US 5,685,653 A · Method and system for controlled inking of printer ribbons

Abstract

A method and apparatus for extending the useful life of a printing ribbon by controlling the ratio of ink used to ink applied to the ribbon, while maintaining visual clarity of printed characters. A counter accumulates the number of characters printed, and the print density, over a preset period of time. The number of characters printed is compared with predetermined triggering numbers of characters, and the print density is likewise compared with a predetermined triggering print density. As a result of this comparison, the speed of the printer ribbon is increased to allow an increase in the ratio of ink applied to ink used, when the number of characters and print density are high. Conversely, ribbon speed is decreased when the number of characters printed during the preset time period, and the print density, are low, to prevent overinking and fouling of printer hammers. This condition applies when the ribbon is relatively new.

Claims26

Dependent claims

A method of controlling the amount of ink applied to a ribbon that is reinked at a rate related to the rate of movement of the ribbon through a printer, the method comprising:

(a) counting the number of characters printed using the reinkable ribbon;
(b) maintaining a total count of the number of characters printed using the reinkable ribbon;
(c) periodically comparing the total count of the number of characters printed using the reinkable ribbon with a first number of characters limit;
(d) calculating a print density by dividing the number of characters printed during a predetermined period by the total number of character positions available for printing during the predetermined period;
(e) comparing the calculated print density with a first print density limit;
and
(f) controlling the amount of ink applied to the ribbon by setting the speed of the ribbon to a value that is based on the result of periodically comparing the total count of the number of characters printed using the reinkable ribbon with the first number of characters limit and the result of comparing the calculated print density with the first print density limit.

4 more elements

In a printer that prints characters on a print receiving medium by causing print hammers to impact print elements, said impact causing said print elements to strike a ribbon and transfer ink from said ribbon to said print receiving medium, said print ribbon being inked as said print ribbon moves through said printer at a rate related to the speed of movement of said print ribbon, the improvement comprising a system for controlling the amount of ink applied to said print ribbon, said system comprising:

(a) a speed-controllable drive for moving said ribbon as said printer prints characters;
and
(b) a ribbon speed control subsystem coupled to said speed-controllable drive for controlling the rate at which said speed-controllable drive moves said ribbon through said printer as said printer prints characters, said ribbon speed control subsystem including a signal processor for:
(1) receiving and storing information about the total number of characters printed by said ribbon;
(2) periodically comparing the total number of characters printed by said ribbon with a first number of characters limit;
(3) calculating a print density by dividing the number of characters printed during a predetermined period by the total number of character positions available for printing during the predetermined period;
(4) comparing the calculated print density with a first print density limit;
and
(5) supplying a speed control signal to said speed-controllable drive mechanism whose value is based on the result of comparing the total number of characters printed with the first number of characters limit and the result of comparing the calculated print density with the first print density limit.

6 more elements

Dependencies are inferred from the claim text.

Method and system for controlled inking of printer ribbons

Life of this patent

Method and system for controlled inking of printer ribbons

Life of this patent

Abstract

Claims26