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. 03, 2001
Filed:
Oct. 20, 1999
Timothy Lloyd Hughes, Cypress, TX (US);
John Douglas Smith, Houston, TX (US);
DTC International, Inc., Houston, TX (US);
Abstract
A pulse piloted cartridge valve that defaults to a closed position. A spring biases against a latching piston assembly within the valve to position the latching piston assembly to the closed position. In this position, a supply port is sealed off from a control port. Pressurized fluid may be provided in a pilot open chamber to move the pilot open piston downward on the upper stem of the latching piston assembly to push the latching piston assembly to an open position. When in the open position, the passageway from the control port to the supply port is opened as well as the passageway from the control port to the axial passageway. Pressure is then transferred from the supply port through the axial passageway to the latching chamber. The pilot open piston is raised by pressure from the axial passageway. The latching piston assembly is held in the open position with pressure within the latching chamber. The pressure provided to the pilot open chamber may then be removed and the latching piston remains in the open position. The pulse piloted cartridge valve of the invention may be closed by providing pressurized fluid to a pilot closed chamber or by decreasing pressure from the supply port so that the latching piston assembly will be returned to a closed position by the spring.