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. 19, 1978
Filed:
Dec. 10, 1976
John Lloyd Paitson, Galveston, TX (US);
Marion Lonnie Parker, Houston, TX (US);
Western Geophysical Co. of America, Houston, TX (US);
Abstract
An air actuated seismic signal generator, commonly termed an air gun includes a cylindrical casing that is divided into a control chamber and a firing chamber by a sliding valve. The end face of the sliding valve that is exposed to the control chamber has a greater area than the end face exposed to the firing chamber. An air exhaust port is provided in the firing chamber; the exhaust port may be opened or closed by sliding the valve away from or towards a seat that is associated with the exhaust port. Air is admitted to the control chamber at a relatively low pressure of about 500 psi, and holds the valve in the exhaust-port-closed position because of the differential forces on the valve end faces. The firing chamber is pressurized to a relatively high pressure of about 5000 psi by a separate air supply. There is no air communication or equalization between control and firing chambers. When some of the air in the control chamber is dumped, the differential forces are upset and the sliding valve moves away from the exhaust port seat, to impulsively release the air in the firing chamber. As the piston moves away from the seat, it momentarily compresses the air remaining in the control chamber. The compressed air acts like a spring, absorbs the motion of the valve and bounces the valve back towards the exhaust port seat. At the same time a fresh supply of control air is admitted to the control chamber to finally push the valve closed again. The amount of air remaining in the control chamber and hence the 'resiliency' of the air spring can be set by means of calibrated orifices in the air dump line.