JPH0254236B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a thermal recording device, and in particular provides a thermal recording device using a fixed head configured to eliminate accumulated wrinkles that occur during paper feeding during printing. It is something to do.

(Prior Art) A thermal recording device is also called a thermal printer, and its recording section is usually composed of a recording head and a platen roll.

The state of the combination of the recording head and the platen roll in the recording section is one where the recording head and the platen roll face each other and remain pressed and do not separate, and one where the recording head separates from the platen roll every time one page is printed. There is. However, with the former structure, the paper tends to wrinkle when it is fed during printing, and this tendency tends to become noticeable when multiple sheets of paper are set, causing scratches between the sheets. There is a drawback. Also, the latter structure is
Although the former method is improved in terms of wrinkle generation, it has the disadvantage that a large number of wirings connected to the recording head are bent and stretched each time the recording head is moved, resulting in fatigue.

(Problem to be Solved by the Invention) The present inventors have proposed a method that completely prevents wrinkles from occurring when paper is fed during printing even when a set of multiple sheets of paper is used, and also provides a method for wiring the recording head. It is an object of the present invention to provide a thermal recording device that does not cause fatigue.

(Means for Solving the Problems) In a thermal recording device such as a thermal printer, the present invention moves a platen roll that is pressed against a recording head for a predetermined short time every time a predetermined printing is completed. A platen roll is movably built into the center of the cassette-type transfer master via a spring, and the platen is pressed against the recording head of the thermal recording device. The roll is determined by multiple recording head drive signals using an OR circuit or a NAND circuit, and an electromagnetic solenoid 3 that is excited based on this determines the roll from the head for a predetermined short time every time a predetermined printing is completed. It is characterized in that it is equipped with a separation device for separating.

(Operation) The present invention will be specifically described below with reference to the drawings shown as examples.

The present invention applies a mechanism in which the platen roll 2, which is pressed against the recording head 1, is separated from the recording head for a predetermined short time every time a predetermined printing is completed. The cassette type transfer master 4 is installed in the cassette, and the platen roll 2 connected to the electromagnetic solenoid is built into the cassette. Incidentally, the reason why the cassette-type transfer master is installed in the recording head section is to enable recording on recording paper whose surface is unprocessed. That is, in order to record on such paper, it is necessary to adopt a method of overlapping masters such as carbon tape and thermally recording, and a master storage container is required for this purpose.

The reason why the platen roll is built into this cassette is to simplify the work of setting the recording paper between the head and the platen roll. That is, since the head and platen roll are normally pressed, there is a problem in that it is difficult to set the master and recording paper together between them. Therefore, if the platen roll is built into the cassette and its structure is such that when the cassette is attached to the recording head, there is a gap between the roll and the head, the master and recording paper can be set extremely easily. This is possible.

Next, the specific structure of the cassette type transfer master will be explained.

In Fig. 1, reels 7 and 7' are built into two chambers 6 and 6', respectively, and a master 8, such as a carbon tape, is wound on the reel 7 of one chamber 6 and is sequentially fed out. It is becoming more and more common. The leading end of the master is guided to a reel 7' in another chamber 6', and is wound up one after another according to the record.

The platen roll 2 is placed in the middle position between the two chambers, and as shown in FIG.
It is attached to the cassette by being supported by support stands 9 that sandwich the cassette. When this cassette is mounted on the recording head section, the platen roll 2 is arranged to be in a position corresponding to the head 1, but it cannot come into contact with the head unless it is pushed up against the spring. The operation of pressing and releasing the platen roll 2 against the head 1 after being attached to the recording head section is performed by the electromagnetic solenoid 3.

Incidentally, to explain the mechanism for pressing and releasing the platen roll 2 against the head 1 based on the control circuit shown in FIG. or
Discrimination is made by a line black/white determination circuit (B) consisting of a NAND circuit.

If there is black (recording) on part of the line, the switching circuit 2 conveys these output pulses,
The power source E is controlled to energize the winding in the electromagnetic solenoid 3. The electromagnetic solenoid 3 is thereby excited. On the other hand, when there is no pulse applied to the heat-resistant element, that is, when all lines are white (no record), the pulse from the line black/white determination circuit becomes zero, and the electromagnetic solenoid 3 is not energized, so the electromagnetic solenoid 3 is not excited.

Thus, when the electromagnetic solenoid 3 is energized or de-energized, the plunger a of the electromagnetic solenoid 3 is drawn into the electromagnetic solenoid 3, and actuates the lever b linked to the plunger a. It turns out. Therefore, when the plunger a is drawn into the electromagnetic solenoid 3, the lever b to which it is linked also moves in synchronism, and the platen roll is pressed against the head.
Conversely, when the plunger a of the electromagnetic solenoid 3 is pushed out from within the electromagnetic solenoid 3, the lever b is also pushed at the same time, and the platen roll is released from the state of being pressed against the head and separated. As a result, the recording paper running between the head and the platen roll is released from the pressurized state by the platen roll each time a predetermined recording is completed, and the wrinkles that are about to accumulate are eliminated each time. . Next, the mechanism for setting the cassette-type transfer master 4 in the recording head section and recording will be explained. First, after the cassette-type transfer master 4 is set in the recording head section, the recording paper 10 is inserted into the cassette entrance section 1 of the cassette.
1, the recording material contacts the master 8 between the guide rolls 12 and 12', is heated by the head at this position and is transferred and recorded, and is separated from the master at the exit section 13 and comes out of the apparatus.

For recording, a pressure force is transmitted to the platen roll 2 via the lever b by, for example, excitation of the electromagnetic solenoid 3, whereby the platen roll is pressed into contact with the head with the master and recording paper in between. It is done by folding. At this time, the platen roll 2 is pushed up against the repulsive force of the springs 5 and 5'.

On the other hand, when the platen roll is released and separated from the head, for example, when the electromagnetic solenoid 3 is de-energized, the lever is lowered, and the repulsive force of the spring causes the recording paper to accumulate on the recording paper traveling between the head and the platen roll. The wrinkles are eliminated each time a predetermined recording is completed by releasing the pressure between the head and the platen roll. The way the master and recording paper move during recording is that the recording paper moves continuously at a predetermined speed, so there are margins between lines and paragraphs, but for the master, the platen roll moves away from the head. When it is released, it stops moving and leaves as little unused space as possible so that it can be used effectively.

When all the masters have been wound onto reel 7', recording is temporarily stopped and reel 7' is fed out again.
To rewind the tape, either the cassette must be removed and reversed left and right, or a new cassette must be used.

(Effects) In the thermal recording device of the present invention, each time a predetermined recording of accumulated wrinkles that occur during paper feeding during printing is completed, the platen roll is released from pressure against the head by the action of an electromagnetic solenoid, and the thermal recording device This can be resolved without causing any failures.

[Brief explanation of the drawing]

FIG. 1 is a side view of a thermal recording device according to the invention of the present application. FIG. 2 is a control circuit diagram for pressing and separating the platen roll against the recording head in FIG. 1. 1... Recording head, 2... Platen roll, 3
...Electromagnetic solenoid, 4...Cassette transfer master, 5, 5'...Spring, 6, 6'...Inner chamber of cassette transfer master, 7,7'...Reel of cassette transfer master, 8...Master, 9... Support stand, 10... Recording paper, 11... Cassette entrance section, 12... Guide roll, 13... Cassette exit section, 14... Cassette installation guide, a... Plunger, b... Lever.

Claims (1)

[Claims] 1 A platen roll 2 is movably built into the center of a cassette-type transfer master 4 via a spring, and can be attached to a fixed recording head of a thermal recording device, so that the recording head 1 faces the recording head when attached. The platen roll 2 to be pressed is connected to a logical sum OR circuit or a plurality of recording head drive signals.
A thermal recording device characterized in that an electromagnetic solenoid 3, determined by a NAND circuit and excited on the basis of the determination, separates the head from the head for a predetermined short time every time a predetermined printing is completed.