US 11,939,970 B2
Control arrangement for first and second piezoelectric pumps positioned in series
Kenjiro Okaguchi, Kyoto (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Kyoto (JP)
Filed on Sep. 8, 2021, as Appl. No. 17/469,395.
Application 17/469,395 is a continuation of application No. PCT/JP2020/015392, filed on Apr. 3, 2020.
Claims priority of application No. 2019-084139 (JP), filed on Apr. 25, 2019.
Prior Publication US 2021/0404461 A1, Dec. 30, 2021
Int. Cl. F04B 43/04 (2006.01); F04B 23/02 (2006.01); F04B 41/06 (2006.01); F04B 49/06 (2006.01)
CPC F04B 43/046 (2013.01) [F04B 41/06 (2013.01); F04B 49/06 (2013.01); F04B 23/02 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A pump device comprising:
a first piezoelectric pump;
a second piezoelectric pump connected in series with the first piezoelectric pump on a downstream side of the first piezoelectric pump;
a driver configured to supply AC input power to each of the first piezoelectric pump and the second piezoelectric pump;
a controller configured to control an input power of each of the first piezoelectric pump and the second piezoelectric pump; and
a power supply configured to supply power to the driver,
wherein the controller is configured to control the input power of the second piezoelectric pump to be larger than the input power of the first piezoelectric pump based on a negative pressure in a container that is connected to an upstream side of the first piezoelectric pump.