JPH06278297A - Printer - Google Patents

Abstract

PURPOSE:To provide a printer not damaging an ink ribbon, capable of preventing the wastefullness of the ribbon and the lowering of printing quality, eliminating inconvenience such that printing operation is interrupted for a long time and having simple constitution. CONSTITUTION:At each time when the printing to recording paper P of one page is completed, a platen roller 22 and rolls 27, 28 are reversely rotated to return an ink ribbon 24 to the supply roll 27. As a result, the lowering of printing image quality can be prevented without damaging the ink ribbon 24 and printing can be efficiently performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer type printing apparatus in which an ink on an ink ribbon is melted by a thermal head and is thermally transferred onto a sheet.

[0002]

2. Description of the Related Art In a thermal transfer type printing apparatus, a thermal head is arranged opposite to a platen roller. The ink ribbon wound around the supply roll passes between the heat sensitive head and the recording paper on the platen roller and is wound up by the take-up roll. Ink is transferred to the recording paper.

Currently, there are two types of ink ribbons, one-time ink ribbons and multi-pass ink ribbons. The former one-time ink ribbon has a high printing quality, but the printing frequency is usually once. Further, the latter multi-pass ink ribbon is slightly inferior to the former one-time ink ribbon in printing image quality, but since it can be printed a plurality of times, it is economically advantageous over the one-time ink ribbon. . The user properly uses both ribbons according to the print image quality required at that time and the number of prints.

When the entire multi-pass ink ribbon has been wound up from the supply roll to the winding roll, reversing the mounting position of each roll makes it possible to continue printing on the recording paper. . That is, the roll that was the supply roll at the time of the previous printing becomes the take-up roll, and the roll that was the take-up roll becomes the supply roll. For example, when using a multi-pass ink ribbon capable of printing twice, this roll reversal work is performed once, and when using a multi-pass ink ribbon capable of printing three times. The roll reversal work will be performed twice.

However, in this case, each time the winding of the multi-pass ink ribbon is completed, the user or the like has to remove each roll from the apparatus case and reverse the mounting position thereof, which is very troublesome. There was a problem that was.

Therefore, in recent years, there has been proposed a printing apparatus provided with an automatic winding mechanism that reverses the supply roll to automatically wind the ink ribbon on the winding roll onto the supply roll.

[0007]

However, in general,
Since the thermal head is pressed against the platen roller,
The ink ribbon is strongly pressed between the platen roller and the thermal head. Therefore, in the automatic winding mechanism described above,
When the rewinding of the ink ribbon from the take-up roll to the supply roll is performed continuously and completely, the ribbon is often caught by the thermal head or the like in the rewinding process.

Once the catch is generated, rewinding is continued in that state, causing fatal damage to the ribbon. In this case, the print image quality is deteriorated, and the next print may be hindered. In addition, the total length of an ink ribbon is usually several tens of meters even if it is short. Since it takes a long time to continuously wind up such a length, it is inconvenient because the printing operation becomes impossible during that time.

In order to prevent this, a structure has been proposed in which, when the ink ribbon is rewound, the thermal head is separated from the platen roller to release the pinching force acting on the ink ribbon. However, in this configuration, a means for separating the thermal head from the platen is required, which complicates the configuration. Moreover, even with this configuration, the above inconvenience is still unsolved when the ink ribbon is continuously rewound.

In addition, in this structure, the synchronous relationship between the platen roller and the ink ribbon is broken by releasing the clamping pressure. Therefore, the rewinding speed of the ink ribbon changes as the winding diameter of the ink ribbon wound around the supply roll changes. Therefore, it becomes impossible to rewind the ink ribbon by a certain amount after each page of printing is completed, and the ink ribbon has a part which is used insufficiently or a part which is used excessively. Print quality is degraded.

The present invention has been made in order to solve the above problems, and its purpose is to prevent damage to the ink ribbon, prevent waste of the ribbon and deterioration of print quality, and prolong the printing operation. An object of the present invention is to provide a printing device which can eliminate the inconvenience of time interruption and which has a simple structure.

[0012]

In order to achieve the above object, in the present invention, a thermal transfer type ink ribbon is sandwiched between a recording sheet and a thermal head, and the ink is transferred to the recording sheet. In the printing apparatus, a ribbon returning means for returning the ink ribbon to its supply side each time printing is performed within a predetermined range, and a ribbon returning amount for one time is set to be shorter than the range. The gist is to have a setting means.

[0013]

According to the above construction, every time printing of a predetermined range, for example, printing of one sheet of paper is completed, the ink ribbon is returned to the supply side by a length shorter than the length spent for the printing. Be done. In this case, since the returning amount of the ink ribbon is small, the chance of being caught by the thermal head or the like is small and the returning time is short. Further, since the ink ribbon return time is short, it is not necessary to separate the thermal head from the platen roller.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a facsimile machine will be described below with reference to the drawings.

First, the structure of the facsimile apparatus of this embodiment will be described. As shown in FIG. 1, a reading unit 2 for reading an image on a document G is arranged in the device case 1. In the device case 1, a recording unit 3 for printing on the recording paper P based on the received image data and the like.
Are arranged. Paper cassettes 4a and 4b for respectively accommodating recording sheets P of different sizes are detachably attached to the lower part of the device case 1. The upper paper cassette 4a has B5 size (width: 182 mm
× vertical: 257 mm) recording paper P, and A4 size (horizontal: 210 mm × vertical: 2) in the lower paper cassette 4b.
(97 mm) recording sheets P are accommodated in a stacked state.

A document tray 6 on which documents G are stacked and supported is arranged on the upper part of the apparatus case 1, and a feed assist roller 7 is provided.
By the rotation of, the feeding force is applied to the document G. A separation roller 8 and a separation pad 9 for feeding the originals G one by one are provided in the apparatus case 1. On the downstream side of the separation roller 8, a transfer path 10a through which the document G passes is formed by a pair of guide plates 10. A reading window 11 is formed on one of the guide plates 10.

The reflected light emitted from the light source 12 to the original G through the reading window 11 passes through the reading window 11 again,
The image sensor 15 is finally irradiated with light through the plurality of mirrors 13 and the lenses 14, and the image of the document G is read. Further, the plurality of feed rollers 17 discharge the document G after image reading from the document discharge port 16.

Above the paper cassettes 4a and 4b, half-moon shaped paper feed rollers 18 are installed so as to be positively rotatable. Then, by the rotation of the paper feed roller 18, the recording papers P are delivered one by one from the paper cassettes 4a and 4b through the guide plate 19 toward the recording unit 3. Further, due to the rotational force of the feed roller 20, the feed force is further applied to the recording paper P delivered from the paper cassettes 4a and 4b.

The recording unit 3 is composed of a platen roller 22, a thermal head 23 disposed in contact with the platen roller 22, and the like. A multi-pass ink ribbon (hereinafter, simply referred to as an ink ribbon) 24 accommodated in the ribbon accommodating cassette 21 shown in FIG. 2 is sandwiched between the platen roller 22 and the thermal head 23. The platen roller 22 is positively rotated by a platen motor Pm described later. In addition, the platen roller 22
A rotary encoder 61 is connected to the rotary encoder 61. The rotary encoder 61 detects the rotation amount of the platen roller 22 and generates a pulse corresponding to the feed amount of the ink ribbon 24.

As shown in FIG. 2, a supply roll 27 and a winding roll 28 are rotatably supported on the frame 21a of the ribbon accommodating cassette 21 via shafts 30 and 31, respectively. The gears 35, 3 are attached to the shafts 30, 31 on one side.
6 is formed. These gears 35, 36 are gears (not shown) connected to a roll motor Rm described later.
Are meshed.

A guide plate 46 is provided on the upstream side of the platen roller 22. Further, on the upstream side of the guide plate 46, a pair of supply rollers 47 for supply is rotatably supported. On the other hand, on the downstream side of the platen roller 22, a pair of ejection feed rollers 48 are rotatably supported. Further, a recording paper discharge tray 49 is arranged on the downstream side. A pair of guide plates 50 are provided between the feed roller 47 and the platen roller 22.
Is provided.

Therefore, the recording paper P delivered from the paper cassettes 4a, 4b is supplied to the recording section 3 through the recording paper feed passage formed between the guide plates 46, 50. Then, as the platen roller 22 rotates,
The recording paper P and the ink ribbon 24 are sent while being sandwiched between the platen roller 22 and the thermal head 23. At this time, the ink ribbon 24 based on the operation of the thermal head 23
Desired data, received image information, and the like are printed on the recording paper P by melting the above ink. The printed recording paper P is ejected to the recording paper ejection tray 49 by the rotational force of the ejection feed roller 48.

In the power transmission mechanism of the roll motor Rm, the paper feed speed by the platen roller 22 and the moving speed of the ink ribbon 24 wound around the take-up roll 28 are always the same during the printing operation. Therefore, a speed adjusting mechanism is provided.

Each time the recording of one page of the recording paper P is completed, the ink ribbon 24 is returned to the supply roll 27 side by a predetermined amount and wound on the roll 27. The amount by which the ink ribbon 24 is returned is shorter than the length corresponding to the range of one page, and details thereof will be described later.

Next, the electrical construction of the facsimile will be described with reference to the block diagram of FIG. The controller C is a central processing unit (CPU) 55, a read-only memory (ROM) 56 that stores each control program in advance, and a readable and writable memory (RAM) that temporarily stores received image information and various data. 57 and 57.

A network control unit (NCU) 58 and a modem 59 are provided on the input side of the CPU 55.
Are connected. The NCU 58 connects / disconnects a telephone line based on a control signal from the CPU 55, and
The modem 59 performs modulation and demodulation of transmitted / received data.

Further, the input side of the CPU 55 is connected to the key input section 60 of the operation panel provided on the upper surface of the reading section 2 and the apparatus case 1. This key input section 60
Is provided with a key for setting the printable number N of the ink ribbon 24 and a key for selecting various modes. Further, the rotary encoder 61 described above is connected to the input side of the CPU 55.

On the other hand, the recording unit 3, the platen motor Pm, and the roll motor Rm are connected to the output side of the CPU 55. The CPU 55 controls the recording unit 3, each motor P based on the control program stored in the ROM 56.
Drive control of m, Rm, etc.

When the CPU 55 receives the image information,
After temporarily storing it in the RAM 57, the size of the recording paper P on which the image information is to be printed is selected. Also, CP
After selecting one page of recording paper P, U55 calculates the ink ribbon return amount R. Then, according to the calculation result, the CPU 55 reversely rotates the platen motor Pm and the roll motor Rm.

The ink ribbon return amount R calculated by the CPU 55 will be described in detail. The CPU 55 prints the number of printable times N of the ink ribbon 24 input by the key input unit 60, the feed direction dimension of the recording paper P selected at that time, and the vertical dimension of the recording paper P in this embodiment (B5 size is 2
57 mm, A4 size is 297 mm), and the ink ribbon return amount R is calculated. And the formula is
Ink ribbon return amount R = vertical dimension of recording paper P × (printable number of times N−1) / printable number of times N. The data of this calculation formula is stored in the ROM 56.

In this embodiment, the controller C, the platen motor Pm, the roll motor Rm, etc. constitute a ribbon returning means for returning the ink ribbon 24 to its supply side. Further, in this embodiment, the CPU 55 and the ROM
56 and the like constitute setting means for setting the ribbon return amount R once to be shorter than the above range.

Next, the operation of the facsimile apparatus configured as described above will be described. 4 and 5 are flowcharts showing a control processing routine executed by the CPU 55. This flow chart proceeds under the control of the CPU 55 based on the program stored in the ROM 56.

When the processing shifts to this routine, first,
In step 101, the CPU 55 causes the key input unit 60 to
From the input of the printable number N of the ink ribbon 24. In step 102, the reception of image information is awaited, and if the image information is received here, step 10
3, the received image information is stored and held in the RAM 57.

In step 104, the CPU 55 determines whether or not the storage of all the received image information is completed, and when it is determined that the storage is completed, the process proceeds to step 105.
In step 105, the CPU 55 selects the size of the recording paper P to be printed based on the paper size information in the received image information. In the following step 106, the ink ribbon return amount R is calculated from the above-described formula in accordance with the selected paper size. Then, in step 107, the CPU 55 drives the recording unit 3, the motors Pm, Rm, etc. to start printing the received image information.

In step 108, the CPU 55 determines whether or not the printing on one recording sheet P is completed in step 105 and the recording sheet P is discharged from the recording section 3. The ejection of the recording paper P is detected by a sensor (not shown) arranged on the downstream side of the platen roller 22. If it is determined that the printing is completed and the recording paper is ejected, the CPU 55 proceeds to the next step 109 to stop the driving of the recording unit 3 to temporarily stop the printing operation. In the next step 110, the platen motor Pm and the roll motor Rm are reversely rotated to perform the returning operation of the ink ribbon 24.

In step 111, the CPU 55 determines whether or not the count value of the pulse generated from the rotary encoder 61 has reached the count value corresponding to the ink ribbon return amount R calculated in step 106. That is, it is determined whether or not the ink ribbon 24 has been returned by the ink ribbon return amount R. If it is determined that the pulse count value generated from the rotary encoder 61 has reached the pulse count value corresponding to the ink ribbon return amount R, the process proceeds to step 112.

In step 112, the CPU 55 stops the driving of the roll motor Rm and the platen motor Pm, and stops the rewinding of the ink ribbon 24. on the other hand,
When the CPU 55 determines in step 112 that the count value of the pulse generated from the platen motor Pm has not yet reached the value corresponding to the ink ribbon return amount R, the pulse count value becomes the corresponding value. The drive of each motor Pm, Rm is continued until it reaches.

In step 113, the CPU 55 causes the R
If it is determined that the received image information is still stored in the AM 57, and if it is determined that the received image information is still stored in the RAM 57, the process jumps to step 105 and the subsequent processes are repeated.

Here, a specific example in which the printable number N of the ink ribbon 24 is 3 and the size of the recording paper P is A4 will be described. As described above, the ink ribbon return amount R is equal to the ink ribbon 2
It is calculated based on the printable number N of 4 and the vertical dimension of the recording paper P selected at that time. And the formula is
Since “ink ribbon return amount R = vertical dimension of recording paper P × (printable number of times N−1) / printable number of times N”, substituting each value into the above formula yields “297 mm × (3-1)”
÷ 3 ”.

Therefore, the amount R of return of the ink ribbon at one time is "198 mm". In this case, when the printing of the first sheet is completed, the ink ribbon 24 is returned to the supply roll 27 side by "198 mm". That is, the ink ribbon 24
Is rewound on the supply roll 27 by an amount corresponding to a distance of two-thirds of the vertical size of A4 size.

That is, on the first recording sheet P, the ink ribbon 24 moves in the direction of the arrow together with the recording sheet P as shown in FIG.
Printing is performed using three areas (the vertical dimension per area is 99 mm). Then, after the printing on one recording sheet P is completed, the rolls 27 and 28 and the platen roller 22 are reversely rotated and the ink ribbon 24 is returned by "198 mm" in the opposite arrow direction, and then the second recording sheet P Printing on P is started.

Therefore, as shown in FIG. 7, the use area of the ink ribbon 24 when printing on the second recording paper P is
It becomes the area used in the previous printing, the area, and the new area. Therefore, when printing is performed on the second recording paper P, the area and the number of times of printing of the area are twice. Then, after the printing on the second recording paper P is completed, the ink ribbon 24 is returned by "198 mm", and the printing on the third recording paper P is started.

Therefore, as shown in FIG. 8, the use area of the ink ribbon 24 when printing on the third recording paper P is
It becomes the area used in the previous printing, the area, and the new area. Therefore, when printing is performed on the third recording sheet P, the number of times of printing in the area is three, and the number of times in the area is two. Then, after the printing on the third recording paper P is completed, the ink ribbon 24 is returned by "198 mm", and
Printing on the first recording sheet P is started. Further, in the printing of the fourth sheet, as shown in FIG. 9, printing is performed using the areas 1 to 3, and the number of times the area is used is 3 times.

As described above, each region of the ink ribbon which has been used three times is sequentially used three times in a repeated manner. In the case of an ink ribbon which has been used four times for printing, the value of “N” is 4, so that the ink ribbon 2 for one recording sheet is
The four used areas are divided into four, and these areas are sequentially used four times in a duplicated manner.

When the selected recording paper P is B5 size, the size (vertical size) of the recording paper P in the feeding direction is changed, and each area becomes a size that divides the B5 size equally. The other operations are the same as described above.

Therefore, in the facsimile apparatus according to the present embodiment, the ink ribbons 24 can be successively used from the starting end side, and the ink ribbons 24 can be effectively used for the number of printable times. Further, in the facsimile apparatus of this embodiment,
Each time the printing of the range of one recording sheet P is completed, the platen roller 22 and the supply roll 27 are rotated in the reverse direction so that the ink ribbon 24 is returned within a range shorter than the range.

As a result, each ink ribbon 24
The amount to be returned is reduced. Therefore, there is almost no possibility that the ink ribbon 24 will be caught by the thermal head 23, and even if the ink ribbon 24 is caught, the movement of the ink ribbon 24 is reversed in printing on the next page, and the catch is eliminated. To be done. Therefore, it is possible to prevent a situation in which the print quality is deteriorated due to damage of the ink ribbon 24 and the ink ribbon 24 cannot be used. In addition, since damage to the ink ribbon can be prevented as described above, there is no need to separate the thermal head 23 from the platen roller 22 in order to release the clamping pressure on the ink ribbon 24. Therefore, the structure does not become complicated.

In addition, in this embodiment, since the amount of one ribbon return is short, the time required for the return is extremely short, and it takes a long time to return the ribbon, during which printing operation becomes impossible. Printing can be performed efficiently.

Further, in this embodiment, the ink ribbon 24
The ink ribbon 24 is pinched between the platen roller 22 and the thermal head 23 also when the ink is returned. Therefore, the platen roller 22 and the ink ribbon 24 are driven at the same speed, and the ink ribbon 2 is moved based on the rotation amount of the platen roller 22.
A return amount of 4 can be detected. Therefore, even if the outer diameter of the ink ribbon 24 wound around the supply roll 27 changes and the return speed of the ink ribbon 24 changes, the ink ribbon 24 can be reliably returned by the set amount. as a result,
It is possible to surely use each area of the ink ribbon 24 a predetermined number of times and not to use the area more than a predetermined number of times.
It is possible to prevent deterioration of print quality and prevent waste of the ink ribbon 24.

The present invention is not limited to the above embodiments, but can be embodied in the following modes without departing from the spirit of the invention. (1) Embodying the present invention in an ordinary printer.

(2) In the above-described embodiment, the ink ribbon 24 is returned by the amount corresponding to the ink ribbon return amount R each time printing in the range of one page is completed, but less than one page such as half of one page. Alternatively, the ink ribbon 24 may be returned every time printing of a range of a plurality of pages is completed. In this case, the length in the feeding direction of less than one page or a plurality of pages may be divided into the printable number N of the ink ribbons 24, and the ink ribbon 24 may be returned by the printable number N-1. .

(3) In the above embodiment, the ink ribbon is embodied in the paper feed direction together with the recording paper, but the present invention is embodied in the ink ribbon 24 in the print line direction. Good. In this case, each time printing of one print line is completed, the ink ribbon 24 is returned in the print line direction (direction orthogonal to the recording paper feed direction) by the range of the printable number N-1.

(4) The ink ribbon return amount R for one time is set to a value other than the printable number N-1, for example, the printable number N-1.2. In this case, there are some portions on the ink ribbon 24 that do not reach the printable number N, but since the portions are small, there is almost no problem.

[0054]

As described in detail above, according to the present invention,
Since the ink ribbon can be returned to the supply side without damaging it, it is possible to prevent deterioration of the print image quality, moreover, it is possible to perform printing efficiently, and it is also excellent in that the configuration is simple. Produce an effect.

[Brief description of drawings]

FIG. 1 is a sectional view of a facsimile apparatus according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a ribbon cassette, an ink ribbon, and the like.

FIG. 3 is a block diagram showing an electrical configuration of a facsimile device.

FIG. 4 is a flowchart showing the operation of the CPU.

FIG. 5 is a flowchart showing the operation of the same CPU.

FIG. 6 is a schematic plan view of the recording paper and the ink ribbon when printing is performed on the first recording paper (A4 size) using the ink ribbon that can be printed three times.

FIG. 7 is a schematic plan view of the recording paper and the ink ribbon when printing is performed on the second recording paper (A4 size) using the ink ribbon that can be printed three times.

FIG. 8 is a schematic plan view of the recording paper and the ink ribbon when printing is performed on the third recording paper (A4 size) using the ink ribbon that can be printed three times.

FIG. 9 is a schematic plan view of the recording paper and the ink ribbon when printing is performed on the fourth recording paper (A4 size) using the ink ribbon that can be printed three times.

[Explanation of symbols]

P ... Recording paper, 24 ... Ink ribbon (multi-pass ink ribbon), C ... Controller that constitutes ribbon returning means and setting means, Pm ... Platen motor that constitutes ribbon returning means, Rm ... Roll that constitutes ribbon returning means For motor

Claims (1)

[Claims] 1. A printing apparatus in which a thermal transfer type ink ribbon is sandwiched between a recording paper and a thermal head, and the ink is transferred to the recording paper, every time printing is performed within a predetermined range. A printing apparatus provided with a ribbon returning means for returning the ink ribbon to its supply side and a setting means for setting the ribbon returning amount for one time to be shorter than the above range.