JPS59188451A - Transfer type thermal color recorder - Google Patents

Abstract

PURPOSE:To shorten the speed of recording while keeping the printing quality good without causing slipping of recording paper even when a gripper is released within one rotation of a feeding drum by using a system in which a press roller is provided just before releasing the gripper of recording paper for ensuring the feeding force of the paper. CONSTITUTION:A recording paper 1 is held by a gripper 31, recorded with a mixture of IDF inks of colors according to the picture information of line thermal heads 74, 75, and 76 while being fed, and passed through a press roller 10. When the recording paper 1 is pressingly contacted with a feeding drum 3 by the press roller 10 at a given pressure by a spring 12, grapsing of the gripper 31 is released and the paper 1 is supplied from a waste paper guide 9 to a waste paper tray. Although the rear of the paper 1 is still in a state of being recorded at this time, a feeding force overcoming load encountered in recording can be obtained by the pressing force of the press roller, and therefore, the slipping of the recording paper 1 can be prevented.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention has a plurality of ink donor films of different colors and a line thermal head disposed corresponding to each ink donor film. Transfer-type thermal color recording, in which the ink of each color ink donor film is transferred independently at a location where heat is generated in accordance with an image signal of a thermal head, and color recording of seven colors is performed by overlapping each of the transfer inks. Regarding equipment.

[Prior art]

2. Description of the Related Art In recent years, a transfer-type thermal color recording device using a line thermal head, which has a high recording speed and a relatively simple mechanism, has been adopted as a recording device for color copying machines, color facsimile machines, and the like.

FIG. 1 is a schematic plan view showing an example of such a transfer-type heat-sensitive color recording device, and its main components include a recording paper conveying roller 2 and a gripper 31. A transport drum 3 having a conveyor drum 3, yellow, cyan, and magenta color ink donor films (hereinafter referred to as I
(abbreviated as DF) 4.5.6, line thermal head 74.
75, 76 and a paper discharge guide 9. In this device, an elastic body such as NR (natural rubber) is formed on the surface of the conveyance drum 3, and the recording paper 1 and each color IDF 4 are formed on the surface of the conveyance drum 3.
．． 5.6. The adhesion between the three line thermal heads 74, 75, and 76 is improved, and the conveyance of the recording paper is also improved. The yellow, cyan, and magenta colors IDF4.5.6 are the recording paper 1.
The line thermal heads 74, 75, and 76 each having a heating element having the same width are pressed against the conveying drum 3 by a pressing mechanism (not shown). Furthermore, each of the line thermal heads 74, 75, and 76 also has a mechanism that can adjust the distance between each head in the feeding direction of the recording paper 1. In such an apparatus, recording of a color original is performed as follows. When the waste handler turns on the drive switch, the conveyance drum 3 is rotated at a predetermined speed by a rotating means (not shown). Then, the recording paper is fed by the rotation of the transport roll 2 at a predetermined timing of the rotation.
After that, the recording paper IFi is conveyed following the 30 rotations of the conveyance drum, first yellow IDF 4, then line thermal head 74.
The information is supplied to the @department.

An image signal of a color document read by a cutting device (not shown) is applied to the line thermal head 74, and the ink of the yellow IDF 4 is melted at a location where heat is generated in response to the image signal, and the ink of the yellow IDF 4 is melted at the desired location. The image is transferred onto recording paper 1. Subsequently, the yellow ink was not transferred fi7
(Recording paper) is supplied to the recording section including the cyan IDF 5 and the line thermal head 75 as the conveyance drum 3 rotates. As above, the line thermal head (3) 75 generates heat in accordance with the image information. Further, the recording paper is supplied to a recording section including a single magenta IDF 6 and a line thermal head 76, and a magenta color transfer is performed at a heat-generating portion according to the image information of the line thermal head 76.

As described above, a seven-color recording of a desired color original was performed by mixing the respective color inks transferred to the recording paper IK by thermal transfer recording via the IDF of each color. When all recording of the color document is completed, the grip of the recording paper by the gripper 31 is released just before the paper ejection guide 9, and the recording paper on which the recording has been completed is transferred to a paper ejection tray (not shown) via the paper ejection guide 9. It is taken out at □.

In such a transfer-type thermal color recording device, each color IDF ink of yellow, cyan, and macenta is transferred independently, and the seven colors of a color original are reproduced by superimposing these inks. Therefore, in order to maintain good recording accuracy, the positional deviation of each pixel should be 50 to 100.
Therefore, the recording paper conveyance mechanism of this apparatus was required to have a particularly high precision. The gripper 3 is used to prevent the transfer position from being caused by a load (reverse force generated by the pressing force of each line thermal head 74, 75, 76 against the conveyance drum 3) applied to the recording paper 1 when marking the needles. This is a diagram of the anti-slip mechanism for the feeding drum 3 and the recording paper 1. By the way, in order to improve the recording accuracy and shorten the vc recording speed as described above, it is desirable to release the grip of the recording paper 1 by the gripper 3117j while the rotation of the conveyance drum is as small as possible.

However, in the conventional apparatus mentioned above, it is necessary to rotate the conveyance drum 302'fr in order to release the grip of the Fi recording paper, and therefore it cannot contribute to the reduction of the recording speed (11').

In other words, when the grip on the recording paper 1 is released during rotation of the transport drum, most of the recording paper is still being printed, so the above-mentioned gripper 31 has no slip prevention function, and the V-feed drum 3 and There was an inconvenience that the transfer position was shifted due to the slip with the recording paper 1, which significantly reduced the recording performance. 6. A method of releasing the gripper after the above-mentioned transport drum is rotated twice and printing is completely completed. Another method that can be considered is to make the diameter of the conveyance drum extremely large so that printing can be completed within one rotation, but in this case as well, it is not practical from the viewpoint of cost and thickness of the device. It was a disadvantage.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a transfer-type thermal color recording device equipped with a recording paper conveyance mechanism capable of tilting the recording speed while maintaining good print quality. is its purpose.

[Printing of invention]

Therefore, in the present invention, a recording paper pressure contact roller is provided for pressing the recording paper against the conveyance drum immediately before the gripper release position of the recording paper, and the pressure force of the needle paper pressure contact roller is used to record a and a after the gripper is released. The conveyance force for the paper is ensured so that slippage between the conveyance drum and the recording paper does not occur even if the gripper for the recording paper is released within one revolution of the conveyance drum.

[Embodiments of the invention]

Embodiments of the present invention will be described in detail below based on the accompanying drawings. FIG. 2 is a schematic plan view of a transfer type thermal color recording apparatus showing an embodiment of the present invention, and parts having the same functions as those in FIG. 1 are designated by the same reference numerals. According to this apparatus, a VC recording paper pressing roller 10 is newly disposed immediately before the paper ejection guide 9, and the third area shows an enlarged schematic diagram thereof. As shown in FIG. 3, the needle paper pressing roller 10 is rotatably attached to an arm 1 rotatable about a fulcrum f by a shaft g, and is pressed against the conveying drum 3 by a spring 12.

As mentioned above, the recording paper 1 is gripped by the gripper 31, and the line thermal head 74 independently applies to the recording paper 1.
．． Mixed recording is performed by transferring the yellow, cyan, and magenta color IDF inks corresponding to each line thermal head (7) at the heat-generating locations corresponding to the image information of 75 and 76, while the rotation of the conveyance drum 3 and The recording paper press roller 1 is rotated and conveyed.
0'f passes. Here, the recording paper 1 also has a spring 12
The recording paper is pressed against the transport drum 3 with a predetermined pressure by the recording paper pressing roller 10 . Immediately after the recording paper 1 passes the recording paper pressure contact roller 10, the grip by the gripper 31 is released and the recording paper 1 is supplied to a paper discharge guide 9 and a paper discharge tray (not shown).

At this point, since the rotation Vi of the conveyance drum 3 is less than one rotation, the recording sheet 1 is in the recording state at the rear Fit.

However, according to the apparatus of the present invention, the load associated with the recording (
A conveyance force that overcomes the reverse conveyance force generated by the pressure force of each thermal head can be obtained by the pressure force of the recording paper pressure contact roller 10, and when the gripper of the recording paper 1 is released after passing through the recording paper pressure contact roller 1°. Also, slippage between the conveyance drum 3 and the recording paper 1 can be prevented (8). That is, in FIG. 3, the separation angle between the recording paper pressure contact roller 0 and the nip 13 of the line thermal head 76 as viewed from the cylindrical center 0 of the conveyance drum 3 is α, and the distance between the recording paper pressure contact roller 10 and the conveyance drum by the arm 11 is α. 3, and the friction coefficient between the surface of the transport drum 3 and the recording paper is μ, then the pressure force P applied from the spring 12 and the pressure F of the recording paper 1 against the transport drum 3 are A relationship is established between them. Further, the pressure contact point t of the recording paper pressure contact roller 10 obtained from the pressure contact force FK and the thermal head nip arrangement point 1. Conveying force T, (= μF
) and T2, the following relationship holds true: Q). Here, if NR (natural rubber) is formed on the surface of the conveyance drum 3, the friction coefficient μ becomes μζ1, so the formulas (1) and (2) can be expressed as, respectively, the F/ P, Tt/F and the pressure bonding force β,
The relationship with the separation angle α is shown in Fig. 4 1 (a) and Fig. 4 (
The relationship shown in b) above (]) and (
2) From the equation, the pressing force P by the spring 12 and 1. ．． 1.
The relationship between the recording paper conveyance force Tt and Tt at point Vc is expressed by equation (1'), equation (J'), and equation (2'). Now, if the separation angle α and the crimp angle β mentioned above are nα=90 and β=60, then from equations (3) and (4), Tt # 2.73 P% T ζ] 1. 38 P
becomes. Therefore, at this time, at the pressure contact point t of the recording paper conveyance roller 10 on the conveyance drum 3, the conveyance force is approximately three times as much as the pressure force P of the spring 12, and at the point t2 where the rad nip 12 is disposed on the shredded thermal paper, the pressure force is A conveying force more than 10 times that of P can be obtained. Therefore, even if the gripper of the recording paper l is released within one rotation of the conveyance drum 3 and the paper is immediately ejected, the print quality will not be impaired.

Of course, the separation angle α and the crimp angle β can be arbitrarily selected. Furthermore, the order of transfer of each color transfer heat-sensitive recording section to the transport drum may be arbitrary.

〔Effect of the invention〕

As explained above, according to the uninvented transfer-type heat-sensitive color recording device, the conveying force 'f of the recording paper after the gripper is released is obtained by the pressure force of the recording paper pressing roller, so that the gripper is Even when released, no slip occurs between the conveyance drum and the recording paper, which provides an excellent effect of realizing high-speed color recording without brownish deviation.

[Brief explanation of drawings]

FIG. 1 is a schematic plan view showing a conventional transfer-type heat-sensitive color recording snowmaking system, FIG. 2 is a schematic plan view showing a transfer-type heat-sensitive color recording apparatus according to the present invention, and FIG. 3 is a schematic plan view showing a recording paper according to the present invention. FIGS. 4(a) and 4(b) are diagrams illustrating an enlarged view of the pressure roller; FIGS. 1... Recording paper, 2... Conveyance roller, 3.
...Conveyance drum, 4--Yellow ink donor film, 5--Cyan ink donor film,
6-...Magenta ink donor film, 74.75
．． 76...-Line thermal hect, 9... Paper discharge guide, ]0... Recording paper pressure roller. JP-A-59-188451 (5) Figure 4 (G) β word (b) Φ

Claims (1)

[Claims] Independent transfer thermal recording comprising a plurality of line thermal heads on the surface of a recording paper transport drum, and ink donor films of different colors interposed between each of the two thermal heads and the recording paper transport drum. and a gripper for gripping the recording paper on the surface of the recording paper transport drum, the recording paper being gripped by the gripper and being fed following the rotation of the recording paper transport drum. In the transfer-type heat-sensitive color recording device, in which each ink donor film ink is transferred independently in each of the transfer heat-sensitive recording sections and a color document is recorded by superimposing the transfer inks, immediately before the recording paper release position by the gripper. A transfer type thermal color recording device, characterized in that a recording paper pressure contact conveyance roller is provided for pressing the recording paper against the recording paper conveyance drum.