JPH03244557A - Color thermal printer - Google Patents

Abstract

PURPOSE:To adjust the position of the printing area of a receiver in a simple and accurate manner by a method wherein a drum is rotated with a gripper fixed, and ink on an ink donor film is selectively transferred to the receiver by a thermal head while the receiver is moved. CONSTITUTION:An ink donor film 20 is taken up by a film roller 22 to a predetermined position thereof. A gripper 42 fixes a receiver 10 to a drum 32. In this state, while the receiver 10 is fed as the drum 32 is rotated clockwise, a thermal transfer is conducted by a thermal print head 18. The rotation of the drum 23 is controlled by a drum rotation drive part and a drum rotation angle detection means. The correct rotation control directly ensures the accurate setting of a transferred position of the receiver 10. In addition, because the receiver 10 can be fed only by rotating a feed roller 38 and the drum 32, the need for mounting a feed mechanism is eliminated, and a printer can be simplified in construction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a color thermal printer that transfers ink from a transfer type recording medium to an image receptor such as paper using a heated thermal recording head. The present invention relates to a color thermal printer that performs color transfer by repeatedly performing movement operations within a predetermined range.

[Prior art] Color thermal printers use a thermal recording head (hereinafter referred to as
An image receptor such as paper (hereinafter referred to as receiver) and a transfer type recording medium to which ink is attached (hereinafter referred to as ink donor film) are inserted and moved between the thermal print head) and the platen roller. , the images are sequentially transferred to the receiver using a heated thermal print head.

FIGS. 5 and 6 respectively show examples of a receiver conveyance movement mechanism and a recording section in a conventional color thermal printer.

FIG. 5 shows an example of a color thermal printer that employs a receiver reciprocating method. In the figure, a paper receiver 10 is sandwiched between two pinch rollers 12 and 14, pinch roller 12
and 14 rotations to reciprocate. The receiver 10 passes through a transfer section, which is a gap between the platen roller 16 and the thermal print head 18, between the pinch rollers 12 and 14.

Further, an ink donor film 20 is also inserted through the transfer portion so as to be superimposed on the receiver 10. The ink donor film 20 is moved by film rollers 22 and 24 in accordance with the movement of the receiver 10.

The thermal print head 18 selectively transfers ink from the ink donor film 20 to the receiver 10 which is sandwiched between the platen roller 16 and the platen roller 16 using heat.

Further, FIG. 6 shows a mechanism of a color thermal printer of a unidirectional rotation type in which the receiver 10 is moved in one direction, and as shown in the figure, the platen roller is configured as a platen drum 28. A gripper 30 is provided at the receiver 10 by this gripper 30.
is fixed to the outer periphery of the platen drum 28. Film rollers 22 and 2 for moving the thermal print head 18 and the ink donor film 20
4 is the same as the conventional example shown in FIG. 5 above.

Next, the printing operation of each printer shown in FIGS. 5 and 6 will be explained.

First, in the apparatus shown in FIG. 5, the receiver 10 is sent out by the pinch roller 12, passes through the transfer section between the platen roller 16, the thermal print head 18, and the other pinch roller 14. is conveyed until it is sandwiched. During this time, the thermal print head 18 is separated from the platen roller 16, and the ink donor film 20 is wound up to a predetermined position.

Next, the thermal print head 18
6 with a predetermined pressure, and thermal transfer is started.

During thermal transfer, the receiver 10 uses the pinch roller 12
Printing is performed while being conveyed and moved in the direction of arrow 100 by the rotation of the pinch roller 14 and platen roller 16 while being held by the frictional force of . At this time, the pinch roller 12,
14 and platen roller 16 are rotated in synchronism so that the receiver 10 does not slacken. Further, the ink donor film 20 is also wound onto the film roller 22 side in synchronization with the feeding speed of the receiver 10. When the transfer of one color of the ink donor film 20 is completed, the rear end side of the receiver 10 must still be held between the pinch rollers 12. Next, in order to transfer another color, an operation is performed to return the receiver 10 to a predetermined transfer start position. First, the thermal print head 18 pressed by the platen roller 16
6, and the ink donor film 20 is in a predetermined position (
The paper is wound up to the position of the desired color ink. During this time, the pinch rollers 12 and 14 rotate in reverse, and the receiver 10 is conveyed in the direction of arrow 200 and stopped at the transfer start position.

At this transfer start position, the front end side of the receiver 10 remains held between the pinch rollers 14.

The thermal transfer of one color is completed with the above series of operations, and color thermal transfer is performed by repeating this operation a number of times corresponding to the number of colors. For example, in the case of three colors (yellow, magenta, cyan), the above operation is repeated three times to perform transfer.

Next, in the operation of the conventional apparatus shown in FIG. 6, the platen drum 28 having the receiver 10 attached to its outer periphery is rotated by the gripper 30 to the transfer starting position. During this time, the thermal print head 18 is maintained apart from the platen drum 28, and the ink donor film 20 is wound up to a predetermined position where transfer should begin. After the platen drum 28 reaches the transfer start position and is stopped, the thermal print head 18 comes into contact with the receiver 10 on the platen drum 28 with a predetermined pressing force, and transfer starts. The transfer of one color is completed by the platen drum 28 rotating once in the direction of arrow 300, and the next transfer of the other color is performed by rotating the platen drum 28 once in the direction 300 from the transfer start position. be exposed. Therefore, when the number of rotations corresponds to the number of colors to be transferred, that is, three colors, color thermal transfer is completed by rotating the platen drum three times.

[Problem to be solved by the invention] However, the above conventional color thermal printer has the following problems:
It had the following issues.

In the case of the reciprocating method shown in Fig. 5, the receiver 10
is held and conveyed by the frictional force of the pinch rollers 12 and 14, that is, by the two rollers, respectively. Therefore, in order to transport and hold the receiver 10 in a constantly stretched state, it is necessary to keep the pressing force and frictional force of each of the pinch rollers 12 and 14 constant, and an adjustment mechanism for this purpose is required. Furthermore, when transferring the second and subsequent colors, accurate positioning of the receiver 10 is required to prevent color blurring, but in this conventional color thermal printer, the position detection and alignment of the receiver 1° is not possible. It was difficult.

Next, in the case of the unidirectional rotation type color thermal printer shown in FIG. 6, one (one color) transfer process is completed by one rotation of the platen drum 28. The problem of difficulty in position adjustment as shown in the figure is solved.

However, when using a large receiver 10, a platen drum 28 with a large diameter is used, and the conveyance mechanism and holding means for the receiver 10 must also be made larger. As a result, there was a problem in that the entire device became large.

OBJECT OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its purpose is to easily and accurately adjust the position of the printing area of the receiver, and to simplify the mechanism. An object of the present invention is to provide a color thermal printer that can achieve miniaturization of the device.

[Means for Solving the Problems] In order to achieve the above object, the color thermal printer according to the present invention is installed so as to be rotationally controllable, and has a receiver which is an object to be transferred inside, which can be freely drawn out and held in a laminated manner. a drum having a peripheral wall provided with an opening for sending out the receiver from the holding means onto the outer periphery; and a drum configured to rotate together with the drum and fixing the pulled-out receiver to the drum. a gripper that can be switched to fix or release the fixing; a thermal print head that is disposed near the drum and is capable of pressing a predetermined portion of the receiver sent out onto the drum's outer periphery onto the drum's outer periphery; and the thermal print head. an ink donor film having multiple colors of ink attached thereto, which is inserted between the head and the receiver and moved in synchronization with the receiver during transfer;
The ink of the ink donor film is selectively transferred to the receiver by the thermal print head while rotating the drum and moving the receiver while the gripper is in a fixed operating state.

[Operation] According to the above configuration, the drum holds the receiver therein so as to be able to be pulled out, and the pulled out receiver is sent out onto the outer periphery of the drum through the opening. Then, the thermal print head can press a predetermined portion of the ink donor film onto the outer peripheral surface of the drum with the ink donor film stacked on the receiver. In this state, by rotating the drum, the receiver can be moved relative to the thermal print head, and during this movement, ink from the ink donor film can be selectively transferred onto the receiver.

In this manner, the drum according to the present invention can perform two functions: as a receiver holding means for holding the receiver and as a platen drum disposed opposite to the thermal print head.

Therefore, the movement of the receiver during transfer can be accurately controlled by controlling the rotation of the drum, and the transfer area can be accurately set. As described above, since the holding means for the platen drum and the receiver are constructed of one member, the number of parts can be reduced, thereby simplifying the structure and downsizing the entire apparatus.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

First Embodiment FIG. 1 is a schematic cross-sectional view showing the overall configuration of the first embodiment, and the same elements as in the configuration of the conventional device shown in FIGS. 5 and 6 are given the same reference numerals. ing.

In the figure, the drum 32 has a hollow structure, and a receiver holding shaft 32b is formed coaxially with the drum 32 inside its outer wall 32a, and the receiver 10 is wound and laminated around the receiver holding shaft 32b.

A receiver passing slit 34 is formed in the outer wall 32a of the drum, and the laminated and wound receiver 10 is sent out onto the outer peripheral surface of the drum 32 through this slit. This feeding of the receiver 10 is carried out by the roller 3.
6, a feed roller 38 formed near the receiver passage slit 34, and a small roller 4 disposed opposite thereto.
It is done by 0. That is, the receiver 10 is inserted into the gap between the rollers 38 and 40, and further guided onto the outer peripheral surface of the drum 32 through the receiver passing slit 34. Further, in this embodiment, a gripper 42 is installed inside the drum 32. This gripper 42 fixes the receiver 10 by pressing it against the inner wall surface of the drum outer wall 32a,
Alternatively, by moving away from the outer wall 32a, the receiver 1
It is switched so that 0 is the released state. gripper 4
2 is in a fixed operation, the receiver 10 moves with the rotation of the drum 32. Further, when the gripper 42 is in the fixing release operation, the receiver passage slit 3 of the drum of the receiver 10
It is possible to withdraw and send out from 4.

Further, a cutter 44 is attached to a position further in the sending direction of the receiver 10 than the receiver passing slit 34 of the drum outer wall 32a so as to be able to rotate together with the drum 32. In this embodiment, the cutter piece 44a and 44b are composed of two cutter pieces 44a and 44b.
4a, and the receiver 10 is cut by the contact movement of both pieces.

The thermal print head 18 is installed near the drum 32, and is configured so that its transfer portion can press against and separate from the drum 32.

Further, the ink donor film 20 is inserted between the receiver 10 and the thermal print head 18 as in the conventional example.Next, the operation of this embodiment will be explained.

First, the receiver 10 is loaded onto the receiver holding shaft in the drum 32 in a laminated and wound state. In this loading operation, one bottom surface of the drum 32 is made openable, and the receiver 10 is loaded from the open side. At this time, the gripper 42 is in the unfixed state, and the winding end of the receiver 10 is passed between the gripper 42 and the inner peripheral surface of the drum outer wall 32a and inserted between the feed roller 38 and the small roller 40. loaded. Further, in this state, the thermal print head 18 is separated from the drum 32. Here, the receiver 10 is sent out through the receiver passing slit 34 by the operation of the feed roller 38, passes through the cutter 44, and is sent out onto the outer peripheral surface of the drum 32. This feeding of the receiver 10 onto the outer peripheral surface of the drum 32 is continued until a predetermined length is reached. During this time, the ink donor film 20 is wound up to a predetermined position (a predetermined color area) by the film roller 22. Then, the gripper 42 performs a fixing operation to fix the receiver 10 to the drum 32.

In this state, the transfer preparation operation is completed.

Next, in the transfer operation, the thermal print head 18 is pressed against the drum 32 with a predetermined pressure, the drum 32 is rotated clockwise, and the thermal transfer is performed by the thermal print head 18 while the receiver 10 is moved along with the rotation. The rotation of the drum 32 during transfer is controlled by a drum rotation drive unit and drum rotation angle detection means (not shown). By accurately controlling the rotation of the drum 32, it becomes possible to directly set the transfer position of the receiver 10 with high precision. Further, the transfer area to the receiver 10 can be adjusted by adjusting the rotation angle of the drum 32, and can easily correspond to the size of the receiver 10.

Furthermore, since the receiver 10 can be moved only by rotation of the feed roller 38 and the drum 32,
There is no need to provide a transport mechanism for transporting the receiver 10, and the configuration of the printer can be extremely simplified.

First, when the first color transfer is completed, the thermal print head 18 is returned to the separation position, the ink donor film 20 is wound up to a predetermined color position by the film roller 22 or 24, and preparation for printing the second color is completed. It will be done. Here, the tram 32 is rotated counterclockwise and returned to the transfer starting position again. The receiver 10 is the gripper 4
2, the transfer start position is accurately set by the counterclockwise movement of the drum 32. Here, an operation similar to that for the first color is performed, and the second color transfer is completed. This operation is repeated as many times as the colors to be transferred. for example,
In the case of three colors, yellow, magenta, and cyan, the above printing operation is repeated three times.

When the printing of the first sheet is completed, the receiver 10 is cut into a predetermined length by the cutter 44.

Then, in preparation for transferring the second sheet, the feed roller 3
8 sends out the receiver 10 by a predetermined length onto the outer periphery of the drum 32. The feeding of the receiver 10 by a predetermined length is controlled by rotating the feed roller 38 or by detecting the position of the tip of the receiver 10 with a photointerrupter or the like.

Second Embodiment FIG. 2 is a schematic sectional view showing the overall configuration of the second embodiment, and the same elements as in FIG. 1 are given the same reference numerals and their explanations will be omitted.

The difference between this embodiment and the first embodiment is that the cutter 44
Rather than being provided on the drum 32, it is provided at a position a predetermined distance away from the drum 32.

In this embodiment, after printing the first sheet, the feed roller 38 further feeds out the receiver 10.
The receiver feed length is detected by an edge sensor (not shown) that detects the tip of the receiver 10, and the receiver 10 passing through the cutter 44 is cut when a predetermined length is reached. Further, after the gripper 42 is set in the fixed release state and the receiver 10 is fed out a predetermined length by the feed roller 38, the gripper 42 is set in the fixed state and the drum 32 is
It is also possible to send the receiver 10 to the cutting position by rotating it counterclockwise by a predetermined angle.

According to this embodiment, since it is not necessary to provide the cutter 44 on the drum 32, the structure of the drum 32 can be simplified.

Other Embodiments FIGS. 3 and 4 show other embodiments, in which the cutter 44 is provided at a predetermined distance from the drum 32 and the gripper 42 is provided outside the drum 32. . With this configuration, the internal configuration of the drum 32 can be further simplified, and manufacturing can be facilitated.

Further, in the embodiment shown in FIG. 4, the winding center of the receiver 10 held within the drum 32 is set at a position offset from the rotation axis of the drum 32. With this configuration, the distance from the wound receiver 10 to the receiver passage slit 34 can be shortened, and the receiver 10 can be easily set.

In the embodiments shown in FIGS. 3 and 4, the feed roller 38
Also, the small rollers 40 are not provided, and the receiver 10 is pulled out manually.

[Effects of the Invention] As explained above, according to the color thermal printer according to the present invention, the drum has the function of a platen roller, the function of holding the receiver, and the function of moving the receiver. Simplification and a reduction in the number of parts can be achieved, and the device can be made smaller.

Furthermore, by controlling the rotation of the drum, it is possible to convey the receiver and set the transfer position with high precision.
Printing performance of a color thermal printer can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing the overall structure of the first embodiment, FIG. 2 is a schematic sectional view showing the overall structure of the second embodiment, and FIGS. 3 and 4 are schematic sectional views showing other embodiments. The cross-sectional view, FIGS. 5 and 6 are explanatory diagrams showing the schematic structure of a conventional color thermal printer. 10...Receiver 8 2 8 2 4

Claims (1)

[Claims] (1) It is installed so that rotation can be controlled, and is provided with a holding means for holding an image receptor, which is a transferred object, in a freely drawn out, laminated and wound manner, and on a peripheral wall, the image receptor from the holding means is placed on the outer periphery. a drum provided with an opening for feeding; a gripper configured to rotate together with the drum and switchable to fix or release the pulled-out image receptor from the drum; and a gripper located near the drum. a thermal recording head capable of pressing a predetermined portion of the image receptor placed on the outer periphery of the drum onto the outer periphery of the drum; and a thermal recording head inserted between the thermal recording head and the image receptor and synchronized with the image receptor during transfer. a transfer type recording medium having a plurality of colors of ink adhered thereto, which is moved by the gripper, and the ink on the transfer type recording medium is transferred by the thermal recording head while the drum is rotated and the image receptor is moved while the gripper is in a fixed operating state. A color thermal printer characterized by selectively transferring images onto an image receptor.