JPH0326664B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the operation of a printed body by detecting whether or not a printing member such as a printing hammer that performs a printing operation in conjunction with the action of an electromagnet performs an accurate printing operation.

Traditionally, printing hammers in line printers,
In devices such as wires in dot printers that move and print due to the action of electromagnets, even though a printing command is generated,
The electromagnet of the corresponding printing member may not work due to circuit failure or other causes, resulting in errors such as omitted printing.For this reason, in the past, error detection was performed as shown in the flowchart in Figure 1, for example. Ta. That is, when printing data (user data) is input, an electromagnet is specified to operate the printing member corresponding to the printing data, and then it is checked whether the specified electromagnet is actually energized and operated. For example, the voltage applied to the electromagnet is checked to determine whether it is an appropriate voltage sufficient to cause the printing means to perform a printing operation, and if the voltage is appropriate, that is, there is no error, the paper is fed to the next line, and the voltage is lower than the appropriate voltage. In the case of low voltage, that is, if there was an error, the printer was designed to stop immediately, but with this conventional method, the error check was performed after the printing operation, so the printing data was erased during the printing operation, so it was difficult to correct the error. When printing the same content later, it is necessary to input the print data again, which has the drawback of significantly lowering efficiency, and also has the disadvantage of wasting printed paper containing errors, increasing costs.

This invention aims to eliminate the drawbacks of the above-mentioned conventional ones.

Embodiments of the invention will be explained using drawings in a line printer.

In Fig. 2, L is an electromagnet that is separately arranged in relation to a printing hammer (not shown) and moves the printing hammer to perform printing when energized, and Tr energizes the electromagnet L connected to the collector when base current is input. A transistor conducting as, EC is the voltage Vo
This is an error detection circuit that detects (Fig. 2) and determines whether the electromagnet L is working properly. Cp is a comparator, which supplies a base current to the transistor Tr when the input voltage of the one side terminal is lower than the input voltage of the ten side terminal, and cuts off the base current of the transistor Tr when the one side is higher than or equal to the input voltage of the ten side terminal.
TS is a setting circuit that generates a low voltage signal to one side terminal of the comparator CP, and the generation time (pulse width) Δt of the low voltage signal is set separately for hammer initialization and printing. In the latter case, the electromagnet L is energized for a time Δt ₁ so that the printing hammer does not touch the paper, and in the latter case, the electromagnet L is energized so that the printing hammer moves through the paper until it touches the type. Let time be Δt ₂ (Δt ₂ >Δt ₁ ). This circuit operates based on the flowchart of FIG. 3 under the control of a CPU (not shown) of a microcomputer. That is, before receiving user data, the "Hammer Initialize" subroutine operates, and the setting circuit TS is set by a command from the CPU to generate a low voltage signal of Δt ₁ for a certain period of time, and then the detection circuit EC is activated. determines whether the normal voltage is applied to the electromagnet L, that is, whether the hammer operates normally, and sends a reply to the CPU.When an error occurs, the CPU immediately stops the printing mechanism, and when normal, prints one line. The printing data (user code) is read, and the electromagnet L is activated by the low voltage signal of Δt ₂ from the setting circuit TS to perform printing and paper feeding, and then return to hammer initialization again.

This invention has the above-described configuration, and the "Hammer Initialize" subroutine operates, and a low voltage signal of Δt ₁ is generated from the setting circuit TS and inputted to one side of the comparator CP, and from the comparator CP to the transistor Tr. A base current is supplied to the transistor Tr, which makes the transistor Tr conductive, and the electromagnet L is energized, but since the energization time (Δt ₁ ) is short, the hammer does not come into contact with the paper. The detection circuit EC checks the voltage of the electromagnet L at this time, and if the voltage is normal, it reads one line of print data, and a low voltage signal of Δt ₂ is generated from the setting circuit TS and input to one side of the comparator CP. , the transistor Tr conducts again and energizes the electromagnet L, which operates to move the hammer through the paper until it touches the type, and then processes the "Hammer Initialize" subroutine again, and similarly Repeat. In this example, the action of the electromagnet during hammer initialization and printing is controlled by the energizing times Δt ₁ and Δt ₂ , but the input voltage value to the terminal of the comparator CP is controlled. Similar control can also be performed.

Further, in this embodiment, the printing hammer means of a line printer having a plurality of hammers has been described, but it may be implemented in the wire means of a dot printer or the printing hammer means of a serial printer having a single hammer.

Also, as a method of error detection, voltages V ₀ , V ₁ ,
V ₂ and the respective times may be checked.

As described above, according to the present invention, the electromagnet energizing circuit is controlled so that the printed body is moved from the non-acting position to an intermediate position where it does not touch the printing paper and then returned to its original state, and then the electromagnet energizing circuit is After determining whether the state is normal or abnormal, the electromagnet energizing circuit is controlled to read the print data and move the print body from the inactive position to the active position where it contacts the printing paper in the normal state; By controlling the energizing circuit and keeping the electromagnet energizing circuit in an inactive state in the event of an abnormality,
Before printing, an electromagnet is energized to move the printing object such as a printing hammer or wire to a position where it does not touch the paper, and after detecting an abnormality in the device, the printing data is read and printed, so that the printing data is not affected by the printing operation. It is not erased, and in the event of an error, the error is corrected and then printing is started immediately, which greatly improves efficiency.The printing paper is not contaminated by error printing, which eliminates wasted paper, which reduces costs. Effects such as

[Brief explanation of the drawing]

Fig. 1 is a flowchart for conventional malfunction detection, Fig. 2 is an electric circuit for hammer drive and malfunction detection of this embodiment, and Fig. 3 is a flowchart for malfunction detection of this embodiment. .

Claims (1)

[Claims] 1. Control the electromagnet energizing circuit so that the electromagnet is energized with a predetermined voltage value, move the print object from the inactive position to an intermediate position where it does not touch the printing paper, and return, and then energize it to that intermediate position. After determining the normal state or abnormal state in relation to the applied voltage value of the electromagnet at the time, if the state is normal, the print data is read and the electromagnet is energized with a predetermined voltage value to move from the inactive position to the active position where it contacts the printing paper. A method for controlling the operation of a printed body, in which an electromagnet energizing circuit is controlled to move the printed body, and the electromagnet energizing circuit is held in an inactive state in the event of an abnormality.