JP2008055604A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a detection error of a movement amount of a paper sheet due to fluttering or bending of the paper sheet and to make an error of a printing position to be within an allowable range. <P>SOLUTION: A second sensor 8 is provided to a position which is away from a thermal head 5 at a prescribed distance B along a conveyance path of a paper sheet 4, and a first sensor 7 is provided to a position which is away from the thermal head 5 at prescribed a distance A longer than the distance B. Either one of detection signals of the first sensor 7 and the second sensor 8 is selected to measure the conveyance amount of the paper sheet according to a magnitude of a conveyance speed and a size of a paper pitch of the paper sheet 4 which are varied in response to a rotational speed of a stepping motor 9 so that a detection error of the movement amount of the paper sheet due to fluttering or bending of the paper sheet is suppressed and shifting of the printing position beyond the allowable range is suppressed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a printing apparatus, and more particularly, to a printing apparatus having two sensors for detecting a paper transport position.

Conventionally, a sensor that detects the amount of paper feed is moved in the width direction of the paper according to the type of paper. However, in order to move the sensor in the width direction of the paper, it is necessary to secure a space allowing the movement in the printer body. For this reason, there has been a problem that the printer tends to be an obstacle to downsizing. In addition, a drive mechanism for moving the sensor is required, which causes a problem that the configuration of the printer is complicated.
Therefore, by disposing the two sensors at predetermined intervals in the width direction of the paper and selecting and using only one of the sensors according to the type of paper, various papers can be used without moving the sensors. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 3-128265

  However, in the background art, the two sensors are arranged at substantially the same position with respect to the paper transport direction. Accordingly, there has been a problem that it is not possible to suppress the detection error of the movement amount or the paper position due to flapping or bending of the paper using these two sensors.

  The present invention has been made in view of such a situation, and by disposing two sensors shifted by a predetermined interval along the sheet conveyance path, and selecting and using one of the sensors as appropriate. Thus, it is possible to suppress the detection error of the sheet movement amount and the sheet position due to the fluttering or bending of the sheet, and to suppress the deviation of the printing position beyond the allowable range.

According to a first aspect of the present invention, there is provided a printing device that prints predetermined print data on a predetermined sheet of a plurality of labels, a conveying unit that conveys the sheet to the printing unit, and a first unit that runs along the sheet from the printing unit. The first detection means for detecting the position of the label of the paper conveyed by the conveyance means, and a second distance shorter than the first distance from the printing means along the paper. A second detection unit that detects the position of the label of the sheet conveyed by the conveyance unit and one of the first detection unit and the second detection unit according to the conveyance speed of the sheet. And a control means for recognizing the position of the label using the detection result obtained by the above and controlling the timing at which the printing means performs printing on the label.
In the printing apparatus according to the first aspect, the control unit can control the timing at which the printing unit performs printing on the label according to the conveyance speed of the paper and the pitch of the label.
Further, in the printing apparatus according to claim 1, data indicating which detection result of the first detection means or the second detection means should be used in accordance with a combination of the sheet conveyance speed and the label pitch. Storage means for storing can be further provided, and the control means can control the timing at which the printing means performs printing on the label based on the data.

  According to the printing apparatus of the present invention, the two sensors are arranged at a predetermined interval along the paper conveyance path, and the detection result of one of the sensors is selected as appropriate according to the paper conveyance speed or the like. Since it is used, it is possible to suppress detection errors of the amount of movement of the paper and the paper position due to paper flapping, bending, etc., and to prevent the printing position from deviating beyond the allowable range.

  FIG. 1 is a schematic configuration diagram of a thermal printer 100 as an embodiment of the present invention. As shown in the figure, a thermal printer 100 includes a thermal head 5 that prints predetermined print data on the label 1 of a sheet 4 on which a label 1 is releasably stuck on a mount 2, and the sheet 4 is transferred to the thermal head 5. The platen roller 6 that is pressed and rotated toward the thermal head 5 while being sandwiched between the thermal head 5 and the platen roller 6 that is conveyed in a predetermined conveyance direction is disposed at a position separated from the print position of the thermal head 5 by a predetermined distance A. Irradiating predetermined light on the back surface of 2 (the surface to which the label 1 is not attached), receiving the reflected light, and detecting an identification mark such as a black rectangular shape formed on the back surface of the mount 2, A reflective first sensor 7 that outputs a detection signal is disposed at a position away from the first sensor 7 by a predetermined distance B (shorter than the distance A), and irradiates the back surface of the mount 2 with predetermined light. Receive the reflected light A detection mark such as a black rectangular shape formed on the back surface of the paper 2 is detected and output by a reflection-type second sensor 8 that outputs a detection signal and a control unit 10 to be described later. On the other hand, it comprises a stepping motor 9 that transmits a rotational driving force via a gear (not shown) and the like, and a control unit 10 that controls each part and executes various processes. The first sensor 7 and the second sensor 8 irradiate light on the back surface of the mount 2, receive the reflected light, and have a voltage value corresponding to the intensity of the received light (the amount of light received per unit time). A detection signal is output. The thermal head 5, the second sensor 8, and the first sensor 7 are arranged in this order along the conveyance path of the paper 4. That is, when the side closer to the thermal head 5 is the upstream side, the second sensor 8 is disposed on the upstream side, and the first sensor 7 is disposed on the downstream side.

  FIG. 2 is a block diagram illustrating a configuration example of the control unit 10 of FIG. As shown in the figure, the control unit 10 executes various processes in accordance with a control program stored in a ROM (Read Only Memory) 12 (to be described later), and controls a CPU (Central Processing Unit) 11 that controls each unit, ROM 12 for storing programs, various setting data, and the like; RAM 13 for temporarily storing various data necessary for CPU 11 to execute various processes; and RAM 13 for developing print data; and external devices such as personal computers An external interface 14 for controlling transmission / reception of various data such as print data and commands performed between them, an operation unit 16 configured by various buttons and operated when inputting predetermined commands and data, and an operation Interface 1 for supplying a code corresponding to the button operated in the unit 16 to the CPU 11 via the bus 25 An interface 17 for supplying a display signal corresponding to the display data supplied from the CPU 11 to the display unit 18, and a display unit 18 for displaying characters and symbols corresponding to the display data in accordance with the display signal supplied from the interface 17. A motor control unit 19 that supplies a control signal to the stepping motor 9 under the control of the CPU 11 and a print control unit that supplies a control signal corresponding to the print data supplied from the CPU 11 to the thermal head 5 under the control of the CPU 11. 21 and under the control of the CPU 11, a control signal is supplied to the first sensor 7 to drive and control, and detection data corresponding to the detection signal supplied from the first sensor 7 is supplied to the CPU 11 via the bus 25. A control signal is supplied to the second sensor 8 under the control of the first sensor control unit 22 and the CPU 11 to The second sensor control unit 23 that controls and supplies detection data corresponding to the detection signal supplied from the second sensor 8 to the CPU 11 via the bus 25, and the power source such as the table shown in FIG. The flash ROM 24 stores various data to be held, various user setting data, and the like.

  As described above, the stepping motor 9 is driven according to the control signal supplied from the motor control unit 19 and is rotated at a predetermined angular velocity. Further, the thermal head 5 prints characters, figures, and the like corresponding to predetermined print data on the label 1 of the paper 4 in accordance with a control signal supplied from the print control unit 21.

  The paper 4 is conveyed in a predetermined direction by the frictional force generated by the rotation of the platen roller 6 while being pressed against the thermal head 5 by the platen roller 6. However, since the platen roller 6 is repeatedly rotated and stopped, the paper may flutter or bend. For this reason, there are cases where the feeding amount of the paper 4 and the paper position cannot be accurately detected in the vicinity of the thermal head 5. This tendency becomes stronger as the conveying speed becomes faster, and becomes stronger as the paper pitch becomes shorter.

  On the other hand, the second sensor 8 arranged at a position closer to the thermal head 5 (a position away from the print position of the thermal head 5 along the conveyance path of the paper 4 by a distance B) is a position farther from the thermal head 5. The accuracy of the detection signal is higher than that of the first sensor 7 disposed at a position away from the print position of the thermal head 5 along the conveyance path of the paper 4 by a distance A. This is because the amount of movement of the sheet 4 and the position of the sheet 4 can be detected more accurately as it is closer to the thermal head 5 because the sheet 4 may be slightly bent even if there is no flapping or bending. Because. Therefore, it is desirable to use the detection signal of the second sensor 8 as much as possible.

  Therefore, the first sensor 7 disposed at a position away from the thermal head 5 by a predetermined distance A and a predetermined distance shorter than the distance A from the thermal head 5 according to the size of the paper 4 and the conveyance speed. The detection amount of the paper 4 and the paper position are detected by selectively using one of the detection signals of the second sensor 8 arranged at a position separated by the distance B.

  FIG. 3 includes a set of data serving as a reference for determining which detection signal of the first sensor 7 and the second sensor 8 should be selected according to the size of the paper pitch of the paper 4 and the size of the conveyance speed. It is a table. In this example, in each paper 4 having a paper pitch of 9 millimeters (mm), 16 mm, 25 mm, and 37 mm, when the conveyance speed of the paper 4 is 50 mm / second or less, when it is 75 mm / second or less, it is 100 mm / second or less. In each case, it is shown which detection signal of the first sensor 7 and the second sensor 8 should be selected.

  The symbol “◯” in FIG. 3 indicates that the detection signal of the second sensor 8 disposed at a position (distance B) close to the thermal head 5 is selectively used, and the symbol “X” indicates the thermal head 5. It shows that the detection signal of the 1st sensor 7 arrange | positioned in the position (distance A) far from is selectively used.

  That is, when the conveyance speed is 50 mm / second or less, the detection signal of the second sensor 8 is selected regardless of the paper pitch. This is because, when the conveyance speed is relatively low, fluttering and bending that occur during conveyance and when the sheet 4 is stopped are relatively small.

  When the conveyance speed is faster than 50 mm / second and less than 75 mm / second, the detection signal of the second sensor 8 is selected when the paper pitch is 25 mm or more, and the detection signal of the first sensor 7 when the paper pitch is smaller than 25 mm. Is selected.

  Further, when the conveyance speed is faster than 75 mm / second and less than 100 mm / second, the detection signal of the second sensor 8 is used when the paper pitch is 37 mm or more, and the detection signal of the first sensor 7 when the paper pitch is smaller than 37 mm. Is selected.

  FIG. 4 is a view when the paper 4 is viewed from the side (front surface) to which the label 1 is attached. The sheet pitch is represented by the distance from the leading end (or rear end) of the label 1 to the leading end (or rear end) of the next adjacent label 1.

  FIG. 5 is a view when the paper 4 is viewed from the side (back surface) where the label 1 is not attached. The identification mark 3 used when detecting the feed amount and the paper position of the paper 4 is printed on the back surface of the mount 2 corresponding to the position of the front end (or the rear end) of the label 1 attached to the front surface of the mount 2. It is formed by. The shape of the identification mark 3 is, for example, a rectangular shape, and the color is, for example, black. The identification mark 3 is detected by the first sensor 7 and the second sensor 8.

  FIG. 6 is a flowchart showing a procedure in which one of the detection signals of the first sensor 7 and the second sensor 8 is selected according to the paper pitch and the conveyance speed under the control of the control unit 10.

  First, in step S1, the CPU 11 determines whether or not the conveyance speed of the paper 4 is 50 mm / second or less. The conveyance speed of the paper 4 can be estimated from the rotation speed of the stepping motor 9.

  As a result, when it is determined that the conveyance speed of the sheet 4 is 50 mm / second or less, the information is stored in advance in the flash ROM 24 or the like, or is input by the operation unit 16 being input by the user and set in FIG. Based on the data constituting the table as shown, the process proceeds to step S7, and the detection signal of the second sensor 8 is selected. On the other hand, if it is determined that the conveyance speed of the paper 4 is faster than 50 mm / second, the process proceeds to step S2.

  In step S2, it is determined whether or not the conveyance speed of the paper 4 is 75 mm / second or less. As a result, when it is determined that the conveyance speed of the paper 4 is 75 mm / second or less, the process proceeds to step S4. On the other hand, if it is determined that the conveyance speed of the paper 4 is faster than 75 mm / second or less, the process proceeds to step S3.

  In step S4, it is determined whether or not the paper pitch is 25 mm or more. As a result, when it is determined that the paper pitch is 25 mm or more, the process proceeds to step S7, and the detection signal of the second sensor 8 is selected. On the other hand, if it is determined in step S4 that the paper pitch is smaller than 25 mm, the process proceeds to step S6, and the detection signal of the first sensor 7 is selected.

  In step S3, it is determined whether or not the conveyance speed of the paper 4 is 100 mm / second or less. As a result, when it is determined that the conveyance speed of the paper 4 is 100 mm / second or less, the process proceeds to step S5. On the other hand, when it is determined that the conveyance speed of the paper 4 is higher than 100 mm / second, the process proceeds to step S6, and the detection signal of the first sensor 7 is selected.

  In step S5, it is determined whether the paper pitch is 37 mm or more. As a result, when it is determined that the paper pitch is 37 mm or more, the process proceeds to step S7, and the detection signal of the second sensor 8 is selected. On the other hand, if it is determined that the paper pitch is smaller than 37 mm, the process proceeds to step S6, and the detection signal of the first sensor 7 is selected.

  When the process in step S7 or the process in step S6 ends, the process proceeds to step S8, and it is determined whether or not a confirmation button (not shown) of the thermal printer 100 has been operated. If it is determined that the confirm button has been operated, the process is terminated, and thereafter, a print issue process is executed at the selected sensor and transport speed. On the other hand, if it is determined that the confirm button has not been operated, the process returns to step S1, and the processes after step S1 are repeatedly executed.

  As described above, the detection signal with the smaller detection error of the first sensor 7 and the second sensor 8 is selected according to the size of the paper pitch of the paper 4 and the conveyance speed, and the selected detection signal is selected. Based on the signal, the feed amount and the paper position of the paper 4 are obtained, and the print timing of the print data by the thermal head 5 is controlled. Thereby, the error of the printing position on the label 1 of the paper 4 can be suppressed.

  It should be noted that the configuration and operation of the above-described embodiment are examples, and it goes without saying that they can be changed as appropriate without departing from the spirit of the present invention.

  The present invention can be applied not only to a thermal printer, but also to various other printing apparatuses.

1 is a diagram illustrating a schematic configuration example of a thermal printer to which the present invention is applied. It is a block diagram which shows the structural example of the control part of FIG. It is a table consisting of a set of data indicating which detection signal of the first sensor and the second sensor should be selected according to the paper pitch and the conveyance speed. It is a figure which shows the example of a paper. It is a figure which shows the example of the identification mark formed in the back surface of a mount. 5 is a flowchart illustrating a procedure in which a control unit selects a detection signal of one of a first sensor and a second sensor according to the size of a paper pitch and the size of a conveyance speed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Label 2 Mount 3 Identification mark 4 Paper 5 Thermal head 6 Platen roller 7 1st sensor 8 2nd sensor 9 Stepping motor 10 Control part 11 CPU
12 ROM
13 RAM
Reference Signs List 14 External interface 15, 17 Interface 16 Operation unit 18 Display unit 19 Motor control unit 21 Print control unit 22 First sensor control unit 23 Second sensor control unit 24 Flash ROM
25 bus 100 thermal printer

Claims (3)

Printing means for printing predetermined print data on a predetermined sheet of a plurality of labels;
Conveying means for conveying the paper to the printing means;
A first detecting means provided at a point separated from the printing means by a first distance along the paper, and detecting a position of the label of the paper conveyed by the conveying means;
A second detection means provided at a point separated from the printing means by a second distance shorter than the first distance along the paper, and detecting the position of the label of the paper conveyed by the conveyance means; ,
According to the conveyance speed of the paper, the position of the label is recognized using the detection result of either the first detection means or the second detection means, and the printing means And a control means for controlling a timing for performing printing. 2. The printing apparatus according to claim 1, wherein the control unit controls a timing at which the printing unit performs printing on the label according to a conveyance speed of the paper and a pitch of the label. A storage unit for storing data indicating which detection result of the first detection unit and the second detection unit is to be used according to a combination of the conveyance speed of the paper and the pitch of the label;
The printing apparatus according to claim 1, wherein the control unit controls a timing at which the printing unit performs printing on the label based on the data.

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