US 11,754,066 B2
Pump system, fluid supply device and pressure detection method
Yuta Yoshii, Tokyo (JP); Chikara Sekiguchi, Tokyo (JP); Shigenori Inamoto, Tokyo (JP); Yuki Takahashi, Tokyo (JP); Daisuke Kodama, Tokyo (JP); and Daisuke Kurita, Nagano (JP)
Assigned to MINEBEA MITSUMI INC., Nagano (JP)
Filed by MINEBEA MITSUMI INC., Nagano (JP)
Filed on Dec. 22, 2021, as Appl. No. 17/645,577.
Claims priority of application No. 2020-218020 (JP), filed on Dec. 25, 2020.
Prior Publication US 2022/0205444 A1, Jun. 30, 2022
Int. Cl. F04B 49/08 (2006.01); F04B 45/047 (2006.01); F04B 49/06 (2006.01)
CPC F04B 49/08 (2013.01) [F04B 45/047 (2013.01); F04B 49/06 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A pump system, comprising:
a vibration actuator which can be electromagnetically driven;
a pair of sealed chambers connected to a suction port and a discharge port;
movable walls respectively changing volumes of the sealed chambers; and
a housing containing the vibration actuator, the pair of sealed chambers and the movable walls therein,
wherein the movable walls are displaced due to drive of the vibration actuator to respectively supply fluid in the pair of sealed chambers into a target object,
wherein pressure in the target object is detected based on a consumption current of the vibration actuator,
wherein the vibration actuator includes a shaft portion provided in the housing, a movable body supported by the shaft portion so that the movable body can perform reciprocating rotation with respect to the housing, a pair of coil core portions fixed to one of the housing and the movable body, and magnets provided on another of the housing and the movable body so as to respectively face the coil core portions,
wherein a spring mass system structure for supporting the movable body is constituted of magnetic springs formed by magnetic force acting between the coil core portions and the magnets and fluid springs formed by elastic force of compressed fluid in the pair of sealed chambers, and
wherein a drive frequency of the vibration actuator is set so as to be in a range in which the consumption current monotonically changes as the pressure in the target object increases.