Abstract: The bellows pump device supplies pressurized air to one air chamber of two hermetic air chambers thereby to cause a bellows to perform expansion operation to suck a transport fluid, and supplies pressurized air to the other air chamber thereby to cause the bellows to perform contraction operation to discharge the transport fluid. The bellows pump device includes: an electropneumatic regulator configured to adjust a first air pressure of the pressurized air to be supplied to the one air chamber, and a second air pressure of the pressurized air to be supplied to the other air chamber; and a control unit configured to control the electropneumatic regulator such that, at least at a time point of end of expansion during expansion operation of the bellows, the first air pressure is lower than the second air pressure.

Abstract: A bellows pump device includes first and second bellows mounted on a pump head so as to be expandable/contractible independently of each other and configured to suck a fluid from a suction passage thereinto by expansion thereof and discharge the fluid therefrom to a discharge passage by contraction thereof. First and second air cylinder portions are configured to respectively cause the first and second bellows to perform expansion/contraction operation. First and second detection devices are configured to detect expanded/contracted states of the first and second bellows, respectively. A control unit is configured to control drive of the first and second air cylinder portions on the basis of each of detection signals of the first and second detection devices such that, before one bellows comes into a most contracted state, the other bellows is caused to contract from a most expanded state.

Abstract: Provided is a bellows pump device that is able to reduce fall of a discharge pressure of a transport fluid during contraction operation of a bellows. The bellows pump device supplies pressurized air to a hermetic discharge-side air chamber thereby to cause a bellows disposed within the discharge-side air chamber to perform contraction operation to discharge a transport fluid, and discharges the pressurized air from the discharge-side air chamber thereby to cause the bellows to perform expansion operation to suck the transport fluid. The bellows pump device includes an electropneumatic regulator configured to adjust an air pressure of the pressurized air to be supplied to the discharge-side air chamber, such that the air pressure is increased so as to correspond to a contraction characteristic of the bellows during the contraction operation of the bellows.