JP5928560B2 - Paper transport device and printing device - Google Patents

Description

  The present invention relates to a continuous form paper transport apparatus and a printing apparatus having the same.

  In a business printer as a printing apparatus, a folded continuous form with sprocket holes (engagement holes) called fan hold paper is used as a recording medium. The fan hold paper is configured to be cut with a perforation at each page, and is stored in the paper supply unit of the printer in a stacked state in which the perforation is alternately folded in the opposite direction. The fan hold paper is conveyed by a paper conveyance device including a tractor.

  The tractor has a tractor pin (engagement portion) that can be inserted into a sprocket hole (engagement hole) formed along the paper feed direction of the continuous form, and a tractor belt having tractor pins formed on the outer peripheral surface at predetermined intervals. And a drive sprocket and a driven sprocket over which the tractor belt is stretched. The continuous form is set so that the tractor pin is inserted into the sprocket hole. When the continuous form is set, the tractor rotates the drive sprocket by the driving force from the drive source, rotates the tractor belt, and sequentially engages the tractor pins with the sprocket holes of the continuous form, It is conveyed (for example, see Patent Document 1).

  In addition to the tractor described above, the paper transport device for business printers that records information on a continuous form is equipped with a paper feed roller near the print head. Paper is fed by a predetermined feed amount (see, for example, Patent Document 2).

  Conventionally, fan hold paper as a continuous form is generally a carbonless paper that utilizes a color reaction such as leuco dye, or a stack of carbon papers coated with carbon ink on the back of the paper. . For example, when pressure is applied to a carbonless paper or carbon paper by a metal pin of a dot impact head of an impact printer, the pressure portion is colored and information is copied and printed.

JP 2006-232470 A JP 2009-119574 A

  In recent years, the business scope to which business printers are applied has expanded, and for example, there is a demand for printing more information and image information. Therefore, printing with higher accuracy and higher density is desired. In addition, there are various types of recording media, for example, there is a demand to print information on the surface while feeding sheets with a commercial printer in a superposed fan hold form, for example, a sheet made of two different materials such as medicine bags. . Therefore, more accurate paper feeding is desired.

  In the above-described paper transport mechanism, there is a possibility that the paper feed amount of the tractor and the paper feed amount of the paper feed roller may vary due to variations in component accuracy. Further, when two sheets made of materials having different fan holds are overlapped, there is a possibility that the paper feed amount of the paper portion to be printed varies due to a difference in coefficient of friction or a difference in expansion coefficient due to humidity. When the paper feed amount varies, there is a problem that the print quality is deteriorated.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  (Application Example 1) A paper conveying device of a printing apparatus that prints information on a continuous form to be conveyed using a print head, and is engaged with an engagement hole of the continuous form formed along the paper conveying direction. A first transport mechanism having a tractor that sequentially engages a joint portion to transport the continuous form, a first paper feed roller disposed between the first transport mechanism and the print head in the paper transport direction; A second conveying mechanism having a paper pressing roller, a third conveying mechanism having a second paper feeding roller and a second paper pressing roller disposed on the downstream side in the paper conveying direction of the print head, and an actual performance of the first conveying mechanism. A detector for detecting a paper feed amount and a rotation amount of the first paper feed roller of the second transport mechanism, and a paper feed amount per unit time of the first transport mechanism as a reference paper feed amount, Unit of second transport mechanism The paper feed amount per unit time of the first transport mechanism is larger than the paper feed amount per unit time of the first transport mechanism, and the paper feed amount per unit time of the third transport mechanism is the paper feed amount per unit time of the second transport mechanism. The paper holding force of the first transport mechanism is greater than the paper holding force of the second transport mechanism, and the paper holding force of the second transport mechanism is greater than the paper holding force of the third transport mechanism. In addition to being set large, the detector detects the actual paper feed amount of the first transport mechanism and the rotation amount of the first paper feed roller of the second transport mechanism, and the first transport based on the detection result. A paper conveying device characterized by adjusting a paper feeding amount of the mechanism.

  According to this configuration, the paper transport device uses the first transport mechanism as the main feed mechanism, and the first transport mechanism secures a desired paper feed amount and paper feed force with respect to the continuous form, while the second transport mechanism and The third transport mechanism transports the continuous form with a slightly larger paper feed amount in this order. At this time, it is preferable that the difference between the paper feed amount of the first transport mechanism and the paper feed amount of the second transport mechanism is small. Therefore, tension can be applied to the continuous form to be transported in the paper transport path from the first transport mechanism to the third transport mechanism including the printing position. Then, due to the tension, the continuous form is reduced in troubles such as bending, wrinkling, and sagging. As a result, a continuous form can be conveyed with little bending, wrinkles, or sagging.

  Moreover, since the 1st conveyance mechanism is comprised with the tractor, it has big paper holding power. The second transport mechanism and the third transport mechanism have a smaller paper holding force in this order. Therefore, the continuous form is held by the first transport mechanism, and a slight slip can be generated by the second transport mechanism and the third transport mechanism. As a result, the continuous form can be transported in the paper transport apparatus with a desired paper feed amount set by the first transport mechanism. That is, the continuous form can be conveyed with the reference paper feed amount while ensuring a predetermined tension. Therefore, a printing apparatus employing the paper transport device can reduce defective printing due to bending, wrinkling, and sagging of continuous forms, and can ensure paper feeding accuracy and ensure good print quality. be able to.

  Further, the actual paper feed amount of the first transport mechanism and the rotation amount of the first paper feed roller of the second transport mechanism are detected using a detector, and the first transport which is the main feed is based on the detection result. The paper feed amount of the mechanism can be adjusted. Therefore, even if the second transport mechanism has a structure in which slip occurs, the actual paper feed amount and the slip state can be monitored, and when an error occurs with respect to the reference paper feed amount, the first transport mechanism The paper feed amount can be adjusted. As a result, highly accurate paper feeding can be realized.

  Application Example 2 The pressing force of the first paper pressing roller of the second transport mechanism on the first paper feeding roller is the press force of the second paper pressing roller of the third transport mechanism on the second paper feeding roller. The paper conveying device as described above, wherein the paper conveying device is larger than force.

  According to this configuration, the paper holding force of the second transport mechanism can be set larger than the paper holding force of the third transport mechanism.

  Application Example 3 The first transport mechanism and the second transport mechanism are driven by a driving force from one drive source, and the detector is a rotation amount of the first paper feed roller of the second transport mechanism. A rotary encoder for detecting the paper is applied, and the rotary encoder also detects an actual paper feed amount of the first transport mechanism.

  (Application Example 4) The first transport mechanism includes a first drive gear that drives the tractor, and the second transport mechanism includes a second drive gear that drives the first paper feed roller, A motor having a motor gear is applied as a drive source, and the first drive gear, the second drive gear, and the motor gear are stretched by a single toothed belt. apparatus.

  According to these structures, the 1st conveyance mechanism and the 2nd conveyance mechanism can transmit the drive force of the motor which is one drive source directly from a motor gear via a toothed belt. The detector provided on the first paper feed roller of the second transport mechanism can detect the actual paper feed amount of the first transport mechanism and the rotation amount of the first paper feed roller of the second transport mechanism. Therefore, it is possible to monitor the actual paper feed amount and the slip state in the second transport mechanism. As a result, when an error occurs with respect to the reference paper feed amount due to variations in load and slip, the paper feed amount of the first transport mechanism can be adjusted. Therefore, it is possible to realize high-precision paper feeding.

  Application Example 5 The above-described paper transport device, a print head that ejects ink droplets onto a continuous form transported by the paper transport device, a carriage that mounts the print head, and the carriage are provided by the paper transport device. A carriage movement mechanism that reciprocates in a direction orthogonal to the paper conveyance direction.

According to this configuration, the printing apparatus can apply a constant tension to the conveyed continuous form, and can reduce problems such as bending, wrinkling, and sagging of the continuous form. Further, the actual paper feed amount and the slippage state of the second transport mechanism can be monitored, and when the actual paper feed amount has an error with respect to the reference paper feed amount, the error can be eliminated. . Therefore, the printer can reduce printing defects caused by bending, wrinkling, and sagging of continuous forms, and can ensure paper feeding accuracy and realize high-quality printing.
The paper conveying device of the present invention is a paper conveying device of a printing apparatus that prints information on a continuous form to be conveyed by using a print head, and relates to the continuous form formed along the paper conveying direction. A first transport mechanism having a tractor that sequentially engages an engagement portion with the joint hole to transport the continuous form, and a first transport mechanism disposed between the first transport mechanism and the print head in the paper transport direction. A second transport mechanism having a paper feed roller and a first paper presser roller; and a third transport mechanism having a second paper feed roller and a second paper presser roller disposed downstream of the print head in the paper transport direction. The first transport mechanism, the second transport mechanism, and the third transport mechanism are driven by a driving force from a single driving source, and are driven by a rotary encoder provided on the first paper feed roller. A detector for detecting a real paper feed amount of the transport mechanism, and detecting a variation state of rotation of the first paper feed roller of the second transport mechanism based on an output or an output interval of the rotary encoder, A paper feed amount per unit time of the first transport mechanism is a reference paper feed amount, and a paper feed amount per unit time of the second transport mechanism is larger than a paper feed amount per unit time of the first transport mechanism, The paper feed amount per unit time of the third transport mechanism is set larger than the paper feed amount per unit time of the second transport mechanism,
The paper holding force of the first transport mechanism is set larger than the paper holding force of the second transport mechanism, and the paper holding force of the second transport mechanism is set larger than the paper holding force of the third transport mechanism. The detector detects the actual paper feed amount of the first transport mechanism and the rotation variation state of the first paper feed roller of the second transport mechanism, and the paper feed of the first transport mechanism based on the detection result. It is characterized by adjusting the amount.
Further, the paper transport device of the present invention is a power transmission mechanism that transmits the power of the drive source as the paper feed amount per unit time of the first transport mechanism, the second transport mechanism, and the third transport mechanism. It is characterized by being adjusted by.
In the paper transport device of the present invention, the pressing force of the first paper pressing roller of the second transport mechanism against the first paper feed roller is the second pressing force of the second paper pressing roller of the third transport mechanism. It is characterized by being larger than the pressing force against the paper feed roller.
In the paper transport device of the present invention, the first transport mechanism has a first drive gear for driving the tractor, and the second transport mechanism is a second drive gear for driving the first paper feed roller. The drive source is a motor having a motor gear, and the first drive gear, the second drive gear, and the motor gear are stretched by a single toothed belt. To do.
In the paper transport device of the present invention, the continuous form has a two-layer structure of two sheets, and a continuous medicine bag paper in which medicine bag paper which is a bag-like paper for containing medicine is continuously formed. It is characterized by including.
The printing apparatus of the present invention includes the above-described paper transport device, a print head that ejects ink droplets onto a continuous form transported by the paper transport device, a carriage that mounts the print head, and the carriage. A carriage moving mechanism that reciprocates in a direction orthogonal to the paper conveyance direction by the paper conveyance device.

1 is an external perspective view of an ink jet printer. FIG. The figure which shows schematic structure of a paper conveying apparatus. The figure which shows the structure of the power transmission mechanism of a paper conveying apparatus. The figure which shows the example of a continuous form. FIG. 2 is a block diagram illustrating a main configuration of an inkjet printer. The flowchart which shows operation | movement of an inkjet printer.

  Hereinafter, the present embodiment will be described with reference to the drawings. In the drawings referred to in the following description, the vertical and horizontal scales of members or parts may be shown differently from the actual ones for convenience of description and illustration. In this embodiment, an example of an inkjet printer that performs printing by ejecting ink droplets onto a sheet will be described as a printing apparatus.

(Overall configuration of inkjet printer)
First, the overall configuration of the ink jet printer will be described with reference to FIG. FIG. 1 is an external perspective view of an ink jet printer. 1 indicates the paper conveyance direction of the continuous form, the Y direction indicates the width direction of the continuous form, and the Z direction indicates a direction orthogonal to the X direction and the Y direction.

  The inkjet printer 100 according to the present embodiment is a type of business printer that feeds fan hold paper as a continuous form from the rear side of the printer and discharges it to the front side of the printer. As shown in FIG. 1, the ink jet printer 100 accommodates a printer main body 110 (see FIG. 2), which will be described later, in a case 10 constituted by an upper case 11 and a lower case 12. A paper discharge port 14 is opened at the front center of the case 10 in the figure, and a paper supply port 15 is opened at the rear surface in the X direction of the paper discharge port 14. The paper discharge port 14 is provided with a paper discharge tray 16 for receiving a continuous form that has been printed. On both sides of the front surface of the case 10 in the Y direction, there are provided display units 17 made up of LED lamps or the like for displaying the operation state.

  Below the display unit 17 in the Z direction are an ink cover 18a that covers the front of the cartridge storage unit 22a that stores the black ink cartridge 21a, and a cartridge storage unit 22b (see FIG. 2) that stores a plurality of color ink cartridges 21b. An ink cover 18b covering the front is provided on each of the left and right sides. The ink covers 18a and 18b are attached so as to be openable and closable, and the ink cartridges 21a and 21b can be exchanged by opening the ink covers 18a and 18b.

(About printer configuration)
Next, the configuration of the printer main body housed in the case will be described with reference to FIG. FIG. 2 is a perspective view of the printer main body. Note that the X direction, Y direction, and Z direction shown in FIG. 2 are the same as the X direction, Y direction, and Z direction shown in FIG.
As shown in FIG. 2, the printer main body 110 includes an ink supply mechanism 20, a printing mechanism 25, a drainage tank 35, a paper transport device 40, a chassis 50, and a control device 80.

  The ink supply mechanism 20 includes cartridge storage portions 22a and 22b for storing ink cartridges 21a and 21b, an ink pressurization portion (not shown), and an ink supply pipe (not shown). The cartridge storage portions 22a and 22b are provided in the chassis 50 on the back side of the ink covers 18a and 18b, respectively. The ink in the ink cartridges 21a and 21b stored in the cartridge storage units 22a and 22b is pressurized by the ink pressurizing unit and sent to the printing mechanism 25 through the ink supply pipe.

  The printing mechanism 25 includes an inkjet head 26, a carriage 28, a carriage feed mechanism 30, and a maintenance mechanism (not shown). The inkjet head 26 has a plurality of nozzles 27 (see FIG. 3) that discharge ink supplied by the ink supply mechanism 20 as ink droplets, and the nozzles 27 are directed downward in the Z direction in FIG. 2, that is, toward the continuous form side. It is mounted on the carriage 28. The carriage 28 is movably supported by a carriage shaft 29 extending in the paper width direction (Y direction), and is reciprocated in the Y direction by a carriage feed mechanism 30. The carriage feed mechanism 30 includes a carriage motor 32 and a timing belt 33 driven by the carriage motor 32. Since the carriage 28 is fixed to the timing belt 33, the carriage 28 is reciprocated in the paper width direction (Y direction) according to the travel of the timing belt 33.

  The maintenance mechanism includes a wiping unit (not shown) as well as a suction unit (not shown). The maintenance mechanism can make the suction unit and the wiping unit face the inkjet head 26 mounted on the carriage 28 by moving the carriage 28 in the Y direction. The suction unit seals the surface of the nozzle 27 of the inkjet head 26 when it is not in operation to prevent the nozzle 27 from drying, and also serves to suck and remove the thickened ink from the nozzle 27 of the inkjet head 26. The wiping unit plays a role of wiping off dirt adhering to the surface of the nozzle 27 of the inkjet head 26. The drainage tank 35 has a non-woven fabric such as felt and is provided at the lower portion of the printer main body 110 and stores the drained ink sucked by the suction unit.

(About the configuration of the paper transport device)
Here, the configuration of the paper transport device will be described with reference to FIGS. 3 and 4. FIG. FIG. 3 is a diagram illustrating a schematic configuration of the paper conveyance device, and FIG. 4 is a diagram illustrating a configuration of a power transmission mechanism of the paper conveyance device. Note that the X direction, Y direction, and Z direction shown in FIGS. 3 and 4 are the same directions as the X direction, Y direction, and Z direction shown in FIG. In addition, this paper conveyance apparatus conveys the continuous form R which has a sprocket hole (engagement hole).

  As shown in FIG. 3, the paper transport device 40 includes a paper transport path 41, a first transport mechanism 43, a second transport mechanism 53, a third transport mechanism 63, and a power transmission mechanism 70 (see FIG. 4). Is provided. The paper transport path 41 starts from the paper supply port 15 of the ink jet printer 100 and the printer main body 110 shown in FIGS. 1 and 2, and starts from the paper discharge port 14 via the printing position A by the ink jet head 26 of the printing mechanism 25. It is formed so as to extend along the X direction in FIG. A first transport mechanism 43, a second transport mechanism 53, a printing mechanism 25, and a third transport mechanism 63 are sequentially provided from the upstream side to the downstream side along the paper transport path 41.

  The first transport mechanism 43 is provided in the vicinity of the paper supply port 15 and includes a pair of tractors 44. The tractor 44 spans a tractor pin (engagement portion) 45 that can be inserted into the sprocket hole Q1 of the continuous form R, a tractor belt 46 in which the tractor pins 45 are formed at predetermined intervals on the outer peripheral surface, and the tractor belt 46. A driving sprocket 47 and a driven sprocket 48 are provided. The pair of tractors 44 are arranged on both sides in the Y direction of the paper transport path 41 so as to correspond to the sprocket holes Q1 at both ends in the width direction of the continuous form R to be transported. Each of the drive sprockets 47 of the pair of tractors 44 is connected by a drive sprocket shaft 49 so that the pair of tractors 44 are driven in synchronization. A drive gear 42 (see FIG. 4) is attached to the end of the drive sprocket shaft 49 so as to be exposed on one outer surface of the chassis 50.

  The second transport mechanism 53 is provided along the paper transport path 41 between the first transport mechanism 43 and the printing position A by the ink jet head 26, specifically, slightly on the ink jet head 26 side. The second transport mechanism 53 includes a first paper feed roller 55 and a first paper presser roller 58. The first paper feed roller 55 includes a cylindrical roller 56 made of an elastic body such as rubber or a sintered body coated with a granular body, and a roller shaft 57 penetrating the axial direction of the roller 56, and a paper transport path 41. Is provided below the paper transport path 41 in the Z direction.

  A drive gear 52 (see FIG. 4) is attached to one end of the roller shaft 57 so as to be exposed on one outer surface of the chassis 50. The drive gear 52 is mounted with a rotary encoder (detector) 51 (see FIG. 4) for detecting the rotation amount of the first paper feed roller 55 (paper feed amount of the second transport mechanism 53). Yes. The first paper presser roller 58 includes a cylindrically supported cylindrical roller 59 made of an elastic body such as rubber, and the first continuous form R transported through the paper transport path 41 by a biasing force from above in the Z direction. It is arranged so as to be pressed against the paper feed roller 55.

  The third transport mechanism 63 is provided along the paper transport path 41 between the printing position A by the ink jet head 26 and the paper discharge port 14, specifically, slightly on the ink jet head 26 side. The third transport mechanism 63 has a second paper feed roller 65 and a second paper presser roller 68. The second paper feed roller 65 includes a cylindrical roller 66 made of an elastic body such as rubber or a sintered body coated with a granular body, and a roller shaft 67 penetrating in the axial direction of the roller 66. Is provided below the paper transport path 41 in the Z direction. A drive gear 62 (see FIG. 4) is attached to one end of the roller shaft 67 so as to be exposed on one outer surface of the chassis 50.

  The second paper pressing roller 68 is in the form of a so-called jagged roller formed by processing a metal plate into a star shape. The second paper pressing roller 68 transfers the continuous form R conveyed through the paper conveyance path 41 by the urging force from above in the Z direction to the second paper. It arrange | positions so that it may press on the feed roller 65. FIG. A paper detector 78 is installed between the second paper pressing roller 68 and the inkjet head 26. The paper detector 78 is, for example, a reflection type photosensor, and detects the presence or absence and the leading edge or trailing edge of the continuous form R conveyed into the paper conveying path 41 by the paper conveying device 40.

  As shown in FIG. 4, the power transmission mechanism 70 includes a paper feed motor 72 as a drive source having a motor gear 71, a gear group 73, and a toothed belt 74, and is provided on one outer surface of the chassis 50 in the Y direction. Provided. The paper feed motor 72 is fixed to the chassis 50 so that the motor gear 71 is exposed on one outer surface of the chassis 50. As a result, on one outer surface of the chassis 50, the motor gear 71 and the gear group 73 including the drive gear 42, the drive gear 52, and the drive gear 62 described above are arranged. The toothed belt 74 is an internal tooth type endless belt, and is stretched around the motor gear 71, the drive gear 42 of the first transport mechanism 43, and the drive gear 52 of the second transport mechanism 53 with a constant tension. The drive gear 62 of the third transport mechanism 63 is engaged with the drive gear 52 of the second transport mechanism 53. The toothed belt 74 may use a tension roller in order to ensure proper tension.

  In the paper transport device 40 having the above-described configuration, the driving force of the paper feed motor 72 is transmitted from the motor gear 71 via the toothed belt 74 to the drive gear 42 of the first transport mechanism 43 and the drive gear 52 of the second transport mechanism 53. Communicate directly to. Further, it is transmitted to the drive gear 62 of the third transport mechanism 63 via the drive gear 52 of the second transport mechanism 53. The paper feed motor 72 is controlled based on a control signal from a control device 80 described later.

  The paper conveyance device 40 conveys the continuous form R having the sprocket hole Q1 engaged with the tractor pin 45 along the paper conveyance path 41 by rotating the tractor 44 of the first conveyance mechanism 43. The continuous form R transported by the first transport mechanism 43 is drawn between the first paper feed roller 55 and the first paper presser roller 58 that rotate by the second transport mechanism 53, and follows the paper transport path 41. Is further conveyed. The continuous form R transported by the second transport mechanism 53 passes between the printing position A of the printing mechanism 25 and the second paper feed roller 65 and the second paper presser roller 68 that rotate the third transport mechanism 63. The paper is drawn in between and sequentially conveyed in the direction of the paper discharge port 14 along the paper conveyance path 41.

  In the paper transport device 40 of the present embodiment, the first transport mechanism 43 is set as the main transport mechanism. That is, the paper feed amount per unit time by the tractor 44 of the first transport mechanism 43 is set as the reference paper feed amount T1 to be printed by the printing mechanism 25. Then, the paper feed amount per unit time by the first paper feed roller 55 of the second transport mechanism 53 is the paper feed amount T2, and the paper feed amount by the second paper feed roller 65 of the third transport mechanism 63 is the paper feed amount per unit time. When the feed amount T3 is set, a difference is set between the respective paper feed amounts, and the paper feed amount T3> the paper feed amount T2> the reference paper feed amount T1 is set.

  In this case, the drive gear 42 of the first transport mechanism 43 and the drive gear 52 of the second transport mechanism 53 that are rotationally driven by the toothed belt 74, and the third transport that is rotationally driven by the drive gear 52 of the second transport mechanism 53. The number of teeth (reduction ratio) with the drive gear 62 of the mechanism 63 may be adjusted. Further, it may be adjusted by the pitch of the tractor pins 45 formed on the tractor belt 46 and the diameters of the first paper feed roller 55 and the second paper feed roller 65. In this embodiment, for example, the paper feed amount T2 is increased by about 1% and the paper feed amount T3 is increased by about 2.5% with respect to the reference paper feed amount T1. In addition, this numerical value is an illustration and is not limited to this.

  Further, the paper holding force F1 is the paper holding force by the tractor 44 of the first transport mechanism 43, and the paper holding force F2 is the paper holding force of the first paper feed roller 55 and the first paper pressing roller 58 of the second transport mechanism 53. When the paper holding force by the second paper feed roller 65 and the second paper pressing roller 68 of the third transport mechanism 63 is a paper holding force F3, a difference is given by each paper holding force, and the paper holding force F1> paper holding force F2. > Set to be the paper holding force F3. In general, the paper holding force F is determined by the pressing by the pressing roller and the material shape of the pressing roller, and is substantially proportional to the paper feeding force G. At this time, it is preferable to set so that the continuous form R can be sent along the paper transport path 41 with only the paper feed force G1 using the paper feed force G1 by the tractor 44 of the first transport mechanism 43 as a main feed force.

  The paper holding force F1 by the tractor 44 of the first transport mechanism 43 is maximized because the sprocket hole Q1 of the continuous form R is engaged with the tractor pin 45 of the tractor 44. The paper holding force F2 of the second transport mechanism 53 is caused by the pressing (biasing force) of the first paper pressing roller 58 against the first paper feed roller 55, and the paper holding force F3 of the third transport mechanism 63 is changed to the second paper feed roller. It is adjusted by pressing (biasing force) of the second paper pressing roller 68 against 65. In the present embodiment, for example, the paper holding force F2 of the second transport mechanism 53 is set to 1/3 to 1/2 of the paper holding force F3 of the third transport mechanism 63. In addition, this numerical value is an illustration and is not limited to this.

  As described above, the paper conveyance device 40 uses the conveyance by the tractor 44 of the first conveyance mechanism 43 as the main conveyance, and assists the conveyance by the second conveyance mechanism 53 and the third conveyance mechanism 63. Further, in the relationship between the second transport mechanism 53 and the third transport mechanism 63, the third transport mechanism 63 is positioned as an auxiliary to the second transport mechanism 53.

  That is, while the first transport mechanism 43 secures a desired paper feed amount T1 and paper holding force F1 for the continuous form R, the second transport mechanism 53 has a slightly larger paper feed amount T2 than the first transport mechanism 43. To send a continuous form R. However, in the first transport mechanism 43, the continuous form R can apply a constant tension to the continuous form R because the sprocket hole Q1 is engaged with the tractor pin 45 of the tractor 44. Since the paper holding force F2 of the second transport mechanism 53 is smaller than the paper holding force F1 of the first transport mechanism 43, the continuous form R is between the first paper feed roller 55 and the first paper presser roller 58. Slipping occurs and the paper feed amount T1 is kept while maintaining the tension. Accordingly, it is possible to prevent the continuous form R from being bent, wrinkled, or sagging due to the perforation between the first transport mechanism 43 and the second transport mechanism 53.

  Further, the first transport mechanism 43 secures a desired paper feed amount T1 and a paper holding force F1 for the continuous form R, and the second transport mechanism 53 causes the third form to be slipped with respect to the continuous form R. The mechanism 63 sends the continuous form R with a paper feed amount T3 slightly larger than that of the second transport mechanism 53. However, since the sprocket hole Q1 of the continuous form R is engaged with the tractor pin 45 of the tractor 44 in the first transport mechanism 43, the continuous form R receives a certain tension by the third transport mechanism 63. Since the paper holding force F3 of the third transport mechanism 63 is smaller than the paper holding force F2 of the second transport mechanism 53, the continuous form R is between the second paper feed roller 65 and the second paper presser roller 68. Slipping occurs and the paper feed amount T1 is kept while maintaining the tension. As a result, it is possible to prevent bending, wrinkling, and sagging due to the perforation of the continuous form R between the second transport mechanism 53 and the third transport mechanism 63.

(About continuous forms)
Here, a continuous form used in the above-described inkjet printer will be described with reference to FIG. FIG. 5 is a view showing an example of a continuous form, (a) is a view showing one medicine bag paper, (b) is a view showing medicine bag paper as a continuous form, and (c) is a continuous form. It is a figure which shows the fan hold paper. Note that the X direction, Y direction, and Z direction shown in FIG. 5 indicate the same directions as the X direction, Y direction, and Z direction shown in FIG.

  The medicine bag (yakutai) paper 90 is a bag-like paper that accommodates a medicine prescribed in a hospital or a pharmacy and provides the patient with the name of the patient, the kind of medicine, the number of times of taking, etc. on the surface. As shown in FIG. 5A, the medicine bag paper 90 of the present embodiment has a two-layer structure of a transparent synthetic resin film sheet 91 and a paper sheet 92, and has both Y-direction side edges 90a and 90b and an X-direction lower edge. It has a bag shape in which three sides of 90c are bonded with an adhesive and an upper portion 90d in the X direction is opened. In the medicine bag paper 90, necessary items such as a patient name are printed on the paper sheet 92 portion by the above-described inkjet printer 100, and the medicine contained therein can be visually confirmed through the transparent synthetic resin film sheet 91. Yes.

  As shown in FIG. 5B, this medicine bag paper 90 is supplied as a continuous medicine bag paper 90A in which a plurality of medicine bag papers 90 are continuously formed with the above as a set. That is, the synthetic resin film sheet 91 and the paper sheet 92 are one continuous long sheet 91a and 92a, respectively, and both side edges 90a and 90b are bonded with an adhesive and both side edges along the X direction. Sprocket holes Q1 to which the tractor pins 45 shown in FIG. 3 can be engaged are formed in rows 90a and 90b at a predetermined pitch. These long sheets 91a and 92a are configured to be separable one by one by a perforation (separation part) 94 provided at a predetermined interval in the longitudinal direction (X direction). One side of each perforation 94 is bonded with an adhesive along the width direction. This adhesion portion corresponds to the lower edge 90c. The continuous medicine bag paper 90A is alternately folded at the perforation 94 and has a so-called fan hold shape. Since the continuous medicine bag paper 90A has such a form, it can be fed and continuously printed by the ink jet printer 100 having the tractor 44.

  The continuous form R used in the inkjet printer 100 is not limited to the above-described continuous medicine bag paper 90A. As shown in FIG. 5 (c), sprocket holes Q1 are formed in rows at a predetermined pitch along the X direction on both side edges 96a and 96b of the paper in the Y direction, and at a predetermined interval in the X direction. Ordinary fan hold paper configured to be separable one by one by the provided perforation 94 may be used.

(Control of inkjet printer)
Next, the control system of the ink jet printer will be described with reference to FIG. FIG. 6 is a block diagram showing the main configuration of the inkjet printer. As shown in FIG. 6, the ink jet printer 100 includes a printing mechanism 25 having an ink jet head 26, a carriage feeding mechanism 30 having a carriage motor (not shown), a paper transport device 40, and a paper feed amount detector (rotary encoder) 51. A printer main body 110 having a unit 79 and a control device 80 that performs overall control thereof are provided.

  The control device 80 includes a control unit 81 that is a main part of the control system, a head driver 82 that drives and controls the inkjet head 26, a motor driver 84 that drives the ink supply mechanism 20, the paper transport device 40, and the carriage feed mechanism 30. The interface unit 85 is provided. The control unit 81 includes a CPU (Central Processing Unit) 86, an information processing unit 87, and a storage unit 88. The CPU 86 executes various processes such as an input signal process from an operation system and a detection system (not shown) and a printing process. The information processing unit 87 processes various information.

  The storage unit 88 includes a RAM (Random Access Memory), a ROM (Read Only Memory), and the like (not shown). The RAM temporarily stores various data such as print data input from the host computer 89 via the interface unit 85, and temporarily develops a program such as print processing executed by the CPU 86. Here, the print data indicates a pattern to be printed on the continuous form R by the inkjet head 26.

  The head driver 82 controls the inkjet head 26 based on a command from the CPU 86. The motor driver 84 individually controls the motors of the paper transport device 40 and the carriage feed mechanism 30 based on commands from the CPU 86. The interface unit 85 outputs the print data received from the host computer 89 to the control unit 81 and outputs various information received from the control unit 81 to the host computer 89.

  The ink jet printer 100 having the above-described structure is a paper transporting operation that transports the continuous medicine bag paper 90A by a predetermined paper transport amount in the X direction shown in FIG. The continuous medicine bag paper 90A is printed while alternately performing a printing operation in which printing is performed by reciprocating in the Y direction perpendicular to the direction. The printed medicine bag paper 90 is separated and issued one by one by the perforation 94.

(Operation of inkjet printer)
Next, the operation of the above-described ink jet printer, in particular, a continuous form conveyance method will be described with reference to FIG. FIG. 7 is a flowchart showing the operation of the ink jet printer. As shown in FIG. 7, the operation of the ink jet printer 100 includes a paper setting step S1, a first paper transport step S2, a paper feed calculation step S3, a paper feed determination step S4, a paper feed amount correction step S5, It has 2nd paper conveyance process S6 and printing process S7. In the following description, a case where the continuous medicine bag paper 90A is applied as the continuous form R will be described as an example.

  In the paper setting step S1 shown in FIG. 7, the continuous medicine bag paper 90 </ b> A shown in FIG. 5B is set on the paper conveyance device 40 of the inkjet printer 100. Specifically, the sprocket holes Q1 formed on both side edges 90a and 90b of the continuous medicine bag paper 90A are engaged with the tractor pin 45 formed on the tractor belt 46 of the tractor 44 as the first transport mechanism 43. At this time, it is preferable that the leading end portion of the continuous medicine bag paper 90 </ b> A is set in the vicinity of the first paper feed roller 55 and the first paper presser roller 58 of the second transport mechanism 53.

  In the first paper transporting step S2, the paper feed motor 72 is driven based on a control signal from the motor driver 84 of the control unit 81 shown in FIG. 6, and the motor gear 71 shown in FIG. Driving force is transmitted to the drive gear 42 of the first transport mechanism 43 and the drive gear 52 of the second transport mechanism 53. The driving force is transmitted to the driving gear 62 of the third transport mechanism 63 via the driving gear 52 of the second transport mechanism 53. By doing so, the tractor pin 45 formed on the tractor belt 46 by rotating the tractor belt 46 is sequentially engaged with the sprocket hole Q1 of the continuous medicine bag paper 90A, and the continuous medicine bag paper 90A is transferred to the paper transport path. 41 is conveyed.

  The continuous medicine bag paper 90 </ b> A transported along the paper transport path 41 reaches the second transport mechanism 53. The continuous medicine bag paper 90A that has reached the second transport mechanism 53 is transported by the rotating first paper feed roller 55 and the first paper presser roller 58 of the second transport mechanism 53, and passes the printing position A by the ink jet head 26. Then, it reaches the third transport mechanism 63. The continuous medicine bag paper 90 </ b> A that has reached the third transport mechanism 63 is transported toward the paper discharge port 14 by the second paper feed roller 65 and the second paper presser roller 68 that are rotated by the third transport mechanism 63. That is, the continuous medicine bag paper 90 </ b> A is moved along the paper transport path 41, the tractor 44 of the first transport mechanism 43, the first paper feed roller 55 and the first paper presser roller 58 of the second transport mechanism 53, and the third transport. A sheet feeding force is obtained from the second sheet feeding roller 65 and the second sheet pressing roller 68 of the mechanism 63 and conveyed.

  The continuous medicine bag paper 90 </ b> A to be conveyed is detected by the paper detector 78 disposed in the vicinity of the second paper feed roller 65, and the first paper feed roller 55, the first paper presser roller 58, and the third transport. The mechanism 63 is temporarily stopped while being sandwiched between the second paper feed roller 65 and the second paper pressing roller 68 of the mechanism 63.

  In the paper feed calculation step S3 shown in FIG. 7, the continuous medicine bag paper 90A in the first paper transport step S2 is mounted on the drive gear 52 of the first paper feed roller 55 of the second transport mechanism 53 shown in FIG. The amount of rotation of the first paper feed roller 55 is detected by the rotary encoder 51. Further, as described above, the drive gear 42 of the first transport mechanism 43 and the drive gear 52 of the second transport mechanism 53 are stretched by the toothed belt 74 together with the motor gear 71 shown in FIG. Therefore, the rotary encoder 51 calculates the actual paper feed amount Ta at the tractor 44 of the first transport mechanism 43, that is, the actual paper feed amount Ta at the paper transport device 40. Further, from the output or output interval of the rotary encoder 51, it is possible to know the variation state (rotation state) of the rotation of the first paper feed roller 55 on which the continuous medicine bag paper 90A is conveyed while sliding. This calculation calculation is performed by the control unit 81 of the control device 80 shown in FIG.

  In the paper feed determination step S4 shown in FIG. 7, the difference between the actual paper feed amount Ta calculated in the paper feed calculation step S3 and the set paper feed amount Tb stored in the storage unit 88 of the control unit 81 is compared. Is calculated. Further, the information processing unit 87 determines whether or not the difference is within an allowable range. It is determined whether or not the variation state of the rotation of the first paper feed roller 55 is within an allowable range. When the difference and the variation state are within the allowable range (YES), the process proceeds to the printing step S7. When the difference and the variation state are larger than the allowable range (NO), the process proceeds to the paper feed amount correction step S5.

  In the paper feed amount correction step S5, the paper feed amount of the paper transport device 40 is corrected so that the difference and variation calculated in the paper feed determination step S4 can be eliminated at the next paper feed. As described above, the paper feed amount of the paper transport device 40 is based on the paper feed amount T1 of the tractor 44 of the first transport mechanism 43. When a difference larger than the allowable range is detected, the paper feed motor 72 is driven by the control signal from the motor driver 84 of the control unit 81 shown in FIG. 6, that is, the tractor belt 46 of the tractor 44 of the first transport mechanism 43 is detected. By controlling the movement amount, the paper feed amount of the continuous medicine bag paper 90A is corrected so that the difference can be eliminated. Further, when the variation state of the rotation of the first paper feed roller 55 is significantly outside the allowable range, it is determined that an abnormality such as an overload is applied to the continuous medicine bag paper 90A. Take the response artificially.

  In the second paper transport step S6 shown in FIG. 7, the paper feed amount Tc corrected in the paper feed amount correction step S5, more specifically, the preset set paper feed amount Tb corresponds to the calculated difference. Paper is fed by adding or subtracting the feed amount. And it progresses to printing process S7.

  In the printing step S7, the ink jet head 26 is moved onto the surface of the continuous medicine bag paper 90A conveyed by the paper conveying device 40 while the ink jet head 26 is reciprocated in the Y direction orthogonal to the paper conveying direction by the carriage feeding mechanism 30 of the printing mechanism 25. Ink is ejected from the nozzles 27 as ink droplets to print information such as characters and images. Then, when the printing of one medicine bag paper 90 is completed, the process proceeds to the end determination step S8.

  In the end determination step S8, it is determined whether there is a medicine bag paper 90 to be printed next. If there is no medicine bag paper 90 to be printed next (NO), the operation of the ink jet printer is terminated. If there is a medicine bag paper 90 to be printed next (YES), the process proceeds to the paper feed calculation step S3 described above. In the paper feed calculation step S3, the above-described operation is performed in the transport of the continuous medicine bag paper 90A in the printing step S7, the process proceeds to the paper feed amount determination step S4, and the same operation as above is repeated.

The effects of this example will be described below.
(1) The paper transport device 40 described above includes a first paper feed roller 55 and a first paper presser roller 58 with a push tractor feed (transport) by the tractor 44 of the first transport mechanism 43 as a main transport. Transport by the third transport mechanism 63 including the second transport mechanism 53 and the second paper feed roller 65 and the second paper press roller 68 is assisted. Further, in relation to the paper feed amount T and the paper holding force F of each transport mechanism, the paper feed amount T3 of the third transport mechanism 63> the paper feed amount T2 of the second transport mechanism 53> the reference paper of the first transport mechanism 43. The feed amount T1 and the paper holding force F1 of the first transport mechanism 43> the paper holding force F2 of the second transport mechanism 53> the paper holding force F3 of the third transport mechanism 63 are set.

  Therefore, the second transport mechanism 53 and the third transport mechanism 63 each slightly increase the paper feed while ensuring the desired paper feed amount T1 and the paper holding force F1 for the continuous medicine bag paper 90A by the first transport mechanism 43. The continuous medicine bag paper 90A is sent in the amounts T2 and T3. As a result, in the paper transport path 41 of the third transport mechanism 63 from the first transport mechanism 43 including the printing position A, tension is applied to the transported continuous medicine bag paper 90A, and bending, wrinkles, and slack are generated due to perforations. Can be prevented. Therefore, the continuous medicine bag paper 90A can be transported in a state where there is little bending, wrinkling or sagging. The ink jet printer 100 that employs the paper transport device 40 can reduce printing defects due to paper folding, wrinkles, and sagging, and can ensure good print quality.

  (2) In the paper transport device 40 described above, the paper transport amount T3 of the third transport mechanism 63> the paper transport amount T2 of the second transport mechanism 53> the reference paper of the first transport mechanism 43 also in relation to the paper transport amount T. The feed amount is T1. However, in relation to the paper holding force F, that is, the holding force of the first and second paper pressing rollers, the paper holding force F1 of the first transport mechanism 43> the paper holding force F2 of the second transport mechanism 53> the third transport mechanism 63. Paper holding force F3. Therefore, the continuous medicine bag paper 90 </ b> A is slipped by the second transport mechanism 53 and the third transport mechanism 63 having a slightly large paper feed amount T while holding the desired paper feed amount T <b> 1 by the tractor 44 of the first transport mechanism 43. It is possible to secure a desired paper feed amount T1 while obtaining tension as a whole. As a result, variations in the paper feed amount T can be reduced. The ink jet printer 100 that employs the paper transport device 40 can ensure paper feeding accuracy and can ensure good print quality.

  (3) The paper transport device 40 described above can transport the continuous form R along the paper transport path 41 while applying a constant tension. Therefore, not only normal perforated fan hold paper, but also continuous form R composed of a plurality of different materials such as thick fan hold paper composed of a large number of sheets or continuous medicine bag paper 90A. However, problems such as bending, wrinkling, and sagging can be reduced and stable paper feeding can be performed.

  (4) In the paper transport device 40 described above, the encoder 51 causes the actual paper feed amount Ta in the tractor 44 of the first transport mechanism 43, that is, the actual paper feed amount Ta in the paper transport device 40, and the first paper feed roller. 55 rotational states can be detected. Therefore, even if the second transport mechanism 53 has a structure in which slippage occurs, the actual paper feed amount Ta and the slip state can be monitored, and when an error occurs with respect to the reference paper feed amount T1, The paper feed amount of the one transport mechanism 43 can be adjusted. As a result, the paper feeding accuracy of the inkjet printer 100 can be ensured.

  As mentioned above, although the Example of this invention was described, various deformation | transformation can be added with respect to the said Example in the range which does not deviate from the meaning of this invention. For example, modifications other than the above embodiment are as follows.

(First modification)
In the above embodiment, in the first paper transport step S2 or the printing step S7, the rotation amount of the first paper feed roller 55 of the second transport mechanism 53 is detected to calculate the actual paper feed amount Ta, and the next medicine bag paper 90 Although the case where the paper feed amount T is corrected at the time of printing is described, the present invention is not limited to this. During the printing operation of one medicine bag paper 90, a paper feed amount calculation step S3, a paper feed amount determination step S4, and a paper feed amount correction step S5 may be performed. That is, for example, the paper feed amount calculation step S3 and the paper feed amount determination step S4 are performed in the paper conveyance for one line or between the lines, and the difference between the actual paper feed amount Ta and the set paper feed amount Tb is allowed. If it is larger than the range, the paper feed amount may be corrected in the paper feed amount correction step S5 to print the next line. In this case, the paper feeding accuracy of the inkjet printer 100 can be further improved.

(Second modification)
In the above-described embodiment, the case where the toothed belt 74 that is an internal tooth type endless belt is applied as the power transmission mechanism 70 is described, but the present invention is not limited to this. A normal gear train may be used. In addition, the ink jet printer 100 has been described as an example of the printer, but is not limited thereto. The printer may be a dot impact printer, a solid font type impact printer, or a thermal printer.

  DESCRIPTION OF SYMBOLS 10 ... Case, 20 ... Ink supply mechanism, 25 ... Printing mechanism, 26 ... Inkjet head, 27 ... Nozzle, 30 ... Carriage feed mechanism, 40 ... Paper conveyance apparatus, 41 ... Paper conveyance path, 42, 52, 62 ... Drive gear , 43 ... 1st conveyance mechanism, 44 ... Tractor, 45 ... Tractor pin, 51 ... Rotary encoder, 53 ... 2nd conveyance mechanism, 55 ... 1st paper feed roller, 58 ... 1st paper press roller, 63 ... 3rd conveyance Mechanism: 65 ... second paper feed roller, 68 ... second paper press roller, 70 ... power transmission mechanism, 71 ... motor gear, 74 ... toothed belt, 79 ... detection unit, 80 ... control device, 81 ... control unit, 82 ... Head driver, 84 ... Motor driver, 90 ... Medicine bag paper, 90A ... Continuous medicine bag paper, 94 ... Perforation, 100 ... Inkjet printer, 110 ... Linters body, A ... printing position, F ... sheet holding force, G ... paper feeding force, T ... paper feed amount, R ... continuous business form.

Claims (7)

A paper conveying device of a printing apparatus that prints information on a continuous form to be conveyed using a print head,
A first transport mechanism having a tractor that sequentially engages an engagement portion with an engagement hole of the continuous form formed along the paper transport direction and transports the continuous form;
A second transport mechanism having a first paper feed roller and a first paper pressing roller disposed between the first transport mechanism and the print head in the paper transport direction;
A third transport mechanism having a second paper feed roller and a second paper presser roller disposed downstream of the print head in the paper transport direction ;
Among the first transport mechanism, the second transport mechanism, and the third transport mechanism, the first paper feed roller included in the second transport mechanism that is secondly arranged toward the downstream side in the paper transport direction. A provided rotary encoder;
The actual paper feed amount of the first transport mechanism is detected by the rotary encoder provided in the first sheet feed roller, also feed the first sheet of the second conveyance mechanism by the output or output interval of the rotary encoder A detector for detecting a variation state of rotation of the roller,
The first transport mechanism, the second transport mechanism, and the third transport mechanism are driven by receiving a driving force from a single drive source,
The paper feed amount per unit time of the first transport mechanism is a reference paper feed amount, and the paper feed amount per unit time of the second transport mechanism is larger than the paper feed amount per unit time of the first transport mechanism. The paper feed amount per unit time of the third transport mechanism is set larger than the paper feed amount per unit time of the second transport mechanism,
The paper holding force of the first transport mechanism is set larger than the paper holding force of the second transport mechanism, and the paper holding force of the second transport mechanism is set larger than the paper holding force of the third transport mechanism. ,
The detector detects the actual paper feed amount of the first transport mechanism and the rotation variation state of the first paper feed roller of the second transport mechanism, and the paper feed amount of the first transport mechanism based on the detection result. A paper conveying device characterized by adjusting the angle. The first transport mechanism includes a drive sprocket on which a tractor belt provided with the engagement portion is bridged, and a first drive gear provided on a rotation shaft of the drive sprocket, and the second transport mechanism is A paper feed motor having a second drive gear provided on a rotation shaft of the first paper feed roller and functioning as the first drive gear, the second drive gear, and the one drive source The motor gear provided on the drive shaft is driven synchronously via a belt spanned around these gears, and is provided on the rotary shaft of the second paper feed roller of the third transport mechanism. The paper conveying apparatus according to claim 1 , wherein the third driving gear is driven in synchronization via the second driving gear of the second conveying mechanism and a speed reduction mechanism . The paper feed amount per unit time of the first transport mechanism, the second transport mechanism, and the third transport mechanism is adjusted by a power transmission mechanism that transmits power of the drive source. Item 3. A paper conveying apparatus according to item 1 or 2 . The pressing force of the first paper pressing roller of the second transport mechanism on the first paper feeding roller is greater than the pressing force of the second paper pressing roller of the third transport mechanism on the second paper feeding roller. The paper conveyance device according to any one of claims 1 to 3, wherein the paper conveyance device is characterized. The first transport mechanism has a first drive gear that drives the tractor,
The second transport mechanism has a second drive gear that drives the first paper feed roller,
The drive source is a motor having a motor gear,
The paper conveying apparatus according to claim 1, wherein the first driving gear, the second driving gear, and the motor gear are stretched by a single toothed belt. The continuous form is
It has a two-layer structure of two sheets, any one of claims 1 to 5 bag is a bag-like sheet containing medicament paper characterized in that it comprises a continuous bag paper formed continuously The paper conveying apparatus as described in the item. A paper conveying device according to any one of claims 1 to 6 ;
A print head for ejecting ink droplets onto a continuous form conveyed by the paper conveying device;
A carriage carrying the print head;
A printing apparatus comprising: a carriage moving mechanism that reciprocates the carriage in a direction orthogonal to a paper conveyance direction by the paper conveyance device.

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