Abstract: A pump has a flexible liner which is expanded and contracted by application of positive and negative fluid pressure for receiving and discharging fluent material. The liner is received in a rigid shell which defines the maximum volume received. In discharging fluent material, a vacuum is applied to one side of the liner, while applying pressure to the other side so the liner is collapsed against the rigid shell. The liner is arranged so as to be the only part of the pump which contacts the fluent material, and is replaceable to effect rapid and easy cleaning of the pump. The liner has multiple pump cells which can expand and contract for moving fluent material through the pump cell. The pump cells can be sized and arranged so that by selection of particular pump cells which receive the fluent material, precise volumes can be metered by the pump.

Abstract: An ambulatory infusion pump (10) has a syringe barrel (16) having a fluid chamber (19) and an inner wall (22). The pump (10) further has an infusion engine (14) for moving fluid through the syringe barrel (16). The infusion engine (14) has a member (42) for engaging a portion of the syringe barrel (16) for moving the engine (14) linearly along the syringe barrel (16).

Abstract: A method for manufacturing in which a fluent material is dispensed to an article such as a container from a flexible bag The fluent material is dispensed directly to the container without any intervening structure which contacts the fluent material. Accordingly, the apparatus can be constructed of less expensive materials and does not require frequent cleaning. The apparatus acts on the bag to dispense and does not act on the fluent material. Thus, the apparatus has particular application where aseptic conditions need to be maintained such as in the packaging of the food and medicine The flexible bag is preferably formed with multiple outlets permitting simultaneous dispensing to multiple containers.

Abstract: A method and apparatus for dispensing a fluent material such as a beverage. The fluent material is dispensed directly from a flexible bag to a container without any intervening structure which contacts the fluent material. Accordingly, the apparatus can be constructed of less expensive materials and does not require frequent cleaning. The apparatus has particular application where aseptic conditions need to be maintained such as in the packaging of the food and medicine. A flow control is adapted to receive at least a portion of one flexible bag and to deform the bag to produce flow of fluent material out of the bag without contact of the fluent material by the flow control.

Abstract: A pump has a flexible liner which is expanded and contracted by application of positive and negative fluid pressure for receiving and discharging fluent material. The liner is received in a rigid shell which defines the maximum volume received. In discharging fluent material, a vacuum is applied to one side of the liner, while applying pressure to the other side so the liner is collapsed against the rigid shell. The liner is arranged so as to be the only part of the pump which contacts the fluent material, and is replaceable to effect rapid and easy cleaning of the pump. The liner has multiple pump cells which can expand and contract for moving fluent material through the pump cell. The pump cells can be sized and arranged so that by selection of particular pump cells which receive the fluent material, precise volumes can be metered by the pump. A merchandiser has a pump and a flexible bag which is deformed to selectively dispense fluent material.

Abstract: A valve is disclosed for dispensing a flowable material. The valve has a first chamber (40) at a first pressure wherein said first chamber (40) defines an outlet (28) in communication with said first chamber (40). A second chamber (42) is at a second pressure. The valve has a stop (18) indexed against a third pressure, operating to selectively place the first chamber (40) into communication with the second chamber (42). The stop (18) is operative to connect the second chamber (42) to said first chamber (40) when the first pressure is less than the third pressure.

Abstract: A valve is disclosed for dispensing a flowable material. The valve has a first chamber (40) at a first pressure wherein said first chamber (40) defines an outlet (28) in communication with said first chamber (40). A second chamber (42) is at a second pressure. The valve has a stop (18) indexed against a third pressure, operating to selectively place the first chamber (40) into communication with the second chamber (42). The stop (18) is operative to connect the second chamber (42) to said first chamber (40) when the first pressure is less than the third pressure.

Abstract: An infusion pump (10) includes a reservoir (18) containing a therapeutic liquid to be infused. The reservoir (18) includes an outlet (36) for the liquid. A volumetric air pump (24) is operatively associated with the reservoir (18) to pressurize the reservoir and thus drive liquid out the outlet (36). A valve (12) is operatively associated with the outlet (36) and prevents the flow of liquid through the outlet until a select threshold pressure is obtained in the outlet. The valve thereafter maintains an opening in the outlet that keeps the pressure in the reservoir (18) at substantially the select threshold pressure, whereby the volumetric flow rate of liquid through the outlet (36) is proportional to the volumetric flow rate of air from the volumetric air pump (24). The valve (12) varies the opening in the outlet to maintain the select pressure.

Abstract: An apparatus in a medical delivery device for biasing tubing having a select original cross-section which is subject to compression and relaxation to substantially its original cross-section upon relaxation. The apparatus includes a plurality of bumpers disposed lengthwise of the tubing operatively associated with the tubing to bias the tubing to its original cross-section and spaced relative to adjacent bumpers to provide for free expansion of the tubing as it is subject to compression.

Abstract: A liquid delivery device which controls the flow of liquid from a liquid reservoir includes a resilient tubing having a wall with a substantially cylindrical cross-section defining a flow lumen. The flow lumen is in fluid communication with the reservoir. A compression member selectively compresses a lengthwise segment of the cylindrical wall to collapse the flow lumen and releases the lengthwise segment to open the flow lumen. An elastomeric sleeve envelopes greater than half an outer diameter of the cylindrical cross-section of the resilient tubing along at least a portion of the lengthwise segment of the cylindrical wall. The elastomeric sleeve biases the lengthwise segment of the resilient tube to restore it to its substantially cylindrical cross-section when the compression member releases the lengthwise segment.

Abstract: A device for the reliable detection of air or air bubbles in transparent or translucent tubing carrying a fluid which includes a transmitter element for transmitting a light beam to the fluid contained in a large-bore thin-walled transparent tubing, and a pair of first and second light receiver devices for receiving reflected and transmitted light emitted from the transmitter element and which is incident upon the fluid conducting tubing. The light transmitter and receivers are located within a body member around the fluid conducting tubing. Also, an acrylic optical spacer which has a passage for accommodating the tubing is located within the body member. One light receiver is disposed at a 90.degree. angle in relation to the optical axis of the transmitter, while the other receiver is arranged at a 180.degree. angle. Outputs of the light receivers are applied to a processor, which processes the light receivers outputs to detect air in the tubing.

Abstract: A microprocessor controlled volumetric infusion pump is set as to volume and rate of infusion by two digipots (shaft encoders) each having sixteen detented positioned in 360 degrees. The microprocessor is programmed such that the extent to which the parameter is changed for a given rotation of its setting digipot depends on the speed with which the digipot is rotated. For slow or normal rotation, unit change in parameter is produced for each detented position traversed. Faster rotation causes the setting to jump from one to the next of a series of preselected preferred settings, irrespective of the number of detented positions traversed. The direction of rotation determines whether the setting increases or decreases.

Abstract: A device for detecting air in large bore thin walled transparent tubing, including a body providing accommodation for the tubing; an LED in a passage body for transmitting light energy towards the tubing; a phototransistor mounted in an orthogonally extending passage for receiving light transmitted by LED and modified by changes in the constituency of fluid passing through tubing; and an optical spacer in the form of a slotted collar of material optically matched to the material of tubing occupying space between LED and the tubing and phototransistor.

Abstract: A pumping arrangement including a squeezing device for deforming a length of pliant p.v.c. tubing first in one direction locally to reduce its volume and in another tending to restore its original cross-section and, on either side of squeezing device, inlet and outlet valves which operate by occluding the tubing. The squeezing device and the valves are controlled by a microprocessor control unit such that inlet valve is open and outlet valve shut while the squeezing device is relaxed and thereafter outlet valve is open and inlet valve shut while the squeezing device is operated to deform the tubing, this sequence repeating. Downstream of the output valve is a pressure responsive device providing input to the control unit whereby upon a rise in pressure in the delivery portion of tubing due to a restriction, the squeezing device is disabled and valves are open together to allow excess fluid to pass back towards the fluid source.

Abstract: An arrangement for monitoring the pressure of fluid flowing through pliant tubing forming part of a system for the intravenous supply of fluids to a patient under medical treatment in which the tubing is caused to assume an elongate cross-section and a linear voltage displacement transducer having a spring loaded plunger is arranged to apply pressure in a flattened region of the tubing wall to provide indications of contact area movement and thus variations in fluid pressure. Compensation for movement of the contact area after pressure is applied due other than to variations in pressure is provided by a sampler which regularly samples the output of tranducer and provides inputs to a comparator directly and via a shift register so that one sample is compared with an immediately preceding sample. If the difference exceeds the threshold of a threshold circuit, which is indicative of fluid pressure change, an alarm is sounded.

Abstract: A pumping device controlling an amount of liquid passing through a length of tubing accommodated in the pumping device. The pumping device includes inlet and outlet valves located adjacent opposed sides of a tube deforming device. The valves are controllable for restricting the flow of liquid through the tubing, and the deforming device is such that the tubing is first deformed in one direction and then in another direction which tends to restore the original cross-sectional shape of the tubing.

Abstract: An electrophoresis cassette system which when used with a detector can automatically perform an analysis of radio-labelled molecules. The cassette system is easily assembled and may be reused. The cassette includes a new type of side spacer which incorporates nylon monofilament and which includes a buffer zone for increased accuracy. A new clamp and other improvements further enhance the accuracy of the cassette and reduce variations in the electric field at the bottom and sides of the cell to provide increased accuracy. A new cassette filling system is shown for use with the cassette which permits rapid filling of a cassette with gel material while providing a more uniform gel layer than was previously attainable.

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 pumping device controlling an amount of liquid passing through a length of tubing accommodated in the pumping device. The pumping device includes inlet and outlet valves located adjacent opposed sides of a tube deforming device. The valves are controllable for restricting the flow of liquid through the tubing, and the deforming device is such that the tubing is first deformed in one direction and then in another direction which tends to restore the original cross-sectional shape of the tubing.

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.