JPH0751360B2 - Thermal recording device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal recording device using an end face type thermal head.

Configuration of Conventional Example and Problems Thereof Since the thermal recording apparatus is excellent in maintainability, many printers including facsimiles are capable of multi-color or full-color recording, and thermal recording printers have been developed as various terminal devices.

A thermal recording apparatus using a conventional end face type thermal head will be described below.

FIG. 1 is a side view of an essential part showing a conventional thermal recording apparatus.
Is a rotating roller, 2a is an image receiving paper, 2b is a transfer paper, and 3 is an end face type thermal head. The rotary roller 1 is rotationally driven in the direction of the arrow by a rotary drive means (not shown), and the image receiving paper 2
The transfer paper 2b and the transfer paper 2b are configured to be conveyed in the directions of the arrows. A color material layer is provided on the surface of the transfer paper 2b on the image receiving paper side. As shown in FIG. 2, the end surface type thermal head 3 is provided with a plate-shaped heating element substrate 3b having a plurality of heating elements 3a with its end surface curved, and is rotated via an image receiving paper 2a and a transfer paper 2b. The roller 1 is held by an appropriate mechanism (not shown) capable of pressure contact and separation so as to be pressed in the direction of the arrow. The pressed state is shown in FIG. Center of rotating roller 1 and apex P of end face
Main plane 3c of heating element substrate 3b that passes through the line connecting to and the apex of the end face
The end surface type thermal head 3 is arranged so that the line parallel to the line is aligned with the line.

Next, the recording operation will be described. The end surface type thermal head 3 is moved in the direction of the arrow through the image receiving paper 2a and the transfer paper 2b to press it against the rotating roller 1, and the rotating roller 1 is rotated in the direction of the arrow to receive the image receiving paper 2a. While the transfer paper 2b is fed in the direction of the arrow, the color material layer (not shown) on the transfer paper 2b is melted (or sublimated) by selectively heating the heating element 3a according to the image signal and transferred to the image receiving paper 2a. Can be recorded. In the conventional thermal recording apparatus as described above, the line connecting the apex P of the end surface type thermal head 3 and the center of the rotating roller 1 and the line parallel to the main plane 3c passing through the apex are arranged in a straight line. Therefore, it is difficult to make this condition over the entire width of the heating element array direction, and if the apexes P of the end faces at both ends in the heating element array direction are displaced in the front-back direction of the transfer paper 2b and the image receiving paper 2a, Since the end surface is a curved surface, the pressing force becomes stronger on the side displaced to the front side, and the pressing force becomes smaller on the side displaced rearward, resulting in a difference in the pressing force, resulting in a recording density difference in the heating element array direction. However, there is a problem in that the print quality deteriorates.

Further, in the end surface type thermal head, the heating element forming surface also has a curvature, and particularly when the rotating roller abutting through the recording medium also has a curvature, the recording paper running direction at the apex of the curvature surface Before and after, the difference in pressing force becomes large, and the difference in density also appears remarkably.

In addition, since there is a difference in the pressing force in the heating element arrangement direction, the image receiving paper 2
Also, the transfer force of the transfer paper 2b is different in the heating element arrangement direction. That is, on the side deviated to the front side in the conveying direction of the image receiving paper 2a and the transfer paper 2b, the rotary roller and the end surface type thermal head are brought into pressure contact with each other, and when the rotary roller rotates, it becomes a biting side and a force larger than a predetermined pressing force is applied. It acts on the image receiving paper 2a and the transfer paper 2b. In particular, since the transfer paper is very thin with 3 to 10 μm in order to improve the thermal efficiency of the color material layer, it is susceptible to the influence and cannot be stably conveyed, and the print quality is deteriorated.
In a remarkable case, wrinkles were generated and an unrecordable state was also generated.

An object of the present invention is to solve the above problems by providing an angle between a line connecting the center of the rotating roller and the apexes of the end faces and a line passing through the apexes of the end faces and parallel to the main plane of the heating element substrate. An object of the present invention is to provide a heat-sensitive recording apparatus which is configured so as to reduce pressure unevenness in the heating element array direction and to stably perform recording with high print quality.

According to the present invention, a plurality of heating elements are formed in a row on an end surface having a curvature, and individual electrodes from the heating element on the end surface to one main plane and from the heating element on the end surface to the other main plane. An end surface type thermal head having a plate-shaped heating element substrate each having a common electrode formed thereon, and a rotary roller which is relatively pressed against and separated from the recording medium and rotates at least in the recording paper running direction during recording. The end surface type thermal head and the rotating roller are pressed against each other with a force substantially parallel to the main plane of the end surface type thermal head, and the line connecting the apex of the end surface of the end surface type thermal head and the center of the rotating roller and the apex of the end surface are provided. The angle θ formed by the line parallel to the main plane of the heating element substrate passing through is 180 °> θ on the front side in the recording paper running direction, so there is little unevenness in the pressing force in the heating element array direction and stable and high quality. Of printing It is kill things.

Description of Embodiments FIG. 3 is a side view of essential parts of a thermal recording apparatus showing a first embodiment of the present invention. 4 is a rotating roller, 5 is a recording medium, and 6 is an end face type thermal head. The rotating roller 4 is formed by lining a silicone rubber or the like on the outer periphery to give an elastic force, and is rotated in the arrow direction by a rotation driving means (not shown) to convey the recording medium 5 in the arrow direction. Recording medium 5
Is composed of the image receiving paper 5a and the transfer paper 5b, and the image receiving paper 5a of the transfer paper 5b
A color material layer (not shown) is applied to the side surface. The color material layer (not shown) is made of a fusible material or a sublimable material, and is transferred to the image receiving paper 5a by applying heat with the end surface type thermal head 6. The end surface type thermal head 6 includes a heating element substrate 6a, a base 6b, a wiring P plate 6c and a heating element driving semiconductor element.
6d, a protective cover 6e, a mounting bracket 6f for mounting the heating element substrate 6a to the base 6b at both ends, and a connector 6g for electrically connecting to an electric system of the apparatus body (not shown). The heating element substrate 6a is an end surface of the ceramic substrate 7 as shown in FIG.
7a and a glass glaze layer 7c on the main plane 7b, the individual electrodes 7g from the main plane 7b to one end of the heat generating body 7d the heating element 7d on the end face glaze, and from the main plane 7e to one end of the heating element 7d. Each common electrode 7f is formed. The curvature of the glaze surface of the end face 7a is 1 when the thickness t of the ceramic substrate 7 is 1.
The thickness is made as thin as ~ 4 mm, and the glass is applied by utilizing the surface tension of the glass when firing the glass glaze layer 7c, and the surface of the end face is curved. By making the end face forming the heating element 7d a curved surface, the contact with the recording medium 5 is improved and the heat of the heating element 7d is easily transferred to the recording medium 5. The heating element substrate 6a configured as described above is attached and fixed to the base 6b at both ends thereof by the attachment fittings 6f. The wiring P board 6c is adhesively fixed to the base 6b with a double-sided tape or the like. The heating element driving semiconductor element 6d has one end for the individual electrode 7g of the heating element substrate 6a and the other end for the wiring P plate.
Each of them is electrically connected to a wiring pattern (not shown) on 6c. The protective cover 6e is the semiconductor element 6 for driving the heating element.
d and double-sided tape or the like are adhesively fixed on the heating element substrate 6a and the wiring P board 6c so as to protect the connecting portions at both ends. The connector 6g is configured to be connected to a wiring pattern (not shown) of the wiring P plate 6c and to be connected to an electric system of the apparatus main body (not shown). As shown in FIG. 5, the arrangement of the rotating roller 4, the recording medium 5 and the end surface type thermal head 6 passes through the line connecting the center x'of the rotating roller 4 and the apex P'of the end surface and the apex P'of the end surface. The angle θ formed by the lines parallel to the planes 7b and 7e on the front side with respect to the conveying direction of the recording medium 5
Is 180 °> θ. That is, even if the heating element array direction of the end surface type thermal head 6 is deviated in the conveying direction of the recording medium 5, when the end surface type thermal head 6 is pressed in the arrow direction and the rotary roller 4 is rotated in the arrow direction, The entire heating element on the curved surface including the apex P'of the mold thermal head 6 is formed as the escape side. Therefore, there is no need to divide into the escape side and the bite side as in the conventional case. Generally, the recording density increases as the pressing force increases up to a predetermined pressing force, but the recording density becomes almost constant when the pressing force is a predetermined value or more. Therefore, the rotary roller 4 and the end surface type thermal head 6 are brought into pressure contact with each other,
When the rotary roller 4 rotates in the direction of the arrow, since the end surface type thermal head 6 is formed on the escape side over the entire width in the heating element array direction with respect to the rotary roller 4, by applying a pressing force of a predetermined value or more, It is possible to reduce the density difference before and after the recording type thermal head 6 in the traveling direction of the recording medium 5.

Next, the recording operation will be described. The end surface type thermal head 6 is moved in the direction of the arrow through the recording medium 5 (image receiving paper 5a, transfer paper 5b) to the rotating roller 4, and the pressing force is applied to the rotating roller 4 in a direction substantially parallel to the main planes 7b and 7e. Press to apply. At the same time, the rotating roller 4 is rotated in the direction of the arrow, and while the recording medium 5 is conveyed in the direction of the arrow, the heating element 7d is selectively heated according to the image signal to transfer the color material layer of the transfer paper 5b to the image receiving paper 5a. Thermal transfer recording can be performed on the image receiving paper 5a. The pressing force is set to a pressing force that can sufficiently obtain the recording density as described in the above configuration. Further, since the end surface type thermal head 6 is arranged on the escape side with respect to the rotating roller 4 when the rotating roller rotates, the force larger than the pressing force does not act on the recording medium 5. Therefore, the recording paper can be stably conveyed, and unlike the conventional case, it is not divided into the bite side and the flank side in the heating element array direction, but the flank side is provided over the entire width, so that a stable pressing force is obtained. Therefore, it is possible to minimize the occurrence of uneven recording density due to the difference in pressing force. When the predetermined recording is completed, the end surface type thermal head 6 is separated from the rotating roller 4,
The recording medium 5 is carried out by an appropriate conveying means (not shown), and the recording operation is completed.

As described above, the center x'of the rotating roller 4 and the apex P'of the end surface
The angle θ formed by the line connecting the lines and the line parallel to the main plane that passes through the vertex of the end face is defined as the angle θ on the front side with respect to the running direction of the recording medium 5.
With 180 °> θ, press the end surface type thermal head 6 in pressure contact,
When the rotating roller 4 is rotated, the end surface type thermal head 6
The recording medium 5 can be stably conveyed by arranging the heating element on the escape side over the entire width of the heating element array direction, and the unevenness of the pressing force in the heating element array direction can be reduced to stably obtain high-quality printing. be able to.

FIG. 6 is an enlarged side view of an essential part of a thermal recording apparatus showing a second embodiment of the present invention. The difference from the first embodiment is that the apex P ′ of the end surface of the end surface type thermal head 6 and the heating element are different. The heating element is formed by shifting the center Q, and the heating element center Q is arranged in front of the apex P'of the end face in the traveling direction of the recording medium 5, and the rotary roller 4 is arranged in the direction of the arrow. When rotated, the pressing force can be more effectively applied to the heating element portion than in the first embodiment, and the pressing force can be reduced.

In the embodiment of the present invention, the recording medium is composed of the image receiving paper and the transfer paper, but a direct color type thermosensitive recording paper may be used.

Further, although the rotation roller is configured to be rotationally driven to convey the recording medium, a recording medium feed roller may be separately provided and the rotation roller may be driven according to the conveyance of the recording medium.

Further, in the embodiment of the present invention, the end surface type thermal head is moved and pressed against the rotating roller via the recording medium,
It goes without saying that the rotating roller may be moved.

EFFECTS OF THE INVENTION The heat-sensitive recording apparatus of the present invention is formed by forming a plurality of heating elements in a row on the end surface having a curvature, and forming individual electrodes and common electrodes extending from the heating element on the end surface to two main planes. An end face type thermal head equipped with a heating element substrate,
An end surface type thermal head and a rotating roller which are pressed against each other and separated from each other via a recording medium and rotate at least in the recording paper running direction at the time of recording, and the end surface type thermal head and the rotating roller are the main planes of the end surface type thermal head. The angle θ between the line that connects the center of the rotating roller and the apex of the end face of the end surface type thermal head and the line that passes through the apex of the end face and is parallel to the main plane is pressed in the recording medium running direction while being pressed by substantially parallel forces. By setting 180 °> θ on the front side of, the end surface type thermal head is configured to be on the escape side when the rotating roller is rotated, and the influence of uneven pressing force in the heating element arrangement direction is reduced, High-quality printing can be stably obtained by reducing the recording density difference, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a side view showing an essential part of a conventional thermal recording apparatus, and FIG.
FIG. 3 is an enlarged side view of essential parts showing a pressed state of a rotary roller, an end surface type thermal head and a recording medium, and FIG.
4 is an enlarged perspective view showing the shape of the heating element substrate, and FIG. 5 is an enlarged main portion showing the pressure contact state of the rotating roller with the recording medium and the end surface type thermal head. A side view and FIG. 6 are enlarged side views of essential parts showing a pressed state of the rotary roller of the thermal recording apparatus and the end surface type thermal head and the recording medium in the second embodiment of the present invention. 1,4 ...... Rotary rollers, 2a, 5a …… Image receiving paper, 2b, 5b …… Transfer paper, 5 …… Recording medium, 3,6 …… End face type thermal head, 3
a, 7d …… Heating element, 7g …… Individual electrode, 7f …… Common electrode, P,
P '... apex of end face, Q ... center of heating element, x, x' ... center of rotating roller

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Noboru Miyaji 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-57-103863 (JP, A) JP-A-57-93171 (JP, A) Actually developed 56-95846 (JP, U)

Claims (2)

[Claims] 1. A plurality of heating elements are formed in a row on an end surface having a curvature, and individual electrodes extending from the heating element on the end surface to one main plane and an individual electrode extending from the heating element on the end surface to the other main plane. An end surface type thermal head having a plate-shaped heating element substrate formed by forming a common electrode, respectively, and the end surface type thermal head and the end surface type thermal head are pressed and separated relative to each other via a recording medium, and at least in the recording paper running direction at the time of recording. A rotary roller that rotates, presses the end surface thermal head and the rotary roller with a force substantially parallel to the main plane of the end surface thermal head, and the center of the rotary roller and the end surface thermal head An angle θ formed by a line connecting the apex of the end face and a line parallel to the main plane of the heating element substrate passing through the apex of the end face of the end face type thermal head is 180 ° on the front side with respect to the recording paper running direction> θ and A thermal recording device characterized by the above. 2. An end surface type thermal head, wherein the center of the heating element of the end surface having a curvature is displaced from the apex of the end surface so that the center of the heating element is located closer to the front side of the apex of the end surface in the recording medium running direction. The thermal recording apparatus according to claim 1, further comprising a thermal head.