JPH01136779A - Printer - Google Patents

Abstract

PURPOSE:To prevent a transfer sheet from being deformed concurrently with the feeding thereof and obtain printing characteristics for high image quality, by such a control that the timing of pressing and driving a printing head does not overlap with the timing of feeding the transfer sheet. CONSTITUTION:Application of a pressing force to a thermal head 4 is conducted only at the time of printing on a paper 15 by the head 4 through a transfer sheet 6 therebetween, the pressing force can be eliminated at the time of feeding the transfer sheet 6 and the paper 15, and the application and elimination of the pressing force can be alternately performed. Thus, frictional forces are not generated between the head 4, the transfer sheet 6 and the paper 15 during the feeding, and printing and the feeding are alternately conducted for each line, so that the sheet 6 can be separated from the paper 15 before a transferred ink is hardened on the paper 15. Therefore, the sheet 6 is prevented from being elastically or plastically deformed concurrently with these operations, and printing characteristics for high image quality can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a printing device, and more particularly to a transfer type printing device.

2. Description of the Related Art A conventional printing device has a print head 3 as shown in FIG.
A paper 34 is inserted between the print head 32 and the platen 31, and a tape-shaped transfer sheet 33 having a width narrower than the paper 34 is inserted between the print head 32 and the paper 34 in the moving direction P of the paper 34. It is configured to be transferred in the orthogonal direction Q.

Then, by pressing the print head 32 toward the platen 31 using a pressing means (not shown) in a manner corresponding to the image to be printed, the ink on the transfer sheet 33 is transferred to the paper 31.
After transferring and printing.

The paper 34 and the transfer sheet 33 are moved by a predetermined amount.

Problems to be Solved by the Invention However, in the above configuration, the paper 34 and the transfer sheet 33 are always moved while a pressing force is applied to the print head 32, so the transfer sheet 33 has no ink to be transferred to the paper 34. It is pressed against this paper 34 in a hardened state, causing in-plane deformation in the moving direction P of the paper 34 as shown in FIG.
As a result of not being able to position the transfer sheet 33 at a predetermined position relative to the print head 32, there is a problem that image quality defects such as inability to transfer or ink smearing occur.

Further, there is also a problem in feeding the transfer sheet 33 in the moving direction Q, in that pulling the transfer sheet 33 causes deformation, and in severe cases, the transfer sheet 33 may break.

SUMMARY OF THE INVENTION The present invention overcomes the above-mentioned conventional problems and aims to provide a printing device that is free from deformation due to transfer of a transfer sheet and that provides high-quality printing characteristics.

Means for Solving the Problems In order to achieve the above object, the present invention provides timing for pressing and driving the print head.

The present invention is characterized in that it includes a control device that controls the timing so as not to overlap with the timing of transferring the transfer sheet.

Function The present invention has the above-mentioned configuration, and the pressure force on the print head is applied only when the print head prints on the paper via the transfer sheet, and can be removed when the transfer sheet and paper are transferred. , and this can be done alternately. In other words, since the transfer sheet and paper are transferred when the pressure force on the print head is released, the print head does not press the transfer sheet and paper during transfer.
In addition, since printing and transport are performed alternately for each line, the pressure on the transfer sheet is released and the transfer sheet is separated from the paper while the ink transferred to the paper is not cured. Can be done.

In this way, it is possible to avoid the pressure force and the adhesion force caused by the hardening of the ink on the paper, thereby eliminating the deformation of the transfer sheet due to transportation, and it is possible to obtain high-quality printing characteristics.

EXAMPLE Hereinafter, a first example of the present invention will be described with reference to FIGS. 1 to 4. In Figure 1, 1 is the frame of the printing device;
A pair of mounting platens located on both sides of its bottom wall)2
A platen 3 consisting of a pair of upper and lower feed rollers at a and 2b
and a support roller 16 are rotatably supported. or,
A thermal head 4 is disposed above the support roller 16.

This thermal head 4 is always urged in a direction to press the support roller by an urging means (not shown). A bracket 14 is placed on the thermal head 4, and the thermal head 4 is attached via the bracket 14.
A solenoid 13 is provided to move the motor upward. The thermal head 4 has a heating section on its end side surface.

A transfer sheet cassette 6 containing a narrow tape-shaped transfer sheet 6 that can be drawn out and wound up is disposed above the thermal head 4, and the drawn-out transfer sheet e is transferred to the support roller 16 and the thermal head 4. passed between. This transfer sheet cassette 6 is mounted on a platen) 2a,
Both ends are supported by support brackets 7a and 7b arranged adjacent to each support platen) 7a.
.

7b is provided with a reel shaft 8 that rotatably supports a reel 1v (not shown) around which the transfer sheet 6 of the transfer sheet cassette 5 is wound, and a guide roller 9 that guides the drawn-out transfer sheet 6. ing. Further, as shown in FIG. 2, the transfer sheet cassette 6 has a maximum printing width of W.
, when the effective width of the transfer sheet 6 is W, sin θ=w/
It is arranged to be inclined by an angle θ given by W with respect to the axes of the thermal head 4 and the support roller 1θ. A motor 1o for rotationally driving the platen 3 is attached to the mounting platen 2b, and is configured to transmit rotational force via a timing belt 11.

The support bracket 7 also includes a reel drive device 12 that rotationally drives the reel shaft 8 of the transfer sheet cutter 5.
is provided.

Further, as shown in FIG. 3, a solenoid driver 21 operates the solenoid 13 to float the FB thermal head 4 when turned on. 22 is a driver for a thermal head,
When turned on, the heating section of the thermal head 4 is activated. 23
1 is a transfer sheet transport driver which, when turned on, operates the reel drive device 12 to transport the transfer sheet 6. 2
Reference numeral 4 denotes a platen driver which, when turned on, operates the motor 1o to transport the paper 16. 25 to 28 are power supplies for these drivers 21.22, 23.24, and 29
is a generator that controls each driver 21.22, 23.24.

The operation of the printing apparatus configured as described above will be explained based on the time chart shown in FIG.

Paper 16 and transfer sheet 8 are transferred to thermal head 4 and support roller 1.
Pass between 6 and 6. At this time, the solenoid driver 21 is ON and the thermal head 4 is floating.

First, the solenoid 13 is turned OFF and the urging means is used to turn off the solenoid driver 21, and while the thermal head 4 is pressed by the urging means, the thermal head driver 22 is turned ON to operate the thermal head 4. At this time,
The transfer sheet transport driver 23 and the platen driver 24 are OFF. As a result, by locally heating a predetermined portion of the transfer sheet 6 corresponding to the image to be printed, one dot (one line) is printed in the transport direction of the paper 15.
can be printed.

When printing for one dot is completed, the solenoid driver 21 is turned on, the solenoid 13 is activated, and the thermal head 4 is lifted up and unloaded, and at the same time, the platen driver 24 is turned on to print one dot of the paper 16. At the same time, the transfer sheet transport driver 23 is also turned on to transport the transfer sheet 6 in a direction intersecting the transport direction of the paper 16, making it possible to print the next one dot.

By repeating the above operations, desired printing can be performed on the entire surface of the paper 15.

In this way, the pressure on the thermal head 4 is applied only when the print head 4 prints on the paper 16 via the transfer sheet 6, and can be removed when the transfer sheet 6 and paper 15 are transferred. This can be done alternately, so the heat-sensitive head 4. Since no frictional force is generated between the transfer sheet 6 and the paper 15, and printing and transport are performed alternately for each line, the transfer sheet 6 is transferred to the paper 15 before the transferred ink hardens on the paper 16. Since the transfer sheet 6 can be separated from the transfer sheet 6, the elastic-plastic deformation of the transfer sheet 6 caused by these is eliminated, and printing characteristics of commercial quality can be obtained.

A second embodiment of the invention is shown in FIGS. 5 and 6.

In this embodiment, the support roller 16 of the first embodiment is omitted,
The platen 43 serves both to support the pressure from the thermal head 44 and to feed the paper 16. Also, this platen 43
Unlike the first embodiment, the platen driver 23 that operates the platen is turned ON when the thermal head driver 22 is ON and the solenoid driver 21 is OFF. The rest of the structure of this embodiment is substantially the same as that of the first embodiment, so it is shown with the same reference numerals in FIG. 6, and the explanation thereof will be omitted.

The operation of the printing apparatus configured in this manner will be described below. The paper 16 and the transfer sheets F, 6 are placed between the thermal head 44 and the platen 43, and the urging means (
By operating the thermal head 44 while pressing the thermal head 44 with a press (not shown), and locally heating a predetermined portion of the transfer sheet 6 corresponding to the image to be printed, It is possible to print dots (one line).

At this time, as shown in the time chart of FIG. 6, the solenoid driver 21 is OFF, and the platen driver 24 is turned ON while being pressed by the thermal head 44 to drive the platen 43, so the thermal head 44. Transfer sheet 46. Frictional force acts between the sheets 66, and the transfer sheet is bent by one dot in the direction in which the sheets 55 are transported. However, if the print resolution density is assumed to be, for example, G (one machine), one dot is 1/7, 7=0.13 mm, and such minute deformation does not pose a problem to print characteristics.

When printing for one dot is completed, the solenoid driver 21 is turned on, and the solenoid 13 is activated to lift the thermal head 44 and unload it.At the same time, the transfer sheet transport driver 23 is turned on and transfers the transfer sheet 6 to the paper. The transfer sheet 6 is transferred in a direction crossing the transfer direction of the transfer sheet 15.
deformation is corrected and the amount of deformation does not accumulate. By repeating the above operations, desired printing can be performed on the entire surface of the paper 65.

As described above, the platen 43 serves both to support the pressure from the thermal head 44 and to feed the paper 16, and the print head driver 22. By controlling the timings of the solenoid driver 21, the platen driver 24, and the transfer sheet transport driver 23 so that they do not overlap, the elastic deformation of the transfer sheet 6 can be controlled within an allowable range, resulting in high quality. Not only can printing characteristics be obtained, but the number of rollers can be reduced, simplifying the configuration and making it possible to downsize the device.

Effects of the Invention As described above, according to the present invention, by controlling the timing of pressing and driving the print head so that it does not overlap with the timing of transferring the transfer sheet, elastic-plastic deformation accompanying transfer of the transfer sheet can be reduced. However, it is possible to obtain high-quality printing characteristics, and even if elastic deformation occurs in the transfer sheet, the deformation can be corrected, which is a great effect.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing the first embodiment of the present invention, FIG. 2 is an explanatory diagram of the arrangement of the transfer sheet, FIG. 3 is a block diagram showing the control system, FIG. 4 is a control time chart, and FIG. 6 is a perspective view showing a second embodiment of the present invention, FIG. 6 is a control time chart, and FIGS. 7 and 8 are perspective views showing a schematic configuration of a conventional example. 3.43...Platen, 4.44...
Thermal head, 6...Transfer sheet, 1o...
...Motor, 12... Reel drive device, 13.
... Solenoid, 15 ... Paper, 21.
... Solenoid driver, 22 ... Thermal head driver, 23 ... Transfer sheet transfer driver, 24 ... Platen driver, 2
9.--- Generator. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
Figure 4 Figure 6

Claims (1)

[Claims] In a printing device that includes a print head arranged to cross the paper width, a transfer sheet that is transferred between the print head and the paper in a direction perpendicular to the paper transport direction, and a pressing device that presses the print head, A printing device comprising a control device that controls the timing of pressing and driving the print head so as not to overlap with the timing of transporting the transfer sheet.