JPH0525891Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The invention is based on the invention, by passing a recording paper over a thermal head consisting of a heating element that selectively generates heat according to image information, overlapping an ink donor film. The present invention relates to a transfer type thermal recording device that transfers ink to the recording paper, and particularly relates to means for detecting the amount of movement of the recording paper.

Conventional technology In the transfer type thermal recording method, an ink donor film, which is a polyester film coated with heat-melting or heat-sublimating ink on one side, is used as a recording medium, and image information is transferred from a thermal head to this ink donor film. An image is recorded by selectively supplying heat and transferring ink melted by the heat onto paper. This transfer-type thermal recording method can be achieved by preparing multiple sheets coated with ink of different colors as ink donor sheets, and sequentially performing thermal transfer recording on a single sheet of paper using these ink donor films. A multicolor record can be obtained.

Apparatuses that perform such multicolor recording include those using a multi-pass method and those using a single-pass method.

The multi-pass multicolor transfer thermal recording device is
It is equipped with one recording section, and the operation of supplying one sheet of paper and a plurality of ink donor films to the recording section is repeated for each color to perform recording.

On the other hand, a single-pass type multicolor transfer type thermal recording device is equipped with a plurality of recording sections, and can perform multicolor recording by feeding the sheet once.

FIG. 15 shows an example of a conventional single-pass multicolor transfer type recording apparatus.

This device has four sets of recording sections: a first recording section M that records in magenta, a second recording section Y that records in yellow, a third recording section C that records in cyan, and 4th recording in black
The recording section B is provided with a recording section B, and each recording section M, Y, Multicolor recording is performed by supplying image signals corresponding to C and B. In each recording section, for example, to explain the first recording section M, there is an ink donor film 5a with magenta ink applied to a base paper, and a first supply roll 3 that supplies the magenta ink donor film 5a.
a, a first thermal head 1a that contacts the first backroll 2a via the supplied magenta ink donor film 5a, and a first thermal head 1a that collects the magenta ink donor film 5a after transfer.
A first recording section M is constituted by the take-up roll 4a. In this apparatus, the paper is conveyed in a superimposed state on the ink donor film 5a by the action of the drive roll 6a of the ink donor film 5a, and magenta recording is performed. For recording after the second yellow color, an image signal delayed by a preset time according to the paper running speed and the distance from the first recording section is supplied, and image alignment at each recording section is performed. It will be done.

Problems to be solved by the invention In the former of the above transfer type thermal recording devices, that is, the multi-pass type, the image alignment operation when repeatedly recording each color on a single sheet of paper is complicated. There is a problem that.

On the other hand, in the latter single-pass type multicolor transfer thermal recording device, the paper is moved by independent drive rollers 6a, 6b, 6c, and 6d in each recording section.
Because this is done by driving the rollers, the amount of paper conveyance tends to vary due to subtle differences in the diameter of these drive rollers, coefficient of friction, etc. This has the disadvantage of causing color misalignment due to overlapping, which deteriorates the quality of the recorded image. It was hot.

There is also an encoder connected to the back rolls 2a and 2d to detect the rotational speed of the back rolls 2a to eliminate misalignment of each color.
There was a problem of lack of accuracy due to the thermal influence of 1d.

On the other hand, as shown in Japanese Patent Application Laid-Open No. 18362/1983, a detection means for contacting the recording paper and detecting its running condition is provided upstream of the summer head in the running direction of the recording paper, and this detection means There is a device in which the ink donor film drive means is controlled according to the output, but in this conventional technology, the detection means is located upstream of the thermal head in the traveling direction of the recording paper, and the detection means is located upstream of the thermal head in the traveling direction of the recording paper. Due to the contact structure, the following problems arose.

In other words, although the running speed of the ink donor film and the feeding speed of the recording paper are naturally synchronized,
Since only the amount of movement of the recording paper is detected before it merges with the ink donor film, if the recording paper is curled or wrinkled, the detected amount may deviate from the amount of movement of the ink donor film, so it cannot be accurate. There was a problem that it could not be detected. Furthermore, in order to prevent the recording paper from skewing in this area, the rollers constituting the detection means need to nip almost the entire width of the recording paper, which increases the inertial mass of the detection means and increases the There is a problem in that an error occurs in detecting the amount of movement.

Means and Effects for Solving the Problems The present invention has been made in view of the above, and includes a thermal head 152, a back roll 153 which presses the recording paper 153 and the ink donor film 51 between them, and an ink donor. film 51
The recording paper 153 passes between these rollers 301 and 302. In a transfer-type thermal recording apparatus, which has a detection means for detecting the amount of movement of the recording paper 153 by the rotation of the detection roller 301, and a control means for controlling the ink donor film drive means according to the output of the detection means, The above detection means is connected to the ink donor film 51 and the recording paper 15.
The ink donor film 51 and the recording paper 154 are sandwiched in an overlapping state between the separation part from the printer 4 and the thermal head part, and the ink donor film 51 that has passed through the thermal head part The recording paper 154 and the recording paper 154 pass between the detection roller 301 and the pinch roller 302 of the detection means in a state in which they are closely overlapped, and the detection means moves the recording paper 154 by the same amount of movement as the ink donor film 51. amount is detected.

Embodiment An embodiment of the present invention will be described based on FIGS. 1 to 14.

FIG. 1 is a schematic diagram illustrating the configuration of a color copying apparatus using thermal transfer recording according to an embodiment of the present invention. and a color recording section 2 for obtaining a color recorded image.

The image reading section 1 includes a fixed platen 6 on which a document is placed, fluorescent lamps 14, 15, and 16 that move back and forth to read the document, a plane mirror 18a for guiding light reflected from the surface of the document, and a plane mirror. 18
b, 18c, a lens 4 for forming an image of the guided reflected light, an image sensor 5 for converting the optical image into a corresponding electric signal, and the fluorescent lamp unit and plane mirror unit are reciprocated. It is composed of a drive motor 10 and the like for the purpose.

In order to perform color reading of a document, in this embodiment, the fluorescent lamps 14, 15, and 16 are each equipped with blue, red, and green filters, which are arranged at predetermined intervals. . As for the positions of each member of the image reading section 1 in FIG. 1, the position at which document reading starts is shown by a solid line, and the position at which reading ends is shown by a chain line.

On the other hand, the color recording section 2 includes a yellow supply roll 55 in which a yellow ink donor film (hereinafter abbreviated as IDF) 51 for performing yellow recording is wound around a paper tube.
Magenta color IDF for recording magenta color
A magenta color supply roll 56 in which a cyan color IDF 53 is wound around a paper tube in a roll shape, a cyan color supply roll 57 in which a cyan color IDF 53 for cyan color recording is wound in a roll shape around a paper tube, and a black color recording medium. Four sets of black supply rolls 58 each having a black IDF 54 wound around a paper tube are provided for carrying out this process.

Next, the configuration of the transfer section of the recording section 2 will be explained using the yellow recording section, which is the first recording section, as an example. Note that the configurations of the transfer portions of other colors are also the same as or equivalent to the configuration of the yellow transfer portion.

FIG. 2 shows a structural diagram of the yellow transfer portion.

This device is equipped with a yellow supply roll 55 and a take-up roll 151.
The long IDF 51 is continuously supplied to the winding roll 151, and is collected onto a take-up roll 151 after use. Pack crawl 153 is IDF5
1 and the recording paper 154 overlapped in front of the heating element section 303 are pressed against the thermal head 152. Furthermore, the heat sink 500 attached to the thermal head 152 is connected to the heating element 303.
Since the temperature of the thermal head 152 itself rises due to the heat generated by the thermal head 152, it functions to release this heat, and may be constructed of a heat pipe or the like. Also, fans 510 to 5 attached to each recording section in FIG.
13 also works to lower the temperature of the thermal head.

The IDF 51 is a heat-resistant film such as polyethylene tereftate (PFT) with a thickness of 3.5 μm and one side coated with 2.5 g/cm ² of thermofluidic ink (melting point 70°C, for example), and the thermal head 152 is selectively driven. Then, the fluidized or sublimated ink is transferred to the recording paper 154, and thermal transfer recording is performed. After this, the IDF 51 and the recording paper 154 continue to move along the circumferential surface as the back roller 153 rotates. Then, the two are separated by the separation bar 304, the IDF 51 is wound up on the take-up roll 151, and the recording paper 154 is sent in the direction of the arrow in the figure.

The conveyance of the recording paper 154 in each recording section is IDF5.
This is done by the frictional force with 1. The IDF 51 is conveyed by driving the drive roll 155 by a stepping motor 400.

The explanation will be given by returning to FIG. 1 again.

The recording paper 154 is sent from trays 61 and 62 to a yellow recording section by feed rollers 63 and 64, and yellow information is printed thereon. Next, recording is performed in the order of magenta, cyan, and black, and after all four colors have been recorded, the paper is sent to the discharge tray 60 by the discharge roller 59.

Next, a case where only black is recorded by the fourth recording section will be described. Details of section A in FIG. 1 are shown in FIG. 3.

In Figure 3, when recording only black records,
The switching plate 31 is switched to the solid line position, and the recording paper fed from the direction a is not transported to the path b to the yellow recording section, but is sent to the path c to the black recording section, printed, and discharged. It is sent out to the tray 60.

By doing this, you can print yellow,
It is possible to save cyan and green IDF.

Next, how to replace and set the IDF 51 will be explained. FIG. 4 is an exploded perspective view showing the IDF replacement of the yellow recording section in this apparatus, and the same is true for the other recording sections.

The IDF cassette 502 includes a supply roll 55 wound around a paper tube 506, and a take-up roll 151 from which the IDF 51 sent out from the supply roll is wound onto a paper tube 507 and collected after the ink is transferred onto recording paper by a thermal head. It has a structure in which paper tubes 506 and 507 of a supply roll 55 and a take-up roll 151 are rotatably supported in a box-shaped cassette case 503, respectively.

The IDF cassette 502 is a drawer-shaped guide 50 that slides in and out of the device body 500.
It is designed to be detachably held at 1.
On the other hand, the guide 501 itself has a pair of slide rails 504 that can move in and out of the device body 500.
It is adapted to be able to move in and out of the device main body 500 by engaging with the device body 500. The cassette case 503 is provided with a handle 508 that is used when the IDF cassette 502 is attached to or removed from the guide 501, and the guide 501 is provided with a handle 505 that is used when the guide 501 is slid.

When setting the IDF cassette 502, insert the IDF into the guide 501 pulled out from the main body 500.
After installing the cassette 502, when the guide 501 is pushed into the device main body 500, the guide 501 and
The IDF cassette 502 is inserted into the apparatus main body 500 and set.

When replacing, just perform the above steps in reverse.

Next, the image signal forming device has a configuration as shown in FIG.

By blinking the blue, red, and green (hereinafter referred to as B, R, and G) filtered fluorescent lamps 14, 15, and 16 of the reading unit 1, the B, R, and G of the original on the platen 6 are displayed. The information is read by the image sensor 5, converted from analog to digital signal (7 bits) by the A/D converter 510, and corrected by the shading correction 511. This B,
The R and G signals are accurately converted into B, R, and G signals in the next color separation device 512. This is because the filter has a wide range of spectral characteristics. The B, R, and G signals are converted to density by a Log converter 513.
Next, the density and color modulator 514 performs modulation such as making the density lighter or darker, and color modulation, for example, making red when it has a red color. This specification is made using a switch on the operation panel. Next, in the masking device 515, B,
The R and G signals are converted into yellow, magenta, and cyan (hereinafter abbreviated as Y, M, and C) signals, and the UCR unit 516 determines the amount of black ink K to be used. By using black ink, it is possible to develop colors in high-density areas that could not be achieved with Y, M, and C alone, and by replacing Y, M, and C inks with K, ink can be saved.

The Y, M, C, and C signals (7 bits each) are sent to a halftone processing device 517, where dither processing and the like are performed to express gradation, and the Y, M, C, and K signals become binary signals. .

The next delay memory 518 is a memory between each recording section, and the first recording section (Y) does not require a memory.

Next, the print data is corrected by the thermal storage correction 519 for the applied energy for printing with the thermal head. For example, the optimal printing pulse width or the voltage applied to the thermal head is determined in consideration of the substrate temperature of the thermal head, peripheral data to be printed, etc.

The data corrected by the heat storage correction device 519 is transferred to the thermal head 520 and recorded. Y,
Color recording is expressed by printing overlapping M, C, and K.

The overall control device 521 performs the series of controls described above. Also, as shown in FIG. 6, the data is transferred to each recording section (thermal head). The flow of Y, M, C, and K data is shown.

Next, the detection roller 301 shown in FIG. 2 will be explained. This detection roller 301 is connected to the recording paper 154.
The IDFs 51 are stacked and conveyed from the heating element section 303, and separated from the recording paper 154 by the peeling bar 304.
Until the IDF 51 is peeled off, the recording paper 154
As shown in FIG. 7, the detection roller 301 is rotatably attached so as to be in contact with the detection roller 301, and as shown in FIG.
Use tungsten carbide with a grain size of 75 to 150 μm as the material, and obtain a 10-point average roughness of 40 to 50 μm. In addition to thermal spraying, grid-like aluminum oxide may be adhered to the surface to give a 10-point average roughness of 40 to 50 μm. Further, an encoder 306 is connected to the detection roller 301 via a shaft 305, and is adapted to detect the angular velocity of the detection roller 301.

Also, a recording paper 154 is placed opposite the detection roller 301.
A pinch roller 302 is arranged to sandwich the IDF 51. As shown in FIG. 7, this pinch roller 302 has a shaft 307 with chloroprene rubber (hardness 60°) wrapped around the middle portion thereof. Further, as shown in FIG. 8, both ends of the shaft 307 are rotatably supported by levers 308a, b which are rotatably supported by pins 309a, b. The levers 308a, b are biased in a direction to press the pinch roller 302 against the detection roller 301 by springs 310a, b attached on the opposite side from the pinch roller 302. Appropriately, this biasing force is about 2 to 2.5 kg.

When the recording paper 154 is conveyed in this state, the detection roller 301 has a protruding rough surface as described above, so the recording paper 154 follows without slipping, and the angular velocity of the encoder 306 The amount of movement of the recording paper 154 is calculated.

Next, a method for separating the pinch roller 302 from the detection roller 301 will be explained with reference to FIGS. 8 and 9.

The pinch roller 302 is connected to the lever 3 as described above.
08a, b via pins 309a, b, and the pins 309a, b are fixed to both sides of the swinging frame 320, so the swinging of the swinging frame 320 causes the pinch roller 302 to
is also spaced apart from the detection roller 301. Further, when separated, the levers 308a and 308b are stopped by a stopper 308 attached to the side of the swing frame 320, and the pinch roll 302 no longer swings relative to the swing frame 320, and the levers 308a and 308b are stopped by a stopper 308 attached to the side of the swing frame 320. to sway.

Next, a method of swinging the swing frame 320 will be explained.

A latch pin 3 is attached to the side of the swing frame 320.
22 is provided in a protruding manner, and a pawl 327 of a latch lever 325 engages with this latch pin 322 to hold the swing frame 320 in a fixed position.

The latch lever 325 is provided so as to be able to swing via a shaft 326 at its upper part.The latch lever 325 is swingable clockwise by a solenoid 328, and when the solenoid 328 is released, the latch 327 is moved by a spring 329. It returns to the position where it engages the latch pin 322.

Further, a drive device 330 provided at the lower part of the swing frame 320 is composed of large and small gears 332, 333 rotated by a motor 331, and a fan-shaped gear 334 that meshes with the gear 333.
The gear 334 is oscillated by one forward and reverse rotation.

An arm 335 is fixed together with a gear 334 to a shaft 336 rotatably supported by a frame (not shown), and is formed to swing together with the arm 335. An arm 335 has a link 337 at its end via a fulcrum 338 The upper part of this link 337 is connected to the swing frame 320 via a fulcrum 339. With this configuration, when the motor 331 is driven, the swing frame 320 swings about the swing center shaft 321 via the gear 334 and the arm 325.

Next, the operation of each of the above-mentioned members will be explained. When recording image information, the swing frame 320 is moved so that the latch pin 322 is connected to the latch lever 32.
5 and is fixed in the position shown by the solid line in FIG.
52 and a back roller 153, the ink donor film 51 and the recording paper 154 are sandwiched between the ink donor film 51 and the recording paper 153, and the donor on the film is heated by the heating device and transferred onto the recording paper 154. perform the following actions.

When replacing the ink donor film 51 or when removing a paper jam in the recording paper 154, pressing the operation button provided on the keyboard of the thermal recording device will cause the First, the solenoid 32 is
8 is energized, the latch lever 325 is rotated clockwise, and the engagement between the latch 327 and the latch pin 322 is released. Next, the motor 331 is energized to start driving, the arm 335 is rotated clockwise via the gears 332, 333, 334, and the swing frame 320 is further swung downward via the link 337. , the swing frame 335 stops at the position shown by the chain line, and predetermined work is performed in that state.

If you want to reset the swing frame 320 after replacing the ink donor film or removing the paper, press the operation button on the keyboard again, or press the reset button provided separately. By pressing a button or the like, the power to the solenoid 328 is cut off via the above-mentioned control device, the latch lever 325 is returned to its original position by the spring 329, and then the motor 33
Rotate 1 in the opposite direction.

Therefore, the swing frame 320
21 in the clockwise direction, and returns to the original position shown by the solid line, and the latch pin 322 locks the latch 32.
7 will be locked.

Next, the concept of adjusting the speed of the motor 400 will be described.

The detection roller 301 rotates as the recording paper 154 is conveyed, and the detection roller 301 rotates from an arbitrary reference point.
It is detected that the recording paper 154 has moved by 1/8 of a rotation, and this is taken as a check point. Time measurement is started from the above reference point, and at each check point, the cumulative time from that reference point is measured.
At this time, the distance between the check points is assumed to be known.

For example, as shown in FIG. 10, the measurement time tm (n-1) at the (n-1)th check point is the same as the measurement time tm (n-1) at the (n-1)th check point when the recording paper 154 is conveyed at the ideal speed. Check point arrival time ti(n
-1). After that, recording paper 1
54 moves by 1/8 rotation of the detection roller 301,
As shown in FIG. 10, the measured time tm (n) when reaching the (n)th check point deviates from the arrival time ti (m) when the recording paper 154 is conveyed at the ideal speed due to disturbances, etc. (delayed in this case)
When this occurs, the motor is set so that the next (n+1)th checkpoint matches the (n+1)th checkpoint arrival time ti(n+1) when the recording paper 154 is conveyed at the ideal speed. Adjust the drive cycle of 400.

Let T be the cycle of the motor 400 set to convey the recording paper 154 at an ideal speed, and the motor required to convey the recording paper 154 from the (n)th check point to the (n+1)th check point. If the number of 400 steps is S(n+1), then S(n+1) steps may be consumed within the time tr as follows: tr=ti(n+1)-tm(n)...(1). Therefore, the period T _Aj of the motor 400 from the (n)th check point to the (n+1)th check point is T _Aj =ti(n+1)-tm(n)/S(n+1)...(
2). Here, the time required for the motor 400 to be driven in S(n+1) steps in period T is ti(n+1)-ti(n), so ti(n+1)-ti(n)=T×S(n+1) ……(3
), and by substituting this into equation (2), the drive period T _Aj of the motor 400 in the next section is given by T _Aj =ti(n+1)-tm(n)/ti(n+1).

A flowchart of the above operation is shown in FIG. 11, and a block diagram is shown in FIG. 12.

As a result of the above implementation, the color misregistration, which previously had a distribution as shown in FIG. 13, has been improved as shown in FIG. 14.

In both figures, the vertical axis is the number of copies, and the horizontal axis is the amount of color shift based on yellow.
In the conventional version shown in Figure 2, there was a large color shift and the copy quality was uneven, whereas in the product of the present invention, as shown in Figure 13, there was a small color shift. It can be seen that there are many deviations and the copy quality is constant.

Effects of the invention According to the invention, the detection means for detecting the amount of movement of the recording paper 154 is connected to the ink donor film 5.
By arranging the ink donor film 51 and the recording paper 154 in an overlapping state between the peeling part between the ink donor film 51 and the recording paper 154 and the thermal head part, the recording paper 154 is detected by the detection means. The amount of movement of the ink donor film 5 is detected.
1 can be carried out in close contact with
Recording paper 154 before being fed to the thermal head section
Even if the paper has curls or wrinkles, this recording paper 1
Reference numeral 54 indicates that the ink donor film 51 is stretched tightly by tension, and the thermal head portion smoothes out the curls and wrinkles of the ink donor film 51, and the detection means detects the movement of the recording paper 154 as the amount of movement that is completely the same as that of the ink donor film 51. The amount can be detected accurately. Further, according to the present invention, since the recording paper detection means is integrated with the ink donor film and has tension on both sides of the recording paper in the running direction, the detection means only needs to contact a part of the recording paper in the width direction. As a result, the detection means can be made smaller, and the inertial mass of the detection unit is reduced due to the smaller size, thereby improving detection errors. Therefore, by using the transfer type thermal recording device according to the present invention, when performing color recording by overlapping colors such as yellow, magenta, sepia, and black, it is possible to obtain high-quality recording without color shift. .

[Brief explanation of drawings]

1 to 14 show an embodiment of the present invention. FIG. 1 is an explanatory diagram of the overall configuration, FIG. 2 is an enlarged explanatory diagram of the main part, and FIG. 3 is a section A of FIG. 1. FIG. 4 is an exploded perspective view showing the cassette section that supports the ink donor film, FIG. 5 is a block diagram showing the image signal forming device, and FIG. 6 shows the data transferred to each recording section. A block diagram showing the flow,
Fig. 7 is a perspective view showing the detection roller section, Figs. 8 and 9 are explanatory diagrams of how the pinch roller approaches and separates from the detection roller, and Fig. 10 shows a method of adjusting the speed of the motor that drives the drive roll. Diagrams for explanation: FIG. 11 is a flowchart, FIG. 12 is a block diagram, FIGS. 13 and 14 are diagrams showing the state of color misregistration, and FIG. 15 is a configuration explanatory diagram showing a conventional example. . 51 is an ink donor film, 152 is a thermal head, 154 is a recording paper, 301 is a detection roller, and 302 is a pinch roller.

Claims (1)

[Scope of claims for utility model registration] (1) Thermal head 152 and recording paper 15
3, a back roll 153 that presses the ink donor film 51 between them, an ink donor film drive means that drives the ink donor film 51, a detection roller 301 that is connected to a movement amount detection means such as an encoder, and a pinch roller that presses against this. 302 and these two rollers 30
When the recording paper 153 passes between 1 and 302 and the detection roller 301 rotates, the recording paper 1
53, and a control means for controlling the ink donor film drive means in accordance with the output of the detection means. A transfer-type thermal recording device characterized in that an ink donor film 51 and a recording paper 154 are arranged so as to be sandwiched in an overlapping state between a separation part from the recording paper 154 and a thermal head part. (2) Place the detection roller 301 of the detection means on the recording paper 1.
54. The transfer type thermal recording device according to claim 1 of the claimed utility model registration. (3) The transfer type thermal recording device according to claim 1 of the utility model registration claim, characterized in that the detection roller 301 constituting the detection means is made of metal and has minute protrusions on its outer peripheral surface. .