The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 10, 2026
Filed:
Jan. 28, 2021
Yoshino Kogyosho Co., Ltd., Tokyo, JP;
Hideaki Hoshino, Tokyo, JP;
Yuichi Okuyama, Tokyo, JP;
YOSHINO KOGYOSHO CO., LTD., Tokyo, JP;
Abstract
A plunger pump, including: a tubular cylinder that has an internal space communicating with inlet and outlet flow paths; and a piston that is movable along an axis of the cylinder, wherein a head of the piston includes, on an outer peripheral surface thereof, a sealing portion that is slidable against an inner peripheral surface of the cylinder, which includes a body tubular portion wherein the head is arranged during normal use, and a cleaning tubular portion wherein the head is arranged during cleaning, an inner peripheral surface of the cleaning tubular portion has an inner diameter equal to that of an inner peripheral surface of the body tubular portion, the cleaning tubular portion includes, on the inner peripheral surface thereof, at least one cleaning liquid circulation groove that is configured by a through hole or recess, and the cleaning liquid circulation groove extends obliquely with respect to the axis.