JP2007216410A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which can simply and economically prevent a color shift in a recording result at the beginning when a roll of paper is set in the printer. <P>SOLUTION: The printer comprises a plurality of recording units 7 equipped with thermal heads 9 and ink ribbons 8, a platen roller 2 which has a plurality of the recording units 7 set at the peripheral face and can be rotatably driven, and a longitudinal recording medium 3 which is delivered out from the roll of paper 4 arranged at most upstream of a conveying route and is made conveyable by the rotation of the platen roller 2. At each of the recording units 7, an electrification period composed of an electrification time and a non-electrification time to each thermal head 9 is provisionally determined on the basis of the number of the recording paper of images. At the same time, the electrification time in the electrification period is corrected to become long in accordance with a proportion of the non-electrification time in the electrification period of an immediately precedent recording line. Each heating element is electrified accordingly, thereby carrying out recording of each recording line. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  According to the present invention, a plurality of recording units for various color inks are provided along the transport direction of a recording medium that is transported in the same direction. The present invention relates to a printer capable of recording the images of the above.

  Conventionally, in a printer that performs recording using a plurality of ink ribbons to which inks of different colors are applied, the ink of each ink ribbon is recorded by a plurality of recording heads provided corresponding to each ink ribbon. A printer that records a desired image on a recording medium by transferring it over the medium is more effective than a swing-back printer that back feeds the recording medium every time an ink layer of a different color is recorded. Attention is paid to the fact that the throughput, which is the recording speed, can be increased, and it is used.

  This printer has a platen roller that can be rotated by a stepping motor, and a plurality of colors (yellow (Y), magenta (M), cyan (C) in this conventional example) are provided on the outer periphery of the platen roller. The recording units for each color of black (K) (the same applies hereinafter) ink are arranged at predetermined intervals along the conveyance path of the recording medium.

  Each of the recording units includes a corresponding ink ribbon, recording head, and platen, and the first recording unit, the second recording unit, and the third recording unit from the upstream side in the conveyance direction of the recording medium. The unit is a fourth recording unit.

  Specifically, in each recording unit, the recording head is disposed so as to face a recording medium conveyed through a conveyance path via the ink ribbon, and the recording head and the platen include the ink ribbon and the recording medium. It is possible to relatively press-contact through the medium.

  The recording medium has a long shape, and can be transported from the upstream side to the downstream side in the transport path by the rotation of the platen roller.

  In a printer having such a configuration, in order to record a desired image on a recording medium, first, energization of the thermal head of the first recording unit is started. For example, a yellow (Y) ink ribbon The ink layer is thermally transferred to record the first image on the recording medium. Thereafter, the area where the first image is recorded is conveyed to a second recording unit disposed on the downstream side in the conveyance path, and the thermal head of the second recording unit is placed on the first image, for example, magenta ( The second image using the ink layer of the ink ribbon of M) is overlaid and recorded.

  Next, similarly, the area where the first image and the second image are recorded is transported to the third recording unit disposed on the downstream side in the transport path, and the third recording unit is placed on the first image and the second image. With the thermal head, for example, a third image using an ink layer of a cyan (C) ink ribbon is overlaid and recorded.

  Then, the region where the first image to the third image are recorded is transported to the fourth recording unit disposed on the most downstream side in the transport path, and the thermal head of the fourth recording unit is placed on the first image to the third image. For example, a fourth image using an ink layer of a black (K) ink ribbon is overlaid and recorded to form a desired color image on a recording medium (see, for example, Patent Document 1).

JP 2003-291388 A

  Here, when paying attention to the recording medium, the recording medium is fed out from the paper roll disposed at the uppermost stream in the conveying path into the conveying path and guided to the outer periphery of the platen roller by the paper feed roller. Transfer of the ink layer of the ink ribbon provided in each recording unit at a position facing each thermal head from the first recording unit to the fourth recording unit by the rotation of the platen roller guided by winding. Then, the paper is discharged to the outside of the printer while being guided by the paper discharge roller, and is cut to a predetermined length by a cutting mechanism (not shown).

  When such a recording medium is conveyed along the outer periphery of the platen roller to perform the first recording after a new paper feed roller is disposed in the printer, the recording start position of the leading end of the recording medium Is transported to a position facing the thermal head of the first recording unit located on the upstream side of the transport path, the amount of winding around the platen roller is small. Therefore, when the first image in the first recording unit is recorded on the recording medium, the friction between the platen roller and the recording medium is reduced, and slippage occurs in the conveyance. Therefore, the first image has a recording length shorter than the desired recording length.

  In the subsequent recording of the second image in the second recording unit, the recording medium is wound around the platen roller at a winding amount that is about half of the normal amount, so that the friction between the platen roller and the recording medium is reduced. The recording of the recording medium was not sufficiently ensured, and the recording medium was slipped, and the second image was recorded with a recording length shorter than the desired recording length (however, the recording length longer than the first image) Becomes).

  Further, when the third image is recorded in the third recording unit, similarly, since the friction between the platen roller and the recording medium cannot be sufficiently secured, a slip occurs in the conveyance of the recording medium, and the third image is also recorded as desired. The recording length was shorter than the length (however, the recording length was longer than that of the second image).

  The recording medium is in a state where the recording medium is wound around the platen roller with a substantially normal winding amount when the fourth image is recorded in the fourth recording unit, and therefore the friction between the platen roller and the recording medium. Further, since the recording medium is firmly gripped, it is difficult for the conveyance to slip, and the fourth image is recorded with a substantially desired recording length.

    As described above, the initial recording result when the paper roll is disposed in the printer is a frictional force proportional to the contact area between the recording medium and the platen roller until the recording medium is sufficiently wound around the outer periphery of the platen roller. Since there is a difference in the conveyance amount of the recording medium depending on the size, a color shift from the first image to the fourth image occurs in the initial recording result, and a satisfactory recording result is not obtained.

  In addition, regarding the recording of the image after being sufficiently wound around the outer periphery of the platen roller, the conveyance slip as described above does not occur because the platen roller is wound around the outer periphery with an appropriate grip force.

  In addition, the problem of color misregistration in the printing result caused by the difference in the magnitude of friction proportional to the contact area between the printing medium and the platen roller, as described above, is due to the fact that the paper roll is initially disposed in the printer. During recording, the leading end of the recording medium is idlely conveyed to the discharge roller disposed at the most downstream side in the conveying path, and the recording medium is sufficiently wound around the platen roller. It is possible to take measures to ensure the friction necessary for conveyance, but in this case, wasteful consumption of the recording medium increases, which is uneconomical.

  Therefore, as one method of solving this color misregistration problem, the recording length of an image recorded in each recording unit is adjusted by adjusting the energization cycle of the thermal head based on the number of recorded images in each recording unit. A method for adjusting the thickness can be considered.

  However, when the recording length is adjusted by changing the energization cycle, the ratio of the heat generation time of the thermal head in one energization cycle required for recording of one recording line is different (increases in the case of the above-described countermeasure against slip of the recording medium). As a result, the recording density varies.

  That is, when the energization period is constant, as shown in FIG. 3 (1), the heating time and the cooling time for the thermal head are uniform for all the recording lines, and therefore, the recording density is less likely to be uneven. However, when the energization period is changed, as shown in FIG. 3B, the energization time and cooling time for the thermal head are different, and therefore the transfer density of the ink layer of the ink ribbon varies depending on the recording line. Good recording results could not be obtained.

  Specifically, if the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line is long, the thermal head proceeds to cool down, and the thermal head is not supplied even if power is supplied for recording of the next recording line. Is not heated enough to transfer the ink layer, the transfer density of the ink layer becomes thin, and conversely, if the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line is short, It is conceivable that the head is not dissipated and the thermal head becomes overheated during the recording of the next recording line, and the transfer of the ink layer is excessively made and the transfer density becomes high.

  Therefore, the present invention eliminates the color shift in the initial recording result when the paper roll is mounted in the printer by changing the energization cycle to the thermal head of each recording unit, and further, the occurrence of density unevenness is reduced by the energization cycle. It is an object of the present invention to provide a printer that can solve the problem by correcting the image and obtain a good recording result.

  In order to achieve the above object, a printer according to the present invention includes a plurality of recording units including a thermal head in which heating elements are arranged in a line, an ink ribbon drawn around the thermal head, and the plurality of recording units. A platen roller that can be driven to rotate and arranged on the outer peripheral surface side at a predetermined interval, and a paper roll that is arranged on the most upstream side of the conveyance path and can be conveyed by the rotation of the platen roller. A thermal head provided in each recording unit, in order from the recording unit arranged on the upstream side of the recording medium conveyance path with respect to the recording medium, the recording medium and the ink ribbon. The platen roller is rotated in a state of being pressed against the platen roller, and the ink layer of the ink ribbon is based on the recording data. A printer that obtains a recording result of a predetermined length by transferring and superimposing images for each recording recording line, and in each recording unit, based on the number of recorded images, the energization time and the non-energization time for each thermal head. Tentatively determining the energization cycle, and by energizing each heating element by correcting the energization time in the energization cycle to be longer according to the ratio of the non-energization time in the energization cycle of the immediately preceding recording line, Each recording line is recorded.

  Here, the energization cycle of the thermal head tentatively determined in the present invention is, specifically, in each recording unit, when the paper roll is mounted in the printer, the recording medium is conveyed on the outer periphery of the platen roller. It is determined that the energization cycle is gradually shortened as the number of recorded images increases until it is sufficiently wound around the path, and finally changed to the normal energization cycle.

  By performing such control, it is possible to adjust the recording length of an image formed in the same recording unit in accordance with the number of recordings at the time of recording on the recording medium in which the slip occurs during conveyance.

  Further, in the same number of recordings between the recording units, the energization cycle of the thermal head of each recording unit is arranged on the upstream side of the transport path of the recording medium together with the change of the winding amount of the platen roller of the recording medium. From the recording unit to the recording unit disposed on the downstream side, the energization cycle is set so as to be shortened in order.

  By performing such control, it is possible to adjust the recording length of the same number of recorded images in each recording unit during recording on a recording medium in which slippage occurs in conveyance.

  In this way, by correcting the energization period for the heating element of the thermal head of each recording unit based on the number of recorded images, the recording length of the image recorded in each recording unit is adjusted and the problem of color misregistration is solved. can do.

  In addition, by adjusting the energization time and non-energization time within the energization cycle so that the energization time in the energization cycle becomes longer according to the ratio of the non-energization time in the energization cycle of the immediately preceding recording line, density unevenness can be generated. Can be suppressed.

  Further, the ink ribbons arranged in the recording units are different in the color of the ink layer.

  Thus, by making the colors of the ink layers of the ink ribbons arranged in the respective recording units different from each other, a good recording result can be obtained for a color recording image.

  As described above, according to the printer of the present invention, it is possible to easily and economically prevent color misalignment and density unevenness in the initial recording when the paper roll is mounted in the printer. The result can be obtained.

  Hereinafter, an embodiment of a printer of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram for explaining a main part of the printer of this embodiment.

  In the printer 1 according to the embodiment of the present invention, as shown in FIG. 1, a platen roller 2 that can be driven to rotate is disposed inside a housing (not shown). The platen roller 2 is coated with a platen rubber (not shown) made of an elastic rubber or the like on the outer periphery, and the outer shape is formed in a cylindrical shape. The platen roller 2 has a rotation shaft 2a formed at the center of rotation, and the rotation shaft 2a is pivotally supported by a bearing (not shown). The rotating shaft 2a is gear-coupled to a stepping motor (not shown) as a driving source through a driving gear (not shown), and the platen roller 2 can be driven to rotate in the direction of arrow A by the rotation of the stepping motor. It has become.

  Further, the belt-like long recording medium 3 is wound around the outer peripheral surface of the platen rubber by frictional contact. In the following, the recording medium 3 has a strip-like and long mount (not shown), and on the surface of this mount, for example, the length direction dimension is set to be slightly shorter than the dimension between adjacent recording units 7. A case where the recording medium 3 on which a plurality of rectangular labels are attached at predetermined intervals will be described. That is, in the present embodiment, the recording medium 3 having the length of four labels is wound in contact with the platen roller 2 in the conveyance path of the recording medium 3 on the outer periphery of the platen roller 2. It is assumed that

  The recording medium 3 is fed into the transport path from a paper roll 4 arranged at the uppermost stream in the transport path, guided by the paper feed roller 6 and wound around the outer periphery of the platen roller 2, After being used for recording, the paper is discharged out of the printer 1 while being guided by a paper discharge roller 6.

  A plurality of colors (four colors of yellow (Y), magenta (M), cyan (C), and black (K) in the conventional example, the same applies hereinafter) are provided on the outer peripheral side of the platen roller 2. A recording unit 7 for each color of ink is arranged at a predetermined interval along the conveyance path of the recording medium 3.

  Each of the recording units 7 includes a thermal head composed of a line head in which a corresponding one of the ink ribbons 8 and a plurality of heat generating elements are formed in the longitudinal direction parallel to the axial direction of the rotation shaft 2a of the platen roller 2. A second recording unit including a first recording unit 7Y including a yellow (Y) ink ribbon 8Y and a magenta (M) ink ribbon 8M from the upstream side in the conveyance direction of the recording medium 3; A unit 7M, a third recording unit 7C having a cyan (C) ink ribbon 8C, and a fourth recording unit 7K having a black (K) ink ribbon 8K.

  Specifically, in each recording unit 7, the thermal head 9 is disposed so as to face the recording medium 3 conveyed along the conveyance path via the ink ribbon 8, and the thermal head 9 includes the ink ribbon. 8 and the recording medium 3 can be brought into and out of contact with the platen roller 2 (head down / head up). An ink ribbon 8 is guided by a plurality of pinch rollers (not shown) between each thermal head 9 and the recording medium 3 wound around the platen roller 2, and between the platen roller 2 and the thermal head 7. Has been routed around. The ink ribbon 8 has an ink layer of a desired color formed on a surface of a base material (not shown) made of a long resin film or the like that faces the platen roller 2, and rotates the winding core 11. By doing so, the supply core 12 can be wound around the winding core 11. In addition, the other surface of the ink ribbon 8 on which the ink layer is not formed can be brought into sliding contact with the heating element of the thermal head 9.

  Then, the thermal head 9 in each recording unit 7 is simultaneously or at any time head down to press the platen roller 2 through the ink ribbon 10 and the recording medium 3 and rotate the platen roller 2 in the direction of arrow A. Recording is performed on the conveyed recording medium 3.

  The printer 1 according to this embodiment stores the energization cycle (consisting of energization time and non-energization time) of the thermal head 9 of each recording unit 7 based on the number of recorded images in a non-volatile memory (not shown). is doing. This energization cycle is used as a countermeasure against the slip of conveyance of the recording medium 3 and is intended to perform recording by correcting the normal energization cycle at the time of initial recording when the paper roll 4 is mounted in the printer 1. In this embodiment, each recording unit 7 refers to the energization period stored in the nonvolatile memory at the time of image recording, and changes the energization period of the thermal head according to the number of recorded images. To control.

  That is, when the rotation speed of the platen roller 2 is constant, the image recording length becomes longer when the energization cycle for the thermal head is lengthened and becomes shorter when the thermal head is shortened.

  Therefore, when no slip has occurred in the conveyance of the recording medium 3 with respect to the energization pulse of the stepping motor as the drive source of the platen roller 2 shown in FIG. 2A, as shown in FIG. Although the thermal head 9 is energized in a normal energization cycle, as described above, the recording medium is still wound around the outer periphery of the platen roller 2 at the time of initial recording when the paper roll 4 is mounted in the printer. If not, in each recording unit 7, as shown in FIG. 2 (3), the energization cycle for the thermal head 9 is lengthened, and the recording length is increased for the recording medium 3 on which the conveyance slips. Control to do.

  Specifically, the energization cycle of the thermal head 9 is such that the recording medium 3 is moved to the outer periphery of the platen roller 2 from the time when the first image is recorded in each recording unit 7 after the paper roll 4 is arranged in the printer. Until the time when the first image is recorded until it is sufficiently conveyed to the conveyance path, the energization cycle is gradually shortened in proportion to the number of recorded images. Adjust to change to the energization cycle. Further, between the recording units 7, the recording disposed on the downstream side from the recording unit 7 </ b> Y disposed on the upstream side of the conveyance path of the recording medium 3 with the change in the winding amount of the platen roller 2 of the recording medium 3. The unit 7K is adjusted in order so that the energization period corresponding to the number of recorded sheets becomes shorter. As described above, the recording length of the image recorded in each recording unit 7 can be adjusted by controlling the energization cycle of each recording unit 7 to the thermal head 9 in consideration of the slip generated in the conveyance of the recording medium 3. And the problem of color misregistration can be solved.

  Furthermore, in the present embodiment, the energization time of the energization cycle for each heating element of the thermal head 9 in each recording unit 7 is set according to the ratio of the non-energization time of the energization cycle at the time of recording on the immediately preceding recording line. Specifically, the longer the non-energization time is corrected, the longer the energization time in the energization period is, and the control is performed so that each heating element is energized by the energization time after the correction and the next recording line is recorded. Has been.

That is, the non-energization time at the time of recording on the immediately preceding recording line is measured, and the energization cycle is adjusted according to the following equation based on the non-energization time to obtain the energization time required for recording the next recording line. W is the energization time after correction, B is the energization time in the provisional energization cycle stored in the nonvolatile memory, and f is a correction function based on the non-energization time. When the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line is long, f> 1, and conversely, the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line. If f is short, f <1.
W = B × f

  By applying such control and adjusting the energization time and the non-energization time within the energization cycle, the occurrence of density unevenness can be suppressed.

  When the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line is long, f> 1 and the adjustment is made so that the energization time is longer than the normal energization time. The thermal head is energized longer than the normal energization time for energization for recording the next recording line, so that the ink layer is sufficiently heated to transfer the ink layer to an appropriate transfer density. Can be secured.

  On the contrary, when the cooling time (non-energization time) in the energization cycle for recording of the immediately preceding recording line is short, f <1, and by adjusting the energization time to be shorter than the normal energization time, The thermal head that is in an overheated state is energized shorter than the normal energization time for energization for recording the next recording line, so that the heating temperature is adjusted to a temperature sufficient for the transfer of the ink layer. An appropriate transfer density of the layer can be ensured.

  The length and degree of the non-energization time in the energization cycle can be determined by converting the ratio of the non-energization time in the energization cycle and comparing it with the ratio in the normal time. The correction function f is set in advance based on the non-energization time, the table is stored in the nonvolatile memory, and the table is referred to according to the ratio of the non-energization time of the immediately preceding recording line. .

  In this way, by adjusting the energization time at the time of recording of the next recording line in consideration of the non-energization time of the immediately preceding recording line, as shown in FIG. Since it is possible to ensure the temperature, it is possible to prevent the occurrence of recording density unevenness.

  More specifically, the energization cycle for each thermal head 9 in the case where desired color recording is performed on each label of the recording medium 3 immediately after mounting a new paper roll by the printer 1 having the above-described configuration, A method for correcting the ratio between the energization time and the non-energization time will be described.

  First, energization of the thermal head 9 of the first recording unit 7Y is started, and the ink layer of the yellow (Y) ink ribbon 8Y is thermally transferred to record the first image on the first label of the recording medium 3. .

  At this time, since the recording medium 3 is hardly wound around the platen roller 2 and the frictional force acting between the two is very small, a large slip occurs in the conveyance of the recording medium 3. Therefore, the thermal head 9 is energized with the longest energization cycle. As a result, the first image is recorded with a logically long recording length on the recording medium 3 that is conveyed while being largely slipped. As a result, a first image having a desired recording length can be obtained.

  When recording an image, as described above, the energization time in the energization cycle of each heating element of the thermal head 9 is set to the energization cycle of each heating element of the thermal head 9 at the time of recording of the immediately preceding recording line. Correction is made in accordance with the ratio of the non-energization time, and each heating element is energized by the energization time after the correction, so that the next recording line is recorded (the same applies to the following recording units).

  As described above, even when the recording length is adjusted by changing the energization cycle, the heat generation time of the thermal head 9 occupying one energization cycle required for recording of one recording line is set as the energization time in the immediately preceding recording line. The adjustment of the non-energization time can be performed to suppress variations in recording density.

  Subsequently, the first label on which the first image is recorded is transported to the second recording unit 7M disposed on the downstream side in the transport path, and the thermal head 9 of the second recording unit 7M is placed on the first image. Then, the second image using the ink layer of the magenta (M) ink ribbon 8M is overlaid and recorded.

  At this time, the recording medium 3 is not so wound around the platen roller 2 and the friction force acting between the two is small, so that a slight slip occurs in the conveyance of the recording medium 3. Therefore, the thermal head 9 is energized with an energization cycle that is shorter than the energization cycle during the first image recording of the first recording unit 7Y and longer than the normal energization cycle. As a result, the second image is recorded with a slightly longer recording length on the recording medium 3 that is conveyed while slipping a little, so that the second image having a desired recording length is changed to the first image. It can be obtained repeatedly.

  At this time, the first recording unit 7Y records the second first image on the second label of the recording medium 3.

  At this time, as described above, the slip generated in the conveyance of the recording medium 3 is slightly large. Therefore, the thermal head 9 is shorter than the energization cycle at the time of the first image recording and is shorter than the normal energization cycle. Energization is performed with a long energization cycle.

  Next, similarly, the label on which the first image and the second image are recorded is transported to the third recording unit 7C disposed on the downstream side in the transport path, and the third recording unit is placed on the first image and the second image. With the 7C thermal head 9, the third image using the ink layer of the cyan (C) ink ribbon 8C is overlaid and recorded.

  At this time, the recording medium 3 is not sufficiently wound around the platen roller 2, and the frictional force acting between the both 3 and 2 is still small, so that a slight slip occurs in the conveyance of the recording medium 3. Therefore, the thermal head 9 is energized at an energization cycle that is shorter than the energization cycle during the second image recording of the second recording unit 7M and longer than the normal energization cycle. As a result, the third image is recorded with a slightly longer recording length on the recording medium 3 that is conveyed while slipping slightly smaller. As a result, the third image having a desired recording length is converted into the first image. And overlaid on the second image.

  At this time, the first recording unit 7Y records the third first image on the third label of the recording medium 3.

  At this time, as described above, since the slip generated in the conveyance of the recording medium 3 is small, the thermal head 9 is usually shorter than the energization cycle at the time of recording the first image of the second sheet. Energization is performed with an energization cycle set longer than the energization cycle.

  Also in the second recording unit 7M, the second second image is recorded on the second label of the recording medium 3.

  At this time, since the recording medium 3 is in a state in which slipping is likely to occur as described above, the thermal head 9 is shorter than the energization cycle at the time of recording the second image of the first sheet, and the normal energization cycle. Energization is performed with a longer energization cycle.

  Finally, the label on which the first image to the third image are recorded is conveyed to the fourth recording unit 7K disposed on the most downstream side in the conveyance path, and the fourth recording unit is placed on the first image to the third image. The fourth image using the ink layer of the black (K) ink ribbon 8K is recorded with the 7K thermal head 9, and a desired color image is formed on the label of the recording medium 3.

  At this time, since the recording medium 3 is almost wound around the platen roller 2 and the friction force acting between the two and the two can be almost ensured, slip generated when the recording medium 3 is conveyed is extremely small. Get smaller. Therefore, the thermal head 9 is energized with an energization cycle that is set to be shorter than the energization cycle during the third image recording of the third recording unit and slightly longer than the normal energization cycle. Thus, as a result of recording an image with a recording length that is logically slightly longer with respect to the recording medium 3 conveyed while being slipped small, a fourth image having a desired recording length is changed from the first image to the third image. It can be obtained overlaid on the image.

  In the first recording unit 7Y, the fourth first image is recorded on the fourth label of the recording medium 3.

  At this time, as described above, since the slip generated in the conveyance of the recording medium 3 is extremely small, the thermal head 9 is shorter than the energization cycle at the time of recording the first image on the third sheet, Energization is performed with an energization cycle set slightly longer than the normal energization cycle.

  In the second recording unit 7M, the third second image is recorded on the third label of the recording medium 3.

  At this time, as described above, since the slip generated in the recording medium 3 is extremely small, the thermal head 9 is shorter than the energization cycle at the time of recording the second image on the second sheet, and is normal. Energization is performed with an energization cycle set longer than the energization cycle.

  In the third recording unit 7C, the second third image is recorded on the second label of the recording medium 3.

  At this time, as described above, since the slip generated in the recording medium 3 is extremely small, the thermal head 9 is shorter than the energization cycle at the time of recording the second image of the first sheet and is normally energized. Energization is performed with an energization cycle set longer than the cycle.

  Then, after the fourth image is superimposed on the first image to the third image in the fourth recording unit 7K and the four color ink ribbons 8 are superimposed to form a desired color image, the recording medium 3 is removed. The paper is guided to the downstream side of the conveyance path of the recording medium 3 by the paper roller 6 and discharged out of the printer 1.

  At this time, the recording medium 3 is wound around the platen roller 2 along the entire length of the conveying path on the outer periphery of the platen roller 2 and is gripped by a predetermined frictional force of the platen rubber 2a. In consideration, it is not necessary to adjust the energization cycle for each thermal head 7. Therefore, when each image is recorded in each recording unit 7 thereafter, control is performed so that each thermal head 9 is energized in a normal energization cycle.

  Thus, by controlling the energization cycle of each recording unit 7 to the thermal head 9, the recording length of the image recorded in each recording unit 7 can be adjusted, and the paper roll 4 is mounted in the printer 1. It is possible to easily and economically prevent color misregistration in the initial recording result.

  Further, even when the recording length is adjusted by changing the energization cycle, it is possible to vary the recording density by equalizing the ratio of the heat generation time of the thermal head to one energization cycle required for recording of one recording line. And a good recording result can be obtained.

  Further, by changing the color of the ink layer of the ink ribbon 8 disposed in each recording unit 7 as in the present embodiment, a good recording result can be obtained for a color recording image.

  In addition, this invention is not limited to the said embodiment, A various change is possible as needed.

  For example, in this embodiment, the ink ribbon 8 has been described as having formed an ink layer of yellow (Y), magenta (M), cyan (C), and black (K), but the color of the ink layer is The color is not limited to this, and only a single color such as black may be used.

  In the above-described embodiment, the adjustment of the energization time in the energization cycle is focused on the ratio of the non-energization time in the energization cycle and is corrected so that the energization time in the energization cycle becomes longer as the non-energization time becomes longer. However, this focuses on the ratio of the energization time in the energization cycle, and is equivalent to the control for correcting the energization time in the energization cycle to be shorter as the energization time is longer.

Schematic explaining the main part of a printer of an embodiment of the present invention Timing chart explaining the control of the energization cycle for the thermal head of the recording unit in the printer of this embodiment in relation to the pulse of the driving stepping motor of the platen roller (1) is a conceptual diagram showing the relationship between the general energization / non-energization time and the head temperature when the energization period is constant, and (2) is the energization period in the conventional control. FIG. 3 is a conceptual diagram showing the relationship between energization / non-energization time and head temperature when the thermal head is changed, and (3) is the energization of the thermal head when the energization cycle is changed in the control of the present embodiment. The conceptual diagram which shows the relationship between the time of non-energization and head temperature.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 2 Platen roller 2a Rotating shaft 3 Recording medium 4 Paper roll 5 Paper feed roller 6 Paper discharge roller 7 Recording unit 7Y 1st recording unit 7M 2nd recording unit 7C 3rd recording unit 7K 4th recording unit 8 Ink ribbon 8Y Yellow Ink Ribbon 8M Magenta Ink Ribbon 8C Cyan Ink Ribbon 8K Black Ink Ribbon 9 Thermal Head 11 Winding Core 12 Supply Core

Claims (2)

A plurality of recording units provided with a thermal head in which heating elements are arranged in a line and an ink ribbon drawn around the thermal head, and the plurality of recording units can be brought into contact with and separated from the outer peripheral surface side at a predetermined interval. A rotationally driven platen roller, and a long recording medium that is fed from a paper roll disposed at the uppermost stream of the conveyance path and can be conveyed by the rotation of the platen roller. On the other hand, in order from the recording unit arranged on the upstream side in the recording medium conveyance path, the platen roller is placed in a state in which the thermal head provided in each recording unit is pressed against the platen roller via the recording medium and the ink ribbon. Rotate, transfer the ink layer of the ink ribbon for each recording line based on the recording data, and overlay the images A printer to obtain a long recording result,
In each of the recording units, an energization period consisting of an energization time and a non-energization time for each thermal head is provisionally determined based on the number of recorded images, and as the non-energization time in the energization period of the immediately preceding recording line increases. A printer characterized in that the energization time in the energization cycle is corrected so as to become longer and each heating element is energized to record each recording line. The printer according to claim 1, wherein the ink ribbons disposed in the respective recording units have different ink layer colors.

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