US 11,746,777 B2
Liquid sending device
Shinya Imamura, Kyoto (JP); and Keisuke Ogawa, Kyoto (JP)
Assigned to Shimadzu Corporation, Kyoto (JP)
Appl. No. 16/768,660
Filed by SHIMADZU CORPORATION, Kyoto (JP)
PCT Filed Jun. 20, 2018, PCT No. PCT/JP2018/023437
§ 371(c)(1), (2) Date May 30, 2020,
PCT Pub. No. WO2019/130625, PCT Pub. Date Jul. 4, 2019.
Claims priority of application No. 2017-247155 (JP), filed on Dec. 25, 2017.
Prior Publication US 2021/0172437 A1, Jun. 10, 2021
Int. Cl. F04B 53/10 (2006.01); F16K 31/06 (2006.01); F04B 7/00 (2006.01); F04B 49/22 (2006.01); F16K 31/08 (2006.01); G01N 30/32 (2006.01)
CPC F04B 53/1087 (2013.01) [F04B 7/0076 (2013.01); F04B 53/1002 (2013.01); F16K 31/0655 (2013.01); F04B 49/22 (2013.01); F16K 31/08 (2013.01); G01N 30/32 (2013.01); G01N 2030/326 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A liquid sending device comprising:
a plunger pump, which performs an intake operation of liquid to and a discharge operation of liquid from a pump chamber and in which pressure in the pump chamber in a case where the intake operation is performed is lower compared to a case where the discharge operation is performed,
a check valve that is provided at an inlet port of the plunger pump, has a spherical valve element and a valve seat on which the valve element is to be seated, and passively operates according to the pressure in the pump chamber in such a direction that the valve element is seated on or detached from the valve seat,
a pressure sensor that detects the pressure in the pump chamber; and
a controller that compares the pressure in the pump chamber detected by the pressure sensor while the plunger pump is performing the intake operation with a preset threshold value and determines that the valve element is attached to the valve seat in a case where the controller determines that the pressure in the pump chamber is equal to or lower than the threshold value,
wherein
the check valve has a valve element driver for actively driving the valve element seated on the valve seat in such a direction that the valve element is detached from the valve seat,
the liquid sending device includes a valve element drive controller for controlling an operation of the valve element driver, and
the valve element drive controller is configured to actively drive the valve element by the valve element driver in such a direction that the valve element is detached from the valve seat, only in a case where the controller detects attachment of the valve element to the valve seat.