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:
May. 13, 1997
Filed:
Dec. 01, 1994
Stewart J Mills, Essex, GB;
Kenneth C Henderson, London, GB;
Sortex Limited, London, GB;
Abstract
A valve device is disclosed for controlling the delivery of gas from a pressurised source suitable for use in a pneumatic ejector in particle sorting apparatus. It uses a diaphragm as a valve member disposed over an output port from a chamber which is in substantially continuous communication with a source of gas or air under pressure. Both sides of the diaphragm are exposed to pressurised gas or air in the chamber. For this reason, and because the diaphragm itself engages the output port to close it, when the input pressure is applied there is a differential pressure which elastically deforms the diaphragm to close the output port. The diaphragm has a piezoelectric element, and the valve device includes an electric circuit operable to selectively activate the piezoelectric element and withdraw the valve member from the output port to admit pressurised gas or air thereinto.