JPH02243372A - Heat transfer recorder - Google Patents

Abstract

PURPOSE:To obtain a heat transfer recorder excellent in a color reproducibility by setting the carrying speed of an ink sheet faster than that of a recording paper and by causing a recording paper carrier means to differ from an ink sheet carrier means in the drive timing. CONSTITUTION:During a transfer process, a stepping motor 30 is driven and a paper discharge roller 12 and a platen roller 35 are driven to rotation. Further, the reduction ratio of pulleys 34, 35 is set so that said paper discharge roller 12 is faster than said platen roller 5, thereby giving a stale back tension to a recording paper and preventing the crumple and oblique movement of said recording paper 11 by its sagging. On the other hand, an ink sheet carrier system also uses one stepping motor 41 and the reduction ratio of pulleys 45 and 46 is set so that an ink sheet take-up roll 9 rotates faster than an ink sheet carrier roller 7. Therefore, the ink sheet carrying speed of said ink sheet carrier system is set about 6% faster in comparison with the recording paper carrying speed of a recording paper carrier system. Then, even if an ink sheet 2 expands by heat on the discharge side of a thermal head 4 pressure welding part, it is possible to avoid the generation of crumples and defective carrying due to sagging of the ink sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a thermal transfer recording device that performs multicolor recording according to image information.

(b) Conventional technology As seen in Japanese Unexamined Utility Model Publication No. 62-85443, etc., in a device that heats ink on an ink sheet with a thermal head, melts it, and transfers it onto recording paper, ink of multiple colors is layered. When expressing multiple colors, excellent recorded image quality can be achieved by ensuring that the transferred ink is fixed on the recording paper.

(c) Problem-m to be solved by the invention is that the ink sheet and the recording paper are transported at the same speed. However, the heat of the thermal head causes the ink sheet to stretch, substantially slowing down the conveyance of the ink sheet and causing wrinkles. Wrinkles on the ink sheet cause poor transfer. Therefore, in order to prevent wrinkles, it is necessary to provide a tension applying mechanism or the like, which makes the device complicated.

In addition, when the recording paper and the ink sheet are separated after the ink resin has been melted and cooled and solidified, the adhesive force when solidified prevents the ink from being transferred to the recording paper, causing the so-called transfer of the recording paper. Sticking occurs. Especially if the recording paper and ink sheet are driven at exactly the same timing,
The start of movement for both is the same, and there are drawbacks such as ink assimilation occurring before peeling and sticking easily occurring.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a thermal transfer recording device with good color reproducibility.

(d) Means for Solving the Problems The present invention transports a recording paper and an ink sheet in a stacked manner between a thermal head and a platen roller, and drives the thermal head to generate heat to remove ink on the ink sheet. A thermal transfer recording device for transferring images onto a recording paper, comprising: a recording paper conveyance means for conveying the recording paper; an ink sheet conveyance means for conveying an ink sheet; and a control means for controlling driving of the recording paper conveyance means and the ink sheet conveyance means. The present invention is characterized in that the conveyance speed of the ink sheet is set faster than the conveyance speed of the recording paper, and the drive timings of the recording paper conveyance means and the ink sheet conveyance means are made different.

(E) Function According to the present invention, ink sheet burn-in occurs due to local concentrated heating of the recording paper and the ink sheet, and the state in which the ink sheet and the recording paper stick together even when moving to the next transfer line can be prevented. This can prevent the problem of the next line not being transferred due to continuous transfer. Furthermore, since it is possible to prevent the registration from suddenly stopping due to the occurrence of stick-slip, it is possible to faithfully express the recorded image quality according to the recording signal.

(F) Example Hereinafter, an example of the present invention will be described with reference to the drawings. first,
A thermal transfer recording apparatus/device to which the present invention is applied will be explained with reference to FIG. FIG. 1 is a schematic side view.

The ink sheet (2) drawn out from the ink sheet roll (1) has the number of colors of ink in its longitudinal direction, and passes through the guide shaft (3) to the sheet conveyance roller (7) and the pinch roller ( The winding roll (9) is reached through the opposite connection with the winding roll (9). On the other hand, the recording paper (11) pulled out from the recording paper roll (10) installed between the - pair of holding reels passes through the gap between the platen roller (5) and the thermal head (4), and passes through the paper ejection roller. (12)
The paper passes through the gap between the paper and the pinch roller (13), is cut by the cutter device (14), and reaches the discharge port. The thermal head (4) is attached to the platen roller (
5), and the cam (20) controls the movement of the thermal head (4) and the platen roller (5) toward and away from each other.

Each of the above-mentioned parts includes a pair of fixed side plates (21), a pair of fixed side plates (21), slightly inside and parallel to these fixed side plates, and a shirt l-
A pair of movable side plates (
23). Between the pair of fixed side plates (21), there is an ink sheet roll (1) and a platen roller (5).
, thermal head (4) and its surroundings, conveyance roller (
7), take-up roll (9), recording paper roll (lO), conveyance roller (12), pinch roller (13), and cutter device (
14) is sorbed.

A guide shaft (3) is located between the pair of movable side plates (23).
, a thermal head (4), a pinch roller (8), etc. are absorbed.

Since the above-mentioned apparatus transfers a plurality of colors, the recording paper (11) is rewound. Furthermore, at the start of printing, the above-described apparatus reciprocates the recording paper (11) and the ink sheet (2) one page at a time so that all colors follow the same transport path.

The thermal head (11) is brought into pressure contact with the platen roller (5) to carry out normal conveyance, and in the separated state, the recording paper (11) and the ink sheet (2) are rewound independently.

Figures 2 and 3 show perspective views of the main parts of the conveyance system;
The figure shows an ink sheet conveying system, and in FIG. 3, the recording paper and the ink sheet are conveyed by separate drive sources.

As shown in FIG. 3, the recording paper conveyance system uses one stepping motor (30), and a pulley (31) attached to this motor (30) and a paper ejection roller (12) are used. A belt (33) is wound between the pulley (32) and the pulley (32). A belt (36) is then wound between a pulley (34) that is not attached to the paper discharge roller (12) and a pulley (35) that is not attached to the platen roller (5).

Furthermore, a bell) is attached to this pulley (35) and a pulley (37) attached to the holding reel of the recording paper roll (10), respectively.
(38) is wound. Further, torque limiters (391 (401) are installed in the paper ejection roller (12) and the holding reel of the recording paper roll (10), respectively.
During transfer, the stepping motor (30) is driven, and the paper discharge roller (12) and platen roller (35) are rotationally driven. Then, the paper ejection roller (12) and the platen roller (
5) so that the paper ejection roller (12) is faster.
The reduction ratio of the pulleys (34) and (35) is set, and the recording paper (II) is set using the torque limiter (
40) and the platen roller (5) and paper ejection roller (
12) provides stable pack tension to the recording paper, thereby preventing wrinkles and skew due to slack in the recording paper (11).

On the other hand, as shown in Fig. 2, the ink sheet conveyance system also uses one stepping motor (41), and the pulley (42) attached to this motor (41) and the ink sheet conveyance roller (7) A belt (44) is wound between the pulley (43) and the installed pulley (43). A pulley (46) is attached to the ink sheet take-up roll (9) via a torque limiter (48), and the pulley (46) attached to this pulley (46) and the ink sheet transport roller (7) 45
) is wrapped around the belt (47). The reduction ratio of the pulley (45) and the pulley (46) is set so that the take-up roll (9) rotates faster than the ink sheet conveyance roller (7).

Now, in the present invention, the ink sheet conveying speed of the ink sheet conveying system is set higher than the recording paper conveying speed of the recording sheet conveying system mentioned above. In this embodiment, the conveyance speed of the ink sheet conveyance system is set to be approximately 6% faster than that of the recording paper conveyance system.

Thus, even if the ink sheet (2) is stretched due to heat on the discharge side of the pressure contact portion of the thermal head (4), wrinkles and poor conveyance due to sagging of the ink sheet (I) can be avoided.

FIG. 4 is a schematic diagram showing the conveyance system of the present invention, in which a control signal from a control circuit (hereinafter referred to as CP) (50) is transmitted to a step motor (30) via an interface (51).
(41) are applied to the drive circuits (52) and (53), and at the same time, an application pulse is applied to the drive circuit (54) of the thermal head (4) wrapped around the recording signal. When the transfer is completed, a cutting signal is given to the drive circuit (55) of the cutter device (14), and the cutter device (14)
1) is cut and discharged from the discharge port.

FIG. 5 is a timing chart showing the driving timing for stepping (301 (411). When transfer starts, the applied pulse is applied to the thermal drive circuit (54).
) given to 5 so 1. A drive pulse is applied to the step motor (30) of the recording paper conveyance system. Then, a drive pulse whose timing is shifted from that of the step motor (30) is applied to the step motor (4I) of the ink sheet conveyance system. In this way, by shifting the timing of the drive pulses applied to both step modes (301 (41) during transfer, device resonance is prevented. Also, since the conveyance of the ink sheet and recording paper differs immediately after the start of conveyance, , the two can be reliably separated, and the ink on the ink sheet can be reliably transferred to the recording paper.

It goes without saying that the amount of this timing shift is not limited to what is shown in the figure and may be set as appropriate. Here, it is also possible to transport the ink sheet by driving a DC motor without using a stepping motor, and by shifting the driving timing. With the above, sticking and registration can be improved.

(g) As described in detail, according to the present invention, it is possible to prevent the occurrence of wrinkles on the ink sheet, improve transfer defects caused by wrinkles, and ensure that the ink sheet and recording paper are not peeled off. The transfer can be performed well. Furthermore, the noise caused by the resonance of the conveyance system can be reduced.

[Brief explanation of drawings]

The drawings relate to one embodiment of the present invention, and FIG. 1 is a schematic side view;
FIG. 2 is an oblique view showing an ink sheet transport system, FIG. 3 is a perspective view showing a recording paper transport system, FIG. 4 is a schematic diagram showing the structure of the present invention, and FIG. 5 is a timing chart. 1... Ink sheet roll, 2... Ink sheet,
4... Thermal head, 5... Platen roller, 7
... Ink sheet conveyance roller, 8 ... Pinch roller, 9 ... Winding roll, 10 ... Recording paper roll, 1
1... Recording paper, 12... Conveyance roller, 13... Pinch roller.

Claims (1)

[Claims] (1) In a thermal transfer recording device, a recording paper and an ink sheet are overlapped and conveyed between a thermal head and a platen roller, and the ink on the ink sheet is transferred onto the recording paper by driving the thermal head to generate heat. The recording paper transporting means transports the paper, the ink sheet transporting means transports the ink sheet, and the control means controls driving of the recording paper transporting means and the ink sheet transporting means,
A thermal transfer recording apparatus characterized in that the conveyance speed of the ink sheet is set higher than the conveyance speed of the recording paper, and the drive timings of the recording paper conveyance means and the ink sheet conveyance means are made different.