Printing device and adhesion method for adhering recording medium to conveyance surface

Abstract

A printing apparatus (1) comprises: a conveyance member (211) that has a conveyance surface (211a) and moves the conveyance surface (211a) along a conveyance direction of a recording medium W; a pressing member (224) that is positioned opposite to the conveyance surface (211a) of the conveyance member (211) and is capable of pressing the recording medium (W) against the conveyance surface (211a); a first drive unit (M1) that drives the conveyance member (211) so that the conveyance surface (211a) of the conveyance member (211) can move along the conveyance direction of the recording medium (W); a second drive unit (M2) that is capable of moving the pressing member (224) along the conveyance direction; and a control unit that controls operations of the first drive unit (M1) and the second drive unit (M2). The control unit is capable of performing a first movement process in which the second drive unit (M2) moves the pressing member (224) to the upstream side in the conveyance direction, from a state in which the pressing member (224) presses the recording medium (W) against the conveyance surface (211a) at a prescribed position (P2) in the conveyance direction.

Description

Printing apparatus and adhesion method for adhering recording medium to conveyance surface

[0001] The present disclosure relates to a printing apparatus and an adhesion method for adhering a recording medium to a conveyance surface.

[0002] Patent Document 1 discloses application of an inkjet-type printing apparatus to textile printing. The printing apparatus includes an endless conveyance belt serving as a conveyance member for conveying a print medium such as a cloth member, an ink head for ejecting ink from above onto the recording medium on the conveyance belt, and a carriage that drives the ink head in a main scanning direction. The conveyance belt has, on an outer peripheral surface thereof, an adhesive conveyance surface capable of holding the recording medium. The printing apparatus includes, in a conveyance direction of the recording medium, a supply roller located upstream of the conveyance belt, and a pressing roller located upstream of the ink head and facing the conveyance surface of the conveyance belt. When the recording medium is supplied to the conveyance surface by the supply roller, the recording medium is sandwiched between the pressing roller and the conveyance surface and adhered (one example of adhesion) to the conveyance surface. The recording medium adhered to the conveyance surface is intermittently supplied to a printing position facing the ink head by the conveyance belt.

[0003] Japanese Patent Application Laid-Open No. 2002-249267

[0004] A printing apparatus according to one aspect of the present disclosure includes: a conveyance member having a conveyance surface to which a recording medium can be adhered, the conveyance member conveying the recording medium by moving the conveyance surface along a predetermined conveyance direction; a pressing member positioned opposite to the conveyance surface of the conveyance member and capable of pressing the recording medium against the conveyance surface; a first driving section that drives the conveyance member such that the conveyance surface of the conveyance member is movable along the conveyance direction; a second driving section capable of moving the pressing member along the conveyance direction; and a control section that controls operations of the first driving section and the second driving section. The control section is capable of executing a first movement process in which, from a state where the pressing member presses the recording medium against the conveyance surface at a predetermined position in the conveyance direction, the second driving section moves the pressing member to an upstream side in the conveyance direction.

[0005] A method for attaching a recording medium to a printing apparatus comprising a transport member having a transport surface to which a recording medium can be attached, and transporting the recording medium by moving the transport surface along a predetermined transport direction, and a pressing member positioned opposite the transport surface of the transport member and capable of pressing the recording medium against the transport surface, the method for attaching the recording medium to the transport surface includes a first step of moving the pressing member upstream in the transport direction from a state in which the recording medium is pressed against the transport surface by the pressing member at a predetermined position in the transport direction.

[0006] Figure 1 is a schematic side view showing the overall configuration of a printing apparatus according to Embodiment 1 of the present disclosure. Figure 2 is an enlarged view showing the supply-side transport section in an enlarged view. Figure 3 is a block diagram of the printing apparatus according to this embodiment. Figure 4 is a time chart showing an example of control of the printing apparatus by the control unit. Figure 5 is a diagram schematically showing the tension state acting on the workpiece W during belt feeding in a printing apparatus according to a comparative example. Figure 6A is a diagram schematically showing the tension state acting on the workpiece W during belt stopping. Figure 6B is a diagram schematically showing the tension state acting on the transport belt while the pressing roller is moved from the first position to the second position by forward movement processing. Figure 7 is a diagram corresponding to Figure 2 showing Embodiment 2.

[0007] The printing apparatus 1 according to the present disclosure will be described below with reference to the drawings.

[0008] (Embodiment 1) Figure 1 is a schematic side view showing the overall configuration of a printing apparatus 1 according to Embodiment 1 of the present disclosure. In the following description, the X, Y, and Z directions are defined as mutually orthogonal, as shown in Figure 1. The Z direction is the vertical direction, the X and Y directions are mutually orthogonal directions on the horizontal plane, the X direction is the direction extending perpendicular to the plane of the paper in Figure 1, and the Y direction is the direction extending left to right in Figure 1. These directions are defined for convenience to make the description of the printing apparatus 1 easier to understand and do not limit the technical scope of the present disclosure in any way.

[0009] [Printing device 1] Printing device 1 prints an image onto a long workpiece W (recording medium) using an inkjet method. In this example, the workpiece W consists of a recording medium such as a woven or knitted fabric made of a stretchable material. However, the workpiece W does not necessarily have to be a recording medium made of a stretchable material. Furthermore, the workpiece W is not limited to woven or knitted fabrics, but may also be a recording medium such as a paper sheet or a resin sheet.

[0010] On both sides of the printing device 1 in the Y direction, a recording medium supply device 100 and a winding device 40 are located, and the workpiece W is transported straddling the printing device 1, the recording medium supply device 100, and the winding device 40. The printing device 1 performs the printing process on the workpiece W supplied from the recording medium supply device 100, and after printing, the workpiece W is wound up by the winding device 40.

[0011] The printing apparatus 1 comprises a frame 10, a main transport unit 20, and a printing unit 30. The frame 10 is a framework member for mounting various components of the printing apparatus 1. The main transport unit 20 intermittently transports the workpiece W from the upstream side to the downstream side in the transport direction within the printing area A where inkjet printing is performed. Here, the transport direction of the workpiece W is the direction along the transport path of the workpiece W, and as shown by the arrows in Figure 1, it changes in various directions depending on the position of the workpiece W. In the example in Figure 1, for example, the transport direction of the workpiece W in the printing unit 30 is the Y direction (left-right direction in Figure 1).

[0012] The printing unit 30 includes a carriage 31 configured to reciprocate in the main scanning direction, and a plurality of ink heads 32 mounted on the carriage 31, each ejecting ink of a different color. During the inkjet printing process, the printing unit 30 performs the printing process on the workpiece W by reciprocating the carriage 31 in the main scanning direction (in this example, the X direction) perpendicular to the transport direction of the workpiece W, while ejecting ink from each ink head 32.

[0013] In this example, the multiple ink heads 32 include six upstream ink heads 32A and six downstream ink heads 32B corresponding to six colors, for example, orange, green, yellow, red, blue, and black. The six upstream ink heads 32A and the six downstream ink heads 32B are arranged in a staggered pattern, spaced apart in the main scanning direction (X direction) and overlapping in the sub-scanning direction (Y direction in this example). Each ink head 32 has an ejection port for ejecting droplets of the target liquid using an ejection method such as a piezoelectric method using a piezoelectric element or a thermal method using a heating element. Note that the number and arrangement of the ink heads 32 are not limited to this.

[0014] The frame 10 has a structure that combines a metal frame member and a sheet metal member.

[0015] The main transport unit 20 includes a printing area transport unit 21 located adjacent to the printing area A, a supply-side transport unit 22 that supplies workpieces W to the upstream end of the printing area transport unit 21, and a discharge-side transport unit 23 that receives workpieces W discharged from the downstream end of the printing area transport unit 21 and transports them further downstream.

[0016] The printing area transport unit 21 includes a transport belt 211 (an example of a transport member), a drive roller 213, a driven roller 212, an upstream support roller 215, and a downstream support roller 216.

[0017] The conveyor belt 211 is wound around the drive roller 213 and the driven roller 212, allowing it to circulate in the front-rear direction. The outer surface of the conveyor belt 211 is an adhesive surface capable of holding the workpiece W by adhesion. The conveyor belt 211 has a conveying surface 211a for conveying the workpiece W. The conveying surface 211a is the surface of the outer surface of the conveyor belt 211 that faces the ink head 32 (i.e., the upper surface of the conveyor belt 211). The workpiece W is held by adhesion (an example of attachment) to the conveying surface 211a. As the conveyor belt 211 circulates in the clockwise direction in Figure 1, the conveying surface 211a moves from the left side to the right side in Figure 1 along the Y direction. This movement of the conveying surface 211a conveys the workpiece W from the recording medium supply device 100 to the printing area A directly below the printing unit 30.

[0018] The drive roller 213 and the driven roller 212 extend in the main scanning direction (X direction) and are positioned at a distance from each other in the workpiece W transport direction (Y direction). Both ends of the drive roller 213 and the driven roller 212 are rotatably supported by the frame 10.

[0019] The drive roller 213 is driven by the first motor M1 (an example of the first drive unit) to make it rotate around the conveyor belt 211. When the printing process is performed in the printing unit 30, the drive roller 213 generates a conveying force that intermittently feeds the workpiece W in the printing unit 30. The driven roller 212 rotates in conjunction with the rotation of the conveyor belt 211, while applying tension to the conveyor belt 211 to prevent slack.

[0020] The supply-side transport unit 22 guides the workpiece W supplied from the recording medium supply device 100 to the transport surface 211a, and can hold the workpiece W to the transport surface 211a by adhesion.

[0021] Figure 2 is an enlarged view showing the supply-side conveying section 22. The supply-side conveying section 22 includes a widening roller 221, a first guide roller 222, a second guide roller 223 (an example of a guide member), and a pressing roller 224. Each roller 221 to 224 rotates in accordance with the feeding movement of the workpiece W. The workpiece W is wound around the widening roller 221, the first guide roller 222, and the second guide roller 223 in the order from the upstream side to the downstream side in the conveying direction. The workpiece W then passes between the pressing roller 224 and the conveying surface 211a downstream of the second guide roller 223 in the conveying direction. As a result, the workpiece W is pressed against the conveying surface 211a of the conveying belt 211 by the pressing roller 224 and adheres to it.

[0022] The widening roller 221 can suppress the occurrence of wrinkles and other defects by correcting sagging in the width direction (X direction) of the workpiece W. The widening roller 221 has a barrel shape in which both ends are narrower than the central part.

[0023] The first guide roller 222 and the second guide roller 223 are capable of guiding the workpiece W along the transport direction. The first guide roller 222 and the second guide roller 223 have fixed positions and change the orientation of the workpiece W during transport.

[0024] The first guide roller 222 is located at the same height as the widening roller 221. In the Y direction, the first guide roller 222 is spaced further away from the widening roller 221 on the side closer to the printing section 30 (right side in Figure 2). The first guide roller 222 is rotatably supported at both ends by a pair of first sheet metal members 225. The pair of first sheet metal members 225 (only one is shown in Figure 2) are located at the upstream end of the frame 10 in the transport direction. The pair of first sheet metal members 225 are spaced apart in the X direction.

[0025] The second guide roller 223 is located below the first guide roller 222. In the Y direction, the second guide roller 223 is located further from the printing section 30 than the press roller 224, which will be described later (left side in Figure 2). The second guide roller 223 is located opposite the upstream end of the transport surface 211a. The axis of the second guide roller 223 is lower than the axis of the press roller 224. As will be described later, the second guide roller 223 is capable of reciprocating in the Y direction in conjunction with the reciprocating movement of the press roller 224 between the first position P1 and the second position P2 (corresponding to a predetermined position). When the press roller 224 is in the first position P1 (solid line in Figure 2), the axis of the second guide roller 223 is located further from the printing section 30 than the axis of the first guide roller 222 in the Y direction (left side in Figure 2).

[0026] The second guide roller 223, when viewed from the X direction (i.e., the width direction perpendicular to the transport direction), causes the workpiece W to enter the space between the press roller 224 and the transport surface 211a at an angle from the upstream side in the transport direction. At this time, the entry angle of the workpiece W wrapped around the second guide roller 223 with respect to the transport surface 211a (the angle between the workpiece W and the transport surface 211a) may be, for example, 5° to 30° or 10° to 20°. On the other hand, when the press roller 224 is in the second position P2 (the state shown by the dashed line in Figure 2), the axis position of the second guide roller 223 is located closer to the printing section 30 in the Y direction than the axis position of the first guide roller 222 (the right side in Figure 2). At this time, the entry angle of the workpiece W with respect to the transport surface 211a is the same as (or includes errors) as when the press roller 224 is in the first position P1. The smaller this entry angle, the more the workpiece W can be positioned as horizontally as possible between the second guide roller 223 and the pressing roller 224 (that is, the workpiece W can be brought closer to being parallel to the conveying surface 211a). This reduces the possibility of wrinkles or other damage occurring to the workpiece W during the retraction process of the pressing roller 224, which will be described later.

[0027] The second guide roller 223 is rotatably supported by a pair of second sheet metal members 226, separate from the pair of first sheet metal members 225. The pair of second sheet metal members 226 are located inward from the pair of first sheet metal members 225 in the X direction. The pair of second sheet metal members 226 are spaced apart in the X direction. The pair of second sheet metal members 226 are supported so as to be linearly movable in the Y direction by a linear guide mechanism 7 (shown only in Figure 2). The linear guide mechanism 7 has a rail member 71 extending in the Y direction and a slide table (not shown) that engages with the rail member 71 so as to be movable in the Y direction. The pair of second sheet metal members 226 are fixed to the slide table. Thus, the pair of second sheet metal members 226 are supported so as to be movable in the Y direction relative to the rail member 71. Note that the configuration of the linear guide mechanism 7 is not limited to this and may be any configuration.

[0028] The pressing roller 224 can press the workpiece W against the conveying surface 211a of the conveying belt 211 and make it adhere. The pressing function of the pressing roller 224 against the workpiece W is achieved by making the distance between the pressing roller 224 and the conveying surface 211a of the conveying belt 211 smaller than the thickness of the workpiece W. The pressing roller 224 may be in contact with the conveying surface 211a, and in this case, the pressing roller 224 may be constantly pressed against the conveying surface 211a by a biasing member such as a spring.

[0029] The press roller 224 is positioned opposite the upstream end of the workpiece transport direction on the transport surface 211a. The press roller 224 is located closer to the printing section 30 (right side in Figure 2) than the second guide roller 223 in the Y direction. The press roller 224 is rotatably supported by the second sheet metal member 226 together with the second guide roller 223.

[0030] The second sheet metal member 226 is driven to move in the Y direction by a second motor M2 (an example of a second drive unit; see Figure 1). The second motor M2 consists of, for example, a drive motor of a ball screw mechanism connected to the second sheet metal member 226. The second motor M2 can drive the press roller 224 and the second guide roller 223 in the Y direction via the second sheet metal member 226. The press roller 224 can reciprocate between a first position P1 and a second position P2 by being driven in the Y direction by the second motor M2. In other words, it can move in both directions: from the first position P1 to the second position P2 and from the second position P2 to the first position P1. Since both the press roller 224 and the second guide roller 223 are supported by a pair of second sheet metal members 226, the relative positional relationship between the two rollers is maintained constant when moving in the Y direction. Maintaining a constant relative positional relationship between the two rollers includes, for example, maintaining a constant upstream-downstream positional relationship between the pressing roller 224 and the second guide roller 223 in the conveying direction, maintaining a constant separation distance between the two rollers in the Y-direction and the vertical direction, and maintaining a constant distance from the conveying surface 211a.

[0031] Returning to Figure 1, the discharge-side conveying section 23 has a tension roller 231. Both ends of the tension roller 231 are rotatably supported by a pair of left and right sheet metal members 232 (only one is shown in Figure 1) located at the downstream end of the frame 10 in the conveying direction. The workpiece W is conveyed downstream by passing over this tension roller 231. A winding device 40 for workpiece recovery is provided downstream of the tension roller 231, and the workpiece W discharged downstream by the discharge-side conveying section 23 is wound into a roll and recovered by the winding device 40.

[0032] [Recording medium supply device 100] The recording medium supply device 100 feeds the rolled workpiece W toward the printing device 1. The recording medium supply device 100 includes a feed roller 101, a positioning roller 102, a first tension roller 103, a second tension roller 104, a third tension roller 105, a fourth tension roller 106, and a support frame 110 that rotatably supports these rollers 101 to 106.

[0033] The feed roller 101 can pass through the axial center of the rolled workpiece W and feed the workpiece W downstream.

[0034] The positioning roller 102 can prevent misalignment of the workpiece W, which has been fed out by the feed roller 101, in the transport width direction (X direction).

[0035] The first tension rollers 103 to the fourth tension rollers 106 are capable of applying tension to the workpiece W. Of these four rollers, the first tension roller 103 and the third tension roller 105 are dancer rollers supported on the support frame 110 so as to be movable in the vertical direction. The dancer rollers are capable of moving up and down in conjunction with the movement of the workpiece W in the transport direction, and apply tension to the workpiece W by their own weight.

[0036] The workpiece W is wound in the order of the first tension roller 103, positioning roller 102, second tension roller 104, third tension roller 105, and fourth tension roller 106, from the upstream side to the downstream side in the transport direction. The workpiece W that is sent downstream of the fourth tension roller 106 is supplied to the supply-side transport section 22 of the printing device 1.

[0037] [Control System Configuration] Figure 3 is a block diagram of the printing apparatus 1 according to this embodiment. The printing apparatus 1 further comprises a control unit 90 that comprehensively controls the operation of each part of the printing apparatus 1, a carriage drive unit 3S, an I / F 91, and an image memory 92. The control unit 90 includes a CPU (Central Processing Unit), a ROM (Read Only Memory) for storing control programs, a RAM (Random Access Memory) used as a working area for the CPU, etc. In addition to the first motor M1 and second motor M2 and the ink head 32 mentioned above, the control unit 90 is electrically connected to the carriage drive unit 3S, the I / F 91, the image memory 92, etc. The carriage drive unit 3S includes a motor (not shown) that rotates a timing belt 16 to move the carriage 31 back and forth along the main scanning direction.

[0038] The image memory 92 temporarily stores print image data provided by an external device, such as a personal computer.

[0039] The I / F91 is an interface circuit for enabling data communication with external devices. For example, it creates communication signals according to the communication protocol of a network connecting the printing device 1 and external devices, and converts the communication signals from the network into data in a format that the printing device 1 can process. Print instruction signals transmitted from a personal computer or the like are provided to the control unit 90 via the I / F91, and image data is stored in the image memory 92 via the I / F91.

[0040] The control unit 90 functions by having the CPU execute a control program stored in the ROM, thereby comprising a drive control unit 901, a discharge control unit 902, and a storage unit 903.

[0041] The drive control unit 901 controls the conveying operation of the workpiece W by controlling the first motor M1. Further, the drive control unit 901 controls the reciprocating movement of the carriage 31 along the main scanning direction by controlling the carriage drive unit 3S. The drive control unit 901 further controls the movement operation of the pressing roller 224 and the second guide roller 223 along the Y direction by controlling the second motor M2.

[0042] The discharge control unit 902 inputs a predetermined command signal to the ink head 32 based on image data received from the I / F 91 or the image memory 92, and controls the discharge operation of ink of each color.

[0043] Note that the structure of the control unit 90 is not limited to the above embodiment, and may be in a different mode from the above depending on the structures of the apparatus and the program. In other words, it can be said that the control unit 90 executes each function of the aforementioned drive control unit 901, discharge control unit 902, and storage unit 903.

[0044] [Details of Print Control] Figure 4 is a time chart showing an example of the operation of the printing apparatus 1. The upper diagram in Figure 4 shows the temporal change of the moving speed of the carriage 31, the middle diagram in Figure 4 shows the conveying speed of the workpiece W by the conveying belt 211 (that is, the moving speed of the conveying surface 211a), and the lower diagram in Figure 4 shows the moving speed in the Y direction of the pressing roller 224 and the second guide roller 223.

[0045] First, a specific example of print control executed by the control unit 90 will be described with reference to the upper diagram and the middle diagram of the time chart in Figure 4. This print control is realized through the cooperation of the drive control unit 901 and the discharge control unit 902.

[0046] In the aforementioned print control, the drive control unit 901 alternately executes belt stop processing and belt feeding processing as shown in the middle diagram of Figure 4, thereby intermittently conveying the workpiece W from the upstream side to the downstream side in the conveying direction.

[0047] In the belt feeding process, the drive control unit 901 causes the first motor M1 (see FIG. 1) to rotate the drive roller 213 in the forward direction, thereby moving the conveyance surface 211a of the conveyance belt 211 from the upstream side to the downstream side in the conveyance direction by a predetermined distance (a distance corresponding to the image pitch in the length direction of the workpiece W).

[0048] In the belt stopping process, the feeding movement of the conveyance belt 211 is stopped for a predetermined period of time by maintaining the first motor M1 in a stopped state.

[0049] The drive control unit 901 controls the carriage drive unit 3S during execution of the belt stopping process to cause the carriage 31 to perform a forward path movement operation or a return path movement operation along the main scanning direction. The ejection control unit 902 causes the carriage 31 to perform an ejection operation of ink of each color while the carriage 31 is performing the forward path movement operation or the return path movement operation. Accordingly, in a state where the conveyance belt 211 is stopped, the carriage 31 scans in the main scanning direction while ejecting ink from the ink head 32, so that one pitch of image data is printed on the workpiece W. In the present embodiment, for convenience, movement from the near side to the deep side of the paper surface in the X direction in FIG. 1 is defined as forward path movement, but the present invention is not limited thereto, and the direction of forward path movement may be opposite to this.

[0050] The drive control unit 901 causes the carriage 31 to perform a preparation operation for the next movement operation in the main scanning direction every time the forward path movement operation or the return path movement operation of the carriage 31 in the main scanning direction during the belt stopping process is completed. The preparation operation is an operation for switching between the forward path movement operation and the return path movement operation of the carriage 31, and by this preparation operation, the carriage 31 moves to an initial position for the next movement operation. That is, when the immediately preceding movement operation of the carriage 31 is a forward path movement operation, the drive control unit 901 moves the carriage 31 to the initial position for the return path movement operation; whereas when the immediately preceding movement operation of the carriage 31 is a return path movement operation, the drive control unit 901 moves the carriage 31 to the initial position for the forward path movement operation.

[0051] The drive control unit 901 intermittently feeds the workpiece W by alternately repeating belt feeding and belt stopping processes, and prints image data on the workpiece W one pitch at a time by moving the carriage 31 in the main scanning direction each time the workpiece W is stopped.

[0052] [Workpiece W Attachment Control] Conventionally, when a recording medium is transported and moved by a conveyor belt (conveyor member), the tension acting on the recording medium increases, sometimes causing the recording medium to stretch in the transport direction. In this embodiment, to address this problem, the control unit 90 performs attachment control to attach the workpiece W to the transport surface 211a of the conveyor belt 211 in parallel with the printing control described above. A specific example of this attachment control will be described below with reference to Figures 2 and 4 (especially the lower figure).

[0053] In the aforementioned attachment control, as shown in the lower diagram of Figure 4, the drive control unit 901 alternately executes forward movement processing and backward movement processing of the pressing roller 224 and the second guide roller 223. In this example, as an example, movement from the first position P1 to the second position P2 is defined as "forward movement," and movement from the second position P2 to the first position P1 is defined as "backward movement." The drive control unit 901 executes the forward movement processing in synchronization with the execution of the belt feeding processing, and executes the backward movement processing during the belt stopping processing. As will be described in detail later, the attachment of the workpiece W to the conveying surface 211a of the conveying belt 211 is performed during this backward movement processing.

[0054] First, let's explain the forward movement process. In the forward movement process (see the lower diagram in Figure 4), when the drive control unit 901 performs the belt feeding process of the conveyor belt 211 (see the middle diagram in Figure 4), it controls the second motor M2 to move the press roller 224 and the second guide roller 223 forward from the upstream side to the downstream side in the conveying direction (moving from the left side to the right side in Figure 4) in synchronization with the feeding movement of the conveyor belt 211.

[0055] During the forward movement process, the press roller 224 moves forward from the first position P1 (see Figure 2) to the second position P2. The first position P1 is where the press roller 224 is offset slightly to the right of the first guide roller 222 in Figure 2. The second position P2 is where the press roller 224 is separated by a predetermined distance L in the Y direction from the first position P1, on the side closer to the printing section 30 (to the right in Figure 2). In other words, the second position P2 is downstream of the first position P1 in the workpiece transport direction.

[0056] In this example, during the forward movement process, the forward movement of the press roller 224 and the second guide roller 223 (see the lower part of Figure 4) is started simultaneously with the start of the feed movement of the conveyor belt 211 at time t1 (see the middle diagram of Figure 4). Note that "simultaneous" here does not necessarily mean exactly the same time, and may include a predetermined error. This also applies to the following explanation. Furthermore, in the following explanation, "predetermined error" means, for example, an error of ±10% or less, but is not limited to this.

[0057] Here, as shown in the middle diagram of Figure 4, the speed profile of the conveyor belt 211 during feed movement is trapezoidal (isosceles trapezoidal in this example). In other words, the feed movement of the conveyor belt 211 consists of accelerated movement, constant speed movement, and deceleration movement. Hereafter, the speed during this constant speed movement will be defined as the feed speed VB of the conveyor belt 211. The feed speed VB corresponds to the preset set movement speed of the conveyor belt 211.

[0058] In the forward movement process of this example, as shown in the lower diagram of Figure 4, the speed profiles of the press roller 224 and the second guide roller 223 during forward movement are similarly trapezoidal (isospherical trapezoidal in this example). In other words, the forward movement of the press roller 224 and the second guide roller 223 consists of acceleration, constant speed, and deceleration. Hereinafter, the speed during this constant speed movement will be defined as the forward movement speed VR1 of the press roller 224 and the second guide roller 223. The forward movement speed VR1 corresponds to a preset set movement speed during the forward movement of the press roller 224 and the second guide roller 223.

[0059] In this example, during the forward movement process, the feed rate VB of the conveyor belt 211 and the forward movement speed VR1 of the press roller 224 and the second guide roller 223 are equivalent (the same or include a predetermined error).

[0060] Furthermore, in the forward movement process in this example, the acceleration time ΔTB1 during the feed movement of the conveyor belt 211 (see the middle diagram in Figure 4) and the acceleration time ΔTR1 during the forward movement of the press roller 224 and the second guide roller 223 (see the lower diagram in Figure 4) are equivalent (the same or include a predetermined error). Therefore, the time t2 at which the acceleration state of the conveyor belt 211 ends and switches to a constant speed state is the same as the time at which the acceleration state of the press roller 224 and the second guide roller 223 ends and switches to a constant speed state.

[0061] Furthermore, the drive control unit 901 starts decelerating the press roller 224 and the second guide roller 223 at the same time t3 when the conveyor belt 211 starts to decelerate after reaching a constant speed state.

[0062] The deceleration time ΔTB2 during the feed movement of the conveyor belt 211 (see the middle diagram in Figure 4) and the deceleration time ΔTR2 during the forward movement of the press roller 224 and the second guide roller 223 (see the lower diagram in Figure 4) are equivalent (the same or include a predetermined error). Therefore, the time t4 at which the deceleration state of the conveyor belt 211 ends and switches to a stopped state is the same as the time at which the deceleration state of the press roller 224 and the second guide roller 223 ends and switches to a stopped state.

[0063] The absolute values ​​of the acceleration before reaching a constant speed state and the absolute values ​​of the deceleration (negative acceleration) after reaching a constant speed state during the forward movement of the press roller 224 and the second guide roller 223 are equal to the absolute values ​​of the acceleration before reaching a constant speed state (corresponding to the reference acceleration) and the absolute values ​​of the deceleration after reaching a constant speed state (corresponding to the reference deceleration) during the feed movement of the conveyor belt 211.

[0064] This can also be seen by referring to the speed profiles of the press roller 224 and the second guide roller 223 shown in Figure 4 (lower diagram of Figure 4) and the speed profile of the conveyor belt 211 during its feed movement (middle diagram of Figure 4), and noting that the slopes of the straight lines during acceleration and deceleration in both speed profiles are equivalent (the same or include a predetermined error).

[0065] Next, the backward movement process will be described. In the backward movement process (see the lower diagram in Figure 4), the drive control unit 901 controls the second motor M2 during the belt stopping process (see the middle diagram in Figure 4) to move the press roller 224 and the second guide roller 223 backward (from the right side to the left side in Figure 4). In the backward movement process, the press roller 224 moves from the second position P2 (see Figure 2) to the first position P1 while rolling on the upper surface of the workpiece W. As a result, the portion of the workpiece W corresponding to the distance L between the second position P2 and the first position P1 is pressed against the conveying surface 211a by the press roller 224 and adhered to it (attached).

[0066] In the backward movement process of this example (see the lower diagram of Figure 4), the speed profile of the press roller 224 and the second guide roller 223 during backward movement is triangular (isosceles triangle in this example). In other words, the backward movement of the press roller 224 and the second guide roller 223 consists of acceleration and deceleration. Hereafter, the speed at the end of this acceleration movement (in other words, the start of the deceleration movement) is defined as the backward movement speed VR2 of the press roller 224 and the second guide roller 223. The backward movement speed VR2 corresponds to a preset set movement speed during the backward movement of the press roller 224 and the second guide roller 223. Note that the speed profile is not limited to a triangular shape; it may also be trapezoidal.

[0067] In the backward movement process in this example, the backward movement speed VR2 is smaller than the feed speed VB of the conveyor belt 211 described above. The backward movement speed VR2 is, for example, 1 / 3 to 1 / 2 of the feed speed VB of the conveyor belt 211.

[0068] The absolute values ​​of the acceleration before reaching a constant speed state and the absolute values ​​of the deceleration (in other words, negative acceleration) after reaching a constant speed state during the backward movement of the press roller 224 and the second guide roller 223 are each smaller than the absolute values ​​of the acceleration before reaching a constant speed state (corresponding to the reference acceleration) and the absolute values ​​of the deceleration (a negative acceleration, corresponding to the reference deceleration) after reaching a constant speed state during the feed movement of the conveyor belt 211.

[0069] This can also be seen by referring to the speed profiles of the pressing roller 224 and the second guide roller 223 shown in Figure 4 (lower diagram of Figure 4) and the speed profile of the conveyor belt 211 during feeding movement (middle diagram of Figure 4), where the former has a gentler slope of the straight line during acceleration and deceleration compared to the latter.

[0070] In the backward movement process of this example, the drive control unit 901 starts the backward movement of the press roller 224 and the second guide roller 223 at the same time t4 when the belt feeding process of the conveyor belt 211 described above is completed. The timing of starting this backward movement may be later than time t4.

[0071] Furthermore, in the backward movement process of this example, the drive control unit 901 terminates the backward movement of the press roller 224 and the second guide roller 223 before the time t1 at which the belt feeding process of the conveyor belt 211 begins. The timing at which the backward movement of the press roller 224 and the second guide roller 223 is terminated may be simultaneous with the time t1 at which the belt feeding process of the conveyor belt 211 begins.

[0072] [Effects of Embodiment 1] As described above, in this embodiment, the control unit 90 can perform a backward movement process (corresponding to the first movement process) in which the second motor M2 moves the pressing roller 224 to the upstream side in the conveying direction from a state in which the pressing roller 224 is pressing the workpiece W against the conveying surface 211a of the conveying belt 211 at the second position P2 (an example of a predetermined position). By performing this first backward movement process, the control unit 90 causes the workpiece W located upstream of the second position P2 in the conveying direction (more precisely, a predetermined length of workpiece W starting from the second position P2 and upstream of the second position P2) to adhere to the conveying surface 211a.

[0073] With this configuration, the pressing member (in this example, the pressing roller 224) moves from downstream to upstream while pressing the workpiece W against the transport surface 211a, so that the pressing position of the pressing member gradually moves from downstream to upstream, and the workpiece W is attached to the transport surface 211a. Therefore, compared to the conventional method of attaching the workpiece W to the transport surface 211a while pulling the workpiece W between the pressing member and the transport surface 211a, the possibility of excessive tension being generated on the workpiece W can be reduced. In particular, in this embodiment, since the pressing roller 224 is used as the pressing member, the workpiece W can be smoothly attached to the transport surface 211a as the pressing roller 224 rolls along the workpiece W. Therefore, compared to the conventional method of pulling the workpiece W between the pressing roller 224 and the transport surface 211a (compared to the case where the pressing position does not move), the possibility of localized excessive tension being applied to the workpiece W can be reduced. As a result, the possibility of the workpiece W being attached to the transport surface 211a in an elongated state in the transport direction can be reduced. Consequently, the possibility of shrinkage of the workpiece W or image distortion occurring when the workpiece W is peeled off the transport surface 211a after printing can be reduced.

[0074] In this embodiment, the backward movement process involves moving the press roller 224 from the downstream side to the upstream side in the conveying direction using the second motor M2, while the drive of the conveyor belt 211 by the first motor M1 is stopped.

[0075] With this configuration, the press roller 224 is moved in the conveying direction while the conveyor belt 211 is stopped, thus minimizing the possibility of excessive tension being generated in the workpiece W. That is, for example, if the press roller 224 is moved from downstream to upstream while the conveyor belt 211 is rotated in the forward direction (arrow direction in Figure 2), the direction of movement of the press roller 224 and the direction of movement of the conveyor belt 211 are opposite to each other, so the workpiece W may be pulled on both sides in the conveying direction. In contrast, with the above configuration, the press roller 224 is moved while the conveyor belt 211 is stopped, thus avoiding this problem and reducing the possibility of excessive tension being generated in the workpiece W.

[0076] In this embodiment, the control unit 90 can further perform a belt feeding process (corresponding to a second movement process) which moves the conveying surface 211a from the upstream side to the downstream side in the conveying direction by driving the conveying belt 211 with the first motor M1, and a forward movement process (corresponding to a third movement process) which moves the pressing roller 224 from the upstream side to the downstream side in the conveying direction.

[0077] With this configuration, the process of attaching the workpiece W includes the operation of returning the pressing roller 224 from the upstream side to the downstream side in the conveying direction, thus reducing the risk of the pressing roller 224 going too far downstream in the conveying direction.

[0078] Specifically, in this embodiment, during the forward movement process, the pressing roller 224 is moved from the first position P1 to the second position P2, which is downstream of the first position P1.

[0079] With this configuration, the pressing roller 224 can be returned to the first position P1 and the workpiece W can be attached to the transport surface 211a from the same position, thereby improving the reproducibility of the attachment operation. Furthermore, by moving the transport surface 211a from the upstream side to the downstream side in the transport direction, it is not necessary to move the pressing roller 224 excessively upstream in the transport direction of the workpiece W, and the movement range of the pressing roller 224 can be kept within a predetermined range. This simplifies the movement mechanism of the pressing roller 224.

[0080] In this embodiment, during the forward movement process, the pressing roller 224 is moved in synchronization with the movement of the conveying surface 211a of the conveying belt 211.

[0081] With this configuration, by moving the pressing roller 224 forward in synchronization with the movement of the conveying surface 211a of the conveying belt 211, it is possible to suppress the tension acting on the workpiece W when the workpiece W starts to move. Therefore, the possibility of the workpiece W sticking to the conveying surface 211a of the conveying belt 211 while stretched can be reduced. Furthermore, since the attachment of the workpiece W to the conveying surface 211a is achieved by the pressing roller 224 rolling along the upper surface of the workpiece W from the second position P2 to the first position P1, the possibility of suppressing the stretching of the workpiece W is increased compared to the case where the workpiece W is pulled between the pressing roller 1224 and the conveying surface 1211a of the conveying belt 211 as shown in the comparative example (see Figure 5).

[0082] In this regard, we will first explain the conventional problems with reference to Figure 5, and then explain in detail the effects of the configuration of this embodiment with reference to Figures 6A and 6B. Figure 5 schematically shows the tension state acting on the workpiece W during belt feeding in a printing apparatus according to a comparative example in which the pressing roller 224 and the second guide roller 223 are fixed. Note that in Figure 5, the components corresponding to the printing apparatus 1 of this embodiment are indicated by a reference numeral with 1000 added.

[0083] First, as a premise, the greatest tension acts on the workpiece W at the moment the drive control unit 901 starts the feed movement of the conveyor belt 211 with the first motor M1. In particular, in a configuration like this embodiment, where the weight of the dancer rollers (the first tension roller 103 and the third tension roller 105 in this example) is applied to the workpiece W in the recording medium supply device 100, the tension becomes significantly larger because it is necessary to pull the workpiece W from the upstream side to the downstream side in the conveying direction against the weight of the dancer rollers.

[0084] Therefore, in Figure 5, the tension T1 acting on the workpiece W at the moment the transport belt 1211 starts moving is indicated by an arrow in the comparative example printing apparatus. In the comparative example printing apparatus, a large tension T1 acts on the workpiece W when the transport belt 211 starts moving, and at the same time the workpiece W is pulled between the pressing roller 224 and the transport surface 211a of the transport belt 211. As a result, the workpiece W is stretched in the length direction (along the transport direction) by the tension T1 and stuck to the transport surface 211a. For this reason, when the workpiece W is peeled off the transport surface 211a, the workpiece W shrinks in the length direction, which may reduce the quality of the printed image.

[0085] In contrast, the printing apparatus 1 of this embodiment is more likely to avoid such problems by performing the above-described attachment control. The reason for this will be explained with reference to Figures 6A and 6B. Figure 6A schematically shows the tension T2 acting on the workpiece W during the belt stopping process. Figure 6B schematically shows the tension acting on the conveyor belt 211 from the first position to the second position when the pressing roller 224 is moved by the forward movement process.

[0086] As shown in Figure 6A, the tension T2 acting on the workpiece W during the belt stopping process is smaller than the tension T1 acting on the workpiece W during the feeding movement of the workpiece W in the comparative example described above (see Figure 5).

[0087] In the adhesive control of this embodiment, when the belt feeding process is executed from the belt stopped state shown in Figure 6A (i.e., when the feeding movement of the workpiece W begins), the forward movement process of the pressing roller 224 and the second guide roller 223 (see Figure 6B) is executed in synchronization with the workpiece W.

[0088] During this forward movement process, as shown in Figure 6B, the pressing roller 224 and the second guide roller 223 move forward (from left to right in the figure) in synchronization with the movement of the conveyor belt 211. Therefore, the positions of the virtual points on the workpiece W, indicated by the black circles B1 to B4 in the figure, do not change in the length direction of the workpiece. That is, the tension acting on the workpiece W remains at T1. Consequently, the forward movement process is completed without the workpiece W being stretched in the length direction. At the stage when this forward movement process is completed, the workpiece W is not yet attached to the conveyor surface 211a. In this embodiment, after this forward movement process is completed, the control unit 90 executes a backward movement process to attach the workpiece W to the conveyor surface 211a. When the backward movement process is executed, the pressing roller 224 moves backward together with the second guide roller 223 from the second position P2 to the first position P1.

[0089] In this manner, the pressing roller 224 rolls along the upper surface of the workpiece W, adhering the workpiece W to the transport surface 211a. Therefore, unlike the comparative example (see Figure 5), the workpiece W is not forcibly pulled between the pressing roller 224 and the transport surface 211a. As a result, compared to the comparative example, the tension acting on the workpiece W when the pressing roller 224 adheres the workpiece W to the transport surface 211a can be reduced. Thus, the possibility of the workpiece W being stretched in the longitudinal direction and adhering to the transport surface 211a during adhesion can be reduced.

[0090] Furthermore, with the above configuration, when the conveyor belt 211 is stopped (i.e., during the belt stopping process), the pressing roller 224 does not remain in one place but moves from the second position P2 to the first position P1, thus reducing the possibility of indentations from the pressing roller 224 being left on the workpiece W.

[0091] Furthermore, in this embodiment, the control unit 90 executes the backward movement process after the forward movement process.

[0092] With this configuration, after the workpiece W is attached to the transport surface 211a by the backward movement process, the possibility of excessive tension being generated on the workpiece W can be reduced by performing the forward movement process. Furthermore, this forward movement process can also be used as an operation to return the pressing roller 224 to the first position P1. As a result, there is no need to perform a separate dedicated movement to return the pressing roller 224 to the first position P1, and unnecessary movement can be suppressed while performing the next attachment process, thereby improving the efficiency of the attachment process.

[0093] Furthermore, in this embodiment, during the forward movement process, the portion of the workpiece W that has adhered to the conveying surface 211a of the conveying belt 211 due to the upstream movement of the pressing roller 224 in the conveying direction moves downstream while remaining attached to the conveying surface 211a (see Figures 6A and 6B).

[0094] With this configuration, the portion of the workpiece W that is already attached to the conveying surface 211a moves downstream while remaining attached to the conveying surface 211a, thus reducing the possibility of shear force acting on that portion in the conveying direction from the conveying surface 211a. This reduces the risk of excessive tension acting on that portion in the conveying direction, which could cause the workpiece W to stretch.

[0095] Furthermore, in this embodiment, during the forward movement process, the portion of the workpiece W upstream of the attached portion in the transport direction moves downstream in the transport direction without being attached to the transport surface 211a.

[0096] With this configuration, the portion of the workpiece W that is not attached to the conveying surface 211a moves downstream in the conveying direction together with the conveying belt 211, thereby reducing the risk of excessive tension acting on that portion. This reduces the risk of the workpiece W stretching in the conveying direction.

[0097] When the control unit 90 performs backward movement processing and forward movement processing, it moves the second guide roller 223 in the direction of movement of the press roller 224 using the second motor M2 (corresponding to the third drive unit which is configured as a drive source common with the second drive unit).

[0098] This configuration reduces the risk of excessive tension acting on the portion of the workpiece W located between the pressing roller 224 and the second guide roller 223.

[0099] Furthermore, in this embodiment, when the control unit 90 moves the second guide roller 223 in the direction of movement of the press roller 224, it moves the guide roller 223 in conjunction with the movement of the press roller 224.

[0100] With this configuration, the second guide roller 223 moves in conjunction with the movement of the pressing roller 224, thus reducing the risk of excessive tension being applied to the workpiece W.

[0101] In this embodiment, the second guide roller 223 reduces the entry angle at which the workpiece W enters the space between the pressing roller 224 and the conveying surface 211a, compared to the case where the second guide roller 223 is absent.

[0102] According to this, the risk of excessive tension being generated in the workpiece W due to the workpiece W being pulled in at a sharp angle between the second guide roller 223 and the transport surface 211a can be reduced. Therefore, the possibility of shrinkage of the workpiece W or image distortion occurring when the workpiece W is peeled off the transport surface 211a after printing can be reduced.

[0103] Specifically, in this embodiment, the second guide roller 223 causes the workpiece W to enter diagonally from the upstream side in the conveying direction between the pressing roller 224 and the conveying surface 211a of the conveying belt 211, when viewed from the X direction.

[0104] With this configuration, by introducing the workpiece W at an angle to the pressing roller 224, the risk of the workpiece W's orientation changing abruptly at the pressing position of the pressing roller 224 is reduced, thereby reducing the risk of excessive tension being applied to the workpiece W.

[0105] Furthermore, the second guide roller 223 moves in conjunction with the pressure roller 224, thereby reducing the tension acting on the workpiece W compared to when the second guide roller 223 is stopped.

[0106] This reduces the risk of the workpiece W being stretched in the transport direction between the pressing roller 224 and the second guide roller 223. Therefore, it reduces the possibility of shrinkage of the workpiece W or image distortion occurring when the workpiece W is peeled off the transport surface 211a after printing.

[0107] In this embodiment, the printing apparatus 1 has a second guide roller 223 located upstream of the press roller 224 in the transport direction and guiding the workpiece W by contacting the upper surface (i.e., the printing side) of the workpiece W. When the control unit 90 performs forward and backward movement processing of the press roller 224, the second motor M2 moves the second guide roller 223 in conjunction with the movement of the press roller 224 while maintaining the relative positional relationship between the second guide roller 223 and the press roller 224.

[0108] With this configuration, the second guide roller 223 moves together with the pressing roller 224 while maintaining its relative positional relationship with the pressing roller 224, thus reducing the possibility of increased tension acting on the workpiece W between the second guide roller 223 and the pressing roller 224. Therefore, the possibility of the workpiece W being stuck to the conveying surface 211a in an elongated state is reduced.

[0109] In this embodiment, the motor that drives the press roller 224 (corresponding to the second drive unit) and the motor that drives the second guide roller 223 (corresponding to the third drive unit) are both a single common second motor M2 (see Figure 1).

[0110] This configuration makes it possible to reduce the number of parts and lower costs compared to the case where the pressing roller 224 and the second guide roller 223 are each driven by separate motors.

[0111] Furthermore, in this embodiment, when the conveyor belt 211 is moved from the upstream side to the downstream side in the conveying direction during the execution of the belt feeding process (second movement process), if the acceleration of the conveyor belt 211 until it reaches a predetermined set movement speed is taken as the reference acceleration, then the acceleration when the push roller 224 is accelerated to a predetermined set movement speed during the execution of the reverse movement process (first movement process) is smaller than the reference acceleration (see Figure 4). Also, when the conveyor belt 211 is moved from the upstream side to the downstream side in the conveying direction during the execution of the belt feeding process (second movement process), if the deceleration when the conveyor belt 211 decelerates after it reaches a predetermined set movement speed to stop is taken as the reference deceleration, then the absolute value of the deceleration of the push roller 224 when it decelerates after it reaches a predetermined set movement speed to stop during the execution of the reverse movement process (first movement process) is smaller than the absolute value of the reference deceleration (see Figure 4).

[0112] With this configuration, during the backward movement process, the pressing roller 224 can be slowly rolled along the upper surface of the workpiece W, so that the workpiece W can be adhered to the conveying surface 211a without increasing the tension acting on the workpiece W as much as possible. Therefore, the possibility of the workpiece W adhering to the conveying surface 211a in an extended state can be reduced.

[0113] Furthermore, in this embodiment, the speed profile of the pressing roller 224 during the execution of the forward movement process (lower diagram in Figure 4) and the speed profile of the conveyor belt 211 during the execution of the belt feeding process (middle diagram in Figure 4) are equivalent (the same or include a predetermined error).

[0114] With this configuration, when the forward movement process is executed, the press roller 224 (and the second guide roller 223) can be moved with the same speed profile as the feed movement of the conveyor belt 211. This reduces the possibility of unintended tension acting on the workpiece W due to a speed difference between the conveyor belt 211 and the press roller 224. Consequently, it reduces the possibility of the workpiece W becoming adhered to the conveying surface 211a of the conveyor belt 211 in a contracted state due to tension. Note that the speed profile of the press roller 224 and the speed profile of the conveyor belt 211 being equivalent does not mean that they are exactly the same, but that they may include a predetermined error (for example, an error of ±10% or less).

[0115] (Embodiment 2) Figure 7 is a diagram corresponding to Figure 2 showing Embodiment 2. In the following embodiments, the same reference numerals are used for components that are the same as in Embodiment 1, and detailed descriptions are omitted. In this embodiment, the arrangement layout of the pressing roller 224 and the second guide roller 223 differs from that of Embodiment 1, and it also differs from Embodiment 1 in that a tension relaxation process is performed during adhesive control.

[0116] First, we will explain the differences in the arrangement layout of the pressing roller 224 and the second guide roller 223 compared to Embodiment 1.

[0117] In this embodiment, as shown in Figure 7, the position of the second guide roller 223 when the press roller 224 is in the first position P1 and the position of the second guide roller 223 when the press roller 224 is in the second position P2 (see the dashed line in Figure 7) are symmetrical with respect to the straight line K, which will be described later, when viewed from the X direction. The straight line K is defined as a straight line that touches the front half of the first guide roller 222 in the rotational direction and extends in the vertical direction. Specifically, the extension direction of the workpiece W guided by the second guide roller 223 when the press roller 224 is in the first position P1 and the extension direction of the workpiece W guided by the second guide roller 223 when the press roller 224 is in the second position P2 intersect the straight line K at the same angle θ.

[0118] Next, the tension relief process of this embodiment will be described. In this embodiment, in order to realize this tension relief process, the first guide roller 222 is made rotatable by a third motor M3 (an example of a fourth drive unit). The third motor M3 is controlled by a drive control unit 901.

[0119] The drive control unit 901 controls the third motor M3 to rotate the first guide roller 222 in the forward direction C at a predetermined speed when executing the backward movement process of the press roller 224 and the second guide roller 223. As a result, the workpiece W is pushed forward in the direction of rotation by the first guide roller 222. This reduces the possibility that the tension acting on the workpiece W between the first guide roller 222 and the second guide roller 223 will increase during the backward movement process (i.e., while the press roller 224 is rolling backward on the top surface of the workpiece W). Mechanically, this tension is equal to the tension acting on the workpiece W between the press roller 224 and the second guide roller 223. Therefore, this reduces the possibility that the workpiece W will be stretched between the press roller 224 and the second guide roller 223. Thus, the possibility that the workpiece W will stick to the conveying surface 211a of the conveying belt 211 in an stretched state can be further reduced.

[0120] In order to improve the feasibility of the tension relief process, it is preferable to ensure that the workpiece W is reliably moved by rotating the first guide roller 222 in the forward direction. For this purpose, a grip roller may be used as the first guide roller 222. A grip roller is a roller having an outer surface with a shape, material, etc. that can prevent the workpiece W from slipping.

[0121] Furthermore, it is preferable that the forward rotational speed of the first guide roller 222 be slow so as not to cause a sudden increase in the tension of the workpiece W between the first guide roller 222 and the widening roller 221. For example, the forward peripheral speed of the first guide roller 222 may be less than the moving speed (peripheral speed) of the conveyor belt 211 during the belt feeding process.

[0122] Furthermore, the printing apparatus 1 may have a guide bar 227 between the first guide roller 222 and the second guide roller 223, as shown by the dashed line in Figure 7. The guide bar 227 may be a simple rod-shaped member or a rotatable roller member. This reduces the possibility that the behavior of the workpiece W may become unstable when tension is relieved by the rotation of the first guide roller 222 in the forward direction C.

[0123] [Effects of Embodiment 2] As described above, in this embodiment, when the pressing roller 224 and the second guide roller 223 are moved backward (first movement process), the control unit 90 can perform a process to rotate the first guide roller 222, which is located upstream of the second guide roller 223, in the forward direction C (i.e., the direction in which the workpiece W is sent from the upstream side to the downstream side in the transport direction) at a predetermined speed.

[0124] This configuration reduces the possibility of an increase in the tension acting on the workpiece W between the first guide roller 222 and the second guide roller 223 while the pressing roller 224 is being moved backward.

[0125] (Other Embodiments) Although a printing apparatus 1 according to an embodiment of the present disclosure has been described above, the present disclosure is not limited thereto.

[0126] (1) In each of the above embodiments, the average moving speed of the pressing roller 224 and the second guide roller 223 during the backward movement process (the absolute value of the speed obtained by dividing the distance traveled by each roller by time) is kept constant regardless of the dimensions of the workpiece W, but this is not limited to this. The control unit 90 may reduce the average moving speed of the pressing roller 224 and the second guide roller 223 during the execution of the backward movement process (first movement process) as the dimensions of the workpiece W in the width direction (media width direction) perpendicular to the conveying direction become larger. In other words, generally, the larger the dimensions of the workpiece W in the width direction, the more likely wrinkles and the like are to occur on the workpiece W. Focusing on this, the above configuration is configured to move the pressing roller 224 and the second guide roller 223 backward more slowly as the dimensions of the workpiece W in the width direction become larger. This reduces the possibility of wrinkles and the like occurring on the workpiece W when it is adhered to the conveying surface 211a of the conveying belt 211. Furthermore, by slowly moving the pressing roller 224 and the second guide roller 223 backward, the time between the completion of the backward movement and the start of the forward movement of the pressing roller 224 and the second guide roller 223, that is, the stopping time of the pressing roller 224 and the second guide roller 223, can be shortened. Therefore, the possibility of pressure marks from the pressing roller 224 being left on the surface of the workpiece W while the pressing roller 224 is stopped can be reduced. In order to reduce the average moving speed of the pressing roller 224 and the second guide roller 223, for example, the set moving speed (specifically, its absolute value) of each roller 224, 223 can be reduced, but this is not limited to this.

[0127] (2) In each of the above embodiments, the average moving speeds of the pressing roller 224 and the second guide roller 223 during the forward movement process (the absolute value of the speed obtained by dividing the distance traveled by each roller by the travel time) and the average moving speed of the conveyor belt 211 are set to be equivalent (the same or including a predetermined error), but the invention is not limited to this. The control unit 90 may make the average moving speed of the conveyor belt 211 and the average moving speed of the pressing roller 224 different when the forward movement process is executed. With this configuration, when the pressing roller 224 is moved forward, the relative positional relationship in the Y direction between the workpiece W and the pressing roller 224 changes over time. In other words, the contact position of the pressing roller 224 with respect to the workpiece W changes over time. Therefore, the possibility of pressure marks from the pressing roller 224 being left on the workpiece W can be reduced. As an example, the average moving speed of the pressing roller 224 may be set to 80% or more and 95% or less of the average moving speed of the conveyor belt 211. The average travel speed of the press roller 224 and the second guide roller 223 can be controlled, for example, by changing the set travel speed (specifically, its absolute value) of each roller 224, 223, but is not limited to this.

[0128] (3) In each of the above embodiments, a common motor M2 is used as the drive unit for driving the press roller 224 and the second guide roller 223 in the Y direction, but this is not limited to this. The press roller 224 and the second guide roller 223 may each be driven by separate drive motors. In this case, the drive motor that drives the press roller 224 corresponds to the second drive unit, and the drive motor that drives the second guide roller 223 corresponds to the third drive unit. Furthermore, the drive unit is not limited to a motor, but may be a linear actuator such as an electromagnetic solenoid, for example.

[0129] (4) In each of the above embodiments, the second guide roller 223 is moved together with the press roller 224, but this is not limited to this. The position of the second guide roller 223 may be fixed. The second guide roller 223 has the function of reducing the tension applied to the workpiece W (e.g., fabric) by reducing the angle of entry with respect to the conveying surface 211a when the workpiece W is being fed (conveyed). The second guide roller 223 may also move at a different timing than the movement timing of the press roller 224. The second guide roller 223 may also move along a different path than the movement path of the press roller 224. Furthermore, the second guide roller 223 is not necessarily required. The printing apparatus 1 of this disclosure also includes configurations that do not have the second guide roller 223.

[0130] (5) In each of the above embodiments, the control unit 90 moves the guide roller 223 (an example of a guide member) in conjunction with the movement of the press roller 224 (an example of a press member) by the third motor M3 when performing both the reversing movement process and the forward movement process, but is not limited to this. In various conceivable embodiments, the guide member may be linked only in the forward movement process, or the guide member may be linked only in the reversing movement process.

[0131] (6) In each of the embodiments described above, a guide roller 223 was given as an example of a guide member, but the invention is not limited to this. That is, the guide member does not necessarily have to be a roller, and may be, for example, a plate or the like that is inclined at an angle with respect to the conveying surface 211a when viewed from the X direction. In other words, the guide member may have any configuration as long as it has the function of reducing the entry angle of the workpiece W with respect to the pressing member (pressing roller 224 in this example) (for example, the function of reducing it to an angle smaller than 90°).

[0132] (7) In each of the above embodiments, an endless conveying belt 211 was given as an example of a conveying member, but the conveying member is not limited to this. The conveying member may be a roller conveyor or the like having a plurality of adjacent rollers.

[0133] (8) In each of the above embodiments, a pressing roller 224 was given as an example of a pressing member, but the invention is not limited to this. The pressing member may be, for example, a non-rotatable block or plate-shaped body.

[0134] (9) In each of the above embodiments, the conveying surface 211a of the conveying belt 211 is capable of adhering the workpiece W to it by adhesive, but is not limited thereto. The manner in which the workpiece W is attached to the conveying surface 211a includes manners in which the workpiece W is strongly pressed against the conveying surface 211a to fix it in place, and manners in which the workpiece W is attracted to the conveying surface 211a by applying negative pressure from the inside of the conveying belt 211. In other words, the term "attachment" in this disclosure is not limited to adhesive, but can be any manner (for example, fixing or adsorption) that makes it possible to attach the workpiece W to the conveying surface 211a.

[0135] (10) In each of the above embodiments, the forward movement process of the press roller 224 is performed in synchronization with the feed movement of the conveyor belt 211. However, synchronization here is not limited to a configuration in which the execution timing of the forward movement process perfectly matches the movement timing of the conveyor belt 211, and there may be some timing difference. For example, the press roller 224 may start moving forward before the conveyor belt 211. Also, regarding the end time of the movement of the press roller 224, for example, the press roller 224 may finish moving forward after the end time of the conveyor belt 211.

[0136] (11) In each of the above embodiments, the pressing roller 224 can press the workpiece W against the conveying surface 211a of the conveying belt 211 during both forward and backward movement processes, but is not limited thereto. For example, during the forward movement process, the pressing roller 224 may be kept lifted away from the workpiece W (conveying surface 211a).

[0137] (12) In each of the embodiments described above, the attachment control is described in an example in which the attachment control includes a belt feed process (corresponding to the second movement process), a belt stop process, a forward movement process (corresponding to the third movement process), and a backward movement process (corresponding to the first movement process), but is not limited thereto. That is, the attachment control only needs to include a process corresponding to the first movement process (i.e., a process in which the pressing member presses the recording medium against the transport surface of the transport member, and the pressing member is moved from the downstream side to the upstream side in the transport direction to attach the recording medium to the transport surface), and the presence, order, or content of other movement processes is not limited.

[0138] (13) In each of the above embodiments, the reverse movement process (see Figure 4, etc.) is performed with the drive of the conveyor belt 211 stopped, but the invention is not limited to this. For example, the reverse movement process may be performed while the conveyor belt 211 is driven in the forward direction (direction of the arrow in Figure 2). This improves the speed at which the workpiece W is attached to the conveyor surface 211a compared to when the drive of the conveyor belt 211 is stopped. Conversely, the reverse movement process may be performed while the conveyor belt 211 is driven in the reverse direction (opposite direction to the direction of the arrow in Figure 2). This causes the conveyor surface 211a of the conveyor belt 211 and the pressing roller 224 to move in the same direction (from right to left in the example of Figure 2) while the workpiece W is pressed against the conveyor surface 211a. This reduces the speed difference between the conveyor surface 211a and the pressing roller 224 when the workpiece W is attached, thereby reducing the possibility of excessive tension being applied to the workpiece W.

[0139] (14) In each of the above embodiments, an example was described in which the drive control unit 901 of the control unit 90 controls the operation of the first motor M1 (an example of a first drive unit) and the second motor M2 (an example of a second drive unit), but the control unit 90 is not limited to this. The control unit 90 may have a first drive control unit that controls the first motor M1 and a second drive control unit that controls the second motor M2. Also, in each of the above embodiments, an example was described in which the control unit 90 is a single control device, but the control unit 90 is not limited to this. The control unit 90 may have a plurality of control devices. In other words, the control unit 90 may be in any form as long as it is capable of controlling the operation of the first drive unit and the second drive unit.

[0140] This disclosure includes the following components (1) to (25).

[0141] (1) A printing apparatus comprising: a transport member having a transport surface on which a recording medium can be attached, and transporting the recording medium by moving the transport surface along a predetermined transport direction; a pressing member positioned opposite the transport surface of the transport member and capable of pressing the recording medium against the transport surface; a first drive unit that drives the transport member so that the transport surface of the transport member can move along the transport direction; a second drive unit that can move the pressing member along the transport direction; and a control unit that controls the operation of the first drive unit and the second drive unit, wherein the control unit is capable of performing a first movement process in which, from a state in which the pressing member presses the recording medium against the transport surface at a predetermined position in the transport direction, the second drive unit moves the pressing member upstream in the transport direction.

[0142] (2) In the printing apparatus of (1) above, the first movement process may be performed with the drive of the transport member by the first drive unit stopped.

[0143] (3) In the printing apparatus of (1) or (2) above, the control unit may further perform a second movement process in which the transport surface of the transport member is moved from the upstream side to the downstream side in the transport direction by driving the transport member with the first drive unit, and a third movement process in which the press member is moved from the upstream side to the downstream side in the transport direction by driving the press member with the second drive unit.

[0144] (4) In the printing apparatus of (3) above, the third movement process may be a process of moving the pressing member from the first position to the second position, which is the predetermined position downstream of the first position in the transport direction.

[0145] (5) In the printing apparatus of (3) or (4) above, in the third movement process, the pressing member may be moved in synchronization with the movement of the transport surface of the transport member.

[0146] (6) In any one of the printing apparatuses described in (3) to (5) above, the control unit may perform the first movement process after the third movement process.

[0147] (7) In any one of the printing apparatuses described in (3) to (6) above, in the second moving process, the portion of the recording medium that has adhered to the transport surface by the first moving process may be moved downstream while still adhering to the transport surface.

[0148] (8) In any one of the printing apparatuses described in (3) to (7) above, in the second movement process, the portion of the recording medium upstream in the transport direction from the portion attached to the transport surface by the first movement process may move downstream in the transport direction without being attached to the transport surface.

[0149] (9) Any one of the printing apparatuses described in (3) to (8) above may further include a guide member located upstream of the pressing member in the transport direction and guiding the recording medium, and a third drive unit that drives the guide member so as to be movable in the transport direction.

[0150] (10) In the printing apparatus described in (9) above, when the control unit performs at least one of the first movement process and the third movement process, the third drive unit may move the guide member in the direction of movement of the pressing member in conjunction with the movement of the pressing member.

[0151] (11) In the printing apparatus of (9) or (10) above, the entry angle at which the recording medium enters the space between the pressing member and the transport surface may be lower when the guide member is present than when the guide member is absent.

[0152] (12) In any one of the printing apparatuses described in (9) to (11), the guide member may be positioned such that, when viewed from a width direction perpendicular to the transport direction, the recording medium is brought in diagonally between the pressing member and the transport surface from the upstream side in the transport direction.

[0153] (13) In any one of the printing apparatuses described in (9) to (12) above, the guide member may be moved by the third drive unit in the direction of movement of the pressing member, thereby reducing the tension acting on the recording medium compared to the state in which the guide member is stopped.

[0154] (14) In any one of the printing apparatuses described in (9) to (13), the control unit may move the guide member in the direction of movement of the press member by the third drive unit while maintaining the relative positional relationship between the guide member and the press member.

[0155] (15) In any one of the printing apparatuses described in (9) to (14) above, the second drive unit and the third drive unit may be a single common drive unit.

[0156] (16) In any one of the printing apparatuses described in (1) to (15), the control unit may reduce the average moving speed of the pressing member when the first moving process is executed, as the size of the media width direction, which is perpendicular to the transport direction in the recording medium, increases.

[0157] (17) In any one of the printing apparatuses described in (3) to (15) above, the control unit may make the average moving speed of the transport member and the average moving speed of the pressing member different when executing the third moving process.

[0158] (18) In any one of the printing apparatuses described in (3) to (15) above, when the transport surface of the transport member is moved from the upstream side to the downstream side in the transport direction during the execution of the second movement process, the acceleration of the transport member until it reaches a predetermined set movement speed is defined as the reference acceleration, and the acceleration when the pressing member is accelerated to a predetermined set movement speed during the execution of the first movement process may be less than the reference acceleration.

[0159] (19) In any one of the printing apparatuses described in (3) to (15) above, when the transport surface of the transport member is moved from the upstream side to the downstream side in the transport direction during the execution of the second movement process, the deceleration when the transport member decelerates after reaching a predetermined set movement speed to stop is defined as the reference deceleration, and the absolute value of the deceleration of the pressing member when the pressing member decelerates after reaching a predetermined set movement speed to stop during the execution of the first movement process may be smaller than the absolute value of the reference deceleration.

[0160] (20) In any one of the printing apparatuses described in (3) to (15) above, the speed profile of the pressing member during the execution of the third movement process and the speed profile of the transport member during the execution of the second movement process may be equivalent.

[0161] (21) In any one of the printing apparatuses described in (9) to (15) above, the apparatus further comprises a guide roller positioned upstream of the guide member in the transport direction of the recording medium and guiding the recording medium, and a fourth drive unit that rotationally drives the guide roller, wherein the control unit may, when executing the first movement process, perform a process by which the fourth drive unit rotationally drives the guide roller in a direction that sends the recording medium from the upstream side to the downstream side in the transport direction.

[0162] (22) In the printing apparatus of (21) above, the position of the guide roller is fixed, and its orientation during transport of the recording medium may be changed.

[0163] (23) A method of adhesion relating to another aspect of the present disclosure is a method of adhesion for a recording medium to be attached to a printing apparatus comprising a transport member having a transport surface to which a recording medium can be attached, and transporting the recording medium by moving the transport surface along a predetermined transport direction, and a pressing member positioned opposite the transport surface of the transport member and capable of pressing the recording medium against the transport surface, wherein the method of adhesion for attaching the recording medium to the transport surface includes a first step of moving the pressing member upstream in the transport direction from a state in which the recording medium is pressed against the transport surface by the pressing member at a predetermined position in the transport direction.

[0164] (24) In the adhesion method described in (23), the first step may be performed with the drive of the transport member stopped.

[0165] (25) The adhesion method according to (23) or (24) may further include a second step of driving the conveying member to move the conveying surface of the conveying member from the upstream side to the downstream side in the conveying direction, and a third step of moving the pressing member from the upstream side to the downstream side in the conveying direction.

Claims

1. A printing apparatus comprising: a transport member having a transport surface on which a recording medium can be attached, and transporting the recording medium by moving the transport surface along the transport direction of the recording medium; a pressing member positioned opposite the transport surface of the transport member and capable of pressing the recording medium against the transport surface; a first drive unit that drives the transport member so that the transport surface of the transport member can move along the transport direction of the recording medium; a second drive unit capable of moving the pressing member along the transport direction; and a control unit that controls the operation of the first drive unit and the second drive unit, wherein the control unit is capable of executing a first movement process in which, from a state in which the pressing member has pressed the recording medium against the transport surface at a predetermined position in the transport direction, the second drive unit moves the pressing member upstream in the transport direction.

2. A printing apparatus according to claim 1, wherein the first movement process is performed with the drive of the transport member by the first drive unit stopped.

3. A printing apparatus according to claim 1 or 2, wherein the control unit is further capable of performing a second movement process, which involves driving the transport member with the first drive unit to move the transport surface of the transport member from the upstream side to the downstream side in the transport direction, and a third movement process, which involves driving the pressing member with the second drive unit to move the pressing member from the upstream side to the downstream side in the transport direction.

4. A printing apparatus according to claim 3, wherein the third movement process is a process of moving the pressing member from a first position to a second position, which is the predetermined position downstream of the first position in the transport direction.

5. A printing apparatus according to claim 3 or 4, wherein in the third movement process, the pressing member is moved in synchronization with the movement of the transport surface of the transport member.

6. A printing apparatus according to any one of claims 3 to 5, wherein the control unit performs the first movement process after the third movement process.

7. A printing apparatus according to any one of claims 3 to 6, wherein in the second movement process, the portion of the recording medium that has adhered to the transport surface by the first movement process moves downstream while remaining adhered to the transport surface.

8. A printing apparatus according to any one of claims 3 to 7, wherein in the second movement process, the portion of the recording medium upstream in the transport direction from the portion attached to the transport surface by the first movement process moves downstream in the transport direction without being attached to the transport surface.

9. A printing apparatus according to any one of claims 3 to 8, further comprising: a guide member located upstream of the pressing member in the transport direction and guiding the recording medium; and a third drive unit that drives the guide member so as to be movable in the transport direction.

10. A printing apparatus according to claim 9, wherein the control unit, when performing at least one of the first movement process and the third movement process, moves the guide member in the direction of movement of the pressing member in conjunction with the movement of the pressing member, using the third drive unit.

11. A printing apparatus according to claim 9 or 10, wherein the entry angle at which the recording medium enters the space between the pressing member and the transport surface is lower when the guide member is present than when the guide member is absent.

12. A printing apparatus according to any one of claims 9 to 11, wherein the guide member, when viewed from a width direction perpendicular to the transport direction, causes the recording medium to enter the space between the pressing member and the transport surface at an angle from the upstream side in the transport direction.

13. A printing apparatus according to any one of claims 9 to 12, wherein the guide member is moved by the third drive unit in the direction of movement of the pressing member, thereby reducing the tension acting on the recording medium compared to the state in which the guide member is stopped.

14. A printing apparatus according to any one of claims 9 to 13, wherein the control unit moves the guide member in the direction of movement of the pressing member by the third drive unit while maintaining the relative positional relationship between the guide member and the pressing member.

15. A printing apparatus according to any one of claims 9 to 14, wherein the second drive unit and the third drive unit are a single common drive unit.

16. A printing apparatus according to any one of claims 1 to 15, wherein the control unit reduces the average moving speed of the pressing member when the first moving process is executed, as the dimension in the media width direction, which is perpendicular to the transport direction of the recording medium, increases.

17. A printing apparatus according to any one of claims 3 to 15, wherein the control unit makes the average moving speed of the transport member and the average moving speed of the pressing member different when the third moving process is executed.

18. A printing apparatus according to any one of claims 3 to 15, wherein when the transport surface of the transport member is moved from the upstream side to the downstream side in the transport direction during the execution of the second movement process, the acceleration of the transport member until the transport member reaches a predetermined set movement speed is defined as the reference acceleration, and the acceleration when the pressing member is accelerated to a predetermined set movement speed during the execution of the first movement process is smaller than the reference acceleration.

19. A printing apparatus according to any one of claims 3 to 15, wherein when the transport surface of the transport member is moved from the upstream side to the downstream side in the transport direction during the execution of the second movement process, the deceleration when the transport member decelerates after reaching a predetermined set movement speed and then stops is defined as the reference deceleration, and the absolute value of the degree of deceleration of the pressing member when the pressing member decelerates after reaching a predetermined set movement speed and then stops during the execution of the first movement process is smaller than the absolute value of the reference deceleration.

20. A printing apparatus according to any one of claims 3 to 15, wherein the speed profile of the pressing member during the execution of the third movement process and the speed profile of the transporting member during the execution of the second movement process are equivalent.

21. A printing apparatus according to any one of claims 9 to 15, further comprising: a guide roller positioned upstream of the guide member in the transport direction of the recording medium and guiding the recording medium; and a fourth drive unit for rotationally driving the guide roller, wherein the control unit is capable of performing a process by which the fourth drive unit rotates the guide roller in a direction that sends the recording medium from the upstream side to the downstream side in the transport direction when executing the first movement process.

22. A printing apparatus according to claim 21, wherein the guide roller is fixed in position and changes the orientation of the recording medium during transport.

23. A printing apparatus comprising a transport member having a transport surface on which a recording medium can be attached, and transporting the recording medium by moving the transport surface along the transport direction of the recording medium, and a pressing member positioned opposite the transport surface of the transport member and capable of pressing the recording medium against the transport surface, wherein a method for attaching the recording medium to the transport surface includes a first step of moving the pressing member upstream in the transport direction from a state in which the recording medium is pressed against the transport surface by the pressing member at a predetermined position in the transport direction.

24. The adhesion method according to claim 23, wherein the first step is performed with the drive of the transport member stopped.

25. An adhesion method according to claim 23 or 24, further comprising: a second step of driving the conveying member to move the conveying surface of the conveying member from the upstream side to the downstream side in the conveying direction; and a third step of moving the pressing member from the upstream side to the downstream side in the conveying direction.

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