A multistage compressor is disclosed that may include a wobbling member operationally coupled with an external power source. The external power source may drive a nutating motion of the wobbling member. The multistage compressor may further include a plurality of flexible chambers connected to the wobbling member, each flexible chamber including a respective intake passage and a respective discharge passage. The wobbling member may sequentially press down and pull up the plurality of flexible chambers. The multistage compressor may further include a one-way valve in each respective intake passage and gas may be drawn into each flexible chamber through the respective one-way valve of each flexible chamber as the wobbling member pulls up each flexible chamber. The gas may then be compressed to a higher pressure as the wobbling member presses down each flexible chamber and compressed gas may be discharged through the respective discharge passage of each flexible chamber.

An electrochemical compressor, including a first end plate, a second end plate, a voltage supply connected to the first end plate and second end plate, a plurality of membranes, where each membrane of the plurality of membranes has a substantially same impedance, and where each membrane of the plurality of membranes has a different thickness in a stacking direction, and a plurality of conductive bipolar plates, where the bipolar plates of the plurality of bipolar plates are arranged in contact with, and alternating in the stacking direction with, the membranes of the plurality of membranes, and where the membranes of the plurality of membranes and the bipolar plates of the plurality of bipolar plates are electrically connected in series between the first end plate and second end plate.

A linear-acting electric pump unit and method for operating said unit. A linear-acting electric pump unit comprises an electromagnet and a pump unit. It is to be suitable for delivering gas/liquid mixtures. In order that it may be compactly assembled with other devices, it is to have a central inlet. The fluid delivered by the pump unit flows through the electromagnet and enters the pump unit on one side and leaves it on the other through the non-return valves, each arranged on the same centre line as the electromagnet. The pump unit can be used for delivery of gas/liquid mixtures, preferably in the sphere of combustion engines and their fuel supply systems and exhaust emission control systems.

A linear-acting electric pump unit and method for operating said unit. A linear-acting electric pump unit comprises an electromagnet and a pump unit. It is to be suitable for delivering gas/liquid mixtures. In order that it may be compactly assembled with other devices, it is to have a central inlet. The fluid delivered by the pump unit flows through the electromagnet and enters the pump unit on one side and leaves it on the other through the non-return valves, each arranged on the same centre line as the electromagnet. The pump unit can be used for delivery of gas/liquid mixtures, preferably in the sphere of combustion engines and their fuel supply systems and exhaust emission control systems.

An electrochemical compressor, including a first end plate, a second end plate, a voltage supply connected to the first end plate and second end plate, a plurality of membranes, where each membrane of the plurality of membranes has a substantially same impedance, and where each membrane of the plurality of membranes has a different thickness in a stacking direction, and a plurality of conductive bipolar plates, where the bipolar plates of the plurality of bipolar plates are arranged in contact with, and alternating in the stacking direction with, the membranes of the plurality of membranes, and where the membranes of the plurality of membranes and the bipolar plates of the plurality of bipolar plates are electrically connected in series between the first end plate and second end plate.

An electrochemical compressor, including a first end plate, a second end plate, a voltage supply connected to the first end plate and second end plate, a plurality of membranes, where each membrane of the plurality of membranes has a substantially same impedance, and where each membrane of the plurality of membranes has a different thickness in a stacking direction, and a plurality of conductive bipolar plates, where the bipolar plates of the plurality of bipolar plates are arranged in contact with, and alternating in the stacking direction with, the membranes of the plurality of membranes, and where the membranes of the plurality of membranes and the bipolar plates of the plurality of bipolar plates are electrically connected in series between the first end plate and second end plate.

A breast pump according to the present invention includes a variable pressure generating unit, the variable pressure generating unit including a power driving unit including a stepping motor that is capable of rotating both normally and in reverse, and a negative pressure forming unit that creates a negative pressure state periodically by causing an elastic body to deform in accordance with a cycle period formed by the power driving unit, wherein the negative pressure forming unit is coupled to the expressing unit, and the stepping motor is capable of modifying an amplitude of the cycle period and the cycle period during negative pressure formation as desired. Hence, a suction pressure and a pressure increase/decrease cycle can both be set as desired, and moreover, a breast pump that uses electric power can be constructed compactly.

An apparatus for treating a tissue site with negative pressure having a pump and a pump actuator. The pump may include a chamber wall that may define a pump chamber. The pump actuator may include a mechanism to actuate the pump. The pump actuator may be releasably coupled to the pump. In some examples, the chamber wall may include a drive surface and the pump actuator may include a cylindrical cam having a working surface configured to engage with the drive surface of the pump. In some examples, the pump actuator may have an actuator arm configured to couple to the pump to actuate the pump. Actuation of the pump may create a negative pressure in the pump chamber that may be delivered to a tissue site.

An apparatus for treating a tissue site with negative pressure having a pump and a pump actuator. The pump may include a chamber wall that may define a pump chamber. The pump actuator may include a mechanism to actuate the pump. The pump actuator may be releasably coupled to the pump. In some examples, the chamber wall may include a drive surface and the pump actuator may include a cylindrical cam having a working surface configured to engage with the drive surface of the pump. In some examples, the pump actuator may have an actuator arm configured to couple to the pump to actuate the pump. Actuation of the pump may create a negative pressure in the pump chamber that may be delivered to a tissue site.

A tubephragm pump includes a tubephragm that has a pump head portion that forms a pump chamber, a driving head that holds the tubephragm and expands and contracts the pump chamber by directly pressing and pulling the pump head portion in a direction intersecting with a transfer direction of a transfer fluid, a driving unit that drives the driving head back and forth in a driving direction to expand and contract the pump chamber, and a control unit that controls the driving unit. The tubephragm is in a flat shape with a cross-sectional shape intersecting with the transfer direction of the transfer fluid of the pump chamber having a length in a direction intersecting with the driving direction longer than a length in the driving direction. A pair of liquid contacting surfaces opposing in the driving direction of the pump chamber move while maintaining a parallel state.