Conveying device

Abstract

To provide a carrier device capable of lessening separation and scattering of dust from a static elimination brush.SOLUTION: A conveyor belt 21 conveys a sheet P while rotating. A static elimination brush 6 electrostatically discharges the sheet P conveyed by the conveyor belt 21. A control part 8 performs, when a conveyance part 3 is moved from a jam release position to a conveyance position, control so that the conveyor belt 21 abuts on the static elimination brush 6 while rotating in the same direction with the conveyance of the sheet P.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a conveying device.

Background Art

[0002] There is known a printing apparatus that sucks and conveys a sheet on a charged conveyance belt and ejects ink from an inkjet head to print on the sheet.

[0003] Also, in such a printing apparatus, it is known to provide a static elimination brush for eliminating static electricity from the printing surface of the sheet in order to ensure the attracting force of the conveying unit (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the printing apparatus as described above, when a paper jam occurs, the conveying unit is lowered from the conveying position, which is the position where paper conveyance is performed, to the jam release position, which is the position for performing jam release work. Here, in a state where the conveying unit is arranged at the conveying position, the static elimination brush has its bristles in contact with the conveyance belt. In a state where the conveying unit is arranged at the jam release position, the static elimination brush is separated from the conveyance belt.

[0006] When the conveyance unit ascends from the jam release position to the conveyance position after jam release and the static elimination brush contacts the conveyance belt, the static elimination brush is pushed by the conveyance belt and the posture of the static elimination brush varies. If the paper conveyance operation is started as it is and the conveyance belt is rotated vigorously, the posture of the static elimination brush changes abruptly, so that dust such as paper powder accumulated on the static elimination brush is likely to separate from and scatter from the static elimination brush. If the dust that has separated from and scattered from the static elimination brush adheres to the nozzle surface of the inkjet head, the print image quality deteriorates.

[0007] The present invention has been made in view of the above circumstances, and an object thereof is to provide a conveyance device capable of reducing the separation and scattering of dust from the static elimination brush.

Means for Solving the Problems

[0008] In order to achieve the above object, a conveyance device according to the present invention includes a conveyance mechanism that conveys an object to be conveyed while rotating, a static elimination brush that eliminates static electricity of the object to be conveyed conveyed by the conveyance mechanism, and the conveyance mechanism and the static elimination brush. When shifting from a state where they are separated to a state where the static elimination brush contacts the conveyance mechanism in order to eliminate static electricity of the object to be conveyed, the conveyance mechanism rotates in the same direction as when conveying the object to be conveyed and controls so as to contact the static elimination brush. It is characterized by having a control unit.

Effects of the Invention

[0009] According to the conveyance device of the present invention, it is possible to reduce the separation and scattering of dust from the static elimination brush.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and components are denoted by the same or equivalent reference numerals throughout the drawings.

[0012] The embodiments shown below illustrate devices and the like for embodying the technical idea of this invention. The technical idea of this invention does not specify the materials, shapes, structures, arrangements, etc. of each component part as the following. The technical idea of this invention can be variously modified within the scope of the claims.

[0013] FIG. 1 is a schematic configuration diagram of a printing apparatus provided with a conveying apparatus according to an embodiment of the present invention. FIG. 2 is a control block diagram of the printing apparatus shown in FIG. 1. 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-right directions in the plane of FIG. 1 are defined as the up-down, left-right directions. In FIG. 1, the direction from left to right is the conveying direction of the sheet P (corresponding to the object to be conveyed), which is the printing medium. In the following description, upstream and downstream refer to upstream and downstream in the conveying direction of the sheet P.

[0014] As shown in FIGS. 1 and 2, the printing apparatus 1 according to the present embodiment includes a sheet feeding unit 2, a conveying unit 3, a lifting drive unit 4, a pressing roller 5, a static eliminator brush 6, a printing unit 7, and a control unit 8.

[0015] The sheet feeding unit 2 feeds the sheet P to the conveying unit 3. The sheet feeding unit 2 includes a sheet feeding table 11, a sheet feeding roller 12, and a registration roller 13.

[0016] The sheet feeding table 11 is for stacking the sheet P used for printing.

[0017] The paper feed roller 12 picks up and conveys the sheets P one by one from the paper feed tray 11, and abuts and stops the sheet P against the registration roller 13. The paper feed roller 12 is driven by a motor (not shown).

[0018] The registration roller 13 temporarily stops the sheet P conveyed by the paper feed roller 12 and then conveys it toward the conveying unit 3. The registration roller 13 is driven by a motor (not shown).

[0019] The conveying unit 3 conveys the sheet P conveyed by the registration roller 13 while adsorbing and holding it by electrostatic adsorption.

[0020] The conveying unit 3 is movable between a conveying position and a jam release position by an elevating drive unit 4. The conveying position of the conveying unit 3 is the position of the conveying unit 3 when conveying the sheet P to be printed. The conveying position of the conveying unit 3 is the position of the conveying unit 3 shown in FIG. 1 and the position of the conveying unit 3 shown by the two-dot chain line in FIG. 3, and is near the lower side of the printing unit 7. The jam release position of the conveying unit 3 is the position of the conveying unit 3 when the user removes the sheet P remaining in the printing apparatus 1 by the jam release operation. The jam release position of the conveying unit 3 is the position of the conveying unit 3 shown by the solid line in FIG. 3 and is below the conveying position.

[0021] The conveying unit 3 includes a conveying belt (corresponding to a conveying mechanism) 21, a pair of support rollers 22A and 22B, a tension roller 23, a tension applying spring 24, a conveying motor 25, a charging roller 26, a charging power source 27, and a cleaning blade 28.

[0022] The conveying belt 21 sucks and holds the sheet P and conveys it. The conveying belt 21 is an endless belt stretched between the support rollers 22A and 22B. The conveying belt 21 sucks and holds the sheet P on the conveying surface 21a by the electrostatic adsorption force generated by being charged by the charging roller 26. The conveying surface 21a is the upper surface of the conveying belt 21 stretched between the support rollers 22A and 22B, and is formed in a horizontal plane. During printing, the conveying belt 21 rotates (moves endlessly) in the clockwise direction in FIG. 1, and conveys the sheet P sucked and held on the conveying surface 21a to the right.

[0023] The support rollers 22A and 22B support the conveying belt 21. The support rollers 22A and 22B are arranged at the same height with a distance from each other in the left - right direction. The support roller 22A is rotationally driven by the conveying motor 25 to rotate the conveying belt 21. The support roller 22B rotates in a driven manner following the rotating conveying belt 21. It should be noted that the support roller 22B may be rotationally driven by the conveying motor 25, and the support roller 22A may rotate in a driven manner following the conveying belt 21.

[0024] The tension roller 23 is a member that applies tension to the conveying belt 21. By applying tension to the conveying belt 21 by the tension roller 23, a planar conveying surface 21a is formed between the support rollers 22A and 22B. The tension roller 23 rotates in a driven manner following the rotating conveying belt 21. The tension roller 23 is arranged at a position lower than the support rollers 22A and 22B between the support rollers 22A and 22B.

[0025] The tension - applying spring 24 applies tension to the conveying belt 21 via the tension roller 23 by pressing down the tension roller 23.

[0026] The conveying motor 25 rotationally drives the support roller 22A. It should be noted that the conveying motor 25 may be configured to rotationally drive the support roller 22B.

[0027] The charging roller 26 charges the conveyor belt 21 by applying an electric charge to the conveyor belt 21. The charging roller 26 is disposed at a position in contact with the conveyor belt 21 and rotates in a driven manner with the conveyor belt 21.

[0028] The charging power source 27 applies a voltage for charging the conveyor belt 21 to the charging roller 26.

[0029] The cleaning blade 28 cleans the conveyor belt 21.

[0030] The elevating drive unit 4 elevates and lowers the conveyance unit 3 between the conveyance position and the jam release position. The elevating drive unit 4 includes a motor or the like.

[0031] The pressing roller 5 is a roller that presses the sheet P against the conveyor belt 21. The pressing roller 5 is disposed at a position where it contacts the conveyor belt 21 above the support roller 22B when the conveyance unit 3 is disposed at the conveyance position. The pressing roller 5 rotates in a driven manner with the conveyor belt 21. The pressing roller 5 does not lower even when the conveyance unit 3 descends from the conveyance position. For this reason, in a state where the conveyance unit 3 is disposed at the jam release position, the pressing roller 5 and the conveyor belt 21 are separated from each other.

[0032] The static elimination brush 6 eliminates static electricity from the sheet P conveyed by the conveyor belt 21. The static elimination brush 6 is disposed on the upstream side of the printing unit 7. When the conveyance unit 3 is disposed at the conveyance position, the tips of the bristles of the static elimination brush 6 are in contact with the conveyor belt 21. When the conveyance unit 3 is disposed at the jam release position, the static elimination brush 6 and the conveyor belt are separated from each other.

[0033] The printing unit 7 ejects ink onto the sheet P conveyed by the conveyance unit 3 to print an image. The printing unit 7 includes a plurality of inkjet heads 31.

[0034] The inkjet head 31 has a plurality of nozzles arranged along the front-rear direction, and ejects ink from the nozzles. The nozzles open to the nozzle surface 31a which is the lower surface of the inkjet head 31. The plurality of inkjet heads 31 are arranged in parallel along the conveyance direction (left-right direction) of the paper P.

[0035] The control unit 8 controls the operations of each part of the printing apparatus 1. The control unit 8 is configured to include a CPU, a RAM, a ROM, a hard disk, etc.

[0036] When the control unit 8 moves the conveyance unit 3 from the jam release position to the conveyance position after jam release, it controls so that the conveyance belt 21 rotates (runs endlessly) in the same direction as when conveying the paper P and contacts the static eliminator brush 6.

[0037] Next, the operation of the printing apparatus 1 will be described.

[0038] When performing printing, the paper feed roller 12 sequentially picks up the paper P from the paper feed tray 11 and sends it out to the registration roller 13. The paper P picked up from the paper feed tray 11 is abutted against the registration roller 13 and temporarily stopped, and then conveyed to the conveyance unit 3 by the registration roller 13. The paper P that has reached the conveyance surface 21a of the conveyance belt 21 of the conveyance unit 3 is pressed against the conveyance belt 21 by the pressing roller 5, and is conveyed while being adsorbed on the conveyance surface 21a by the electrostatic force in the conveyance belt 21 charged by the charging roller 26.

[0039] At this time, on the upstream side of the inkjet head 31, the printing surface of the paper P is discharged by the static eliminator brush 6. After passing through the static eliminator brush 6, the paper P is printed with the ink ejected from the inkjet head 31. Here, the conveyance unit 3 is arranged at the conveyance position and conveys the paper P at a predetermined printing conveyance speed.

[0040] The printed paper P is conveyed by a conveyance roller (not shown) on the downstream side of the conveyance unit 3 and sequentially discharged to a paper discharge tray (not shown).

[0041] If a jam occurs in the paper P during the printing operation as described above, the control unit 8 stops the paper feeding unit 2 and the conveying unit 3. Next, the control unit 8 moves (descends) the conveying unit 3 from the conveying position to the jam release position. After that, the user performs a jam release operation to remove the paper P remaining in the printing apparatus 1.

[0042] After the jam is released, the control unit 8 moves (ascends) the conveying unit 3 from the jam release position to the conveying position while rotating the conveying belt 21. As a result, the conveying belt 21 comes into contact with the static elimination brush 6 while rotating (endlessly moving). At this time, the control unit 8 controls so that the conveying belt 21 rotates in the same direction as when the paper P is conveyed and comes into contact with the static elimination brush 6 at a lower speed than when the paper P is conveyed.

[0043] As a result, since the static elimination brush 6 is pushed against the conveying belt 21 while receiving a downstream direction force, when the conveying unit 3 is disposed at the conveying position, as shown in FIG. 4, the static elimination brush 6 has a posture in which the brush tips are aligned facing downstream.

[0044] After the conveying unit 3 has completely moved from the jam release position to the conveying position, the control unit 8 stops the rotation of the conveying belt 21. After that, when restarting the printing operation, the control unit 8 controls so that the conveying belt 21 rotates at the rotation speed when the paper P is conveyed.

[0045] Here, different from the present embodiment, when the conveying unit 3 is moved from the jam release position to the conveying position with the conveying belt 21 stopped, when the static elimination brush 6 comes into contact with the conveying belt 21, the static elimination brush 6 is pushed by the conveying belt 21, and as shown in FIG. 5, the posture of the static elimination brush 6 varies.

[0046] In this state, when the rotation of the conveying belt 21 is started to resume the printing operation, since the posture of the static elimination brush 6 suddenly changes, as shown in FIG. 6, a phenomenon in which dust 41 such as paper powder accumulated on the static elimination brush 6 separates and scatters from the static elimination brush 6 easily occurs. When the dust 41 separated and scattered from the static elimination brush 6 adheres to the nozzle surface 31a of the inkjet head 31, it causes a deterioration in the printing image quality.

[0047] In contrast, in the present embodiment, as described above, when the conveying unit 3 is disposed at the conveying position, the static eliminator brush 6 is in a posture in which the tips of the bristles are aligned and directed downstream. Therefore, even if the rotation of the conveyor belt 21 is started to resume the printing operation, the posture of the static eliminator brush 6 does not change, so that the separation and scattering of dust from the static eliminator brush 6 are reduced.

[0048] As described above, in the printing apparatus 1, when the control unit 8 moves the conveying unit 3 from the jam release position to the conveying position, the control unit 8 controls the conveyor belt 21 to rotate in the same direction as when the paper P is conveyed and come into contact with the static eliminator brush 6. Thereby, when the conveying unit 3 is disposed at the conveying position, the static eliminator brush 6 is in a posture in which the tips of the bristles are aligned and directed downstream. Therefore, even if the rotation of the conveyor belt 21 is started to resume the printing operation, the posture of the static eliminator brush 6 does not change, so that the separation and scattering of dust from the static eliminator brush 6 are reduced.

[0049] In the above-described embodiment, the configuration in which the conveyor belt 21 (conveying unit 3) moves up and down with respect to the fixed static eliminator brush 6 has been described. However, the present invention is not limited to this, and any configuration in which at least one of the static eliminator brush 6 and the conveyor belt 21 moves so that the static eliminator brush 6 and the conveyor belt 21 can be brought into contact with and separated from each other may be used. Further, the conveying mechanism is not limited to the conveyor belt 21 that conveys the paper P, and any mechanism that conveys the object to be conveyed while rotating may be used. When shifting from a state where the conveying mechanism and the static eliminator brush are separated to a state where the static eliminator brush comes into contact with the conveying mechanism in order to perform static elimination of the object to be conveyed, any control may be used as long as the conveying mechanism rotates in the same direction as when the object to be conveyed is conveyed and comes into contact with the static eliminator brush.

[0050] The present invention is not limited to the above-described embodiment as it is, and at the implementation stage, the components can be modified and embodied without departing from the gist thereof. Further, various inventions can be formed by appropriately combining a plurality of components disclosed in the above-described embodiment. For example, some components may be deleted from all the components shown in the embodiment.

[0051] [Supplementary Note] The present application discloses the following invention.

[0052] (Appendix 1) A conveying mechanism that conveys the object to be conveyed while rotating, An electrostatic elimination brush that eliminates static electricity from the object to be conveyed by the conveying mechanism, A control unit that controls the conveying mechanism to rotate in the same direction as when conveying the object to be conveyed and come into contact with the electrostatic elimination brush when shifting the electrostatic elimination brush from a state where it is separated from the conveying mechanism to a state where it comes into contact with the conveying mechanism in order to eliminate static electricity from the object to be conveyed A conveying device characterized by comprising the above.

Explanation of Reference Numerals

[0053] 1 Printing device 2 Paper feeding unit 3 Conveying unit 4 Lifting drive unit 5 Pressing roller 6 Electrostatic elimination brush 7 Printing unit 8 Control unit 21 Conveyor belt 21a Conveying surface 22A, 22B Support rollers 23 Tension roller 24 Tension spring 25 Conveying motor 26 Charging roller 27 Charging power supply 28 Cleaning blade

Claims

1. A conveying mechanism that conveys an object to be conveyed while rotating, An electrostatic elimination brush that eliminates static electricity from the object to be conveyed by the conveying mechanism, A control unit that performs control to shift the conveying mechanism from a state of being separated from the electrostatic elimination brush to a state of contacting the electrostatic elimination brush while the conveyance of the object to be conveyed by the conveying mechanism is stopped, and in this control, controls the conveying mechanism to contact the electrostatic elimination brush while rotating in the same direction as when conveying the object to be conveyed A conveying device, characterized by comprising the above components.

2. A conveying mechanism that conveys an object to be conveyed while rotating, An electrostatic elimination brush that eliminates static electricity from the object to be conveyed by the conveying mechanism, A control unit that controls the conveying mechanism to contact the electrostatic elimination brush while rotating in the same direction as when conveying the object to be conveyed at a lower speed than when conveying the object to be conveyed when shifting the electrostatic elimination brush from a state of being separated from the conveying mechanism to a state of contacting the conveying mechanism for the purpose of eliminating static electricity from the object to be conveyed A conveying device, characterized by comprising the above components.

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