JP2011026048A - Method of manufacturing double-sided recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively restrain paper floating in double-sided recording, by managing its direction (to which direction the large (small) direction of an outer diameter is turned), when installing a plurality of driven rollers. <P>SOLUTION: An inkjet printer 1 recordable on both surfaces of paper has a carrying driving roller 35 and carrying driven rollers 36 (36A-36F) arranged in a plurality at a proper interval along its axial direction. In a manufacturing process of the inkjet printer 1, in an installation process of the carrying driven rollers 36, among the carrying driven rollers 36 arranged in a plurality, at least a set of adjacent carrying driven rollers 36 are arranged in a predetermined position so that the large side L of an outer diameter of a roller outer peripheral surface faces each other. Thus, the paper extending effect is provided, and the paper floating is restrained. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a double-sided recording apparatus capable of recording on both sides of a recording medium.

  Hereinafter, an ink jet printer as an example of a recording apparatus will be described as an example. The ink jet printer includes a transport unit that transports a recording sheet as an example of a recording medium on the upstream side of the ink jet recording head. The conveying means is configured to include a driving roller that is rotationally driven and a driven roller that is driven to rotate while being pressed against the driving roller, and the driving roller rotates while pinching the recording paper between the driving roller and the driven roller. By doing so, the recording paper is conveyed to a region facing the ink jet recording head.

  Examples of conventional driven rollers that are driven to rotate while being pressed against the driving roller include those shown in Patent Documents 1 to 3. As shown in Patent Documents 1 to 3, the driven rollers are often formed by resin molding, and a plurality of driven rollers are arranged at appropriate intervals in the paper width direction.

JP-A-11-286348 Japanese Patent Laid-Open No. 11-314789 JP 2001-97593 A

  As described above, the driven roller is often formed by resin molding, but even if the roller outer peripheral diameter is to be formed uniformly in the length direction of the roller, it is not necessarily uniform due to the molding factor. In particular, the outer diameter of the one end portion in the roller length direction tends to be larger (smaller) than the outer diameter of the other end portion.

  Molding factors that cause such uneven roller outer diameter include, for example, mold shrinkage, mold accuracy, punch taper considering punching from the mold, and positions near and far from the mold gate position in injection molding. And the difference in resin pressure between and the like. And in the conventional inkjet printer, the direction of the roller length direction (whether the larger outer diameter (smaller one) is directed to which side) was not managed when the driven roller was assembled.

  Incidentally, some ink jet printers are configured so that recording paper on which recording is performed on the first surface can be reversed and recording on the second surface can be executed, that is, recording on both sides is possible. When recording is performed on the first side, the recording sheet absorbs ink and swells, and cockling (waving) may be formed. May be noticeable. As a result, the recording quality may be reduced.

  In particular, an inkjet printer may be provided with a guide member (also referred to as a platen) provided with a plurality of ribs that are arranged to face a recording head and support a recording sheet as a recording medium at an appropriate interval along the sheet conveying direction. is there. This is because regular ribs (cockling) are formed by ribs on paper that swells upon absorbing ink, thereby keeping the distance between the paper and the recording head (hereinafter referred to as “paper gap”) as uniform as possible. Because of that.

  In such an ink jet printer, when the recording paper on which the recording is performed on the first surface is reversed, the portion that was the crest of the cockling at the time of recording on the first surface becomes the trough of the second surface. A portion that was a valley of cockling when recording on one surface is a mountain on the second surface. That is, when recording is performed on the second surface, the cock ring has already been formed, and the valley of the second surface (the peak of the first surface) is supported by the rib. The mountain (the first surface valley) is more prominently floated.

  Further, as described above, the sheet floating at a predetermined position in the sheet width direction may be noticeable due to other apparatus configurations (such as a roller arrangement position) instead of the rib arrangement position.

  Then, as described above, the applicant of the present application manages the orientation of the driven roller in which the outer diameter of the one end in the roller length direction is larger (smaller) than the outer diameter of the other end. Thus, it has been found that the above-described lifting of the paper can be suppressed.

  This invention is made | formed in view of such a condition, The objective is managing the direction (Which direction (a direction with a large (small) outer diameter is directed)) when assembling a plurality of driven rollers. Thus, it is to effectively suppress sheet floating during double-sided recording.

  In order to solve the above-described problem, a method for manufacturing a double-sided recording apparatus according to the first aspect of the present invention includes a recording unit that performs recording on a recording medium and a direction that intersects the conveyance direction of the recording medium as appropriate. And a second roller that nips the recording medium between the first roller and the first roller, and the recording medium is moved by rotating the first roller and the second roller. The recording medium transporting means transported to the recording position by the recording means and the second surface opposite to the first surface of the recording medium recorded by the recording means are opposed to the recording means. A recording medium reversing unit that reverses the recording medium and sends the recording medium to the recording medium conveying unit side, wherein the both sides of the first roller in the length direction of the roller are provided. About outer diameter The inspection step for inspecting which side is larger, and at least one pair of adjacent first rollers among the plurality of first rollers arranged so that the side with the larger outer diameter of the roller outer peripheral surface faces each other in the roller length direction And a roller assembling step for disposing at a predetermined position.

  According to this aspect, at least one pair of adjacent first rollers among the plurality of first rollers arranged is arranged at a predetermined position so that the larger outer diameter sides of the roller outer peripheral surfaces face each other in the roller length direction. Therefore, in the transport area by the pair of first rollers (hereinafter referred to as “extension transport area”), the transport direction of the recording medium is directed from the intermediate position of the two first rollers toward both outer sides. .

  As a result, the recording medium is given a tendency to be stretched at the intermediate position between the two first rollers. In other words, a “wrinkle stretching effect” is obtained (stretching effect). Even if a significant float (mountain) occurs during recording on the second surface due to the influence of the above, it can be reduced. As a result, it is possible to prevent the recording medium from being lifted when the recording on the second surface is executed, and to obtain good recording quality.

  Note that the position at which the pair of first rollers that exhibit such an extension effect should be arranged (the extension conveyance area setting position), that is, the “predetermined position”, can be appropriately set in relation to the floating of the recording medium. It is a matter. That is, the position where the floating of the recording medium becomes noticeable when recording on the second surface differs depending on the apparatus configuration. Can be sought. And it becomes possible to reduce the said float by arrange | positioning the said 1st pair of 1st roller in the position where the float becomes remarkable like that, or its vicinity.

  According to a second aspect of the present invention, in the first aspect, the double-sided recording apparatus is disposed so as to face the recording head, and a rib that supports the recording medium is along a direction intersecting a conveyance direction of the recording medium. A plurality of recording medium guide members provided at an appropriate interval are provided, and in the roller assembling step, an intermediate position between the at least one pair of adjacent first rollers in the direction intersecting the transport direction is the most distant interval. It is set between two said ribs with large adjacent.

  The remarkable floating that occurs during recording on the second surface due to the effect of recording on the first surface is likely to occur between two adjacent ribs, particularly between two adjacent ribs having the largest arrangement interval. easy. Therefore, by setting the intermediate position of the first roller pair in such a position, it is possible to effectively prevent the recording medium from being lifted when recording on the second surface, and to achieve good recording quality. Can be obtained.

  According to a third aspect of the present invention, in the second aspect, in the roller assembling step, the outer side of the first roller that should be disposed on one side with the middle position of the pair of adjacent first rollers as a boundary. The large diameter sides are all arranged in the same direction, and the large outside diameter side of the first roller to be arranged on the other side is also arranged in the same direction.

  Regarding the other first rollers excluding the first set of rollers that exerts the extension effect, there are two roller sets in which the smaller outer diameter faces each other, as opposed to the first set of first rollers. When it exists, there exists a possibility that the reverse action of the said extension effect, ie, the effect | action to the direction where a float becomes large may arise.

  However, according to this aspect, with the middle position of the pair of adjacent first rollers as a boundary, the large-diameter side of the first roller to be disposed on one side is all disposed in the same direction. In addition, since the large outer diameter side of the first roller to be arranged on the other side is also arranged in the same direction, a roller set in which the small outer diameter sides are arranged to face each other does not occur, that is, the above-described extension effect The reverse action of can be prevented.

FIG. 3 is a side cross-sectional view illustrating a paper conveyance path of the inkjet printer according to the present invention. FIG. 2 is a plan view of a main part of the inkjet printer according to the present invention. (A) is a top view of a conveyance driven roller, (B) is the same sectional drawing. (A) is principal part sectional drawing of the metal mold | die for primary forming of a conveyance driven roller, (B) is principal part sectional drawing of the metal mold | die for secondary molding. The flowchart which shows from the formation process of a conveyance driven roller to an assembly | attachment process in the manufacturing process of an inkjet printer. (A) is a principal part top view of the inkjet printer which concerns on this invention, (B) is the figure which represented typically the shape and direction of a conveyance driven roller. The figure which shows the state of the paper floating at the time of performing recording on the 2nd surface (back surface) of a paper. (A)-(D) are the variations which changed the combination of a pair of conveyance follower roller arrange | positioned so that the side with a large outer diameter might face each other.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view showing a sheet conveyance path of an inkjet printer 1 which is an embodiment of a “double-sided recording apparatus” according to the present invention, FIG. 2 is a plan view of a principal part of the inkjet printer 1, and FIG. The top view of the driven roller 36, (B) is the same sectional view.

  4A is a cross-sectional view of the main part of the primary molding die of the transport driven roller 36, FIG. 4B is a cross-sectional view of the main part of the secondary molding die, and FIG. FIG. 6A is a plan view of the main part of the inkjet printer 1 and FIG. 6B schematically shows the shape and orientation of the transport driven roller 36 in the manufacturing process, from the molding process to the assembly process of the transport driven roller 36. FIGS. 7A and 7B are diagrams illustrating a state of sheet floating when recording is performed (before execution) on the second surface (back surface) of the sheet. FIGS. 8A to 8D are diagrams showing variations in which the combination of the pair of transport driven rollers 36 arranged so that the large outer diameter sides L face each other is changed.

  Note that FIG. 1 illustrates the rollers arranged on the paper transport path of the ink jet printer 1 so that almost all the rollers are drawn on the same surface, but in the depth direction (the front and back sides in FIG. 1). The positions do not necessarily match (in some cases, they match).

  In the following, the left-right direction in FIG. 1 and the up-down direction in FIGS. 2 and 6 are referred to as the sheet conveyance direction, and the direction orthogonal to the sheet conveyance direction, that is, the front and back direction in FIG. The left-right direction is referred to as the paper width direction or the main scanning direction.

■■■ Overall configuration of inkjet printer ■■■
The overall configuration of the inkjet printer 1 will be outlined below with reference to FIGS. 1 and 2. The ink jet printer 1 includes a feeding device 2 at the bottom of the device, and from the feeding device 2, a sheet of recording paper (mainly cut sheet paper: hereinafter referred to as “paper P” as appropriate) as an example of a recording medium. The recording unit 4 performs ink jet recording, and discharges the sheet toward a discharge stacker (not shown) provided on the front side of the apparatus (right side in FIG. 1).

  Further, the ink jet printer 1 includes a reversing unit 7 which is detachable at the rear of the apparatus, and a second surface (back surface) opposite to the first surface (front surface) of the paper P on which recording was first performed. Is reversed so that it faces the recording head 42, whereby recording can be executed on both sides of the paper P.

Hereinafter, the components on the paper transport path will be described in more detail.
The feeding device 2 includes a paper cassette 11, a pickup roller 16, a guide roller 20, and a separating unit 21. A plurality of sheets P can be set in a stacked state in the sheet cassette 11 that can be loaded and removed from the front side of the apparatus, and the sheet P accommodated by an edge guide (not shown) is positioned at the feeding position. It has become.

  A pickup roller 16 that is rotationally driven by a motor (not shown) is provided on a swinging member 17 that swings about a swinging shaft 18, and is in contact with the uppermost one of the sheets P set in the sheet cassette 11. By rotating, the uppermost sheet P is sent out from the sheet cassette 11.

  The paper P to be fed is preliminarily separated by the separation slope 12 and then reaches the separation means 21 while being guided by the guide roller 20. The separation roller 22 constituting the separation means 21 is provided in a state in which an outer peripheral surface is formed of an elastic material and can be pressed against the drive roller 23 and given a predetermined rotational resistance. Accordingly, the next and subsequent sheets P to be double fed are stopped between the separation roller 22 and the driving roller 23, that is, double feeding is prevented.

  On the downstream side of the separating means 21, a driving roller 26 that is driven to rotate by a motor (not shown) and an assist roller 27 that is driven to rotate by nipping the paper P between the driving roller 26 are provided. A first intermediate feeding unit 25 is provided, and the first intermediate feeding unit 25 feeds the paper P further downstream.

  The paper P fed by the first intermediate feeding unit 25 passes through the driven roller 29 and is driven to rotate by driving the paper roller nip between the driving roller 32 and the driving roller 32 that is rotated by a motor (not shown). The second intermediate feed unit 31 configured to include the assist roller 33 is reached. Then, the second intermediate feeding portion 31 further feeds downstream.

  The recording unit 4 is disposed on the downstream side of the second intermediate feeding unit 31. The recording unit 4 includes a transport unit 5, a recording head 42, a lower guide member 39, and a discharge unit 6. Note that a paper detection means (not shown) for detecting the passage of the paper P is also provided in the vicinity of the upstream side of the transport means 5.

  The transport means 5 includes a transport drive roller 35 as a “second roller” that is rotationally driven by a motor, and a “first roller” that is pivotally supported by the upper guide member 37 so as to be driven to rotate while being pressed against the transport drive roller 35. And a transport driven roller 36.

  The transport driving roller 35 is a single shaft body in which a high friction material is attached to the outer peripheral surface of a metal shaft extending in the paper width direction. The transport driven roller 36 is an axial direction (paper width direction) of the transport driving roller 35. ) Are arranged at appropriate intervals (in the present embodiment, six). In FIG. 2 (and FIG. 6), subscripts (A to F) are added to distinguish each of the plurality of transport driven rollers 36 arranged in the paper width direction.

  A plurality of upper guide members 37 that pivotally support the transport driven roller 36 are arranged along the axial direction of the transport drive roller 35 (two in the present embodiment). In the present embodiment, one upper guide member 37 is Three conveyance driven rollers 36 are pivotally supported via a rotation shaft 34 (FIG. 3). The upper guide member 37 is provided so as to be swingable about a swing shaft (not shown), and is urged by a coil spring 38 in a direction in which the transport driven roller 36 is in pressure contact with the transport drive roller 35.

  The paper P that has reached the transport means 5 is precisely fed to the downstream side (recording position by the recording head 42) as the transport drive roller 35 rotates while being nipped by the transport drive roller 35 and the transport driven roller 36. Is done.

  Here, the rotation center of the conveyance driven roller 36 is set slightly downstream from the rotation center of the conveyance drive roller 35, and the traveling direction of the paper P sent out from between the two rollers is thereby determined by the recording head 42. A predetermined entry angle is formed with respect to the upper surface of the lower guide member 39, not in parallel with the head surface. Thereby, the sheet P is prevented from being lifted from the lower guide member 39, and the distance between the recording surface of the sheet P and the recording head 42 is appropriately maintained.

  Subsequently, the recording head 42 to which ink is supplied from an ink cartridge (not shown) is provided at the bottom of the carriage 40. The carriage 40 is guided by a carriage guide shaft 41 extending in the main scanning direction, and a drive motor (not shown). Is driven to reciprocate in the main scanning direction.

  A lower guide member 39 is provided at a position facing the recording head 42, and ribs R <b> 1 to R <b> 3 extending in the sheet transport direction are provided at appropriate intervals in the sheet width direction on the surface of the lower guide member 39 facing the recording head 42. A plurality are formed in the space. The sheet P is supported from below by the ribs R1 to R3, whereby the distance between the sheet P and the recording head 42 is defined.

  In FIG. 2 (and FIG. 6), the plurality of ribs R1 formed at appropriate intervals in the paper width direction are denoted by reference numerals 51 to 63, respectively. In addition, each rib is drawn with hatching to clearly show its position. In the present embodiment, the plurality of ribs R1 are provided at positions where paper edges of several sizes that are planned to be used can be supported from below.

  Therefore, in the region where the difference in paper size is not large, the arrangement interval of the ribs R1 is narrow (for example, the ribs 62 to 63). In FIG. 2 (and FIG. 6), reference numeral X1 indicates a reference position in the paper width direction, that is, indicates that one edge of all paper passes through the reference position X1. Reference numeral X2 indicates a position through which the other edge of the A4 size sheet passes.

  Further, in FIG. 2 (and FIG. 6), reference numeral Y1 is an area where the rib R1 is formed, reference numeral Y3 is an area where the rib R2 is formed, reference numeral Y5 is an area where the rib R1 is formed, and reference numeral Y2 is the rib R1 and rib. A region between R2 and symbol Y4 indicate a region between the ribs R2 and R3.

  Next, the ribs R <b> 1 to R <b> 3 are formed inside a recess formed in the lower guide member 39, and the ink absorbing material Q that absorbs the ink ejected to the region protruding from the edge of the paper P in this recess. Is provided. As an example, when ink is ejected to the leading edge region of the paper and the region protruding from the leading edge of the paper with the leading edge positioned above the area Y2, marginless recording is performed on the leading edge of the paper and the paper is protruding. Ink is absorbed by the ink absorbing material Q.

  On the downstream side of the recording head 42, an auxiliary roller 43 that restricts the sheet floating from the lower guide member 39 and a discharge unit 6 that discharges the recorded sheet P are provided. The discharge means 6 includes a discharge drive roller 44 that is rotationally driven by a motor (not shown), and a discharge driven roller 45 that is driven to rotate in contact with the discharge drive roller 44, and is a sheet on which recording is performed by the recording means 4. P is discharged by the discharge means 6 to a stacker (not shown) provided on the front side of the apparatus.

  The auxiliary roller 43, the discharge driving roller 44, and the discharge driven roller 45 are arranged at appropriate intervals in the sheet width direction as shown in FIG. The auxiliary roller 43 and the discharge driven roller 45 are pivotally supported by the frame 49 so as to be freely rotatable.

  Subsequently, the reversing unit 7 constituting the recording medium reversing means includes a large-diameter reversing roller 46 and assist rollers 46 and 47 that are driven to rotate while nipping the paper P between the reversing roller 46. The sheet P that has been fed out from the sheet cassette 11 and recorded on the first surface (front surface) is subjected to the reverse feeding operation of the second intermediate feeding unit 31, the conveying unit 5, and the discharging unit 6 by the reverse feeding operation. The side that was the trailing edge of the sheet when recording is performed on one side becomes the leading edge, and is drawn between the reversing roller 46 and the assist roller 47.

  The reversing roller 46 is rotationally driven in a counterclockwise direction in FIG. 1 by a motor (not shown), and the paper drawn between the reversing roller 46 and the assist roller 47 is the reversing roller 46 and the assist roller 46. The second intermediate feeding unit 31 is reached again through the gap, guided to the recording means 4, and recording is performed on the second surface (back surface).

■■■ Construction and manufacturing method of transport driven roller ■■■
The outline of the inkjet printer 1 has been described above, and the conveyance driven roller 36 and the manufacturing method (molding process) will be described in detail below with reference to FIGS. 3 and 4.
As shown in FIGS. 3A and 3B, the transport driven roller 36 includes an inner layer 36A in which a shaft hole 36b through which the rotation shaft 34 is inserted, and an outer layer 36B formed outside the inner layer 36A and in contact with the paper. It is configured with.

  The outer peripheral surface 36a of the conveyance driven roller 36 (the outer peripheral surface of the outer layer 36B) is configured by a straight portion S1 parallel to the rotation axis and an inclined portion S2 formed so as to decrease in diameter toward the roller end portion. Although the straight portion S1 is set parallel to the rotational axis by design, it is not actually parallel to the rotational axis due to the molding factor, and the outer diameter of one end is the same as the other end. It becomes larger than the outer diameter (details will be described later).

  In the inner layer 36A, at least one side (end surface indicated by reference numeral 36e) of the end surface in the rotation axis direction is positioned inside (inside) the outer layer 36B, in other words, the end surface 36e is recessed by retracting to the inner side from the end surface 36g of the outer layer 36B. 36c is formed. Thereby, the surfaces in which movement in the rotation axis direction is restricted by the upper guide member 37 (FIG. 1) are the end surface 36g of the outer layer 36B and the end surface 36f of the inner layer 36A.

  Further, a large diameter portion 36d having a diameter larger than that of the shaft hole 36b is formed on the side of the end surface 36f opposite to the end surface 36e located inside the outer layer 36B in the inner layer 36A. Therefore, in a state where the transport driven roller 36 is supported by the upper guide member 37 and is urged toward the transport drive roller 35, the rotation shaft 34 inserted through the shaft hole 36 b is on both sides in the rotation axis direction of the transport driven roller 36. An escape portion is formed.

  Next, such a transport driven roller 36 can form the inner layer 36A by the first color of two-color molding, for example, and can form the outer layer 36B by the second color (details will be described later). Here, as the resin used for the inner layer 36A and the outer layer 36B, for example, POM (polyacetal resin) can be used, and in particular, the inner layer 36A can be rotated by using a material having a lower coefficient of friction than the outer layer 36B. Resistance (axial loss) due to friction between the shaft 34 and the inner layer 36A is reduced, and the paper can be conveyed more smoothly.

  On the other hand, if the hardness of the outer peripheral surface of the outer layer 36B is too high, the contact area with the sheet recording surface becomes too small, and as a result, it becomes easy to form a belt-like roller mark (pressure contact mark). Therefore, it is desirable that the hardness of the outer peripheral surface of the outer layer 36B is as small as possible.

  Next, a mold structure when the conveyance driven roller 36 is molded will be described. FIGS. 4A and 4B show a cross section of a main part of a mold (not shown) used in an injection molding apparatus (not shown) capable of two-color molding. The mold for forming the transport driven roller 36 is for performing an upper mold (not shown) for the first color molding (primary molding) and a second color molding (secondary molding). And a movable lower mold (overall not shown) used in common in the first color molding and the second color molding.

  FIG. 4A shows a state in which the mold is clamped to perform the first color molding. In the figure, reference numeral 103 denotes a mold base belonging to the upper mold on the fixed side for performing the first color molding (primary molding). Reference numeral 110 denotes a mold base belonging to the lower mold on the movable side. Reference numeral 111 denotes a sleeve, and an eject rod 112 passes through the sleeve 111 so as to be slidable.

  A center pin 113 is slidably passed through the eject rod 112. The fitting convex portion 113a formed at the tip of the center pin 113 is fitted into the fitting concave portion 104a formed in the mold 104, and thereby the cavity 107 for forming the inner layer 36A is partitioned with high accuracy.

  A mold 104 is fitted into a mold base 103 constituting the upper mold, and a molten resin filling path 105 and a gate 106 are formed in the mold 104. The gate 106 is provided at a position where the end face 36e of the inner layer 36A is formed, and the filling path 105 extends straight along the substantially vertical direction toward the gate 106.

  When the first color molding (inner layer 36A) is performed by injecting molten resin in this state, the mold is opened, and the lower movable mold is rotated to perform the second color molding (secondary molding). It is arranged opposite to the upper die of the fixed side.

  FIG. 4B shows a state in which the mold is clamped to perform the second color molding. In the figure, reference numeral 203 denotes a mold base belonging to the upper mold on the fixed side for performing the second color molding (secondary molding). Is shown. In the figure, reference numeral 207 denotes a cavity for forming the outer layer 36B.

  In the upper mold used for the second color molding, a mold 204 is fitted into a mold base 203, and a molten resin filling path 205 and a gate 206 are formed in the mold 204. In the secondary molding die, the fitting convex portion 113 a formed at the tip of the center pin 113 is fitted into the fitting concave portion 204 a formed in the die 204.

  The filling path 205 extends toward the gate 206 so as to form a slight inclination angle with respect to the vertical direction, and the gate 206 is provided at a position facing the end surface 36e of the inner layer 36A. The flow then flows in the direction of the roller rotation axis.

  When the second color molding (outer layer 36B) is performed, the mold is opened, and the eject rod 112 is pushed upward to remove the molded product from the center pin 113 and take it out. In FIG. L indicates the parting line of the mold.

  In addition, the gate structure 106 when forming the inner layer 36A and the gate 206 when forming the outer layer 36B can be arranged inside the roller by the mold structure as described above, and the gate boss is the outer periphery of the transport driven roller 36. Neither occurs on the surface nor on the roller end face. In addition, by arranging the gates 106 and 206 not at the axial end of the transport driven roller 36 but at a position closer to the center, it is possible to prevent a large resin pressure from being generated at the roller end.

■■■ Assembly process of the transport driven roller ■■■
Next, with reference to FIGS. 5 to 7, the manufacturing process of the inkjet printer 1, in particular, from the forming process to the assembling process of the transport driven roller 36 will be described. The details of the primary molding (inner layer 36A) and secondary molding (outer layer 36B) shown in steps S101 and S102 of FIG. 5 are as described above, and the transport driven roller 36 is formed by the resin molding process described above.

  Here, in the molding process of the transport driven roller 36, even if the outer diameter of the straight portion S1 is uniformly formed in the roller length direction (left and right direction in FIG. 3) as described above, it is not necessarily uniform depending on the molding factor. Often not. For example, the outer diameter of one end (the outer diameter indicated by reference numeral D1 in FIG. 3A) is larger than the outer diameter of the other end (the outer diameter indicated by reference numeral D2 in FIG. 3A) (or Tend to be smaller).

  Since this tendency shows a certain tendency depending on the mold or material used, the outer diameters D1 and D2 are inspected by sampling for each molding lot (or for each mold used), and lot management is performed (step S103). ). It goes without saying that 100% inspection may be performed instead of sampling inspection.

  In this embodiment, since the shape of the roller is asymmetrical, it is not necessary to manage the orientation of the roller during component storage. However, when the shape of the roller is symmetrical, the molded product is ejected from the mold. After that, since the upper / lower relationship at the time of resin molding cannot be understood, it is preferable to manage the roller direction by performing some kind of marking or the like.

  In this embodiment, the designed roller outer diameter is set uniformly in the length direction of the straight portion S1 (in the design, the outer diameter D1 = D2). Although the diameters are different (outer diameter D1 ≠ D2), as described in detail below, the present invention uses the non-uniformity of the roller outer diameter. It may be set differently in the direction.

  Next, the roller is incorporated into the apparatus (step S104). In this assembling step, the pair of adjacent transport driven rollers 36 are arranged at predetermined positions so that the sides with the larger outer diameter (the outer diameter D1 side in this embodiment) face each other. In the present embodiment, the pair of transport driven rollers 36 that are arranged so that the sides having the larger outer diameters face each other are arranged at the most reference position side.

  6A shows a part of FIG. 2, FIG. 6B schematically shows (exaggeratedly) the shape and orientation of the transport driven roller, and the symbol L indicates the outside. The side with the larger diameter (the side of the outer diameter D1 in FIG. 3A) is shown, and the symbol S shows the side with the smaller outer diameter (the side of the outer diameter D2 in FIG. 3A).

  As shown in the figure, among a plurality of transport driven rollers 36, a pair of adjacent transport driven rollers 36A and 36B located closest to the reference position X1 is such that the large outer diameter side L faces each other, and the intermediate position X3 is set between the two adjacent ribs 51 and 52 constituting the first rib R1.

  The effect by this is as follows. That is, when recording on the first surface is performed, regular undulation (cockling) is formed on the sheet by the rib R1, but when the sheet on which recording has been performed on the first surface is reversed, The portion that was the cockling peak at the time of recording becomes the valley of the second surface, and conversely, the portion that was the cockling valley at the time of recording on the first surface becomes the peak of the second surface.

  That is, when recording on the second surface, the cockling has already been formed, and the valley of the second surface (crest of the first surface) is supported by the first rib R1, The mountain on the second surface (the valley on the first surface) is more prominently floated. As a result, the paper gap may become inappropriate and the recording quality may be degraded.

  FIG. 7 shows the relationship between the positions of the ribs 51 to 62 constituting the first rib R1 and the sheet floating (floating in the first rib R1 before recording on the second surface). Unlike the present embodiment, the sheet floating is shown when all the transport driven rollers 36 are arranged with the small outer diameter side S facing the reference position X1 side. As shown in the drawing, the sheet floating between the rib 51 and the rib 52 is large. It should be noted that the position where the sheet float increases depends on the apparatus configuration.

  On the other hand, by arranging the pair of adjacent transport driven rollers 36A and 36B such that the large outer diameter sides L face each other as in the present embodiment, the set of transport driven rollers 36A and 36B are used. In the transport region, the sheet transport direction is directed from the intermediate position X3 of the two rollers toward both outer sides as indicated by an arrow T.

  Thereby, in the said conveyance area | region, the tendency for a paper to be extended on the boundary of the intermediate position X3 is provided (extension effect), in other words, a wrinkle extension effect is acquired. By disposing the conveyance area where such an extension effect can be obtained at a predetermined position, that is, at a position where the sheet floating is remarkable, it is possible to suppress the sheet floating caused by the recording on the first surface.

  In this embodiment, the position where the sheet floats is prominent between the rib 51 and the rib 52, and therefore, a pair of transport driven rollers 36 (the transport driven rollers 36A, 36A, etc.) arranged so that the large outer diameter sides L face each other. 36B) is arranged between the rib 51 and the rib 52. Thereby, as shown by the solid line in FIG. 7, the sheet floating between the rib 51 and the rib 52 can be suppressed to an extremely small level. Further, the gap between the recording head 42 and the paper can be made as uniform as possible in the paper width direction.

  In the present embodiment, the other transport driven rollers 36C to 36F are all arranged such that the side L having the larger outer diameter faces the reference position X1 side (the lower diagram in FIG. 6). As a result, it is possible to prevent the sides S having a small outer diameter from being arranged to face each other, that is, to prevent the reverse action of the extension effect (the action that increases the sheet floating).

  8A to 8D show variations in which the combination of a pair of transport driven rollers 36 arranged so that the large outer diameter sides L face each other is changed. In any of these variations, since the sheet is provided with a tendency to extend at the intermediate position X3 of the pair of transport driven rollers 36 arranged so that the large outer diameter sides L face each other, Paper lift can be suppressed in the conveyance area by the roller.

  Here, in any of the variations shown in FIGS. 8A to 8D, the intermediate position X3 of the pair of adjacent transport driven rollers 36 arranged so that the large outer diameter sides L face each other is used as a boundary. The large side L of the conveyance driven roller 36 to be arranged on one side (for example, the right side) is arranged in the same direction. Further, the large side L of the conveyance driven roller 36 to be arranged on the other side (for example, the left side) is also arranged in the same direction.

  In other words, the rollers are arranged so that the directions of the rollers are symmetric with respect to the intermediate position X3. Thereby, the roller group by which the side S with a small outer diameter faces each other does not generate | occur | produce, and it can prevent that the reverse effect of the said extension effect arises.

  It should be noted that the sheet floating (dashed line in FIG. 7) when recording on the second surface is likely to become prominent when the interval between the ribs is increased. Therefore, in this embodiment, the large outer diameter sides L face each other. The intermediate position X3 of the transport driven roller 36 arranged at the position is set between two adjacent ribs having the largest arrangement interval. However, when the sheet floating at a predetermined location becomes large due to other factors, such an intermediate position X3 is set. If the intermediate position X3 is arranged at or near a predetermined location, it is possible to obtain a sheet lifting suppression effect at the predetermined location.

  The embodiment described above is an example, and various other modifications can be made. For example, if the configuration is such that a force is applied to the paper P toward both outsides in the paper width direction with the central position X3 as a boundary (for example, the arrow T shown in FIG. The above-described extension effect can be obtained.

  In the above embodiment, a pair of adjacent transport driven rollers 36 are arranged so that the large outer diameter sides L face each other, so that the sheet transport direction is 2 as indicated by an arrow T in FIG. It was made to skew diagonally from the intermediate position X3 of two rollers to the both outer directions.

  However, for example, by tilting the rotation shaft 34 of the transport driven roller 36 (tilting the rotation axis), it is possible to realize skew in the sheet transport direction as indicated by the arrow T in FIG. In this case, the outer diameter of the conveyance driven roller 36 may be uniform in the roller length direction.

  If the conveyance direction of the entire sheet is skewed due to the arrangement of the conveyance driven roller 36 as described above, all or a part of the rotation axis of the conveyance driven roller 36 may be canceled out. It may be set to tilt. Alternatively, the rotation axis of the transport driving roller 35 may be set to be inclined so as to cancel the skew.

DESCRIPTION OF SYMBOLS 1 Inkjet printer, 2 Feeding device, 4 Recording means, 5 Conveyance means, 6 Ejection means, 7 Inversion unit, 11 Paper cassette, 12 Separation slope, 16 Pickup roller, 17 Oscillation member, 18 Oscillation shaft, 20 Driven roller , 21 Separation means, 22 Separation roller, 23 Drive roller, 25 First intermediate feed section, 26 Drive roller, 27 Assist roller, 29 Drive roller, 31 Second intermediate feed section, 32 Drive roller, 33 Assist roller, 34 Rotating shaft , 35 Conveyance drive roller, 36 (36A-36B) Conveyance driven roller, 37 Upper guide member, 38 Coil spring, 39 Lower guide member, 40 Carriage, 41 Carriage guide shaft, 42 Recording head, 43 Auxiliary roller, 44 Discharge drive roller , 45 Emission driven low -, 46 Reverse roller, 47, 48 Assist roller, 49 frame, 51-63 rib (each rib of the first rib), R1 first rib, R2 second rib, R3 third rib, S1 (of the transport driven roller 36) ) Inner layer, S2 Outer layer (of transport driven roller 36), P recording paper, Q ink absorber

Claims (3)

Recording means for recording on a recording medium;
A plurality of first rollers provided at appropriate intervals along a direction intersecting with a conveyance direction of the recording medium, and a second roller for nipping the recording medium between the first roller and the first roller. A recording medium conveying means for conveying a recording medium to a recording position by the recording means by rotation of a roller and the second roller;
The recording medium is reversed so that the second surface opposite to the first surface of the recording medium on which recording is performed by the recording means is opposed to the recording means, and the recording medium is conveyed to the recording medium conveying means side. A recording medium reversing means for sending a double-sided recording apparatus,
An inspection step of inspecting which side is larger with respect to the outer diameter of both ends of the first roller in the roller length direction;
A roller assembling step of arranging at least one pair of adjacent first rollers among the plurality of first rollers arranged in a predetermined position such that the outer diameter sides of the roller outer peripheral surfaces face each other in the roller length direction;
A method for manufacturing a double-sided recording apparatus, comprising: 2. The method for manufacturing a double-sided recording apparatus according to claim 1, wherein the double-sided recording apparatus is disposed so as to face the recording head, and a rib that supports the recording medium is appropriately disposed along a direction intersecting a conveyance direction of the recording medium. A plurality of recording medium guide members provided at intervals of
In the roller assembly step, an intermediate position of the at least one pair of adjacent first rollers in a direction intersecting the transport direction is set between two adjacent ribs having the largest arrangement interval.
A method for manufacturing a double-sided recording apparatus. 3. The method for manufacturing a double-sided recording apparatus according to claim 1, wherein in the roller assembling step, the first roller to be arranged on one side with an intermediate position between the pair of adjacent first rollers as a boundary. All of the large outer diameter sides are arranged in the same direction, and the large outer diameter side of the first roller to be arranged on the other side is also arranged in the same direction.
A method for manufacturing a double-sided recording apparatus.

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