JP2013071442A - Printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printer which surely prevents the step-out state of a pulse motor, thereby smoothly drives components.SOLUTION: The printer includes a motor driving circuit 73 which outputs a plurality of pulse instructions, a sheet feeding motor 72 which rotates following a plurality of pulse instructions, a platen roller 26 for transferring a length-unfixed roll sheet 3A, etc., a thermal head 31 which performs desired printing based on print data, and a thermal head driving circuit 71 which carries out current-supply control of switching a current-supply pattern for each line print data in correspondence to a print cycle T. The printer changes output patterns of a plurality of pulse instructions to control the rotation speed of the sheet feeding motor 72, and determines whether a step-out state has occurred, in which the rotation of the sheet feeding motor 72 falls into disorder in following the plurality of pulse instructions. When the step-out state has occurred, the printer increases or decreases the value of a first target speed V1 to set a corrected target speed that prevents the step-out state, thereby sets the corrected target speed as a second target speed V2.

Description

  The present invention relates to a printing apparatus that performs desired printing on a print medium.

  As a technique related to a printing apparatus that conveys a printing medium using a driving force of a pulse motor and performs desired printing, there is a technique described in Patent Document 1, for example. In this conventional printing apparatus, a printing medium (recording paper) is conveyed by the conveying means, and a desired print is formed on the conveyed printing medium by a thermal head. At this time, the transport unit transports the print medium using the driving force of the pulse motor (transport motor). The pulse motor rotates by a predetermined angle (step rotation) by giving one pulse command (switching the excitation phase to the next state). Therefore, the rotation speed of the pulse motor is determined by a plurality of pulse commands. The target speed is set so as to correspond to

  At this time, the pulse motor repeats rotation at a predetermined angle every time the pulse command is input, and therefore vibration is generated when the motor rotates. In particular, if the natural frequency of a rotating system such as a rotor or gear matches the interval (driving frequency) of the pulse command, a resonance phenomenon occurs and the vibration becomes large. There may be a step-out phenomenon in which followability to a plurality of pulse commands is disturbed. For example, this resonance frequency usually exists in the vicinity of a relatively low frequency band of about 100 to 200 Hz. Therefore, when performing a printing operation, it is desirable to avoid a frequency band in which a resonance frequency exists, in which such a step-out phenomenon may occur.

  In the above prior art, from the above viewpoint, the target speed is determined so as to avoid a frequency band in which a frequency band in which the resonance frequency is expected to occur is fixed in advance. The

JP-A-2005-59521

  However, the prior art has the following problems. That is, the natural frequency causing the resonance phenomenon on the pulse motor side is a value unique to each individual motor, even for a plurality of motors of the same specification (form), for example. Different values. Therefore, when the target speed is set so as to avoid the determined frequency range in common with a plurality of pulse motors as in the above prior art, each motor is individually handled with great care. Can not do it. In other words, there is a waste of performing target correction for a pulse motor that does not need to be corrected and the target speed is not necessary, or conversely, target correction is performed for a pulse motor that requires correction of the target speed. There is a risk of missing corrections that are not made. As a result, it has been difficult to reliably perform smooth pulse motor driving without step-out.

  An object of the present invention is to provide a printing apparatus that can surely prevent a pulse motor from stepping out and perform smooth driving.

  To achieve the above object, the present invention provides a pulse output means for outputting a plurality of pulse commands, a pulse motor for rotationally driving following the plurality of pulse commands from the pulse output means, A transport means for transporting the print medium using a driving force, and a plurality of heating elements that respectively form dots on each print line obtained by dividing the print medium into print resolution in the transport direction, Output of the plurality of pulse commands from the pulse output means in accordance with a thermal head for forming a desired print based on print data on the print medium and a first target speed set corresponding to the print data In accordance with a printing cycle that is an interval between energization timing corresponding to the first target speed, and a conveyance control means that changes the mode and controls the rotation speed of the pulse motor. A printing control unit that performs energization control for switching an energization mode for each line print data obtained by dividing the print data into one print line unit, wherein the rotation speed of the pulse motor is controlled by the conveyance control unit. A step-out determination means for determining whether or not a step-out phenomenon occurs in which followability to the plurality of pulse commands in the rotation of the pulse motor is disturbed after the control is performed to achieve the first target speed. When the step-out determining means determines that the step-out phenomenon has occurred, the value of the first target speed is increased or decreased so that the step-out phenomenon does not occur, and a new second target speed is obtained. And a target speed correcting means, wherein the transport control means controls the rotational speed of the pulse motor to be the second target speed.

  In the present invention, the printing medium is conveyed by the conveying means, and desired printing based on the printing data is formed on the conveyed printing medium by the thermal head. This thermal head includes a plurality of heating elements. The plurality of heating elements perform print formation by forming dots on each print line of the print medium. Specifically, under the control of the printing control means, the energization mode of the heating element is changed corresponding to the fact that the printing medium is conveyed by the conveying means and the print line of the printing medium sequentially passes through the position of the heating element. The line print data is sequentially switched. As a result, the thermal head can perform print formation at a printing speed that matches the conveyance speed of the print medium by the conveyance means.

  At this time, in this invention, a conveyance means conveys a to-be-printed medium using the drive force of a pulse motor. The rotational speed of the pulse motor is controlled by a plurality of pulse commands from the pulse output means. The pulse motor rotates by a predetermined angle (step rotation) by giving one pulse command (switching the excitation phase to the next state). In the present invention, the pulse output means shortens or lengthens the interval between the plurality of pulse commands based on the control of the conveyance control means, thereby controlling the rotation speed by following the plurality of pulse commands. Do. The rotational speed can be accelerated by gradually shortening the interval, and the rotational speed can be decelerated by gradually increasing the interval. The conveyance control unit controls the pulse output unit according to the target speed (first target speed) set corresponding to the print data so that the rotation speed of the pulse motor becomes the first target speed. To do.

  And in this invention, a step-out determination means and a target speed correction means are provided. The step-out determination means determines whether or not a step-out phenomenon has occurred after the rotation speed of the pulse motor reaches the first target speed under the control of the conveyance control means. If a step-out phenomenon has occurred, the target speed correcting means increases or decreases the value of the first target speed to obtain a second target speed at which the step-out phenomenon does not occur. The conveyance control unit controls the rotation speed of the pulse motor so as to become the new second target speed.

  In this way, by adjusting the target speed value to increase or decrease when the step-out phenomenon occurs, even if the step-out phenomenon occurs due to the occurrence of the resonance phenomenon described above, the rotational speed of the pulse motor is changed to By shifting the frequency, the resonance phenomenon is prevented from occurring, and the step-out phenomenon can be eliminated. Thereby, smooth pulse motor drive without step-out can be performed, and the printing quality can be improved.

  In addition, the natural frequency that causes the resonance phenomenon on the pulse motor side is a value that is unique to each motor and is slightly different for each motor. In the present invention, after detecting that the step-out phenomenon due to the resonance phenomenon has actually occurred, the value of the target speed at that time is corrected to avoid resonance. Therefore, it is possible to deal with each motor individually and finely as compared with a method of setting a target speed so as to avoid a frequency region that is appropriately determined in advance for a plurality of pulse motors in advance. As a result, there is a waste of correcting the target speed for a pulse motor that does not need to be corrected and the target speed is not required. There is no possibility of correction omission without speed correction, and smooth pulse motor driving without step-out can be performed reliably.

  According to the present invention, the step-out of the pulse motor can be reliably prevented and smooth driving can be performed.

It is a perspective view showing the tape printer by one embodiment of the present invention in the state where the upper cover was removed. It is the perspective view showing the state which removed the upper cover of the tape printer, and the expansion perspective view of W section. It is a sectional side view of the tape printer of the state which removed the upper cover. It is the perspective view from the front upper side showing a roll sheet holder, and the perspective view from lower back. It is a circuit block diagram which shows the circuit structure of a tape printer. It is an acceleration table used for speed control of a sheet feeding motor. It is a reduction table used for speed control of a sheet feed motor. It is explanatory drawing showing the example of the acceleration / deceleration behavior of a sheet feeding motor. It is explanatory drawing which shows an example of the threshold voltage of the output voltage of a sensor. It is explanatory drawing which shows an example of the potential difference of the output voltage of a sensor. It is explanatory drawing for demonstrating generation | occurrence | production of the conveyance abnormality by a step-out phenomenon. It is a flowchart showing the control procedure performed by CPU.

  Embodiments of the present invention will be described below with reference to the drawings. This embodiment is an embodiment when the present invention is applied to a tape printing apparatus as a printing apparatus.

<Configuration of tape printer>
First, the configuration of the tape printer according to the present embodiment will be described with reference to FIGS. As shown in FIGS. 1 to 3, the tape printer 1 includes a main body housing 2 and a roll sheet holder 3 around which an indefinite length roll sheet 3 </ b> A or a die-cut label sheet (not shown) as a non-printing medium is wound. Is accommodated in the roll sheet holder accommodating portion 4, and the upper portion is covered with an upper cover made of a transparent resin (not shown) attached to the rear upper edge so as to be freely opened and closed. Further, a tray 6 made of transparent resin standing so as to face the front center of the upper cover (not shown), a power button 7 disposed on the front side of the tray 6, and a left and right movable to the front side surface portion. And a cutter lever 9 that moves the cutter unit 8 (see FIG. 3) to the left and right. Further, a power cord 10 (see FIG. 3) is connected to one side end of the back surface of the main body housing 2, and a USB (Universal) connected to a personal computer or the like (not shown) is connected to the other side end. A connector portion (not shown) composed of a serial bus or the like is provided.

  The indefinite length roll sheet 3A is a long heat-sensitive sheet having a self-coloring property (so-called thermal paper) or a long shape in which a release paper is bonded to one side of the heat-sensitive sheet via an adhesive. And is wound around the core such that the back side is the outside. In addition, on the back side of the indefinite length roll sheet 3A, a predetermined pitch p (for example, 10 [mm], 20 [mm], 30 [ mm] etc.), a plurality of encoder marks 5 (detected marks) are formed. In this example, the dimension of each encoder mark 5 in the conveyance direction is formed at half the predetermined pitch p, that is, p / 2. At this time, since the back surface side of the indefinite length roll sheet 3A is white, it becomes a light reflection region, and the encoder mark 5 is a black light absorption region.

  Although the detailed illustration of the die-cut label sheet is omitted, a plurality of labels formed of a heat-sensitive sheet (so-called thermal paper) having a self-coloring property on the surface side of a long release paper has an adhesive. Are temporarily attached so as to be arranged along the longitudinal direction of the release paper, and are wound around the core so that the back surface side of the release paper is on the outside. Further, on the back side of the die-cut label sheet, an encoder mark 5 similar to the above is formed at a position facing a photo sensor 11 as a mark detection sensor, which will be described later, so as to face the edge portion on the conveyance direction side of each label. Has been.

  Further, the tape printing apparatus 1 configures the roll sheet holder 3 at one side edge portion (right side edge portion in FIG. 2) in a direction substantially perpendicular to the conveyance direction of the roll sheet holder storage portion 4. A holder support member 15 is provided in which a mounting member 13 having a substantially rectangular cross-section protruding from the positioning holding member 12 can be fitted. The holder support member 15 is formed with a first positioning groove portion 16 that is open in an upward direction and is substantially U-shaped in front view. Further, an engagement recess 15A is formed at the inner base end of the holder support member 15 to be engaged with an elastic locking piece 12A (see FIG. 4 to be described later) protruding from the lower end of the positioning holding member 12. Has been.

  Moreover, it extends substantially horizontally from the rear end edge of the insertion port 18 for inserting the indefinite length roll sheet 3A or the die-cut label sheet to the front upper end edge of the roll sheet holder storage part 4 to be described later. There is provided a mounting portion 21 on which the tip portion of the guide member 20 that constitutes the same is mounted. In addition, at the edge corner on the rear side in the transport direction of the mounting portion 21, there are four second L-shaped cross sections corresponding to a plurality of width dimensions of the indefinite length roll sheet 3 </ b> A or the die-cut label sheet. Positioning groove portions 22A to 22D are formed. As shown in FIG. 3, each of the second positioning groove portions 22 </ b> A to 22 </ b> D is configured so that a part of the portion that contacts the placement portion 21 of the guide member 20 constituting the roll sheet holder 3 can be fitted from above. Is formed. Further, the distal end portion of the guide member 20 constituting the roll sheet holder 3 extends to the insertion port 18.

  In addition, the bottom surface portion of the roll sheet holder storage portion 4 has a positioning recess 4A having a horizontally long rectangular shape in a plan view substantially perpendicular to the transport direction from the inner base end portion of the holder support member 15 to a position facing the second positioning groove portion 22A. Is formed at a predetermined depth (for example, a depth of about 1.5 to 3 [mm]). The width direction of the positioning recess 4 </ b> A is formed so as to be substantially equal to the width dimension of the lower end edge portions of the positioning holding member 12 and the guide member 20 constituting the roll sheet holder 3. Further, the inner base end portion of the holder support member 15 of the positioning recess 4A faces a later-described sheet discriminating portion 60 (see FIG. 4 described later) that extends from the lower end edge of the positioning holding member 12 in a substantially perpendicular inner direction. Discrimination of a vertically long rectangular plan view in the conveying direction formed so that a portion to be deepened by a predetermined depth (for example, a depth of about 1.5 to 3 [mm]) further than the positioning recess 4A A recess 4B is formed.

  The discriminating recess 4B is composed of a push-type microswitch or the like, the type of the indefinite length roll sheet 3A or die-cut label sheet, the material of the heat sensitive sheet, the roll sheet width, the feed pitch p of the encoder mark, etc. Five sheet discrimination sensors S1, S2, S3, S4, and S5 for discriminating are provided in an L shape. Each of the sheet discrimination sensors S1 to S5 is a known mechanical switch including a plunger and a micro switch, and the upper end of each plunger is located near the bottom of the positioning recess 4A from the bottom of the discrimination recess 4B. It is provided to protrude. Then, it is detected whether or not there are sensor holes 60A to 60E (see FIG. 4 to be described later) of the sheet determining unit 60 for the sheet determining sensors S1 to S5. The type of the indefinite length roll sheet 3A or die-cut label sheet mounted on the roll sheet holder 3, the material of the heat sensitive sheet, the roll sheet width, the feed direction pitch p of the encoder mark, and the like are detected.

  In this example, in each tape discrimination sensor S1 to S5, the plunger always protrudes from the bottom surface of the discrimination recess 4B to the vicinity of the bottom surface of the positioning recess 4A, and the microswitch is in the OFF state. And when each sensor hole 60A-60E of the sheet | seat discrimination | determination part 60 exists in the position which opposes each sheet | seat discrimination | determination sensor S1-S5, since a plunger is not pressed down and a micro switch is in an OFF state, an OFF signal is sent. Is output. On the other hand, when each of the sensor holes 60A to 60E of the sheet determination unit 60 is not located at a position facing each of the sheet determination sensors S1 to S5, the plunger is pressed and the micro switch is turned on, so that an ON signal is generated. Is output. Accordingly, when each sheet determination sensor S1 to S5 outputs a 5-bit “0” or “1” signal and all the sheet determination sensors S1 to S5 are in the off state, that is, the roll sheet holder 3 is not mounted. In this case, a 5-bit “00000” signal is output.

  Further, the side edge (on the right edge in FIG. 2) of the insertion port 18 on the holder support member 15 side is formed at a position facing the inner end surface of the positioning member 12 fitted into the holder support member 15. . Further, a guide rib portion is erected on the side edge portion of the insertion port 18 on the holder support member 15 side.

  In addition, the vertical movement operation of the thermal head 31 (see FIG. 3) or the like is performed on the front end portion in the transport direction of the other side edge portion (left side edge portion in FIG. 2) of the roll sheet holder storage portion 4. A lever 27 for performing is provided. That is, by rotating the lever 27 upward, the thermal head 31 is moved downward to move away from the platen roller 26 (conveying means, see FIG. 3), and by rotating the lever 27 downward, The thermal head 31 is moved upward, and the indefinite length roll sheet 3A or the die-cut label sheet is pressed against the platen roller 26 so that printing is possible.

  The thermal head 31 has a plurality of heating elements arranged in an orthogonal direction perpendicular to the tape conveyance direction, each forming a dot on each print line obtained by dividing the indefinite length roll sheet 3A into a print resolution in the tape conveyance direction. (Not shown). The thermal head 31 performs printing according to the print data on the indefinite length roll sheet 3 </ b> A sandwiched between the thermal head 31 and the platen roller 26 by energizing the heating element according to the print data.

  In addition, a control circuit board 32 (see FIG. 5 to be described later) formed with a control circuit unit 61 (see FIG. 5 to be described later) is formed below the roll sheet holder storage unit 4 in accordance with a command from an external personal computer or the like. 3).

  The roll sheet holder 3 mounted with the roll sheet 3A wound around the core or the die-cut label sheet is fitted with the mounting member 13 of the positioning member 12 in the first positioning groove portion 16 of the holder support member 15, and the positioning member 12 The elastic locking piece 12A protruding from the lower end is engaged with the engagement recess 15A formed at the inner base end of the holder support member 15, and the lower surface of the distal end of the guide member 20 is set to each second positioning groove 22A. The lower end portion of the guide member 20 is fitted into and brought into contact with the positioning recess 4A by being fitted into ˜22D, and is detachably attached to the roll sheet holder storage portion 4. Further, a sheet determination unit 60 provided at the inner lower edge of the positioning member 12 is inserted into the determination recess 4B, and the sheet determination unit 60 facing each of the sheet determination sensors S1 to S5 disposed in the determination recess 4B. It is possible to detect whether each of the sensor holes 60A to 60E is present. That is, it becomes possible to detect the type of the indefinite length roll sheet 3A or the die-cut label sheet mounted on the roll sheet holder 3.

  Then, the indefinite length roll sheet 3 </ b> A or the indefinite length roll sheet 3 </ b> A or the die cut label sheet is brought into contact with the inner side surface of the guide member 20 by rotating the lever 27 upward. Inserting the other side edge portion of the die-cut label sheet into the insertion port 18 while abutting the guide rib portion standing on the side edge portion of the insertion port 18 and rotating the lever 27 downward. Thus, printing becomes possible.

  Here, as shown in FIG. 3, by rotating the lever 27 downward, the roll sheet 3 </ b> A inserted from the insertion opening 18 is pressed toward the platen roller 26 by the line-type thermal head 31. Be energized by. While the platen roller 26 is rotationally driven by a sheet feed motor 72 (see FIG. 5 described later), the thermal head 31 is driven and controlled to convey the indefinite length roll sheet 3A or the die-cut label sheet. Image data can be printed sequentially on the printing surface of the thermal sheet. Further, the indefinite length roll sheet 3A or the die-cut label sheet discharged onto the tray 6 is cut by the cutter unit 8 by moving the cut lever 9 in the right direction.

  Reflective light as an optical sensor is positioned near the edge on the holder support member 15 side of the lower end surface portion on which the back side of the indefinite length roll sheet 3A or die-cut label sheet conveyed as described above slides. A photo sensor 11 as a sensor is arranged. Thereby, the encoder mark 5 formed on the back surface of the indefinite length roll sheet 3A or the die-cut label sheet is detected by the photosensor 11. In addition, the photo sensor 11 should just be provided in the position facing the back surface side of the minimum width dimension of 3A of indefinite length roll sheets or a die-cut label sheet. Thereby, it can respond to all kinds of each width dimension of this indefinite length roll sheet 3A or a die-cut label sheet.

<Roll sheet holder>
Next, a schematic configuration of the roll sheet holder 3 will be described with reference to FIG. The roll sheet holder 3 is mounted with the indefinite length roll sheet 3A or the die-cut label sheet so as to be rotatable in the circumferential direction. However, because of the same configuration, the state in which the indefinite length roll sheet 3A is mounted is taken as an example. explain.

  As shown in FIG. 4, the roll sheet holder 3 to which the indefinite length roll sheet 3 </ b> A wound around the core is mounted includes a guide member 20, and a first cylinder is provided on the inner surface of the guide member 20. A portion (not shown) is erected. Correspondingly, a second cylinder (not shown) is erected on the inner surface of the positioning holding member 12. The first cylinder portion (not shown) is fitted into one end edge of the cylindrical hole of the core of the indefinite length roll sheet 3A, and thereby the indefinite length roll sheet 3A is inserted into the inner surface of the guide member 20. One end face is in contact. Further, the second cylindrical portion (not shown) is fitted into the other end side edge portion of the cylindrical hole of the winding core of the indefinite length roll sheet 3 </ b> A, whereby the indefinite length is formed on the inner surface of the positioning holding member 12. The other end face of the roll sheet 3A is in contact with the roll sheet 3A. A substantially cylindrical holder shaft member 40 is provided between the guide member 20 and the positioning and holding member 12. One end side end of the holder shaft member 40 is attached to a flange portion 36 formed on the outer peripheral portion of the one end side end surface of the guide member 20, and the other end side end of the holder shaft member 40 is the first end of the positioning holding member 12. Two cylinders are fitted and inserted. Thereby, by changing the length dimension of the holder shaft member 40, it is possible to easily produce a plurality of types of roll sheet holders 3 to which the indefinite length roll sheet 3A or the die-cut label sheet having different width dimensions is attached. .

  The guide member 20 extends downward from the lower outer peripheral portion of the outer end surface of the first tube portion and is fitted into a positioning recess 4 </ b> A formed on the bottom surface portion of the roll sheet holder storage portion 4. A first extending portion 42 that is in contact with the bottom surface of the positioning recess 4A is formed. In addition, the guide member 20 is formed with a second extending portion 43 that extends outward so as to cover an outer end surface portion on a substantially 1/4 circumference in the front direction of the indefinite length roll sheet 3A. Further, a third extending portion 44 is formed in which the upper edge extends from the outer peripheral portion of the second extending portion 43 to the vicinity of the insertion port 18 (see FIG. 3) of the indefinite length roll sheet 3A. Has been. The lower end surface of the distal end portion of the third extending portion 44 is formed substantially horizontally and abuts on the mounting portion 21 of the tape printer 1 so that the third extending portion 44 and the second extending portion 43 are in contact with each other. It is configured to guide one end edge portion of the indefinite length roll sheet 3 </ b> A attached by the inner side surface to the insertion port 18.

  Further, a fourth extending portion 45 is formed that extends a predetermined length from the position facing the rear end edge in the transport direction of the mounting portion 21 on the lower end surface of the third extending portion 44 to the first extending portion 42. When the lower end surface of the third extending portion 44 comes into contact with the placement portion 21, the leading end portion in the transport direction of the fourth extending portion 45 is attached to the fixed length roll sheet 3A. It is comprised so that it may fit in either of each 2nd positioning groove part 22A-22D which opposes the sheet | seat width (refer FIG. 3).

  At this time, the winding in which the indefinite length roll sheet 3 </ b> A is wound by the first tube portion erected on the inner surface of the guide member 20 and the second tube portion erected on the inner surface of the positioning holding member 12. The core is held rotatably. The holder shaft member 40 is provided with a plurality of types of length dimensions corresponding to each length dimension of the core of the indefinite length roll sheet 3A or the die-cut label sheet.

  In addition, the longitudinally long cross section of the outer end surface portion of the positioning member 12 is substantially vertically long so as to be substantially perpendicular to the axial center from the end edge portion of the axial center of the holder shaft member 40. A rectangular attachment member 13 is projected. The attachment member 13 is formed so as to be narrow in the downward direction when viewed from the front, and is in the first positioning groove 16 (see FIG. 1 and the like) that is narrow in the downward direction of the holder support member 15 of the tape printer 1. It is formed so that it can adhere. Further, the protruding height dimension of the mounting member 13 is formed substantially equal to the width dimension of the first positioning groove 16.

  Further, the lower end portion of the attachment member 13 of the positioning member 12 has a predetermined length in the lateral direction from the lower end portion of the attachment member 13 (in this example, about 1.5 [mm] to 3 [mm]. ] In the shape of a flat plate having a substantially rectangular shape in front view (in this example, a thickness of about 1.5 [mm] to 3 [mm]) is formed. Thus, when the roll sheet holder 3 is mounted, the mounting member 13 is placed in the first positioning groove portion 16 while the guide portion 57 formed at the lower end portion of the mounting member 13 is brought into contact with the outer end surface of the holder support member 15. By inserting, the roll sheet holder 3 can be mounted while being positioned easily.

  Further, the lower end edge portion of the extending portion 56 of the positioning member 12 is lower than the lower end edge portion of the guide member 20 by a predetermined length (in this example, approximately 1 [mm] to 2.5 [mm]). A substantially rectangular sheet discriminating portion 60 that is extended so as to protrude in the direction and that extends a predetermined length in a substantially right-angled inner direction is formed at the lower edge.

  Further, as shown in FIG. 4B, in the sheet discriminating unit 60, as described above, the sensor holes 60A to 60E are substantially L-shaped at predetermined positions facing the sheet discriminating sensors S1 to S5. Arranged and drilled. As a result, since each sensor hole 60A-60E is perforated at a maximum of five, the presence / absence of each sensor hole 60A to 60E corresponds to “1” and “0”, so that the indefinite number attached to the roll sheet holder 3 is determined. The type of the long roll sheet 3A and the die-cut label sheet, the material of the heat sensitive sheet, the roll sheet width, the conveyance direction pitch p of the encoder mark 5, etc. can be displayed by a 5-bit code.

  In addition, a vertically long rectangular through hole 62 is formed in the extending portion 56 at the lower end portion of the mounting member 13 of the positioning member 12, and the upper end edge of the through hole 62 is directed downwardly toward the distal end and outwardly toward the distal end portion. An elastic locking piece 12 </ b> A in which a protruding portion is formed is provided.

<Circuit configuration of tape printer>
Next, the circuit configuration of the tape printer 1 configured as described above will be described with reference to FIG. As shown in FIG. 5, the control circuit unit 61 formed on the control board 32 of the tape printer 1 includes a CPU 62, a CG (character generator) ROM 63, a ROM 64, a flash memory (EEPROM) 65, a RAM 66, an input / output interface ( I / F) 67, a communication interface (I / F) 68, and the like. The CPU 62, the CGROM 63, the ROM 64, the flash memory 65, the RAM 66, the input / output interface (I / F) 67, and the communication interface (I / F) 68 are connected to each other by a bus line 69 so that data can be transmitted between them. Exchanges take place.

  Here, the dot pattern data corresponding to each character is stored in the CGROM 63, and the dot pattern data is read from the CGROM 63, and the indefinite length roll sheet 3A or the heat-sensitive sheet of the die-cut label sheet based on the dot pattern data. A dot pattern is printed on top.

  The ROM 64 stores various programs, and stores various programs necessary for control of the tape printer 1 such as an indefinite length roll sheet 3A or a die cut label sheet conveyance processing program described later. The ROM 64 stores a plurality of types of conveyance direction width dimensions of the encoder mark 5 and the potential difference of the output voltage of the photosensor 11 depending on whether the indefinite length roll sheet 3A or the die-cut label sheet is used. A mark length output voltage table storage area 64 </ b> A for storing the mark length output voltage table 75 is provided. Further, the types of the indefinite length roll sheet 3A and the die-cut label sheet, the material of the heat sensitive sheet, the roll sheet width, the feed pitch p of the encoder mark 5 and the like for each 5-bit code input from each of the sheet discrimination sensors S1 to S5 Is provided with a roll sheet type storage area 64B.

  For example, in the roll sheet type storage area 64B, the 5-bit code input from each of the sheet discrimination sensors S1 to S5 is “11100”, the type: “indefinite length roll sheet 3A”, the material of the thermal sheet: “Material A”, roll sheet width: “100 [mm]”, transport direction pitch p of encoder mark 5: “5 [mm]”, and the like are stored. For the 5-bit code “11000”, the type: “indefinite length roll sheet 3A”, the material of the heat sensitive sheet: “material B”, the roll sheet width: “100 [mm]”, the encoder mark 5 In the conveyance direction pitch p: “5 [mm]” and the like are stored. Further, when the 5-bit code is “10110”, the type: “die cut label sheet”, the material of the heat sensitive sheet: “material A”, the roll sheet width: “100 [mm]”, the transport direction of the encoder mark 5 Pitch p: “5 [mm]” or the like is stored. Also, for the 5-bit code “10100”, the type: “die cut label sheet”, the material of the heat sensitive sheet: “material B”, the roll sheet width: “100 [mm]”, the transport direction of the encoder mark 5 Pitch p: “5 [mm]” or the like is stored.

  When the material of the thermal sheet is “Material A”, the maximum conveyance speed of the thermal sheet that can be printed via the thermal head 31 is 80 [mm / sec], and the material of the thermal sheet is “Material”. “80 [mm / sec]” is stored in advance in the ROM 64 as the conveyance speed of the indefinite length roll sheet 3A of “A”. When the material of the thermal sheet is “material B”, the maximum conveyance speed of the thermal sheet that can be printed via the thermal head 31 is 20 [mm / sec], and the material of the thermal sheet is “material”. “20 [mm / sec]” is stored in advance in the ROM 64 as the conveyance speed of the indefinite length roll sheet 3A of “B”.

  The CPU 62 performs various calculations based on the various programs stored in the ROM 64. In addition, the ROM 64 classifies outline data (outline data) that defines the outline of each character for each type of character (such as Gothic typeface, Mincho typeface) for each character such as a large number of characters. Stored in correspondence with the code data. Based on the outline data, dot pattern data is developed on the print buffer 66A.

  Further, the flash memory 65 stores dot pattern data such as external character data received from an external computer device or the like, dot pattern data of various symbol data, and the like with a registration number. The flash memory 65 retains the stored contents even when the tape printer 1 is turned off.

  The RAM 66 temporarily stores various calculation results calculated by the CPU 62. The RAM 66 is provided with various memories such as a print buffer 66A and a work area 66B. The print buffer 66A stores a dot pattern for printing such as a plurality of characters and symbols, the number of applied pulses that is the amount of energy for forming each dot, and the like as dot pattern data. Dot printing is performed according to the dot pattern data stored in.

  The input / output I / F 67 rotationally drives the sheet discrimination sensors S1 to S5, the photo sensor 11, the thermal head drive circuit 71 (printing control means) for driving the thermal head 31, and the platen roller 26. A motor drive circuit 73 (pulse output means) that outputs a plurality of pulse commands for driving the sheet feed motor 72 is connected to each other.

  The thermal head control circuit 71 performs energization control corresponding to the print data on the heating elements of the thermal head 31. Specifically, the thermal head control circuit 71 starts the conveyance of the indefinite length roll sheet 3A or the die-cut label sheet by the platen roller 26, and then the energization timing interval corresponding to the target speed (described later) of the sheet feed motor 72 ( The energization mode is switched for each line print data obtained by dividing the print data into one print line unit corresponding to the print cycle.

  The sheet feed motor 72 is constituted by a pulse motor and is driven to rotate following the plurality of pulse commands of the motor drive circuit 73. In the present embodiment, the sheet feeding motor 72 will be described below as an example in which the sheet feeding motor 72 is associated as one line and one pulse. In other words, by applying one pulse to the sheet feeding motor 72, the platen roller 26 is driven to rotate so that the indefinite length roll sheet 3A or the die-cut label sheet corresponds to one print line divided into print resolutions in the transport direction. Only to be transported. However, the present invention is not limited to this, and other correspondences such as 1 line-2 pulse may be used.

  In addition, the communication I / F 68 is configured by, for example, a USB (Universal Serial Bus) or the like, and is connected to an external computer device by a USB cable or the like to enable bidirectional data communication.

<Features of this embodiment>
In the above configuration, the present embodiment is characterized in that it is determined whether or not a step-out phenomenon has occurred in the sheet feed motor 72 in accordance with the detection result of the encoder mark 5. It is to increase or decrease the rotation speed. Hereinafter, the details will be described in order.

<General characteristics of pulse motor>
As described above, the sheet feed motor 72, which is a pulse motor, is a drive source for the platen roller 26 that conveys the indefinite length roll sheet 3A or the die-cut label sheet (hereinafter, referred to as “indefinite length roll sheet 3A etc.” as appropriate). The rotation speed is controlled by the motor drive circuit 73. The sheet feed motor 72 rotates by a predetermined angle by applying one pulse (switching the excitation phase to the next state), and rotates by shortening or lengthening the interval (pulse period) for applying the pulse. Speed control is performed. The rotational speed of the sheet feed motor 72 can be accelerated by gradually shortening the interval, and the rotational speed of the sheet feed motor 72 can be decelerated by gradually increasing the interval.

  In the present embodiment, in order to realize such acceleration behavior (or deceleration behavior) of the sheet feeding motor 72, the mode (or the maximum) when the pulse application interval is reduced to the minimum value and the minimum value in advance. A value and a mode when the value is increased to its maximum value) are patterned, and are prepared as a plurality of types of acceleration tables and deceleration tables in the ROM 64 (see FIGS. 6 and 7 described later). Thus, when the motor drive circuit 73 actually controls the rotational speed of the sheet feeding motor 72, one of the plurality of types of tables is selected, and the sheet feeding motor is selected along the selected acceleration / deceleration table. By issuing a pulse to 72, a desired acceleration behavior (or deceleration behavior) can be easily realized.

<Basic motor table>
Here, since the motor is configured to rotate a rotor having a large inertia, it is difficult to suddenly accelerate or decelerate. Also, the pulse-speed correlation that allows efficient drive control from the stop state to the maximum speed state is uniquely determined from the characteristics of each motor. Therefore, in general, the pulse number range corresponding to the stop state of the pulse motor to the maximum speed state (in this embodiment, 8 pulses as shown in FIGS. 6A and 7A described later). In the acceleration / deceleration table prepared in plural types, the acceleration / deceleration behavior from the acceleration / deceleration start point to the acceleration / deceleration completion point in the acceleration / deceleration pulse number is determined.

  In the present embodiment, the pulse-speed correlation that defines the reference acceleration / deceleration characteristics between the stop state and the maximum speed state of the sheet feeding motor 72 is determined by actual measurement as a basic motor table (not shown). ing. In the acceleration table / deceleration table prepared in plural types, acceleration from the acceleration / deceleration start point to the acceleration completion point with the above 8 pulses (corresponding to 8 lines on the assumption of the above-mentioned 1 line-1 pulse) as one unit. The behavior and the deceleration behavior are determined from the deceleration start point to the deceleration completion point. In this case, at the time of speed control, the target speed of the sheet feed motor 72 to be realized after the pulse number range (8 pulses) from the present is set, and the deviation between the current speed and the target speed after the 8 pulses is set. Accordingly, the acceleration table or the deceleration table is selected, and the motor speed is controlled. In this embodiment, as will be described later, the target speed is discretely set in four stages of “highest speed”, “high speed”, “medium speed”, and “low speed”.

<Acceleration table>
Examples of the acceleration table are shown in FIGS. In each table, the rotation speed of the sheet feeding motor 72 is expressed in terms of “cycle [ms]” that is an interval of pulses applied to the sheet feeding motor 72 in order to realize the rotation speed. “Line” represents a print line obtained by dividing the above-described indefinite length roll sheet 3A or the like into print resolution in the transport direction.

  FIG. 6A shows a first acceleration table used when accelerating from a stopped state to the highest speed (in this example, a period of 1.6 [ms]). In this example, the sheet feeding motor 72 has a period of 50 [ms] in the first line (first pulse) one line after the stop state, and a period of 40 [ms] in the next second line (second pulse). Thereafter, the speed is gradually increased, and the final eighth line (eighth pulse) has a characteristic of reaching a period of 1.6 [ms] corresponding to the highest speed (FIG. 8A described later). See also).

  FIG. 6B shows a second acceleration table used when accelerating from the stop state to the second highest speed (hereinafter simply referred to as “high speed”, in this example, a period of 2 [ms]). As above, the first line has a period of 50 [ms], the second line has a period of 40 [ms], and then gradually accelerates, and the seventh line has a period of 2 [ms] corresponding to the high speed. After that, the speed is constant, and the cycle of the same speed is 2 [ms] in the final eighth line (see also FIG. 8A described later).

  FIG. 6C shows a third acceleration table used when accelerating from the stop state to the second slowest speed (hereinafter simply referred to as “medium speed”. In this example, the cycle is 4 [ms]). As in the above, the cycle is 50 [ms] on the first line and 40 [ms] on the second line, and then gradually accelerates, and the cycle 4 [ms] corresponding to the medium speed is obtained on the sixth line. After that, the speed becomes constant, and the same speed period 4 [ms] is obtained in the next seventh line and the final eighth line (see also FIG. 8A described later).

  FIG. 6D shows a fourth acceleration table used when accelerating from the slowest speed (hereinafter simply referred to as “low speed”, in this example, the cycle 6 [ms]) to the highest speed. That is, the sheet feeding motor 72 has a cycle 4 [ms] corresponding to the medium speed on the first line one line after the low speed state, a cycle 2 [ms] corresponding to the high speed on the second line, and the third line. After a period of 1.6 [ms] corresponding to the maximum speed is reached, the speed is constant, and the final speed of the last line is 1.6 [ms] (FIG. 8B described later). See also).

  FIG. 6E shows a fifth acceleration table used when accelerating from the low speed to the high speed. The first line has a period of 4 [ms] corresponding to the medium speed, and the second line has the above. After reaching 2 [ms] corresponding to the high speed, the speed becomes constant, and the cycle of the same speed is 2 [ms] in the final eighth line (see also FIG. 8B described later).

  FIG. 6 (f) shows a sixth acceleration table used when accelerating from the medium speed to the maximum speed. The first line has a period 2 [ms] corresponding to the high speed, and the second line. After reaching 1.6 [ms] corresponding to the maximum speed, the speed is constant, and the cycle of the same speed is 1.6 [ms] in the final eighth line (see FIG. 8C described later). reference).

  The 3 ′ acceleration table and the 3 ′ acceleration table shown in FIG. 6G will be described later.

<Deceleration table>
Examples of the deceleration table are shown in FIGS. “Cycle [ms]” and “line” are the same as described above.

  FIG. 7A shows a first deceleration table used when decelerating from the maximum speed to the stop state. In this example, the sheet feeding motor 72 changes from the cycle 2 [ms] corresponding to the highest speed to the cycle 2 [ms] corresponding to the high speed in the first line (first pulse) after one line, and the next In the second line (second pulse), the cycle corresponds to the medium speed is 4 [ms]. Thereafter, the speed is gradually decreased, and the cycle is 50 [ms in the last previous seventh line (seventh pulse). ] And then stop at the final eighth line (see also FIG. 8A described later).

  FIG. 7B shows a second deceleration table used when decelerating from the high speed to the stop state. Similarly to the above, the same speed from the state of the cycle 2 [ms] corresponding to the high speed to the first line is shown. The cycle is 2 [ms], after which deceleration is started, the cycle is 4 [ms] on the second line, the cycle is 6 [ms] on the third line, and after that, the cycle is gradually decelerated, and the cycle is 50 on the seventh line. It has a characteristic of stopping at the final eighth line after reaching [ms] (see also FIG. 8A described later).

  FIG. 7C shows a third deceleration table used when decelerating from the medium speed to the stop state. Similarly to the above, the third deceleration table is the same from the state of the cycle 4 [ms] corresponding to the medium speed to the second line. The cycle of speed is 4 [ms]. After that, deceleration is started, the cycle is 6 [ms] on the third line, the cycle is 10 [ms] on the fourth line, and then gradually decelerates. It has a characteristic of stopping at the final eighth line after the period 50 [ms] (see also FIG. 8A described later).

  FIG. 7D shows a fourth deceleration table used when decelerating from the maximum speed to the low speed. Similarly to the above, from the state of the cycle 1.6 [ms] corresponding to the maximum speed to the fifth line. The cycle is 1.6 [ms] at the same speed. After that, deceleration starts, the cycle is 2 [ms] on the 6th line, the cycle is 4 [ms] on the 7th line, and the low speed is handled on the final 8th line. The cycle is 6 [ms] (see also FIG. 8B described later).

  FIG. 7E shows a fifth deceleration table used when decelerating from the high speed to the low speed. Similarly to the above, the period of the same speed from the state of the cycle 2 [ms] corresponding to the high speed to the sixth line. After that, deceleration is started, and the cycle is 4 [ms] on the 7th line and 6 [ms] corresponding to the low speed on the final 8th line (FIG. 8B described later). See also).

  FIG. 7 (f) shows a sixth deceleration table used when decelerating from the maximum speed to the medium speed. Similarly to the above, the sixth line from the state of the cycle 1.6 [ms] corresponding to the maximum speed is shown. The cycle of the same speed is 1.6 [ms] until thereafter, and deceleration is started, and the cycle is 2 [ms] on the seventh line and the cycle 4 [ms] corresponding to the medium speed on the final eighth line. (See also FIG. 8B described later).

  The 3 ′ deceleration table and the 3 ′ deceleration table shown in FIG. 7G will be described later.

<Example of acceleration / deceleration characteristics>
In the present embodiment, one specific acceleration table selected from the acceleration tables shown in FIGS. 6A to 6G and the deceleration table shown in FIGS. 7A to 7G are selected. The motor drive circuit 73 controls the rotation speed of the sheet feeding motor 72 to be the above-described target speed by using one specific deceleration table. Examples of acceleration / deceleration control of the sheet feeding motor 72 realized by such control are shown in FIGS. In the characteristic line represented by the solid line in FIG. 8A, the first 8 pulses accelerate from the stop state to the highest speed (using the first acceleration table), and the subsequent 12 pulses are the highest speed constant speed rotation. In this case, the last 8 pulses are decelerated from the highest speed to the stop state (using the first deceleration table). In the characteristic line represented by the one-dot chain line in FIG. 8A, the first 7 pulses accelerate from the stop state to the high speed (using the second acceleration table), and the subsequent 10 pulses become the high speed constant speed rotation. After that, the case where the speed is decelerated from the high speed to the stop state in the last 7 pulses (using the second deceleration table) is shown. In the characteristic line represented by the broken line in FIG. 8A, the first 6 pulses accelerate from the stop state to the medium speed (using the third acceleration table), and the subsequent 12 pulses are the constant speed rotation of the medium speed. In this case, the vehicle is decelerated from the medium speed to the stop state in the last 6 pulses (using the third deceleration table).

  Further, in the characteristic line represented by the solid line in FIG. 8B, the first three pulses are accelerated from the low speed to the maximum speed (using the fourth acceleration table), and the subsequent 18 pulses are the maximum constant speed. The figure shows a case where the speed is reduced from the maximum speed to the low speed in the last three pulses (using the fourth deceleration table) after the rotation. In the characteristic line represented by the one-dot chain line in FIG. 8B, the first two pulses are accelerated from the low speed to the high speed (using the fifth acceleration table), and the subsequent 20 pulses are the high-speed constant speed rotation. Then, the case where the speed is reduced from the high speed to the low speed in the last two pulses (using the fifth deceleration table) is shown.

  In the characteristic line shown by the solid line in FIG. 8C, the first two pulses accelerate from the medium speed to the highest speed (using the sixth acceleration table), and the subsequent 20 pulses are the highest speed constant speed rotation. After that, the case where the vehicle is decelerated from the maximum speed to the medium speed state in the last two pulses (using the sixth deceleration table) is shown.

  The characteristic line shown in FIG. 8D will be described later.

<Setting target speed>
Here, the setting of the target speed of the sheet feeding motor 72 already described is performed in accordance with the energization control content in the thermal head 31. For example, first, a single energization time Th to the heat generating area of the thermal head 31 is determined based on operating environment information such as the voltage of the tape printer 1 detected by a known method and the ambient temperature of the printer 1. The As an example, when the ambient temperature of the tape printer 1 is low, it takes time to develop a color of a heat sensitive sheet such as the indefinite length roll sheet 3A, so that the energization time Th is set longer. Alternatively, when the voltage of the tape printer 1 is high, color development of the heat-sensitive sheet such as the indefinite length roll sheet 3A is completed in a short time by applying a high voltage, so that the energization time Th is set short. The Then, based on the energization time Th determined as described above, the printing cycle T, which is the energization timing interval for the heat generating elements, is determined, and the target speed is determined according to the determined printing cycle T. The At this time, as described above, in the present embodiment, the target speed of the sheet feeding motor 72 is discretely determined in stages such as “highest speed”, “high speed”, “medium speed”, “low speed”, etc. The rotational speed of the sheet feeding motor 72 is controlled using the table or the deceleration table so as to achieve the target speed.

<Step-out phenomenon>
Here, the sheet feed motor 72, which is a pulse motor, repeats the rotation of the predetermined angle every time a pulse command is input as described above, and thus vibration is generated when the motor rotates. In particular, if the natural frequency of a rotating system such as a rotor or gear matches the interval (driving frequency) of the pulse command, a resonance phenomenon occurs and the vibration increases, and when the vibration becomes significant, the rotation of the sheet feed motor 72 is increased. There may be a step-out phenomenon in which the followability to the plurality of pulse commands is disturbed. Therefore, in the present embodiment, the occurrence of the step-out phenomenon is detected based on the detection result of the encoder mark 5 by the photosensor 11. The details will be described below.

<Outline of conveyance status determination based on encoder mark detection>
In the present embodiment, as described above, the detection result of the encoder mark 5 by the photosensor 11 is used to determine whether or not there is an abnormality in the conveyance state of the indefinite length roll sheet 3A, and the abnormality has occurred. In this case, it is specified that the step-out phenomenon has occurred. Here, in the determination of the transport state, in this example, two determination methods (threshold values) are used depending on which of the indefinite length roll sheet 3A and the die-cut label sheet is used as the printing medium. The method using a voltage and the method using a voltage difference are used properly. The details will be described below with reference to FIGS.

<Identification of print medium>
That is, first, the CPU 62 reads a 5-bit code input from each of the sheet determination sensors S1 to S5. At this time, as described above, in the roll sheet type storage area 64B, the types of the indefinite length roll sheet 3A and die cut label sheet corresponding to the 5-bit code, the material of the thermal sheet, the roll sheet width, the encoder mark 5 The data such as the transport direction pitch p is stored. The CPU 62 reads the data such as the type, the material of the heat sensitive sheet, the roll sheet width, the conveyance direction pitch p of the encoder mark 5 and the like. It is determined which of the seats is attached.

<Encoder mark detection for indefinite length roll sheet>
When the indefinite length roll sheet 3A is mounted on the roll sheet holder 3, input from the photo sensor 11 based on potential difference data (for example, 1.50 [V]) predetermined for the indefinite length roll sheet. When the output signal voltage is changed from the predetermined high level voltage to the predetermined low level voltage side by the potential difference of the potential difference data, it is determined that the encoder mark 5 faces the photo sensor 11. That is, when the platen roller 26 rotates and the indefinite length roll sheet 3A is conveyed as described later, the CPU 62 sets the voltage of the output signal waveform 82 of the photosensor 11 to a predetermined high level as shown in FIG. The voltage changed from the level voltage 3 [V] to the low level voltage side of the potential difference of the potential difference data 1.50 [V] and became a voltage of 3 [V] -1.50 [V] = 1.50 [V]. Sometimes, it is determined that the encoder mark 5 faces the photo sensor 11.

<Encoder mark detection for die-cut label sheets>
On the other hand, when a die-cut label sheet is mounted on the roll sheet holder 3, a predetermined output signal of the photosensor 11 is determined based on potential difference data (for example, 2.50 [V]) predetermined for the die-cut label sheet. The voltage on the low level side of the potential difference that is half the potential difference data from the high level voltage is stored in the RAM 66 as a threshold voltage. In this example, the predetermined high level voltage is 3 [V], and the predetermined low level voltage is 0 [V]. Therefore, as shown in FIG. 9, the CPU 62 determines a potential difference 1.25 [V] which is half of the potential difference data 2.50 [V] from the predetermined high level voltage 3 [V] of the output signal waveform 81 of the photosensor 11. Only the low level side voltage 1.75 [V] is stored in the RAM 66 as the threshold voltage. When the platen roller 26 rotates and the die-cut label sheet is conveyed as described later, the CPU 62 sets the voltage of the output signal input from the photosensor 11 to the threshold voltage 1.75 [V]. Then, it is determined that the encoder mark 5 faces the photo sensor 11.

<Step-out occurrence determination based on conveyance status identification>
In any of the encoder mark 5 detection methods described above, in this embodiment, one encoder mark faces the photosensor 11 on the premise that the encoder mark 5 is transported at a transport speed corresponding to the target speed. Thus, it is determined whether or not the next encoder mark 5 has been opposed after a lapse of a predetermined time that matches the transport speed. Thereby, normality / abnormality of the transport state of the indefinite length roll sheet 3A and the like can be identified, and when the transport state is abnormal, it can be considered that the above-mentioned step-out phenomenon has occurred.

  That is, as shown in FIG. 11A, when the step-out phenomenon does not occur in the sheet feed motor 72, the indefinite length roll sheet 3A is fixed in synchronization with the number of pulse commands of the motor drive circuit 73. It is conveyed at a speed Vt. As a result, in the photosensor 11, the time t required from the passage of one encoder mark 5 to the passage of the next encoder mark 5 is time t = p / Vt. For example, when the speed Vt is 80 [mm / sec] and the pitch p of the encoder mark 5 is 10 [mm], the time t is 1/8 [sec].

  On the other hand, when a step-out phenomenon occurs in the sheet feed motor 72 shown in FIG. 11B, the sheet feed motor 72 cannot be synchronized with the number of pulse commands of the motor drive circuit 73, and the indefinite length roll sheet 3A is The sheet is transported at a speed Vt ′ smaller than the speed Vt. As a result, the photosensor 11 cannot detect the next encoder mark 5 even if the time t = p / Vt elapses after one encoder mark 5 passes. That is, the time required from the passage of one encoder mark 5 to the passage of the next encoder mark 5 is longer than the time t (corresponding to the target required time) t ′ (corresponding to the actual required time). It becomes. Therefore, the CPU 62 can determine whether or not a step-out phenomenon has occurred based on the detection timing of the encoder mark 5 as described above in the photosensor 11 (see step S70 in FIG. 12 described later).

<Speed change when step out occurs>
As described above, the step-out phenomenon occurs due to a resonance phenomenon in which the interval (drive frequency) of the pulse command of the sheet feeding motor 72 matches the natural frequency of the rotating system such as the rotor and the gear. Therefore, in the present embodiment, when the step-out phenomenon occurs as described above, the pulse command interval is slightly widened (that is, the motor rotation speed is slowed), or the pulse command interval is slightly narrowed ( That is, increase the motor rotation speed). Therefore, in this embodiment, in order to slightly change the motor rotation speed as described above, the target speed value (speed value that the acceleration table finally reaches after acceleration) is switched to an acceleration table in advance.

  Usually, it is known that the above-described resonance frequency exists in the vicinity of a relatively low frequency band of about 100 to 200 Hz. Therefore, in the present embodiment, the target speed represented by a cycle of 4 [ms] with respect to the third acceleration table (see FIG. 6C) in which the target speed finally reached after acceleration is in the vicinity of the frequency band. 3 ′ acceleration table (refer to FIG. 6 (g)) which is corrected approximately 20% later and set to a cycle of 4.8 [ms], and the target speed is corrected approximately 20% faster to a cycle of 3.2 [ms]. A third “acceleration table is prepared. As shown in FIG. 7G, a third deceleration ′ table and a third ″ corresponding to the third ′ acceleration table and the third ″ acceleration table, respectively. If a step-out phenomenon is detected as described above, instead of the third acceleration table (or third deceleration table) that has been used, the third 3 'or third' table is also provided. Acceleration table (or 3 'or 3' deceleration) Buru) using a rotation speed control of the sheet feed motor 72 is performed.

  Such acceleration / deceleration table switching may be performed immediately (in the middle of acceleration / deceleration control) at the time when the step-out phenomenon occurs, or after the acceleration / deceleration is completed, When the three acceleration table (or the third deceleration table) is selected again for the motor rotation control, the table switching may be performed.

<Control procedure>
A control procedure executed by the CPU 62 to realize the above contents will be described with reference to FIG.

  The flow of FIG. 12 is started when the power button 7 of the tape printer 1 is pressed, for example. In FIG. 12, first, in step S10, the CPU 62 performs a predetermined initialization process such as initialization of various memories. Thereafter, the process proceeds to step S20.

  In step S20, the CPU 62 determines one energization time Th of the thermal head 31 based on the above-described operating environment information and the like, and determines the printing cycle T based on the determined energization time Th. Thereafter, the process proceeds to step S30.

  In step S30, the CPU 62 sets a target speed (first target speed) corresponding to the printing cycle T determined in step S20. Thereafter, the process proceeds to step S40.

  In step S40, the CPU 62 determines whether the acceleration / deceleration start point coincides with the current speed from the acceleration table / deceleration table shown in FIGS. 6 (a) to 6 (f) and FIGS. 7 (a) to (f). An acceleration table or a deceleration table whose completion point is the target speed set as described above is selected, and the pulse period is set accordingly. Thereafter, the process proceeds to step S50.

  In step S50, the CPU 62 outputs a control signal to the motor drive circuit 73, and the indefinite length roll sheet 3A or the like is generated by the plurality of pulse commands of the pulse period along the acceleration table or the deceleration table selected in step S40. In addition to starting conveyance, a control signal is output to the thermal head control circuit 71 to supply power to the thermal head 31 in a cycle based on the pulse cycle, and printing corresponding to the print data is performed on the indefinite length roll sheet 3A or the like. Let it begin. In addition, this step S50 functions as the conveyance control means described in each claim. Thereafter, the process proceeds to step S60.

  In step S <b> 60, the CPU 62 determines whether or not the sheet feeding motor 72 has stepped out based on the detection result of the photosensor 11 by the method described above. If no step-out has occurred, the determination in step S60 is not satisfied (S60: NO), and the process proceeds to step S80 described later. If step-out has occurred, the determination at step S60 is satisfied (S60: YES), and the routine goes to step S70. The step S60 functions as a conveyance state detection unit described in each claim and also functions as a step-out determination unit.

  In step S70, the target speed of the acceleration table or the deceleration table (the third acceleration table or the third deceleration table in the above example) that has been used so far is corrected in response to the occurrence of the step out. (= Second target speed) and the corresponding acceleration table or deceleration table (in the above example, the 3 ′ or 3 ″ acceleration table, or the 3 ′ or 3 ′ deceleration table).

  Note that the switching from the third acceleration table or the third deceleration table to the above may be switched to the 3 ′ acceleration table or the 3 ′ deceleration table if, for example, printing quality is important. When the 3 ′ acceleration table is used, the target speed is corrected to be 20% slower as described above. However, other values may be used as long as they are within 20%. That is, it is sufficient that the second target speed V2 is set such that 0.8V1 ≦ V2 <V1 with respect to the first target speed V1. On the other hand, for example, if emphasis is placed on reliably eliminating step-out, switching to the third "acceleration table or the third" deceleration table may be performed. When the third "acceleration table is used, the target speed is corrected to be 20% faster as described above. However, any other value may be used as long as it is within 20%. On the other hand, it is sufficient that the second target speed V2 is set so that V1 <V2 ≦ 1.2V1 Note that step S70 functions as the target speed correcting means described in each claim. The process moves to S80.

  In step S80, the CPU 62 determines whether or not printing of all lines corresponding to the print data (dot pattern data) developed in the print buffer 66A for the indefinite length roll sheet 3A or the like has been completed. . If printing of all the lines corresponding to the print data is completed, the determination is satisfied (step S80: YES), and this flow ends. If printing of all the lines corresponding to the print data has not been completed, the determination is not satisfied (step S80: NO), the process returns to step S50, and the same procedure is repeated.

  As described above, in the tape printer 1 according to the present embodiment, it is determined whether or not the step-out phenomenon has occurred in the sheet feeding motor 72 in step S60. If a step-out phenomenon has occurred, the target speed value is increased or decreased by switching the acceleration table or the deceleration table in step S70, and as a result, the target speed is set such that the step-out phenomenon does not occur. Thus, by adjusting the target speed value to increase or decrease when the step-out phenomenon occurs, the rotational speed of the sheet feed motor 72 is changed even if the step-out phenomenon occurs due to the occurrence of the resonance phenomenon described above. By shifting the frequency during vibration, the resonance phenomenon is prevented from occurring, and the step-out phenomenon can be eliminated. As a result, the smooth sheet feed motor 72 can be driven without step-out, and the print quality can be improved.

  Further, as already described, the natural frequency that causes the resonance phenomenon on the pulse motor side is a value that is unique to each motor and slightly different for each motor. In the present embodiment, after detecting that the step-out phenomenon due to the resonance phenomenon has actually occurred in the sheet feeding motor 72, the value of the target speed at that time is corrected to avoid resonance. Therefore, it is possible to deal with the sheet feeding motor 72 individually and finely as compared with the method of setting the target speed so as to avoid the frequency region determined appropriately in advance for the plurality of pulse motors in advance. As a result, there is a waste of making corrections to the sheet feed motor 72 that normally does not step out and does not require correction of the target speed, or conversely to the sheet feed motor 72 that requires correction of the target speed. Thus, there is no possibility of a correction omission that is not corrected, and the smooth driving of the sheet feeding motor 72 without step-out can be reliably performed.

  In the present embodiment, in particular, as described above with reference to FIGS. 11A and 11B, a predetermined section (in the above example, from one encoder mark 5 to the next encoder mark 5) is conveyed. The actual required time t ′ required is calculated in step S60 according to the detection result of the photosensor 11, and the occurrence of the step-out phenomenon is determined by comparing this with the target required time t. Accordingly, it is possible to determine the presence or absence of the step-out phenomenon without separately providing an encoder mechanism or the like that directly detects the rotation of the rotor of the sheet feeding motor 72. In addition, it is determined whether or not there is a general step-out phenomenon, not only from various state quantities on the sheet feed motor 72 side as a pulse motor but also from the result of conveyance of the indefinite length roll sheet 3A as a printing medium. Can be performed with high accuracy.

  In this embodiment, in particular, the actual required time required for transporting the predetermined section is calculated based on the timing information at which the photo sensor 11 detects the encoder mark 5. Thereby, it is possible to accurately detect the transport state with a relatively inexpensive and simple structure.

  As described above, instead of detecting the actual time required for transporting a predetermined section of the transported indefinite length roll sheet 3A or the like, the actual transport speed of the indefinite length roll sheet 3A or the like or a predetermined time The actual transport amount in the time range may be detected. In these cases, the first target speed to be realized by the plurality of pulse commands and the actual transport speed, or the target transport amount and the actual transport amount in the predetermined time range are compared. Based on the above, it may be determined whether or not the step-out phenomenon occurs. In this case, the same effect is obtained.

  In the present embodiment, in particular, when the target speed is corrected by switching the third acceleration table to the 3 ′ acceleration table, the first target speed V1 is set to the second target speed V2 that satisfies 0.8V1 ≦ V2 <V1. To correct. This has the following significance. That is, as described above, the step-out phenomenon is caused by the coincidence between the structural natural frequency on the sheet feed motor 72 side and the frequency generated when the motor rotates. Accordingly, when changing the target speed and changing the frequency of rotation, it is sufficient to eliminate the coincidence of the frequencies, and the target speed may be increased or decreased. However, for example, when the duty of the print data is large, the printing capability corresponds to an increase in the conveyance speed of the indefinite length roll sheet 3A, etc., if the target speed is increased due to restrictions on energization control by the thermal head drive circuit 71. There is a possibility that the print quality may be deteriorated due to failure to print. Therefore, in the 3 ′ acceleration table, the second target speed V2 is used in which the first target speed V1 is delayed when the step-out phenomenon occurs. Thereby, the step-out phenomenon can be solved while reliably avoiding the deterioration of the print quality.

  In the present embodiment, in particular, when the target speed is corrected by switching the third acceleration table to the third “acceleration table,” the first target speed V1 is set to the second target speed V2 that satisfies V1 <V2 ≦ 1.2V1. This has the following significance: That is, when the speed is increased from the first target speed V1 to the second target speed V2, the second speed is set within about 20%. It is possible to keep the difference between the target speed V2 and the first target speed V1 to the minimum necessary, and to prevent a sudden change in conveyance and printing state.

  In addition, in the above, the arrow shown in FIG. 5 shows an example of a signal flow, and does not limit the signal flow direction.

  Further, the flowchart shown in FIG. 12 does not limit the present invention to the procedure shown in the above flow, and the procedure may be added or deleted or the order may be changed without departing from the spirit and technical idea of the invention. Good.

  In addition to those already described above, the methods according to the above-described embodiments and modifications may be used in appropriate combination.

  In addition, although not illustrated one by one, the present invention is implemented with various modifications within a range not departing from the gist thereof.

3A indefinite length roll sheet (medium to be printed)
26 Platen roller (conveying means)
31 Thermal head 71 Thermal head drive circuit (printing control means)
72 Sheet feed motor (pulse motor)
73 Motor drive circuit (pulse output means)
V1 1st target speed V2 2nd target speed

Claims (5)

Pulse output means for outputting a plurality of pulse commands;
A pulse motor that rotationally drives following the plurality of pulse commands from the pulse output means;
Transport means for transporting the print medium using the driving force of the pulse motor;
A thermal head comprising a plurality of heating elements for forming dots on each print line obtained by dividing the print medium in the transport direction into print resolutions, and forming a desired print on the print medium based on print data When,
According to a first target speed set corresponding to the print data, a conveyance control unit that changes an output mode of the plurality of pulse commands from the pulse output unit and controls a rotation speed of the pulse motor;
Print control means for performing energization control for switching the energization mode for each line print data obtained by dividing the print data into one print line unit corresponding to a print cycle which is an energization timing interval corresponding to the first target speed. When,
A printing device comprising:
Has the step-out phenomenon occurred in which the followability to the plurality of pulse commands in the rotation of the pulse motor is disturbed after the transfer control means has controlled the rotation speed of the pulse motor to be the first target speed? Step-out determination means for determining whether or not,
When the step-out determining means determines that the step-out phenomenon has occurred, the value of the first target speed is increased or decreased so that the step-out phenomenon does not occur, and a new second target speed is obtained. , Target speed correction means,
Have
The transport control means includes
A printing apparatus that controls the rotation speed of the pulse motor to be the second target speed. The printing apparatus according to claim 1.
Conveyance state detection means for detecting an actual conveyance speed of the printing medium conveyed by the conveyance means, an actual conveyance amount in a predetermined time range, or an actual required time required for conveyance in a predetermined section. ,
The step-out determination means includes
A comparison between the first target speed and the actual transport speed to be realized by the plurality of pulse commands output from the pulse output means according to the first target speed under the control of the transport control means; or The out-of-step phenomenon occurs based on a comparison between the target transport amount in the predetermined time range and the actual transport amount, or a comparison between the target required time required for transport in the predetermined section and the actual required time. A printing apparatus, wherein it is determined whether or not the printer is in a state. The printing apparatus according to claim 2, wherein
The transport state detecting means includes
An optical sensor for optically detecting detected marks previously provided at equal intervals along the transport direction on the print medium;
Based on the timing information at which the optical sensor detects the detected mark, the actual transport speed, the actual transport amount in the predetermined time range, or the actual required time required for transport in the predetermined section, A printing apparatus characterized by calculating The printing apparatus according to any one of claims 1 to 3,
The target speed correcting means is
When it is determined by the step-out determination means that the step-out phenomenon has occurred, the first target speed V1 is set to V1 <V2 ≦ 1.2V1.
The printing apparatus is corrected to the second target speed V2. The printing apparatus according to any one of claims 1 to 3,
The target speed correcting means is
When the step-out determination means determines that the step-out phenomenon has occurred, the first target speed V1 is set to 0.8V1 ≦ V2 <V1.
The printing apparatus is corrected to the second target speed V2.

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