JP2003127476A - Line thermal printer and its adjusting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To sustain a high accuracy of print recording at the time of superposed print recording on a single print recording medium using two print recording heads of one line thermal printer. SOLUTION: The number of driving steps of a sheet feed motor 40 is made variable and test print lines L1-L10 are print recorded appropriately on a print recording medium 50 by means of a direct thermal head 14 and a thermal transfer head 16. Print recording state of the test print lines L1-L10 is then discriminated and the number of driving steps of the sheet feed motor 40 is selected when the test print lines L1-L10 by respective heads 14 and 16 coincide with each other. Sheet feed amount of the print recording medium 50 is set for respective heads 14 and 16 by the number of driving steps thus selected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line thermal printer and a method for adjusting the line thermal printer, and more particularly to a so-called combination printer for coloring a thermal paper for thermal printing and thermally transferring the ink of an ink ribbon onto the thermal paper. And a method of adjusting the same.

[0002]

2. Description of the Related Art As a type of line thermal printer,
The Applicant has one platen roller and a first thermal head which is arranged on the downstream side in the transport direction of the roll-shaped thermal paper, and which is press-contactable to the platen roller, and further downstream in the transport direction of the thermal paper. , A so-called combination printer having a second thermal head capable of being pressed against the platen roller is proposed.

Then, the thermal paper fed from the paper accommodating section for accommodating the thermal paper to the platen roller side is first subjected to thermal printing by the first thermal head which is heated, for example, to make characters and the like color black. Next, the thermal paper fed to the downstream side is subjected to thermal transfer of the ink of the ink ribbon, for example, the melted ink so as to become red, by the heated second thermal head, so that the same thermal paper is colored in two colors. It is designed to be printed and recorded.

Consider an example of the print record data shown in FIG. First, as shown in FIG. 7, the A-character portion 121 is colored in black on the thermal paper by the heated first thermal head to print and record. Then, while the thermal paper is conveyed in the direction of the arrow in the figure, the background portion 122 shown in FIG. 8 is thermally transferred with the ink of the ink ribbon in red by the second thermal head that has been heated to perform print recording. At this time, the platen roller is rotated and the paper is fed so as to print and record the same on the same portion of the thermal paper.

[0005]

By the way, when printing and recording with a line thermal printer having the first thermal head and the second thermal head (heat-sensitive head, thermal transfer head) as described above, these two heads are mounted. Due to the variation of the position, when the print recording is performed by superposing it on one thermal paper, there is a fear that the print shift may occur as shown in FIG. For this reason, for example, in a supermarket or the like, if the amount of money and the coupon ticket displaying the product are overlaid and printed on one receipt sheet, the appearance is not good.

An object of the present invention is to provide at least two thermal heads for heat-sensitive use and thermal transfer, and to accurately maintain the print-recording when the print-recording is carried out at the same position of one print-recording medium by these heads. And a method of adjusting the same.

[0007]

Means for Solving the Problems As a means for solving the above problems, a platen roller provided with a rotary shaft and rotatable about the rotary shaft, and at a predetermined interval near the outer peripheral surface of the platen roller. At least two heads of a first thermal head and a second thermal head that are arranged to face each other, a paper feed motor that rotationally drives the rotation axis of the platen roller, and an outer peripheral surface of the platen roller and each head that can be pressed against the outer peripheral surface. And a print recording medium that can be conveyed between the print head and the ink ribbon cassette having an ink ribbon containing ink. The print head has the first thermal head pressed against the outer peripheral surface of the platen roller and interposed therebetween. Heat-sensitive printing, and the print recording medium having the heat-sensitive printing is fed between the outer peripheral surface of the platen roller and the second thermal head, A line thermal printer in which a thermal head is pressed against the outer peripheral surface of a platen roller to thermally transfer the ink of an ink ribbon cassette to a predetermined location on the print recording medium where the thermal printing has been performed, and the print recording is performed by superposing the paper feeding motor. The number is varied so that the print locations on the print recording medium in the first thermal head and the second thermal head are the same.

As a second solving means, a differential value from the reference drive step number of the paper feed motor is obtained, and the differential value is stored in the storage means, and when the print recording medium is fed, The difference value read from the storage means is added to the reference drive step number to drive the paper feed motor.

As a third solving means, the number of driving steps of the paper feed motor is varied so that each head of the first thermal head and the second thermal head appropriately prints and records a print line on a print recording medium. The print recording state of the print line is identified, and the number of drive steps of the paper feed motor when the print lines of each head match is selected, and the paper feed of the print recording medium to each head is performed by this selected number of drive steps. The amount is set.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A line thermal printer which is an embodiment of the present invention, a so-called combination printer, will be described below with reference to FIGS. As shown in FIG. 1 and FIG. 2, the combination printer 10 has one platen roller 11 substantially in the upper center thereof, and is wound on the right side of the platen roller 11 in the drawing in a roll shape. The thermal paper (print recording medium) 8 capable of developing only one color is detachably stored. The platen roller 11 has a metal rotating shaft 11a at the center and an outer peripheral surface 11c made of an elastic material such as rubber on the outer periphery thereof. A first thermal head 14 for direct thermal is arranged near the outer peripheral surface 11c of the platen roller 11, which is a part of the transport path of the thermal paper 8. A plurality of heat generating elements 14 a (see FIG. 4) are formed on the first thermal head 14 so as to be aligned in the width direction of the thermal paper 8.

As shown in FIG. 2, the first thermal head 1
4 is a head mount 14b and this head mount 14b
A biasing member (not shown) for constantly pressing the head substrate 14c on which the plurality of heat generating elements 14a (see FIG. 4) are aligned and the outer peripheral surface 11c of the platen roller 11 with elasticity. And have. Head mount 14b
Is provided with a rotatable small roller 14d at one end on the side where the thermal paper 8 is fed. In addition, this head mount 14b
Is attached to a printer device main body (not shown). The first thermal head 14 is constantly in pressure contact with the platen roller 11 via the thermal paper 8.

Next, the outer peripheral surface 1 of the platen roller 11
Around the 1c, a second thermal head 16 having a predetermined distance H (see FIG. 4) from the first thermal head 14 is arranged close to the first thermal head 14. That is, the first thermal head 14 which is a direct thermal head and the second thermal head 1 which is for thermal transfer.
6 are arranged in the vicinity of the outer peripheral surface 11c of the platen roller 11 so as to face each other at a predetermined interval.

The second thermal head 16 is a rotary arm 16b which is a head mount, and a head substrate 16c fixed to the rotary arm 16b and having a plurality of heating elements 16a (see FIG. 4) arranged in line. The outer peripheral surface 11c of the platen roller 11 has an urging member (not shown) which has elasticity and is pressed against the outer peripheral surface 11c.

The rotating arm 16b includes a head substrate 16c.
The first ribbon feeding roller 16d and the second ribbon feeding roller
A ribbon feed roller 16e is provided, and a rotary shaft 16f is provided at one end of the rotary arm 16b. The rotary arm 16b rotates in the clockwise direction with the rotary shaft 16f as a fulcrum (arrow B in FIG. 2). Direction). The second thermal head 16 is adapted to come into pressure contact with the platen roller 11 with the thermal paper 8 and an ink ribbon described later interposed therebetween.

A rotatable pressure contact roller 18 is provided near the outer peripheral surface 11c of the platen roller 11, which is the most downstream side of the thermal paper 8 conveyance path.
8 is brought into pressure contact with the outer peripheral surface 11c, and the thermal paper 8 sandwiched between the platen roller 11 and the pressure contact roller 18 is fed in the direction of arrow A in FIGS.

Next, as shown in FIGS. 1 and 2, the ribbon cassette 20 includes a delivery core 20a and a winding core 20.
b, and both ends of the cores 20a and 20b are wound, and an ink ribbon 20c is formed by applying different colors of ink in a gradual manner. And ribbon cassette 2
0 is attachable to and detachable from the apparatus body of the combination printer 10. When mounted in the main body of the apparatus, a part of the exposed ink ribbon 20c comes into sliding contact with the head substrate 16c of the second thermal head 16.

FIG. 3 shows a combination printer 10.
Part of the block diagram of the print recording mechanism of FIG. The head substrate 14c in which a plurality of heating elements 14a are aligned in the sub-scanning direction is always in elastic contact with the platen roller 11 rotatable about the rotation shaft 11a. Also, the head substrate 1
A driver 25 for heating and driving the heating element 14a is electrically connected to 4c.

The driver 25 includes a head controller 27.
Are electrically connected, and the head controller 27
A command is issued to the driver 25 so as to selectively control the energization of each heating element 14a.

At this time, the head controller 27 determines the number of divisions of the heating elements 14a according to the print recording data, allocates the number of blocks of the heating elements 14a according to the number of divisions, and the heating elements 14a of each number of blocks. In order to sequentially energize the groups, a command (request) for division driving is output to the driver 18.

The thermal paper 8 is sandwiched between the first thermal head 14 and the platen roller 11, and the thermal printing is performed (direct thermal) based on the heating element 14a of the first thermal head 14 which is selectively heated. It will be printed and recorded at.

As with the first thermal head 14, the second thermal head 16 also has a plurality of heating elements 16a aligned in the sub-scanning direction, and the first thermal head 1
As in the case of No. 4, a driver and a head controller (not shown) thermally transfer to the thermal paper 8 with the ink of the ink ribbon described later by the heating element 16a that is selectively heated according to the print recording data.

Next, the rotary shaft 11a of the platen roller 11
A paper feed motor 40, such as a stepping motor, is connected to and provided with. The paper feed motor 40 rotationally drives the platen roller 11 via a plurality of gear groups (not shown) according to the number of drive steps (drive pulse) input for each print line. A motor control unit 42 as a control unit is electrically connected to the paper feed motor 40. The motor control unit 42 drives the platen roller 11 to rotate accurately with the number of drive steps applied. ing.

The motor control unit 42 includes a division number counter 3
0 is electrically connected, and this division number counter 30
When a command for division drive having a smaller number of divisions than the predetermined number of divisions is output from the head controller 27 or the like, is the print recording data after the predetermined number of divisions and the instruction. The number of divisions of the print line is counted. Then, the division number counter 30 outputs the data of the counted division number.

The motor control unit 42 has a speed adjusting unit 44 built therein. The speed adjusting unit 44 is a memory such as a flash memory or a R such as a one-time program.
A storage unit 50 such as an IC chip made of an OM can be connected, and the number of drive steps of the paper feed motor 40 stored in the memory or the IC chip is read to rotate the paper feed motor 40 at a desired speed. It is driven and operates at a predetermined paper feed amount.

Next, the operation of printing and recording by the combination printer 10 thus constructed will be briefly described. As shown in FIGS. 1 and 2, the thermal paper 8 wound in a roll shape is One end side 8a is pulled out,
The platen roller 11 and the first and second thermal heads 14,
It is guided through the transport path between the platen roller 11 and the pressure contact roller 18 and the platen roller 11 and the pressure contact roller 18. This one end side 8
When the platen roller 11 is rotationally driven, a is a pressure contact roller 1 that is in pressure contact with the outer peripheral surface 11c of the platen roller 11.
By rotation with 8, the paper is fed in the direction of arrow M in FIG.
The print recording start position 8s within the print recording range 8c of the thermal paper 8 is the head substrate 14c of the first thermal head 14.
Heating element 1 which is selectively heated when placed opposite to
By 4a, the color is developed by thermal printing for each printing line sequentially from the starting position 8s.

Then, the thermal paper 8 on which the thermal printing has been carried out is fed at a predetermined rotation speed of the platen roller 11, and when it comes to a position facing the head substrate 16c of the second thermal head 16, the second thermal head 16 Rotates about the rotary shaft 16f as a fulcrum in the clockwise direction in FIG. 2 and makes elastic contact with the outer peripheral surface 11c of the platen roller 11. At this time, the winding core 20b of the ribbon cassette 20 is wound in advance to position the ink of a desired color at a predetermined position, and the ink of the ink ribbon 20c is melted by the selectively heated heating element 16a. Then, the print recording start position 8 of the thermal paper 8
The thermal transfer printing is sequentially performed for each print line from s, and the print recording is performed by superimposing it on a predetermined print position. When performing thermal recording on the thermal paper 8, the second thermal head 16 is rotated counterclockwise about the rotation shaft 16f as a fulcrum so as to be separated from the platen roller 11. Thermal head 1
Print and record only with 4.

Next, the combination printer 10
A method of adjusting the number of drive steps of the paper feed motor 40 corresponding to the distance H between the first thermal head 14 and the second thermal head 16 will be described. First, in the assembly process of the combination printer 10, the platen roller 11, the first thermal head 1
4, the second thermal head 16, the paper feed motor 40, etc. are incorporated to complete the print recording mechanism.

Next, the test ribbon cassette 20 and the thermal paper 8 are attached to the combination printer 10 in which the printing and recording mechanism necessary for printing and recording is incorporated, and the printing test pattern is printed and recorded on the thermal paper 8. To do. This test pattern of the print line is used to accurately determine the print recording position on the thermal paper 8, and the paper feed motor 40 is driven to adjust the paper feed amount of the platen roller 11 to determine the optimum value. The number of steps is changed, and it is measured and performed.

As shown in FIG. 5, the combination printer 10 incorporating a print recording mechanism is incorporated into a shipping inspection jig (not shown), and the ribbon cassette 20 and the thermal paper 8 are mounted. The number of reference drive steps S0 which is predetermined in the design of the paper feed motor 40
Rotational driving is performed by increasing or decreasing the number of driving steps by several steps before and after the number of driving steps including (for example, rank 10). For example, the standard driving step number S0
When the paper feed motor 40 is rotationally driven by the rank 7, which has a smaller number of driving steps than the above, the print line L1 is moved to the second line by the first thermal head 14 on the thermal paper 8.
A print line L2 is printed and recorded by the thermal head 16, and an opening having a width W1 is generated between the print lines L1 and L2.

Next, when the thermal paper 8 is fed by the number of drive steps of the paper feed motor 40 which is slightly smaller than the reference drive step number S0 corresponding to rank 8, the first thermal head 14 causes the print line L3 to move to the first line. The print lines L4 are printed and recorded by the 2 thermal heads 16, respectively.
The width dimension W2 (<W1) has a slight difference. Next, the reference driving step number S corresponding to rank 9
When the thermal paper 8 is fed with the number of drive steps of the paper feed motor 40 slightly less than 0, the first thermal head 14
The print line L5 is printed by the second thermal head 16, and the print line L6 is printed by the second thermal head 16, and the width dimension W3 thereof is substantially zero.

Next, when the paper feed motor 40 is driven by the standard driving step number S0 corresponding to rank 10, and the platen roller 11 is rotated, the print line L7 is moved by the first thermal head 14 and the second thermal head 16 is moved. Thus, the print line L8 is printed and recorded on the thermal paper 8, and the print line L8 precedes the thermal paper 8 on the contrary to L7, and the width dimension W4 thereof is slightly opened. Subsequently, when the thermal paper 8 is fed by the number of driving steps of the paper feeding motor 40 corresponding to the rank 11 which is larger than the reference driving step S0, the print line L9 is moved by the first thermal head 14 and the thermal line 8 is moved by the second thermal head 16. The print lines L10 are printed and recorded on the thermal paper 8, respectively.
The width dimension W5 has an opening larger than the width dimension W4.

As described above, the paper feed motor 40 is sequentially driven to rotate by the number of drive steps including the predetermined reference drive step number S0 and variable before and after the reference drive step number S0, and the platen roller 11 is rotated so that the thermal paper 8 is formed. The first thermal head 14 performs heat-sensitive print recording, and the second thermal head 16 performs thermal transfer print recording.

After that, a plurality of print lines L1 and L2, L3 and L4, L5 and L6, L7 printed and recorded on the thermal paper 8 are provided.
And L8 and L9 and L10 are inspected for variations in width dimensions W1 to W5. The variation of the width dimensions W1 to W5 is automatically recognized by an image recognition device or the like, and the print line L5
Rank 9 that minimizes L6 and L6 is selected. It should be noted that, even if the image recognition device or the like is not automatically recognized, the operator may visually check the inspection, judge that the rank 9 is the best, and select it. In this way, the print recording mechanism of the combination printer 10 inspects the variations in the mounting dimensions between the heads 14 and 16 that occur for each model during the shipping inspection process, and corrects the positional deviation of the print recording.

Next, the number of drive steps that attains this rank (for example, rank 9) is recorded in the storage means 50 such as a flash memory or a ROM for a one-time program. In addition,
When a plurality of print recording mechanisms of the line thermal printer 10 are packaged and shipped, for example, for each lot, one recording unit 50 that stores the rank data for each printing mechanism for each shipped lot is provided. You can package it. In this case, the storage means 50 can be effectively used. Then, when the combination printer is finally assembled at the shipped partner, the storage means 50 is used.
The number of drive steps (rank 9) stored in is read out, and the paper feed motor 40
Is set to rotate. As described above, both the first thermal head 14 and the second thermal head 16 superimpose (compose) on the same portion of the thermal paper 8 to print and record.

When a large number of shipping lots of the print recording mechanism of the combination printer 10 are not available, a sticker indicating the rank may be simply attached instead of the storage means 50. In this case, the storage means 5
Even if you do not use 0, a sticker that displays the rank (for example,
A barcode may be attached and managed so that adjustment can be made for each unique mechanism of the printer 10.

Further, this rank may be a difference value from the standard driving step number of the paper feed motor 40. That is, assuming that the measured optimum driving step number Sn with respect to the reference driving step number S0, the difference value (S0-
Sn) is stored in the storage means 50 as storage data. By doing so, the amount of data stored in the storage means 50 can be small, so that an inexpensive storage means 50 can be used.

As described above, in the combination printer 10 of the present embodiment, the number of driving steps of the paper feed motor 40 is changed so that the first thermal head 14 and the second thermal head 16 print the test line on the thermal paper 8 for testing. Is appropriately printed and recorded, the print recording state of the test print line is identified, and when the test print lines Ln (n = 1, 2, 3 ...) By the thermal heads 14 and 16 match. Select the number of drive steps of the paper feed motor 40,
Each thermal head 1 with this selected number of drive steps
By setting the paper feed amount of the thermal paper 8 with respect to Nos. 4 and 16, the print misalignment of the print recording on the thermal paper 8 due to the variation of the positional accuracy due to the attachment of the two thermal heads 14 and 16 is determined by the paper feed motor 40. Since the paper feed amount is corrected before shipment, the user feeds the paper with the optimum number of drive steps of the paper feed motor 40 as described above, so that print misregistration at the time of print recording can be suppressed and superimposition can be performed with high accuracy. ) Printing can be performed.

Further, the reference drive step number S0 previously determined from the selected drive step number of the paper feed motor 40.
From the storage means 50, and when the thermal paper 8 is fed, the difference value read from the storage means 50 is used as the reference drive step number S0.
By driving the paper feed motor 40 in addition to the above, the paper feed amount of the platen roller 11 is determined, and the paper feed amount due to the individual difference in the distance dimension between the thermal heads 14 and 16 is adjusted to be constant. Since the storage amount of the storage unit 50 is saved with a small amount of information, an expensive storage unit having a larger capacity than necessary is not required, and the cost can be reduced.

Further, these first and second thermal heads 1
Since the bonding accuracy (tolerance) of the head mounting bases 14b and the rotating arm 16b of the heads 4 and 16 is generally ± 0.05 mm, when the heads 14 and 16 are mounted, at least at the time of assembly, a total of 0.1. Although there will be a variation of 2 mm, in the above-mentioned print recording on receipt paper such as supermarkets, if the generally used print record is considered to have a resolution of 200 dpi, it is within a range of 0.125 mm per 1 dot that maintains this resolution. The desired print quality can be maintained. In addition, even if the dimensional accuracy of each component is varied in addition to the bonding accuracy between the two thermal heads 14 and 16, the adjustment method can further maintain the accuracy of printing and recording.

The storage means 50 is either a flash memory, a one-time program-ROM, or a display section provided with an identification section. When this display section is used, it is inexpensive and simple without using an expensive memory or the like. With this configuration, printing accuracy can be maintained with high accuracy. When all the combination printers 10 are assembled at the same place, the storage means 50 is not used, and a seal or the like is simply used as described above, and the seal is simply written to proceed to the subsequent process together with the mechanical mechanism. You may

[0041]

As described above, in the line thermal printer of the present invention, the number of drive steps of the paper feed motor is changed to print on the print recording medium by each head for direct thermal and thermal transfer. By making them coincide with each other, it is possible to suppress the printing deviation and perform the overprinting with high accuracy.

Further, according to the print recording adjustment method for a line thermal head of the present invention, a heated direct thermal head is brought into pressure contact with the outer peripheral surface of the platen roller to thermally print the print recording medium interposed therebetween. The heat-sensitive printed recording medium is fed between the outer peripheral surface of the platen roller and the thermal transfer head, and the heated thermal transfer head is pressed against the outer peripheral surface of the platen roller so that the thermal recording of the thermal recording medium is completed. It is a method of thermally transferring the ink of the ink ribbon cassette to a predetermined printed area and superimposing it on the print recording medium.By varying the number of drive steps of the paper feed motor, each head for direct thermal and thermal transfer prints on the print recording medium. The test print line is appropriately printed and recorded, the print recording state of the test print line is identified, and the test for each test head is performed. By selecting the number of drive steps of the paper feed motor when the print lines match, and setting the paper feed amount of the print recording medium for each head with this selected number of drive steps, it is possible to suppress print misalignment and improve accuracy. Good overlay printing can be performed.

[Brief description of drawings]

FIG. 1 is a perspective view of a line thermal printer that is an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a line thermal printer that is an embodiment of the present invention.

FIG. 3 is a block diagram showing a configuration of a line thermal printer that is an embodiment of the present invention.

FIG. 4 is an explanatory diagram for explaining a relationship between two heads of a line thermal printer that is an embodiment of the present invention and a recording sheet printed and recorded by these heads.

FIG. 5 is an explanatory diagram for explaining a print pattern test by the line thermal printer that is one embodiment of the present invention.

FIG. 6 is a diagram showing an example of print recording data.

7 is a diagram showing an A character to be printed and recorded in black in the print recording data of FIG.

8 is a diagram showing a region to be printed with an ink different from the character A of the print recording data of FIG.

FIG. 9 is a diagram showing a state in which printing and recording are performed by a conventional line thermal printer.

[Explanation of symbols]

8 print recording medium (thermal paper) 10 line thermal printer (combination printer) 11 platen roller 11a rotating shaft 11c outer peripheral surface 14 first thermal head 16 second thermal head 40 paper feed motor 50 storage means L1 to L10 printing line

Claims (3)

[Claims] 1. A platen roller having a rotary shaft, which is rotatable about the rotary shaft, and a first thermal head and a second thermal head, which are arranged in the vicinity of an outer peripheral surface of the platen roller so as to face each other at a predetermined interval. A print recording medium that can be conveyed between at least two heads, a paper feed motor that rotationally drives the rotation shaft of the platen roller, and the outer peripheral surface of the platen roller and the heads that can be pressed against the outer peripheral surface. And an ink ribbon cassette having an ink ribbon containing ink, wherein the first thermal head is brought into pressure contact with the outer peripheral surface of the platen roller to thermally print the print recording medium interposed therebetween, The print recording medium on which thermal printing is performed is fed between the outer peripheral surface of the platen roller and the second thermal head, (2) A line thermal printer in which a thermal head is brought into pressure contact with the outer peripheral surface of the platen roller to thermally transfer the ink of the ink ribbon cassette to a predetermined portion of the print recording medium on which the heat-sensitive printing has been carried out, and to perform print recording. The number of driving steps of the paper feed motor is variable so that the print locations on the print recording medium in the first thermal head and the second thermal head are the same. Line thermal printer. 2. A differential value from the reference drive step number of the paper feed motor is calculated and stored in a storage means, and the storage means is used when the print recording medium is fed. 2. The line thermal printer according to claim 1, wherein the difference value read from the printer is added to the reference driving step number to drive the paper feed motor. 3. The method of adjusting a line thermal printer according to claim 1, wherein the number of drive steps of the paper feed motor is varied to change the number of the first thermal head and the second thermal head. A print line is appropriately printed and recorded on the print recording medium by each head, the print recording state of the print line is identified, and the number of driving steps of the paper feed motor when the print line of each head matches is selected. Then, the adjusting method of the line thermal printer is characterized in that the paper feed amount of the print recording medium to each of the heads is set at the selected number of driving steps.