JPH0363149A - Thermal printer - Google Patents

Abstract

PURPOSE:To accurately position a member to be transferred without necessity of a complicated driving system for feeding normally and reversely by feeding the member in a feeding direction or reversely at the time of heat transfer by means for feeding the member to discharge it when the member is discharged after thermal transferring. CONSTITUTION:Recording sheet conveying roller pair 14a, 14b of a pair of pinch rollers 14a and a driving side roller 14b are provided before an inlet of two sets of recording sheet discharge passage 13. The roller 14a of one set of roller pair released during printing holds a recording sheet 6 to press it in contact with the driving side roller 14a. The pairs 14a, 14b are rotated in a direction indicated by an arrow F. The sheet 6 is conveyed as the pairs rotate, and wrinkled. Then, the pairs 14a, 14b start to rotate in reverse direction of the arrow F, and the sheet is held by conveying roller pair 15a, 15b and discharged by the rotation. Thus, the sheet can be smoothly discharged.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an improvement of a recording paper feeding device for a thermal printer.

[Prior Art] FIGS. 7 and 8 show side views of a paper feeding mechanism of a conventional thermal printer. The recording paper 6 is fed one by one from the paper supply mechanism io (see FIG. ii), the leading edge of the recording paper is inserted into the clamper 9, the clamper is closed by the clamper opening/closing mechanism 11, and the recording paper is gripped by the clamper 9. The clamper 9 is attached to a bridge 9a extending between the timing belts 3.3 in parallel with the platen roller l. Therefore, the timing belt 3.
According to the rotation of 3, the first boot 92 and the second boot 92 follow the direction of arrow A.
It returns to the initial position via pulley 4 and third pulley 5. During this time, the recording paper held by the clamper 9 is pressed by the thermal head 8 and the platen roller l, and the ink sheet 7 (the first
(see figure) will be transferred. Particularly in the case of color printing, this type of transfer is repeated 3 to 4 times by changing the color of the ink sheet 7. In other words, the recording paper is moved over each pulley 2, 4, 5 for 3 to 4 times.
It will be rotated four times.

After the above transfer is completed, FIG. 7 1. As shown in Z, the clamper 9 allows the terminal end 6a of the recording paper 6 to be placed in the recording paper ejection path 1.
The timing belt is moved in accordance with the rotation of the timing belt in the direction A until it comes to the vicinity of the entrance No. 3. Next, the timing belt reversely rotates in direction B, which is opposite to A, and accordingly, the trailing end 6a of the recording paper 6 is guided to the recording paper ejection path 13, and a pair of recording paper ejection rollers 15 in the ejection path 13
It is sandwiched between a and 15b and is discharged.

This state is shown in FIG. At this time, when the clamper 9 reaches the position of the clamper opening/closing mechanism 11, the rotation of the timing belt is stopped and the clamper 9 is opened. Therefore, only the recording paper 6 has the recording paper ejection roller pair 15a, 15b.
The paper is discharged as the paper rotates, completing a series of color printing processes.

[Problems to be Solved by the Invention] In order to eject the recording paper as the transfer target member after the transfer is completed in the conventional thermal printer as described above, the drive system of the timing belt needs to rotate in reverse. At that time, backlash etc. make it difficult to accurately position the transferred member using the rotation of the platen or the rotation speed of the pulley, and a complicated timing belt drive system that can rotate in reverse is required. There was a problem.

This invention was made to solve the above-mentioned problems, and provides a thermal printer that accurately positions a transfer member and does not require a complicated timing belt drive system that rotates in both forward and reverse directions. The purpose is to

[Means for Solving the Problems] The thermal printer according to the present invention includes a platen roller for bringing the transfer member and the transfer material into close contact with each other, and a timing belt that runs in a constant direction at a speed substantially equal to the circumferential speed of the platen roller. , a clamper provided on the timing belt that clamps the end of the sheet-shaped transfer material; a timing belt pulley that causes the transfer material clamped by the clamper to run while touching the outer periphery of the platen roller; A means for moving the thermal head that contacts the portion that contacts the platen roller and the transfer target material when discharging them.

Equipped with:

[Operation] After thermal transfer, when ejecting the transferred member, the transferred member is
When the transferred member is discharged, the transfer member is caused to travel in the traveling direction during thermal transfer and in the opposite direction, and is discharged.

[Embodiment] FIGS. 1 to 3 show a side view and a plan view of essential parts of a paper feeding mechanism in an embodiment of the present invention.

In the figure, the two left and right timing belts 3, 3 are stretched by three boots 9-2, 4 and 5, respectively, and the left and right timing belts are driven at a constant speed in the direction shown by arrow A. A clamper 9 is provided on a bridge 9a that is fixed to each timing belt 3 at both ends thereof at right angles to the running direction of the two timing belts 3.

The platen roller I is supported coaxially with the pulley 2, and its circumferential speed is made substantially equal to the running speed of the timing belt. The thermal head 8 is configured to contact or separate from the platen roller l by a mechanism not shown, and is configured to contact the platen roller 1 only when transferring to the recording paper 6 as a transfer target member. . An ink sheet 7 serving as a transfer member is supplied from a supply roller 7a, passes between a platen roller 1 and a thermal head 8, and is wound up by a take-up roller 7b. Two pairs of recording paper conveying rollers 14a and 14b, each consisting of a pair of pinch rollers 14a and a driving roller 14b, are provided in front of the recording paper discharge path 13. However, the pinch roller 14a is normally moved in the direction of arrow C by the Tsureroid 16, and the pinch roller 14a is
A sufficient gap is maintained between the roller 14b and the drive roller 14b for the clamper 9 to pass through.

Next, the operation of this embodiment will be explained. In FIG. 1, recording paper 6 is fed one by one from a paper supply mechanism 10, and its leading end is inserted into a ramper 9 by a paper feed mechanism. Next, the clamper is closed by the clamper opening/closing mechanism 11, and the recording paper 6 is gripped by the clamper 9. Next, the timing belt 3 starts running in the direction shown by arrow A, and along with this, the clamper 9 provided on the bridge 9a similarly starts running. At this time, the thermal head 8 is at a position moved in the direction shown by arrow E,
It is separated from the platen roller l, and the clamper 9 passes through the gap. After passing the clamper, the thermal head 8 moves in the opposite direction of the arrow E and comes into contact with the platen roller 1 with the recording paper 6 in between, and as the platen roller 1 rotates, printing begins. That is, the recording paper is conveyed in the direction of arrow A while ink is transferred onto the recording paper 6 by the thermal head 8 from the ink sheet 7 that is in close contact with the recording paper 6. This state is shown in FIGS. 2 and 3. By the time the clamper 9 reaches the vicinity of the clamper opening/closing mechanism 11 via the second boot 9-4 and the third pulley 5, the first transfer onto the recording paper 6 has been completed, and the thermal head 8 has It moves in the opposite direction to the direction shown by arrow E and separates from the platen roller l. The timing belt 3 further travels in the direction shown by the arrow A, and the clamper 9 again passes through the gap between the thermal hept 8 and the platen roller l and returns to the printing start position. Therefore, the recording paper 6 clamped by the clamper 7 also returns to the printing start position.

During this time, the ink sheet 7 is set up for the next color. Next, the thermal head 8 moves in the direction of the arrow E, comes into contact with the platen roller I with the recording paper 6 in between, and moves the timing belt 3 in the direction of the arrow A. At this time, thermal transfer of the second color is performed on the recording paper 6 in the same manner as printing of the first color. In this way, for example, when performing three-color thermal transfer, the recording paper 6 rotates three times together with the timing belt 2, and color printing is completed. When printing is completed, the clamper 9 should reach the vicinity of the clamper opening/closing mechanism 11 as shown in FIG.
has not reached the entrance of the recording paper discharge path 13.

Next, the pinch rollers 14a of the pair of recording paper conveyance rollers, which were separated during the aforementioned printing, are moved by the solenoid 16 in the direction indicated by the arrow. That is, the pinch roller 14a presses against the driving roller 14a with the recording paper 6 interposed therebetween. Next is the drive roller! A pulse motor (not shown) or the like that rotates the recording paper conveying roller pair 14a and 14b rotates in the direction shown by arrow F.

At this time, the clamper 9 remains stopped, that is, the timing belt remains stopped. The recording paper 6 is conveyed in accordance with the rotation of the pair of recording paper conveyance rollers 14a and 14b, and is deflected as shown in FIG. The conveyance distance of the recording paper corresponding to this deflection is controlled by inputting a pre-calculated number of pulses to the pulse motor. That is, the pulse motor is rotated so that the conveyance distance corresponds to the distance by which the trailing end 6a of the recording paper can reach the vicinity of the entrance of the recording paper discharge path 13. Next, the recording paper discharge roller pair 14a, 14b starts rotating in the opposite direction of arrow F.

At this time, since the recording paper ejection passage 13 is arranged as shown in the figure, the terminal end 6a of the recording paper is located in the recording paper ejection passage 13.
Guided within. As a result, the recording paper is sandwiched between a pair of recording paper discharge rollers 15a and 15b provided in the recording paper discharge passage 13, and is discharged by the rotational movement thereof as shown in FIG. During the above period, the clamper opening/closing machine 1
11 to release the leading edge of the recording paper. By the above-described operation, the recording paper is smoothly ejected.

[Effects of the Invention] As described above, according to the present invention, the transfer target member after thermal transfer is discharged by means for moving the transfer target member when discharging the transfer target member. Therefore, the timing belt that runs the transfer target member during thermal transfer runs the transfer target member only in a single direction, eliminating the need for a complicated drive system that runs the transfer target member in both forward and reverse directions. Furthermore, it is therefore possible to position the transferred member with high precision.

[Brief explanation of drawings]

Fig. 1 is a side view showing an embodiment of the present invention, Fig. 2 is a side view showing the printing state, Fig. 3 is a plan view of the state shown in Fig. 2, and Fig. 4 is the state when printing is completed. A side view, FIG. 5 is a side view showing how the recording paper is bent due to the rotation of the pair of recording paper transport rollers, and FIG. 6 is a side view when the recording paper is ejected.
7 and 8 are side views of a recording paper feeding mechanism of a conventional thermal printer. In the figure, 1 is a platen roller, 2, 4, 5 is a pulley, 3 is a timing belt, 6 is a recording paper, that is, a member to be transferred,
7 is an ink sheet, that is, a transfer material, 8 is a thermal head, 9 is a clamper, and 14a and 14b are a pair of recording paper conveyance rollers. Agent Daikichi Masuo 1. Nibraten roller 2. 4, 5: No. 3: Timing belt seat 6: Recording system (detection transfer member) 7. Ink sheet (skewer copying) , Nedai) 8 Thermal head 9: Clampers 14a, 14b: Yoshiki 4 East paper conveyance rollers vs. No. 1 book (self-produced)

Claims (1)

[Claims] (1) A platen roller for bringing the transfer material into close contact with the transfer material, a timing belt that runs in a fixed direction at a speed substantially equal to the circumferential speed of the platen roller, and a timing belt that is installed on the timing belt to hold the sheet-shaped transfer material. A clamper that clamps the end, a timing belt pulley that allows the transferred material clamped by the clamper to travel while touching the outer periphery of the platen roller, and a thermal head that contacts the portion of the transferred material that comes into contact with the platen roller when performing thermal transfer. Means for running the transfer member when discharging it. A thermal printer equipped with