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:
Jan. 02, 1979
Filed:
Jul. 21, 1977
Hitachi, Ltd., , JP;
Abstract
This invention relates to a driving signal control circuit, in which at least four detecting points (or detectors) are arranged for detecting the position of the working table, which is repeatedly reciprocated between the detecting points. The control circuit includes a clock generator for generating a clock signal in accordance with a start signal, a gate circuit operative in response to detecting signals derived from the detectors when the working table has reached the detecting points, for selectively applying the clock signal as an Up output signal or a Down output signal and for providing a switching signal, a counter circuit for adding the Up output signal or for subtracting the Down output signal, a digital-to-analog converter for converting a digital output signal of the counter circuit into an analog signal, and a switching circuit operative for generating a driving signal with negative polarity or positive polarity in accordance with the switching signal and corresponding to the analog signal in value, whereby the working table can be smoothly moved by the driving signal without generating mechanical vibration in the working table.