JP2011111308A - Image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming device which suitably corrects the skew feeding of paper in the image forming device including a pair of register rollers for delivering paper to an image forming part. <P>SOLUTION: The image forming apparatus includes: the pair of register rollers 80 allowing the tip of a transferred material T to once abut on the pair of register rollers 80 in a stop state to curve the transferred material T and then rotationally driven to deliver the transferred material T to the image forming part GK; carrier rollers 90 arranged upstream in a conveying direction D1 of the transferred material T at the pair of register rollers 80 and allowing the tip of the transferred material T to abut on the pair of register rollers 80 while holding the transferred material T to come to a stop; a corrugation member 100 arranged between the pair of register rollers 80 and the carrier rollers 90 and abutting on the transferred material T from the front and rear face sides to form corrugation; and a guide member 130 abutting on the curved transferred material T to press the projecting side thereof to guide the transferred material T to a register nip RN. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copier, a printer, a facsimile, or a complex machine of these.

  Conventionally, as an apparatus for printing (forming) an image on a sheet as a transfer material, an image forming apparatus such as a copier, a printer, or a complex machine of these is known. Generally, in an image forming apparatus, a pair of registration rollers is provided on the upstream side in the sheet transport direction in an image forming unit that forms an image on a sheet. The registration roller pair is a pair of rollers for correcting skew of the paper (oblique feeding) and adjusting timing with the toner image before sending the paper to the image forming unit.

In a stopped state, the registration roller pair temporarily contacts the leading end of the sheet to bend the sheet, and then rotates to send the sheet to the image forming unit.
Specifically, the sheet that is in contact with the stopped registration roller pair is sent out to the registration roller pair side by a conveyance roller disposed on the upstream side of the registration roller pair in the sheet conveyance direction. As a result, the sheet is curved in a state in which the leading end is pressed toward the registration nip formed in the registration roller pair. Here, a reaction force is generated on the sheet in contact with the registration roller pair in a direction opposite to the sheet conveyance direction. Due to the reaction force of the paper, a force is generated on the paper to press the front end portion toward the registration nip. The registration roller pair performs paper skew (oblique feeding) correction before the paper is sent to the image forming unit by pressing the front end of the paper toward the registration nip.

  In the skew (diagonal feeding) correction using the registration roller pair, if the force with which the leading edge of the paper is pressed against the registration roller pair is weak, the paper skew (oblique feeding) correction may not be suitably performed. is there. In addition, when the force with which the leading edge of the paper is pressed against the registration roller pair is strong, the paper enters the registration nip, and thus the paper skew (oblique paper feeding) correction may not be suitably performed.

  Incidentally, the force with which the leading edge of the paper is pressed against the registration roller pair is caused by the size and shape of the curve formed on the paper. Further, the size and shape of the curve formed on the paper are adjusted by the amount of paper fed by the transport roller. In such a technique for adjusting the paper feed amount, there has been proposed an image forming apparatus that adjusts the paper feed amount by the conveying roller in accordance with the degree of paper skew (slanting paper feed) (for example, Patent Documents). 1).

JP-A-5-338859

  However, the force with which the leading edge of the sheet is pressed against the pair of registration rollers is also caused by the thickness and rigidity (strength of the waist) of the sheet. The image forming apparatus described in Patent Document 1 adjusts the sheet feed amount by the transport roller in accordance with the degree of skew of the sheet (oblique feeding), but the thickness and rigidity of the sheet (stretch strength) ) Is not devised any further. Therefore, there has been a demand for an image forming apparatus capable of correcting paper skew (oblique feeding) corresponding to the thickness and rigidity (stretch strength) of the paper.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming apparatus that can suitably perform paper skew (oblique feeding) correction in an image forming apparatus that includes a pair of registration rollers that feed paper to an image forming unit.

  The present invention relates to an image forming unit that forms an image on a sheet-like transfer material and a registration roller pair that forms a registration nip, and in a stopped state, the tip of the transfer material is once applied to the registration roller pair. After the contacted material is bent and curved, the registration roller pair that rotationally drives the transfer material to the image forming unit and the upstream of the registration roller pair in the conveyance direction of the transfer material A conveying roller capable of conveying the transferred material in the conveying direction and stopping the transferred material by holding the transferred material in contact with a pair of registration rollers while holding the transferred material; and the resist A corrugation member disposed between a pair of rollers and the transport roller and abutting the transfer material from the front and back sides to form a corrugation; the registration roller pair and the corrugation An image forming apparatus comprising: a guide member disposed between the guide member and the guide member that contacts the curved transfer target material so as to press the convex side of the curved shape and guides the transfer target material to the registration nip. About.

  The corrugation member is a first rotating roller that is rotatable about a first rotating shaft parallel to the axial direction of the registration roller pair, and is arranged in a plurality along the first rotating shaft. A plurality of second rotations arranged side by side along the second rotation shaft, the second rotation roller being rotatable about a rotation roller and a second rotation axis parallel to the axial direction of the pair of registration rollers It is preferable that the roller includes an overlapping portion where a part of the first rotating roller and a part of the second rotating roller overlap each other when viewed from the first rotating shaft direction and the second rotating shaft direction.

  Further, a corrugation position changing unit that changes the position of the corrugation member in the transport direction by moving the corrugation member along the transport direction of the transfer material, and thickness information relating to the thickness of the transfer material. And / or a position change control unit that controls the corrugation position change unit so as to change the position of the corrugation member in the transport direction based on type information including rigidity information regarding the rigidity of the transfer material. It is preferable.

  An overlapping amount changing unit that changes the amount of the overlapping portion by changing a position of the second rotating roller with respect to the first rotating roller as viewed from the first rotating shaft direction and the second rotating shaft direction; Overlap for controlling the overlap amount changing unit to change the amount of the overlapping portion based on type information including thickness information on the thickness of the transfer material and / or rigidity information on the rigidity of the transfer material. And an amount change control unit.

  According to the present invention, it is possible to provide an image forming apparatus that can suitably perform paper skew (oblique feeding) correction in an image forming apparatus that includes a pair of registration rollers that feed paper to an image forming unit.

FIG. 3 is a diagram for explaining an arrangement of components in the copier 1 according to the first embodiment. FIG. 3 is a side view showing a detailed configuration of a registration mechanism unit RK including a registration roller pair 80 in the copier 1 of the first embodiment. 3 is a perspective view illustrating a detailed configuration of a registration mechanism unit RK including a registration roller pair 80 in the copier 1 of the first embodiment. FIG. FIG. 2 is a front view showing a detailed configuration of a corrugation member 100 that is a component of a registration mechanism unit RK in the copier 1 of the first embodiment. 3 is a flowchart showing an operation flow of skew correction by a registration mechanism unit RK in the copier 1 of the first embodiment. 7 is a side view showing a detailed configuration of the registration mechanism portion RK in a state where the position of the corrugation member 100 is changed to the upstream side in the transport direction D1 of the paper T. FIG. 7 is a side view showing a detailed configuration of the registration mechanism portion RK in a state in which the position of the corrugation member 100 is changed to the downstream side in the transport direction D1 of the paper T. FIG. FIG. 6 is a front view showing a state in which corrugation CG is imparted to paper T by corrugation member 100. FIG. 10 is a side view showing a detailed configuration of a registration mechanism unit RK including a registration roller pair 80 in the copier 1 of the second embodiment. FIG. 10 is a perspective view illustrating a detailed configuration of a registration mechanism unit RK including a registration roller pair 80 in the copying machine 1 according to the second embodiment. 10 is a flowchart showing an operation flow of skew correction by a registration mechanism unit RK in the copier 1 of the second embodiment. FIG. 6 is a side view showing a detailed configuration of a registration mechanism portion RK in a state where an overlap amount of an overlap portion 105 of the corrugation member 100 with a first rotating roller 102 is small. It is a front view which shows the principal part of the registration mechanism part RK in FIG. 11A. FIG. 6 is a side view showing a detailed configuration of a registration mechanism portion RK in a state where an overlap amount of an overlap portion 105 of the corrugation member 100 with a first rotating roller 102 is large. It is a front view which shows the principal part of the registration mechanism part RK in FIG. 12A.

<First Embodiment>
Hereinafter, embodiments of an image forming apparatus of the present invention will be described with reference to the drawings.
With reference to FIG. 1, the overall structure of a copier 1 as an image forming apparatus in the first embodiment will be described. FIG. 1 is a diagram for explaining the arrangement of each component in the copying machine 1 according to the first embodiment.

As shown in FIG. 1, a copier 1 as an image forming apparatus is disposed on an upper side in the vertical direction Z of the copier 1 and on a lower side of the copier 1 in the vertical direction Z. An apparatus main body M that forms a toner image on a sheet T as a sheet-like transfer material based on image information read by the image reading apparatus 300.
In the description of the copying machine 1, the rotation axis direction of various rotating bodies (rollers, belts, etc.) in the photosensitive drum 2, the fixing unit 9, etc. is referred to as “Y direction” (direction passing through FIG. 1). The Y direction is also a direction orthogonal to the transport direction D1 of the paper T as a transfer material (see FIGS. 2 and 3). In the Y direction, the front side in FIG. 1 is also referred to as “+ (plus) side”, and the rear side in FIG. 1 is also referred to as “− (minus) side”. The direction that is horizontal and orthogonal to the Y direction is referred to as the “X direction”. The vertical direction Z of the copier 1 is orthogonal to the X direction and the Y direction. A direction perpendicular to the transport direction D1 of the paper T and perpendicular to the Y direction is referred to as a “second direction D2” (see FIGS. 2 to 4). In the second direction D2, a registration guide member 130 side described later is also referred to as a “+ (plus) side”, and a conveyance guide member 120 side described later is also referred to as a “− (minus) side” (see FIGS. 2 to 4).

First, the image reading apparatus 300 will be described.
As shown in FIG. 1, the image reading apparatus 300 includes a lid member 70 and a reading unit 301 that reads an image of a document G.
The lid member 70 is connected to the reading unit 301 so as to be opened and closed by a connecting unit (not shown). The lid member 70 has a function of protecting a reading surface 302A described later.

Next, the apparatus main body M will be described.
The apparatus body M includes an image forming unit GK that forms a predetermined toner image on the paper T based on predetermined image information, and a fixing unit that fixes the toner image formed on the paper T in the image forming unit GK to the paper T. 9 and a paper supply / discharge unit KH that supplies the paper T to the image forming unit GK and discharges the paper T on which the toner image is formed.

As shown in FIG. 1, the image forming unit GK includes a photosensitive drum 2, a charging unit 10, a laser scanner unit 4 as an exposure device, a developing device 16, a toner cartridge 5, a toner supply device 6, A drum cleaning device 11 and a transfer roller 8 are provided.
The paper supply / discharge unit includes a paper feed cassette 52, a registration roller pair 80, a transport path L for paper T, a paper discharge unit 50, and a manual paper feed unit 64.

  The photosensitive drum 2 is made of a cylindrical member and functions as a photosensitive member or an image carrier. The photosensitive drum 2 is disposed so as to be rotatable in the direction of an arrow about an axis extending in a direction orthogonal to the conveyance direction of the paper T in the conveyance path L. An electrostatic latent image can be formed on the surface of the photosensitive drum 2.

  The charging unit 10 is disposed to face the surface of the photosensitive drum 2. The charging unit 10 uniformly charges the surface of the photosensitive drum 2 to be negative (minus polarity) or positive (plus polarity).

  The laser scanner unit 4 functions as an exposure unit, and is disposed away from the surface of the photosensitive drum 2. The laser scanner unit 4 includes a laser light source (not shown), a polygon mirror, a polygon mirror driving motor, and the like.

  The laser scanner unit 4 scans and exposes the surface of the photosensitive drum 2 based on image information input from a CCD substrate (not shown). By scanning exposure with the laser scanner unit 4, the charge on the exposed portion of the surface of the photosensitive drum 2 is removed. As a result, an electrostatic latent image is formed on the surface of the photosensitive drum 2.

  The developing device 16 is provided corresponding to the photosensitive drum 2 and is disposed to face the surface of the photosensitive drum 2. The developing device 16 attaches a single color (usually black) toner to the electrostatic latent image formed on the photoconductive drum 2 to form a single color toner image on the surface of the photoconductive drum 2. The developing device 16 includes a developing roller 17 disposed opposite to the surface of the photosensitive drum 2, a stirring roller 18 for stirring the toner, and the like.

  The toner cartridge 5 is provided corresponding to the developing device 16 and stores toner supplied to the developing device 16.

  The toner supply device 6 is provided corresponding to the toner cartridge 5 and the developing device 16, and supplies the toner stored in the toner cartridge 5 to the developing device 16. The toner supply device 6 and the developing device 16 are connected by a toner supply path (not shown).

  The transfer roller 8 transfers the toner image developed on the surface of the photosensitive drum 2 to the paper T. A transfer bias for transferring the toner image formed on the photosensitive drum 2 to the paper T is applied to the transfer roller 8 by a transfer bias applying unit (not shown). The transfer roller 8 is configured to be rotatable while being in contact with the photosensitive drum 2.

  A sheet T conveyed on the conveyance path L is sandwiched between the photosensitive drum 2 and the transfer roller 8. The sandwiched paper T is pressed against the surface of the photosensitive drum 2. A transfer nip N is formed between the photosensitive drum 2 and the transfer roller 8. In the transfer nip N, the toner image developed on the photosensitive drum 2 is transferred onto the paper T.

  The drum cleaning device 11 is disposed to face the surface of the photosensitive drum 2. The drum cleaning device 11 removes toner and deposits remaining on the surface of the photosensitive drum 2 and conveys the removed toner and the like to a predetermined collection mechanism for collection.

  The fixing unit 9 melts and presses the toner constituting the toner image transferred to the paper T and fixes the toner on the paper T. The fixing unit 9 includes a heating rotator 9a heated by a heater and a pressure rotator 9b pressed against the heating rotator 9a. The heating rotator 9a and the pressure rotator 9b sandwich and pressurize the paper T on which the toner image has been transferred, and convey the paper T. By transporting the paper T while being sandwiched between the heating rotator 9a and the pressure rotator 9b, the toner transferred onto the paper T is melted and pressurized, and is fixed to the paper T.

Next, the paper supply / discharge unit KH will be described.
As shown in FIG. 1, the paper supply / discharge unit KH includes a cassette paper supply unit 51, a paper supply cassette 52, a manual paper supply unit 64, a transport path L of paper T, a registration roller pair 80, and paper discharge. Part 50. As will be described later, the transport path L includes the first transport path L1, the second transport path L2, the third transport path L3, the fourth transport path L4, the fifth transport path L5, and the sixth transport. This is an assembly of the path L6 and the return transport path LB.

  As shown in FIG. 1, in the lower part of the apparatus main body M, two paper feed cassettes 52 that store paper T are arranged in the left and right (X direction). The paper feed cassette 52 is configured to be drawable in the horizontal direction from the front side (the front side in FIG. 1) of the apparatus main body M. The paper feed cassette 52 includes a placement plate 60 on which the paper T is placed, and is accommodated in a state where the paper T is stacked on the placement plate 60. When an image is formed on the paper T, the paper T placed on the placement plate 60 is placed at the paper feed side end of the paper feed cassette 52 (right end in FIG. 1). 51 is sent out to the conveyance path L. The cassette paper feed unit 51 includes a forward feed roller 61 for taking out the paper T on the placement plate 60 and a paper feed roller pair 63 for feeding the paper T one by one to the first transport path L1 of the transport path L. A double feed prevention mechanism.

  A manual paper feed unit 64 is provided on the right side of the apparatus main body M (on the right side in FIG. 1) and above the paper feed cassette 52. The manual paper feed unit 64 is provided mainly for supplying the apparatus main body M with a paper T of a size and type different from the paper T set in the paper feed cassette 52. The manual paper feed unit 64 includes a manual feed tray 65 that forms a part of the front surface of the apparatus main body M in the closed state, and a paper feed roller 66. The lower end of the manual feed tray 65 is attached to the vicinity of the paper feed roller 66 so as to be rotatable (openable and closable). The paper T is placed on the open manual feed tray 65. The paper feed roller 66 feeds the paper T placed on the open manual feed tray 65 to the first transport path L1.

The conveyance path L includes a first conveyance path L1 from the cassette paper feeding unit 51 to the registration roller pair 80, a second conveyance path L2 from the registration roller pair 80 to the transfer roller 8, and a transfer roller 8 to the fixing unit 9. The third transport path L3, the fourth transport path L4 from the fixing unit 9 to the first branching section Q1, the fifth transport path L5 from the first branching section Q1 to the paper discharge section 50, and the fourth transport path L4 A return transport path LB for transporting the paper T transported from the upstream side to the downstream side from the first branching portion Q1 to the second joining portion P2, and a sixth transport for transporting the paper T reversed upside down to the paper discharge portion 50. And a road L6.
Details of the registration mechanism RK including the registration roller pair 80 will be described later.

  A first junction P1, a second junction P2, and a third junction P3 are disposed in the first transport path L1. The first merging portion P1 is a merging portion from the cassette sheet feeding portion 51 of the two sheet feeding cassettes 52 to the first transport path L1. The second junction P2 is a junction from the return conveyance path LB to the first conveyance path L1. The third merging portion P3 is a merging portion from the manual sheet feeding portion 64 to the first transport path L1.

  The return conveyance path LB includes a bent conveyance path La that conveys the sheet T branched at the first branching portion Q1 while being bent obliquely downward, and a sheet T that is turned upside down by the bending conveyance through the second branching portion Q2. After that, the horizontal receiving portion Lb received in a horizontal posture, and the paper T that is once received by the horizontal receiving portion Lb and then fed in the reverse direction are branched at the third branching portion Q3, and again are reversed upside down. And a horizontal return transport path Lc for transporting toward the second junction P2. A roller pair 28 that forcibly conveys the paper T that is turned upside down to the horizontal return conveyance path Lc or the sixth conveyance path L6 through the third branching section Q3 is provided at the delivery end of the horizontal receiving section Lb. Yes. Further, the first branch part Q1, the second branch part Q2, and the third branch part Q3 are provided with transport path switching members 30, 31, and 32, respectively.

  When the double-sided printing of the paper T is performed, the return transport path LB reverses the front and back and the front and back of the paper T after being fixed by the fixing unit 9, thereby reversing the surface that has been printed (non-printing). This is a transport path for transporting so that the surface) faces the photosensitive drum 2. Further, the sixth transport path L6 passes through the bent transport path La in the return transport path LB, and is discharged in a state where the paper T once received by the horizontal receiving portion Lb is turned upside down (in a state where the printing surface is down). This is a conveyance path for carrying out to the paper unit 50.

  A paper discharge unit 50 is provided above the left side (left side in FIG. 1) of the apparatus main body M. The paper discharge unit 50 opens toward the left side of the apparatus main body M. The paper discharge unit 50 discharges the paper T transported through the fifth transport path L5 or the paper T transported through the sixth transport path L6 onto a paper discharge tray 54 outside the apparatus main body M by the roller pair 53.

  Hereinafter, a configuration related to the registration mechanism unit RK, which is a characteristic part of the copying machine 1 of the first embodiment, will be described with reference to the drawings. FIG. 2 is a side view showing a detailed configuration of the registration mechanism unit RK including the registration roller pair 80 in the copier 1 of the first embodiment. FIG. 3 is a perspective view showing a detailed configuration of the registration mechanism unit RK including the registration roller pair 80 in the copying machine 1 according to the first embodiment. FIG. 4 is a front view showing a detailed configuration of the corrugation member 100 that is a component of the registration mechanism RK in the copier 1 of the first embodiment.

  As shown in FIG. 2, the registration mechanism RK of the first embodiment includes a registration roller pair 80, a first conveyance roller pair 90 as a conveyance roller, a corrugation member 100, a conveyance guide member 120, and a guide member. The resist guide member 130, the sensor S, and the corrugation position changing unit 140 are provided.

The registration roller pair 80 is disposed on the upstream side in the transport direction D1 of the paper T in the transfer nip N of the image forming unit GK (see FIG. 1).
The registration roller pair 80 is composed of two roller members facing each other. The two roller members in the registration roller pair 80 are configured to be rotatable around a rotation axis parallel to the Y direction. A motor (not shown) is connected to the registration roller pair 80. The registration roller pair 80 rotates or stops by driving a motor.

A registration nip RN is formed between the two roller members in the registration roller pair 80. The paper T conveyed on the first conveyance path L1 is conveyed toward the registration nip RN.
The leading end of the paper T that is transported through the first transport path L1 contacts the resist roller pair 80 that is stopped. The sheet in contact with the registration roller pair 80 is sent out in the conveyance direction D1 by a first conveyance roller pair 90 described later, and in the second direction on the upstream side of the conveyance direction D1 of the registration nip RN in the first conveyance path L1. Curved convexly on the plus side in D2.
In this way, the registration roller pair 80 bends the paper T by temporarily abutting the leading end portion of the paper T conveyed on the first conveyance path L1 when the registration roller pair 80 is in a stopped state.

  After the leading end portion of the paper T once comes into contact with the registration roller pair 80, the registration roller pair 80 is driven to rotate. Thereby, the paper T is introduced into the registration nip RN. The paper T introduced into the registration nip RN is sent out to the second conveyance path L2 by the registration roller pair 80 while being sandwiched between two roller members in the registration roller pair 80. As described above, the registration roller pair 80 sends the paper T toward the transfer nip N in the image forming unit GK.

  The first conveyance roller pair 90 is disposed on the upstream side in the conveyance direction D1 of the paper T in the registration roller pair 80. Specifically, the first conveyance roller pair 90 is a conveyance roller pair that is positioned closest to the registration roller pair 80 among a plurality of conveyance roller pairs that convey the paper T toward the image forming unit GK.

  The first transport roller pair 90 is composed of two roller members facing each other. The registration roller pair 80 is configured to be rotatable about a rotation axis parallel to the rotation axis direction. A conveyance roller driving unit 910 configured by a motor or the like is connected to the first conveyance roller pair 90. The first conveyance roller pair 90 rotates or stops by driving the conveyance roller driving unit 910. As a result, the first transport roller pair 90 feeds the paper T toward the registration roller pair 80 in a state where the paper T is sandwiched between the two roller members.

The first transport roller pair 90 transports the paper T in the transport direction D1, and brings the leading end of the paper T into contact with the registration roller pair 80 with the paper T being sandwiched. The first transport roller pair 90 feeds the paper T in a state where the paper T is sandwiched by driving of the transport roller driving unit 910, and causes the leading end of the paper T to contact the registration roller pair 80. The first conveying roller pair 90 bends the paper T by feeding the paper T in contact with the registration roller pair 80 further to the registration roller pair 80 side. The first conveying roller pair 90 sends out the paper T whose tip end is in contact with the registration roller pair 80 so as to bend in a convex shape toward the plus side in the second direction D2.
The first conveying roller pair 90 stops rotating after the paper T is sent out for a predetermined length.

The delivery length of the paper T in the first conveying roller pair 90 is set for each apparatus according to various design conditions. In the present embodiment, the first transport roller pair 90 is transported based on a passing signal of the paper T output by a sensor S (described later) disposed on the upstream side of the registration roller pair 80 in the transport direction of the paper T. The roller drive unit 910 is rotated for a predetermined time. Thereby, the paper T is sent out for a predetermined length in the transport direction D1. As a result, the paper T is curved in a convex shape on the plus side in the second direction D2.
As described above, the first conveying roller pair 90 presses the leading end portion of the sheet T against the registration roller pair 80, thereby correcting the skew (oblique feeding) of the sheet T before the sheet T is sent to the image forming unit GK. ing.

  As shown in FIGS. 2 to 4, the corrugation member 100 is disposed between the registration roller pair 80 and the first conveyance roller pair 90. The corrugation member 100 includes a first rotation shaft member 101 coaxial with the first rotation shaft J1 extending in parallel with the rotation shaft direction of the registration roller pair 80, and a plurality of first rotation rollers rotatable about the first rotation shaft J1. 102, a second rotating shaft member 103 coaxial with the second rotating shaft J2 extending in parallel with the rotating shaft direction of the registration roller pair 80, and a plurality of second rotating rollers 104 rotatable about the second rotating shaft J2. Have.

  The plurality of first rotating rollers 102 are fixed to the first rotating shaft member 101. The plurality of first rotating rollers 102 are arranged at regular intervals along the direction in which the first rotating shaft J1 of the first rotating shaft member 101 extends. The plurality of second rotating rollers 104 are fixed to the first rotating shaft member 101. The plurality of second rotating rollers 104 are arranged at regular intervals along the direction in which the second rotating shaft J2 of the second rotating shaft member 103 extends.

  In each of the plurality of first rotating rollers 102 and each of the plurality of second rotating rollers 104, the diameter is, for example, 10 mm to 14 mm. The length of the first rotation roller 102 in the first rotation axis J1 direction is, for example, 6 mm to 12 mm. The length of the second rotation roller 104 in the second rotation axis J2 direction is, for example, 6 mm to 12 mm. The interval between the adjacent first rotation rollers 102 and 102 in the first rotation axis J1 direction is, for example, 60 mm to 80 mm. The interval between the adjacent second rotation rollers 104 and 104 in the second rotation axis J2 direction is, for example, 60 mm to 80 mm.

The plurality of first rotating rollers 102 and the plurality of second rotating rollers 104 are alternately arranged when viewed from a direction orthogonal to the first rotation axis J1 direction and the second rotation axis J2 direction.
The first rotating roller 102 is disposed at the center between the second rotating rollers 104 and 104 adjacent in the direction of the first rotation axis J1. The second rotating roller 104 is disposed at the center between the first rotating rollers 102 and 102 adjacent to each other in the second rotating shaft J2 direction.

  When viewed from the direction of the rotation axis of the first rotation axis J1 and the second rotation axis J2, a part of the first rotation roller 102 and a part of the second rotation roller 104 overlap each other, that is, an overlap part 105. (See FIGS. 2 and 4). For the overlap amount OL of the overlap portion 105, for example, the overlapping length in the second direction D2 is set to 1 mm to 2 mm. Since the corrugation member 100 has an overlap portion 105, the first rotation roller 102 and the second rotation roller 104 abut on the paper T from both the front and back surfaces, thereby forming a corrugation CG (see FIG. 7) on the paper T.

  As shown in FIG. 3, the corrugation member 100 is configured such that the first rotating roller 102 and the second rotating roller 104 can rotate to the first roller holder 109 via the first rotating shaft member 101 and the second rotating shaft member 103, respectively. It is integrated by being supported. The corrugation member 100 is configured to be movable along the transport direction D1 of the paper T by a corrugation position changing unit 140 described later.

The first roller holder 109 includes a first flat plate portion 106, a first vertical plate portion 107, a second vertical plate portion 108, and a third vertical plate portion 110.
The first flat plate portion 106 is formed to extend along the axial direction (Y direction) of the second rotation axis J2 on the minus side of the second rotation roller 104 in the second direction D2. The first vertical plate portion 107 is formed to extend perpendicularly from the first flat plate portion 106 to the positive side in the second direction D2 at the positive side end portion of the first flat plate portion 106 in the Y direction. The third vertical plate portion 110 is formed to extend perpendicularly from the first flat plate portion 106 to the positive side in the second direction at the negative end portion in the Y direction of the first flat plate portion 106. The second vertical plate portion 108 is in the vicinity of the third vertical plate portion 110 and at a position spaced apart from the third vertical plate portion 110 to the positive side in the Y direction, and is positive from the first flat plate portion 106 in the second direction D2. It extends perpendicularly to the side.

  Both ends of the first rotating shaft member 101 and the second rotating shaft member 103 are rotatably supported by the first vertical plate portion 107 and the second vertical plate portion 108 in the first roller holder 109. Accordingly, the first rotating roller 102 and the second rotating roller 104 are supported by the first vertical plate portion 107 and the second vertical plate portion 108 so as to be rotatable about the first rotating shaft J1 and the second rotating shaft J2. .

  A drive motor 111 is attached to the third vertical plate portion 110. A pair of gears 112 and 113 that mesh with each other are fixed to the negative side ends of the first rotating shaft member 101 and the second rotating shaft member 103 in the Y direction. Further, the gear 112 of the first rotating shaft member 101 meshes with a gear 114 that is fixed to the output shaft of the drive motor 111.

  In the corrugation member 100, when the driving rotational force of the driving motor 111 is transmitted to the pair of gears 112 and 113 via the gear 114, the first rotating roller 102 and the second rotating roller 104 are moved in the direction of the arrow shown in FIG. Rotate to. Accordingly, the corrugation member 100 is configured to form the corrugation CG on the paper T and to transport the paper T on which the corrugation CG is formed toward the registration roller pair 80 side.

  The conveyance guide member 120 and the registration guide member 130 are arranged so that the distance between them becomes narrower as it approaches the position immediately before the registration roller pair 80 in the first conveyance path L1. As a result, the paper T sent out from the first conveyance roller pair 90 is guided by the conveyance guide member 120 and the registration guide member 130 and conveyed toward the registration nip RN.

The conveyance guide member 120 is a planar plate member. The conveyance guide member 120 is formed on one surface side (minus side in the second direction D2) of the conveyed paper T between the first conveyance roller pair 90 and the registration roller pair 80. The conveyance guide member 120 is formed to be interrupted at a position where the corrugation member 100 is disposed.
The conveyance guide member 120 conveys the paper T sent out from the first conveyance roller pair 90 toward the registration roller pair 80 on one surface side (surface opposite to the printing surface).

  The resist guide member 130 is a planar plate member. The registration guide member 130 is disposed between the registration roller pair 80 and the corrugation member 100 and is formed on the other surface side (printing surface side) of the conveyed paper T. The registration guide member 130 is positioned in the vicinity of the registration nip RN at the downstream end in the transport direction D1, and approaches the transport guide member 120 toward the downstream end in the transport direction D1 (second direction D2). (Minus side).

  The resist guide member 130 is disposed in an inclined posture having an inclination of, for example, 20 ° to 25 ° with respect to the YD1 plane (horizontal plane in FIG. 2). The registration guide member 130 abuts the paper T curved in a convex shape by the front end of the paper T abutting the registration roller pair 80 so as to press the convex side of the curved shape. Guide to RN.

  The sensor S is disposed along the first conveyance path L1 between the registration roller pair 80 and the first conveyance roller pair 90. The sensor S detects that the paper T has passed and outputs a detection signal.

  As shown in FIGS. 2 and 3, the corrugation position changing unit 140 is connected to a pair of rails 141, 141, a pair of sliding movement members 142, 142, a timing belt 143, and a pair of timing pulleys 145, 146. A plate member 144 and a position change drive unit 149 are provided.

The pair of rails 141, 141 are the first vertical plate portion 107 of the first flat plate portion 106 on the positive side end portion side and the negative side end portion side of the first flat plate portion 106 of the first roller holder 109. The second vertical plate portion 108 is disposed in parallel to each other along the transport direction D1 of the paper T on the surface opposite to the surface on which the second vertical plate portion 108 is disposed.
The pair of sliding movement members 142, 142 are a first vertical plate in the first flat plate portion 106 on the positive side end side and the negative side end side of the first flat plate portion 106 of the first roller holder 109. The portion 107 and the second vertical plate portion 108 are fixed to the surface opposite to the surface on which the portion 107 and the second vertical plate portion 108 are disposed. The pair of sliding movement members 142 and 142 are fitted to the pair of rails 141 and 141 and configured to be movable along the transport direction D1. Accordingly, the corrugation member 100 is configured to be movable along the transport direction D1 of the paper T.

  The pair of timing pulleys 145 and 146 are spaced apart from each other in the transport direction D1 on the surface of the first flat plate portion 106 on the side opposite to the first vertical plate portion 107 at the positive side end in the Y direction. The timing pulleys 145 and 146 are formed in a columnar shape with a short height. The timing pulleys 145 and 146 are configured to be rotatable around a rotation axis parallel to the first rotation axis J1. One timing pulley 145 is configured to be able to drive forward and reverse rotation and stop rotation by a position change drive unit 149. The position change drive unit 149 is configured by, for example, a motor.

  The timing belt 143 is stretched around a pair of timing pulleys 145 and 146. The timing belt 143 contacts the outer peripheral surfaces of the pair of timing pulleys 145 and 146. The timing belt 143 rotates or stops when one of the timing pulleys 145 drives to rotate forward and backward and stops rotating. The timing belt 143 is disposed along the outer side surface of the plus-side rail 141 in the Y direction.

  The corrugation position changing unit 140 moves the corrugation member 100 along the conveyance direction D1 of the paper T by causing the position change driving unit 149 to drive the timing belt 143 to rotate forward and backward, thereby moving the position of the corrugation member 100 in the conveyance direction D1. To change. Specifically, by changing the position of the corrugation member 100 along the transport direction D1 of the paper T, the interval between the registration roller pair 80 and the corrugation member 100 is adjusted to be in the range of 80 to 100 mm, for example. can do.

Next, a configuration related to the control of the copy machine 1 will be described.
As shown in FIGS. 2 and 3, the copier 1 includes a control unit 200 and a storage unit 250. The control unit 200 includes a position change control unit 210 and a conveyance roller drive control unit 220.
The position change control unit 210 changes the position of the corrugation member 100 in the transport direction D1 based on the type information of the paper T including the thickness information about the thickness of the paper T and the rigidity information about the rigidity of the paper T. The corrugation position changing unit 140 is controlled.

  The position change control unit 210 is based on the type information of the paper T including the thickness information about the thickness of the paper T and the rigidity information about the rigidity of the paper T selected by the paper type selection button (not shown) of the copier 1. The movement amount (position change amount) of the corrugation position changing unit 140 is determined with reference to information stored in the storage unit 250 described later, and the determined operation amount is output to the corrugation position changing unit 140.

  The transport roller drive control unit 220 controls the transport roller drive unit 910 to stop the rotation of the first transport roller pair 90 after a predetermined time based on the information of the detection signal of the paper T detected by the sensor S. To do. As a result, the first transport roller pair 90 feeds the paper T, the front end of which is in contact with the registration roller pair 80, to the registration roller pair 80 side by a predetermined length. As a result, the sheet T is bent in a state where the leading end is in contact with the registration roller pair 80.

  The storage unit 250 stores information related to the operation amount of the corrugation position changing unit 140 corresponding to the paper type. Information stored in the storage unit 250 is referred to by the position change control unit 210.

Incidentally, the paper T having various thicknesses is used in the copying machine 1. When the thickness of the paper T is different, the rigidity (strength of the waist) is different corresponding to the thickness of the paper T. Further, even for the paper T having the same thickness, various types (stiffness) of paper T are selectively used such that the rigidity (strength) differs depending on the material. .
Then, depending on the type (rigidity) of the paper T to be used, a difference occurs in the force with which the leading end of the paper T is pressed against the registration roller pair 80 (hereinafter also referred to as “tip pressing force”). The difference is one of the factors that prevent the skew correction from being performed properly.

  The registration mechanism portion RK in the first embodiment has a function of adjusting the tip pressing force that varies depending on the type (rigidity) of the paper T to be used. Specifically, the registration mechanism unit RK adjusts the leading edge pressing force by increasing the rigidity of the paper T using the corrugation member 100. The corrugation member 100 is formed by forming a corrugation CG (see FIG. 7) on the paper T by causing the first rotating roller 102 and the second rotating roller 104 having the overlap portion 105 to contact the paper T from both the front and back surfaces. The rigidity of the paper T to be used is increased.

In this embodiment, the corrugation member 100 forms a corrugation CG that extends in the transport direction D1 on the paper T (see FIGS. 6A to 7). Therefore, when the paper T is the same type, the actual rigidity of the paper T on which the corrugation CG is formed is higher than the rigidity of the paper T on which the corrugation CG is not formed in the transport direction D1 of the paper T.
Specifically, the paper T on which the corrugation CG is formed is formed in the transport direction D1 more than the paper T on which the corrugation CG is not formed by forming a plurality of corrugations on the paper T along the transport direction D1. Hard to bend (strong waist).

Further, the corrugation position changing unit 140 changes the position at which the rigidity of the paper T is increased, so that the leading edge pressing force when the leading edge of the paper T abuts against the registration roller pair 80 affects the type of the paper T. Adjust so that it is within the set range. Specifically, the corrugation position changing unit 140 changes the position of the corrugation member 100 in the transport direction D1 of the paper T. In this case, the corrugation CG formed on the paper T disappears in front of the upstream side in the conveyance direction D1 of the convex vertex of the curved shape. That is, the corrugation CG formed on the paper T disappears before reaching the registration nip RN.
The position change control unit 210 determines the position change amount of the corrugation position change unit 140 with reference to information stored in the storage unit 250 based on the type information of the paper T to be used. Then, the position change control unit 210 controls the corrugation position change unit 140.

Next, the operation of the copier 1 of the first embodiment will be briefly described with reference to FIG.
First, a case where single-sided printing is performed on the paper T stored in the paper feed cassette 52 will be described.
The paper T accommodated in the paper feed cassette 52 is sent out to the first transport path L1 by the forward feed roller 61 and the paper feed roller pair 63, and then the registration rollers via the first junction P1 and the first transport path L1. Transported to pair 80.
In the registration roller pair 80, skew correction of the paper T and timing adjustment with the toner image are performed. The skew correction operation by the registration mechanism RK including the registration roller pair 80 will be described later.

The paper T discharged from the registration roller pair 80 is introduced into the transfer nip N between the photosensitive drum 2 and the transfer roller 8 via the first conveyance path L1. In the transfer nip N, the toner image developed on the photosensitive drum 2 is transferred onto the paper T.
Thereafter, the sheet T is discharged from the transfer nip N between the photosensitive drum 2 and the transfer roller 8 to the second conveyance path L2, and is added to the heating rotator 9a in the fixing unit 9 via the second conveyance path L2. It is introduced into the fixing nip with the pressure rotating body 9b. Then, in the fixing nip, the toner TN is melted and pressed, and the toner TN is fixed on the paper T.

Next, the paper T is transported to the paper discharge unit 50 through the third transport path L3, and is discharged from the paper discharge unit 50 onto the paper discharge tray 54 outside the apparatus main body M by the roller pair 53.
In this way, single-sided printing of the paper T stored in the paper feed cassette 52 is completed.

  When single-sided printing is performed on the paper T placed on the manual feed tray 65, the paper T placed on the manual feed tray 65 is sent out to the manual feed path L by the paper feed roller 66, and then the third joining portion. It is transported to the first transport path L1 via P3, and transported to the registration roller pair 80 via the first transport path L1. Subsequent operations are the same as the one-side printing operation of the paper T accommodated in the paper feed cassette 52 described above, and a description thereof will be omitted.

Next, the operation of the copier 1 when performing duplex printing will be described.
In the case of single-sided printing, as described above, the paper T on which single-sided printing has been performed is discharged from the paper discharge unit 50 to the outside of the apparatus body M, and the printing operation is completed.
On the other hand, when performing double-sided printing, the paper T on which single-sided printing has been performed is reversed from the time of single-sided printing and conveyed again to the registration roller pair 80 via the return conveyance path LB. Then, printing is performed on the surface (non-printing surface) opposite to the surface on which the paper T has already been printed, and the double-sided printing is completed.

  Next, a specific operation of skew correction by the registration mechanism unit RK, which is a characteristic part of the copier 1 of the first embodiment, will be described with reference to FIGS. 5, 6A, 6B, and 7. FIG. FIG. 5 is a flowchart showing an operation flow of skew correction by the registration mechanism unit RK in the copier 1 of the first embodiment. FIG. 6A is a side view showing a detailed configuration of the registration mechanism RK in a state in which the position of the corrugation member 100 is changed to the upstream side in the transport direction D1 of the paper T. FIG. 6B is a side view showing a detailed configuration of the registration mechanism RK in a state in which the position of the corrugation member 100 is changed to the downstream side in the transport direction D1 of the paper T. FIG. 7 is a front view showing a state where the corrugation CG is imparted to the paper T by the corrugation member 100.

In step ST101, the type of paper T used for printing is selected by a paper type selection button (not shown) of the copier 1.
In step ST102, the position change control unit 210 determines the operation amount (position change amount) of the corrugation position change unit 140 with reference to the storage unit 250 based on the type (rigidity) information of the selected paper T. . The position change control unit 210 outputs information related to the operation amount of the corrugation position change unit 140 to the corrugation position change unit 140.

  In step ST <b> 103, the position change drive unit 149 drives the timing belt 143 to rotate forward and backward in the corrugation position change unit 140 based on the information on the operation amount determined and output by the position change control unit 210. Thereby, the corrugation member 100 is moved along the transport direction D1 of the paper T. Accordingly, the position of the corrugation member 100 in the transport direction D1 is changed.

  Here, when the rigidity of the selected paper T is large (strong), as shown in FIG. 6A, the corrugation member 100 is located upstream in the transport direction D1 so as to be separated from the registration roller pair 80. The position is changed. On the other hand, when the rigidity of the selected paper T is small (the waist is weak), as shown in FIG. 6B, the corrugation member 100 is positioned on the downstream side in the transport direction D1 so as to be close to the registration roller pair 80. Is changed.

  In step ST104, the sheet T conveyed in the conveyance direction D1 while being sandwiched between the first conveyance roller pair 90 passes between the first rotation roller 102 and the second rotation roller 104 of the corrugation member 100. . In this case, as shown in FIG. 7, the first rotating roller 102 and the second rotating roller 104 come into contact with the paper T from the front and back sides. Accordingly, a plurality of corrugations CG are formed on the paper T at regular intervals in the width direction orthogonal to the transport direction of the paper T. By forming a plurality of corrugations CG, the rigidity of the paper T is increased.

In step ST <b> 105, the paper T on which the corrugation CG is formed is sent out along the transport direction D <b> 1 of the paper T by the first transport roller pair 90.
The paper T sent out to the first conveyance roller pair 90 is detected by a sensor S disposed along the first conveyance path L1 between the registration roller pair 80 and the first conveyance roller pair 90. The sensor S outputs information on the detection signal of the paper T to the transport roller drive control unit 220. Based on the information output from the sensor S, the transport roller drive control unit 220 causes the transport roller drive unit 910 to stop the rotation of the first transport roller pair 90 after a predetermined time.

Thereby, the paper T on which the corrugation CG is formed comes into contact with the registration roller pair 80 in which the leading end of the paper T is stopped. Then, a portion (curved portion) Ta following the leading end portion of the paper T is curved in a convex shape on the plus side in the second direction D2 (see FIGS. 6A and 6B).
When the corrugation member 100 is positioned close to the registration roller pair 80 (see FIG. 6B), the corrugation member 100 is positioned away from the registration roller pair 80. The size of the convex second direction D2 is smaller than that of the case (see FIG. 6A).

The curved sheet T is guided toward the registration nip RN in a state where the convex side of the curved shape is pressed by the registration guide member 130.
The plurality of corrugations CG disappears on the upstream side in the transport direction D1 from the convex vertex of the curved portion Ta due to the formation of the curved portion Ta. Here, the leading edge pressing force when the leading edge of the paper T abuts against the registration roller pair 80 is less affected by the type of the paper T because the plurality of corrugations CG are held halfway along the curved portion Ta. It is suitably adjusted.

  Specifically, as shown in FIG. 6A, when the rigidity of the selected paper T is large (high stiffness), the corrugation member 100 is used when the rigidity of the selected paper T is small (low waist). It is positioned on the upstream side in the transport direction D1 so as to be further away from the registration roller pair 80. Further, as shown in FIG. 6B, when the rigidity of the selected paper T is small (the waist is weak), the corrugation member 100 resists more than when the rigidity of the selected paper T is large (the waist is strong). It is positioned on the downstream side in the transport direction D1 so as to be close to the roller pair 80.

  For this reason, the plurality of corrugations CG formed on the paper T disappears on the upstream side in the transport direction D1 with respect to the convex vertex of the curved portion Ta when the paper T is transported. When the corrugation member 100 is positioned close to the registration roller pair 80, the corrugation member 100 is held closer to the registration roller pair 80 than when the corrugation member 100 is positioned apart from the registration roller pair 80.

  Therefore, when the corrugation member 100 is positioned close to the registration roller pair 80, the rigidity of the sheet T is higher than that when the corrugation member 100 is positioned away from the registration roller pair 80. The side close to the pair 80 is held. As a result, the leading edge pressing force when the leading edge of the paper T abuts against the registration roller pair 80 is adjusted by changing the position of the corrugation member 100.

  As described above, the leading edge pressing force is suitably adjusted, the leading edge pressing force is insufficient, and skew (diagonal feeding) correction cannot be performed accurately, or the leading edge pressing force is excessive, and the leading edge of the paper T is excessive. Does not enter the registration nip RN and skew (oblique sheet feeding) correction cannot be performed accurately. Therefore, it is difficult to be affected by the type (rigidity) of the paper T, and appropriate skew correction is performed.

  In step ST106, after the skew correction of the paper T, the registration roller pair 80 is driven to rotate. The paper T is sent out toward the transfer nip N of the image forming unit GK. In this case, the skew-corrected sheet T is guided to the registration nip RN when the convex side of the curved portion Ta of the sheet T comes into contact with the registration guide member 130.

According to the copying machine 1 of the first embodiment, the following effects are exhibited.
In the copying machine 1 according to the first embodiment, the registration roller pair 80 that forms the registration nip RN, and in a stopped state, the leading edge of the paper T is once brought into contact with the registration roller pair 80 to bend the paper T. Thereafter, the registration roller pair 80 that rotates and feeds the paper T to the image forming unit GK and the upstream side of the registration roller pair 80 in the conveying direction D1 are in contact with the paper T from both the front and back sides and corrugated CG to the paper T. And a resist guide member 130 that abuts the curving side of the curved paper T so as to press the curved convex side and guides the paper T to the resist nip RN.

Therefore, by forming the corrugation CG on the paper T, it is possible to increase the rigidity of the paper T and increase the front end pressing force with which the front end of the paper T is pressed against the registration roller pair 80.
Thereby, for example, even when the paper T with low rigidity (low stiffness) is used, the shortage of the leading edge pressing force can be solved and the skew correction of the paper T can be suitably performed.

Further, in the copier 1 of the first embodiment, the corrugation member 100 can rotate around the first rotation axis J1 parallel to the axial direction of the registration roller pair 80, and is aligned along the first rotation axis J1. The plurality of first rotation rollers 102 arranged and the second rotation axis J2 parallel to the axial direction of the registration roller pair 80 are rotatable around the plurality of first rotation rollers J2 arranged side by side along the second rotation axis J2. An overlap portion 105 is formed between a part of the first rotary roller 102 and a part of the second rotary roller 104.
For this reason, it is possible to reliably and smoothly form a corrugation CG along the width direction of the paper T without damaging the paper T.
Thereby, the rigidity of the paper T and the leading edge pressing force can be increased by forming the corrugation CG, and the skew correction of the paper T can be performed reliably and appropriately.

Further, in the copier 1 of the first embodiment, the corrugation position change for changing the position of the corrugation member 100 in the transport direction D1 based on the type information of the paper T including the thickness information and / or the rigidity information of the paper T. A position change control unit 210 that controls the unit 140 and the corrugation position change unit 140.
Therefore, when using a wide variety of sheets T having different thicknesses and rigidity, the position of the corrugation member 100 in the transport direction D1 is changed so that it is not easily affected by the type of the sheet T, and the leading end of the sheet T is a registration roller. The tip pressing force when abutting against the pair 80 can be suitably adjusted. For example, by performing a button operation for selecting the type of the paper T to be used, the front end pressing force when the front end of the paper T abuts against the registration roller pair 80 is suitably adjusted based on the type information of the paper T. Is possible.
As a result, it is possible to prevent skew correction due to insufficient tip pressing force or excessive tip pressing force, and even when using various types (stiffness) of paper T, it is reliable and appropriate. Skew correction can be performed.

Second Embodiment
Next, the copier 1 of the second embodiment will be described. FIG. 8 is a side view showing a detailed configuration of the registration mechanism unit RK including the registration roller pair 80 in the copying machine 1 according to the second embodiment. FIG. 9 is a perspective view illustrating a detailed configuration of the registration mechanism unit RK including the registration roller pair 80 in the copying machine 1 according to the second embodiment.
The second embodiment will be described mainly with respect to differences from the first embodiment. The same components as those in the first embodiment will be denoted by the same reference numerals, and detailed description thereof will be omitted. In the second embodiment, the description of the first embodiment is appropriately applied to points that are not particularly described. Also in the second embodiment, the same effects as in the first embodiment are achieved.

  As shown in FIG. 8, the second embodiment is different from the first embodiment in that the registration mechanism unit RK includes an overlap amount change unit 160 and the control unit 200 includes an overlap amount change control unit 215. Mainly different from 1.

  As shown in FIG. 9, the corrugation member 100 according to the second embodiment is disposed between the registration roller pair 80 and the first conveyance roller pair 90. The corrugation member 100 includes a first rotation shaft member 101 coaxial with the first rotation shaft J1 extending in parallel with the rotation shaft direction of the registration roller pair 80, and a plurality of first rotation rollers rotatable about the first rotation shaft J1. 102, a second rotating shaft member 103 coaxial with the second rotating shaft J2 extending in parallel with the rotating shaft direction of the registration roller pair 80, and a plurality of second rotating rollers 104 rotatable about the second rotating shaft J2. Have.

  An end portion on the plus side in the Y direction of the first rotating shaft member 101 is rotatably supported on the apparatus main body M side via a bearing member 161. A drive motor 162 is connected to the positive end of the first rotating shaft member 101 in the Y direction.

  The second rotating shaft member 103 is rotatably supported by the second roller holder 166. The second roller holder 166 is biased to the minus side in the second direction D2 by a biasing member (not shown). The second roller holder 166 includes a second flat plate portion 163, a fourth vertical plate portion 164, and a fifth vertical plate portion 165. The second flat plate portion 163 is formed to extend along the second rotation axis J2 direction (Y direction) on the minus side of the second direction of the second rotation roller 104 extending in the Y direction. The fourth vertical plate portion 164 is formed to extend vertically from the second flat plate portion 163 to the positive side in the second direction at the positive end portion in the Y direction of the second flat plate portion 163. The fifth vertical plate portion 165 is formed to extend vertically from the second flat plate portion 163 to the positive side in the second direction at the negative end portion in the Y direction of the second flat plate portion 163.

  Both end portions of the second rotating shaft member 103 are rotatably supported by the fourth vertical plate portion 164 and the fifth vertical plate portion 165 in the second roller holder 166. Thus, the second rotating roller 104 is supported by the fourth vertical plate portion 164 and the fifth vertical plate portion 165 so as to be rotatable about the second rotation axis J2.

The registration mechanism unit RK of the second embodiment has an overlap amount changing unit 160.
The overlap amount changing unit 160 changes the overlap amount (overlap amount) OL of the overlap portion 105 between the first rotating roller 102 and the second rotating roller 104 in the corrugation member 100.
The overlap amount changing unit 160 includes a cam rotation shaft member 167 and eccentric cams 168 and 168. The cam rotation shaft member 167 is formed long in the second rotation axis J2 direction (Y direction) along the second flat plate portion 163 on the minus side of the second flat plate portion 163 of the second roller holder 166 in the second direction. The

The eccentric cams 168 and 168 are fixed to both ends of the cam rotation shaft member 167. The cam surfaces of the eccentric cams 168 and 168 are in contact with the negative surface of the second flat plate portion 163 of the second roller holder 166 in the second direction D2.
The cam rotation shaft member 167 to which the eccentric cams 168 and 168 are fixed is configured to be able to drive forward and reverse rotation and stop rotation by an overlap amount changing drive unit 169. The overlap amount changing drive unit 169 is configured by, for example, a motor.

  The eccentric cams 168 and 168 are rotated by the rotation of the cam rotation shaft member 167 by the overlap amount changing drive unit 169. As the eccentric cams 168 and 168 rotate, the second roller holder 166 is moved to the plus side or the minus side in the second direction D2. Accordingly, the position of the second rotating roller 104 supported by the second roller holder 166 is changed in the second direction D2.

  The overlapping amount changing unit 160 rotates the first rotating shaft J1 and the second rotating shaft J2 by rotating the eccentric cams 168 and 168 by driving the cam rotating shaft member 167 forward and reverse by the overlapping amount changing driving unit 169. When viewed from the axial direction, the positions of the second roller holder 166 and the second rotating roller 104 in the second direction D2 with respect to the first rotating roller 102 are changed. Thereby, the overlap amount changing unit 160 can adjust the overlap amount OL of the overlap portion 105 so that, for example, the overlapping length in the second direction D2 is in the range of 0.5 to 2.0 mm. .

The control unit 200 according to the second embodiment includes an overlap amount change control unit 215.
The overlap amount change control unit 215 refers to the information stored in the storage unit 250 based on the thickness information related to the thickness of the paper T and the type information of the paper T including the rigidity information related to the rigidity of the paper T. The operation amount of the amount changing unit 160 (a change amount to the plus side or the minus side in the second direction D2) is determined, and the determined operation amount is output to the overlap amount changing unit 160.

  The storage unit 250 stores information regarding the operation amount of the overlap amount change control unit 215 corresponding to the paper type. Information stored in the storage unit 250 is referred to the overlap amount change control unit 215.

  Next, a specific operation of skew correction by the registration mechanism unit RK, which is a characteristic part in the copier 1 of the second embodiment, will be described with reference to FIGS. 10, 11A, 11B, 12A, and 12B. . FIG. 10 is a flowchart illustrating an operation flow of skew correction by the registration mechanism unit RK in the copying machine 1 according to the second embodiment. FIG. 11A is a side view showing a detailed configuration of the registration mechanism portion RK when the overlap amount of the overlap portion 105 of the corrugation member 100 with the first rotating roller 102 is small. FIG. 11B is a front view showing a main part of the registration mechanism RK in FIG. 11A. FIG. 12A is a side view showing a detailed configuration of the registration mechanism portion RK when the overlap amount of the overlap portion 105 of the corrugation member 100 with the first rotating roller 102 is large. 12B is a front view showing a main part of the registration mechanism RK in FIG. 12A.

In step ST201, the type of paper T to be used for printing is selected by a paper type selection button (not shown) of the copying machine 1.
In step ST202, the overlap amount change control unit 215 refers to the information stored in the storage unit 250 based on the type (rigidity) information of the selected paper T, and operates the operation amount (position) of the overlap amount change unit 160. Change amount). The overlap amount change control unit 215 outputs information related to the operation amount of the overlap amount change unit 160 to the overlap amount change unit 160.

  In step ST203, based on the operation amount information determined and output by the overlap amount change control unit 215, the overlap amount change drive unit 169 drives the eccentric cams 168 and 168 in the overlap amount change unit 160 to rotate. Therefore, the second rotating roller 104 in the corrugation member 100 is moved to the plus side or the minus side in the second direction D2. As a result, the overlap amount OL of the overlap portion 105 between the first rotating roller 102 and the second rotating roller 104 is changed.

  Here, when the selected paper T has a large rigidity (strong), the second rotating roller 104 in the corrugation member 100 is over the first rotating roller 102 as shown in FIGS. 11A and 11B. The position is changed in the direction away from the first rotating roller 102 in the second direction D2 so that the overlap amount OL of the wrap portion 105 is reduced. On the other hand, when the rigidity of the selected paper T is small (the waist is weak), as shown in FIGS. 12A and 12B, the second rotating roller 104 is over the overlap portion 105 with the first rotating roller 102. The position is changed in the direction approaching the first rotating roller 102 in the second direction D2 so that the wrap amount OL increases.

  In step ST204, the paper T conveyed in the conveyance direction D1 while being sandwiched between the first conveyance roller pair 90 passes between the first rotation roller 102 and the second rotation roller 104 of the corrugation member 100. . In this case, as shown in FIG. 11B and FIG. 12B, the first rotating roller 102 and the second rotating roller 104 abut on the paper T from the front and back sides. Accordingly, a plurality of corrugations CG are formed on the paper T at regular intervals in the width direction orthogonal to the transport direction of the paper T.

  When the overlap amount OL of the corrugation member 100 is changed to be small for the paper T having high rigidity (strong waist), a corrugation CG with small unevenness is formed. On the other hand, when the overlap amount OL of the corrugation member 100 is largely changed for the paper T having low rigidity (low stiffness), the corrugation CG having large unevenness is formed. Thus, a plurality of corrugations CG corresponding to the type (rigidity) of the paper T is formed on the paper T. Accordingly, even when various types of paper T are used, the rigidity of the paper T is increased.

In step ST205, the paper T on which the corrugation CG is formed is transported in the transport direction D1 of the paper T by the first transport roller pair 90.
The paper T sent out to the first conveyance roller pair 90 is detected by a sensor S disposed along the first conveyance path L1 between the registration roller pair 80 and the first conveyance roller pair 90. The sensor S outputs information on the detection signal of the paper T to the transport roller drive control unit 220. Based on the information output from the sensor S, the transport roller drive control unit 220 causes the transport roller drive unit 910 to stop the rotation of the first transport roller pair 90 after a predetermined time.

Thereby, the paper T on which the corrugation CG is formed comes into contact with the registration roller pair 80 in which the leading end of the paper T is stopped. Then, a portion (curved portion) Ta following the leading end portion of the paper T is curved in a convex shape on the plus side in the second direction D2 (see FIGS. 11A and 12A).
The curved portion Ta formed on the paper T is more convex than when the overlap amount OL of the corrugation member 100 is large (see FIG. 12A) and when the overlap amount OL of the corrugation member 100 is small (see FIG. 11A). The size of the two directions D2 is small.

The curved sheet T is guided toward the registration nip RN in a state where the convex side of the curved shape is pressed by the registration guide member 130.
The plurality of corrugations CG disappears on the upstream side in the transport direction D1 from the convex vertex of the curved portion Ta due to the formation of the curved portion Ta. Here, the leading edge pressing force when the leading edge of the paper T abuts against the registration roller pair 80 is suitably adjusted without being influenced by the type of the paper T by forming a plurality of corrugations CG.

  Specifically, as shown in FIG. 11A, when the rigidity of the selected paper T is large (high stiffness), the overlap amount OL of the corrugation member 100 is changed to be small. Further, as shown in FIG. 12A, when the rigidity of the selected paper T is small (the waist is weak), the overlap amount OL of the corrugation member 100 is greatly changed.

  Therefore, the plurality of corrugations CG formed on the paper T disappears on the upstream side in the transport direction D1 with respect to the convex vertex of the curved portion Ta when the paper T is transported, but the overlap amount OL of the corrugation member 100 When is large, the corrugation CG having large irregularities is formed as compared with the case where the overlap amount OL of the corrugation member 100 is small, so that the corrugation member 100 is held close to the registration roller pair 80.

  Accordingly, when the overlap amount OL of the corrugation member 100 is large, the rigidity of the paper T is held closer to the registration roller pair 80 than when the overlap amount OL of the corrugation member 100 is small. As a result, the leading edge pressing force when the leading edge of the paper T abuts against the registration roller pair 80 is adjusted by changing the overlap amount OL of the corrugation member 100.

  By suitably adjusting the leading edge pressing force in this way, the leading edge pressing force is insufficient and skew (oblique feeding) correction cannot be performed accurately, or the leading edge pressing force is excessive and the leading edge of the paper T is not aligned. There is no possibility that the skew (oblique feeding) correction cannot be performed accurately due to entering the resist nip RN. Therefore, it is difficult to be affected by the type (rigidity) of the paper T, and appropriate skew correction is performed.

  In step ST206, after skew correction of the paper T, the registration roller pair 80 is driven to rotate. The paper T is sent out toward the transfer nip N of the image forming unit GK. In this case, the skew-corrected sheet T is guided to the registration nip RN when the convex side of the curved portion Ta of the sheet T contacts the registration guide member 130.

According to the copying machine 1 of the second embodiment, the following effects are produced.
In the copying machine 1 according to the second embodiment, the first rotating roller 102 and the second rotating roller 104 constituting the corrugation member 100 based on the type information of the paper T including the thickness information and / or the rigidity information of the paper T. And an overlap amount change unit 160 that changes the overlap amount OL of the overlap portion 105 and an overlap amount change control unit 215 that controls the overlap amount change unit 160.

Therefore, based on the type information of the paper T, in the case of the paper T with low rigidity, the overlap amount is increased to form a corrugation CG with large unevenness on the paper T. Further, in the case of the paper T having high rigidity, the overlap amount OL is reduced to form a corrugation CG with small unevenness on the paper T. Thereby, it is difficult to be influenced by the type of the paper T, and it is possible to suitably adjust the front end pressing force when the front end of the paper T abuts against the registration roller pair 80.
As a result, it is possible to prevent skew correction due to insufficient tip pressing force or excessive tip pressing force, and even when using various types (stiffness) of paper T, it is reliable and appropriate. Skew correction can be performed.

The preferred embodiments of the present invention have been described above, but the present invention is not limited to the first and second embodiments described above, and can be implemented in various forms.
For example, in the first embodiment, the timing belt 143 is used in the configuration of the corrugation position changing unit 140, but a fluid pressure cylinder may be used instead.
In the second embodiment, the eccentric cams 168 and 168 are used in the configuration of the overlap amount changing unit 160, but a fluid pressure cylinder may be used instead.

  In the second embodiment, the configuration in which the overlap amount OL of the overlap portion 105 in the corrugation member 100 is changed is configured to move the second rotating roller 104 with respect to the first rotating roller 102. Not limited to. For example, the first rotating roller 102 may be configured to move with respect to the second rotating roller 104.

  Further, the number of the plurality of first rotating rollers 102 and the plurality of second rotating rollers 104 in the corrugation member 100 is not limited.

The type of the image forming apparatus of the present invention is not particularly limited, and may be a copier, a printer, a facsimile, or a complex machine thereof.
Further, the sheet-like transfer material is not limited to paper, and may be a film sheet, for example.

  DESCRIPTION OF SYMBOLS 1 ... Copy machine (image forming apparatus), 80 ... Registration roller pair, 90 ... Conveyance roller pair (conveyance roller), 100 ... Corrugation member, 130 ... Registration guide member (guide member), T ... Paper (Transfer material), Ta: Curved portion, RN: Registration nip, GK: Image forming portion

Claims (4)

An image forming unit for forming an image on a sheet-like transfer material;
A pair of registration rollers that form a registration nip, and in a stopped state, the tip of the material to be transferred is once brought into contact with the pair of registration rollers to bend the material to be transferred, and then rotated to drive the material to be transferred. A pair of registration rollers for feeding the material to the image forming unit;
The registration roller pair is disposed upstream of the transfer material in the conveyance direction, conveys the transfer material in the conveyance direction, and holds the transfer material in a state where the tip of the transfer material is nipped. A transport roller that can be stopped by contacting the registration roller pair;
A corrugation member that is disposed between the pair of registration rollers and the conveyance roller, and forms a corrugation by contacting the transfer material from the front and back sides;
A guide member that is disposed between the registration roller pair and the corrugation member and abuts the curved transfer material so as to press the convex side of the curved shape, and guides the transfer material to the registration nip. When,
An image forming apparatus comprising:   The corrugation member is a first rotation roller that is rotatable about a first rotation axis parallel to the axial direction of the registration roller pair, and a plurality of first rotations arranged side by side along the first rotation axis. A plurality of second rotating rollers that are arranged around the second rotating shaft, the second rotating roller being rotatable about a second rotating shaft parallel to the axial direction of the registration roller pair; 2. The image according to claim 1, further comprising an overlapping portion where a part of the first rotating roller and a part of the second rotating roller overlap each other when viewed from the first rotating shaft direction and the second rotating shaft direction. Forming equipment. A corrugation position changing unit that changes the position of the corrugation member in the transport direction by moving the corrugation member along the transport direction of the transfer material;
The corrugation position changing unit is configured to change the position of the corrugation member in the transport direction based on type information including thickness information on the thickness of the transfer material and / or rigidity information on the rigidity of the transfer material. A position change control unit for controlling
The image forming apparatus according to claim 1, further comprising: An overlapping amount changing unit that changes the amount of the overlapping portion by changing the position of the second rotating roller with respect to the first rotating roller as viewed from the first rotating shaft direction and the second rotating shaft direction;
Overlap for controlling the overlap amount changing unit to change the amount of the overlapping portion based on type information including thickness information on the thickness of the transfer material and / or rigidity information on the rigidity of the transfer material. An amount change control unit;
An image forming apparatus according to claim 2.

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