Conveying device

Abstract

A simple configuration corrects the belt misalignment. [Solution] The system includes a transport belt 11 located below the head holder 27 that transports paper by endless movement driven by a plurality of transport rollers, a displacement sensor 6 that detects the shift of the transport belt 11, a driven roller 51 that is rotatably mounted above the transport roller 13 located on the upstream side of the plurality of transport rollers, a stopper mechanism 5 that adjusts the gap between the head holder 27 and the plastic template 17 that supports the transport surface of the transport belt 11 from below, and a control unit 7 that, when a shift of the transport belt 11 is detected, causes the stopper mechanism 5 to adjust the gap on the side opposite to the side where the shift was detected in the rotation axis direction of the driven roller 51 to reduce the gap.

Description

Technical Field

[0001] The present invention relates to a conveying device for correcting the deviation of a belt for conveying paper.

Background Art

[0002] For example, an image forming apparatus is provided with a conveying device using a photosensitive belt or an intermediate transfer belt made of an endless belt as a photosensitive member or an intermediate transfer member.

[0003] In such a conveying device, when the belt deviates to one side in the direction of the support shaft, the image position transferred to the transfer paper may shift, vary, or be distorted.

[0004] Patent Document 1 discloses a technique for suppressing belt deviation by moving a rotating arm up and down with a pressurizing motor and adjusting the contact forces on the left and right sides of the secondary transfer roller and the secondary transfer roller shaft.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the technique described in Patent Document 1, since it is necessary to provide the pressurizing motor outside the belt, in the case of a belt platen where the position of the belt conveying roller is fixed in a narrow space, there is no space to provide the pressurizing motor, and there is also a problem that providing the pressurizing motor leads to an increase in manufacturing cost.

[0007] The present invention has been made in view of such problems, and an object thereof is to provide a conveying device for correcting belt deviation with a simple configuration.

Means for Solving the Problems

[0008] To achieve the above objective, the features of the conveying device according to the present invention are: A belt is located below the head holder, stretched across multiple transport rollers, and transports paper by moving endlessly through the drive of the multiple transport rollers, A detection means for detecting the deviation of the belt, A driven roller is rotatably mounted above the upstream conveying roller among the plurality of conveying rollers, A gap adjustment means for adjusting the gap between the head holder and the plastic template that supports the conveying surface of the belt from below, The system also includes a control means that, when the detection means detects a deviation in the belt, causes the gap adjustment means to adjust the gap on the side opposite to the side in the rotation axis direction of the driven roller to reduce the deviation. [Effects of the Invention]

[0009] According to the features of the conveying device of the present invention, the deviation of the belt that conveys the paper can be corrected. [Brief explanation of the drawing]

[0010] [Figure 1] This is a schematic diagram of an inkjet printing apparatus to which a transport device according to an embodiment of the present invention is applied. [Figure 2] Figure 1 is a perspective view showing the schematic configuration of the printing section of the inkjet printing apparatus. [Figure 3] Figure 1 is a perspective view showing the schematic configuration of the stopper mechanism of the inkjet printing apparatus. [Figure 4] Figure 1 is a side view of the inkjet printing apparatus as seen from the right. [Figure 5](a) is a diagram illustrating the height adjustment when a displacement sensor detects a forward shift of the conveyor belt in an inkjet printing apparatus according to an embodiment of the present invention, and (b) is a diagram illustrating the height adjustment when a displacement sensor detects a backward shift of the conveyor belt in an inkjet printing apparatus according to an embodiment of the present invention. [Figure 6] This is a flowchart illustrating the processing steps in an inkjet printing apparatus according to an embodiment of the present invention. [Figure 7] Figure 6 shows a flowchart illustrating the processing steps in an inkjet printing apparatus according to an embodiment of the present invention, specifically the flowchart showing the processing steps in step S105. [Figure 8] Figure 6 shows a flowchart illustrating the processing steps in an inkjet printing apparatus according to an embodiment of the present invention, specifically the flowchart showing the processing steps in step S111. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, identical or equivalent parts and components are denoted by the same or equivalent reference numerals. However, it should be noted that the drawings are schematic and may differ from reality. Furthermore, there are parts where the dimensional relationships and proportions differ between drawings.

[0012] Furthermore, the embodiments shown below are illustrative examples of devices and the like for realizing the technical concept of this invention, and the technical concept of this invention is not limited to the arrangement of each component as described below. The technical concept of this invention can be modified in various ways within the scope of the claims.

[0013] FIG. 1 is a schematic configuration diagram of an inkjet printing apparatus to which a conveying device according to an embodiment of the present invention is applied. FIG. 2 is a perspective view showing a schematic configuration of a printing unit of the inkjet printing apparatus shown in FIG. 1. FIG. 3 is a perspective view showing a schematic configuration of a stopper mechanism unit of the inkjet printing apparatus shown in FIG. 1. FIG. 4 is a side view of the inkjet printing apparatus shown in FIG. 1 as viewed from the right direction. In the following description, the direction orthogonal to the plane of FIG. 1 is defined as the front-rear direction. Also, the up, down, left, and right directions on the plane of FIG. 1 are defined as the up-down and left-right directions, respectively.

[0014] As shown in FIG. 1, an inkjet printing apparatus 1 according to the present embodiment includes a conveying unit 2, a printing unit 3, a lifting mechanism unit 4, four stopper mechanism units 5, a displacement sensor 6, and a control unit 7.

[0015] The conveying unit 2 conveys a sheet P, which is a printing medium fed from a paper feeding unit (not shown). The conveying unit 2 is disposed below the printing unit 3. The conveying unit 2 includes a conveying belt 11, a driving roller 12, driven rollers 13 to 15, a platen 16, a platen plate 17, and a suction unit 18.

[0016] The conveying belt 11 adsorbs and holds the sheet P conveyed by the paper feeding unit and conveys it. The conveying belt 11 is an endless belt wound around the driving roller 12 and the driven rollers 13 to 15. A number of belt holes (not shown), which are through holes for air suction, are formed in the conveying belt 11. The conveying belt 11 adsorbs and holds the sheet P on the conveying surface 11a by the suction force generated in the belt holes due to the driving of a fan 22 of the suction unit 18 described later. The conveying surface 11a is the surface on which the sheet P is placed on the conveying belt 11 and is the upper surface of the planar portion of the conveying belt 11 between the driving roller 12 and the driven roller 13. The conveying belt 11 rotates (moves endlessly) in the clockwise direction in FIG. 1 to convey the adsorbed and held sheet P in the conveying direction from left to right.

[0017] The driving roller 12 rotates the conveying belt 11. The driving roller 12 is rotationally driven by a motor (not shown).

[0018] The driven rollers 13 to 15 support the conveyor belt 11 together with the drive roller 12. The driven rollers 13 to 15 rotate in a driven manner along with the conveyor belt 11. The driven roller 13 is at the same height as the drive roller 12 and is arranged to the left of the drive roller 12. The driven rollers 14 and 15 are arranged at the same height, spaced apart from each other in the left-right direction, below the drive roller 12 and the driven roller 13.

[0019] The platen 16 is a flat plate-like member that is arranged on the lower side of the conveyor belt 11 between the drive roller 12 and the driven roller 13 and supports the conveyor belt 11 slidably. The platen 16 is formed in a rectangular shape in plan view. A plurality of through-holes are formed in the platen 16 for allowing the air sucked by the fan 22 to pass through.

[0020] The platen plate 17 is a flat plate-like member that is arranged below the platen 16 and supports the platen 16 via a plurality of spacers not shown. The platen plate 17 is formed in a rectangular shape in plan view. A plurality of through-holes are formed in the platen plate 17 for allowing the air sucked by the fan 22 to pass through. The upper surface of the platen plate 17 is an abutting surface 17a against which the tip (lower end) of the abutting shaft 45 of the abutting mechanism portion 5 described later abuts. The platen plate 17 is formed larger than the conveyor belt 11 and the platen 16 in the front-rear direction.

[0021] The suction portion 18 sucks air through the through-holes of the platen plate 17, the through-holes of the platen 16, and the belt holes of the conveyor belt 11 to adsorb the sheet P to the conveyor belt 11. The suction portion 18 includes a chamber 21 and a fan 22.

[0022] The chamber 21 forms a negative pressure chamber for generating an adsorbing force in the belt holes of the conveyor belt 11. The chamber 21 is provided on the back side of the platen plate 17.

[0023] Fan 22 exhausts air from chamber 21. As a result, fan 22 draws air through the through holes in the plastic template 17, the platen 16, and the belt holes in the conveyor belt 11, generating suction force at the belt holes and causing the paper P to adhere to the conveyor belt 11.

[0024] The printing unit 3 prints on the paper P transported by the transport unit 2. The printing unit 3 is equipped with multiple inkjet heads 26 and a head holder 27.

[0025] The inkjet head 26 ejects ink onto the paper P. The inkjet head 26 has a plurality of nozzles (not shown) that open on the nozzle surface 26a, which is the lower surface facing the transport surface 11a of the transport belt 11, and ejects ink from the nozzles.

[0026] The head holder 27 holds the inkjet head 26. The head holder 27 holds the inkjet head 26 by allowing its lower end to protrude downward from its lower surface 27a. The head holder 27 is formed in a rectangular shape when viewed from above.

[0027] The lifting mechanism 4 raises and lowers the conveying section 2. The lifting mechanism 4 includes a wire 31 and a winding mechanism 32.

[0028] The wire 31 suspends and supports the conveying section 2. The wire 31 is inserted through a through hole formed in the abutment shaft 45 of each abutment mechanism 5, and its tip (lower end) is connected to the plastic template 17.

[0029] The winding mechanism 32 raises and lowers the conveying unit 2 by winding and unwinding the wire 31.

[0030] The stop mechanism 5 defines the head transport surface distance H shown in Figure 4. The head transport surface distance H is the distance between the head holder 27 and the plastic template 17.

[0031] The driven roller 51 is rotatably mounted above the driven roller 13, which is located on the upstream (left) side of the multiple conveying rollers, and the driven roller 51 and the driven roller 13 sandwich the conveying belt 11 from above and below.

[0032] As shown in Figure 2, the stopper mechanism 5 is located one at each of the four corners of the head holder 27.

[0033] As shown in Figure 3, the abutment mechanism 5 comprises an abutment motor 41, a worm 42, an intermediate gear 43, an abutment gear 44, an abutment shaft 45, a nut 46, and a reference block 47.

[0034] The abutment motor 41 rotates the abutment shaft 45 via a worm gear 42, an intermediate gear 43, and an abutment gear 44, thereby changing the height position of the abutment shaft 45. Forward rotation of the abutment motor 41 lowers the abutment shaft 45, and reverse rotation raises the abutment shaft 45. The abutment motor 41 consists of a pulse motor.

[0035] The worm gear 42 transmits the driving force of the stop motor 41 to the intermediate gear 43. The worm gear 42 is fixed to the output shaft of the stop motor 41.

[0036] The intermediate gear 43 transmits the driving force of the abutment motor 41 from the worm 42 to the abutment gear 44. The intermediate gear 43 is composed of a two-stage gear consisting of a worm wheel 48 that meshes with the worm 42 and a lower gear 49 which is a spur gear that meshes with the abutment gear 44.

[0037] The abutment gear 44 rotates together with the abutment shaft 45 due to the driving force of the abutment motor 41 transmitted from the intermediate gear 43. The abutment gear 44 is integrally formed with the abutment shaft 45 so as to surround the upper end of the abutment shaft 45. The abutment gear 44 consists of a spur gear that meshes with the lower gear 49.

[0038] The abutment shaft 45 is a component whose lower end abuts against the conveying section 2. Specifically, the lower end of the abutment shaft 45 abuts against the abutment surface 17a of the plastic template 17. The abutment shaft 45 is formed by a screw and screwed into a nut 46. This changes the height position of the abutment shaft 45, which rotates when driven by the abutment motor 41. As a result, the distance H between the head conveying surfaces can be changed when the lower end of the abutment shaft 45 abuts against the conveying section 2.

[0039] The abutment shaft 45 has a through hole formed in its axial direction, through which the wire 31 is inserted.

[0040] The height position of the abutment shaft 45 of each abutment mechanism 5 can be individually adjusted steplessly by driving each abutment motor 41. Here, the abutment shaft 45 moves up and down by an amount of movement corresponding to the number of drive pulses of the abutment motor 41, but the amount of movement of the abutment shaft 45 for one drive pulse is small enough that the height position of the abutment shaft 45 can be considered to be continuously adjustable.

[0041] As shown in Figure 2, of the four abutment shafts 45 located at the four corners of the head holder 27, the two abutment shafts 45 located at the front are denoted as abutment shaft 45b, and the two abutment shafts 45 located at the rear are denoted as abutment shaft 45a.

[0042] The nut 46 is used to change the height position of the rotating abutment shaft 45. The nut 46 is fixed to the lower surface 27a of the head holder 27.

[0043] The reference block 47 defines the reference height position of the abutment shaft 45. The abutment shaft 45 is positioned at the reference height position when its upper end abuts against the reference block 47 and stops.

[0044] The displacement sensor 6 is positioned on the lower surface 27a of the head holder 27. The displacement sensor 6 consists of a Contact Image Sensor (CIS), which is a line sensor larger than the conveyor belt 11 in the front-rear direction. Light emitted downward is reflected by the conveyor belt 11 and received by the CIS. Based on the reflected light, the position of the conveyor belt 11, i.e., whether the conveyor belt 11 is moving forward or backward, is detected.

[0045] The control unit 7 controls the operation of each part of the inkjet printing device 1. The control unit 7 is composed of a CPU, RAM, ROM, hard disk, etc.

[0046] When the displacement sensor 6 detects a shift in the conveyor belt 11, the control unit 7 adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 to reduce the distance H (gap) between the head conveying surfaces on the opposite side of the side where the shift in the rotation axis direction (front-rear direction) of the driven roller 51 is detected. In other words, when the displacement sensor 6 detects a shift in the forward direction of the conveyor belt 11, the control unit 7 adjusts the height position of the abutment shaft 45a of each abutment mechanism 5 to reduce the distance H (gap) between the rear head conveying surfaces. On the other hand, when the displacement sensor 6 detects a shift in the rear direction of the conveyor belt 11, the control unit 7 adjusts the height position of the abutment shaft 45b of each abutment mechanism 5 to reduce the distance H (gap) between the front head conveying surfaces.

[0047] The operation of adjusting the distance H between the head transport surfaces in the inkjet printing apparatus 1 will be explained with reference to Figure 5.

[0048] Figure 5(a) illustrates the height adjustment in an inkjet printing apparatus according to an embodiment of the present invention when the displacement sensor 6 detects a forward shift of the conveyor belt 11, and Figure 5(b) illustrates the height adjustment in an inkjet printing apparatus according to an embodiment of the present invention when the displacement sensor 6 detects a backward shift of the conveyor belt 11.

[0049] When the displacement sensor 6 detects a forward shift of the conveyor belt 11, as shown in Figure 5(a), the control unit 7 adjusts the height position of the abutment shaft 45a of each abutment mechanism 5 to reduce the distance H (gap) between the head conveying surfaces on the opposite side of the side where the shift in the rotation axis direction of the driven roller 51 was detected, i.e., the rear side. Here, the control unit 7 adjusts the height of the rear abutment shaft 45a so that the distance H between the rear head conveying surfaces is distance h1, and adjusts the height of the front abutment shaft 45b so that the distance H between the front head conveying surfaces is longer than distance h1, i.e., distance h2. Since distance h2 is the same distance as the distance H (gap) between the head conveying surfaces during printing, it is also possible to adjust only the height of the rear abutment shaft 45a.

[0050] As a result, the contact force between the driven roller 51 and the conveyor belt 11 increases at the rear, causing the conveyor belt 11, which was previously positioned towards the front, to move towards the rear.

[0051] When the tension of the conveyor belt 11 is uniform on both the front and rear sides, the conveyor belt 11 rotates (moves endlessly) in the clockwise direction as shown in Figure 1 without any twisting in either the forward or backward direction.

[0052] However, the conveyor belt 11 will curve in the direction of less tension. For example, if the tension at the rear is greater than the tension at the front, the conveyor belt 11 will curve forward. In order to move the conveyor belt 11 to the rear and eliminate this curve, the tension at the front must be greater than the tension at the rear.

[0053] Therefore, in order to make the tension on the front side greater than the tension on the rear side, the contact force on the rear side is increased. When the contact force on the rear side is increased, the frictional force on the rear side increases, and when the frictional force on the rear side increases, the tension on the rear side decreases. In other words, the tension on the front side becomes greater than that on the rear side, and the conveyor belt 11 moves to the rear side.

[0054] On the other hand, when the displacement sensor 6 detects that the conveyor belt 11 is shifting backward, the control unit 7 adjusts the height position of the abutment shaft 45b of each abutment mechanism 5 to reduce the distance H (gap) between the front head conveying surfaces. Here, the control unit 7 adjusts the height of the front abutment shaft 45b so that the distance H between the front head conveying surfaces is distance h1, and adjusts the height of the rear abutment shaft 45a so that the distance H between the rear head conveying surfaces is longer than distance h1, to distance h2.

[0055] As a result, the contact force between the driven roller 51 and the conveyor belt 11 increases at the front, causing the conveyor belt 11, which was previously positioned towards the rear, to move towards the front.

[0056] Figure 6 is a flowchart showing the processing steps in an inkjet printing apparatus 1 according to an embodiment of the present invention.

[0057] In step S101, the control unit 7 determines whether or not the inkjet printing device 1 is printing.

[0058] If it is determined that printing is not in progress (step S101; NO), in step S111, the control unit 7 sets the belt-bias correction normal mode.

[0059] On the other hand, if it is determined that printing is in progress (step S101; YES), in step S103, the control unit 7 temporarily suspends printing on the inkjet printer 1, and in step S105, the control unit 7 sets a belt-biased high-speed mode to minimize the recovery time until printing resumes.

[0060] Here, the normal belt alignment correction mode is a mode in which the belt alignment of the conveyor belt 11 is corrected at a normal speed by moving the conveyor belt 11 endlessly at a first speed. This reduces the deterioration of the driven roller 51. The high-speed belt alignment correction mode is a mode in which the belt alignment correction time is shortened compared to the normal belt alignment correction mode by moving the conveyor belt 11 endlessly at a second speed which is faster than the first speed. This increases the contact force between the conveyor belt 11 and the driven roller 51.

[0061] In step S107, the control unit 7 restarts printing on the inkjet printer 1.

[0062] Figure 7 is a flowchart showing the processing content of step S105 in the flowchart illustrating the processing content of the inkjet printing apparatus 1 according to the embodiment of the present invention shown in Figure 6.

[0063] In step S201, the control unit 7 determines whether the direction of movement is forward based on the detection result of the displacement sensor 6.

[0064] If it is determined that the approach direction is towards the front (step S201; YES), in step S203, the control unit 7 rotates the conveyor belt 11 at a second speed faster than the first speed, and adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the rear head conveyor surfaces becomes distance h1.

[0065] On the other hand, if it is determined that the approach direction is towards the rear (step S201; NO), in step S205, the control unit 7 rotates the conveyor belt 11 at a second speed faster than the first speed, and adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the front head conveyor surfaces becomes distance h1.

[0066] In step S207, the control unit 7 determines whether the position of the conveyor belt 11 has returned to neutral, that is, whether the misalignment has been resolved.

[0067] If it is determined that the position of the conveyor belt 11 has returned to neutral (step S207; YES), in step S209, the control unit 7 adjusts the distance H (gap) between the head conveyor surfaces to its original height, that is, the distance h2 between the height position of the front abutment shaft 45 and the height position of the rear abutment shaft 45.

[0068] Figure 8 is a flowchart showing the processing content of step S111 in the flowchart illustrating the processing content of the inkjet printing apparatus 1 according to the embodiment of the present invention shown in Figure 6.

[0069] In step S301, the control unit 7 determines whether the direction of movement is forward based on the detection result of the displacement sensor 6.

[0070] If it is determined that the approach direction is forward (step S301; YES), in step S303, the control unit 7 rotates the conveyor belt 11 at a first speed and adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the rear head conveyor surfaces becomes distance h3.

[0071] On the other hand, if it is determined that the approach direction is towards the rear (step S301; NO), in step S305, the control unit 7 rotates the conveyor belt 11 at a first speed and adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the front head conveyor surfaces becomes distance h3.

[0072] Here, the head transport plane distance H (gap) to be adjusted is given by the relationship shown in (Equation 1) below.

[0073] Distance h2>Distance h3>Distance h1 (Formula 1) Thus, in the normal belt alignment correction mode, when the displacement sensor 6 detects an alignment of the conveyor belt 11, the control unit 7 adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the head conveyor surfaces on the opposite side of the side where the alignment is detected in the rotation axis direction (front-rear direction) of the driven roller 51 becomes distance h3. Therefore, since the contact force is smaller compared to the high-speed belt alignment correction mode, the alignment of the conveyor belt 11 can be corrected while reducing deterioration of the driven roller 51.

[0074] On the other hand, in the high-speed belt alignment correction mode, when the displacement sensor 6 detects an alignment of the conveyor belt 11, the control unit 7 adjusts the height position of the abutment shaft 45 of each abutment mechanism 5 so that the distance H (gap) between the head conveyor surfaces on the opposite side of the side where the alignment is detected in the rotation axis direction (front-rear direction) of the driven roller 51 becomes distance h1. Therefore, since the contact force is greater compared to the normal belt alignment correction mode, the belt alignment correction time can be shortened.

[0075] In step S307, the control unit 7 determines whether the position of the conveyor belt 11 has returned to neutral, that is, whether the misalignment has been resolved.

[0076] If it is determined that the position of the conveyor belt 11 has returned to neutral (step S307; YES), in step S309, the control unit 7 adjusts the distance H (gap) between the head conveyor surfaces to its original height, that is, the distance h2 between the height position of the front abutment shaft 45 and the height position of the rear abutment shaft 45.

[0077] (Note) This application discloses the following invention:

[0078] (Note 1) A belt is located below the head holder, stretched across multiple transport rollers, and transports paper by moving endlessly through the drive of the multiple transport rollers, A detection means for detecting the deviation of the belt, A driven roller is rotatably mounted above the upstream conveying roller among the plurality of conveying rollers, A gap adjustment means for adjusting the gap between the head holder and the plastic template that supports the conveying surface of the belt from below, When the detection means detects a deviation in the belt, the control means causes the gap adjustment means to adjust the gap on the side opposite to the side where the deviation was detected in the rotation axis direction of the driven roller to reduce the gap, A conveying device characterized by being equipped with the following features.

[0079] As a result, the gap on the side opposite to the side where the deviation in the rotation axis direction of the driven roller is detected becomes smaller, increasing the contact force between the driven roller and the belt. This causes the deviationed belt to move to the opposite side and return to the neutral position. Therefore, the deviation of the belt can be corrected with a simple configuration without having to install a new device for correcting the belt deviation on the outside of the belt.

[0080] (Note 2) The gap adjustment means is The gap is adjusted by adjusting the height of the abutment shaft, which is provided between the inkjet head holder and the plastic template, near both ends of the belt in the rotation axis direction of the driven roller, and whose lower end abuts against the plastic template. The conveying device described in (Appendix 1), characterized by the above.

[0081] This allows the gap to be adjusted by adjusting the height of the abutment shaft, enabling reliable gap adjustment with a simple configuration.

[0082] (Note 3) The device includes a lifting mechanism for raising and lowering the aforementioned belt, The control means is The lifting means controls the gap to be adjusted by the gap adjustment means. The conveying device described in (Appendix 1), characterized by the above.

[0083] This allows the gap to be adjusted to the gap adjusted by the gap adjustment mechanism by raising the lifting mechanism, thus enabling reliable gap adjustment with a simple configuration.

[0084] (Note 4) The control means is The gap adjustment means is configured to adjust the gap when the belt is moving endlessly at a first speed to be larger than the gap when it is moving endlessly at a second speed which is faster than the first speed. The conveying device described in (Appendix 1), characterized by the above.

[0085] This allows switching between a first speed setting, where the wear of the driven rollers is reduced while correcting the belt misalignment, and a second speed setting, where the belt misalignment correction time is shortened. [Explanation of Symbols]

[0086] 1. Inkjet printing device 2. Conveying section 3 Printing Department 4. Lifting mechanism 5. Buttock mechanism (gap adjustment means) 6. Displacement Sensor 7 Control Unit 11. Conveyor belt 11a Conveying surface 12 drive rollers 13 Conveyor rollers 13-15 Driven rollers 16 Platen 17 Plastic Templates 17a Immediately 18 Suction part 21 Chambers 22 Fans 26 inkjet heads 27 Head holder 31 wires 32 Winding mechanism section 41. Push motor 42 Warm 43 Intermediate gear 44 Charge Gear 45, 45a, 45b Axle 46 nuts 47 Reference Blocks 48 Worm Wheel 49 Lower gear 51 Driven roller

Claims

1. A belt is located below the head holder, stretched across multiple transport rollers, and transports paper by moving endlessly through the drive of the multiple transport rollers, A detection means for detecting the deviation of the belt, A driven roller is rotatably mounted above the upstream conveying roller among the plurality of conveying rollers, A gap adjustment means for adjusting the gap between the head holder and the plastic template that supports the conveying surface of the belt from below, When the detection means detects a deviation in the belt, the control means causes the gap adjustment means to adjust the gap on the side opposite to the side where the deviation was detected in the rotation axis direction of the driven roller to reduce the gap, A conveying device characterized by being equipped with the following features.

2. The gap adjustment means is The gap is adjusted by adjusting the height of the abutment shaft, which is provided between the head holder and the plastic template, near both ends of the belt in the rotation axis direction of the driven roller, and whose lower end abuts against the plastic template. The conveying device according to claim 1.

3. The device includes a lifting mechanism for raising and lowering the aforementioned belt, The control means is The lifting means controls the gap to be adjusted by the gap adjustment means. The conveying device according to claim 1.

4. The control means is The gap adjustment means is configured to adjust the gap when the belt is moving endlessly at a first speed to be larger than the gap when it is moving endlessly at a second speed which is faster than the first speed. The conveying device according to claim 1.

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