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:
Apr. 17, 2018
Filed:
Sep. 30, 2015
Fronto Co.,ltd., Tokyo, JP;
Masato Maeda, Tokyo, JP;
FRONTO CO., LTD., Tokyo, JP;
Abstract
An object of the invention is to provide a flow rate control valve assembly capable of preventing a flow rate from varying in a direction opposite to the desired direction upon flow rate control As shown in FIG., the flow rate control valve assembly comprises a sliding shaft and a sliding cylindrical surface which fit slidably in with each other in an axial direction, and a moving mechanism for moving the sliding shaft in an axial direction. At least one of the sliding surface of the sliding shaft and the sliding cylindrical surface is provided with one or a plurality of tapered grooves having its specific area defining a fluid passage. The tapered groove is configured such that flow passage resistance increases or decreases gradually along a lengthwise direction, and a cavity formed at an end of the sliding shaft for making sure of a sliding area is formed at a site isolated or shut off from the fluid passage.