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:
Jun. 28, 1977
Filed:
Jun. 21, 1976
Eugene A Farrell, Fishers Landing, NY (US);
Frink Sno-Plows, Clayton, NY (US);
Abstract
An operating and shock cylinder assembly for vehicle mounted underbody scraper and grader blades, plows and the like. The assembly of cylinders operates with hydraulic fluid and air, both under pressure, to move the blade or plow between retracted and road engaging positions. It also permits the blade to trip or yield when it engages a fixed obstacle in the road after which the blade quickly returns to its road engaging position. The assembly includes a pair of coacting cylinders which are first charged with air under pressure after which one of the cylinders is charged with hydraulic fluid under pressure. The hydraulic charge forces all of the air into the other cylinder and further compresses it, and this air operates as a powerful spring force or load on a piston in the cylinder that is connected to the pivotally mounted blade. Under this condition, the blade is firmly but yieldably biased into road engaging position. When not in use, the blade can be retracted by exhausting the compressed air from the air loaded cylinder and moving its piston by hydraulic fluid to lift the blade out of contact with the road.