stationary clamping surface which can be attached to an accessory housing. A cam is pivotly mounted on a trunnion connected to the stationary clamping surface has a spiral clamping surface, the stationary clamping surface and spiral clamping surface being positioned to constitute a clamping means when the clamp is in a clamping position. A spring means having one end connected to the trunnion and the other end connected to the cam is provided for biasing the cam to the clamping position. A lever pivotly mounted on the trunnion has a projection which engages the cam and causing it to pivot with the lever when the lever is pivoted to a clamp releasing position. The cam preferably has two spiral surfaces, one generated by a line parallel to the axis of rotation of the cam and the second cam surface by a line forming an angle with the axis of rotation of the cam.

Abstract: A disposable pinch valve assembly for parenteral solution delivery systems comprises a two-piece tubing receptor housing hingedly connected and with an irreversible snap connection which will not permit removal of the device from parenteral tubing after assembly. A back section has an integral movable pressure plate attached to the housing by integral flexible web connectors. When the movable plate is actuated toward the stationary press surface, tubing is pinched or crimped therebetween and the cross-section area of the flow passage through the tubing is reduced. The movable pressure plate is designed to engage a actuator connector which engages the device by turning the actuator by hand or by the use of a motor-driven actuator in an axially sliding engagement.

Abstract: A non-invasive, external ear canal electrode useful for transmitting sound stimulus to an ear canal and for conducting electrical signals picked up from the ear canal epidermal surface including a tube comprising electroconductive metal and having a resilient plastic foam element impregnated with an electrolytically conductive medium attached to the end to be placed in the ear.

Abstract: A non-invasive, external ear canal electrode useful for transmitting sound stimulus to an ear canal and for conducting electrical signals picked up from the ear canal epidermal surface comprising an electroconductive tube having a resilient annnular sensor comprising a silver conductor attached to the end to be placed in the ear.

Abstract: A non-invasive, external ear canal electrode and connector therefor useful for transmitting sound stimulus to an ear canal and for conducting electrical signals picked up from the ear canal epidermal surface. The electrode comprises an electro-conductive tube having resilient plastic foam elements attached to the end to be placed in the ear. One foam element is electro-conductive and impregnated with an electrolytically conductive medium, and the cells of the other sound absorbing elements are filled with air.

Abstract: A dual parenteral solution apparatus for delivering predetermined volumes of two solutions at predetermined flow rates with increased accuracy. The apparatus has a shut-off valve in the supplementary solution supply system which is immediately activated when the supplemental solution supply is depleted.

Abstract: A disposable pinch valve assembly for parenteral solution delivery systems comprises a two-piece tubing receptor housing hingedly connected and with an irreversible snap connection which will not permit removal of the device from parenteral tubing after assembly. A back section has an integral movable pressure plate attached to the housing by integral flexible web connectors. When the movable plate is actuated toward the stationary press surface, tubing is pinched therebetween and the cross-section area of the flow passage through the tubing is reduced. The movable pressure plate is designed to engage a actuator connector which engages the device with a motor-driven actuator in an axially sliding engagement.

Abstract: The refractive optical pressure sensor of this invention is a system for measuring the pressure of a liquid comprising a light source, a light detector and a capillary formed in a transparent solid. A refractive surface of the capillary is positioned in the light path of light from the light source. A light detector is positioned in the path of light originating from the light source which has been refracted by the refractive surface of the capillary filled with air but outside of the path of light which has been refracted by the refractive surface of the capillary filled with liquid. The inlet end of the capillary is open for communication with liquid to be monitored for pressure, and the other end of the capillary is closed or communicates with a closed reservoir. Small changes in liquid pressure change the amount of liquid in the capillary passageways, causing an easily detected change in sharply refracted light.

Abstract: An optical pressure sensor including a light source, a light detector and a capillary system positioned in the light path between the light source and detector. The capillary system inlet receives liquid from the external source to be monitored, and the outlet is closed or connects with a closed gas reservoir. Light absorbing liquid forced by liquid pressure into the capillary system absorbs a portion of light corresponding to the area occupied by the liquid. This reduces the output of the light detector in an amount functionally related to the liquid pressure.

Abstract: The reflective optical pressure sensor of this invention is a system for measuring the pressure of a liquid comprising a light source and a capillary formed in a transparent solid having a reflective surface positioned in the light path of light from the light source. A light detector is positioned in the path of light originating from the light source which has been reflected by the reflective surface of the capillary. The inlet end of the capillary is open for communication with liquid to be monitored for pressure, and the other end of the capillary is closed or communicates with a closed reservoir. If the pressure of the liquid to be monitored increases, increasing amounts of the liquid pass into the capillary passageway, blocking or reducing light flow to the light detector.

Abstract: An apparatus and a method for forming a compartmentalized flexible plastic enclosure with selectively communicable compartments utilizing a pair of plates and at least one thin plastic sheet sandwiched between the plates. One plate has a surface which is conventionally plane facing the sheet and the other plate has a surface which includes a network of ridges facing the sheet and forming a sealing edge by pressure contact. The ridges defining at least the interior compartment of the bag to be formed with gaps in the ridges for defining communication channels between the compartments and valves disposed to close the gap in one position and to open the gap in the other position.

Abstract: A precision valve assembly for controlling the flow of fluids delivered to a patient has a valve element mounted on a flexible diaphragm. A controlled actuator displaces a portion of the diaphragm surface, flexing it, and by a leverage action, moves the valve closer to or away from the valve seat.

Abstract: A parenteral solution delivery control system for housing a drip chamber and detecting drops falling therethrough. One or more light sources are employed to provide light beam transverse to the drip chamber axis and covering the cross-section of the drip chamber so that drops falling therethrough, even when the drip chamber is tilted, break a light beam. A retention bar is provided to maintain the drip chamber in proper position and to break a light beam when the drip chamber is in position, thereby preventing operation of the device when not properly assembled. A liquid level control monitor is configured to provide an energized signal when the area of the drip chamber occupied by liquid during normal operation is filled with air as a consequence of the liquid level falling to an abnormal level.

Abstract: A precision valve assembly for controlling flow of fluids to a patient having a valve element mounted on a diaphragm. At least one ball positioned in a spiral track, when moved toward the center by relative rotation of the spiral track and an opposed longitudinal track, brings a valve and valve seat together to restrict fluid flow therethrough.