JP2022155801A - Printing system and printing method - Google Patents

Abstract

A printing system and a printing method capable of accurately correcting set values relating to transport of an ink ribbon are provided.
A printing system includes a printing device and a controller. A printing device includes a thermal head, a first spool, a second spool, a first motor, a second motor, a guide shaft, and an encoder. A first spool carries a supply roll and is driven by a first motor to rotate. A second spool has a winding roll mounted thereon and is driven by a second motor to rotate. The guide shaft rotates as the ink ribbon is transported. The encoder detects the amount of rotation of the guide shaft. The controller performs printing with the thermal head (S22). The controller then conveys the ink ribbon from the supply roll to the take-up roll (S31). The transport amount of the ink ribbon at this time is larger than the amount used in printing. The controller measures the transport amount and transport speed of the ink ribbon (S32). The controller corrects the diameters of the supply roll and the take-up roll (S41).
[Selection drawing] Fig. 7

Description

The present invention relates to a printing system and printing method.

A recording apparatus including the conveying device of Patent Document 1 includes a roller for conveying a sheet, an opposing roller that faces the roller, and a drive motor that drives the roller. Based on the rotation speed of the roller and the driving current of the motor, the conveying device controls the operation of the drive motor during the period when the sheet is conveyed by a predetermined conveying amount from the position where the edge of the sheet enters the nipping portion between the roller and the opposing roller. Work is determined, and sheet dimensions are determined based on the work.

JP 2018-144904 A

When the distance that the sheet is conveyed is short, the amount of rotation of the roller and the drive current of the drive motor are small. Therefore, the conveying device cannot accurately detect the rotational speed of the roller and the driving current of the driving motor, and cannot accurately obtain the dimensions of the sheet. If the dimensions of the sheet obtained by the conveying device differ from the actual dimensions of the sheet to be conveyed, the conditions for conveying the sheet will be inappropriate, which may cause an image defect when the recording device records an image on the sheet. be.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a printing system and a printing method capable of accurately correcting set values relating to transport of an ink ribbon.

A printing system according to a first aspect of the present invention includes a printing device and a control unit, wherein the printing device includes a thermal head and a mechanism for conveying an ink ribbon, and is capable of supplying the ink ribbon to the thermal head. a supply section, a receiving section provided on the opposite side of the thermal head to the supply section and capable of receiving the ink ribbon, and driven by the ink ribbon transported between the supply section and the reception section. a conveying mechanism having a roller rotatable as a roller; and a detection unit that detects the amount of rotation of the roller. A printing process and a process in which the transport mechanism transports the ink ribbon from the supply unit to the receiving unit, wherein the first transport mechanism transports the ink ribbon a second distance longer than the first distance used in the printing process. a transporting process including a transporting process; a measuring process for measuring at least one of a transporting speed and a transporting length of the ink ribbon transported in the transporting process based on the detection result of the detecting unit; and a measurement in the measuring process. and a correction process for correcting a set value relating to transport of the ink ribbon by the transport mechanism based on the result.

According to the above configuration, the printing system conveys the ink ribbon for the second distance longer than the first distance used for the printing process in the conveying process. Since the distance for conveying the ink ribbon is increased, the detection accuracy of the detection unit is increased. Therefore, the printing system can correctly correct the setting value related to the transportation of the ink ribbon.

In the printing system of the first aspect, the control section may perform a pull-back process in which the transport mechanism pulls back the ink ribbon to the supply section after the first transport process. The printing system pulls back the ink ribbon, which has been transported a second distance longer than the first distance used for the printing process in the first transporting process, to the supply unit side. Therefore, the printing system can prevent the distance over which the ink ribbon is conveyed from becoming excessive.

In the printing system of the first aspect, the correction processing may correct, as the set value, the amount of the ink ribbon in at least one of the supply section and the reception section. The printing system corrects the amount of ink ribbon in at least one of the supply section and the receiving section as a set value. Therefore, the printing system can correctly correct the amount of the ink ribbon and convey it.

In the printing system of the first aspect, the printing device may include a stepping motor that drives a conveying device, and the correction process may correct a driving signal of the stepping motor as the set value. The printing system corrects the drive signal of the stepping motor as the set value. Therefore, the printing system can correctly correct the drive signal of the stepping motor and convey the paper.

In the printing system according to the first aspect, the control section can execute a second conveying process in which the conveying mechanism conveys the ink ribbon of the first distance from the supplying section to the receiving section in the conveying process. , according to the first distance, either one of the first transport process and the second transport process may be switched and executed. The printing system switches between the first transporting process and the second transporting process of transporting the ink ribbon for the first distance as appropriate. Therefore, the printing system can prevent the distance over which the ink ribbon is transported from becoming excessive in the transport process.

In the printing system of the first aspect, the control unit, when executing the second conveying process, sets a predetermined first speed and a second speed slower than the first speed according to the first distance. The ink ribbon may be conveyed by either one. The printing system transports the ink ribbon at one of the first speed and the second speed, which is slower than the first speed, in the second transport process. When the ink ribbon is conveyed at the second speed, the slippage of the ink ribbon on the roller is reduced, and the detection accuracy of the detection unit is increased. Therefore, the printing system can correctly correct the setting value related to the transportation of the ink ribbon.

In the printing system according to the first aspect, the printing device includes a head motor that moves at least in a first direction parallel to the transport direction of the ink ribbon facing the thermal head, and the control unit, in the printing process, Printing may be performed by heating the thermal head while moving the thermal head in the first direction by the head motor while the transportation of the ink ribbon in the transportation process is temporarily stopped. In the printing system, when the ink ribbon is transported intermittently, the detection accuracy of the detection unit is improved. Therefore, the printing system can correctly correct the setting value related to the transportation of the ink ribbon.

A printing method according to a second aspect of the present invention includes a thermal head, a mechanism for conveying an ink ribbon, a supply section capable of supplying the ink ribbon to the thermal head, and the supply section for the thermal head. a conveying mechanism provided on the opposite side of the ink ribbon and having a receiving portion capable of receiving the ink ribbon; and a roller rotatable following the ink ribbon conveyed between the supplying portion and the receiving portion; A printing method using a printing apparatus including a detection unit that detects the amount of rotation of the roller, wherein the thermal head heats the ink ribbon to print on a print medium, and the conveying mechanism transfers the ink. a conveying step of conveying the ribbon from the supply portion to the receiving portion, the conveying step including a first conveying step of conveying the ink ribbon a second distance longer than the first distance used in the printing step; a measuring step of measuring at least one of a transport speed and a transport length of the ink ribbon transported in the transporting step based on the detection result of the ink ribbon; and a correction step of correcting a set value related to ribbon transport. The printing method of the second aspect can produce the same effect as the first aspect.

1 is a diagram showing an overview of a printing system 8; FIG. 2 is a block diagram showing an electrical configuration of a printing system 8; FIG. 8A and 8B are diagrams for explaining the printing operation of the printing system 8 when the ink ribbon 9 is conveyed in patterns Q1 and Q2 in the conveying process; FIG. FIG. 10 is a diagram for explaining the printing operation of the printing system 8 when the ink ribbon 9 is transported in the pattern Q3 in the transport process; 4 is a graph showing temporal variations in the transport speed of the ink ribbon 9 in the transport process. 4 is a flowchart of main processing; FIG. 7 is a flowchart of a main process continued from FIG. 6; FIG.

<Overview of Printing System 8>
An embodiment of the present invention will be described with reference to the drawings. The printing system 8 is a system for performing thermal transfer printing. The printing system 8 prints on a printing medium P transported by an external device 100 (see FIG. 2). A specific example of the external device 100 is a packaging machine that conveys packaging materials. In this case, for example, the printing system 8 is used by being incorporated into a part of a transport line along which the printing medium P is transported by the packaging machine.

As shown in FIG. 1, the printing system 8 includes a printing apparatus 1, control units 7 and 111 (see FIG. 2), a platen 20, and an inter-device controller 110 (see FIG. 2). Below, the upper side, the lower side, the left side, the right side, the front side, and the rear side of the printing apparatus 1 are defined in order to facilitate understanding of the explanation of the drawings. The upper, lower, left, right, front, and rear sides of the printing apparatus 1 correspond to the upper, lower, left, right, front, and back sides in FIG. 1, respectively. In FIG. 1 , the transport direction of the print medium P coincides with the horizontal direction of the printing apparatus 1 . The print medium P is conveyed from right to left by the external device 100 .

The printing apparatus 1 is a thermal transfer type thermal printer. The printing device 1 includes a thermal head 3, and a first motor 81, a second motor 82, a third motor 83, and a fourth motor 84 (see FIG. 2). As shown in FIG. 1, the printing device 1 has a box-shaped housing 10 . A substrate 10A is fixed inside the housing 10 . A thermal head 3, a controller 7 (see FIG. 2), and a transport mechanism 6 are provided on the substrate 10A. The conveying mechanism 6 includes a ribbon mounting portion 2, a guide shaft 60, and a motor 80 (see FIG. 2). The guide shaft 60 is a general term for the guide shafts 61 , 62 , 65 and 66 . A motor 80 is a general term for a first motor 81, a second motor 82, a third motor 83, and a fourth motor 84.

A flat platen 20 is arranged below the printing apparatus 1 . The thermal head 3 and the platen 20 face each other in the vertical direction. A first motor 81 and a second motor 82 (see FIG. 2) transport the ink ribbon 9 between the thermal head 3 and the platen 20 . The printing device 1 is adjacent to the printing medium P with the lower end of the printing device 1 facing the printing surface of the printing medium P (the upper surface in FIG. 1). A print medium P transported by the external device 100 passes between the ink ribbon 9 and the platen 20 . That is, the platen 20 is arranged opposite to the ink ribbon 9 with respect to the transport path of the print medium P transported by the external device 100 .

<Ribbon assembly 90>
The printing apparatus 1 prints on the printing medium P by heating the ink ribbon 9 of the ribbon assembly 90 housed inside the housing 10 with the thermal head 3 . The ribbon assembly 90 has core shafts 90A and 90B and an ink ribbon 9 . The core shafts 90A and 90B are each cylindrical. The ink ribbon 9 is a strip-shaped film, and an ink layer is applied to the surface of a base material such as polyethylene terephthalate (PET). The ink layer includes, for example, a pigment component such as carbon and a binder component such as wax and/or resin. The ink is melted by heating and transferred to the print medium P. The ink ribbon 9 may have functional layers such as a back coat layer, a peeling layer, and an adhesive layer, if necessary. The ink ribbon 9 has one end connected to the side surface of the core shaft 90A and the other end connected to the side surface of the core shaft 90B.

The ribbon assembly 90 is attached to the ribbon attachment portion 2 of the printing apparatus 1 with the ink ribbon 9 wound around the core shaft 90A. The ink ribbon 9 wound around the core shaft 90A is called a "supply roll 9A." In the process of printing by the thermal head 3, the ink ribbon 9 is let out from the supply roll 9A of the core shaft 90A, guided by the guide shaft 60 and the thermal head 3, and wound around the core shaft 90B. The ink ribbon 9 wound around the core shaft 90B is called a "winding roll 9B".

<Ribbon attachment part 2>
The ribbon mounting section 2 has a first motor 81 , a second motor 82 , a first spool 21 and a second spool 22 . The first spool 21 and the second spool 22 are each rotatable around a rotation axis extending in the front-rear direction. The first spool 21 is provided substantially in the center of the substrate 10A in the vertical direction and on the right side of the center in the horizontal direction. The second spool 22 is provided substantially in the center of the substrate 10A in the vertical direction and on the left side of the center in the horizontal direction. A supply roll 9A wound around a core shaft 90A of a ribbon assembly 90 is attached to the first spool 21 . A winding roll 9B wound around the core shaft 90B of the ribbon assembly 90 is attached to the second spool 22 .

The first spool 21 is directly connected to a first motor 81 (see FIG. 2) and rotated by the first motor 81 . The second spool 22 is directly connected to a second motor 82 (see FIG. 2) and rotated by the second motor 82 . Since the first spool 21 and the second spool 22 are rotated by different motors 80, they can rotate at different rotational speeds. The first spool 21 and the second spool 22 may be indirectly connected to the first motor 81 and the second motor 82, respectively.

When the first spool 21 and the second spool 22 rotate counterclockwise when the printer 1 in FIG. 1 is viewed from the front side, the core shafts 90A and 90B rotate in the normal direction. At this time, the ink ribbon 9 is let out from the supply roll 9A and wound on the take-up roll 9B. When the first spool 21 and the second spool 22 rotate clockwise when the printer 1 in FIG. 1 is viewed from the front side, the core shafts 90A and 90B rotate in the reverse direction. The ink ribbon 9 is unwound from a take-up roll 9B and taken up by a supply roll 9A.

The ink ribbon 9 stretched between the supply roll 9A and the take-up roll 9B is conveyed within the housing 10 as the first spool 21 and the second spool 22 rotate. A route through which the ink ribbon 9 is conveyed is called a “conveyance route R”. The ink ribbon 9 is transported and guided along the transport path R by contacting the guide shaft 60 . The thermal head 3 is adjacent to the ink ribbon 9 stretched between the supply roll 9A and the take-up roll 9B.

<Thermal head 3>
The thermal head 3 is provided below the first spool 21 and the second spool 22 on the front surface of the substrate 10A. The thermal head 3 is provided partly in the direction in which the ink ribbon 9 is conveyed. The thermal head 3 has a plurality of heating elements linearly arranged in the front-rear direction. The front-rear direction is the direction corresponding to the width direction of the ink ribbon 9, which is the direction intersecting the conveying direction of the ink ribbon 9. As shown in FIG. The thermal head 3 performs printing using the ink ribbon 9 by causing a plurality of heating elements arranged in the width direction of the ink ribbon 9 to generate heat.

The thermal head 3 can move vertically and horizontally. The third motor 83 (see FIG. 2) vertically moves the thermal head 3 between the head positions 3A and 3B. The head position 3B is a position where the ink ribbon 9 is urged toward the platen 20. FIG. The head position 3A is a position above the head position 3B and away from the ink ribbon 9 to release the biasing force of the ink ribbon 9 against the platen 20 . That is, the third motor 83 moves the thermal head 3 toward and away from the platen 20 . The fourth motor 84 (see FIG. 2) moves left and right. The position of the right end of the movable range of the thermal head 3 in the left-right direction is called the standby position.

<Guide shaft 60>
The guide shaft 60 has a cylindrical shape and extends forward from the front surface, which is the surface of the substrate 10A. The guide shaft 60 is rotatable around a rotation axis extending in the front-rear direction. The guide shaft 61 is provided near the upper right corner of the substrate 10A. The guide shaft 62 is provided near the lower right corner of the substrate 10A. The guide shaft 65 is provided near the lower left corner of the substrate 10A. A guide shaft 66 is provided near the upper left corner of the substrate 10A.

The ink ribbon 9 contacts part of the peripheral surface of the guide shaft 60 . The transport path R of the ink ribbon 9 extends obliquely upward to the right from the supply roll 9A mounted on the first spool 21, contacts the guide shaft 61, changes direction, and extends downward toward the guide shaft 62. , changes direction in contact with the guide shaft 62 and extends leftward toward the guide shaft 65 . The direction of the transport path R of the ink ribbon 9 is changed according to contact with the thermal head 3 in the middle portion between the guide shafts 62 and 65 . The conveying path R of the ink ribbon 9 further contacts the guide shaft 65 to change direction, extends upward toward the guide shaft 66, contacts the guide shaft 66 to change direction, and extends rightward toward the take-up roll 9B. It extends obliquely downward. Note that the printer 1 may be provided with another guide shaft that changes the direction of the transport path R, for example, between the guide shaft 62 and the guide shaft 65 .

<Electrical Configuration of Printing System 8>
The electrical configuration of the printing system 8 will be described with reference to FIG. The printing device 1 has a control section 7 . The control unit 7 is composed of, for example, a CPU that controls the printing apparatus 1 and various drive circuits that operate according to instructions from the CPU. Various drive circuits include, for example, a circuit for supplying signals (for example, drive current) to the first motor 81, the second motor 82, the third motor 83, and the fourth motor 84, which are the motors 80; It includes circuitry for providing signals (eg, drive currents), and the like. The control unit 7 includes a storage unit 71, an operation unit 73, the thermal head 3, a first motor 81, a second motor 82, a third motor 83, a fourth motor 84, an encoder 811, and a communication unit. It is electrically connected to an interface (communication I/F) 72 via an interface circuit (not shown).

The thermal head 3 generates heat according to a signal output from the controller 7 . A motor 80 is a stepping motor that rotates in synchronization with a pulse signal. The first motor 81 rotates the first spool 21 according to the pulse signal output from the controller 7 . The second motor 82 rotates the second spool 22 according to the pulse signal output from the controller 7 . The third motor 83 rotates according to the pulse signal output from the control section 7 to move the thermal head 3 vertically. The fourth motor 84 rotates according to the pulse signal output from the control section 7 to move the thermal head 3 in the horizontal direction.

An encoder 811 detects the rotational position and amount of rotation of the guide shaft 65 . The encoder 811 outputs a signal indicating the detected rotational position and amount of rotation to the control section 7 . Communication I/F 72 is an interface element for communicating with inter-device controller 110 .

The inter-device controller 110 is provided outside the printing device 1 and controls communication between the printing device 1 and an external device. The inter-device controller 110 includes a control section 111 , a storage section 112 , a communication I/F 113 and a communication I/F 114 . The communication I/F 113 is connected to the communication I/F 72 of the printing apparatus 1 by wire or wirelessly. The communication I/F 114 is wired or wirelessly connected to the external device 100 and the external terminal 150 that are external devices. In this embodiment, the external device 100 is a device that conveys the print medium P (for example, a packaging machine that conveys packaging materials). The external terminal 150 is a terminal (for example, a PC) that allows the user to give various instructions to the printing apparatus 1 .

The storage unit 71 of the printing device 1 includes various storage media such as ROM, RAM, and flash memory. The storage unit 71 stores programs for processing executed by the control unit 7 . The storage unit 71 stores print data, the number of prints, maximum ribbon speeds Va and Va' described later, a transport amount L1, and the like. The print data and the number of prints are set in the storage unit 71 by being input from the external device 100 or the external terminal 150 to the control unit 7 via the inter-device controller 110 .

A program executed by the control unit 7 may be downloaded from the external terminal 150 via the communication I/F 72, for example. The control unit 7 may store the program acquired from the external terminal 150 in the storage unit 71 via the communication I/F 72 . The print data, medium speed V, and setting information may be input from the operation unit 73 of the printing apparatus 1 and set in the storage unit 71 .

<Outline of printing operation>
3 and 4, the outline of the printing operation for forming a print image on the print medium P in the printing system 8 will be described. 3 and 4, the ink ribbon 9 is shown linearly for easy understanding. However, in practice, the ink ribbon 9 and the print medium P may bend. Also, the operation of the printing apparatus 1 will be mainly described, and the description of the transported print medium P will be simplified. As shown in FIG. 3(a), the thermal head 3 is arranged at a head position 3A in the up-down direction and at a standby position in the left-right direction before executing the printing operation.

In the printing system 8, the printing operation is performed by the printing device 1 while the transportation of the printing medium P and the ink ribbon 9 is stopped. The external device 100 transmits a print command to the printing apparatus 1 via the inter-device controller 110 at a predetermined timing. When the print command is received from the external device 100, the printing apparatus 1 executes a head lowering process as shown in FIG. 3(b). In the head lowering process, the thermal head 3 is driven by the third motor 83 to move vertically from the head position 3A to the head position 3B. The thermal head 3 approaches the platen 20 from above and urges the ink ribbon 9 against the printing surface of the printing medium P. As shown in FIG. The platen 20 contacts the surface of the print medium P opposite to the print surface and urges the ink ribbon 9 and the print medium P toward the thermal head 3 .

After the head lowering process is completed, the print process is executed as shown in FIG. 3(c). In the printing process, the thermal head 3 is driven by the fourth motor 84 to move leftward while urging the ink ribbon 9 from above. At this time, the thermal head 3 is heated by energization based on the print data set in the storage unit 71 . The ink in the used area 91 of the ink ribbon 9 is transferred to the printing surface of the printing medium P. As shown in FIG. A print image is formed on the print medium P by the above.

After the printing process is completed, the head raising process is executed as shown in FIG. 3(d). In the head raising process, the thermal head 3 is driven by the third motor 83 to move vertically from the head position 3B to the head position 3A. The thermal head 3 is separated above the ink ribbon 9 to release the biasing force of the ink ribbon 9 against the platen 20 .

After the head raising process is completed, the carrying process is executed as shown in FIG. 3(e). In the transport process, the first motor 81 and the second motor 82 are driven to rotate the first spool 21 and the second spool 22 . The ink ribbon 9 is let out from the supply roll 9A of the first spool 21 and wound up on the take-up roll 9B of the second spool 22 . The encoder 811 outputs a signal indicating the detected amount of rotation of the guide shaft 65 to the controller 7 . Based on the received signal indicating the amount of rotation of the guide shaft 65, the control unit 7 measures the transport amount and transport speed of the ink ribbon 9 being transported. Further, the thermal head 3 is driven by the fourth motor 84 to move rightward to the standby position. After the transport process is completed, the thermal head 3 is placed at a vertical position that is a head position 3A and a horizontal position that is a standby position, as shown in FIG. 3A.

As shown in FIG. 5, in the transport process, the transport speed of the ink ribbon 9 is accelerated at an acceleration A from zero to the maximum ribbon speed Va. The maximum ribbon speed Va is the target reaching speed of the ink ribbon 9 set by the external device 100 or the external terminal 150 . Thereafter, the conveying speed of the ink ribbon 9 is decelerated from the maximum ribbon speed Va to zero at the acceleration -A. The total transport amount of the ink ribbon 9 from the time the ink ribbon 9 is transported to the time Ta completes the transport is Lta. The total transport amount Lta is equal to the amount of ink ribbon 9 used in the printing process, that is, the amount by which the heated thermal head 3 moves to the left. The constant-velocity transport amount by which the ink ribbon 9 is transported at the constant velocity of the maximum ribbon velocity Va is La. The constant-speed transport amount La is the length of the ink ribbon 9 accelerated to the maximum ribbon speed Va from the amount (Lta) of the ink ribbon 9 used in the printing process, that is, the amount of movement of the heated thermal head 3 to the left, and the length of the ribbon. It is the length obtained by subtracting the total length of deceleration from the maximum speed Va to zero.

In this embodiment, diameter correction processing of the supply roll 9A and the take-up roll 9B, which will be described later, is performed based on the encoder output when the ribbon is fed at a constant speed. The constant-speed transport amount La varies depending on the print data set in the storage unit 71 . When the constant-speed transport amount La is small, the time during which the ribbon is transported at the constant maximum ribbon speed Va is shortened. In this case, the encoder 811 cannot accurately detect the amount of rotation of the guide shaft 65 .

If the constant-speed conveying amount La is shorter than the predetermined conveying amount L1, the controller 7 determines that the encoder 811 cannot detect it accurately. Va'. Let La' be the constant-speed transport amount of the ink ribbon 9 transported at the constant speed of the maximum ribbon speed Va'. As a result, as shown by the dashed-dotted line in FIG. 5, even when the same total transport amount Lta is transported, the time during which the ribbon is transported at the maximum ribbon speed Va′ and the constant-speed transport amount La′ are different from those at the maximum ribbon speed Va. time and the constant-speed transport amount La. Therefore, the encoder 811 can accurately detect the amount of rotation of the guide shaft 65 . Q1 is a pattern in which the ink ribbon 9 is conveyed in the conveying process with the total conveying distance Lta, the maximum ribbon speed Va, the constant conveying distance La, the acceleration A, and the required time Ta. Q2 is a pattern in which the ink ribbon 9 is conveyed with the total conveying distance Lta, the maximum ribbon speed Va', the constant conveying distance La', the acceleration A, and the required time Ta'.

When the ink ribbon 9 is conveyed in the pattern Q2, the required time Ta' may become excessively long. Further, the degree of control over the transport speed (transport amount) of the ink ribbon 9 varies depending on the diameters of the supply roll 9A and the take-up roll 9B. More specifically, the amount of the ink ribbon 9 that the first motor 81 feeds out from the supply roll 9A with one pulse signal increases as the diameter of the supply roll 9A increases. The amount of the ink ribbon 9 wound around the take-up roll 9B by the second motor 82 with one pulse signal increases as the diameter of the take-up roll 9B increases. Therefore, if the diameter of either the supply roll 9A or the take-up roll 9B is large, the controller 7 cannot finely control the transport speed (transport amount) of the ink ribbon 9 .

If the required time Ta' is excessively long in the pattern Q2, or if the constant-speed transport amount La' is shorter than the predetermined transport amount L1, the controller 7 sets the total transport amount of the ink ribbon 9 in the transport process to Ltb. do. The total transport amount Ltb is larger than the usage amount (Lta) of the ink ribbon 9 in the printing process. Q3 is a pattern in which the ink ribbon 9 is conveyed with a total conveying distance Ltb, a maximum ribbon speed Va, a constant-speed conveying distance Lb (Lb≧L1) conveyed at the maximum ribbon speed Va, an acceleration A, and a required time Tb in the conveying process. It says.

After the ink ribbon 9 is conveyed in the pattern Q3 in the conveying process, the pullback process shown in FIG. 4(f) is executed. In the pull-back process, the first motor 81 and the second motor 82 are rotationally driven in the direction opposite to the conveying process, and the ink ribbon 9 usage (Lta) in the printing process is excessively increased in the conveying process of the pattern Q3. The difference (Ltb−Lta) from the transported total transport amount Ltb of the ink ribbon 9 is pulled back from the take-up roll 9B to the supply roll 9A. Note that when the ink ribbon 9 is transported in the patterns Q1 and Q2 in the transport process, the pullback process is not executed.

<Correction of Diameter of Supply Roll 9A and Winding Roll 9B>
As described above, the diameters of the supply roll 9A and the take-up roll 9B are one of the important parameters for the controller 7 to control the transport speed and transport amount of the ink ribbon 9 . The control unit 7 uses the encoder 811 to detect the diameters of the supply roll 9A and the take-up roll 9B at the start of the printing operation. Further, when the conveying process is performed, the control section 7 executes a correction process for correcting the detected diameters of the supply roll 9A and the take-up roll 9B.

In the correction process, the control unit 7 determines the constant-speed transport amount La (Lb) of the ink ribbon 9 set by the control unit 7 before the transport process and the constant-speed transport amount of the ink ribbon 9 measured based on the detection result of the encoder 811. Compare with Lm. If the measured constant-speed transport amount Lm is larger than the set constant-speed transport amount La (Lb), the ink ribbon 9 is excessively transported, and the actual diameters of the supply roll 9A and the take-up roll 9B are the detected values. bigger than Therefore, the detected diameters of the supply roll 9A and the take-up roll 9B are corrected by adding the correction value β. On the other hand, when the measured constant-speed transport amount Lm is smaller than the set constant-speed transport amount La (Lb), the transport of the ink ribbon 9 is insufficient, and the actual diameters of the supply roll 9A and the take-up roll 9B are detected. smaller than the value Therefore, the detected diameters of the supply roll 9A and the take-up roll 9B are corrected by subtracting the correction value β.

In this embodiment, the correction value β is calculated by the following formula (1). Note that Vm is the maximum ribbon speed measured by the control unit 7 based on the detection result of the encoder 811 . When the ink ribbon 9 is conveyed in the pattern Q2, Va is replaced with Va'. F is a predetermined coefficient.
β=|Vm−Va|×F (1)

<Main processing>
The main processing of the printing apparatus 1 will be described with reference to FIGS. 6 and 7. FIG. The main process is a process for the printing apparatus 1 to form a print image on the print medium P. FIG. Before starting the main process, the storage unit 71 stores in advance the print data to be printed, the number of prints, the maximum ribbon speeds Va and Va', and the transport amount L1. The number of prints is the number of repetitions of printing on the print medium P in the main process. The storage unit 71 also stores a withdrawal flag used in the main process. The retraction flag is set to 1 when the ink ribbon 9 is transported in the pattern Q3 in the transport process, and is set to 0 when the ink ribbon 9 is transported in the patterns Q1 and Q2.

Upon receiving the print command, the control unit 7 of the printing apparatus 1 reads out and executes a program stored in the storage unit 71 to start main processing. As shown in FIG. 6, the control unit 7 performs an initial operation (S1). The initial operation is processing for controlling the printer 1 to the initial state. In the initial operation, the controller 7 moves the thermal head 3 to the head position 3A and uses the encoder 811 to detect the diameters of the supply roll 9A and the take-up roll 9B.

The control unit 7 acquires the print data, the number of prints, the maximum ribbon speed Va, and the acceleration A from the storage unit 71 (S2). The control unit 7 calculates the total transport amount Lta and the constant-speed transport amount La based on the acquired print data, ribbon maximum speed Va, and acceleration A (S3).

The control unit 7 determines whether or not the calculated constant-speed transport amount La is equal to or greater than the transport amount L1 stored in the storage unit 71 (S4). If the constant-speed transport amount La is equal to or greater than the transport amount L1 (S4: YES), the encoder 811 detects the amount of rotation of the guide shaft 65 with sufficient accuracy even when the ink ribbon 9 is transported in the pattern Q1. judge that it can be done. Then, the control unit 7 sets the ink ribbon 9 to be transported in the pattern Q1 (total transport amount Lta, constant-speed transport amount La, ribbon maximum speed Va) in the transport process described later (S5), and the process proceeds to S11.

If the constant-speed transport amount La is smaller than the transport amount L1 (S4: NO), the control unit 7 determines the total transport amount Ltb and the constant-speed transport amount Lb in the pattern Q3 based on the print data, the ribbon maximum speed Va, and the acceleration A. , the required time Tb is calculated (S6). Based on the total transport distance Lta, the reduced maximum ribbon speed Va', and the acceleration A, the controller 7 calculates the required time Ta' in the pattern Q3 and the constant-speed transport distance La' at the maximum ribbon speed Va' (S7 ).

The control unit 7 determines whether or not the constant-speed transport amount La' is greater than or equal to the transport amount L1 stored in the storage unit 71 (S8). If the constant-speed transport amount La' is greater than or equal to the transport amount L1 (S8: YES), it is determined whether or not the required time Ta' calculated in S7 is equal to or shorter than the required time Tb calculated in S6 (S9). If the required time Ta' is equal to or shorter than the required time Tb (S9: YES), the controller 7 determines that the amount of rotation of the guide shaft 65 can be detected with sufficient accuracy even when the ink ribbon 9 is conveyed in the pattern Q2. . Then, the control unit 7 sets to transport the ink ribbon 9 in the pattern Q2 (total transport amount Lta, constant-speed transport amount La', ribbon maximum speed Va') in the transport process to be described later (S10). The control unit 7 sets the value of the pullback flag stored in the storage unit 71 to 0 (S11), and shifts the process to S21.

If the constant-speed transport amount La' is smaller than the transport amount L1 (S8: NO) or the required time Ta' is greater than the required time Tb (S9: NO), the controller 7 transports the ink ribbon 9 in pattern Q2. It is determined that the amount of rotation of the guide shaft 65 can be detected with sufficient accuracy when The control unit 7 sets to transport the ink ribbon 9 in the pattern Q3 (total transport amount Ltb, constant-speed transport amount Lb, maximum ribbon speed Va) in the transport process to be described later (S12). The control unit 7 sets the value of the pullback flag stored in the storage unit 71 to 1 (S13), and shifts the process to S21.

As shown in FIG. 7, the controller 7 executes a head lowering process (S21). In the head lowering process, the thermal head 3 is driven by the third motor 83 to move vertically from the head position 3A to the head position 3B. The thermal head 3 approaches the platen 20 from above and urges the ink ribbon 9 against the printing surface of the printing medium P. As shown in FIG.

The control unit 7 starts print processing (S22). In the printing process, the thermal head 3 is driven by the fourth motor 84 to move leftward while urging the ink ribbon 9 from above. The control unit 7 causes the heating elements of the thermal head 3 to generate heat based on the print data, and prints on the print medium P. FIG.

The control unit 7 determines whether printing is completed (S23). If it is determined that the printing is not completed (S23: NO), the control section 7 returns the process to S23 and repeats the determination of S23 until the printing is completed. When it is determined that the printing is completed (S23: YES), the control section 7 stops driving the fourth motor 84 and heating of the heating elements of the thermal head 3, and ends the printing process (S24).

The controller 7 executes a head raising process (S25). In the head raising process, the thermal head 3 is driven by the third motor 83 to move vertically from the head position 3B to the head position 3A. The thermal head 3 is separated above the ink ribbon 9 .

The controller 7 starts the transport process (S31). In the transport process, the control unit 7 drives the first motor 81 and the second motor 82 based on the transport pattern set in S5, S10, and S13 (see FIG. 6). The first spool 21 and the second spool 22 rotate, and the ink ribbon 9 is let out from the supply roll 9A of the first spool 21 and wound onto the take-up roll 9B of the second spool 22. As shown in FIG. The control unit 7 executes measurement processing (S32). In the measurement process, the controller 7 measures the transport amount and the transport speed of the transported ink ribbon 9 based on the detection result of the encoder 811 .

The controller 7 determines whether or not the transport of the ink ribbon 9 has been completed (S33). If it is determined that the required time Ta (Ta', Tb) has not elapsed and the transport of the ink ribbon 9 has not been completed (S33: NO), the control unit 7 returns the process to S33 and the transport is completed. The determination of S33 is repeated until. When it is determined that the required time Ta (Ta', Tb) has elapsed and the transport of the ink ribbon 9 is completed (S33: YES), the controller 7 stops driving the first motor 81 and the second motor 82. The transport process is terminated (S34).

The control unit 7 determines whether or not the retraction flag is 1 (S35). If it is determined that the transport pattern is set to Q1 and Q2 and the pullback flag is 0 (S35: NO), the control unit 7 shifts the process to S41. If it is determined that the transport pattern is set to Q3 and the pullback flag is 1 (S35: YES), the controller 7 executes the pullback process (S36). In the pullback process, the control unit 7 reversely drives the first motor 81 and the second motor 82 to pull back the ink ribbon 9 from the take-up roll 9B to the supply roll 9A. The control unit 7 shifts the process to S41.

The control unit 7 executes correction processing (S41). In the correction process, the controller 7 corrects the diameters of the supply roll 9A and the take-up roll 9B detected in S1 based on the transport amount and transport speed of the ink ribbon 9 measured in the measurement process (S34).

The control unit 7 determines whether or not all printing for the number of prints has been completed (S42). If it is determined that all printing has not been completed (S42: NO), the control section 7 returns the process to S21 and repeats the processes of S21 to S42. If it is determined that all printing for the number of prints has been completed (S42: YES), the control section 7 terminates the main processing.

As described above, the printing system 8 of this embodiment includes the printing device 1 and the control section 7 . The printing apparatus 1 includes a thermal head 3 , a transport mechanism 6 , a supply roll 9A, a take-up roll 9B, and an encoder 811 . The transport mechanism 6 includes a first spool 21 , a second spool 22 , a first motor 81 , a second motor 82 and a guide shaft 65 . The supply roll 9A is attached to the first spool 21 . The winding roll 9B is attached to the second spool 22 . An encoder 811 detects the rotational position and amount of rotation of the guide shaft 65 . The control unit 7 executes a print process in which the thermal head 3 heats the ink ribbon 9 to print on the print medium P (S22). After executing the printing process, the control unit 7 executes the conveying process and drives the first motor 81 and the second motor 82 (S31). The ink ribbon 9 is let out from the supply roll 9A of the first spool 21 and wound up on the take-up roll 9B of the second spool 22 . When the ink ribbon 9 is transported in the pattern Q3, the total transport amount Ltb of the ink ribbon 9 is larger than the amount (Lta) of the ink ribbon 9 used in the printing process. The encoder 811 outputs to the controller 7 a signal indicating the amount of rotation of the guide shaft 65 detected in the transport process. The control unit 7 executes measurement processing, and measures the transport amount and transport speed of the transported ink ribbon 9 based on the detection result of the encoder 811 (S34). The controller 7 executes correction processing to correct the diameters of the supply roll 9A and the take-up roll 9B based on the measured transport amount and transport speed of the ink ribbon 9 (S41). The printing system 8 transports the ink ribbon 9 with a total transport amount Ltb larger than the usage amount (Lta) of the ink ribbon 9 in the printing process. Since the conveying amount of the ink ribbon 9 is increased, the detection accuracy of the encoder 811 is increased. Therefore, the printing system 8 can correctly correct the diameters of the supply roll 9A and the take-up roll 9B.

After the ink ribbon 9 is conveyed in the pattern Q3 in the conveying process, the controller 7 executes the pullback process (S36). In the pull-back process, the first motor 81 and the second motor 82 are driven to rotate in the direction opposite to the conveying process, and the ink ribbon 9 is pulled back from the take-up roll 9B to the supply roll 9A. As a result, the printing system 8 can prevent the transport amount of the ink ribbon 9 from becoming excessive.

The printing system 8 corrects the diameters of the supply roll 9A and the take-up roll 9B through correction processing. The degree of control over the transport speed (transport amount) of the ink ribbon 9 varies depending on the diameters of the supply roll 9A and the take-up roll 9B. Since the printing system 8 can correctly correct the diameters of the supply roll 9A and the take-up roll 9B, the transport speed (transport amount) of the ink ribbon 9 can be controlled correctly.

If the controller 7 determines that the encoder 811 can detect the ink ribbon 9 with sufficient accuracy even if the total transport amount Lta is equal to the amount of ink ribbon 9 used in the printing process, the controller 7 determines that the ink ribbon 9 in the patterns Q1 and Q2 in the transport process. A ribbon 9 is conveyed. In the patterns Q1 and Q2, the ink ribbon 9 is transported by the total transport amount Lta. As a result, the printing system 8 can prevent the transport amount of the ink ribbon 9 from becoming excessive in the transport process.

The control unit 7 determines whether or not the constant-speed transport amount La transported at the ribbon maximum speed Va is greater than or equal to the transport amount L1 stored in the storage unit 71 (S4). If the constant-speed transport amount La is equal to or greater than the transport amount L1 (S4: YES), the controller 7 transports the ink ribbon 9 at the pattern Q1 (the maximum ribbon speed Va) in the transport process. If the constant-speed conveying amount La is smaller than the conveying amount L1 (S4: NO), the control section 7 conveys the ink ribbon 9 in the pattern Q2 (ribbon maximum speed Va'<Va) in the conveying process. When the ink ribbon 9 is transported at the maximum ribbon speed Va′, the ink ribbon 9 slips less on the first spool 21, the second spool 22, and the guide shaft 60 than when transported at the maximum ribbon speed Va. do. Therefore, the detection accuracy of the encoder 811 is improved, and the printing system 8 can correctly correct the diameters of the supply roll 9A and the take-up roll 9B.

The printing apparatus 1 includes a fourth motor 84 that moves the ink ribbon 9 facing the thermal head 3 at least in the left-right direction parallel to the conveying direction. The control unit 7 executes the printing process while the printing medium P and the ink ribbon 9 are stopped from being conveyed. In the printing process, the thermal head 3 is driven by the fourth motor 84 to move leftward while urging the ink ribbon 9 from above. At this time, the ink ribbon 9 is heated by the thermal head 3 . Even when the printing system 8 intermittently conveys the ink ribbon 9, the detection accuracy of the encoder 811 is high. Therefore, the printing system 8 can correctly correct the diameters of the supply roll 9A and the take-up roll 9B.

In the above embodiment, the controller 7 corresponds to the "controller" of the present invention. The first spool 21 corresponds to the "supply portion" of the present invention. The second spool 22 corresponds to the "receiving portion" of the present invention. The guide shaft 65 corresponds to the "roller" of the invention. The encoder 811 corresponds to the "detector" of the present invention. The total transport amount Lta corresponds to the "first distance" of the invention. The total transport amount Ltb corresponds to the "second distance" of the invention. The transporting process for transporting the ink ribbon 9 in the pattern Q3 corresponds to the "first transporting process" of the present invention. The diameter of the supply roll 9A and the take-up roll 9B corresponds to the "amount related to the ink ribbon" of the present invention. The conveying process for conveying in patterns Q1 and Q2 corresponds to the "second conveying process" of the present invention. The ribbon maximum speed Va corresponds to the "first speed" of the present invention. The maximum ribbon speed Va' corresponds to the "second speed" of the present invention. The horizontal direction corresponds to the "first direction" of the present invention. The fourth motor 84 corresponds to the "head motor" of the present invention.

The present invention can be variously modified from the above embodiment. The various modified examples described below can be combined as long as there is no contradiction. In the above embodiment, the control unit 7 of the printing apparatus 1 executes the main processing (see FIGS. 6 and 7), but the control unit 111 of the inter-device controller 110 executes part or all of the main processing. good too. For example, the control unit 111 may execute processing (S3 to S13) related to setting of the transport processing in the main processing.

In the above embodiment, the diameters of the supply roll 9A and the take-up roll 9B are corrected by correction processing, but the present invention is not limited to this. For example, a process of correcting the pulse signals of the first motor 81 and the second motor 82 may be performed in the correction process. Specifically, the detection result of the encoder 811 or the deviation of the conveying amount is calculated, and the number of pulses included in the pulse signal sent to the first motor 81 or the second motor 82 is increased or decreased according to the deviation. Also good. Also, the masses of the supply roll 9A and the take-up roll 9B may be corrected. In this case, the mass of the supply roll 9A and the take-up roll 9B corresponds to the "amount related to the ink ribbon" of the present invention.

The guide shaft 60 may have an encoder for detecting the amount and position of rotation of a guide shaft other than the guide shaft 65 . The control unit 7 may measure the conveying speed and the conveying amount based on the detection result of the encoder provided on the first spool 21 or the second spool 22 in addition to the encoder 811 . For example, when the first motor 81 and the second motor 82 are brushless motors, the encoder 811 and the encoder provided on the first spool 21 or the second spool 22 are used together to measure the transport speed and the transport amount. .

In the above-described embodiment, after the ink ribbon 9 is conveyed in the pattern Q3, the pull-back process (S36) is performed, and then the correction process (S41) is performed. may be performed. In this case, in the pullback process, the conveying amount, the conveying speed, etc. may be controlled based on the diameters of the supply roll 9A and the take-up roll 9B corrected by the correction process. Further, even when the ink ribbon 9 is conveyed in the pattern Q3, the withdrawal process (S36) does not necessarily have to be executed. For example, if it is desired to process the next printing operation quickly, the printing operation may be started without performing the pullback process. Although the consumption of the ink ribbon increases as the number of printing operations increases, the printing process can be performed quickly while performing appropriate correction processing.

In the above embodiment, the printing apparatus 1 intermittently conveys the ink ribbon 9 and executes the printing process while the conveyance of the print medium P and the ink ribbon 9 is stopped, but the present invention is not limited to this. For example, the present invention can be applied to a case where printing is performed while the ink ribbon 9 is continuously transported and the transport amount of the ink ribbon 9 is changed relative to the transport amount of the print medium P. In this case, the printer 1 does not have to include the fourth motor 84 .

1 Printing Device 2 Ribbon Mounting Unit 3 Thermal Head 7 Control Unit 8 Printing System 21 First Spool 22 Second Spool 65 Guide Shaft 71 Storage Unit 81 First Motor 82 Second Motor 84 Fourth Motor 811 Encoder

Claims (8)

Equipped with a printing device and a control unit,
The printing device
a thermal head;
A mechanism for conveying an ink ribbon, comprising: a supply unit capable of supplying the ink ribbon to the thermal head; and a receiving unit provided on the opposite side of the thermal head to the supply unit and capable of receiving the ink ribbon. and a roller rotatable following the ink ribbon transported between the supply section and the reception section;
A detection unit that detects the amount of rotation of the roller,
The control unit
a print process in which the thermal head heats the ink ribbon to print on a print medium;
A process in which the transport mechanism transports the ink ribbon from the supply unit to the reception unit, and includes a first transport process in which the ink ribbon is transported a second distance longer than the first distance used in the printing process. a transportation process;
a measurement process for measuring at least one of a transport speed and a transport length of the ink ribbon transported in the transport process based on the detection result of the detection unit;
and a correction process for correcting set values relating to transport of the ink ribbon by the transport mechanism based on the measurement result of the measurement process. 2. The printing system according to claim 1, wherein the control section performs a pull-back process in which the transport mechanism pulls back the ink ribbon to the supply section after the first transport process. 3. A printing system according to claim 1, wherein said correction processing corrects, as said set value, an amount of said ink ribbon in at least one of said supply section and said receiving section. The printing device includes a stepping motor that drives the transport device,
4. The printing system according to any one of claims 1 to 3, wherein the correction process corrects a driving signal of the stepping motor as the set value. The control unit
In the conveying process, the conveying mechanism can execute a second conveying process of conveying the ink ribbon of the first distance from the supply unit to the receiving unit,
5. The printing system according to any one of claims 1 to 4, wherein one of the first conveying process and the second conveying process is switched to be executed according to the first distance. The control unit
conveying the ink ribbon at one of a predetermined first speed and a second speed slower than the first speed in accordance with the first distance when executing the second conveying process; 6. The printing system of claim 5. The printing device comprises a head motor for moving the thermal head at least in a first direction parallel to the transport direction of the ink ribbon facing the thermal head,
The control unit
In the printing process, printing is performed by heating the thermal head while moving the thermal head in the first direction by means of the head motor while the transport of the ink ribbon in the transport process is temporarily stopped. The printing system according to any one of claims 1 to 6, characterized by: a thermal head, a mechanism for conveying an ink ribbon, and a supply section capable of supplying the ink ribbon to the thermal head, and a supply section provided on the opposite side of the thermal head to the supply section to receive the ink ribbon. a receiving portion, a roller rotatable following the ink ribbon transported between the supplying portion and the receiving portion; and a detecting portion for detecting the amount of rotation of the roller. A printing method using a printing device comprising:
a printing step in which the thermal head heats the ink ribbon to print on a print medium;
The conveying mechanism conveys the ink ribbon from the supply unit to the receiving unit, and includes a first conveying step of conveying the ink ribbon a second distance longer than the first distance used in the printing step. a conveying process;
a measuring step of measuring at least one of a conveying speed and a conveying length of the ink ribbon conveyed in the conveying step based on the detection result of the detecting unit;
and a correction step of correcting set values relating to transport of the ink ribbon by the transport mechanism based on the measurement result of the measurement step.

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