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:
Jul. 12, 1994
Filed:
Apr. 15, 1991
Stephen Liker, Newtown, CT (US);
Trident, Brookfield, CT (US);
Abstract
Methods and apparatus are provided for preventing ink clogging in impulse ink jet printers. In preferred embodiments, the ink jet printers include at least one nozzle for ejecting ink droplets in response to a sequence of control signals and a control means unit for generating and applying the sequence to the nozzle and for controlling the amplitude of the control signals. In preferred methods, the control unit generates a plurality of mutually asynchronous firing signals on demand, the firing signals having amplitudes which are effective to eject droplets of ink from the nozzle. The control unit also generates a plurality of mutually synchronous sub-firing signals after a predetermined interval following the firing signals, the sub-firing signals having amplitudes which are effective to prevent clogging of the nozzle yet which are ineffective to eject droplets of ink therefrom.