Part-I - Controller General of Patents Designs and Trademarks

(12) PATENT APPLICATION PUBLICATION (21) Application No.101/CHE/2012 A
(19) INDIA
(22) Date of filing of Application :10/01/2012 (43) Publication Date : 21/06/2013
(54) Title of the invention : VALVE CONTROL VALVE CIRCUIT FOR OPERATING A SINGLE ACTING HYDRAULIC
CYLINDER
(51) International classification :F15B
(31) Priority Document No :13/006123
(32) Priority Date :13/01/2011
(33) Name of priority country :U.S.A.
(86) International Application No
:NA
Filing Date
:NA
(87) International Publication No : NA
(61) Patent of Addition to Application Number :NA
Filing Date
:NA
(62) Divisional to Application Number
:NA
Filing Date
:NA
(71)Name of Applicant :
1)HUSCO INTERNATIONAL, INC.
Address of Applicant :2239 PEWAUKEE ROAD,
WAUKESHA WI 53187 U.S.A.
(72)Name of Inventor :
1)GREENWOOD, JASON
2)RADES, MATTHEW J.
3)SCHEDGICK, DAVID J.
(57) Abstract :
A system for operating a single acting hydraulic cylinder includes a directional valve that has one extreme position in which a
workport is connected to a tank return conduit, another extreme position where the workport is connected to a pump supply
conduit, and a closed intermediate a position where the workport is disconnected from both the pump and the tank. The directional
valve is pilot operated and is biased toward the one extreme position by a spring. An electrically operated primary applies pilot
pressure to the directional valve alternately from the pump supply conduit and the tank return conduit. A pilot operated check
valve has a first state which restricts fluid flow only from the workport toward the chamber and a second state in which fluid can
flows from the chamber to the workport. The system has a pressure compensation that also provides self priming of the directional
valve.
No. of Pages : 33 No. of Claims : 26
The Patent Office Journal 21/06/2013 13779