JP2019064767A - Transport device - Google Patents

Abstract

To provide a transport device capable of improving the transmission accuracy of a transport speed of a transported object to a downstream apparatus.SOLUTION: A printer 3 comprises a transport roller 51 that transports a web W toward a winder 4, a transport motor 52 that rotates the transport roller 51, an encoder that outputs an encoder pulse signal in response to a rotation of a motor shaft of the transport motor 52, and a printer control section 33 that counts the number of pulses of an encoder pulse signal, produces as a transport-speed pulse signal a pulse signal logic-inverted in timing of each prescribed count value, and outputs the generated transport-speed pulse signal to the winder 4. The number of output pulses of the encoder per one rotation of the motor shaft of the transport motor 52 and a predefined count value are set such that errors in the resolution of the transport-speed pulse signal relative to the predefined resolution become a threshold or lower.SELECTED DRAWING: Figure 1

Description

  BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a transfer device for transferring a transferred object to a downstream device.

  A printing apparatus for printing an image on a web while conveying a long web as a printing medium; and a winding apparatus connected to the downstream side of the printing apparatus in the conveyance direction of the web and for winding the web printed by the printing apparatus Printing systems are known.

  In the printing system as described above, in order to cause the downstream winding device to operate in synchronization with the printing device, the transport speed of the web as the transported object in the printing device is transmitted to the winding device.

  Here, it is known that, as conveyance speed information indicating the conveyance speed of the printing medium in the printing apparatus, a pulse signal output by an conveyance roller for conveying the printing medium or an encoder connected to a rotary shaft of a motor for driving the conveyance roller is used. (See, for example, Patent Document 1).

  Therefore, in the printing system described above, a pulse signal output by an encoder connected to a conveyance roller for conveying the web by the printing apparatus or a rotary shaft of a motor for driving the conveyance roller is output to the winding apparatus as conveyance speed information. Has been done. At this time, the pulse signal is transmitted as the transport speed information by setting the resolution (the number of pulses per inch) of the pulse signal to a predetermined resolution determined in advance.

JP, 2016-60552, A

  The resolution of the pulse signal output by the above-described encoder is determined according to the diameter of the transport roller and the number of output pulses for one rotation of the rotation shaft. Since the diameter of the transport roller is often predetermined, the encoder is designed such that the number of output pulses for one rotation of the rotating shaft corresponds to the specified resolution at the diameter of the transport roller.

  However, the number of output pulses of the encoder for one rotation of the rotation axis is limited to an integer value. For this reason, an error with respect to the defined resolution may occur in the resolution of the pulse signal output from the encoder. As a result, the transmission accuracy of the transport speed of the web from the printing device to the take-up device may be reduced by the pulse signal.

  As another method of transmitting the conveyance speed from the printing apparatus to the take-up apparatus by the pulse signal, in the printing apparatus, the pulse signal of the encoder is converted into a pulse signal of defined resolution using a device such as a microcomputer having a timer and wound. There is a method of outputting to the take-out device. In this method, the transport speed of the web is calculated from the pulse signal of the encoder using a timer in the device, and based on the result, a pulse signal of defined resolution is generated.

  However, in this method, it takes time to calculate the transport speed of the web, and the transfer of the transport speed to the winding device may be delayed. That is, even with this method, the transmission accuracy of the web transport speed from the printing device to the winding device may be lowered.

  This invention is made in view of the above, and an object of this invention is to provide the conveying apparatus which can improve the transmission accuracy of the conveyance speed of the to-be-conveyed object to a downstream apparatus.

  In order to achieve the above object, according to the transport device of the present invention, a transport mechanism that transports the transported object toward the downstream apparatus by the rotational drive of the rotary body, and the rotation of the rotation shaft that rotates when the rotary body rotates. An encoder for outputting an encoder pulse signal, and counting the number of pulses of the encoder pulse signal, and performing a logic inversion of the pulse signal logically inverted at each specified count value with a transport speed indicating the transport speed of the transported object by the transport mechanism. And a controller for generating the carrier speed pulse signal generated as a pulse signal and generating the generated carrier speed pulse signal to the downstream device, wherein the number of output pulses of the encoder for one rotation of the rotation shaft and the prescribed count value are the carrier speed. It is characterized in that the error with respect to the defined resolution of the resolution of the pulse signal is set to be equal to or less than a threshold.

  According to the transfer device of the present invention, it is possible to improve the transmission accuracy of the transfer speed of the transferred object to the downstream device.

FIG. 1 is a schematic configuration diagram of a printing system according to an embodiment. It is a control block diagram of a printing system shown in FIG. It is explanatory drawing of the method to produce | generate a conveyance speed pulse signal from an encoder pulse signal. It is a figure which shows the example of calculation of the various values for determining the combination of a motor-shaft 1 rotation pulse number and prescription | regulation count value. It is a flowchart of adjustment processing of a conveyance speed pulse signal. It is explanatory drawing of adjustment processing of a conveyance speed pulse signal.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts or components are denoted by the same or equivalent reference numerals throughout the drawings.

  The embodiment shown below exemplifies an apparatus etc. for embodying the technical idea of this invention, and the technical idea of this invention is the material, shape, structure, arrangement etc. of each component. Does not specify the following. Various changes can be added to the technical idea of the present invention within the scope of the claims.

  FIG. 1 is a schematic configuration diagram of a printing system provided with a printing apparatus including a transport apparatus according to an embodiment of the present invention. FIG. 2 is a control block diagram of the printing system shown in FIG. In the following description, top, bottom, left, and right of the paper surface in FIG. Further, the direction orthogonal to the sheet of FIG. 1 is referred to as the front-rear direction.

  As shown in FIGS. 1 and 2, a printing system 1 according to the present embodiment includes an unwinding device 2, a printing device 3, and a winding device (corresponding to the downstream device in the claims) 4.

  The unwinding device 2 unwinds the web (corresponding to the conveyed object in the claims) W from the web roll 6 and transports it to the printing device 3. The web roll 6 is formed by rolling a web W, which is a long printing medium made of paper, film or the like, into a roll. The unwinding device 2 includes a web roll support shaft 11, a pair of delivery rollers 12, buffers 13 and 14, an unwinding motor 15, a delivery motor 16, motor drivers 17 and 18, and speed reducers 19 and 20. And an unwinding device control unit 21.

  The web roll support shaft 11 rotatably supports the web roll 6.

  The pair of delivery rollers 12 convey the web W unwound from the web roll 6 toward the printing apparatus 3 while nipping the web W. One delivery roller 12 of the pair of delivery rollers 12 is rotationally driven by the delivery motor 16, and the other delivery roller 12 is driven to rotate by one delivery roller 12. The pair of delivery rollers 12 is disposed to the right of the web roll support shaft 11.

  The buffer unit 13 is configured to store the slack portion of the web W between the web roll support shaft 11 and the delivery roller 12. The buffer unit 13 includes support rollers 23 and 24 and a dancer roller 25.

  The support rollers 23, 24 support the web W between the web roll 6 and the delivery roller 12. The support rollers 23 and 24 are disposed at the same height apart from each other in the left-right direction.

  The dancer roller 25 pushes down the web W by its own weight between the support rollers 23 and 24. As a result, the slack of the web W between the web roll 6 and the delivery roller 12 is absorbed by the buffer unit 13. The dancer roller 25 moves up and down due to the fluctuation of the amount of slack of the web W between the web roll support shaft 11 and the delivery roller 12.

  The buffer unit 14 stores a slack portion of the web W between the delivery roller 12 and a guide roller 36 of the printing apparatus 3 described later. The buffer unit 14 includes support rollers 26 and 27 and a lift suppressing unit 28.

  The support rollers 26 and 27 support the web W while holding the slack of the web W between the delivery roller 12 and the guide roller 36. The support rollers 26 and 27 are disposed at the same height apart from each other in the left-right direction.

  The floating suppressing portion 28 suppresses floating due to fluctuation of the behavior of the web W between the support rollers 26 and 27.

  The unwinding motor 15 rotates the web roll support shaft 11. When the unwinding motor 15 rotates the web roll support shaft 11 in the clockwise direction in FIG. 1, the web roll 6 rotates in the same direction, and the web W is unwound downstream (right side).

  The delivery motor 16 rotationally drives one delivery roller 12 of the pair of delivery rollers 12.

  The motor drivers 17 and 18 drive the unwinding motor 15 and the feeding motor 16, respectively.

  The reduction gear 19 transmits the rotation of the motor shaft of the unwinding motor 15 to the web roll support shaft 11 at a predetermined reduction ratio. The reduction gear 20 transmits the rotation of the motor shaft of the delivery motor 16 to one delivery roller 12 at a predetermined reduction ratio.

  The unwinding device control unit 21 controls the operation of each part of the unwinding device 2. The unwinding device control unit 21 includes a CPU, a memory, and the like.

  The printing device 3 prints an image on the web W while conveying the web W unwound from the web roll 6 by the unwinding device 2. The printing device 3 is disposed on the downstream side (right side) of the unwinding device 2 in the transport direction of the web W. The printing apparatus 3 includes a conveyance unit 31, printing units 32A and 32B, and a printing apparatus control unit (corresponding to a control unit in the claims) 33. The conveyance unit 31 and the printing apparatus control unit 33 constitute a conveyance apparatus.

  The transport unit 31 transports the web W unwound from the web roll 6 by the unwinding device 2. The conveyance unit 31 includes guide rollers 36 to 45, twenty head lower rollers 46, a meander control unit 47, a pair of brake rollers 48, a brake unit 49, a brake driver 50, and a pair of conveyance rollers (claims And the conveyance motor 52, the motor driver 53, the decelerators 54 and 55, the encoder 56, the buffer unit 57 (corresponding to the storage unit in the claims), and the dancer roller position sensor 58. Equipped with The conveyance roller 51, the conveyance motor 52, and the reduction gear 55 constitute a conveyance mechanism in the claims.

  The guide rollers 36, 37 guide the web W between the unwinding device 2 and the meander control unit 47. The guide roller 36 is disposed at the lower left end of the printing apparatus 3. The guide roller 37 is disposed below the guide roller 36 with the brake roller 48 interposed therebetween.

  The guide rollers 38 to 44 guide the web W between the meander control unit 47 and the conveyance roller 51. The guide roller 38 is disposed slightly above the left side of the meander control roller 60 of the meander control unit 47 described later. The guide roller 39 is disposed above the guide roller 38. The guide roller 40 is disposed to the right of the guide roller 39 at the same height as the guide roller 39. The guide roller 41 is disposed below the guide roller 40 and higher than the guide roller 38. The guide roller 42 is disposed to the left of the guide roller 41 and in the vicinity of the right side of the web W between the guide rollers 38 and 39 and at a position substantially the same height as the guide roller 41. The guide roller 43 is disposed at the lower right of the guide roller 42. The guide roller 44 is disposed below and slightly to the right of the guide roller 43.

  The guide roller 45 guides the web W between the transport roller 51 and the buffer unit 57. The guide roller 45 is disposed to the right of the guide roller 44 with the transport roller 51 interposed therebetween.

  The head lower roller 46 supports the web W under a head unit 64 described later between the guide rollers 39 and 40 and between the guide rollers 41 and 42. Ten head lower rollers 46 are disposed between the guide rollers 39 and 40 and between the guide rollers 41 and 42, respectively. The two head lower rollers 46 are disposed immediately below each head unit 64.

  The meandering control unit 47 corrects meandering, which is a change in position in the width direction (front-rear direction) of the web W. The meander control unit 47 includes meander control rollers 59 and 60.

  The meandering control rollers 59 and 60 guide the web W and correct the meandering of the web W. The meandering control rollers 59 and 60 are rotated by a motor (not shown) so as to be inclined with respect to the width direction of the web W when viewed from the left and right direction, thereby moving the web W in the width direction to correct the meandering. The meandering control roller 59 is disposed to the right of the guide roller 37. The meandering control roller 60 is disposed above the meandering control roller 59.

  The pair of brake rollers 48 nip the web W, and brakes the web W conveyed by the braking force of the brake unit 49.

  The brake unit 49 applies tension to the web W between the transport roller 51 and the brake roller 48 by applying a brake to the web W via the brake roller 48. The brake unit 49 is, for example, a powder brake.

  The brake driver 50 drives the brake unit 49.

  The pair of transport rollers 51 transports the web W toward the winding device 4 while nipping the web W. One of the conveyance rollers 51 of the pair of conveyance rollers 51 is rotationally driven by the conveyance motor 52, and the other conveyance roller 51 is rotated by the one conveyance roller 51. The pair of conveyance rollers 51 is disposed between the guide rollers 44 and 45.

  The conveyance motor 52 rotationally drives one of the conveyance rollers 51 of the pair of conveyance rollers 51.

  The motor driver 53 drives the conveyance motor 52.

  The speed reducer 54 transmits the rotation of one of the pair of brake rollers 48 to the output shaft of the brake unit 49 at a predetermined reduction ratio. The reduction gear 55 transmits the rotation of the motor shaft of the conveyance motor 52 to one of the conveyance rollers 51 at a predetermined reduction ratio.

  The encoder 56 is provided on a motor shaft (rotational shaft) of the transport motor 52, and outputs a pulse signal according to the rotation of the motor shaft.

  The buffer unit 57 is configured to store a slack portion of the web W between the conveyance roller 51 and the winding device 4. The buffer unit 57 includes support rollers 61 and 62 and a dancer roller 63.

  The support rollers 61 and 62 support the web W between the guide roller 45 and a take-in roller 66 of the winding device 4 described later. The support rollers 61 and 62 are spaced apart from each other in the left-right direction and arranged at the same height.

  The dancer roller 63 pushes down the web W by its own weight between the support rollers 61 and 62. Thereby, the slack of the web W between the conveyance roller 51 and the winding device 4 is absorbed by the buffer unit 57. The dancer roller 63 moves up and down due to the fluctuation of the amount of slack of the web W between the transport roller 51 and the winding device 4.

  The dancer roller position sensor 58 detects the vertical position (height position) of the dancer roller 63 of the buffer unit 57.

  The printing units 32A and 32B print the images on the front and back surfaces of the web W, respectively. The printing unit 32 </ b> A is disposed in the vicinity of the upper side of the web W between the guide rollers 39 and 40. The printing unit 32 </ b> B is disposed in the vicinity of the upper side of the web W between the guide rollers 41 and 42. The printing units 32A and 32B each include five head units 64.

  The head unit 64 has an ink jet head (not shown) and ejects ink onto the web W from the nozzles of the ink jet head to print an image. In each of the printing units 32A and 32B, the five head units 64 eject ink of different colors.

  The printing apparatus control unit 33 controls the operation of each unit of the printing apparatus 3. The printing apparatus control unit 33 includes a PLC (Programmable Logic Controller) or the like, and includes a CPU, a memory, and the like.

  When printing is performed, the printing apparatus control unit 33 causes the conveyance unit 31 to convey the web W, and discharges ink from the head units 64 of the printing units 32A and 32B to print an image on the web W. In addition, the printing apparatus control unit 33 counts the number of pulses of the encoder pulse signal output from the encoder 56, generates a pulse signal logically inverted at each specified count value Tk, as a transport speed pulse signal, Output to the winding device 4. The transport speed pulse signal indicates the transport speed of the web W by the transport roller 51, and is used to operate the winding device 4 in synchronization with the printing device 3. Details of the transport speed pulse signal will be described later.

  The winding device 4 rolls up the printed web W conveyed from the printing device 3 while conveying it. The winding device 4 is disposed on the downstream side (right side) of the printing device 3 in the transport direction of the web W. The take-up device 4 includes a pair of take-in rollers 66, a buffer unit 67, a brake roller 68, a brake unit 69, a take-up shaft 70, a take-up motor 71, a take-up motor 72, and a motor driver 73. , 74, a brake driver 75, speed reducers 76 to 78, and a take-up device control unit 79.

  The pair of take-in rollers 66 conveys the web W sent from the printing device 3 toward the take-up shaft 70 while taking in the take-up device 4. One take-in roller 66 of the pair of take-in rollers 66 is rotationally driven by a take-up motor 72, and the other take-in roller 66 is driven to rotate by one take-in roller 66. The pair of take-in rollers 66 is disposed at the upstream end (left end) of the winding device 4.

  The buffer portion 67 stores the slack portion of the web W between the intake roller 66 and the brake roller 68. The buffer unit 67 includes support rollers 81 and 82 and a dancer roller 83.

  The support rollers 81 and 82 support the web W between the intake roller 66 and the brake roller 68. The support rollers 81 and 82 are spaced apart from each other in the left-right direction and arranged at the same height.

  The dancer roller 83 pushes down the web W by its own weight between the support rollers 81 and 82. Thereby, the slack of the web W between the take-in roller 66 and the brake roller 68 is absorbed by the buffer portion 67. The dancer roller 83 moves up and down due to the fluctuation of the amount of slack of the web W between the intake roller 66 and the brake roller 68.

  The brake roller 68 is for applying a brake to the web W wound around the winding shaft 70. The brake roller 68 is disposed near the downstream side of the support roller 82. The brake roller 68 is driven to rotate by the web W wound around the winding shaft 70.

  The brake unit 69 applies tension to the web W wound around the winding shaft 70 by applying a brake to the web W via the brake roller 68. This can prevent the occurrence of wrinkles and the like on the web W wound around the winding shaft 70.

  The winding shaft 70 winds and holds the web W.

  The pickup motor 71 rotationally drives one pickup roller 66 of the pair of pickup rollers 66.

  The winding motor 72 rotates the winding shaft 70 in the clockwise direction in FIG. The web W is wound around the winding shaft 70 by the rotation of the winding shaft 70.

  The motor drivers 73 and 74 drive the pickup motor 71 and the winding motor 72, respectively.

  The brake driver 75 drives the brake unit 69.

  The reduction gear 76 transmits the rotation of the motor shaft of the pickup motor 71 to one of the pickup rollers 66 at a predetermined reduction ratio. The reduction gear 77 transmits the rotation of the motor shaft of the winding motor 72 to the winding shaft 70 at a predetermined reduction ratio. The reduction gear 78 transmits the rotation of the brake roller 68 to the output shaft of the brake portion 69 at a predetermined reduction ratio.

  The winding device control unit 79 controls the operation of each unit of the winding device 4. The winding device control unit 79 includes a CPU, a memory, and the like. The take-up device control unit 79 operates the take-up device 4 in synchronization with the printing device 3 based on the conveyance speed pulse signal input from the printing device 3. Specifically, the take-up device control unit 79 controls the take-in motor 71 and the take-up motor 72 so as to take up and take up the web W at the transfer speed based on the transfer speed pulse signal input from the printing apparatus 3 Do.

  Next, the above-described transport speed pulse signal will be described.

  As described above, the transport speed pulse signal is output from the printing device 3 to the winding device 4 as transport speed information indicating the transport speed of the web W by the transport roller 51.

  The transport speed pulse signal is output from the printing device 3 to the take-up device 4 as a pulse signal of a predetermined resolution Rt that has been predetermined.

  In the present embodiment, the defined resolution Rt is 6 LPI (Line Per Inch). Here, the resolution of the pulse signal indicates the number of pulses per inch. That is, the transport speed pulse signal is generated as a pulse signal of 6 pulses per inch (1/6 inch pulse signal).

  In the present embodiment, the printing apparatus control unit 33 counts the number of pulses of the encoder pulse signal output from the encoder 56, and generates a pulse signal logically inverted at each specified count value Tk as a transport speed pulse signal. Do.

  In the printing apparatus 3, the motor shaft one-rotation pulse number Pm and the specified count value Tk are set such that the conveyance speed pulse signal generated in this manner becomes a 1/6 inch pulse signal. The motor shaft one rotation pulse number Pm is the pulse number of the encoder pulse signal output by the encoder 56 for one rotation of the motor shaft of the transport motor 52.

  The combination of the motor shaft one-rotation pulse number Pm and the specified count value Tk is determined, for example, as follows.

  First, a basic pulse value Po [P / r], which is the number of pulses of a 1/6 inch pulse signal corresponding to one rotation of the motor shaft of the transport motor 52, is calculated. The basic pulse value Po is calculated by the following equation (1).

Po = Rt × φ × π / (25.4 × G) (1)
Here, φ [mm] is a diameter (conveyance roller diameter) of the conveyance roller 51 driven by the conveyance motor 52. G is a reduction gear ratio of the reduction gear 55.

  For example, if φ = 60 mm and G = 1.6, and Rt = 6 LPI as described above, then Po = 27.8 P / r.

  Next, first, with the toggle count value T = 1, the calculated value Pmc [P / r] of the number of pulses for one motor shaft revolution of the encoder pulse signal in that case is calculated.

  Here, as shown in FIG. 3, the toggle count value T is a count value of an encoder pulse signal for determining the timing of performing logic inversion when generating a 1/6 inch pulse signal as a transport speed pulse signal. is there.

  As shown in FIG. 3, one cycle of the 1⁄6 inch pulse signal corresponds to the time required to count twice the toggle count value T. For this reason, the number of pulses obtained by multiplying the basic pulse value Po by twice the toggle count value T is calculated as a calculated value Pmc of the number of pulses for one rotation of the motor shaft, as shown in the following equation (2).

Pmc = Po × (2 × T) (2)
Here, the encoder pulse signal used to generate the transport velocity pulse signal is the A-phase signal or the B-phase signal of the encoder 56, and FIG. 3 shows the A-phase signal. Further, the top stage of FIG. 3 shows a Z-phase signal of the encoder 56 indicating one rotation of the motor shaft.

  For example, in the case where the basic pulse value Po = 27.8 P / r as described above, the calculated value Pmc = 55.66 P / r of the number of pulses for one rotation of the motor shaft when the toggle count value T = 1. Become.

  Next, an integer value obtained by rounding off the calculated value Pmc of the number of pulses for one motor shaft revolution of the encoder pulse signal is calculated as the value of the motor shaft one-rotation pulse count Pm of the encoder pulse signal. For example, in the case where the calculated value Pmc = 55.66 P / r of the pulse number for one rotation of the motor shaft as described above, the pulse number for one motor shaft rotation Pm = 56 P / r.

  Next, when the toggle count value T = 1 and the number of pulses for one motor shaft rotation of the encoder pulse signal is the calculated motor shaft one rotation pulse number Pm, the transport speed pulse signal (1/6 inch pulse) The resolution Rc [LPI] of the pulse signal generated as a signal) is calculated. The resolution Rc is calculated by the following equation (3).

Rc = 25.4 × G × Pm / (φ × π × (2 × T)) (3)
For example, when φ = 60 mm and G = 1.6 as described above, Rc = 6.037 LPI when toggle count value T = 1 and motor shaft rotation pulse count Pm = 56 P / r.

  Next, an error E [%] of the calculated resolution Rc with respect to the defined resolution Rt is calculated. The error E is calculated by the following equation (4).

E = (| Rc−Rt | / Rt) × 100 (4)
For example, as described above, in the case of Rc = 6.037 LPI, the error E = 0.6142%.

  Then, when the error E is equal to or less than a preset threshold Et, it is determined as a pass, and when the error E is larger than the threshold Et, it is determined as a fail.

  For example, in the case where the threshold Et = 0.001%, if the error E = 0.6142% as described above, it is determined as a failure. That is, in the case of Rt = 6 LPI, φ = 60 mm, G = 1.6 as described above, the error E is a combination of the motor shaft one-rotation pulse number Pm = 56 P / r and the toggle count value T = 1. Since it is larger than the threshold Et, it fails.

  When the error E calculated as described above with the toggle count value T = 1 fails, 1 is added to the toggle count value T to make the toggle count value T = 2, and the above-described toggle count value T = 1 The error E is calculated similarly to the above. This is repeated until the toggle count value T for which the error E is determined to pass is found.

  When a toggle count value T for which the error E is determined to pass is found, the value of the toggle count value T is determined as a prescribed count value Tk. Further, the value of the motor shaft one rotation pulse number Pm calculated according to the toggle count value T is determined as the motor shaft one rotation pulse number Pm of the encoder 56. Thereby, a combination of the motor shaft one-rotation pulse number Pm and the specified count value Tk is determined.

  An example of calculation of the error E according to the toggle count value T in the case of Rt = 6 LPI, φ = 60 mm, and G = 1.6 described above is shown in FIG. In the example of FIG. 4, the threshold Et = 0.001%. In the example of FIG. 4, in the case of the toggle count value T = 38, the error E is equal to or less than the threshold Et with an error of 0.0004%, which is a pass. Therefore, it is determined that the prescribed count value Tk = 38. Further, the motor shaft one rotation pulse number Pm = 2115 when the toggle count value T = 38 is determined as the value of the motor shaft one rotation pulse number Pm of the encoder 56.

  The motor shaft one rotation pulse number Pm of the encoder 56 is set to a value determined as described above. When an encoder of a type capable of arbitrarily setting the value of the motor shaft one rotation pulse number Pm is used as the encoder 56, the motor shaft one rotation pulse number Pm is set to the value determined as described above. When using an encoder of a type in which the value of the motor shaft one rotation pulse number Pm is a fixed value as the encoder 56, the one designed for the motor shaft one rotation pulse number Pm to be the value determined as described above Used.

  Here, unlike the present embodiment, when the encoder pulse signal output from the encoder 56 is output as it is to the take-up device 4 as the transport speed pulse signal (1/6 inch pulse signal) as it is, one motor shaft rotation of the encoder 56 The number of pulses Pm is set to be an integer value obtained by rounding off the basic pulse value Po described above.

  In this case, the resolution of the transport speed pulse signal (1/6 inch pulse signal) which is an encoder pulse signal corresponds to the resolution Rc in the case of the toggle count value T = 1 described above. Therefore, the resolution of the transport speed pulse signal (1/6 inch pulse signal), which is an encoder pulse signal in the case of Rt = 6 LPI, φ = 60 mm, G = 1.6, is the same as the example described above. It becomes 6.037 LPI similarly to the value of resolution Rc in the upper stage. The error between this resolution and the specified resolution Rt is 0.6142%, which is larger than the threshold Et. Therefore, in this case, the transmission accuracy of the transport speed to the winding device 4 is lower than that in the present embodiment.

  Next, the operation of the printing system 1 will be described.

  When printing is performed by the printing system 1, the unwinding device control unit 21 drives the unwinding motor 15 and the delivery motor 16, and the printing device control unit 33 drives the transport motor 52 and the brake unit 49, and the winding device control unit Reference numeral 79 drives the take-in motor 71, the take-up motor 72, and the brake unit 69 to convey the web W.

  The printing apparatus control unit 33 controls the printing units 32A and 32B to print an image on the web W conveyed. When the printing of the image is completed, the unwinding device control unit 21, the printing device control unit 33, and the winding device control unit 79 end the transport of the web W.

  Here, at the time of printing, the printing apparatus control unit 33 drives and controls the conveyance motor 52 via the motor driver 53 based on the conveyance speed of the web W calculated from the encoder pulse signal output by the encoder 56 to carry The conveyance speed of the web W by the roller 51 is maintained at a predetermined printing conveyance speed.

  The printing apparatus control unit 33 also generates a conveyance speed pulse signal based on the encoder pulse signal output by the encoder 56 when the web W is conveyed, and outputs the conveyance speed pulse signal to the winding device 4.

  Specifically, the printing apparatus control unit 33 counts the number of pulses of the encoder pulse signal output from the encoder 56, and logically inverts the pulse signal that is logically inverted at each specified count value Tk set as the toggle count value T. , As a transport speed pulse signal. Then, the printing device control unit 33 outputs the conveyance speed pulse signal to the winding device 4.

  Since the motor shaft one-rotation pulse number Pm and the specified count value Tk are set as described above, the transport speed pulse signal generated by the printing apparatus control unit 33 has an error E with respect to the specified resolution Rt of the resolution Rc as the threshold Et. It is the following.

  The take-up device control unit 79 controls the take-in motor 71 and the take-up motor 72 so as to take up the web W while conveying the web W at the conveyance speed based on the conveyance speed pulse signal input from the printing apparatus control unit 33. As a result, control is performed so that no difference in conveyance speed occurs between the conveyance roller 51 and the winding device 4.

  Here, even if the take-up device control unit 79 performs the conveyance speed control based on the conveyance speed pulse signal as described above, the manufacturing error of the diameter of the conveyance roller 51, the slip between the conveyance roller 51 and the web W, etc. A conveyance speed difference may occur between the conveyance roller 51 and the winding device 4.

  In order to suppress the difference in conveyance speed between the conveyance roller 51 and the winding device 4 as described above, the printing apparatus control unit 33 performs adjustment processing of the conveyance speed pulse signal.

  The adjustment process of the transport speed pulse signal will be described with reference to the flowchart of FIG. The process of the flowchart of FIG. 5 is started when the transport of the web W is started.

  In step S1 of FIG. 5, the printing apparatus control unit 33 determines whether the dancer roller 63 of the buffer unit 57 is raised based on the output signal of the dancer roller position sensor 58.

  Here, when the conveyance speed of the web W by the winding device 4 is faster than the conveyance speed of the web W by the conveyance roller 51, the amount of slack of the web W between the conveyance roller 51 and the winding device 4 decreases, and the dancer roller 63 rises. That is, when the transport speed of the web W by the winding device 4 is faster than the transport speed of the web W by the transport roller 51, the accumulation amount of the web W in the buffer unit 57 decreases.

  If it is determined that the dancer roller 63 is moving up (step S1: YES), the printing apparatus control unit 33 increases the toggle count value T by a predetermined number (for example, 1) in step S2.

  For example, when the conveyance speed pulse signal is generated with the specified count value Tk as the toggle count value T, when the rise of the dancer roller 63 is detected, the printing apparatus control unit 33 sets the toggle count value T to (Tk + 1). Change to When the toggle count value T is changed from the specified count value Tk to (Tk + 1), as shown in FIG. 6, the pulse width of the generated transport velocity pulse signal and the interval between pulses increase. Thereby, the conveyance speed of the web W in the winding device 4 is reduced. As a result, the conveyance speed difference between the conveyance roller 51 and the winding device 4 is reduced.

  Returning to FIG. 5, after step S2, the printing apparatus control unit 33 proceeds to the process of step S5 described later.

  When it is determined in step S1 that the dancer roller 63 has not moved up (step S1: NO), in step S3, the printing apparatus control unit 33 determines whether the dancer roller 63 is lowered based on the output signal of the dancer roller position sensor 58. Decide whether or not.

  Here, when the conveyance speed of the web W by the winding device 4 is slower than the conveyance speed of the web W by the conveyance roller 51, the amount of slack of the web W between the conveyance roller 51 and the winding device 4 increases, and the dancer roller 63 falls. That is, when the transport speed of the web W by the winding device 4 is slower than the transport speed of the web W by the transport roller 51, the amount of the web W stored in the buffer unit 57 increases.

  If it is determined that the dancer roller 63 has not been lowered (step S3: NO), the printing apparatus control unit 33 proceeds to the process of step S5 described later.

  If it is determined that the dancer roller 63 is lowered (step S3: YES), the printing apparatus control unit 33 decreases the toggle count value T by a predetermined number (for example, 1) in step S4.

  For example, when the lowering of the dancer roller 63 is detected when the conveyance speed pulse signal is generated with the specified count value Tk as the toggle count value T, the printing apparatus control unit 33 sets the toggle count value T to (Tk− Change to 1). When the toggle count value T is changed from the specified count value Tk to (Tk-1), as shown in FIG. 6, the pulse width of the generated transport velocity pulse signal and the interval between pulses decrease. Thereby, the conveyance speed of the web W in the winding device 4 is increased. As a result, the conveyance speed difference between the conveyance roller 51 and the winding device 4 is reduced.

  Referring back to FIG. 5, after step S4, the printing apparatus control unit 33 proceeds to the process of step S5.

  In step S5, the printing apparatus control unit 33 determines whether the transport of the web W is completed. When it is determined that the transport of the web W is not completed (step S5: NO), the printing apparatus control unit 33 returns to step S1. If it is determined that the transport of the web W has ended (step S5: YES), the printing apparatus control unit 33 ends a series of processing.

  As described above, in the printing apparatus 3, the printing apparatus control unit 33 counts the number of pulses of the encoder pulse signal output from the encoder 56, and conveys the pulse signal logically inverted at each specified count value Tk. It generates as a velocity pulse signal. Further, in the printing apparatus 3, the motor shaft one rotation pulse number Pm and the specified count value Tk are set such that the error E with respect to the specified resolution Rt of the resolution Rc of the transport speed pulse signal becomes equal to or less than the threshold Et.

  As a result, the resolution Rc of the transport velocity pulse signal can be made closer to the specified resolution Rt, as compared with the case where the encoder pulse signal is used as the transport velocity pulse signal as it is. In addition, since it is not necessary to calculate to generate the transport speed pulse signal from the encoder pulse signal, the transfer of the transport speed of the web W to the winding device 4 is not delayed. Therefore, according to the printing device 3, the transmission accuracy of the transport speed of the web W to the winding device 4 can be improved.

  Further, in the printing apparatus 3, the printing apparatus control unit 33 adjusts the toggle count value T to be increased when the dancer roller 63 of the buffer unit 57 is raised. The printing apparatus control unit 33 also adjusts the toggle count value T to decrease when the dancer roller 63 is lowered. As a result, when a conveyance speed difference occurs between the conveyance roller 51 and the winding device 4, the pulse width of the conveyance speed pulse signal and the interval between the pulses can be adjusted to reduce the conveyance speed difference.

  In the embodiment described above, the configuration in which the encoder 56 used to generate the transport speed pulse signal is installed on the motor shaft of the transport motor 52 has been described, but the encoder used to generate the transport speed pulse signal is the transport roller 51 It may be installed on the rotary shaft of

  Further, the buffer unit 67 of the printing apparatus 3 and the adjustment process of the transport speed pulse signal may be omitted.

  Further, in the above-described embodiment, the configuration has been described in which the web W, which is the object to be transported, is transported toward the winding device 4, which is the downstream device, by rotational driving of the transport roller 51 of the printing device 3. However, the transported object is not limited to the web, and the downstream device is not limited to the winding device 4. The present invention is widely applicable to a transport apparatus that transports a transported object toward a downstream device by rotational driving of a rotating body and transmits the transport speed of the transported object to a downstream device.

  The present invention is not limited to the above embodiment as it is, and in the implementation stage, the constituent elements can be modified and embodied without departing from the scope of the invention. In addition, various inventions can be formed by appropriate combinations of a plurality of components disclosed in the above-described embodiment. For example, some components may be deleted from all the components shown in the embodiment.

[Supplementary note]
The present application discloses the following invention.

(Supplementary Note 1)
A transport mechanism that transports the transported object toward the downstream device by rotational driving of the rotating body;
An encoder that outputs an encoder pulse signal according to rotation of a rotating shaft that rotates when the rotating body is driven to rotate;
The number of pulses of the encoder pulse signal is counted, and a pulse signal logically inverted at a specified count value is generated as a conveyance speed pulse signal indicating the conveyance speed of the object by the conveyance mechanism, and the generated conveyance A controller for outputting a velocity pulse signal to the downstream device;
The conveyance is characterized in that the number of output pulses of the encoder for one rotation of the rotation shaft and the prescribed count value are set such that an error with respect to the prescribed resolution of the resolution of the transport speed pulse signal is equal to or less than a threshold. apparatus.

(Supplementary Note 2)
The transported object transported by the transport mechanism is a web,
The downstream apparatus transports the web transported by the transport mechanism at a transport speed based on the transport speed pulse signal,
The apparatus further comprises a reservoir for storing a slack portion of the web between the transport mechanism and the downstream device;
The control unit
When the accumulation amount of the web in the accumulation portion is decreased, the count value of the number of pulses of the encoder pulse signal is increased to determine the timing of logic inversion at the time of generation of the conveyance speed pulse signal;
When the accumulation amount of the web in the accumulation portion is increased, it is adjusted to decrease the count value of the pulse number of the encoder pulse signal to determine the timing of logic inversion at the time of generation of the conveyance speed pulse signal. The transport apparatus according to claim 1, characterized by.

DESCRIPTION OF SYMBOLS 1 printing system 2 unwinding apparatus 3 printing apparatus 4 winding apparatus 31 conveyance part 32A, 32B printing part 33 printing apparatus control part 51 conveyance roller 52 conveyance motor 56 encoder 57 buffer part 58 dancer roller position sensor 63 dancer roller 66 intake roller 70 winding Take-up shaft 71 Take-up motor 72 Take-up motor 79 Take-up device control unit

Claims (2)

A transport mechanism that transports the transported object toward the downstream device by rotational driving of the rotating body;
An encoder that outputs an encoder pulse signal according to rotation of a rotating shaft that rotates when the rotating body is driven to rotate;
The number of pulses of the encoder pulse signal is counted, and a pulse signal logically inverted at a specified count value is generated as a conveyance speed pulse signal indicating the conveyance speed of the object by the conveyance mechanism, and the generated conveyance A controller for outputting a velocity pulse signal to the downstream device;
The conveyance is characterized in that the number of output pulses of the encoder for one rotation of the rotation shaft and the prescribed count value are set such that an error with respect to the prescribed resolution of the resolution of the transport speed pulse signal is equal to or less than a threshold. apparatus. The transported object transported by the transport mechanism is a web,
The downstream apparatus transports the web transported by the transport mechanism at a transport speed based on the transport speed pulse signal,
The apparatus further comprises a reservoir for storing a slack portion of the web between the transport mechanism and the downstream device;
The control unit
When the accumulation amount of the web in the accumulation portion is decreased, the count value of the number of pulses of the encoder pulse signal is increased to determine the timing of logic inversion at the time of generation of the conveyance speed pulse signal;
When the accumulation amount of the web in the accumulation portion is increased, it is adjusted to decrease the count value of the pulse number of the encoder pulse signal to determine the timing of logic inversion at the time of generation of the conveyance speed pulse signal. The transport apparatus according to claim 1, characterized in that: