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. 07, 1987
Filed:
Apr. 23, 1986
Tatsuo Sato, Kyoto, JP;
Shingo Takimoto, Kyoto, JP;
Shimadzu Corporation, Kyoto, JP;
Abstract
A thermal printer/plotter provided with a thermal printhead having a plurality of aligned thermal resistive elements divided into several groups for sequential driving of one group after another and simultaneous energization of the selected ones of the thermal resistive elements in each one of the groups; a DC power source having a current capacity smaller than the amount of current required for simultaneous energization of all the thermal resistive elements included in each one of the groups; a capacitor of a larger current capacity connected in parallel with the thermal resistive elements so as to discharge a sufficient amount of current to be added to the amount of current supplied by the DC power source if the latter amount is not sufficient; and control means for determining the period of time for the capacitor having been discharged to be charged again to a predetermined level in accordance with the number of the thermal resistive elements that have been energized in each one of the groups, and effecting energization of those thermal resistive elements which are to be energized in the succeeding one of the groups upon lapse of said determined period of time. Instead of the above-mentioned control means the printer/plotter may be provided with means for monitoring the charging current to the capacitor or the charged voltage thereof upon application of a drive signal to each of the groups, and effecting energization of the thermal resistive elements of the next group when the charged voltage has reached a predetermined level or there is no charging current flowing any longer.