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. 28, 1987
Filed:
May. 10, 1985
Taiji Tajima, Yokohama, JP;
Shigemitsu Higuchi, Fujisawa, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A control circuit comprises a first counter for counting up stepping pulses and counting down the number of steps of a stepping motor, a memory for storing therein a drive timing of the stepping motor, a variable timer for converting a data in the memory to a real time, a second counter for counting up an output signal of the variable timer when a count of the second counter is smaller than a count of the first counter and counting down the output signal of the variable timer when the count of the second counter is equal to or larger than the count of the first counter, and a drive circuit for driving the stepping motor in accordance with the output signal of the variable timer. Signals to set the first counter in the count-up mode and the count-down mode are synchronized with two clock signals having the same frequency and different phases. The control circuit drives the stepping motor immediately after the control pulse signal was applied to accelerate or decelerate the stepping motor so that a velocity pattern of the stepping motor is controlled in a pedestal pattern.