In at least some implementations, a diaphragm for a fluid pump includes a first layer formed from a first material that inhibits or prevents vapor permeation through the diaphragm, and a second layer coupled to the first layer and formed from a second material different than the first material. The first material may include at least one of fluoropolymers, perfluoroalkoxy (PFA), polyfluoroethylenepropylene (FEP), polytetrafluoroethylene (PTFE), liquid crystal polymers, nylons, thin metal foil or film, or ethylene vinyl alcohol, and the fluoropolymer may be a fluoroelastomer. The first layer may be continuous and without perforations in an area of the diaphragm adapted to be exposed to a fluid. The first layer may include a base material and a coating that prevents vapor permeation therethrough. The second material may include at least one of NBR rubber, H-NBR, NBR coated or impregnated fiber or nylon materials, or a fluoroelastomer.

Provided is a diaphragm pump including: a diaphragm that forms a part of a wall part of a pump chamber having a space for housing liquid to be delivered and that is elastically deformable to reciprocate in an inward and outward direction relative to the pump chamber; and a drive unit for elastically deforming the diaphragm toward the inner side in the inward and outward direction. The diaphragm has a lower dead point located inward of a neutral position in the inward and outward direction, in which the diaphragm is not elastically deformed at the neutral position. The drive unit is configured to support the diaphragm on an outer side in the inward and outward direction when the diaphragm lies at the lower dead point after reaching the lower dead point.

A diaphragm assembly includes a diaphragm defining a volume space; a diaphragm body extending from the diaphragm; a transition region from the diaphragm to the diaphragm body located on an outer side of the diaphragm and the diaphragm body facing away from the volume space; and a convex abutment contour arranged adjacent to the transition region. Related seat and pump assemblies are also disclosed.

Some embodiments disclosed herein are directed to a pump assembly comprising a voice coil, a magnet and a diaphragm, wherein the voice coil is configured to move the diaphragm to pump a fluid through the pump assembly in response to a drive signal applied to the voice coil. Some embodiments disclosed herein are directed to an apparatus for applying negative pressure to a wound comprising a source of negative pressure configured to be coupled to a dressing, the source of negative comprising a voice coil actuator and a diaphragm, and a controller configured to produce a drive signal for the voice coil actuator.

A multi-chamber wobble plate pump that includes a housing with an inlet port, an outlet port and a plurality of pump chambers. The pump further includes a plurality of inlet valves each located within one of the pump chambers to control fluid flow from the inlet port to the pump chambers. Each inlet valve may have an asymmetric cross-section with a thin section and/or a peripheral seal bead. The pump also includes a plurality of outlet valves that control fluid flow from the pump chambers to the outlet port and may each also have a peripheral seal bead. A wobble plate is coupled to a diaphragm and a plurality of pistons. Rotation of the wobble plate moves the pistons within the pump chambers to draw in and force fluid out of the chambers. The diaphragm may have a thin cross-sectional area that creates a hinge. The pump may further have a pulsation damper and a flexible liner located in-line with an outward flow of fluid and which absorb pressure transients and reduce noise. The pulsation dampener may be integrated into the relief valve. An elastomeric sleeve may be located adjacent to the wobble plate to provide both a seal and a noise absorber.

A diaphragm for use in a pump is provided. The diaphragm includes a flexible disc-shaped body having a first surface and an outer edge. The flexible disc-shaped body is made of an elastomer material. The fabric is applied on the first surface of the flexible disc-shaped body. And the fabric is composed of woven aramid based fibers.

A fluid handling cassette, such as that useable with an automated peritoneal dialysis (APD) cycler device or other infusion apparatus, may include a generally planar body having at least one pump chamber formed as a depression in a first side of the body and a plurality of flowpaths for a fluid that includes a channel. A patient line port may be arranged for connection to a patient line and be in fluid communication with the at least one pump chamber via at least a first one of said flowpaths, and an optional membrane may be attached to the first side of the body over the at least one pump chamber. In one embodiment, the membrane may have a pump chamber portion with an unstressed shape that generally conforms to the depression of the at least one pump chamber in the body and is arranged to be movable for movement of the fluid in a useable space of the at least one pump chamber. One or more spacers may be provided in the at least one pump chamber to prevent the membrane from contacting an inner wall of the at least one pump chamber. The patient line, a drain line, and/or a heater bag line may be positioned to be separately occludable in relation to one or more solution lines that are connectable to the cassette.

The invention relates to a diaphragm pump (109) having a pump housing (1) on which a disposable cell (2) is releasably fixable, which disposable cell has a first and a second cell wall (3, 4) which (3, 4) define an operating space (5) between them, and having an operating diaphragm (6) which (6) is drivingly connected to an oscillating stroke drive and which (6) is releasably coupleable with the flexible first cell wall (3) on its diaphragm flat side remote from the stroke drive. It is characteristic to the diaphragm pump (109) according to the invention that at least one outlet port (12) in the operating diaphragm (6) is provided with a return flow obstructer or a return flow preventer for evacuating the dead space (11) arranged between it and the first cell wall (3) (cf. FIG. 1).

The present invention provides an eccentric roundel structure for three-compressing-chamber diaphragm pump. The eccentric roundel structure is a truncated-cylinder eccentric roundel in an eccentric roundel mount. The truncated-cylinder eccentric roundel characteristically comprises an annular positioning dent, a truncated cylinder peripheral and a sloped top ring created from the annular positioning dent to the truncated cylinder peripheral to replace a conventional rounded shoulder. By means of the sloped top ring, the oblique pull and squeezing phenomena of high frequency incurred by the rounded shoulder in a conventional tubular eccentric roundel are completely eliminated. Thus, not only the durability of the three-compressing-chamber diaphragm pump for sustaining the pumping action of high frequency from the truncated-cylinder eccentric roundels is mainly enhanced but also the service lifespan of the three-compressing-chamber diaphragm pump is exceedingly prolonged.

Components for a medical infusion fluid handling system, such as an APD system, in which one or more lines (such as solution lines), spikes or other connection ports may be automatically capped and/or de-capped. This feature may provide advantages, such as a reduced likelihood of contamination since no human interaction is required to de-cap and connect the lines, spikes or other connections. For example, a fluid handling cassette may include one or more caps that cover a corresponding spike and include a raised and/or recessed feature to assist in removal of the cap from the cassette. A solution line cap may include a hole and recess, groove or other feature to engage with a spike cap and enable removal of the cap.