IP Library › Granted Patent US 12704486
Granted Patent B2
US 12704486 · App. 18/384,843 · Granted Aug 11, 2026

Pump unit for chromatograph

Inventors: Masanori Fujiwara (Kyoto, JP); Takafumi Nakamura (Kyoto, JP); Yuki Iijima (Kyoto, JP); Kosuke Wada (Kyoto, JP)
Assignee: SHIMADZU CORPORATION
G01N30/32F04B13/00F04B53/10G01N30/20G01N2030/027G01N2030/326G01N2030/328
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Quick Facts
Patent No.
US 12704486
App. No.
18/384,843
Granted
Aug 11, 2026
Kind
B2
Abstract

A pump unit for a chromatograph includes a plunger pump and an upstream check valve. The plunger pump has a pump head and pumps a mobile phase. The upstream check valve is provided upstream of the pump head. The upstream check valve includes a flow-path portion and a temperature regulator. The flow-path portion guides the mobile phase to the plunger pump. The temperature regulator regulates a temperature of the mobile phase passing through the flow-path portion.

Claims (36)

1 . A pump unit for a chromatograph, comprising:

a plunger pump that has a pump head and pumps a mobile phase; and

a check valve provided upstream of the pump head, wherein

the check valve includes

a housing,

a flow-path portion that is provided in the housing and guides the mobile phase to the plunger pump, and

a temperature regulator that regulates a temperature of the mobile phase passing through the flow-path portion and causes the mobile phase having a constant density to be introduced into the pump head by heating the housing.

2 . The pump unit for a chromatograph according to claim 1 , wherein

the flow-path portion has a spiral shape.

3 . The pump unit for a chromatograph according to claim 1 , wherein

the housing has an inner space and contains the flow-path portion in the inner space, and

the temperature regulator is attached to an outer surface of the housing.

4 . The pump unit for a chromatograph according to claim 3 , wherein

the check valve further includes a plug that has a through hole connected to the flow-path portion and fills the inner space of the housing.

5 . The pump unit for a chromatograph according to claim 4 , wherein

the flow-path portion includes a pipe attached to the plug.

6 . The pump unit for a chromatograph according to claim 4 , wherein

an inner surface of the housing and an outer surface of the plug come into contact with each other, and

a groove that is used as the flow-path portion is formed in the inner surface of the housing.

7 . The pump unit for a chromatograph according to claim 4 , wherein

an inner surface of the housing and an outer surface of the plug come into contact with each other, and

a groove that is used as the flow-path portion is formed in the outer surface of the plug.

8 . The pump unit for a chromatograph according to claim 4 , wherein

the plug is formed of a fluororesin.

9 . The pump unit for a chromatograph according to claim 4 , wherein

the check valve further includes a seal member provided between the housing and the plug.

10 . A pump unit for a chromatograph, comprising:

a plunger pump that has a pump head and pumps a mobile phase; and

a check valve provided upstream of the pump head, wherein

the check valve includes

a flow-path portion that guides the mobile phase to the plunger pump,

a temperature regulator that regulates a temperature of the mobile phase passing through the flow-path portion,

a housing that has an inner space and contains the flow-path portion in the inner space, and

a plug that has a through hole connected to the flow-path portion and fills the inner space of the housing,

the temperature regulator is attached to an outer surface of the housing, and

the plug is formed of a material having thermal conductivity lower than that of the housing.