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. 16, 1981
Filed:
Apr. 05, 1979
Linde Aktiengesellschaft, Wiesbaden, DE;
Abstract
A valve for controlling the admission of gas to a cylinder of a piston-type machine, or for the discharge of gas therefrom, comprises a magnetic armature shiftable between a pair of magnetic poles formed to receive the armature with minimal radial play and with a predetermined air gap from the attracting pole in the energized condition of the coil. The energizing circuit includes an inductive proximity switch which is triggered without engagement by a metal formation on the crankshaft and applies its signal to a pulse former generating a steep-flank pulse triggering a timer to produce two rectangular voltage pulses of different durations. These pulses are applied to a gating circuit which produces a stepped signal with a high initial amplitude which is amplified and applied to a power converter energizing the coil with a corresponding current waveform. A monitoring circuit responds to deenergizing the coil to drain residual magnetism from the pole piece to enable a spring to rapidly close the valve.