JP2008074612A - Recording medium conveying apparatus, recording apparatus, and liquid ejecting apparatus - Google Patents

Abstract

In a configuration in which a plurality of transport driven rollers are provided on one holding member, the contact pressure with respect to a recording sheet becomes more uniform between the respective transport driven rollers, and recording on the outer peripheral surface of a single transport driven roller is also possible. Provided is a conveying device in which the contact pressure with respect to a sheet is more uniform.
A shaft body passes through a plurality of transport driven rollers that are driven to rotate while being in contact with a transport drive roller that is rotationally driven, and the shaft body is held on a paper guide. . The shaft body 34 is urged toward the conveyance driving roller 41 by the coil springs 32 and 33, and the urging force is configured to act on both sides of the plurality of conveyance driven rollers 41.
[Selection] Figure 12

Description

The present invention relates to a conveyance drive roller that is rotationally driven, a conveyance driven roller that is elastically contacted with the conveyance drive roller, and a conveyance driven roller that rotates following the conveyance drive roller, and a recording medium conveyance device that conveys a recording medium. The present invention also relates to 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.

One of recording apparatuses or liquid ejecting apparatuses is an ink jet printer. The ink jet printer includes a conveyance roller that conveys a recording medium as an example of a recording medium or an ejection medium on the upstream side of an ink jet recording head that ejects ink. The transport roller is composed of a transport drive roller that is rotationally driven, and a pair of transport driven rollers that are driven to rotate following the transport drive roller. The transport driven roller is held by a holding member (holder) so as to be freely rotatable, and is biased toward the transport driving roller by a biasing means such as a torsion coil spring that applies a biasing force to the holding member. It is provided in the state (for example, refer to Patent Document 1).
JP 2002-265089 A

  A plurality of holding members are provided in the width direction of the recording paper, but if the urging force of the urging means varies among the plurality of holding members, the force that presses the recording paper in the paper width direction varies, thereby causing a skew. May occur. Therefore, it is preferable that the holding member is configured to have a smaller number of holding members with respect to the recording paper by forming the size in the paper width direction larger.

  On the other hand, when the holding member is formed large in the paper width direction, as described in Patent Document 1, one conveyance driven roller is provided for one holding member (holder) and both ends of the rotation shaft are urged. The transport driven roller also needs to be elongated in the paper width direction at the same time. However, if the transport driven roller is formed long in the paper width direction, the roller outer peripheral surface cannot be evenly contacted with the recording paper due to deformation during molding or aging, which may cause damage to the recording surface. In addition, the contact pressure of the roller outer peripheral surface with respect to the recording paper varies, which may cause a skew.

  On the other hand, when a plurality of transport driven rollers are provided on one holding member, the contact pressure of the transport driven roller with respect to the recording paper is likely to vary among the rollers, and the recording paper on the outer peripheral surface of the single transport driven roller is also provided. As a result, the recording surface may be damaged or cause skew as described above.

  Therefore, the present invention has been made in view of such a situation, and an object of the present invention is to provide a structure in which a plurality of conveyance driven rollers are provided on one holding member, and the contact pressure with respect to the recording paper is increased between the respective conveyance driven rollers. An object of the present invention is to provide a conveying device in which the contact pressure of the outer peripheral surface of the roller with respect to the recording paper is evenly uniform even with one conveying driven roller.

  In order to solve the above-described problem, a recording medium conveyance device according to a first aspect of the present invention includes a conveyance drive roller that is rotationally driven and a conveyance driven roller that is elastically contacted with the conveyance drive roller and is driven to rotate. A recording medium transport apparatus for transporting a recording medium, wherein a shaft body that extends in an axial direction of the transport driving roller and is held by a holding member passes through the plurality of transport driven rollers, and the shaft body is attached. The urging means is urged toward the transport driving roller, and the urging force of the urging means is configured to act on both sides of the plurality of transport driven rollers. .

  According to this aspect, the shaft body that passes through the plurality of conveyance driven rollers is urged toward the conveyance drive roller by the urging means, and the urging force of the urging means is the plurality of conveyance driven rollers. Therefore, an urging force always acts on both sides of each conveyance driven roller. Therefore, compared to a configuration in which only the both ends of the shaft body are urged, the urging force is less likely to vary among the plurality of conveying driven rollers, and the urging force always acts on both sides of the conveying driven roller. However, the contact pressure on the recording medium on the outer peripheral surface of the roller tends to be uniform in the roller axial direction. Accordingly, it is possible to prevent skew due to variation in the contact pressure with respect to the recording medium among the plurality of transport driven rollers, and also in one transport driven roller, the contact surface with respect to the recording medium on the outer peripheral surface of the roller varies. Can be prevented from being damaged.

The recording medium conveyance device according to a second aspect of the present invention is the recording medium conveyance device according to the first aspect, wherein the urging means includes the shaft body on each side of the plurality of conveyance driven rollers. It is characterized by being directly energized.
According to this aspect, since the urging means is configured to directly urge the shaft body on both sides of each of the plurality of transport driven rollers, between the positions where the urging forces are applied. The biasing force is unlikely to vary, and the effect of the first aspect can be obtained more reliably.

The recording medium transport apparatus according to a third aspect of the present invention is the recording medium transport apparatus according to the first aspect, wherein the biasing means biases the shaft body via the holding member. It is characterized by comprising an urging means and a second urging means for directly urging the shaft body.
According to this aspect, the urging means includes first urging means for urging the shaft body via the holding member, and second urging means for directly urging the shaft body. Since it is comprised, the attitude | position of the said holding member can be controlled, urging | biasing the said shaft body by the said 1st urging | biasing means.

A recording medium transport apparatus according to a fourth aspect of the present invention is the recording medium transport apparatus according to the third aspect, wherein the shaft body is held by the first biasing means at the shaft ends on both sides. And is urged directly between the shaft ends on both sides by the second urging means.
According to this aspect, since the portion where the holding member (first urging means) applies the urging force to the shaft body is the shaft end portions on both sides of the shaft body, the holding member (first urging force) The variation in the axial direction is less likely to occur when the means) applies a biasing force to the shaft body.

A recording medium transport apparatus according to a fifth aspect of the present invention is the recording medium transport apparatus according to any of the first to fourth aspects, wherein the holding member is seen from the side of the recording medium transport path. The holding member is supported so as to be swingable, and is attached to a main frame constituting a base of the recording medium transporting device via a subframe to which the urging means can be attached.
According to this aspect, an assembly is assembled in advance by these constituent members of the holding member, the urging means, the shaft body, the transport driven roller, and the subframe, and the assembly is attached to the main frame serving as the base of the recording medium transport device Since it can be attached, assembly workability is improved.

  The recording medium transport apparatus according to a sixth aspect of the present invention is the recording medium transport apparatus according to any one of the first to fifth aspects, wherein the holding member is disposed on the transport reference position side of the recording medium. Are set to be equal to or larger than the width-direction dimension of the recording medium of a specific size, and the plurality of transport driven rollers are arranged at substantially equal intervals in the width direction of the recording medium of the specific size. In addition, the urging force of the urging means is set so that the load when each of the conveyance driven rollers comes into contact with the recording medium is substantially equal.

  When the plurality of transport driven rollers press the recording medium with the transport driving roller, the contact position of the transport driven roller with respect to the transport driving roller (contact position in the transport direction of the recording medium) is between the transport driven rollers. If it varies, the feeding force of the recording medium varies in the width direction, which causes a skew. When a plurality of holding members are engaged with a recording medium of a specific size, the contact position between the plurality of transport driven rollers that press the recording medium of the specific size due to variations in the mounting position of the holding member. Variations are likely to occur.

  However, according to this aspect, since the width direction dimension of the holding member arranged on the conveyance reference position side of the recording medium is set to be equal to or larger than the width direction dimension of the recording medium having the specific size, A plurality of holding members do not relate to the medium, that is, the recording medium of a specific size is pressed only by the conveyance driven roller provided on one holding member, so that the above-described variation in the contact position is prevented and skew is prevented. Can be prevented.

  In addition, the plurality of transport driven rollers are arranged at substantially equal intervals in the width direction of the recording medium of a specific size, and the load when each transport driven roller comes into contact with the recording medium becomes substantially equal. Since the biasing force of the biasing means is set, it is possible to reliably prevent the occurrence of skew when the recording medium is transported.

  According to a seventh aspect of the present invention, in the recording medium conveyance device according to the fifth or sixth aspect, the contact position of the conveyance driven roller with respect to the conveyance driving roller can be adjusted. The attachment posture of the sub-frame with respect to the main frame is configured to be adjustable.

  According to this aspect, the mounting posture of the subframe with respect to the main frame is adjustable so that the contact position of the conveyance driven roller with respect to the conveyance driving roller can be adjusted. Even if the contact position variation as described above occurs between a plurality of transport driven rollers that are pivotally supported by one holding member due to a decrease in accuracy, this can be corrected and the occurrence of skew can be reliably prevented. Can do.

  A recording medium conveyance device according to an eighth aspect of the present invention is the recording medium conveyance device according to any of the fourth to seventh aspects, wherein the frictional force between the shaft body and the holding member is The total sum of friction forces between the shaft body and the second urging means is configured to be larger than the total friction forces between the shaft body and the plurality of transport driven rollers, so that the shaft body is In addition to being provided in a fixed state with respect to the holding member, the conveyance driven roller is configured to rotate relative to the shaft body.

  According to this aspect, the shaft body is provided in a fixed state with respect to the holding member, and the transport driven roller is configured to rotate relative to the shaft body. During rotation, abnormal noise due to sliding between the holding member and the shaft does not occur. Further, if the shaft body rotates with respect to the holding member, there is a possibility that the conveyance accuracy of the recording medium may be reduced due to bending or eccentricity of the shaft body. Therefore, such a problem does not occur.

  A recording apparatus according to a ninth aspect of the present invention is a recording apparatus comprising recording means for recording on a recording medium, wherein the recording medium conveying apparatus according to any one of the first to eighth aspects is provided. It is characterized by having. According to this aspect, in the recording apparatus, it is possible to obtain the same effect as any of the first to eighth aspects described above.

  A liquid ejecting apparatus according to a tenth aspect of the present invention includes a liquid ejecting unit that ejects liquid onto a medium to be ejected, a transport driving roller that is provided upstream of the liquid ejecting unit, and is driven to rotate, and the transport driving roller A liquid ejecting apparatus that includes a conveyance driven roller that is elastically contacted to rotate and is driven to rotate. The liquid ejecting apparatus includes a plurality of the conveyance shafts that extend in an axial direction of the conveyance driving roller and are held by a holding member. The driven roller is passed through, and the shaft body is urged by the urging means toward the conveyance drive roller, and the urging force of the urging means is applied to each side of the plurality of conveyance driven rollers. It is configured to act.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic side sectional view of an ink jet printer (hereinafter referred to as “printer”) 1 which is an embodiment of a “recording apparatus” or “liquid ejecting apparatus” according to the present invention, and FIG. 3, FIG. 3 and FIG. 4 are perspective views showing the mounting state of the paper guide upper unit 9 (FIG. 3 is a view from the front side of the apparatus, FIG. 4 is a view from the back side of the apparatus), and FIG. FIG. 6 is a sectional view taken along the line BB in FIG. 5, FIG. 7 is a sectional view taken along the line AA in FIG. 5, FIG. 8 is a sectional view taken along the line CC in FIG. FIG. 10 is a perspective view showing a mounting state after the paper guide 44, and FIGS. 11A to 11C are explanatory views showing a method for attaching the sheet material 38 (a perspective view of the paper guide top 43). It is.

  The overall configuration of the printer 1 will be outlined below with reference to FIG. The printer 1 is provided with a rear feeding device 2 at the rear of the device and a front feeding device 3 at the bottom of the device. From these two feeding devices to the conveying means 5, "recording medium" or "ejection medium" The recording paper is fed. The recording sheet is conveyed by the conveying means 5 to the recording means 4 (recording head 48). After recording is performed, the recording paper is discharged by a discharging means 6 to a stacker (not shown).

Hereinafter, the components on the paper transport path will be described in more detail.
The rear feeding device 2 includes a hopper 12, a feeding roller 11, a retard roller 13, a return lever 14, and other components not shown.
The hopper 12 is formed of a plate-like body, and is provided so as to be able to swing around an upper swing fulcrum 12a. By swinging, the paper P supported in an inclined posture on the hopper 12 is pressed against the feeding roller 11. The pressure contact posture to be switched and the separation posture to be separated from the feeding roller 11 are switched.

  The feeding roller 11 has a circular shape and rotates to feed the uppermost sheet P in pressure contact to the downstream side. The retard roller 13 has an outer periphery formed of an elastic material and is provided so as to be able to press contact with the feed roller 11 and is provided with a predetermined rotational resistance by a torque limiter mechanism. The paper P is clamped between the paper 11 and the paper 11 to prevent double feeding of the paper. The paper return lever 14 returns the front end of the paper staying between the feed roller 11 and the retard roller 13 (second and subsequent papers to be multi-fed) onto the hopper 12.

On the other hand, the front feeding device 3 provided at the bottom of the printer 1 and configured to set paper from the front of the device includes a paper feeding cassette 25, a pickup roller 26, a feeding roller 28, a separation roller 29, An assist roller 30.
The pick-up roller 26 that is rotationally driven by a motor (not shown) rotates in contact with the uppermost one of the paper P set in the paper feed cassette 25 that can be mounted and removed from the front side of the apparatus. P is fed out of the paper cassette 25. The feeding roller 28 is rotationally driven by a motor (not shown), reverses the uppermost sheet P fed out from the sheet feeding cassette 25, and feeds it to the conveyance driving roller 41 after the sheet guidance 44.

  A separation roller 29 is provided at a position facing the outer peripheral surface of the feeding roller 28 so as to be able to advance and retreat with respect to the feeding roller 28, and when the uppermost sheet P is fed out from the sheet feeding cassette 25. Is formed by pressing the feeding roller 28 to form a nip point so that the leading edge of the next and subsequent sheets P fed from the sheet feeding cassette 25 connected to the uppermost sheet P to be fed is moved to the nip. Stay near the point. The assist roller 30 is provided so as to be in contact with the outer peripheral surface of the feeding roller 28, and the paper P is fed with the rotation of the feeding roller 28 by nipping the paper P with the feeding roller 28. Assist.

  Next, on the downstream side of the rear feeding device 2 and the front feeding device 3, a paper guiding post 44 for guiding the fed paper P to the conveying means 5, the paper guiding upper unit 9, and the paper P And an optical sensor 37 (see FIG. 3 and the like) for detecting passage, and the paper P fed by the rear feeding device 2 and the front feeding device 3 is on a paper guide as a “holding member”. 43 and the conveyance path formed between the sheet guide 44 as the “second guide member” and reach the conveyance means 5. Reference numeral 40 denotes a guide roller that forms the feeding posture of the paper P fed from the rear feeding device 2. The guide roller 40 is pivotally supported on the paper guide 43 so as to be freely rotatable. However, the guide roller 40 is not shown in FIGS.

  The transport means 5 includes a transport drive roller 41 that is rotationally driven by a motor, and a transport driven roller 42 that is pivotally supported on the paper guide 43 so as to be driven and rotated by being pressed against the transport drive roller 41. Yes. The conveyance drive roller 41 is provided with an adhesion layer in which wear-resistant particles are dispersed almost uniformly on the outer peripheral surface of a metal shaft extending in the paper width direction, and the conveyance driven roller 42 has a low friction such as polyacetal resin. A plurality of materials are provided in the axial direction of the transport driving roller 41 (details will be described later).

The sheet P that has reached the conveying unit 5 rotates toward the recording unit 4 (recording head 48) on the downstream side when the conveying drive roller 41 rotates while being nipped by the conveyance driving roller 41 and the conveyance driven roller 42. It is conveyed.
The recording head 48 is provided at the bottom of the carriage 46, and the carriage 46 is reciprocated in the main scanning direction by a drive motor (not shown) while being guided by a carriage guide shaft 47 extending in the main scanning direction (the front and back direction in FIG. 1). It is driven like this. The carriage 46 is equipped with independent ink cartridges (not shown) for a plurality of colors, and ink is supplied from the ink cartridges to the recording head 48. The carriage guide shaft 47 is supported by the main frame 7 having a substantially U shape in plan view.

A paper guide front 45 that supports the paper P from below is provided at a position facing the recording head 48, and the paper guide front 45 defines an interval between the paper P and the recording head 48.
On the downstream side of the recording unit 4, an auxiliary roller 57 that prevents the sheet P from being lifted from the sheet guide front 45 and a discharge unit 6 that discharges the recorded sheet P are provided. The discharge means 6 includes a discharge drive roller 55 that is rotationally driven by a motor (not shown), and a discharge driven roller 56 that is driven to rotate in contact with the discharge drive roller 55, and is a sheet on which recording is performed by the recording means 4. P is discharged to a stacker (not shown) provided on the front side of the apparatus when the discharge drive roller 55 is rotationally driven while being nipped by the discharge drive roller 55 and the discharge driven roller 56.

The above is the outline of the printer 1, and the paper guidance upper unit 9 will be described in detail below with reference to FIGS.
In the present embodiment, two unit bodies that support the transport driven roller 42 are provided in the main scanning direction (paper width direction), and the paper guiding upper unit 9 according to the embodiment of the present invention is shown in FIG. In this way, it is provided on the paper conveyance reference position side (one digit side: right side in FIG. 3). Since the paper guiding upper unit 9 shown in FIGS. 2 to 11 is provided on the paper conveyance reference position side, all the sizes of paper that can be conveyed pass between the paper guiding upper unit 9 and the paper guiding post 44. It will be.

  In FIG. 2, the paper guide upper unit 9 includes a subframe 8, a paper guide 43, a shaft 31, two coil springs 32, two coil springs 33, a shaft body 34, and three transport followers. A roller 42 and a sheet material 38 are provided. By assembling these components, the paper guiding upper unit 9 as a unit body is configured.

  The subframe 8 is formed by bending a metal plate material, and is formed so as to form a substantially U-shape in plan view by the frame engaging pieces 8a and 8b, and a tongue piece portion 8c is formed. Yes. The frame engaging pieces 8a and 8b are formed with bearing portions 8f and 8g, and the shaft 31 is pivotally supported by the bearing portions 8f and 8g. The paper guide upper 43 is provided so as to be able to swing with respect to the subframe 8 so that the shaft 31 is set as the swing center, and the subframe 8 (paper guide upper unit 9) is attached to the main frame 7. As a result, the upper paper guide 43 is provided so as to be swingable when viewed from the side of the paper transport path.

  The paper guide top 43 is formed of a resin material so as to have a certain degree of flexibility. As described above, the paper guide top 43 is supported by the subframe 8 so as to be swingable. The shaft body 34 is pivotally supported. The shaft 31 passes through the coil portions of the two coil springs 32 and the coil portions of the two coil springs 33, and the two coil springs 32 are biased between the subframe 8 and the paper guide top 43. The two coil springs 33 exert a biasing force between the subframe 8 and the shaft body 34.

  More specifically, one end 32 a of the coil spring 32 as “first urging means” extends from the coil portion toward the transport driven roller 42, and the other end 32 b is hooked on a hook portion 8 h formed on the subframe 8. By doing so (see also FIG. 4), the one end 32a urges the paper guide upper 43 from above. Further, one end 33 a of the coil spring 33 as “second urging means” extends from the coil portion toward the shaft body 34, and the other end 33 b is hooked on the hook portion 8 h formed in the subframe 8. One end 33a directly biases the shaft body 34.

  As shown in FIGS. 6 and 8, the shaft body 34 is restricted from moving upward by the bearing portion 43 b of the paper guide upper 43 at the shaft ends on both sides, and shown in FIGS. 7 and 8 at the intermediate portion. In this way, the downward movement is restricted by the bearing portion 43c of the paper guide upper 43, but the slight movement in the vertical direction is allowed while the movement in the vertical direction is restricted in this way. ing. The shaft body 34 receives the urging force of the coil spring 32 via the bearing portions 43b at the shaft end portions on both sides, and directly receives the urging force of the coil spring 33 at the intermediate portion.

  The shaft body 34 is a member that constitutes the rotation shaft of the transport driven roller 42. However, after the shaft body 34 is incorporated into the paper guide upper unit 9, it does not rotate with respect to the paper guide upper 43, but becomes a fixed shaft. The transport driven roller 42 rotates relative to the shaft body 34. Specifically, one end 33a of the coil spring 33 directly urges the shaft body 34, and the inner peripheral surface of the transport driven roller 42 is formed of a low friction material or a lubricant is interposed, whereby the shaft body 34 and the paper The total frictional force between the shaft 43 and the one end 33a of the coil spring 33 is the frictional force between the shaft 34 and the plurality of conveying driven rollers 42. It is configured to be larger than the sum of.

  Thereby, when the conveyance driven roller 42 rotates, no abnormal noise is generated due to the sliding between the paper guide top 43 and the shaft body 34. Further, if the shaft body 34 rotates with respect to the paper guide top 43, there is a risk that the paper conveyance accuracy may be lowered due to the deflection or eccentricity of the shaft body 34. Since it is provided in a fixed state, such a problem does not occur.

  6 is a straight line connecting the axis position of the conveyance drive roller 41 and the axis position of the conveyance driven roller 42 as viewed from the side of the sheet conveyance path, and a vertical line (gravity direction). When the angle α varies between the plurality of transport driven rollers 42, that is, when the contact position of the transport driven roller 42 with respect to the transport drive roller 41 varies. The feed force applied to the sheet by the transport drive roller 41 and the transport driven roller 42 may vary among the transport driven rollers 42, resulting in a skew.

  In order to solve such a problem, the following configuration is adopted in the present embodiment. First, the width direction dimension of the paper guide upper 43 is set to be equal to or larger than the paper width dimension of a specific size, and in this embodiment, is set to a dimension capable of covering a 4-inch width sheet. Accordingly, a plurality of paper guides 43 are not involved with a paper having a width dimension of 4 inches or less, that is, the paper is pressed only by the transport driven roller 42 supported by one paper guide 43, so Variations in the contact position with respect to the conveyance drive roller 41 among a plurality (three in this embodiment) of the conveyance driven rollers 42 supported by the paper guide 43 can be suppressed.

  Further, as shown in FIGS. 5 and 8, the three driven rollers 42 are arranged at substantially equal intervals in the paper width direction. And it is comprised so that urging | biasing force may act on both sides of each conveyance driven roller 42 especially so that urging | biasing force may act on not only the both-ends shaft end part of the shaft body 34 but a center site | part, The urging forces of the coil springs 32 and 33 are set so that the load when the conveyance driven roller 42 comes into contact with the paper is substantially equal. Accordingly, the force with which each conveyance driven roller 42 presses the sheet is equalized, and the occurrence of skew due to variations in pressing load can be prevented. Further, since the load when the transport driven roller 42 contacts the paper does not concentrate on one place, the paper is not damaged.

This will be described in more detail with reference to FIG. FIG. 12 is a diagram schematically showing the positional relationship between the urging force applied to the shaft body 34 and the transport driven roller 42 and the contact pressure of the transport driven roller 42 with respect to the paper P. Reference numeral F ₁ denotes the coil spring 32. the one end 32a (via upper paper guide 43) biasing force applied to the shaft body 34, reference numeral F ₂ is (directly) by one end 33a of the coil spring 33 shows the biasing force applied to the shaft 34 ing. The one end 32 a of the coil spring 32 is indicated by a broken line because the coil spring 32 applies a biasing force to the shaft body 34 via the paper guide top 34. Reference numeral f ₃ indicates the contact pressure of the transport driven roller 42 with respect to the paper P.

As shown in the figure, the coil spring 32 is configured such that an urging force always acts on both sides of each of the transport driven rollers 42A, 42B, and 42C, and the contact pressure (f ₃ ) of each roller becomes equal. 33 is set, it is possible to prevent the occurrence of skew due to variation in the urging force between the transport driven rollers 42A, 42B, and 42C. In each of the rollers, the contact pressure on the sheet P of the roller outer peripheral surface is not fluctuated at the roller axis direction and uniformly distributed load f _3. Therefore, it is possible to prevent the recording surface from being damaged when the roller hits the sheet P.

In this embodiment, the force F _1, but through the upper paper guide 43 is imparted to the shaft 34, similarly to the force F _2, configured so as to impart a direct biasing force to the shaft 34 May be. By configuring in this way, the urging force is unlikely to vary between positions to which each urging force is applied, and the above-described effects can be obtained more reliably.

  Next, the paper guide upper unit 9 (sub-frame 8) is attached to the main frame 7 in an adjustable manner so that the contact position of the transport driven roller 42 with respect to the transport drive roller 41 can be adjusted. (In other words, even if the angle α in FIG. 6) varies between the three transport driven rollers 42, this can be corrected. Hereinafter, a detailed description will be given of a structure that enables adjustment of the mounting posture of the paper guiding upper unit 9 (subframe 8).

  As shown in FIG. 2, an elongated hole 8e and a boss 8d are formed in the tongue 8c of the sub-frame 8, and the sub-frame 8 is connected to the main frame 7 as shown in FIG. A hole 7c through which the fixing screw 35 is fixed and a boss 8d formed on the tongue piece 8c of the subframe 8 are loosely formed. When the subframe 8 is attached to the main frame 7 and the fixing screw 35 is loosened, the subframe 8 can swing around the boss 8d (in the direction indicated by the arrow A in FIG. 8). As a result, the mounting posture of the unit 9 on the paper guide changes. That is, with reference to the central transport driven roller 42 among the three transport driven rollers 42, the contact positions of the transport driven rollers 42 on both sides with respect to the transport drive roller 41 (in other words, in FIG. The angle α) can be adjusted.

  On the other hand, the frame engaging pieces 8a and 8b of the subframe 8 have a hook shape, and the frame engaging pieces 8a and 8b are connected to the hooked portions 7b and 7b formed on the main frame 7. Each is configured to be hooked. Here, when the paper guiding upper unit 9 is attached to the main frame 7, the frame engaging pieces 8a and 8b are pressed against the upper edges of the locked portions 7b and 7b by the urging force of the coil springs 32 and 33 ( Direction indicated by arrow B in FIG. 7). Therefore, by utilizing this property, the mounting posture of the paper guide unit 9 is adjusted by interposing the spacer 36 between the frame engaging pieces 8a, 8b and the upper edges of the locked portions 7b, 7b.

  For example, when the mounting orientation of the paper guide unit 9 is tilted clockwise in FIG. 8, the spacer 36 is interposed between the right frame engaging piece 8a and the upper edge of the locked portion 7b. As a result, the rocking fulcrum of the paper guide upper 43 moves downward on the right side (the frame engagement piece 8a side), so that the right conveyance driven roller 42 (indicated by reference numeral 42A in FIG. 8) and the conveyance are supported. The point of contact with the driving roller 41 is shifted downstream in the sheet conveyance direction (right side in FIG. 6) (that is, the angle α in FIG. 6 is increased).

  When the mounting orientation of the paper guide unit 9 is tilted in the counterclockwise direction of FIG. 8, the description is omitted because it may be reversed. Since the spacer 36 is interposed between the frame engaging pieces 8a and 8b and the upper edges of the locked portions 7b and 7b as described above, the frame engaging pieces 8a and 8b are attached to the hooked portions 7b and 7b. It is desirable that the frame engaging pieces 8a and 8b have a sufficient allowance so that the frame engaging pieces 8a and 8b can be moved up and down in the state of being hooked to each other. Further, when the mounting posture of the paper guide unit 9 is adjusted, one of the bearing portions 43b and 43b that urge both end portions of the shaft body 34 of the transport driven roller 42 is displaced upward. The front 43 is preferably formed of a flexible material. Thereby, even if the attachment attitude | position of the paper guide unit 9 is adjusted, the both ends of the shaft 34 can be reliably urged | biased by the bearing parts 43b and 43b.

  As described above, since the mounting posture of the paper guide unit 9 (subframe 8) with respect to the main frame 7 is configured to be adjustable, the conveyance of the conveyance driven roller 42 is caused by a decrease in the manufacturing accuracy of parts and the assembly accuracy of the apparatus. Even when the contact position with respect to the drive roller 41 varies between the three transport driven rollers (the transport driven rollers indicated by reference numerals 42A, 42B, and 42C in FIG. 8), this can be corrected, and the sheet It is possible to reliably prevent the occurrence of skew during conveyance.

  Subsequently, the mounting structure of the optical sensor 37 will be described with reference to FIGS. 9 to 11. The optical sensor 37 is configured such that the light emitting portion 37 a and the light receiving portion 37 b are integrated to form a substantially U-shape, and its optical axis is between the paper guide upper 43 and the paper guide lower 44. In this way, the passage of the leading or trailing edge of the sheet can be detected.

  FIG. 10 shows the printer substrate in a state before the paper guide upper unit 9 is attached to the main frame 7. As shown in the figure, the optical sensor 37 is on the paper transport reference position side (one digit side: right side in FIG. 10). ) Is provided so as to protrude from the outside to the inside of the sheet conveyance path. The optical sensor 37 is fixed to the post-paper guide 44 as shown in FIG. 9. After the paper guide 44 is attached in advance to the main frame 7 as shown in FIG. Installed state. In addition, after the paper guidance 44, a window hole for exposing the light receiving portion 37b is formed in advance.

  In the mounted state shown in FIG. 10, the light emitting portion 37a is located at a position where it interferes with the paper guide top 43. Accordingly, the paper guide top 43 is formed with a cutout portion 43a for receiving the light emitting portion 37a as shown in FIG. Has been. The notch 43a is formed so as to have an opening on the paper conveyance reference position side and on the side facing the paper guide 44, and the opening on the side facing the paper guide 44 in the notch 43a. However, as shown in FIG. 5, it is covered with the sheet material 38 except for the region through which the optical axis of the optical sensor 37 passes (reference numeral 37c in FIG. 5 indicates the optical axis of the optical sensor 37).

  The sheet material 38 has a strip shape, and has window holes 38a and 38a formed at both ends, and is formed of a flexible material. On the other hand, a hook 43d is formed on the paper guide 43, and one side of the window hole 38a is hooked on the hook 43d (FIG. 11B) and wound through the through hole 43f, and the other side of the window hole 38a. The sheet material 38 is attached by hooking the hole 38a to the hook 43d (FIG. 11C). Reference numeral 43e denotes a tension applying portion that prevents the sheet material 38 from being extremely slackened by urging the sheet material 38 wound around the paper guide 43 from the inside to the outside. To do.

  As described above, the light emitting portion 37a of the optical sensor 37 protrudes from the outside of the paper transport path to the inside, that is, toward the paper guide top 43, at a position facing the side surface of the paper guide top 43 on the paper transport reference position side. A notch 43a for receiving the light emitting part 37a is formed on the paper guide 43. Accordingly, when the paper guide upper unit 9 is attached to the base of the printer 1 configured as shown in FIG. 10, the paper guide upper unit 9 is moved so as to slide from the left to the right in FIG. The paper guide upper unit 9 is attached so that the light emitting portion 37a is accommodated inside 43a.

  As described above, the optical sensor 37 is not directly attached to the base of the printer 1, but is attached to the main frame 7 after the paper guide 44 is attached in advance and the optical sensor 37 is attached to the main body of the printer 1. Since it is attached, workability at the time of attaching the optical sensor 37 is improved, and attachment position adjustment can be easily performed.

  Further, in the case where a simple window hole for exposing the light emitting portion 37a is formed in the paper guide 43 instead of the notch 43a as in the present embodiment, the paper guide upper unit 9 is connected to the main frame. Since it is necessary to attach the optical sensor 37 after being attached to 7, the workability of attaching the optical sensor 37 and the workability during position adjustment may be reduced. At the same time, it may be necessary to configure the light emitting portion 37a and the light receiving portion 37b of the optical sensor 37 separately, and for example, the position where the light emitting portion 37a is fixed is separated in a direction perpendicular to the paper transport path. Therefore (upward direction: for example, any place on the main frame 7), the mounting position accuracy of the optical sensor 37 may be reduced. However, since the notch 43a as described above is formed, such a problem does not occur.

  Further, since the opening on the side facing the post-paper guide 44 in the notch 43a is covered with the sheet material 38, when the paper passes between the upper paper guide 43 and the post-paper guide 44, the front end of the paper Can be prevented from being caught in the opening of the notch 43a, and the occurrence of skew due to the folding of the leading edge of the paper and the leading edge of the paper being caught in the opening can be prevented. In addition, since the sheet | seat material 38 has such a function, it is preferable that the surface has a low coefficient of friction between the sheets.

1 is a schematic side sectional view of a printer according to the present invention. The perspective view of a paper guidance upper unit. The perspective view which shows the attachment state of the unit on paper guidance. The perspective view which shows the attachment state of the unit on paper guidance. The top view which looked at the paper guidance upper unit from the downward direction. BB sectional drawing of FIG. AA sectional drawing of FIG. CC sectional drawing of FIG. The perspective view after paper guidance. The perspective view which shows the attachment state after paper guidance. (A)-(C) is explanatory drawing which shows the attachment method of a sheet | seat material. The figure which shows typically the positional relationship of the urging | biasing force provided to a shaft body, and a conveyance driven roller, and the contact pressure with respect to the paper of a conveyance driven roller.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer, 2 Rear feeding device, 3 Front feeding device, 4 Recording means, 5 Conveying means, 6 Ejecting means, 7 Main frame, 7a Hole, 7b Covered part, 7c
Hole, 8 Subframe, 8a, 8b Frame engaging piece, 8c Tongue piece, 8d Boss, 8e Long hole, 9 Paper guide upper unit, 11 Feeding roller, 12 Hopper, 13 Retard roller, 14 Return lever, 25 Paper feeding cassette, 26 pickup roller, 28 feeding roller, 30 assist roller, 31 shaft, 32, 33 coil spring, 34 shaft body, 35
Fixing screw, 36 spacer, 37 optical sensor, 37a light emitting section, 37b light receiving section, 38 sheet material, 40 guide roller, 41 transport driving roller, 42 transport driven roller, 43 on paper guide, 44 after paper guide , 45 Before paper guidance, 46 Carriage, 47 Carriage guide shaft, 48 Recording head, 55 Ejection drive roller, 56 Ejection driven roller, 57 Auxiliary roller, P Recording paper

Claims (10)

A recording medium conveying apparatus for conveying a recording medium, comprising a conveyance driving roller that is rotationally driven and a conveyance driven roller that is elastically contacted with the conveyance driving roller to rotate.
A shaft body extending in the axial direction of the transport driving roller and held by a holding member passes through the plurality of transport driven rollers,
The shaft body is urged toward the conveyance drive roller by the urging means, and the urging force of the urging means is configured to act on both sides of the plurality of conveyance driven rollers. Yes,
A recording medium conveying apparatus characterized by the above. The recording medium conveyance device according to claim 1, wherein the urging unit is configured to directly urge the shaft body on both sides of each of the plurality of conveyance driven rollers.
A recording medium conveying apparatus characterized by the above. 2. The recording medium conveying apparatus according to claim 1, wherein the urging unit includes a first urging unit that urges the shaft body via the holding member, and a second urging unit that directly urges the shaft body. And a force means,
A recording medium conveying apparatus characterized by the above. The recording medium conveyance device according to claim 3, wherein the shaft body is urged by the first urging unit toward the conveyance driving roller via the holding members at both axial ends.
Directly biased between the shaft ends on both sides by the second biasing means,
A recording medium conveying apparatus characterized by the above. 5. The recording medium conveyance device according to claim 1, wherein the holding member supports the holding member and swings the recording medium conveyance path so as to be swingable when viewed from a side. It is attached to a main frame that constitutes a base of the recording medium transporting device via a subframe to which the means can be attached.
A recording medium conveying apparatus characterized by the above. In the recording medium conveyance device according to any one of claims 1 to 5, a plurality of the holding members are arranged in parallel in the width direction of the recording medium,
The width direction dimension of the holding member arranged on the conveyance reference position side of the recording medium is set to be equal to or larger than the width direction dimension of the recording medium of a specific size, A plurality of the transport driven rollers are arranged at substantially equal intervals, and the biasing force of the biasing means is set so that the load when each of the transport driven rollers comes into contact with the recording medium is approximately equal. A recording medium conveying apparatus characterized by the above.   The recording medium conveyance device according to claim 5 or 6, wherein a mounting posture of the sub frame with respect to the main frame is adjustable so that a contact position of the conveyance driven roller with respect to the conveyance driving roller can be adjusted. A recording medium transporting device, characterized in that:   8. The recording apparatus according to claim 4, wherein a total sum of a friction force between the shaft body and the holding member and a friction force between the shaft body and the second urging means is By being configured to be larger than the sum of the frictional forces between the shaft body and the plurality of transport driven rollers, the shaft body is provided in a fixed state with respect to the holding member, and the transport driven roller is configured to be the shaft body. A recording medium transporting apparatus, wherein the recording medium transporting apparatus is configured to rotate relative to the recording medium.   9. A recording apparatus comprising recording means for recording on a recording medium, comprising the recording medium conveying apparatus according to claim 1. Liquid ejecting means for ejecting liquid onto the ejected medium;
A liquid ejecting apparatus comprising: a transport driving roller that is provided upstream of the liquid ejecting means; and a transport driving roller that is rotationally driven and a transport driven roller that elastically contacts the transport driving roller and is driven to rotate.
A shaft body extending in the axial direction of the transport driving roller and held by a holding member passes through the plurality of transport driven rollers,
The shaft body is urged toward the conveyance drive roller by the urging means, and the urging force of the urging means is configured to act on both sides of the plurality of conveyance driven rollers. Yes,
A liquid ejecting apparatus.

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