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. 11, 2001
Filed:
Jan. 11, 2000
Craig F. Bliss, Taunton, MA (US);
Anderson, Greenwood LP, Wrentham, MA (US);
Abstract
A pressure relief valve system is provided with particular application for use in conjunction with a pressurized system containing an incompressible fluid. The system includes a main pressure relief valve in communication with the pressurized system and a pilot valve in communication with said main pressure relief valve. The pilot valve includes a pilot valve body; a pressure chamber that is always in communication with the system pressure; and a sense piston reciprocal in the pilot valve body and which is exposed to the pressure in the pressure chamber. Damping means are provided on the sense piston to improve control of the opening and closing of the valve system. Preferred damping means include at least one labyrinth damping ring that extends downward from the sense piston and is adapted to engage with an upwardly extended damping ring on a hydraulic damping plate. At least one labyrinth ring is adapted to engage at least one complimentary upwardly extending annular piston ring positioned below the sense piston so as to define a sense piston chamber which serves to provide a damping effect on the operation of the valve system.