JPH04197762A - Printer - Google Patents

Abstract

PURPOSE:To perform forward and backward printing with two separate print heads or selectively use the print heads so that printing amount is uniformly distributed on the print heads, by providing a main controller which selects and drives one of the two print heads at need. CONSTITUTION:A main controller 10 outputs a selective action instruction by which one of two print heads 1 and 2 is selected and driven. A selective setting circuit 10B immediately selects and turns one of switches 6A and 6B on to select one of head driving circuits 1A and 1B. On receipt of a printing instruction from a host equipment, forward printing is carried out at first by the first, print head 2. When forward printing is completed, a carrier 3 is moved in the opposite direction and backward printing is performed by the second print head 1. In the case forward and backward printings extremely differ in printing amount, the second print head 1 can be used even for forward printing and vice versa, for example, to make the printing amount uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a printer device, and particularly to a printer device having a plurality of print heads.

[Prior Art] A conventional dot serial printer has one print head equipped with a plurality of print pins, and when printing, the print head is moved, and when the print vent is at a predetermined position, the corresponding By striking an ink ribbon inserted between the paper and the print head with a printing pin, predetermined characters, numbers, etc. are printed on the paper.

[Problem to be solved by the invention]

However, in the above-mentioned conventional example, there are safety concerns when the print density becomes high and the print head becomes hot.

Since the protection sensor was activated and the printing was changed from bidirectional printing to unidirectional printing or stopped until the temperature of the print head decreased, printing efficiency was significantly reduced.

In addition, if the printing pin breaks, the quality of printing will deteriorate.
Another problem is that the printer cannot be used until the print head is replaced or repaired.

[Purpose of the invention: The purpose of the present invention is to improve the disadvantages of the conventional example, in particular, to prevent the printing speed from decreasing even when the printing density is high, and to continue printing even if a printing pin fails. The object of the present invention is to provide a don't-serial type printer device that is capable of printing.

[Means for Solving the Problem] Therefore, in the present invention, two print heads are provided on a carrier along a platen, a head drive circuit that drives each print head separately, and a head drive circuit that drives each print head separately. It has a selection setting circuit that sets the circuits simultaneously or one of them to the operating state, and operates these selection setting circuits and each head drive circuit according to commands from the host machine or an operation command input section separately equipped in advance. The main control section selects and drives one of the two print heads as necessary.

This aims to achieve the above-mentioned purpose.

(Function) Next, a case will be described in which printing is performed using separate heads for the outward and return passes based on commands from the host machine.

(2) When a printing command is received from the host device, first, the first head performs forward printing.

(2) When the printing on the outward pass is completed, the paper is fed by a predetermined pitch by the paper feed mechanism, and the printing on the return pass is performed by the second head.

(2) When the printing on the backward path is completed, the paper is further fed by a predetermined pinch by the paper feeding mechanism, and the first head performs the printing on the forward path.

(2) From then on, the above steps (2) and (2) are repeated until all print data is printed.

(2) Here, if the printing pin of the first head breaks during printing, it is also possible to print using only the second head on both the outward and return passes.

(2) When the amount of printing is extremely different between the outward and return passes, adjustments can be made such as using the second head even on the outward pass or vice versa, so that the print quantities are equal.

(3) When the temperature of one head becomes higher than the other, it is possible to rest the head with the higher temperature and use only the other head until the temperature drops.

Each of these operations is controlled by the main control section based on commands set in the main control section.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

The embodiment shown in FIG. 1 has a plurality of printing pins, and when moved to a predetermined position, the corresponding printing pin hits the paper and the ink ribbon inserted between the printing pins, thereby printing a predetermined character or character on the paper. 2 print vents for printing numbers etc.
The configuration is such that each unit is equipped with a single unit.

Here, the print head is composed of a first print head 2 that mainly prints on the forward path, and a second print head 1 that mainly prints on the return path. Also, a carrier 3 for mounting each print head 1.2 and performing spacing, a guide shaft 4 for guiding the printing operation of the carrier 3, and a platen 5 for supporting printing pressure from the back of the paper. A switch 6 is provided for selecting whether to use both print head 1 and print head 2 or to use only either print head 1 or print head 2.

The carrier 3 operates according to instructions from the main control section 10. Specifically, the carrier drive circuit 10A operates to control the movement of the carrier 3 in the outward direction or in the backward direction at a predetermined timing based on the command from the main control section 10 described above.

During operation, the main control unit 10 makes a judgment based on the output signals from the position detection sensors 20 and 21 and issues a direction change command to change the direction from the outward route to the return route.

Each print head 1.2 has a head drive circuit 1A, 2A.
is equipped with this head drive circuit IA, 2A directly.
The print head 1.2 is driven and controlled by. The operation commands to the head drive circuits LA and 2A are sent to the switch circuits 6A and 2A.
The information is transmitted by the main control unit 10 mentioned above via 6B.

Reference numeral 6 indicates a manually operated changeover switch. The main control unit 10 also outputs a selection operation command for selecting and operating one of the print heads 1 and 2.

Then, the selection setting circuit 10B inputting this command immediately selects and sets one of the head drive circuits IA and IB, so the switch 6A or 6B described above is selected and turned on (
ON).

Reference numerals 22 and 23 indicate temperature sensors, and reference numerals 24 and 25 indicate density sensors for checking print quality (print density, etc.). The main control section, which receives these sensor signals, sends predetermined signals to a display means (not shown) to display them, and functions to prompt the operator to issue predetermined commands as necessary. The specific functions of the means control section 10 in this embodiment will be explained in detail during the explanation of its operation. Reference numeral 30 indicates a paper selection control circuit for controlling means for moving printing paper.

Next, the operation of this embodiment will be explained.

(2) Upon receiving a printing command from a host device (not shown), the carrier 3 starts moving, and while being guided by the guide shaft 4, the first print head 2 first performs forward printing.

(2) When the forward printing is completed, the paper is fed with a predetermined pinch by a paper feeding mechanism (not shown), and the carrier 3 reverses its moving direction, and then moves to the second printing while being guided by the guide shaft 4.

Printing on the return path is performed by code 1.

③ When printing on the return path is completed, the paper is further fed at a predetermined pitch by the paper feed mechanism, and the carrier 3 reverses its moving direction, and while being similarly guided by the guide shaft 4, the first print head 2 prints the paper on the outward path. Printing is performed.

(2) The above steps (2) and (2) are repeated until all print data is printed.

■Here, if the printing bottle of the second printing gutter 1 breaks during printing, the first printing bottle is
, 1 By selecting printing using only second hand 2, the first printing is performed on both the outward and return trips.

Printing is performed in code 2.

Here, if the printing amount is extremely different between the outward and return passes, make adjustments such as using the second print spatula F1 even on the outward pass or vice versa, so that the print quantities are even. be able to.

Also, when the temperature of one print head becomes higher than the other, the print head with the higher temperature can be put to rest, and only the other print head can be used until the temperature drops.

[Effects of the Invention] As described above, according to the present invention, since a configuration is adopted in which a plurality of print heads are mounted, printing is performed by separate print heads for the outward and return passes, and the printing amount ratio is different for each print. The print head can be selected and used so that the nozzle is evenly distributed. Therefore, even if high-density printing is performed, the temperature of the printing material is less likely to reach a dangerous temperature range, and printing efficiency can be improved. Also,
In the event of a printing failure such as a broken printing bottle, printing can be performed using only the undamaged print head, so we provide an unprecedented don't-serial type printer device that does not interrupt the printing operation midway through. can do.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
It is a control circuit diagram of the figure. l...Second print head, IA, 2A...Head drive circuit, 2...
- First print head, 3... Carrier, 5... Platen, 10... Main control section, 10B... Selection setting circuit. Applicant Nippon Denki Co., Ltd. Agent Patent Attorney Isamu Takahashi Figure 1 1...Second print head 2...7 dollars 1A to first print, 2A...Head drive circuit 3...・Carrier 5...Platen Figure 2

Claims (1)

[Claims] (1) Two print heads installed along the platen on the carrier, a head drive circuit that drives each print head separately, and one or both of these head drive circuits to be activated. The selection setting circuit and each of the head drive circuits are operated according to commands from the host machine or a separately equipped operation command input section, and the two print heads are operated as necessary. What is claimed is: 1. A printer device comprising: a main control section that selects and drives one of the printers.