A diaphragm pump is revealed. The diaphragm pump includes a pump device, a pump body, a top cover, and an air release valve head. The pump body includes at least two air inlet passages, at least one air outlet passage and at least one leak-proof/sealing passage, all selectively communicating with one cavity. The top cover includes a valve port, an air vent and an air outlet duct. Air pressure in the leak-proof passage acts on the air release valve head so that the valve port is closed by the air release valve head while the pump device is pumping air. The air release valve head and the valve port are separated from each other and then the valve port is communicating with the air outlet duct when the pump device stops pumping air. The pump performance is improved and no air release valve is required.

An electrically powered and electronically controlled diaphragm ink pump apparatus (e.g., 100, 200 or 300) and method for synchronous pressurization of ink in a corrugated board sheet feeding system comprises a diaphragm pump assembly including a reciprocating electrically driven crank mechanism connected to and driving first and second diaphragms or diaphragm surfaces, each diaphragm or diaphragm surface housed within a pump housing (e.g., 140, 240 or 340) having an ink inlet and an ink outlet in fluid communication with a manifold configured for pumping liquid ink to printing sections of a corrugated paperboard finishing machine 10 and provide a smooth reciprocating action and more uniform ink flow with reduced pressure pulsations.

A diaphragm pump such as a three-chamber diaphragm pump includes a head having an inlet port and an outlet port and defining an inlet side including inlet chambers; and an outlet side having a center outlet chamber. Each of the inlet chambers includes an associated inlet valve. A single shutoff valve controlling fluid flow to the center outlet chamber and a single bypass valve in fluid communication between the center outlet chamber and the inlet side. The single shutoff valve has a plunger with an oval cross-section extending into the center outlet chamber. The single shutoff valve and the single bypass valve have adjustable pressure set points that are adjustable independently of one another.

A diaphragm pump converts rotation of a motor into a reciprocating motion and drives a diaphragm. The diaphragm pump includes a partition configured to form a pump chamber together with a deformation portion of the diaphragm, a suction passage communicating with the pump chamber via a suction through hole extending through the partition, and a suction valve configured to open/close the suction passage. The valve body of the suction valve includes a leak structure configured to form a channel between the valve body and the seat surface of the partition.

A fluid control device includes a piezoelectric pump, a piezoelectric pump, a valve, and a container. The piezoelectric pump and the piezoelectric pump repeat the operation and the stop in accordance with a drive control cycle. The valve starts a control to close at the start timing of one cycle of the drive control cycle and starts a control to open at the stop of the piezoelectric pump and the piezoelectric pump. The time from the start timing of one cycle of the drive control cycle to the time at which the piezoelectric pump on the upstream side pump reaches a normal operation drive voltage is longer than the time from the start timing to the time at which the piezoelectric pump on the downstream side reaches a normal operation drive voltage.

A wobble plate for a sequentially activated multi-diaphragm foam pump includes three or more wings, a wobble plate shaft, and an aperture located in each of the three or more wings. A first wing is configured to have a first distance from first contact surface of a first pump diaphragm. A second wing is configured to have a second distance from a first contact surface on a second pump diaphragm, and a third wing is configured to have substantially the second distance from a first contact surface on a third pump diaphragm.

A piston for a pump and a pump are provided. A piston bladder (2) of the piston is cylindrical in shape, a chamber (20) is a cylindrical chamber, the chamber (20) has as inner diameter of 9.2±0.5 mm, the chamber (20) has a depth of 3.8±0.5 mm, the piston bladder (2) has a wall with a thickness of 0.5±0.3 mm, and the piston bladder (2) has an outer circumferential surface, a part of the outer circumferential surface connected to a base plate (1) protrudes outwards radially to form a protective sleeve (21).

A piston for a pump and a pump are provided. A piston bladder (2) of the piston is cylindrical in shape, a chamber (20) is a cylindrical chamber, the chamber (20) has as inner diameter of 9.2±0.5 mm, the chamber (20) has a depth of 3.8±0.5 mm, the piston bladder (2) has a wall with a thickness of 0.5±0.3 mm, and the piston bladder (2) has an outer circumferential surface, a part of the outer circumferential surface connected to a base plate (1) protrudes outwards radially to form a protective sleeve (21).

A diaphragm pump has at least one pump chamber, the pump chamber being connected to an inlet chamber via an inlet valve and to an outlet chamber via an outlet valve. The inlet valve has an inlet opening which can be closed by an inlet valve body, and the outlet valve has an outlet opening which can be closed by an outlet valve body. The outlet opening surrounds the inlet opening, or the inlet opening surrounds the outlet opening.

Disclosed is a valve-less micro pump configuration that includes plural micro pump elements, each including a pump body having a compartmentalized pump chamber, with plural unobstructed inlet ports and outlet ports and a plurality of membranes disposed in the pump chamber to provide compartments. The membranes are anchored between opposing walls of the pump body and carry electrodes disposed on opposing surfaces of the membranes and walls of the pump body.