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. 11, 1978
Filed:
Dec. 29, 1975
Samuel B McClocklin, Owatonna, MN (US);
James C Solie, Owatonna, MN (US);
Jan H Boers, Owatonna, MN (US);
Owatonna Tool Company, Owatonna, MN (US);
Abstract
A control valve for controlling flow relative to a pair of control ports which includes a pair of 3-way valve components each having one of the control ports and a poppet valve member which, when closed in one position under pilot control, blocks pressure flow to a control port and connects the control port to reservoir, a pressure-reducing valve which initially operates to supply a relatively low pressure pilot fluid to a pilot control for the 3-way valves and, after operation of the latter, permit full line flow through a pair of branch passages each having a one-way check valve preventing return flow. Operation of the pilot control from a neutral position shifts one of a pair of pilot pistons associated one with each of the 3-way valves to move the poppet valve member of the associated 3-way valve to a position to close off the control port from line pressure and connect the same control port to reservoir and with line flow passing through a nonpiloted check valve to the other of said 3-way valves to the control port. The pilot control has a neutral control position wherein neither of the pilot pistons are actuated, with the result that each of the 3-way valves has its valve spool normally urged to a position closing off the pair of control ports from reservoir whereby, with the return flow blocked by a pair of non-piloted check valves, flow to and from said control ports is blocked and an operated device, such as a hydraulic cylinder, is locked in position.