JPH01308664A - Thermal recorder - Google Patents

Abstract

PURPOSE:To obtain a thermal recorder having a small size at a low cost with a simple mechanism by so recording that a guide roller is disposed slightly at a lower level from the top of a thermal recording unit to operate a pressure contact force component to the unit with respect to the transfer force of a heat sensitive recording sheet transfer direction. CONSTITUTION:When a motor 8 is driven to rotate a feed roller 7 clockwise, a heat sensitive recording sheet 4 is fed by the roller 7. In this case, a resistance is applied to the rotation of a heat sensitive recording sheet roll 4R by the elasticity of a leaf spring 17, and a tension is strongly applied to the sheet. A route bent at its end as a top by guide rollers 5, 6 disposed slightly at a lower level than the position level of a heat generation recorder 1H of an end face type thermal head 1 is formed on the sheet 4. The sheet 4 conveyed by a tension P is strongly brought into pressure contact with the recorder 1H by a branch force component P' of a bending angle. Since the length l of the end flat part of the recorder 1H is extremely short, the force component P' is concentrically applied to the part, thereby effectively providing its close contact.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a thermal recording device using an end-face type thermal head having a heat-generating recording section on the end surface of a substrate, and particularly to a heat-sensitive recording device that uses an edge-type thermal head having a heat-generating recording section on the end surface of a substrate. Related.

(Prior art) The shape of the thermal head of a thermal recording device that performs thermal recording on thermal recording paper is such that a large number of heating resistors are arranged side by side as a recording section on the plane of a substrate, and the necessary It has a structure in which electrodes, driving ICs, etc. are arranged, and a cover is provided to protect them.

A thermal recording device using such a conventionally shaped thermal head has the following problems.

(Problems to be Solved by the Invention) FIG. 5 shows the mechanical arrangement of the thermal head 1 and the platen roller 2. As shown in FIG. Platen roller 2 and thermal head 1
In order to properly press against the heat-generating recording section IH of the platen roller 2, it is necessary to increase the diameter of the platen roller 2, but this is limited by the position and shape of the cover 3. If the platen roller becomes large, the thermal head must also be made large in order for it to work effectively, and on the other hand, it is not a good idea in terms of space and cost.

Furthermore, when transporting the thermal recording paper 4 to the thermal radar 1, the transport path must be designed to avoid the above-mentioned cover 3. cannot fit within a limited space unless a complicatedly curved conveyance path is created using guide rollers or the like.

Therefore, in order to maintain good image quality, it is important to be able to convey the thermal recording paper while contacting the heat-generating recording section of the thermal head with appropriate pressure.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned conventional problems and to provide a small, low-cost thermal recording device with a simple mechanism.

(Structure and operation) In order to achieve the above object, the present invention provides a certain bank tension when the thermal recording paper is conveyed by a feed roller, and the thermal recording paper passes over the heat-generating recording portion of the end wall thermal head. At this time, the guide rollers disposed before and after the edge-type thermal head in the thermal paper conveyance direction apply pressure component force to the heat-generating recording section with respect to the conveyance force in the thermal recording paper conveyance direction. It is characterized by being arranged at a slightly lower level than the apex of the heat generation recording section.

According to the present invention, when the thermal recording paper is pulled by the feed roller, the thermal recording paper is conveyed while being pressed against the foot roller by the pressure member. Then, resistance is added to the roll rotation so that back tension against the tensile force of the feed roller acts on the heat-sensitive recording paper roll, and a strong tension is applied to the roll. Furthermore, in the heat-generating recording section of the thermal head, a pressing force is applied to one heat-generating recording section by guide rollers disposed at the front and rear in the conveying direction, with the heat-sensitive recording paper at its apex.

For this reason, the conveyance path of the thermal recording paper is simple and compact, and as it is conveyed, it is brought into contact with extreme pressure at the 1 heat-generating recording section, and images can be recorded accurately and image quality can be improved. can.

(Embodiment) FIG. 1 shows a layout diagram of constituent members according to an embodiment of the present invention. In the figure, 1 is an end wall thermal head, IH is a heat-generating recording section constituted by a heat-generating resistor, and 4 is a heat-sensitive recording paper wound around a heat-sensitive recording roll 4R. 5 and 6 are guide rollers for the thermal recording paper 4;
The heat-sensitive recording paper 4 is provided at a position where it is guided at a level slightly lower than the apex of the heat-generating recording section IH. Reference numeral 7 denotes a feed roller, to which the rotational power of a motor 8 is transmitted via a belt 9 to convey the thermal recording paper in the direction of the arrow. 10 is a pressure roller that presses the thermal recording paper 4 against the feed roller 7 by the elasticity of a spring 11; this pressure roller 10 is connected to the shaft 1;
It is supported by a lever 13 whose rotation axis is z. 14
This is a case for accommodating the above-mentioned heat-sensitive recording roll 4R and motor 8.

FIG. 2 shows a case where a pressure plate 15 is used as another example of the pressure roller 10 shown in FIG.
The thermal recording paper 4 is pressed against the side with appropriate pressure.

These pressure rollers10. pressure plate 1
5 applies a constant tension to the conveyance direction when the thermal recording paper 4 is conveyed.

FIG. 3 is a sectional view showing the structure of the solid case 14 (thermal recording paper roll 4R portion) shown in FIG. As shown in the figure, a thermal recording paper roll 4R is rotatably supported by thermal recording paper roll holders 16 disposed on the left and right walls 14W. and either wall surface 14 of the case 14
A plate spring 17 is disposed between v (on the right side when rotated) and the axis of the roll holder 16, which biases the plate spring 17 in the axial direction. , back tension is added.

The operation of the embodiment configured as described above will be explained with reference to the above-mentioned drawings and FIG. 4, which is a partial view of the end face type thermal head 1.

When the motor 8 is driven and the feed roller 7 is rotated clockwise via the belt 9, the thermal recording paper 4 is sent out by the conveying force due to the large friction of the feed roller rough. At this time, the rotation of the thermal recording paper roll 4R is resisted by the elastic action of the leaf spring 17. However, since the conveyance force by the feed roller rough is stronger than the temporary spring 17, the thermal recording paper 4 is sent out in the direction of the arrow.

That is.

At this time, back tension acts on the heat-sensitive recording paper, which causes a strong tension to be applied to it.

The path when the thermal recording paper 4 given tension in this way is guided linearly by the guide rollers 5 and 6 is as follows:
A path curved by a guide roller located at a slightly lower level than the position level of the heat-generating recording section IH at the tip of the edge-type thermal head 1, which is disposed approximately at the center of the guide rollers 5 and 6, with the tip as the apex. is formed as shown in FIG.

Therefore, the thermal recording paper 4, which is conveyed with a large tension P in the pulling direction, is strongly pressed against the heat-generating recording portion IH of the edge type thermal head 1 by a component force P' caused by the refraction angle.

Since the length Q of the flat end surface portion of the heat-generating recording portion IH is extremely small, the component force P' is concentratedly applied to this portion, thereby making the 'ijE adhesion more reliable.

In addition, this edge-type thermal head has electrodes, driving ICs, etc. arranged on the substrate like a general flat-type thermal head, but since the heat-generating recording section is provided on the edge of the substrate, Even if a cover is required for this purpose, it does not affect the conveyance of the thermal recording paper at all, as described above.

Although this example deals with the case of thermal recording paper,
It is clear that the present invention can also be implemented with other printing devices that perform similar recording.

(Effects of the Invention) As explained above, the present invention effectively utilizes the tension applied to the thermal recording paper and its component force to press the thermal recording paper against the heat-generating recording portion of the edge-type thermal head. ,
Unlike conventional devices, this method does not use a platen roller or special mechanisms or members, and has the advantage of being easily realized at low cost.

[Brief explanation of the drawing]

FIG. 1 is a layout diagram of component parts according to an embodiment of the present invention, FIG. 2 is a mechanism diagram using a pressure plate 15 as another example of the pressure roller 10 shown in FIG. 1, and FIG.
4 is a cross-sectional view showing the structure of the case 14 shown in FIG.
FIG. 5 shows a mechanical layout diagram of a conventional thermal head 1 and platen roller 2. As shown in FIG. 1... Edge type thermal head, IH... Heat generating recording section, 4... Thermal recording paper, 4R... Thermal recording roll, 5, 6... Guide roller, 7...
Feed roller, 8...Motor, 9...Belt, 10...Pressure roller, 11...Spring, 12...Shaft, 13...Lever, 14...Case, 14w... Wall surface, 15... Pressure plate, 16... Thermal recording paper roll holder, 17...
leaf spring. Patent applicant Ricoh Co., Ltd. 1 Figure 2 Figure 3 Figure 14 Case Figure 4 P'≧ゝゝP Figure 5

Claims (1)

[Claims] When the thermal recording paper is conveyed by the feed roller, a certain back tension is applied, and when the thermal recording paper passes over the heat-generating recording section of the edge-type thermal head, the thermal recording paper is conveyed in front of the edge-type thermal head in the conveying direction. The guide roller is disposed at a level slightly below the apex of the heat-generating recording section so that the guide roller disposed later applies a pressing force to the heat-generating recording section with respect to the conveyance force in the direction of conveyance of the thermal recording paper. A thermal recording device featuring: