JP5765021B2 - Printer - Google Patents

Description

  The present invention relates to a printer that performs printing while feeding paper from a paper feed roll.

  2. Description of the Related Art Conventionally, many printers that perform printing while causing a print head to elastically contact with a platen roller and superposing and feeding an ink ribbon and a paper between them are known. In order to perform high-definition printing of images and the like in such a printer, it is necessary to control the paper conveyance speed with high accuracy in conjunction with the operation of the print head, and many techniques for that purpose have been disclosed. Among them, as shown in Patent Document 1 below, the paper is gripped on the circumferential surface of the grip roller by sandwiching the paper between a grip roller having a minute protrusion on the surface and a pinch roller facing the grip roller. In addition, a technique for controlling the sheet conveyance speed by controlling the rotation speed of the grip roller is known.

  When such a technique is introduced into a printer in which paper is formed as a continuous paper feed roll, it generally has a form as schematically shown in FIG. The paper 501 is drawn from the paper supply roll 501a in the paper supply direction (X direction indicated by the arrow in the figure), and is superposed on the ink ribbon 502 running between the ribbon rolls 502A and 502B, and the platen roller 504 and the print head 503 are overlapped. Are sent to a printing position P formed between them. When the printer is a thermal printer, a plurality of heating elements (not shown) are arranged side by side in a direction perpendicular to the conveyance direction of the paper 501 on the contact surface of the print head 503 with the paper 501, and each of the heating elements has a predetermined value. Printing is performed by energizing and generating heat with this pattern. The sheet 1 is sandwiched between the grip roller 521 and the pinch roller 524, and the position of the sheet 1 is regulated in the transport direction by the gripping roller 521 being driven by the stepping motor 522 via the pulleys 521a and 522a and the belt 523. A motor 512 is also provided to control the feed amount and tension of the paper 1, and the feed roll 501 a can be driven via the pulleys 512 a and 511 and the belt 513 while monitoring the rotation amount by the encoder 543. .

  When the apparatus configuration as described above is adopted and the conveyance direction of the paper 501 at the time of printing is changed to the direction opposite to the paper feeding direction (Y direction indicated by an arrow in the drawing), printing is performed by performing the following control. It will cause the action to be performed. First, a reference command for performing target printing is output from the print command unit 531 to each unit. In response to the reference command, the rotation pattern setting unit 532 determines and outputs the conveyance distance and conveyance speed of the paper 501 during printing, and the stepping motor control unit 533 converts it into a specific control signal based on the output value. Then, the gripping roller 521 is driven by outputting it to the stepping motor 522 and operating it. Further, the motor control unit 534 determines the rotation amount and rotation speed of the paper feed roll 501a based on the output value from the rotation pattern setting unit 532, and always keeps the paper even when the paper feed roll 501a is near the maximum diameter or the minimum diameter. By controlling the pass line 501 to be slightly loosened as indicated by 501C and 501D in the figure, the influence on the paper 501 at the printing position P is prevented. In this way, the conveyance speed of the paper 501 at the printing position P is determined only by the rotation of the grip roller 521. During printing, the paper 501 can be conveyed at a constant speed by rotating the grip roller 521 at a constant rotation speed.

  While the sheet 501 is conveyed as described above, the print head 503 is controlled as follows. First, in response to a reference command from the print command unit 531, the print operation pattern setting unit 535 creates a print operation pattern for each line, and the print head control unit 536 applies each heating element of the print head 503 according to the print operation pattern. Energized. Then, each heating element generates heat according to the energization amount, whereby the dye on the ink ribbon 502 is transferred to the paper 501 and printing is performed. Such a heat generation pattern change as a printing operation of the print head 503 is also performed at a constant speed.

As described above, at the time of printing, the conveyance speed of the paper 501 and the heat generation pattern change as the printing operation by the print head 503 are each performed at a constant speed, so that printing can always be performed under the same conditions. Therefore, even when a plurality of colors are overlaid on the same print area of the paper 501 , stable and high-quality printing can be performed without causing a shift in the print position.

JP 2004-161423 A

  However, when using a grip roller having fine protrusions on the surface as described above, protrusion traces due to the fine protrusions remain on the paper surface, and in recent years, improvements have been required in printing where higher image quality is desired. Yes.

  In order to drastically prevent such protrusion marks, it is necessary to avoid using the above-mentioned grip rollers with minute protrusions in the printer components. It is conceivable that slip occurs between the rollers for transporting the paper (conveyance rollers), the paper transport speed fluctuates, and high-precision printing cannot be performed.

  An object of the present invention is to effectively solve such problems. Specifically, a grip roller having minute protrusions is not used and no protrusion trace is generated, and the paper is conveyed stably during printing. It is another object of the present invention to provide a printer that can appropriately maintain printing conditions and can realize high-precision printing.

  In order to achieve this object, the present invention takes the following measures.

That is, in the printer of the present invention, a plurality of color dyes are sequentially provided on the paper fed from the paper supply roll at the printing position set between the platen roller and the print head that elastically contacts the platen roller . while feeding in a state of being polymerized with the ink ribbon, the printing operation in which Ru gives a signal from the print head control unit to the print head, by repeating the operation in which reversely rotates the feed roll, for the same print area A printer that performs printing of each color individually, and includes a paper feed roll driving unit for driving the paper feed roll, and the rotation speed of the paper feed roll driven by the paper feed roll drive unit is a sheet at a printing position. together configured to define a conveying speed of the conveying distance said feed roll to detect the conveying distance of the sheet to be conveyed during the rotation of a predetermined amount Based on the output means, and the detected value of the paper transport distance corresponding to the rotation amount of the paper feed roll and the rotation amount of the paper feed roll, the paper transport is performed regardless of the change in the winding diameter of the paper feed roll. Rotational speed correction means for creating a rotational speed correction amount for correcting the rotational speed at the time of printing of the paper feed roll so that the speed is substantially constant between the printing areas, and during printing of the printing area The rotational speed correction amount is created based on the detected value of the paper feed distance corresponding to the rotation amount of the paper feed roll and the rotation amount of the paper feed roll, and the printing is performed using the rotational speed correction amount. The rotation speed of the paper feed roll is corrected between the completion of printing for the area and the start of printing for the next print area, and the rotation of the paper feed roll is performed while printing each color on the same print area. Keep the speed the same It is characterized by the Turkey be printed while maintaining the relationship between the conveying speed of the sheet and the printing operation speed of the print head in the same.

  With this configuration, the printing speed consisting of the relative relationship between the paper conveyance speed during printing and the printing operation speed in the print head is always kept the same while the paper speed during printing is determined by the rotation speed of the paper feed roll. Therefore, printing can be performed with high accuracy without using a grip roller having fine protrusions.

The front Symbol sheet feed roller corresponding to the rotation amount of the rotating amount and the sheet feeding roll and conveying distance detection means for detecting the conveying distance, the feed roll sheet conveyed during the rotation of a predetermined amount Based on the detected value of the paper transport distance, the rotation of the paper feed roll during printing is performed so that the paper transport speed is substantially constant between the printing areas regardless of the change in the winding diameter of the paper feed roll. since further comprising a rotational speed correction means for creating a rotational speed correction amount for correcting the speed, can be corrected rotational speed of the sheet feed roller in response to changes in the winding diameter of the paper feed roll, when printing paper The conveyance speed can be kept almost constant.

Further, the rotational speed correction amount is created based on the rotation amount of the paper feed roll and the detected value of the transport distance of the paper corresponding to the rotation amount of the paper feed roll during printing of the print area, and the rotational speed using the correction amount is corrected rotational speed of the feed roll between the completion of printing on the print area to start printing for the next printing region, a pair to print the respective colors in the same printing area Since the rotation speed of the paper feed roll is kept the same during the printing, the rotation speed correction amount created during the printing is reflected in the printing of the next printing area and the time can be shortened while keeping the same. Even when a plurality of colors are overlaid on the printing area, control error can be eliminated by keeping the rotation speed constant, and high-quality printing can be performed without causing printing misalignment.

On the other hand, in the printer of the present invention according to another configuration, a plurality of color dyes are fed to a sheet fed from a paper feed roll at a printing position set between a platen roller and a print head that elastically contacts the platen roller. By repeating the printing operation of giving a signal from the print head control unit to the print head and the operation of rotating the paper feed roll while feeding the ink ribbon in a state of being superposed with the ink ribbons provided in order, the same printing is performed. A printer that individually prints each color on an area, and includes a paper feed roll driving unit for driving the paper feed roll, and a rotational speed of the paper feed roll driven by the paper feed roll drive unit is It is configured to regulate the paper conveyance speed at the printing position, and detects the conveyance distance of the paper conveyed while the paper feed roll rotates a predetermined amount. Based on the conveyance distance detection means, and the detected value of the conveyance distance of the paper corresponding to the rotation amount of the paper feed roll and the rotation amount of the paper feed roll, Printing speed correction means for creating a printing speed correction amount for correcting the printing operation speed of the print head so as to correspond to a change in the conveyance speed, and the rotation amount of the paper feed roll during printing in the printing area And a printing speed correction amount is created based on the detected value of the conveyance distance of the paper corresponding to the rotation amount of the paper feed roll, and the printing speed correction amount is used to perform the next printing from the completion of printing on the printing area. The print operation speed of the print head is corrected until the start of printing for the print area, and the print operation speed of the print head is kept the same while printing each color in the same print area. , Wherein the printing while maintaining the relationship between the conveying speed of the sheet and the printing operation speed of the print head in the same.
With this configuration, the printing speed consisting of the relative relationship between the paper conveyance speed during printing and the printing operation speed in the print head is always kept the same while the paper speed during printing is determined by the rotation speed of the paper feed roll. Therefore, printing can be performed with high accuracy without using a grip roller having fine protrusions.
The front Symbol sheet feed roller corresponding to the rotation amount of the rotating amount and the sheet feeding roll and conveying distance detection means for detecting the conveying distance, the sheet feeding roll of sheet conveyed during the rotation of a predetermined amount Printing speed correction for correcting the printing operation speed of the print head so as to correspond to the change in the paper conveyance speed accompanying the change in the winding diameter of the paper feed roll based on the detected value of the paper conveyance distance By further comprising a printing speed correction means for creating a quantity, the printing operation speed of the print head is changed in accordance with the conveyance speed of the paper that changes according to the change in the winding diameter of the paper feed roll, Printing conditions can be kept appropriate.

Further, a printing speed correction amount is created during printing of the printing area based on the rotation amount of the paper feed roll and the detected value of the paper transport distance corresponding to the rotation amount of the paper feed roll, and the printing speed correction use amount is corrected printing operation speed of the print head during the period from the completion of printing on the print area to start printing for the next printing region, printing a respective color-in to the same print area Since the printing operation speed of the print head is kept the same during the printing period, the printing speed correction amount created during printing is reflected in the printing of the next printing area, and the time can be shortened. Even when a plurality of colors are overlaid on the printing area, it is possible to eliminate a control error by keeping the printing operation speed constant, and to perform high-quality printing without causing a printing deviation.

According to the present invention described above, to determine the paper speed at the time of printing by the rotation of the sheet feed roller, while stably by conveying the sheet, the rotational speed correction amount for the next printing while performing printing Alternatively, a printing speed correction amount is created, and the correction amount is reflected in the printing of the next printing area, and the rotation speed of the paper feed roll or the printing operation speed of the printing head is made the same for the same printing area. since the holding, while shortening the time, the transport speed of the sheet and printing conditions comprising a printing operation speed of the print head can be kept always the same as the Do Ri, even without using a grip roller having a microprojection accuracy It is possible to provide a printer that can perform printing well.

1 is a schematic diagram illustrating a configuration of a printer according to a first embodiment of the present invention. FIG. 2 is a schematic diagram illustrating an example in which the printer according to FIG. 1 is modified. FIG. 9 is a schematic diagram illustrating a configuration of a printer according to a second embodiment of the invention. FIG. 10 is a schematic diagram illustrating a configuration of a temporary printer using a conventional technique.

Hereinafter, some embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>

  The printer of this embodiment adopts an apparatus configuration as schematically shown in FIG.

  The printer of this embodiment is configured as a thermal transfer type sublimation printer, and the ink ribbon 2 is printed with dyes of each color of Y (yellow), M (magenta), C (cyan), and OP (overcoat). The printing is provided in order corresponding to the size of each region, and printing using these four color dyes is performed individually on the same printing region of the paper 1. A plurality of heating elements (not shown) are arranged side by side on the surface of the print head 3 that is in contact with the paper 1 in a direction perpendicular to the direction in which the paper 1 is conveyed. By energizing in a predetermined pattern, the heating element generates heat, and the dye on the ink ribbon 2 is melted and transferred to the surface of the paper 2. Hereinafter, the transfer of the dye onto the paper 2 by the heat generating action of the individual heat generating elements is generally referred to as a printing operation of the print head 3.

  The printing operation by the print head 3 as described above is performed when the paper 1 is conveyed in a direction (Y direction indicated by an arrow in the drawing) opposite to the paper feeding direction (X direction indicated by an arrow in the drawing). This direction is referred to as a printing direction.

  The paper 1 is pulled out from the paper supply roll 1a in the paper supply direction, and is superposed with the ink ribbon 2 running between the ribbon rolls 2A and 2B, and the print head is elastically contacted with the platen roller 4 and the platen roller 4. 3 is sent to the printing position P formed between the two. The paper 1 is sandwiched between a pair of opposed conveying rollers 21 and 24, and a pass line from the paper feed roll 1a to the printing position P is formed. Here, in the present embodiment, a roller used for transporting the paper 1 is widely referred to as a transport roller regardless of the presence or absence of a drive source. A pulley 21 a is attached to the shaft end of one of the conveying rollers 21, and a driving force from a pulley 22 a attached to the shaft end of the DC motor 22 can be input via a belt 23. In addition, the other transport roller 24 is driven to rotate in accordance with the operation of the sheet 1 that is in contact with it, and since a rotary encoder 41 is attached, a pulse signal corresponding to the rotation amount, that is, the transport distance of the sheet 1 is generated. be able to. The number of pulse signals is counted by the counter 42 and output as the number of pulses. The rotary encoder 41 and the counter 42 function as a transport distance detecting means 6 for detecting the transport distance of the paper 1 in cooperation. The transport roller 24 and the rotary encoder 41 may be a roller-type encoder configured integrally.

  The conveying rollers 21 and 24 have a flat circumferential surface and do not have minute protrusions like the grip roller 521 (see FIG. 4). Therefore, the grip roller 521 (see FIG. 4) does not have a function of gripping the paper 1 and positively imparting a conveyance force, and such a function is given solely by a paper feed roll 1a described below. .

A paper feed roll driving means 5 for rotating the paper feed roll 1a is provided. The paper feed roll driving means 5 includes a pulley 11 provided at a shaft end portion of a mounting shaft (not shown) to which the paper feed roll 1 a is attached and rotates integrally, and a stepping that applies a driving force to the pulley 11 via a belt 13. and a pulley 12 a provided in the motor 12 and its axis. As the stepping motor 12, I coupled with a reduction ratio by the pulley 11, 12 a, only the drive provided sufficiently large conveying force to the sheet 1 as compared with the frictional resistance or the like generated in the sheet 1 during printing What has torque is used, and can be driven without being stepped out regardless of the winding diameter of the paper feed roll 1a. Therefore, the conveyance speed and conveyance distance of the paper 1 can be accurately controlled by controlling the rotation amount of the sheet feeding roll 1a.

  The ink ribbon 2 is unwound from the supply-side ribbon roll 2B, and the Y, M, C, and OP color areas are used according to printing while the pass lines are defined by the guide rollers 25a and 25b, and then the winding side. It is wound up by the ribbon roll 2A. In the printer according to the present embodiment, prior to printing of each color, the color area of the ink ribbon 2 is determined by a sensor (not shown), and the position control is performed so that the leading position of each color area can be matched with the printing position P. During operation, the ink ribbon 2 can be conveyed from the supply side ribbon roll 2B to the take-up side ribbon roll 2A in conjunction with the conveyance of the paper 1.

  The paper 1 on which each color has been printed is conveyed in the X direction, cut by a cutter unit (not shown), and then discharged to the outside of the printer.

  Control of each unit is performed on the apparatus having the above basic configuration by a system including the following control blocks.

  First, the print command unit 31 creates a reference command for printing a target image, and outputs the reference command to the rotation pattern setting unit 32 and the printing operation pattern setting unit 35. The rotation pattern setting unit 32 sets the rotation pattern of the paper feed roll 1a based on the reference command. That is, based on a given reference command, a rotation pattern including a rotation start timing, a rotation amount, a rotation speed, and the like for synchronizing with the operation of the print head 3 is set and output to the stepping motor control unit 33. The stepping motor control unit 33 gives a control command to the stepping motor 12 according to the input rotation pattern to drive the paper feed roll 1a.

  On the other hand, the printing operation pattern setting unit 35 sets a printing operation pattern for controlling the printing operation of the printing head 3 based on the reference command. That is, a print operation start timing for synchronizing with the rotation of the paper feed roll 1 a and a print operation pattern including a heat generation pattern for each line are set and output to the print head controller 36. The print head controller 36 generates heat by energizing each heating element of the print head 3 in accordance with the input printing operation pattern.

  With the configuration described above, printing can be performed by causing each heating element of the print head 3 to generate heat while transporting the paper 1, but the paper feed roll 1 a has a winding diameter each time the paper 1 is used. In order to decrease (refer to the pass lines 1A and 1B in the figure), the peripheral speed decreases and the conveyance speed of the paper 1 decreases when rotating at the same rotational speed. Therefore, the relative relationship with the printing operation in the print head 3 changes, and different printing results are generated even for the same image. Specifically, the conveyance speed of the paper 1 is reduced with respect to the change speed of the energization pattern applied to each heating element of the print head 3, that is, the printing operation speed of the print head 3, and the form compressed in the printing direction. Printing will be performed.

  In order to solve this problem, in this embodiment, the printing operation of the print head 3 is performed by suppressing the change in the peripheral speed and keeping the paper speed substantially the same by performing the speed correction with the change in the winding diameter of the paper feed roll 1a. The relative relationship with the speed is kept the same.

  Specifically, the rotation amount of the paper feed roll 1a determined by the rotation pattern setting unit 32 and the paper 1 detected by the transport distance detection means 6 while the paper feed roll 1a is rotating according to the control. The conveyance distance is input to the rotation speed correction unit 34, and the rotation speed correction unit 34 creates a rotation speed correction amount for canceling the winding diameter change of the paper feed roll 1 a, and outputs it to the rotation pattern setting unit 32. I am doing so. The rotation pattern setting unit 32 is configured to correct the rotation speed command value of the stepping motor 12 in accordance with the value when the rotation speed correction amount is input and output the correction value to the stepping motor control unit 33. It is.

The above correction is performed based on the relationship as follows. In order to simplify the explanation, the number of pulse signals as a command value for the stepping motor 33 and the count value of the pulse signal from the encoder 41 are respectively set for the rotation amounts (number of rotations) of the paper feed roll 1 a and the transport roller 24. In terms of conversion, the relationship is as follows.
L1 = π · d · n1 = π · D1 · N1 Equation (1)

Here, D1 is the winding diameter (outer diameter) of the paper feed roll 1a at time t1, N1 is the rotation amount of the paper feed roll 1a set immediately before t1, d is the outer diameter of the transport roller 24, and n1 is the paper feed roll. The rotation amount of the conveyance roller 24 detected while 1a rotates N1 and L1 indicates the conveyance distance of the sheet 1 while the sheet feeding roll 1a rotates N1. When this mathematical formula (1) is transformed, the winding diameter D1 is calculated as in the following formula.
D1 = d · (n1 / N1) ……………………… Formula (2)

  When the winding diameter of the sheet feeding roll 1a is D1, the peripheral speed is D1 / D0 times that of the reference winding diameter D0. Therefore, when correcting the peripheral speed to be constant, the rotational speed should be corrected to D0 / D1 times using the above equation.

  In the present embodiment, the rotational speed correction means 34 calculates the rotational speed correction amount based on the input values from the rotational pattern measurement section 32 and the counter 42 using the above-described concept, and the rotational pattern measurement section. 32 is configured to feed back.

  The printer according to the present embodiment configured with the apparatus and the control system as described above specifically operates as follows.

When the printer is activated, the end E of the paper 1 is detected and aligned by an end detection sensor (not shown), and then the stepping motor 12 is rotated by a predetermined amount of rotation to wind the paper 1 in the Y direction. return. At this time, the transport roller 21 is not driven and is driven with respect to the paper 1 and is actually determined from the number of pulses obtained from the encoder 41 and the counter 42 as the transport distance detecting means 6 provided on the transport roller 24 facing the transport roller 24. The transport distance is detected. Then, the roll diameter of the paper feed roll 1a is calculated by the rotational speed correction means 34 from the rotation amount of the paper feed roll 1a and the transport distance of the paper 1. If the winding diameter is different from the reference winding diameter D0, it is output as a correction command to the rotation pattern setting section 32 in order to correct the rotation speed during printing.

  In this way, after the rotation speed at the time of printing is optimized, the paper 1 is sent out by rotating the paper feed roll 1a until the edge E of the paper 1 reaches the edge detection sensor position again. At this time, the transport roller 21 is driven by the DC motor 22 and the paper 1 is fed in the paper feeding direction without slack. After the end E reaches the sensor position, the paper feed roll 1a is rewound so as to obtain a predetermined transport distance in terms of the winding diameter corrected as described above, and the print start position S is set to the print position P. To match. Also at this time, the transport roller 21 is driven.

Thereafter, in consideration of the rotational speed correction amount based on the winding diameter obtained by the above calculation, the conveyance speed of the paper 1 at the time of printing is substantially constant between the printing regions regardless of the change in the winding diameter of the paper feed roll 1a. Thus, the rotational speed of the paper feed roll 1a is determined, and printing of each color of Y, M, C, and OP is performed by the print head 3 while conveying the paper 1 at the rotational speed. During printing of each color, the paper feed roll 1a is driven at a constant rotational speed and the transport rollers 21 and 24 are driven as described above, so the transport speed of the paper 1 is the peripheral speed of the paper feed roll 1a. Determined by. After first printing Y (yellow) on the printing area and before printing M (magenta), the paper feed roll 1a is reversely rotated by the same amount and the transport roller 21 is driven. Then, the printing start position S of the paper 1 is adjusted to the printing position P again, and printing of M (magenta) is started. In this way, a target print image can be obtained by repeatedly printing each color on the same print region.

Further, while printing each color on the same printing area, the rotation speed correction means 34 newly supplies the feed speed from the rotation amount of the paper feed roll 1a and the conveyance distance detected by the conveyance distance detection means 6. The roll diameter of the paper roll 1a is calculated to create a rotation speed correction amount command value. The rotation speed correction amount uses the same value until printing for the same print area is completed, but is output to the rotation pattern setting unit 32 after printing is completed, and is prepared for printing such as alignment for the next print area. This is reflected in the rotation speed of the paper feed roll 1a from the stage.

  In this way, by updating the rotational speed correction amount in accordance with the change in the winding diameter of the paper feed roll 1a for each printing region, the transport speed of the paper 1 during printing can be made substantially the same. Therefore, the relative relationship between the conveyance speed of the paper 1 and the printing operation of the print head 3 can be kept the same, and high quality printing can always be performed. In addition, since the same rotation speed correction amount is maintained for the same print area, even if the paper 1 is repeatedly conveyed in the paper feeding direction and the printing direction, the print position of each color is shifted due to a detection error. Is prevented from occurring. Furthermore, it is possible to reduce the time required for setting the correction amount by performing detection of the conveyance distance for creating the rotation speed correction amount at the same time as printing other than at the time of activation.

  As described above, the printer according to the present embodiment inks the paper 1 fed from the paper feed roll 1a at the printing position P set between the platen roller 4 and the print head 3 that is elastically contacted with the platen roller 4. In order to drive the paper feed roll 1a, printing is performed by giving a signal from the print head control unit 36 to the print head 3 to perform a printing operation while feeding the ribbon 2 in a superposed state. The paper feed roll driving means 5 is provided, and the rotational speed of the paper feed roll 1a driven by the paper feed roll drive means 5 is configured to define the transport speed of the paper 1 at the printing position. The speed correction for printing while maintaining the same relative relationship between the conveyance speed and the printing operation speed of the print head 3 is performed by the rotation speed of the paper feed roll 1a. Those were.

  With this configuration, the conveyance speed of the paper 1 during printing is determined by the paper feed roll 1a, and the relationship between the conveyance speed of the paper 1 being printed and the printing operation speed of the print head 3 is kept the same. Since appropriate printing conditions can be maintained, high-quality printing can be performed with high accuracy without using the grip roller 521 (see FIG. 4) having minute protrusions.

  Further, a transport distance detecting means 6 for detecting a transport distance of the paper 1 transported while the paper feed roll 1a rotates by a predetermined amount, a rotation amount of the paper feed roll 1a, and a rotation of the paper feed roll 1a Rotational speed correction means 34 for correcting the rotational speed during printing of the paper feed roll 1a based on the detected value of the transport distance of the paper 1 corresponding to the amount so that the transport speed of the paper 1 is substantially constant. Since it is configured to be provided, by correcting the rotation speed of the paper feed roll 1a according to the change in the winding diameter of the paper feed roll 1a that can be grasped by the rotation amount of the paper feed roll 1a and the transport distance of the paper 1, Since the conveyance speed of the paper 1 can be kept substantially constant during printing, high-quality printing can always be performed while maintaining appropriate printing conditions.

Further, based on the rotation amount of the paper feed roll 1a at the time of printing and the detected value of the transport distance of the paper 1 corresponding to the rotation amount of the paper feed roll 1a, before the start of printing for the next print area, While the rotational speed of the paper feed roll 1a is corrected and the rotational speed of the paper feed roll 1a is kept the same during printing on the same printing area, By creating a rotational speed correction amount for the next printing and reflecting the correction amount at the start of the next printing, the time can be reduced and printing can be performed under conditions that always have few errors. Even when multiple colors are printed in the same print area, since the rotation speed is kept constant, no control error occurs, so there is no print misalignment. Quality printing can be performed.
<Modification>

  The first embodiment described above can be used by being modified to the form schematically shown in FIG. The same parts as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  In this modification, a DC motor 112 is used as a general motor as a drive source of the drive means 105 of the paper feed roll 1a. In this case, in order to determine the number of rotations of the motor 112, an encoder 143 that detects the amount of rotation of the pulley 112a is provided, and the motor control unit 133 increases the number of pulses generated from the encoder 143 and the number of pulses. While monitoring the speed, the motor 112 is controlled so that the rotation amount and the rotation speed of the paper feed roll 1 a match the rotation pattern set by the rotation pattern setting unit 32.

As described above, even if the driving unit 105 is configured, the rotation speed of the paper feed roll can be corrected in the same manner as in the case shown in FIG. 1, and the same effect as described above can be obtained.
Second Embodiment

  The printer of this embodiment employs an apparatus configuration as schematically shown in FIG. In the figure, parts that are the same as those in FIG.

  In the printer of this embodiment, in order to keep the relative relationship between the conveyance speed of the paper 1 and the printing operation of the print head 3, it changes with the change in the winding diameter without changing the rotation speed of the paper feed roll 1 a. Speed correction corresponding to the transport speed of the paper 1 to be performed is performed on the printing operation speed of the print head 3.

For this purpose, the rotation amount of the paper feed roll 1a obtained from the rotation pattern setting unit 232 and the conveyance distance obtained by the conveyance distance detection means 6 at that time are input to the printing speed correction means 237, and the printing speed correction means A printing speed correction amount for changing the printing operation pattern is created and output to the printing operation pattern setting unit 235. The print operation pattern setting unit 235 creates a print operation pattern in which the change rate of energization of a heating element (not shown) included in the print head 3 and the energization amount per unit time are changed according to the correction amount, and the print head Output to the control unit 36, and a specific energization to the print head 3 is performed by the print head control unit 36 in accordance with the printing operation pattern.

  Such a correction amount of the printing operation speed is generated at the time of starting up the printer and at the time of printing, as in the case of the first embodiment. Then, by reflecting the printing speed correction amount before printing on the next printing area is started, it is possible to obtain a printing operation speed in accordance with a change in the winding diameter of the paper feed roll 1a.

  Since the relative relationship between the paper speed and the printing operation of the print head 3 can be kept the same by changing the printing operation speed in this way, the printing conditions are appropriately set as in the first embodiment. You can always keep high quality printing.

  As described above, the printer according to the present embodiment inks the paper 1 fed from the paper feed roll 1a at the printing position P set between the platen roller 4 and the print head 3 that is elastically contacted with the platen roller 4. In order to drive the paper feed roll 1a, printing is performed by giving a signal from the print head control unit 36 to the print head 3 to perform a printing operation while feeding the ribbon 2 in a superposed state. The paper feed roll driving means 5 is provided, and the rotational speed of the paper feed roll 1a driven by the paper feed roll drive means 5 is configured to define the transport speed of the paper 1 at the printing position. Speed correction for printing is performed on the printing operation speed of the print head 3 while keeping the relative relationship between the conveyance speed and the printing operation speed of the printing head 3 the same. It is obtained by sea urchin configuration.

  With this configuration, as in the first embodiment, the conveyance speed of the paper 1 during printing is determined by the paper feed roll 1a while the conveyance speed of the paper 1 being printed and the print head 3 Since the relationship with the printing operation speed can be kept the same and appropriate printing conditions can be maintained, high-quality printing can be accurately performed without using the grip roller 521 (see FIG. 4) having minute protrusions. be able to.

  Further, a transport distance detecting means 6 for detecting a transport distance of the paper 1 transported while the paper feed roll 1a rotates by a predetermined amount, a rotation amount of the paper feed roll 1a, and a rotation of the paper feed roll 1a Since it is configured to include a printing speed correction unit 237 that corrects the printing operation speed of the print head 3 based on the detected value of the conveyance distance of the paper 1 corresponding to the amount, the winding diameter of the paper feed roll 1a The printing operation speed can be changed in accordance with the conveyance speed of the paper 1 during printing, and the relative relationship between the two can be kept the same, so that high quality printing is always performed. be able to.

  Further, based on the rotation amount of the paper feed roll 1a at the time of printing and the detected value of the transport distance of the paper 1 corresponding to the rotation amount of the paper feed roll 1a, the printing before the start of printing for the next printing area is performed. The print operation speed of the print head 3 is corrected so as to correspond to the change in the conveyance speed of the paper 1, and the print operation speed of the print head 3 is kept the same while printing on the same print area. Because it is configured, a rotational speed correction amount is created for the next printing while printing is performed, and the correction amount is reflected at the start of the next printing, thereby shortening the time and always providing an error. It is possible to perform printing under a small amount of conditions. In addition, even when a plurality of colors are overlaid on the same printing area, since the printing operation speed is kept constant, no control error occurs, so that there is no printing misalignment. High quality printing can be performed.

  The specific configuration of each unit is not limited to the above-described embodiment.

  For example, in the first embodiment and the second embodiment described above, in order to keep the relative relationship between the paper transport speed and the print operation speed of the print head, correction is made for one of the speeds. Without adding, only the other speed is corrected so that the relative relationship between the two is the same, but as long as the relative relationship between the two can be the same, both should be corrected. And the same effect as above can be obtained.

In the first embodiment and the second embodiment described above, until the printing on the same printing area is completed, by using the same value of the rotational speed correction amount or print speed correction amount The relative relationship between the conveyance speed of the paper 1 during printing and the printing operation of the print head 3 is not changed. Instead of such a method, it is possible to continuously correct the rotation speed or the printing operation speed in real time by constantly monitoring the conveyance speed of the conveyance roller 24 and the rotation speed of the paper feed roll 1a during printing. However, when a slight slip occurs between the transport roller 24 and the paper 1 due to external factors such as vibration during printing, there is a possibility that the printing position of each color may be shifted, as in the above embodiment. It is preferable to perform correction for each printing area and use the same correction amount until printing in the same printing area is completed.

  Other configurations can be variously modified without departing from the spirit of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Paper 1a ... Paper feed roll 2 ... Ink ribbon 3 ... Print head 4 ... Platen roller 5 ... Paper feed roll drive means 6 ... Conveyance distance detection means 12 ... Stepping motor 21 ... Conveyance roller 22 ... Motor 24 ... Conveyance roller 31 ... Print command section 32 ... Rotation pattern setting section 33 ... Stepping motor control section 34 ... Rotation speed correction means 35 ... Print operation pattern setting section 36 ... Print head control section 41 ... Encoder 42 ... Counter 237 ... Print speed correction means

Claims (2)

In a state where the paper fed out from the paper feed roll is superposed on an ink ribbon in which a plurality of color dyes are provided in order at a printing position set between the platen roller and the print head that is elastically contacted with the platen roller. feeding while printing operations and which Ru gives a signal from the print head control unit to the printing head, by repeating the operation in which reversely rotates the feed roll, a printer for performing individual printing of each color for the same print area Because
A paper feed roll driving means for driving the paper feed roll, and the rotational speed of the paper feed roll driven by the paper feed roll drive means is configured to define the paper conveyance speed at the printing position; A conveyance distance detecting means for detecting a conveyance distance of a sheet conveyed while the sheet feeding roll rotates by a predetermined amount; a rotation amount of the sheet feeding roll and a rotation amount of the sheet corresponding to the rotation amount of the sheet feeding roll; Based on the detection value of the conveyance distance, the rotation speed at the time of printing of the paper feed roll is corrected so that the paper conveyance speed is substantially constant between the printing regions regardless of the change in the winding diameter of the paper feed roll. Rotational speed correction means for creating a rotational speed correction amount for
The rotational speed correction amount is created based on the detected value of the paper feed distance corresponding to the rotation amount of the paper feed roll and the rotation amount of the paper feed roll during printing of the print area, and the rotational speed correction amount During the period from the completion of printing to the printing area to the start of printing to the next printing area, the rotation speed of the paper feed roll is corrected and printing of each color is performed on the same printing area. by keeping the rotational speed of the feed roll to the same printer, wherein the benzalkonium be printed while maintaining the relationship between the conveying speed of the sheet and the printing operation speed of the print head in the same. In a state where the paper fed out from the paper feed roll is superposed on an ink ribbon in which a plurality of color dyes are provided in order at a printing position set between the platen roller and the print head that is elastically contacted with the platen roller. feeding while printing operations and which Ru gives a signal from the print head control unit to the printing head, by repeating the operation in which reversely rotates the feed roll, a printer for performing individual printing of each color for the same print area Because
A paper feed roll driving means for driving the paper feed roll, and the rotational speed of the paper feed roll driven by the paper feed roll drive means is configured to define the paper conveyance speed at the printing position; A conveyance distance detecting means for detecting a conveyance distance of a sheet conveyed while the sheet feeding roll rotates by a predetermined amount; a rotation amount of the sheet feeding roll and a rotation amount of the sheet corresponding to the rotation amount of the sheet feeding roll; Based on the detection value of the conveyance distance, a printing speed correction amount for correcting the printing operation speed of the print head so as to correspond to the change in the conveyance speed of the paper accompanying the change in the winding diameter of the paper feed roll is created. And a printing speed correction means for
During printing in the printing area, a printing speed correction amount is created based on the rotation amount of the paper feed roll and the detected value of the paper transport distance corresponding to the rotation amount of the paper feed roll, and the printing speed correction amount is set. The printing operation speed of the print head is corrected during the period from the completion of printing for the printing area to the start of printing for the next printing area, and during the printing of each color for the same printing area by holding the printing operation speed of the print head in the same printer, wherein the benzalkonium be printed while maintaining the relationship between the conveying speed of the sheet and the printing operation speed of the print head in the same.

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