JPS60105551A - Fixing device for thermal recoring head - Google Patents

Abstract

PURPOSE:To prevent unevenness of printing by supporting an intermediate portion between paired springs on the counter-platen pressing face of the other side end portion in the direction of right angle to the axial direction of the platen of a thermal recording head. CONSTITUTION:An universal joint 20 is fixed to a spherical rotator 18 fixed to the bottom of a thermal recording head 4 and a supporter 23 and is made up of a supporter 19 embracing the spherical rotator 18. Since the head 4 is supported rotatably in any direction by the universal joint 20, the contact state between the head 4 and the plate 3 can be always kept uniform. The pressing force in the longitudinal direction of the head 4 and the platen 3 can particularly be equalized to prevent the unevenness of printing.

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Summary of the Invention> The present invention is a book relating to a mounting device for a thermal recording head in a recording device such as a thermal recording device or a printer.

<Prior art> Among thermal recording systems, for example, in a thermal transfer recording device, an ink sheet consisting of a plastic film such as polyester coated with a heat-melting solid ink is overlaid on a recording paper, and a thermal head is attached to a platen. While in pressure contact with the solid ink, a thermal pulse is applied from a thermal head to melt the solid ink and transfer it to recording paper to record the necessary information.

1 and 2 show a conventional recording apparatus disclosed in, for example, Japanese Unexamined Patent Publication No. 58-16866. A platen 3 rotatably supported by shafts 1 and 2 at both ends of a support member (not shown) is pressed against a flat thermal recording head 4. As shown in FIG. One ends of a pair of #i tension springs 5 and 6 are fixedly attached to left and right positions of one end of the thermal recording head 4 in a direction perpendicular to the 3-axis direction of the platen. This tension spring5.
The other end of 6 is latched to a support member 9.11 via an adjustment mechanism 1, 8 that adjusts its tension. A pair of bent pieces 4A and 4B provided at the ends of the thermal recording head 4 in the 3-axis direction of the platen are pivotally connected to a support member (not shown) by shafts 12 and 13.

The recording paper 14 and the ink sheet 15, which are conveyed in a stacked manner, are brought into pressure contact between the thermal recording head 4 and the platen 3, and are subjected to heat pulses applied from the thermal recording head 4 to the ink sheet 15. The ink melts accordingly,
The image is transferred onto recording paper 14 and recorded.

In such a conventional thermal head support device, the platen 3
The axis 1.2 of the thermal recording head 4 and the axis 12.13 of the thermal recording head 4 are arranged parallel to each other.
The pressure contact action is provided by the tension of a tension spring 5.6 acting on each end of the platen of the thermal recording head 4 in the axial direction, and the tension is adjusted by adjusting the adjustment mechanism 1.8. . However, in reality, even if sufficient tension adjustment is performed, there is an error in the parallelism between the axis 1.2 of the platen 3 and the axis 12.13 of the thermal recording head 4, and the tension spring 5.6
Due to the deflection of the thermal recording head 4 due to the difference in the elasticity of the thermal recording head 4, the pressure contact between the thermal recording head 4 and the platen 3 becomes uneven in the 3-axis direction of the platen, that is, in the long-term direction. There was a problem in that the density was uneven.

<Summary of the Invention> The present invention has been made in view of the conventional circumstances as described above. It is an object of the present invention to provide a heat-sensitive recording head mounting device that can easily eliminate non-uniform pressure contact with a platen disposed opposite to the heat-sensitive recording head.

<Embodiment of the Invention> An embodiment of the present invention will be described below with reference to FIGS. 3 and 4.

In these figures, the same elements as in FIGS. 1 and 2 are given the same reference numerals to simplify the explanation.

That is, in the figure, 16 and 17 are a pair of compression springs for pressing the thermal recording head 4 against the platen 3, and are provided between one end of the head 4 in a direction perpendicular to the axial direction of the platen 3 and the support portion 23. , are interposed spaced apart in the three axial directions of the platen. A pair of compression springs 16 on the bottom surface of the other end of the 20#i thermal recording head 4 in the direction perpendicular to the 3-axis direction of the platen;
A universal joint supports an intermediate portion corresponding to between 17 and a spherical rotating part 18 fixed to the bottom surface of the thermal recording head 4, and a supporting part 19 fixed to the supporting part 23 and containing the spherical rotating part 18. It consists of and. A pair of stoppers 21 and 22 are in contact with the end surfaces of the thermal recording head 4 in the 3-axis direction of the platen, respectively, to restrict lateral wobbling of the head 4.

According to this configuration, since the thermal recording head 4 is supported by the universal joint 20 so as to be freely rotatable in any direction, the pressure contact state between the head 4 and the platen 3 can always be made uniform. In particular, head 4
This makes it possible to equalize the pressing force in the longitudinal direction between the platen 3 and the platen 3, thereby preventing uneven printing.

In the above embodiment, an example was described in which the present invention was applied to a transfer type recording device using an ink sheet, but it is of course applicable to any type of recording device using a thermal recording head.

<Effects of the Invention> As described above, according to the present invention, the thermal recording head is supported by a universal joint that can rotate in any direction,
Since the head and the platen are pressed against each other by springs installed at two locations spaced apart in the axial direction of the thermal recording head in the direction perpendicular to the axial direction of the platen, the longitudinal direction of the thermal recording head and the platen is The pressing force in the direction can be made uniform, which is highly effective in preventing uneven printing.

[Brief explanation of the drawing]

Fig. 1 is a front view of a conventional thermal head mounting device, Fig. 2 is a side view of the same device, Fig. 3 is a front view of a thermal recording head mounting device showing an embodiment of the present invention, and Fig. 4 is the same as above. FIG. 3 is a side view of the device. 3...Platen 4...Thermal recording head 16.17
...Compression spring 18...Rotating part 19...Support part 20...Universal joint agent Masuo Oiwa (and 2 others) Fig. 1 Fig. 3 Fig. 4

Claims (1)

[Claims] It is equipped with a thermal recording head, a platen placed opposite to the head and for pressing recording paper against the thermal recording head, and performs thermal recording on the recording paper in response to heat pulses from the thermal recording head. In the recording apparatus, a pair of springs for pressing the thermal recording head against the platen are provided at one end of the thermal recording head in a direction perpendicular to the platen axis direction, spaced apart in the platen axis direction;
A substantially intermediate portion of the opposite end of the thermal recording head in the direction perpendicular to the platen axis direction, corresponding to between the pair of springs, is connected to a spherical rotating portion and a support portion for the rotating portion. A mounting device for a thermal recording head, characterized in that it is supported by a unilateral joint consisting of .