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:
Apr. 08, 1986
Filed:
Apr. 01, 1985
Robert R Boldt, Taylor Ridge, IL (US);
East Moline Metal Products Company, East Moline, IL (US);
Abstract
A pickup is connected to a system of sheaves of a mobile hydraulic hammer for providing a signal proportional to velocity of a hammer weight. The pickup is connected to the input of a differentiating circuit, and the output of the differentiating circuit is connected to the starting input of an electronic timer. Two-level output of the timer is connected to hydraulic valves that control the lifting and dropping of a hammer weight. The signal applied to the starting input of the timer has two states, one state resulting from any noticeable acceleration of the hammer weight and the other state resulting from zero acceleration. The timer starts in response to zero acceleration at the time of impact of the hammer weight and provides a signal to cause the hammer weight to be lifted without delay to a predetermined height according to a predetermined timing period, the height always being with reference to the level at which impact occurred. At the end of the timing period, the timer provides the other one of two signals to cause the hammer weight to drop.