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:
Sep. 05, 1995
Filed:
Feb. 16, 1994
Applicant:
Inventors:
Assignee:
SMC Corporation, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
F15B / ; F15B / ;
U.S. Cl.
CPC ...
13762566 ; 13759618 ; 13762569 ; 137884 ;
Abstract
In a pilot-driven spool type change-over valve, a lateral width of a valve body and sizes of each port and valve hole are efficiently determined in such a manner that flow rate or fluid per unit time reaches the highest value without substantially impairing responsiveness in order to increase ability to change over the fluid. An inner diameter of the valve hole a lateral length of an opening of the port are set to substantially the highest value as determined by lateral width of the valve body, and longitudinal diameter a of an opening of each port, i.e. length in axial direction in the valve hole, is set to such a size that a characteristic value given by a/W.sup.2 is 1.5 to 2.2.times.10.sup.-2.