JP2000118819A - Sheet conveyer device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet conveyer device which can convey a sheet with the form projecting upward. SOLUTION: This conveyer device 1 conveys a sheet curved upward which is exhausted from a printing device. To a main body 3, a pair of conveying guides 15 are provided. To an opening 16 between the conveying guides 15, a conveying means 11 is provided. The conveying means 11 can move up and down. At the upper side of the conveying means 11, a sensor 20 is provided. When a sheet 2 enters on a conveying surface 18, the sensor 20 detects the upper surface of the sheet 2. A control means decides the curved amount of a printing paper 2 from the distance of the sheet 2 and the sensor 20, and the distance of the conveying surface 18 and the sensor 20. The control means raises the conveying means 11 according to this curved amount. The belts 13 of the conveying means 11 are contacted to the lower surface of the sheet 12 upper than the conveying surface 18. The printing paper 2 is conveyed by driving the belts 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying apparatus, and more particularly to a sheet conveying apparatus capable of surely conveying a sheet deformed into an upwardly convex shape by a process such as printing.

[0002]

2. Description of the Related Art The applicant of the present invention has proposed, in Japanese Patent Application No. 6-101236, an invention relating to a paper discharge device of a printing press.
This paper ejection device receives the postcard printed by the printing device, dries the ink while transporting it while holding it,
The device is then dropped and stored in a tray. This invention was disclosed in JP-A-7-309496. The present invention will be described with reference to FIGS.

[0003] A sheet conveying device 100 is provided on the discharge port side of a printing device (not shown). The sheet conveying device 100 is connected to a sheet discharging device 101. The printing paper output from the printing apparatus is conveyed to the sheet conveying apparatus 100 and stored in the sheet discharging apparatus 101.

[0004] As shown in FIG.
Has a transport surface 102 for transporting the sheet. At the center of the transfer surface 102, an opening 1 is provided along the transfer direction.
03 is provided. In other words, two plate bodies are arranged at a predetermined interval along a direction orthogonal to the transport direction, and configure the transport surface 102. The opening 103 is provided with a sheet conveying means. The transport means has a pair of pulleys 104 and a belt 105 wrapped around the pulleys. The upper side of the belt 105 that contacts the lower surface of the sheet 106 is within the transport surface 102. The upper side of the belt 105 contacts the lower surface of the sheet 106 on the transport surface 102 to transport the sheet 106.

As shown in FIG. 4, a paper discharging device 101 has a substantially box-shaped frame 110 as a main body. Frame 110
Are placed along the sides of the sheet 106 to be conveyed.
A plurality of shafts 111 are arranged. Each shaft 111 is provided with holding means 112 composed of four blades.

In the frame 110, a pair of upper and lower drive shafts 113 are arranged below the shafts 111, respectively. Each pair of drive shafts 113, 113 has 2
A belt 114 is wound around each book. Each belt 1
14 is provided with a number of paper receiving pieces 115 at predetermined intervals. As shown in FIG. 5, when viewed in a plane orthogonal to the conveying direction of the sheet 106, the interval between the left and right belts 114, 114 is wide at the upper portion and substantially equal to the width of the sheet 106 at the lower portion.

[0007] At the bottom of the frame 110 is a paper discharge tray 11
6 is provided so as to be able to be pulled out.

The sheet 106 is conveyed to the outside after being printed by a printing device (not shown). The printed sheet 106 discharged from the printing apparatus is transferred to the sheet conveying apparatus 1
00 on the transfer surface 102. Belt 105
Moves in contact with the lower surface of the sheet 106, and moves the sheet 106 along the transport surface 102. Sheet 1
06 is held by the holding means 112. With the rotation of the shaft 111, the sheet 106 becomes the paper receiving piece 1 of the lower belt 114.
15 between. The sheet 106 is carried downward by the movement of the belt 114. The ink dries during transport, and the position in the width direction is determined. Thereafter, the sheets 106 fall into the sheet discharge tray 116 and are stacked.

[0009]

As shown in FIG. 7, the sheet 106 is warped to an upwardly convex state when viewed from a cross section orthogonal to the transport direction by being printed on the upper surface side with ink. . Therefore, the central portion of the lower surface of the sheet 106 is above the conveying surface 102. That is, the sheet 106 is in a state separated from the belt 105 of the conveying unit, and the conveyance failure of the sheet 106 has occurred. Specifically, when the sheet 106 is a postcard, the warpage amount is 3 mm.
Above this, it was impossible to carry.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet conveying apparatus capable of conveying a sheet (printing paper) without being affected by warpage.

[0011]

According to a first aspect of the present invention, there is provided a sheet conveying apparatus, comprising: a conveying surface for conveying a sheet (printing paper); In order to convey the sheet by contacting the lower surface, a conveying means (11) is provided such that a portion contacting the lower surface of the sheet is located above the conveying surface.

[0012] Even when a sheet (printing paper 2) having an upwardly convex shape in a cross section orthogonal to the transport direction is placed on the transport surface (18), the upper end of the transport means is located within the transport surface. Is also at the top, so that the conveying means (11) can contact the lower surface of the warped sheet, and can convey the printing paper.

A sheet conveying device (1) according to a second aspect of the present invention includes a conveying surface (18) for conveying a sheet (printing paper 2), and a lower surface of the sheet on the conveying surface. Conveying means (11) for conveying the sheet, and elevating means for elevating the conveying means such that a portion in contact with the lower surface of the sheet moves at least between a position within the conveying surface and a position above the conveying surface. Means (elevation motor 5), detection means (sensor 20) for detecting the position of the sheet to be conveyed, and the conveyance means for detecting the position of the sheet conveyed in the conveyance plane in accordance with the position of the sheet detected by the detection means. Control means (30) for controlling the elevating means so as to move upward from the position.

According to a third aspect of the present invention, there is provided the sheet conveying apparatus according to the second aspect, wherein the detecting means is provided above the conveying surface and the detecting means is provided on the conveying surface. A sensor (20) for detecting and outputting a distance to the upper surface of the sheet, wherein the control means (30)
However, the amount of warpage of the sheet is calculated from the difference between the distance from the sensor to the transport surface and the distance detected by the sensor from the sensor to the upper surface of the sheet.

According to a fourth aspect of the present invention, in the sheet transporting apparatus according to the third aspect, an opening (16) is formed at the center of the transporting surface (18) along the transporting direction of the sheet. ) Is formed, and the transporting means is provided in the opening.

According to a fifth aspect of the present invention, there is provided the sheet transporting apparatus according to the fourth aspect, wherein the transporting means is provided on the support base and the support base. It includes a pair of pulleys (12) and a belt (13) looped around the pair of pulleys, and the upper side of the belt is located within an opening in the transport surface and at a position above it. The lifting means raises and lowers the support table so that the support table can be moved between the support tables.

According to a sixth aspect of the present invention, there is provided the sheet conveying apparatus according to the first or second or third aspect, wherein the sheet (printing paper 2) is upwardly convex in a cross section orthogonal to the conveying direction. The shape is characterized by.

According to a seventh aspect of the present invention, there is provided the sheet conveying apparatus according to the first or second or third aspect, wherein the sheet (printing) having an upward convex shape in a cross section orthogonal to the conveying direction. The present invention is characterized in that it is applied to a sheet processing means for discharging the sheet 2).

According to a eighth aspect of the present invention, there is provided the sheet conveying apparatus according to the seventh aspect, wherein the sheet processing means is a printing apparatus for performing printing on the upper surface of the sheet with ink. Features.

A sheet (printing paper 2) having an upwardly convex shape in a cross section orthogonal to the transport direction is placed on the transport surface (18). The detecting means detects the position of the sheet, and the control means adjusts the position of the conveying means accordingly, so that the conveying means (11) can contact the lower surface of the warped sheet.
That is, the sensor (20) measures the distance from the upper surface of the sheet. The distance between the sensor and the conveying surface is known, and the control means calculates the amount of warpage of the sensor from the distance between the sensor and the upper surface of the sheet and the distance between the sensor and the conveying surface. The control means controls the elevating means (elevating motor 5) to set the position of the upper end of the conveying means to be higher than the inside of the conveying surface by the amount of warpage so that the conveying means (11) can contact the lower surface of the warped sheet. I do. By actuating the conveying means, the warped printing paper is conveyed.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. Sheet conveying device 1 of this example
Is disposed between a printing device (not shown) and the paper discharging device 101 shown in FIGS. 4 and 5, and carries the printed printing paper 2 (sheet) discharged from the printing device into the paper discharging device 101. Used for

As shown in FIG. 1, the base 3 of the present apparatus is attached to a paper discharge device 101. A plurality of vertical guide rods 10 are fixed to the upper surface of the bottom plate 4 of the base 3. The guide rod 10 is provided with a conveying means 11 for the printing paper 2 so as to be able to move up and down. The conveying means 11 includes a support table 8, a pair of pulleys 12 provided on the support table 8, three belts 13 wrapped around the pair of pulleys 12, And a transport motor 14 for driving the pulley 12. The belt 13 is made of urethane which is hardly deteriorated by ink. The belt 13 in this example is a round belt, but may be a flat belt.

An elevating motor 5 as an elevating means is fixed to the upper surface of the bottom plate 4. A feed screw 7 provided on a drive shaft 6 of the lifting motor 5 is engaged with a nut 9 formed on a support base 8. Therefore, if the drive motor 6 is driven to rotate the drive shaft 6, the transporting means 11 can be moved up and down with respect to the bottom plate 4 by being guided by the guide rod.

On the upper surface side of the base 3, a pair of transport guides 1
5, 15 are attached. A pair of transport guides 15
Are arranged on the same plane with the opening 16 interposed therebetween in a direction orthogonal to the transport direction of the printing paper 2. The upper surface of the bottom plate 17 of the transport guide 15 is a transport surface 18 with which the printing paper 2 to be transported contacts. The side plate 19 of the transport guide 15 is
Guide the transport direction of Side plate 19 of transport guide 15
Open at the entrance side of the printing paper 2. The interval between the pair of transport guides 15, that is, the width of the opening 16 is adjustable, and the printing paper 2 having a desired width can be guided.

The transfer means 11 is provided in the opening 16. That is, when the elevating motor 5 raises and lowers the support table 8, the upper half of the belt 13 of the conveying means 11
It is possible to move between a position in the opening 16 in the transport surface 18 and a position above the opening 16.

At a predetermined position above the transport surface 18, a sensor 20 for detecting the printing paper 2 is provided. The sensor 20 detects and outputs the distance to the upper surface of the printing paper 2 on the transport surface 18.

The distance from the sensor 20 to the transport surface 18 is predetermined and constant. The value is stored in the control means 30. The distance between the sensor 20 and the upper surface of the printing paper 2 detected by the sensor 20 is input to the control unit 30. If the printing paper 2 is warped up,
That is, when the projection is upward in a cross section orthogonal to the transport direction, the distance between the sensor 20 and the transport surface 18 is larger than the distance between the sensor 20 and the printing paper 2. The difference between the two distances indicates the amount of warpage of the printing paper 2. The control means 30 calculates the amount of warpage of the printing paper 2 from the distance between the sensor 20 and the transport surface 18 and the distance between the sensor 20 and the printing paper 2 detected by the sensor 20. Then, the control means 30 drives the elevating motor 5 via the motor drive 31 based on the calculated amount of warpage of the printing paper 2 to move the transport means 11. That is, if the upper half portion of the belt 13 of the transport unit 11 is within the transport surface 18, the transport unit 11 is raised by the amount of warpage of the printing paper 2. If the upper half of the belt 13 of the conveying means 11 is already above the conveying surface 18, the belt 13 of the conveying means 11
The conveying means 11 is moved up to a position where the upper half of the printing paper 2 contacts the lower surface of the printing paper 2.

The sensor 20 is a generally used distance measuring sensor having a light emitting unit and a light receiving unit. The distance from the light emitting unit to the center of the light receiving unit is fixed. Light emitted from the light emitting unit is reflected on the surface of the printing paper and received at any position in the light receiving unit. The reflection angle of the light on the surface of the printing paper is obtained from the position where the light is received. The distance between the printing paper and the light emitting unit is obtained from the reflection angle.

The sheet conveying apparatus 1 of this embodiment can convey a flat, undeformed printing paper 2 as well as
As shown in FIG. 2, even a printing sheet 2 whose cross section orthogonal to the conveying direction is convex upward can be conveyed. This is the most different point from the conventional transport device. Therefore, the conveying apparatus of the present embodiment exerts a particularly remarkable effect by being applied to the sheet processing means for discharging such deformed sheets. For example, in a printing apparatus that performs printing on the upper surface of a sheet with ink as in this example, the printing paper 2 is deformed so as to be convex upward in a cross section orthogonal to the conveyance direction. The provision of the sheet conveying device 1 of the present embodiment is effective in that conveyance failures that tend to occur conventionally can be prevented. In addition, examples of a sheet processing apparatus that causes such deformation of a sheet include a lamination processing apparatus, a photographic processing apparatus, a printer of various principles, and a PPC.

The operation of the above configuration will be described. The printing paper 2 printed by the printing device enters the transport guide 15 and rests on the transport surface 18. When the printing paper 2 is bent upward, it cannot be transported because the transport belt 13 is located within the transport surface 18 as shown in FIG.
In this example, the sensor 20 detects the upper surface of the printing paper 2, and the control unit 30 determines the amount of warpage of the printing paper 2. Then, since the control means 30 raises the conveying means 11 according to the determined amount of warpage, the belt 13 of the conveying means 11 can contact the lower surface of the printing paper 2 above the conveying surface 18 as shown in FIG. Belt 1 driven by transport motor 14
Reference numeral 3 conveys the printing paper 2.

When a series of printing papers 2 on which the same image is printed are successively sent from the printing apparatus, the position of the conveying means 11 may be set by measuring the amount of warpage of the first sheet. . This is because if the printing conditions are the same, the warpage amounts of the second and subsequent printing papers 2 are considered to be substantially the same. The printing paper 2 is sequentially stored in the above-described paper discharge device 101.

Although the transporting means 11 of this embodiment has the pulley 12 and the belt 13, it may be constituted by a plurality of rollers.

In the example described above, the conveying means 11 is moved by the elevating motor 5 and set at a position above the conveying surface 18 in accordance with the amount of warpage of the printing paper 2 detected by the sensor 20. However, if the amount of warpage of the sheet to be conveyed is constant and can be predicted, the elevating means and the sensor of the conveying means are not always necessary. That is, the conveying unit is fixed at a position at a predetermined height from the conveying surface according to the assumed amount of sheet warpage. The configuration of the sheet conveying device in this case is substantially the same as that of FIG. 3 except that the sensor 20 is omitted. Needless to say, in this case, since the conveying means 11 is fixed at a position above the conveying surface 18, it is impossible to convey a sheet having a larger amount of warpage than the assumed amount of warpage. However, a sheet having a smaller warp amount than the assumed warp amount or a flat sheet that is not warped can be conveyed.

[0034]

According to the first aspect of the present invention, the conveying means is set above the conveying surface in accordance with the amount of warpage of the sheet to be conveyed, so that even a warped sheet can be conveyed without any trouble. it can.

According to the second aspect of the present invention, the conveying means can be moved up and down with respect to the sheet conveying surface, and the position of the sheet on the elevating surface is detected by the detecting means. Is set above the conveying surface to make contact with the lower surface of the sheet so as to apply a certain conveying force to the sheet. Therefore, according to the present invention, even if the sheet has an upwardly convex shape in a cross section orthogonal to the conveying direction, an effect is obtained that the sheet can be reliably conveyed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention as viewed from a vertical plane parallel to a transport direction of printing paper.

FIG. 2 is a side view of the embodiment of the present invention as viewed from a vertical plane perpendicular to a transport direction of printing paper.

FIG. 3 is a side view of the embodiment of the present invention as viewed from a vertical plane perpendicular to the transport direction of the printing paper.

FIG. 4 is a perspective view of a paper discharge device provided with a conventional transport device.

FIG. 5 is a diagram illustrating a main part of the sheet discharging device.

FIG. 6 is a perspective view of a part of a conventional conveying device and a part of a paper discharging device.

FIG. 7 is a side view of a conventional transport device viewed from a vertical plane perpendicular to the transport direction of printing paper.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet conveyance apparatus 2 Printing paper as a sheet 5 Elevating motor as an elevating means 8 Support base 11 Conveying means 12 Pulley 13 Belt 16 Opening 18 Conveying surface 20 Sensor as a detecting means 30 Control means

Claims (8)

[Claims] 1. A transport surface for transporting a sheet, and a portion that contacts the lower surface of the sheet to contact the lower surface of the sheet on the transport surface and transport the sheet. A sheet transport device having a transport unit configured to be located above. 2. A transport surface for transporting a sheet, transport means for transporting the sheet by contacting a lower surface of the sheet on the transport surface, and at least a portion contacting the lower surface of the sheet with the transport surface. Elevating means for elevating and lowering the conveying means so as to move between a position inside the sheet and a position above the conveying surface; a detecting means for detecting a position of the sheet to be conveyed; and Control means for controlling the elevating means so as to move upward from a position in the conveying surface in accordance with the position of the sheet detected by the means. 3. The sensor according to claim 1, wherein the detection unit is a sensor provided above the conveyance surface and detects and outputs a distance to an upper surface of the sheet on the conveyance surface. Calculate the amount of warpage of the sheet from the difference between the distance to the conveyance surface and the distance from the sensor detected by the sensor to the upper surface of the sheet,
The sheet transport apparatus according to claim 1, wherein the lifting unit is controlled such that a portion of the transport unit that contacts the lower surface of the sheet moves upward from a position in the transport surface by a distance equal to or greater than the warpage amount. 4. The sheet conveying device according to claim 3, wherein an opening is formed at a center of the conveying surface along a conveying direction of the sheet, and the conveying unit is provided in the opening. 5. The transfer means includes a support, a pair of pulleys provided on the support, and a belt wrapped around the pair of pulleys, wherein an upper side of the belt is the transfer surface. Within the opening in the
5. The sheet conveying device according to claim 4, wherein the elevating means raises and lowers the support table so as to be able to move to a position higher than this. 6. The sheet conveying device according to claim 1, wherein the sheet has an upwardly convex shape in a cross section orthogonal to the conveying direction. 7. The sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus is applied to a sheet processing unit that discharges the sheet having a shape that is upwardly convex in a cross section orthogonal to a conveying direction. 8. The sheet conveying device according to claim 7, wherein said sheet processing means is a printing device for performing printing with ink on an upper surface of said sheet.