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:
Nov. 01, 1977
Filed:
Jul. 21, 1976
Otis A Johnston, League City, TX (US);
Western Geophysical Co., Houston, TX (US);
Abstract
A seismic signal source apparatus is mounted on the bed of a vehicle by means of a support structure. The apparatus includes a base plate coupled to ground surface beneath the vehicle as well as a seismic signal transducer to inject sweep signals into the ground through the base plate. A restraining means is connected between the upper end of the transducer support structure and the vehicle bed to prevent rocking motion of the seismic signal source. The restraining means includes a double-acting hydraulic piston. The piston is provided with at least two spring-loaded, oppositely-directed check valves. The spring loaded valves open to allow the transducer base plate to adjust itself to the local ground contours when the transducer base plate is pressed to the ground by the weight of the vehicle. The valves remain closed during a sweep cycle to provide a rigid restraining link which prevents destructive rocking movements of the transducer and base plate during a sweep cycle.