JP2001105648A - Thermal transfer printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an amount of energizing correction parameters which are set corresponding to printing modes and a capacity of a ROM storing the energizing correction parameters and to prevent increase of cost of a thermal transfer printer. SOLUTION: There is disclosed a thermal transfer printer wherein when a plurality of heating resistors formed on a thermal head are energized to be activated, a quantity of accumulated heat is calculated based on an energizing history of each heating resistor and an energizing time period to be applied to each heating resistor is controlled in accordance with the calculated result. An energizing correction parameter to be used corresponding to a selected printing mode is compressed by a unit of word to be stored in a memory.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a thermal transfer printer, and more particularly to a thermal transfer printer capable of obtaining a good printed image by performing an appropriate energization correction in accordance with a print mode.

[0002]

2. Description of the Related Art Generally, in a thermal transfer printer, a heating element of the thermal head is moved while moving a carriage along the platen in a state where the thermal head is pressed against the platen via an ink ribbon and a recording medium such as paper. Is selectively driven based on print data, and the ink on the ink ribbon is transferred to the recording medium to print a desired image. Such thermal transfer printers are widely used as output devices such as computers and word processors because of their high recording quality, low noise, low cost, and ease of maintenance.
FIG. 2 shows such a thermal transfer printer, and is a perspective view showing a schematic configuration thereof. As shown in the figure, a flat platen 2 is disposed substantially horizontally inside a main body (not shown) of the thermal transfer printer 1. A guide shaft 3 is provided in parallel with the platen 2, and a carriage 4 is slidably mounted on the guide shaft 3 along the platen 2 in the directions of arrows R and L. The carriage 4 is provided with a thermal head 5 on which a plurality of heating elements are formed and which moves toward and away from the platen 2 by a contacting / separating mechanism (not shown).

On the carriage 4, an ink ribbon take-up bobbin 6 and a delivery bobbin 7, which will be described later, are provided. Below the take-up bobbin 5, a transmission gear (not shown) is engaged. A winding gear (not shown) is mounted coaxially via a known friction mechanism. Further, a second take-up bobbin 8 and a second delivery bobbin 9 are provided on the carriage 4, respectively. Below the second take-up bobbin 8, the take-up bobbin 5 is not shown. Second take-up gear (not shown) meshed with the take-up gear via a second transmission gear (not shown)
Are mounted coaxially via a known friction mechanism.
The take-up bobbin 6 and the second take-up bobbin 8 are respectively driven to rotate by a transmission gear that is driven to rotate by a take-up motor (not shown). It is arranged on the carriage 4 via a mechanism. Further, on the back surface of the carriage 4, the carriage 4 is suspended by a pulley (not shown).
A part of the drive belt 10 for reciprocating the drive belt along the platen 2 is fixed. Further, the platen 2
Behind the paper feed roller 11 and a plurality of pressing rollers 12
A paper feed mechanism is provided, and the paper feed roller 11 is rotated to convey the paper in a state where the paper is held between the paper feed roller 11 and the pressing roller 12. I have.

[0004] Also, rather than near the upper end of the carriage 4,
Lift gear 13 rotated by a motor (not shown)
A plurality of inclined screw teeth 13 a and screw grooves 13 b are formed at equal intervals on the outer periphery of the lift gear 13. At one corner of the upper end of the carriage 4, a detection member 14 having a sensor (not shown) disposed on the lower surface of the leading end is attached. Furthermore,
On the carriage 4, a cassette holder 2 described later is provided.
A cassette carrier 15 which is movable in five directions and makes the ribbon cassette 30 detachable is provided.
A screw hole 16 formed by projecting a plurality of screw grooves 16a meshing with the third screw groove 13b is formed. When the lift gear 13 rotates, the cassette carrier 15 moves in a direction perpendicular to the moving direction of the carriage 4.

A guide hole 18 in which a bearing (not shown) is embedded is formed on one side of the upper end of the cassette carrier 15. The guide hole 18 is formed in a guide pin 17 provided on the carriage 4. The cassette carrier 15 can smoothly move with respect to the carriage 4 by being fitted. At a position near the lower end of the cassette carrier 15, a pair of holes 19a and 19b larger than the outer diameters of the take-up bobbin 6 and the delivery bobbin 7 are formed. The take-up bobbin 6 and the sending-out bobbin 7 are inserted. Further, a square hole 19c is formed on the other side on the upper end side of the cassette carrier 15, and the detecting member 14 is inserted into the square hole 19c.

Further, the cassette carrier 15 has two fixed claws 20a and 20b integrally formed near the lower portion of the screw hole 16 and adjacent to the square hole 19c. A fixing claw 20c is also formed at the lower right corner of the cassette carrier 15 so as to project integrally with the cassette carrier 15. Further, a movable claw 21 is attached to the cassette carrier 15 so as to be rotatable in the directions of arrows A and B at a position on the left side of the lower end of the cassette carrier 15 at a position facing the fixed claw 20c. A coil spring (not shown) is wound around the center of rotation of the movable claw 21 so that the distal end of the movable claw 21 is always fixed to the fixed claw 21c.
Side, that is, in the direction of arrow B. Hook-shaped locking portions are formed at the tips of the fixed claws 20a, 20b, 20c and the movable claws 21.

Further, at a position facing the cassette carrier 15 provided on the carriage 4, a cassette holder 25 is provided at a predetermined interval in a direction parallel to the moving direction of the carriage 4, and the cassette holder 25 is provided. In
A plurality (four in the figure) of cassette holders 35 in which the ribbon cassettes 30 are detachably held, respectively, are formed. The operation of detecting a desired ribbon cassette 30 from among the ribbon cassettes 30 held by the cassette holder 25 and transferring it to the carriage 4 is performed as follows. First, as shown in FIG. 2, by moving the carriage 4 in a state where the ribbon cassette 30 is not mounted on the cassette carrier 15 in, for example, the direction of arrow R, the marker 30a of the ribbon cassette 30 is detected by the sensor of the detecting member 14. Is read, and the type of the ribbon cassette 30 held in the cassette holding unit 35 is determined.

After that, the carriage 4 is stopped at the position of the cassette holding section 35 where the desired ribbon cassette 30 is held, and the lift gear 13 is rotated for the cassette carrier 15 facing the desired ribbon cassette 30. To move to the cassette holding portion 35 side, and to the ribbon cassette 30 of the cassette holding portion 35,
0a, 20b, 20c and the movable claw 21 are engaged,
By moving the cassette carrier 15 toward the carriage 4 again, a desired ribbon cassette 30 is received. When transferring the ribbon cassette 30 from the carriage 4 to the cassette holding unit 35, the ribbon cassette 3
After the carriage 4 is moved to and stopped at the position of the cassette holding unit 35 where no 0 is mounted, the cassette carrier 15 is moved and the ribbon cassette 30 is moved to the locking portion (not shown) of the cassette holding unit 35. Then, the cassette carrier 15 is moved to the carriage 4 side.

When print information is input from an external device (not shown) in this way, the carriage 4 moves along the platen 2 and moves inside the ribbon cassette 30 held by the cassette holder 25 by the sensor of the detecting member 14. , The ribbon cassette 30 containing the desired ink ribbon is detected, the cassette carrier 15 is driven by rotating the lift gear 13, the desired ribbon cassette 30 is received on the cassette carrier 15, and printing is started. In the ribbon cassette 30, a take-up reel 31 and a take-out reel 32 which are engaged with the take-up bobbin 6 and the supply bobbin 7, respectively, when mounted on the carriage 4, are rotatably arranged. I have. The ribbon cassette 30 is provided with a pair of pinch rollers 33a and 33b respectively engaged with the second take-up bobbin 8 and the second delivery bobbin 9. A concave portion 34 into which the thermal head 5 is inserted is formed in the central portion on the side.

The ink ribbons accommodated in the ribbon cassette 30 include a hot-melt ink ribbon having a color ink layer of yellow, cyan, magenta, and black, a metallic ink ribbon having a metallic luster, There are different types of ink ribbons, such as a heat-sublimable ink ribbon coated with a heat-sublimable colored ink layer, and an ink ribbon having a heat-fusible transparent ink layer used for base printing or overcoat printing. The type can be detected by detecting a detection marker 30a such as a bar code attached to the case of the ribbon cassette 30 with a sensor of the detection member 14 provided on the carriage 4. The thermal head of the thermal transfer printer 1, a head contact / separation mechanism,
Control means (see FIG. 2) for controlling the operation of the ribbon traveling mechanism, the paper feed mechanism, and the like are provided. As shown in FIG.
And a memory 42 composed of a ROM 42a, a RAM 42b or the like having an appropriate capacity, and a controller 43 for driving the above-described units (mechanisms) of the thermal transfer printer.

The memory 42 stores at least recording information for recording as recording data, and outputs the recording data to the controller 43.
The controller 43 selectively drives the heating elements of the thermal head 5 according to print data. Further, in the memory 42, based on the recording data,
A program for controlling at least the operation of each part such as control of energization of the heating element of the thermal head 5 during recording, operation of contacting and separating the thermal head 5 from the platen 2, drive control of the carriage 4, and operation of transporting paper by a paper feed mechanism. Etc. are stored.

In such a thermal transfer printer, when recording data is input from an external device such as a computer (not shown), printing is performed based on the recording data. This printing causes the thermal head 5 to accumulate heat to increase the temperature. Therefore, the heating time of each heating element is corrected and controlled in consideration of the temperature increase so that printing unevenness does not occur. The correction of the power-on time is performed based on both the heat storage around the heating element and the heat storage over the entire substrate of the thermal head, and the power-on time to the heating element is determined by a power-on correction parameter unique to each print mode. Therefore, the calculation and the correction control are performed. The energization correction parameters are stored in the ROM 42b in the memory 42 as a data table specific to each print mode, and are stored in the memory 42 according to the print mode selected corresponding to the recording medium or the ink ribbon to be used. A corresponding energization correction parameter is extracted from the plurality of energization correction parameters stored in 42 and is used for energization correction of the heating element of the thermal head.

[0013]

A recent thermal transfer printer is capable of performing hot-melt printing or thermal sublimation printing.
Further, in this hot-melt printing, binary printing and multi-level gradation printing can be selected according to the image to be printed.
It has been required to be able to print with a plurality of lines, such as lines, 160 lines, and 190 lines. For this reason,
It is necessary to set energization correction parameters corresponding to each print mode and the number of lines, and the capacity of the ROM for storing the energization correction parameters is insufficient, and a new ROM needs to be added or a large-capacity ROM needs to be changed. However, there is a problem that the cost is increased.

[0014]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and when a plurality of heating elements formed on a thermal head are heated by energization, the heating elements are energized. In a thermal transfer printer that calculates the heat storage amount from the history and controls the energization time to each of the heating elements based on the calculation result, the energization correction parameter used in accordance with the selected print mode is compressed in word units. It is characterized by being stored in a memory.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the thermal transfer printer according to the present invention will be described below. First, as a result of checking the conventionally used energization correction parameters, it was found that the energization correction parameter data for fusing binary printing has continuous energization correction parameter data in word units. Therefore, the present invention reduces the ROM capacity of the energization correction parameter by performing compression processing of the energization correction parameter data in word units.

Hereinafter, a method of compressing the energization correction parameter will be described. A repeat counter (1 byt) of the same data that continuously energization correction parameter data in word units
e) and word data (2 bytes). In addition,
A plurality of these repeat counters and word data can be transferred. Also, by specifying the repeat counter, mixed transfer of repeat data and non-repeat data becomes possible. In addition, 80h to FFh of the repeat counter
(H is a suffix indicating that it is a hexadecimal number), the subsequent word data is repeat data, and is a two's complement expression indicating the number of repeats of the subsequent word data.

Also, the repeat counter 00H to 7FH
Indicates that the subsequent word data is non-repeat data, and has a positive expression indicating the number of subsequent non-repeat data.
As an example, the energization correction parameter data, a part of which is shown in FIG. 5, is compressed into the format shown in FIG.
Here, the first FFh is a repeat counter, and the next word data (23h23h) shown in FIG.
1)) + 1) represents word repetition. The next repeat counter 01h indicates that the next word data is non-repeat data.
(1 + 1) word data (12h13h14h15
h) is treated as transparent. The last FCh is a repeat counter, and the next word data (0Bh0Bh) shown in FIG.
((INT (−1)) + 1) words are repeated.

Although the above example is merely an example, since the energization correction parameter is composed of data in units of words as described above, the tiff compression of the energization correction parameter data in words is performed in the same manner as described above. It is possible to do. When the energization correction parameter was actually subjected to compression processing in word units as in the above example, it was possible to reduce the capacity to about 50% of the conventional capacity before compression. For this reason,
A small-capacity ROM can be used, and the cost can be reduced.

Next, the decompression processing of the compressed data will be described. First, the energization correction parameters are set corresponding to the respective print modes, so that there are as many Tiff-compressed energization correction parameters as the number of print modes. For this reason, three types are prepared as energization correction parameter decompression buffers. The first decompression buffer is an energization correction parameter decompression buffer dedicated to fusing head cleaning irrespective of the print mode.
Is a sublimation head cleaning / preheat energization correction parameter decompression buffer dedicated to the sublimation print mode, and a third decompression buffer is a variable energization correction parameter decompression buffer selected by the print mode at the time of fusing printing. It is.

Each of these decompression buffers 50 is provided with an address storage area 51 at the head thereof as shown in FIG. 4. When the compressed energization correction parameter data in the ROM 42b is decompressed, the address storage area 51 is stored in the address storage area 51. The address of the compressed destination data in the ROM 42 of the decompressed energization correction parameter is stored. Therefore, once the decompression process is completed, the address storage area 51 in the decompression buffer 50 is
Is stored in the ROM 42b, and if it is confirmed that the same address is stored thereafter, the same energization correction parameter is not decompressed. Without
The time required for the decompression process is reduced.

The decompression timings of the three types of energization correction parameter decompression buffers will be described below with reference to the flowchart of FIG. First, when the power supply of the printer is turned on, the first thawing buffer and the second thawing buffer decompress the energization correction parameter dedicated to melting head cleaning and the energization correction parameter for sublimation head cleaning / preheating.

Next, a paper feeding operation is performed by a paper feed roller, and the paper is conveyed to a printing start position. Thereafter, the cleaning operation of the thermal head is performed. At this point, the energization correction parameters for head cleaning have already been decompressed, so the head cleaning operation is immediately performed without waiting for the decompression process. Thereafter, a desired ribbon cassette required for printing is selected from among the ribbon cassettes held in the cassette holding portion of the cassette holder, and an operation of receiving the selected ribbon cassette on the cassette carrier on the carriage is performed. Selection of the recording medium, type of ink ribbon, and printing mode (selects hot-melt printing or hot-sublimation printing. If hot-melt printing is used, determine whether binary printing or multi-value printing is to be performed, and further select the line number ), The variable energization correction parameter corresponding to the print mode is decompressed.

After the desired ribbon cassette is held on the carriage, a printing operation is performed. At this point, since the necessary energization correction parameters have been decompressed, the printing operation is performed using the decompressed energization correction parameters. Accordingly, power is supplied to the heating elements of the thermal head. Even when printing for one page is completed with the same ink ribbon and printing is continued by selecting a new color ink ribbon, when the ribbon cassette is replaced, the variable energization correction parameter corresponding to the new ribbon cassette is decompressed. Therefore, when the printing is started, the decompression process has already been completed, and the energization correction to the thermal head may be performed using the decompressed variable energization correction parameter. , The waiting time until the start of printing can be shortened.

As described above, whether or not it is necessary to newly decompress the energization correction parameter is determined by checking the compressed data storage address in the ROM stored at the head address in the decompression buffer and checking the same address. If no is stored, no decompression processing is necessary, and no useless decompression processing occurs. As described above, since the decompression processing of the necessary energization correction parameter compressed data is completely completed before the operation starts, there is no need to wait for the time required for the decompression processing,
The effective printing time can be shortened.

[0025]

As described above, in the present invention,
By compressing the energization correction parameter corresponding to each print mode in word units, the capacity can be reduced, and as a result, a ROM having a small capacity can be used, so that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a flowchart showing the relationship between the timing of decompression processing of compressed data for energization correction parameters and printing operation during printing by a thermal transfer printer according to the present invention.

FIG. 2 is a perspective view illustrating a main configuration of the thermal transfer printer.

FIG. 3 is a block diagram illustrating a configuration of a control unit.

FIG. 4 is a diagram illustrating a schematic configuration of a decompression buffer.

FIG. 5 is an explanatory diagram showing a part of an example of conventional energization correction parameter data.

6 is an explanatory diagram showing energization correction parameters after compressing the energization correction parameter data of FIG. 5;

[Explanation of symbols]

 4 Carriage 5 Thermal Head 15 Cassette Carrier 25 Cassette Holder 30 Ribbon Cassette 35 Cassette Holder 40 Control Means 42b ROM 50 Decompression Buffer

Claims (1)

[Claims] When a plurality of heating elements formed on a thermal head are heated by energization, a heat storage amount is calculated from an energization history of each heating element, and the amount of heat storage is calculated based on the calculation result. In the thermal transfer printer for controlling the energization time of the printer, the energization correction parameter used in accordance with the selected print mode is compressed in words and stored in a memory.