JP4577519B2 - RECORDED MEDIUM CONVEYING DEVICE, RECORDING DEVICE - Google Patents

Description

  The present invention relates to a recording medium transport apparatus that transports a recording medium in a recording apparatus, and a recording apparatus including the recording medium transport apparatus.

  An example of the recording apparatus or the liquid ejecting apparatus is an ink jet printer. An ink jet printer supports a recording paper from below at a position facing an ink jet recording head that discharges ink (liquid) onto a recording paper as a recording medium (jetting medium), and thereby a gap between the ink jet recording head and the recording paper. A platen (recording medium guide member) is provided.

  A plurality of ribs extending in the sub-scanning direction are provided on the surface of the platen facing the ink jet recording head at a predetermined interval in the main scanning direction. This is to form a wavy state (so-called “cockling state”) having a constant amplitude on a recording sheet that swells by absorbing ink, thereby making the distance between the recording surface and the ink jet recording head as uniform as possible. It is. Patent Document 1 describes an ink jet recording apparatus that can switch the surface state of a recording medium supporting means having such a rib according to the type of paper by a movable rib.

Japanese Patent Laid-Open No. 2004-167738

  By the way, the sheet conveying means provided on the upstream side of the platen conveys the recording sheet while pressing the recording sheet toward the platen. This is to prevent the recording paper from lifting from the platen, to prevent head rubbing, and to prevent a change in the gap between the recording head and the recording paper, thereby preventing a decrease in recording quality. Accordingly, a frictional force is generated between the recording paper and the rib.

  On the other hand, the ribs need to be arranged in accordance with the cockling cycle of the recording paper, and in order to prevent the both sides of the recording paper from falling, they are arranged slightly inside both sides of the recording paper, It is necessary to support the side from below. Therefore, there is a restriction on the arrangement position of the ribs, and the ribs cannot be arranged freely.

Here, a frictional force is generated between the recording paper and the rib, but there are cases where the arrangement position and / or the number of the ribs are asymmetric with respect to the center of the recording paper of a certain size in the main scanning direction. Therefore, there is a risk that the balance of the frictional force will be lost on the left and right, resulting in skew.
Further, there may be a skew due to a difference between the left and right outer diameters of a sheet feeding roller as a sheet conveying means provided on the upstream side of the platen, or a decrease in accuracy during assembly.

On the other hand, the skew caused by the sheet conveying means provided on the upstream side of the platen as described above and the skew caused by the platen itself are short or almost free from the skew because the distance to the recording head is short. It is impossible to provide a correction means.
Accordingly, the present invention has been made in view of such problems, and an object thereof is to obtain a suitable recording quality by preventing skew by using a guide member that supports a recording sheet.

  In order to solve the above-described problems, a first aspect of the present invention includes a conveying unit that conveys a recording medium, and a downstream side of the conveying unit that supports the recording medium and the recording medium on the downstream side. A recording medium conveyance device including a recording medium guide member for guiding the recording medium, wherein the recording medium guide member includes a plurality of ribs extending in the sub-scanning direction at appropriate intervals in the main scanning direction. The arrangement position and / or number of the ribs with respect to the recording medium of a predetermined size is asymmetric with respect to the center position in the main scanning direction of the recording medium of the predetermined size, and The center of the recording medium of the predetermined size in the main scanning direction when the conveying force applied to the recording medium of the predetermined size acts evenly on the center position of the recording medium of the predetermined size in the main scanning direction. 1 digit from position The frictional force between the rib arranged in the area of the recording medium and the recording medium is arranged in the area on the 80th digit side from the center position and the force to rotate the recording medium in a plane parallel to the transport direction. The height of the rib that supports the recording medium of the predetermined size so that the frictional force between the rib and the recording medium is balanced with the force that rotates the recording medium in a plane parallel to the transport direction. Is formed non-uniformly in the main scanning direction.

  According to this aspect, the frictional force between the rib disposed in the region on the one-digit side of the center position in the main scanning direction of the recording medium having a predetermined size and the recording medium is parallel to the recording medium in the transport direction. And the frictional force between the rib arranged in the region 80 digits from the center position and the recording medium tries to rotate the recording medium in a plane parallel to the transport direction. The height of the ribs that support the recording medium of a predetermined size is formed non-uniformly in the main scanning direction so that the force balances with the force. Can be prevented at low cost without using any components.

  According to a second aspect of the present invention, there is provided a conveyance unit that conveys a recording medium, and a recording medium guide member that is provided downstream of the conveyance unit and supports the recording medium and guides the recording medium downstream. The recording medium guide member is provided with a plurality of ribs extending in the sub-scanning direction at appropriate intervals in the main scanning direction, so that a recording medium of a predetermined size is recorded. When the transport force applied to the recording medium of the predetermined size by the transport means acts on the medium non-uniformly with respect to the center position in the main scanning direction of the recording medium of the predetermined size, the transport force Force to rotate the recording medium in a plane parallel to the transport direction between the rib and the recording medium arranged in the region one digit side from the center position in the main scanning direction of the recording medium of the predetermined size. The frictional force between the recording media The force to rotate on the parallel plane and the frictional force between the ribs arranged in the area 80 digits from the center position and the recording medium rotate the recording medium on the plane parallel to the transport direction. The height of the rib supporting the recording medium of the predetermined size is formed non-uniformly in the main scanning direction so as to cancel out by the resultant force.

  According to this aspect, the transporting force when transporting the recording medium is less than the center position in the main scanning direction of the recording medium of a predetermined size by the force to rotate the recording medium on a plane parallel to the transporting direction. The frictional force between the rib arranged in the spar-side region and the recording medium is arranged to be in a region where the recording medium is rotated on a plane parallel to the transport direction and the 80-sigma side from the center position. The height of the ribs in the main scanning direction is non-linear so that the frictional force between the formed rib and the recording medium cancels out by the resultant force of the force that rotates the recording medium in a plane parallel to the transport direction. Since it is uniformly formed, the skew tendency generated by the conveying means can be corrected at a low cost without using any special component.

  According to a third aspect of the present invention, there is provided a conveying unit that conveys a recording medium, and a recording medium guide member that is provided downstream of the conveying unit and supports the recording medium and guides the recording medium downstream. The recording medium guide member is provided with a plurality of ribs extending in the sub-scanning direction at appropriate intervals in the main scanning direction, so that a recording medium of a predetermined size is recorded. With respect to the medium, the arrangement position and / or the number of the ribs are asymmetric with respect to the central position in the main scanning direction of the recording medium of the predetermined size, and the recording means has the recording medium of the predetermined size. When the applied conveying force acts evenly on the central position in the main scanning direction of the recording medium of the predetermined size, the feeding force is applied to an area one digit side from the central position in the main scanning direction of the recording medium of the predetermined size. With the arranged ribs The frictional force between the recording medium and the recording medium causes a force that causes the recording medium to rotate on a plane parallel to the transport direction, and the rib disposed in the region on the 80-digit side from the center position and the recording medium. Some of the plurality of ribs that support the recording medium of the predetermined size are recorded so that the frictional force is balanced with the force that rotates the recording medium in a plane parallel to the transport direction. It is provided so as to be displaceable in a direction that advances and retreats with respect to the medium, and is provided in a state of being urged toward the recording medium by the urging means.

  According to this aspect, the frictional force between the rib disposed in the region on the one-digit side of the center position in the main scanning direction of the recording medium having a predetermined size and the recording medium is parallel to the recording medium in the transport direction. And the frictional force between the rib arranged in the region 80 digits from the center position and the recording medium tries to rotate the recording medium on a plane parallel to the transport direction. In order to balance the force, some of the plurality of ribs that support the recording medium of a predetermined size are provided so as to be displaceable in a direction to advance and retreat with respect to the recording medium, and the recording medium by the biasing means Therefore, it is possible to prevent the occurrence of skew due to the recording medium guide member.

  In addition, the frictional force between the recording medium having high rigidity and the ribs tends to increase, but some of the plurality of ribs that support the recording medium of a predetermined size may be against the recording medium. Since it is provided so as to be displaceable in the advancing and retreating direction and is urged toward the recording medium by the urging means, the above-mentioned displaceable rib is used when conveying a recording medium having high rigidity. It is possible to suppress an increase in frictional force generated between the recording medium and the rib due to the sinking.

  According to a fourth aspect of the present invention, there is provided a conveying unit that conveys a recording medium, and a recording medium guide member that is provided downstream of the conveying unit and supports the recording medium and guides the recording medium downstream. A plurality of ribs extending in the sub-scanning direction at appropriate intervals in the main-scanning direction. When the conveyance force applied to the recording medium of a predetermined size acts non-uniformly with respect to the central position in the main scanning direction of the recording medium of the predetermined size, the conveyance force is parallel to the recording medium in the conveyance direction. The friction force between the rib and the recording medium disposed in the region one digit side from the center position in the main scanning direction of the recording medium of the predetermined size is applied to the recording medium. Trying to rotate on a plane parallel to the transport direction The frictional force between the rib arranged in the region 80 digits from the center position and the recording medium cancels out by the resultant force of the recording medium rotating on a plane parallel to the transport direction. Similarly, some of the plurality of ribs that support the recording medium of the predetermined size are provided so as to be displaceable in a direction to advance and retreat with respect to the recording medium and are directed toward the recording medium by the urging means. It is provided in an energized state.

  According to this aspect, the transporting force when transporting the recording medium is less than the center position in the main scanning direction of the recording medium of a predetermined size by the force to rotate the recording medium on a plane parallel to the transporting direction. The frictional force between the rib arranged in the spar-side region and the recording medium is arranged to be in a region where the recording medium is rotated on a plane parallel to the transport direction and the 80-sigma side from the center position. A plurality of media that support a recording medium of a predetermined size so that the frictional force between the formed rib and the recording medium cancels out by the resultant force of the force that rotates the recording medium in a plane parallel to the transport direction. Some of the ribs are provided so as to be displaceable in a direction to advance and retreat with respect to the recording medium, and are provided in a state of being urged toward the recording medium by the urging means. Correct skew caused by transport means It is possible.

  In addition, the frictional force between the recording medium having high rigidity and the ribs tends to increase, but some of the plurality of ribs that support the recording medium of a predetermined size may be against the recording medium. Since it is provided so as to be displaceable in the advancing and retreating direction and is urged toward the recording medium by the urging means, the above-mentioned displaceable rib is used when conveying a recording medium having high rigidity. It is possible to suppress an increase in frictional force generated between the recording medium and the rib due to the sinking.

  According to a fifth aspect of the present invention, there is provided a recording apparatus comprising a recording head for recording on a recording medium, comprising the recording medium guide apparatus according to any one of the first to fourth aspects. It is characterized by being. According to this aspect, in the recording apparatus, it is possible to obtain the same operational effects as any of the first to fourth aspects.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 8. Here, FIG. 1 is an external perspective view of the main body of the printer 1 (with the outer case removed), FIG. 2 is a cross-sectional side view of the same, FIG. 3 is a side view of the transport device 10, and FIGS. FIG. FIGS. 6A and 6B are side views of a transfer apparatus 10 ′ according to another embodiment, and FIGS. 7 and 8 are plan views thereof.

  Hereinafter, an outline of an ink jet printer (hereinafter referred to as “printer”) 1 as an example of a recording apparatus or a liquid ejecting apparatus according to the present invention will be described first with reference to FIGS. 1 and 2. In the following, the left direction in FIG. 2 (the front side of the printer) is referred to as “downstream side” of the sheet conveyance path, and the right direction in FIG. 2 is referred to as “upstream side”.

  The printer 1 includes a feeding device 2 capable of setting a recording sheet (mainly cut sheet paper: hereinafter referred to as “sheet P”) as an example of “recording medium” and “ejection medium” in an inclined posture at the rear part, The paper P is fed from the feeding device 2 toward the conveying means 4 on the downstream side. The fed paper P is transported (sub-scanned) by the transport unit 4 to the downstream recording head 36 (recording unit 3), and recording is performed. Then, the paper P on which recording has been performed by the recording head 36 is discharged to the front of the apparatus by the discharge means 5 on the downstream side.

Hereinafter, components on the paper conveyance path of the printer 1 will be described in more detail. The feeding device 2 includes a hopper 11, a feeding roller 12, a retard roller 13, a return lever 14, and other components not shown.
The hopper 11 is formed of a plate-like body, and is provided so as to be able to swing around an upper swing fulcrum 11a. By swinging, the paper P supported in an inclined posture on the hopper 11 is pressed against the feeding roller 12. The pressure contact posture to be switched and the separation posture to be separated from the feeding roller 12 are switched. The feeding roller 12 has a substantially D shape when viewed from the side, and feeds the uppermost sheet P pressed by the arc portion to the downstream side.

  The retard roller 13 is provided so as to be able to press-contact with the arc portion of the feeding roller 12 and is provided with a predetermined rotational resistance (torque). If only a plurality of sheets of paper P exist between the feed roller 12 and the retard roller 13, the paper does not rotate. In this state, the paper P is prevented from being double fed. The return lever 14 is provided so as to be swingable when the paper P feeding path is viewed from the side. By swinging, the return lever 14 returns the succeeding and subsequent sheets P to the hopper 11.

Next, a detecting means (not shown) for detecting the passage of the paper P is formed between the feeding device 2 and the transporting means 4, and a feeding posture of the paper P is formed and the paper P feeding roller 12 is formed. A guide roller 26 is provided to prevent the contact load to reduce the conveyance load.
The transport means 4 includes a transport drive roller 30 that is rotationally driven by a motor (not shown), and a transport driven roller 31 that is driven to rotate while being pressed against the transport drive roller 30. The transport driving roller 30 is provided with an adhesion layer formed by substantially uniformly dispersing wear-resistant particles on the outer peripheral surface of a metal shaft extending in the paper width direction (main scanning direction), and the transport driven roller 31 has an outer peripheral surface on an elastomer. A plurality of (six in this embodiment) are arranged in the axial direction of the conveyance drive roller 30.

  In the present embodiment, two transport driven rollers 31 are pivotally supported at the downstream end of the paper guide upper 24 so as to be freely rotatable. In the present embodiment, three of the paper guide upper rollers 31 are arranged in parallel in the paper width direction. Is done. The top 24 of the paper guide is provided so that the shaft 24a is pivotally supported by the main frame 7 so as to be swingable about the shaft 24a as seen from the side of the paper transport path, and the transport driven roller 31 is provided by the coil spring 25. It is urged in a direction in which it comes into pressure contact with the conveyance drive roller 30.

The paper P that has reached the transport means 4 is sub-scanned and sent downstream by the transport drive roller 30 rotating while being nipped by the transport drive roller 30 and the transport driven roller 31.
An ink jet recording head (hereinafter referred to as “recording head”) 36 and a paper guide 50 disposed to face the recording head 36 are provided on the downstream side of the transport driving roller 30 and the transport driven roller 31. . The recording head 36 is provided at the bottom of the carriage 33. The carriage 33 is driven to reciprocate in the main scanning direction by a drive motor (not shown) while being guided by a carriage guide shaft 34 extending in the main scanning direction. The carriage 33 is mounted with independent ink cartridges (not shown) for each of a plurality of colors, and supplies ink to the recording head 36.

  The paper guide 50 that defines the distance between the paper P and the recording head 36 includes ribs 51, 52, and 53 that extend in the sub-scanning direction at predetermined intervals from the upstream side on the surface facing the recording head 36. A plurality are provided at appropriate intervals in the main scanning direction. The paper P is pressed against the rib 51 by the transport driving roller 30 and the transport driven roller 31 provided on the upstream side of the paper guide 50 and is supported by the ribs 51, 52, 53 while being downstream by the paper guide 50. It is conveyed to the side.

  The angle α shown in FIG. 3 indicates an angle formed by a straight line passing through the rotation axis of the conveyance drive roller 30 and the rotation axis of the conveyance driven roller 31 and a straight line parallel to the direction of gravity. By providing the angle α, the sheet feeding direction (tangent line at the nip point of both rollers) by the conveyance driving roller 30 and the conveyance driven roller 31 is directed toward the rib 51 of the sheet guide 50 when the sheet conveyance path is viewed from the side. It is configured. The transport unit 4 and the paper guide 50 constitute the transport device 10 as the “recording medium transport device” and the “ejected medium transport device” according to the present invention.

  In FIG. 3, a symbol h indicates a height difference (a height difference in the vertical direction) between the nip point between the transport driving roller 30 and the transport driven roller 31 and the top of the rib 51. In the present embodiment, the paper transport direction is the left direction in FIG. 3 and is a direction orthogonal to the direction of gravity. Therefore, as the angle α increases, the sheet P is further pressed against the rib 51, and the conveyance driving roller 30 and the conveyance driven roller 31 decrease as the protrusion amount (projection height) h of the rib 51 to the sheet P decreases. Since the amount of deformation of the sheet before and after the nip point increases, the sheet P is further pressed against the rib 51.

  Subsequently, referring back to FIG. 2, an auxiliary roller 43 and a discharge unit 5 are provided on the downstream side of the recording head 36. The auxiliary roller 43 is provided on the paper conveyance path from the area where the recording head 36 and the paper guide 50 face each other to the discharge means 5 so as to be driven and rotated in contact with the recording surface of the paper P. The function of preventing the lift from 50 and maintaining the distance between the paper P and the recording head 36 constant is achieved.

  The discharge means 5 includes a discharge drive roller 41 that is rotationally driven by a motor (not shown), and a discharge driven roller 42 that is driven to rotate in contact with the discharge drive roller 41. When the discharge drive roller 41 is rotationally driven while being nipped by the discharge drive roller 41 and the discharge driven roller 42, the discharge drive roller 41 is discharged toward the front of the apparatus (not shown).

The above is the general configuration of the printer 1, and the conveyance device 10, particularly the paper guide 50, will be described in detail with reference to FIGS. 4 and 5.
4 and 5, a plurality of the paper guide upper 24, the transport driven roller 31, the rib 51, and the rib 52 provided in the main scanning direction (left and right direction in FIGS. 4 and FIG. 5, the symbols A, B,...

In FIG. 4, reference symbol P ₁ indicates a sheet of a predetermined size, and reference symbol C ₁ indicates a line (center line) indicating the center position of the sheet P _{1 in} the main scanning direction. Reference numerals F ₁ and F ₂ indicate transport forces applied to the paper sheet P ₁ by the transport driven rollers 31A and 31B, respectively. Reference numerals T ₁ and T ₂ indicate between the ribs 51A and 51B and the paper sheet P ₁ , respectively. The frictional force generated at (becomes a transport load) is shown.

In FIG. 4, the conveying forces F ₁ and F ₂ operate symmetrically with respect to the center line C ₁ (b ₁ = b ₂ ) and have the same size. In other words, the transport force applied to the paper P ₁ by the transport unit 4 acts evenly on the center line C ₁ , so that no skew is generated due to the transport unit 4.

Further, the frictional forces T ₁ and T ₂ also act at symmetrical positions (a ₁ = a ₂ ) and have the same size (that the rib height is the same). Thus the surface parallel frictional force T ₁ is the paper conveyance direction the paper P ₁ (i.e., the recording surface parallel to the plane) and force to rotate in, also the frictional force T ₂ and the sheet conveying direction the paper P ₁ The force to rotate on the parallel plane is balanced (the directions of the forces to rotate the paper are opposite to each other and have the same magnitude). Therefore, no skew is caused by the paper guide 50. By the above, when conveying the paper sheet P ₁ is in a state that does not cause skew tendency to the sheet P _1.

Next, in FIG. 5, reference symbol P ₂ indicates a sheet having a size larger than that of the sheet P ₁ , and reference symbol C ₂ indicates a line (center line) indicating the center position of the sheet P _{2 in} the main scanning direction. . Since all sizes of paper are transported with reference to the 1st digit side, when the paper size becomes larger, the receiving force is further received from the transport driven roller 31 located on the 80th digit side, and the rib 51 located on the 80th digit side. A frictional force is generated between When the paper _{P 2} shown in FIG. 5, unlike the sheet _{P 1,} ribs 51C which is located 80 digit side, while being further supported by 52C, further receives a conveying force _{F 3} by the conveying driven roller 31C.

Here, in the example of FIG. 5, the transport force F ₂ is exactly at the position of the center line C ₂ , and the transport forces F ₁ and F ₃ act at positions symmetrical to the center line C ₂ (b ₁ = b ₂ ). Further, the frictional forces T ₁ and T ₃ also act at positions symmetrical with respect to the center line C ₂ (a ₁ = a ₂ ). However, the frictional force T _2, together with the acting position from the center line C ₂ 80-digit side, the frictional force which forms the frictional force T ₂ and symmetrical relationship is not present. That for the sheet P _2, the arrangement number of the ribs 51 is asymmetrical with respect to the center line C _2.

If the frictional force T ₁ = T ₂ = T ₃ is assumed here, the frictional force (T ₁ ) between the rib disposed in the region one digit side from the center line C ₂ and the paper P ₂ is the paper P _2. and force to rotate in a plane parallel to the sheet conveying direction, the frictional force between the rib and the sheet P ₂ disposed likewise 80-digit side region _{(T 2,} T ₃₎ is a sheet P ₂ and force to rotate in a plane parallel to the sheet conveying direction, are no longer balanced, whereby the sheet P ₂ skew tendency due to the paper guide 50 is generated.

Therefore, the height of the rib 51C is set lower than the height of the ribs 51A and 51B so as not to cause such a skew tendency. That is, the frictional force T ₃ is configured to be smaller than the frictional forces T ₁ and T ₂ . Note that one digit side of the ribs 51A, by changing the height of 51B, as it means that the skew tendency occurs in a small sheet P ₁ in size, for optimizing the rib height is less in size The paper guide 50 is integrally formed of, for example, a resin material after the final rib height is determined in this manner.

By the above, the rib height by (dimension in FIG. 3 h) is non-uniformly formed in the main scanning direction, the center line C ₂ is arranged in the region of one digit side ribs (51A) and the paper P ₂ between the force of friction force _{(T 1)} is to rotate the sheet _{P 2,} also the center line _{C 2} from 80 column side region arranged ribs (51B, 51C) and the paper _{P 2} between the The frictional force (T ₂ , T ₃ ) balances with the force to rotate the paper P ₂ , thereby causing a skew caused by the paper guide 50 for both the paper P ₁ and P _2. You can make it not.

  Incidentally, photographic paper (glossy paper) manufactured by Seiko Epson Corporation was used, and in FIG. 3, α = 13 °, h = 0.5 mm, L (the upstream end of the top of the rib 51 to the transport driving roller 30 and the transport driven roller) When the rib height (dimension h) is changed by 25 μm under the condition that the nip point distance with the roller 31 is 12 mm and the circumferential length of the conveyance drive roller 30 is 1 inch, the paper feed amount of 1 inch is about 1 μm. A change in transport amount was obtained. Therefore, the rib height can be determined based on such experimental results. However, since the gap between the recording head 36 and the recording surface is changed by changing the rib height, the amount of change in the rib height is preferably 0.1 mm or less.

By the way, in the above example, the conveying forces F ₁ and F ₂ act at symmetrical positions (b ₁ = b ₂ ) and have the same magnitude with respect to the center lines C ₁ and C ₂ , but act at asymmetric positions. In some cases (b ₁ ≠ b ₂ ), or in a symmetric position but different in size, or in an asymmetrical position and different in size. That is, the paper transport force by the transport driving roller 30 and the transport driven roller 31 does not act on the center lines C ₁ and C ₂ in an uneven manner, that is, the paper transport force rotates on a plane parallel to the paper transport direction. By trying to do so, a skew tendency may occur in the paper.

  Even in such a case, the sheet conveying force exerts a force to rotate the sheet on a plane parallel to the conveying direction between the rib and the sheet disposed in the region one digit side from the center position in the main scanning direction of the sheet. The friction force between the ribs and the force between the ribs arranged in the 80-digit area and the paper force cancels out by the combined force of the force to rotate the paper and the force to rotate the paper. If the rib height is formed non-uniformly in the main scanning direction, the occurrence of skew can be prevented as a result.

An embodiment in such a case will be described with reference to FIGS.
FIG sheet P ₂ shown in 7 is identical to the sheet P ₂ shown in FIG. 5, but the sheet P _{2 'is} shown in FIG. 8 is a sheet P ₂ and the size are the same as shown in FIG. 5, the sheet P ₂ It is stronger than that (high rigidity).

7, 8, the sheet conveying force _{F 2} is on the center line _{C 2} of the sheet _{P 2} is, conveying force F1, F3 with respect to the center line _{C 2} is in asymmetrical positions _{(b 1} ≠ _{b 2} ). Accordingly, the sheet conveying force tries to rotate the sheet on a plane parallel to the conveying direction, thereby causing the sheet to have a skew tendency.

The frictional forces T ₁ and T ₃ act at positions symmetrical to the center line C ₂ (a ₁ = a ₂ ), but the friction force T _{2 is} about 80 digits from the center line C _2. together acting position, the frictional force which forms the frictional force T ₂ and symmetrical relationship is not present.
Therefore the height of the ribs 61B in the example of FIG. 7, i.e. to adjust the frictional force T _2, thereby (exclusively F ₁ and F ₃ in the example of FIG. ₇₎ is a surface parallel to the conveying direction the paper P ₂ sheet conveying force in the force for rotating constitute as canceled by the friction force T _2.

Here, in the present embodiment, the rib 61B is provided so as to be displaceable in a forward / backward direction (vertical direction in FIG. 6) with respect to the paper and is provided in a state of being urged toward the paper by the urging means. Yes. FIG. 6 shows this state, and reference numeral 64 indicates a spring as the biasing means. Since the sheet P ₂ is to be pressed against the sheet guide 60 by the transport driving roller 30 and the transport driven roller 31, whereby the rib 61B is sinking, rib height is given as lower.

Hereinafter, the function and effect of the rib 61B will be described. As the rigidity of the paper increases, the frictional forces T ₁ and T ₃ shown in FIG. 7 increase as shown in FIG. Here, even if the frictional forces T ₁ and T ₃ increase, both are in a symmetric position with respect to the center line C ₂ , so the paper P ₂ is rotated by the increase of the frictional forces T ₁ and T _3. There is no trend. Therefore, since the sheet conveying force (F ₁ and F ₃ ) cancels out the force to rotate the sheet P ₂ on the plane parallel to the conveying direction by the frictional force T ₂ , the frictional force is increased even if the sheet rigidity is increased. It is necessary to maintain T _{2 so that it} is substantially constant. Even paper stiffness is changed, the change is not in the conveying force _F 1 to F _3.

Here, assuming that the ribs 61B are provided in a fixed state, when the sheet P ₂ having high rigidity is conveyed strong frictional force acts between the paper P ₂ and the rib 61B, namely the frictional force T ₂ will increase. However, the rib 61B is a retractable relative to the sheet P _2, when the paper stiffness is low, small sinking amount of the rib 61B (FIG. 6 (A)), when the high sheet stiffness, The sinking amount of the rib 61B increases (FIG. 6B).
Accordingly therefore, regardless of the sheet rigidity, it is possible to maintain the frictional force T ₂ which occurs in the ribs 61B substantially constant, i.e. regardless of the paper stiffness, and it is possible to prevent the occurrence of skew.

In the embodiment described above, an example in which the present invention is applied to an ink jet printer as an example of a recording apparatus has been described. However, it is needless to say that the present invention is not limited to a recording apparatus and can be generally used for a liquid ejecting apparatus.
Here, the liquid ejecting apparatus uses an ink jet recording head, and is not limited to a recording apparatus such as a printer, a copying machine, and a facsimile machine that discharges ink from the recording head to perform recording on a recording medium. And a device that ejects a liquid corresponding to the application from a liquid ejecting head corresponding to the ink jet recording head to an ejected medium corresponding to a recording medium, and adheres the liquid to the ejected medium. .

  In addition to the recording head, as a liquid ejecting head, a color material ejecting head used for manufacturing a color filter such as a liquid crystal display, and an electrode material (conductive paste) used for forming an electrode such as an organic EL display or a surface emitting display (FED) Examples thereof include an ejection head, a bioorganic matter ejection head used for biochip production, and a sample ejection head as a precision pipette.

1 is an external perspective view of an apparatus main body of a printer according to the present invention. FIG. 3 is a side sectional view of the main body of the printer according to the present invention. The side view of a conveying apparatus. The top view of a conveying apparatus. The top view of a conveying apparatus. (A) (B) Both are side views of the conveying apparatus which concerns on other embodiment. The top view of the conveying apparatus which concerns on other embodiment. The top view of the conveying apparatus which concerns on other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer, 2 Feeding device, 3 Recording means, 4 Conveying means, 5 Discharge means, 7 Main frame, 7a Side frame, 8 Intermediate frame, 10 Conveying apparatus, 11 Hopper, 12 Feeding roller, 13 Retard roller, 14 Return lever, 24 on paper guide, 25 coil spring, 26 guide roller, 30 transport drive roller, 31 transport driven roller, 33 carriage, 34 carriage guide shaft, 36 recording head, 41 discharge drive roller, 42 discharge driven roller, 43 guide Roller, 50 paper guide, 51, 52, 53 rib, P recording paper,

Claims (5)

Conveying means for conveying a recording medium;
A recording medium conveying apparatus provided on the downstream side of the conveying means, and a recording medium guiding member that supports the recording medium and guides the recording medium to the downstream side,
Wherein the recording medium guide member, Li blanking is arranged at the other end side of the region of from the center position between one end side of the region of the center position of the recording medium of a predetermined size in the main scanning direction And
For the recording medium of the predetermined size, the arrangement position or / and the number of the ribs are asymmetric with respect to the central position in the main scanning direction of the recording medium of the predetermined size,
When the transport force applied to the recording medium of the predetermined size by the transporting means acts equally on the center position in the main scanning direction of the recording medium of the predetermined size, it is closer to the end on the one side. The friction force between the rib arranged in the area and the recording medium causes the force to rotate the recording medium in a plane parallel to the transport direction, and the rib arranged in the area near the end on the other side. The force that causes the frictional force between the recording medium and the recording medium to rotate the recording medium in a plane parallel to the transport direction is balanced by the height of each rib in the main scanning direction .
A recording medium conveying apparatus characterized by the above. Conveying means for conveying a recording medium;
A recording medium conveying apparatus provided on the downstream side of the conveying means, and a recording medium guiding member that supports the recording medium and guides the recording medium to the downstream side,
Wherein the recording medium guide member, Li blanking is arranged at the other end side of the region of from the center position between one end side of the region of the center position of the recording medium of a predetermined size in the main scanning direction And
When the transport force applied to the recording medium of the predetermined size by the transporting means acts non-uniformly on the center position in the main scanning direction of the recording medium of the predetermined size, it is closer to the end on the one side. The frictional force between the rib arranged in the area and the recording medium is arranged in the area near the end on the other side , and the force to rotate the recording medium in a plane parallel to the transport direction. The resultant force of the friction force between the rib and the recording medium and the force to rotate the recording medium in a plane parallel to the transport direction is determined by the height of each rib in the main scanning direction. Counteract the force to rotate the recording medium in a plane parallel to the transport direction ,
A recording medium conveying apparatus characterized by the above. Conveying means for conveying a recording medium;
A recording medium conveying apparatus provided on the downstream side of the conveying means, and a recording medium guiding member that supports the recording medium and guides the recording medium to the downstream side,
Wherein the recording medium guide member, Li blanking is arranged at the other end side of the region of from the center position between one end side of the region of the center position of the recording medium of a predetermined size in the main scanning direction And
For the recording medium of a predetermined size, the arrangement position or / and the number of the ribs are asymmetric with respect to the center position in the main scanning direction of the recording medium of the predetermined size,
When the transport force applied to the recording medium of the predetermined size by the transporting means acts equally on the center position in the main scanning direction of the recording medium of the predetermined size, it is closer to the end on the one side. The friction force between the rib arranged in the area and the recording medium causes the force to rotate the recording medium in a plane parallel to the transport direction, and the rib arranged in the area near the end on the other side. Some of the ribs are applied to the recording medium so that the frictional force between the recording medium and the recording medium balances with the force to rotate the recording medium in a plane parallel to the transport direction. Are provided so as to be displaceable in the advancing and retreating direction, and are provided in a state of being urged toward the recording medium by the urging means,
A recording medium conveying apparatus characterized by the above. Conveying means for conveying a recording medium;
A recording medium conveying apparatus provided on the downstream side of the conveying means, and a recording medium guiding member that supports the recording medium and guides the recording medium to the downstream side,
Wherein the recording medium guide member, Li blanking is arranged at the other end side of the region of from the center position between one end side of the region of the center position of the recording medium of a predetermined size in the main scanning direction And
When the transport force applied to the recording medium of the predetermined size by the transporting means acts non-uniformly on the center position in the main scanning direction of the recording medium of the predetermined size, it is closer to the end on the one side. The frictional force between the rib arranged in the area and the recording medium is arranged in the area near the end on the other side , and the force to rotate the recording medium in a plane parallel to the transport direction. The resultant force of the friction force between the rib and the recording medium to rotate the recording medium in a plane parallel to the transport direction is the resultant force of the transport force on the surface parallel to the recording direction. Some of the ribs are provided so as to be displaceable in a direction to advance and retreat with respect to the recording medium so as to cancel the force to rotate, and are urged toward the recording medium by the urging means. Provided in the state,
A recording medium conveying apparatus characterized by the above. A recording apparatus comprising a recording head for recording on a recording medium, comprising the recording medium conveying apparatus according to any one of claims 1 to 4.
A recording apparatus.

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