Sheet conveyance device and image forming device

Abstract

This sheet conveyance device is provided with: a movement guide (300) capable of moving between a first position for guiding a sheet to a first conveyance path by means of first and second ribs (303, 700) and a second position for guiding the sheet to a second conveyance path by means of the first and second ribs; and an elastic member (600) against which the first rib (303) abuts and elastically deforms when the movement guide moves from the first position to the second position. In the second rib (700), at least a part of a sheet guide surface for guiding the sheet is constituted by a sliding member (500) having higher slidability with respect to the sheet than the first rib. When the movement guide moves from the first position to the second position, the first rib abuts the elastic member before the second rib abuts the first guide.

Description

Sheet transport device and image forming apparatus

[0001] This disclosure relates to a sheet transport device for transporting sheets, and an image forming apparatus.

[0002] For example, some image forming machines such as photocopiers and printers are equipped with a switching guide (a so-called flapper) for switching the destination to which a sheet is transported (see Patent Document 1). This switching guide requires lightweight design to achieve high-speed switching. For this reason, the switching guide is configured to have multiple guide ribs supported by a support portion extending in the sheet width direction, and to guide the sheet with the outer edges of the multiple guide ribs. However, when guiding a sheet with multiple guide ribs, there is a risk of defects or streaks being formed on the sheet. Therefore, it is conceivable to attach highly sliding guide members to the multiple guide ribs, but attaching guide members to all guide ribs would hinder weight reduction. For this reason, Patent Document 1 proposes attaching guide members only to selected guide ribs among the multiple guide ribs.

[0003] Japanese Patent Publication No. 2023-64556

[0004] Incidentally, when the switching guide described above is switched, for example by a solenoid, it may collide with fixed components such as transport guides, potentially generating noise.

[0005] Therefore, this disclosure provides a sheet transport device and an image forming apparatus that can reduce noise when switching the moving guide.

[0006] One aspect of the present disclosure is a sheet conveying device comprising: a conveying unit for conveying a sheet; a first conveying path through which the sheet passes, having a first guide for guiding the sheet conveyed by the conveying unit; a second conveying path branching off from the first conveying path, through which the sheet conveyed by the conveying unit passes; a movable guide having first and second ribs spaced apart in a width direction perpendicular to the sheet conveying direction, and movable to a first position where the sheet is guided to the first conveying path by the first and second ribs, and a second position where the sheet is guided to the second conveying path by the first and second ribs; and an elastic member disposed on the first guide, which the first rib contacts and elastically deforms when the movable guide moves from the first position to the second position, wherein at least a portion of the sheet guide surface of the second rib is made of a sliding member that has higher sliding properties with respect to the sheet than the first rib, and the first rib contacts the elastic member before the second rib contacts the first guide when the movable guide moves from the first position to the second position.

[0007] One aspect of the present disclosure includes a conveying unit for conveying a sheet, a first conveying path through which the sheet passes, having a first guide for guiding the sheet conveyed by the conveying unit, a branching path branching from the first conveying path, a second conveying path through which the sheet conveyed by the conveying unit passes, and a plurality of ribs arranged at intervals in a width direction perpendicular to the sheet conveying direction, having a first position for guiding the sheet to the first conveying path or the second conveying path, a second position for guiding the sheet to the second conveying path, A sheet conveying device comprising: a movable guide that can be switched between two positions; an elastic member that elastically deforms when the first rib of the plurality of ribs comes into contact with the movable guide as it moves from the first position to the second position; and a sliding member that is attached to a rib different from the first rib among the plurality of ribs, guides the sheet, and has higher sliding properties with respect to the sheet than the first rib, wherein when the movable guide moves from the first position to the second position, the first rib comes into contact with the elastic member before the sliding member comes into contact with the first guide.

[0008] According to this disclosure, noise can be reduced when switching between mobile guides.

[0009] Other features and advantages of this disclosure will become apparent from the following description with reference to the accompanying drawings. In the accompanying drawings, the same or similar components are given the same reference numeral.

[0010] This is a schematic diagram showing a printer according to the first embodiment. This is a cross-sectional view showing the flapper and its vicinity in the first position. This is a cross-sectional view showing the flapper and its vicinity in the second position. This is a perspective view showing the first guide and the second guide with the flapper removed. This is a side view showing the branch section with the flapper and its vicinity. This is a side view showing the branch section and its vicinity with the flapper removed. This is a perspective view showing the side of the first guide section of the flapper with the add-on guide rib attached. This is a perspective view showing the side of the second guide section of the flapper with the add-on guide rib attached. This is a cross-sectional view showing the positional relationship between the add-on guide rib according to the first embodiment, the target rib to which it is attached, and the roller. This is a cross-sectional view showing the drive mechanism of the flapper. This is a cross-sectional view showing the positional relationship between the add-on guide rib according to the second embodiment, the target rib to which it is attached, and the roller. This is a cross-sectional view showing the positional relationship between the add-on guide rib according to the third embodiment, the target rib to which it is attached, and the roller. This is a cross-sectional view showing the positional relationship between the add-on guide rib according to the fourth embodiment, the target rib to which it is attached, and the roller. This is a cross-sectional view showing the positional relationship between the add-on guide rib according to the fifth embodiment, the target rib to which it is attached, and the roller.

[0011] <First Embodiment> The first embodiment will be described in detail below with reference to the drawings. In this specification, the subscripts used in the reference numerals are used to distinguish different types of similar components (parts). When there is no particular need to distinguish them, the reference numerals without subscripts will be used in the description.

[0012] [Printer Configuration] First, a printer 100, which is an example of an image forming apparatus according to the first embodiment, will be described using Figure 1. Figure 1 is a schematic diagram showing the printer according to the first embodiment. In Figure 1, the X direction is the horizontal direction and is the left-right direction of the printer 100. The Y direction is also the horizontal direction and is the front-to-back direction of the printer 100, and is also the width direction perpendicular to the sheet transport direction. The Z direction is the up-and-down direction.

[0013] As shown in Figure 1, the printer 100 is a so-called laser beam printer and has a printer body 101, which is the main body of the device. Inside the printer body 1, there is an image forming unit 102 for forming an image on a sheet and a sheet transport unit 104 for transporting the sheet. The printer 100 also has an image reading device 103 installed above the printer body 101. A discharge space P for sheet ejection is formed between the image reading device 103 and the printer body 101. The printer body 101 also includes a sheet feeding unit 110 for feeding sheets S from a paper feed cassette 111 to the image forming unit 102, and a sheet transport unit 104 as a sheet transport device for transporting sheets from the image forming unit 102 to the outside of the printer 100. The printer body 101 also includes a reversal transport unit 20 for transporting the sheet with the image formed on the first surface back to the image forming unit 102. The sheet transport section 104 includes, in more detail later, a fuser 150, a pair of post-fusing rollers 160, a first discharge roller pair 210, an upstream transport roller pair 180, a downstream transport roller pair 190, a second discharge roller pair 220, etc.

[0014] The image forming unit 102 includes a scanner unit 142, four process cartridges 140 for forming toner images of four colors: yellow (Y), magenta (M), cyan (C), and black (Bk), four photoreceptor drums 141, four developer units 143, and the like. The image forming unit 102 also includes an intermediate transfer unit 145 positioned above the process cartridges 140. The operation of these components will be described in detail in the image forming operation section below.

[0015] The intermediate transfer unit 145 includes an intermediate transfer belt 146 wrapped around the secondary transfer roller 131, etc. The intermediate transfer unit 145 also includes a primary transfer roller 144 located inside the intermediate transfer belt 146 and in contact with the intermediate transfer belt 146 at a position opposite the photoreceptor drum 141. The intermediate transfer belt 146 is positioned to contact each photoreceptor drum 141 and is driven by a drive unit (not shown) to rotate in the direction of arrow A. By applying a positive transfer bias to the intermediate transfer belt 146 using the primary transfer roller 144, the negative polarity toner images of each color on the photoreceptor drum 141 are sequentially transferred onto the intermediate transfer belt 146. As a result, a full-color image is formed on the intermediate transfer belt.

[0016] Furthermore, a secondary transfer roller 132 is provided in the intermediate transfer unit 145 at a position opposite the secondary transfer roller 131, which constitutes the secondary transfer section 130 that transfers the full-color image formed on the intermediate transfer belt to the sheet S. In addition, a fuser 150 is positioned above the secondary transfer roller 132, and a discharge section 200, which serves as a sheet discharge device, is positioned downstream of the fuser 150 in the sheet transport direction. The discharge section 200 is equipped with a first discharge roller pair 210 and a second discharge roller pair 220.

[0017] The printer 100 includes a feeding passage R for transporting sheets fed from the sheet feeding unit 110 to the image forming unit 102, and a first transport path R1 through which sheets with images formed by the image forming unit 102 pass to be transported to the first discharge roller pair 210. The printer 100 also includes a second transport path R2, which is a branch path branching off from the first transport path R1 at the branching section JN, and transports sheets to the second discharge roller pair 220. Furthermore, the printer 100 includes a re-transport passage R3 provided in the reversing transport unit 20, which re-transports sheets by connecting the second transport path R2 back to the first transport path R1. In the following description, the section from the image forming unit 102 to the branching section JN in the first transport path R1 is also referred to as the first upstream transport path R1a, and the section from the branching section JN to the first discharge roller pair 210 in the first transport path R1 is also referred to as the first downstream transport path R1b.

[0018] Furthermore, a pair of post-fixing rollers 160 is arranged in the first upstream transport path R1a to pull out and transport the sheet discharged from the fixer 150. This pair of post-fixing rollers 160 has a post-fixing inner roller 161 and a post-fixing outer roller 162 which acts as an upstream roller that contacts it to form a nip.

[0019] Furthermore, the second transport path R2 is equipped with an upstream transport roller pair 180 and a downstream transport roller pair 190 for transporting sheets that branch off from the first transport path R1 at the branching section JN. The upstream transport roller pair 180 has an upstream transport inner roller 181 and an upstream transport outer roller 182 that contacts it to form a nip. Similarly, the downstream transport roller pair 190 has a downstream transport inner roller 191 and a downstream transport outer roller 192 that contacts it to form a nip.

[0020] Furthermore, at the branching section JN that separates the first transport path R1 and the second transport path R2, there is a flapper 300 which will be described in more detail later as a moving guide or switching member. １ This is located. This Flapper 300 １ It can be switched between a first position P1 (see Figure 2A) and a second position P2 (see Figure 2B). Flapper 300 １ If the first position P1 is reached, the conveyed sheet is guided from the first upstream conveying path R1a to the first downstream conveying path R1b (i.e., to the first conveying path R1). Also, the flapper 300 １ If the position is the second position P2, the conveyed sheet is guided from the first upstream conveying path R1a to the second conveying path R2. Also, the first conveying path R1 has a flapper 300. １ A roller 230, acting as a rotating body, is positioned opposite to the conveyed sheet. The roller 230 is configured to rotate in accordance with the sheet being conveyed.

[0021] Furthermore, the second transport path R2 is equipped with a flapper 400 that can be switched between a position that guides the transported sheet to the second discharge roller pair 220 and a position that guides the sheet, which has been inverted by the second discharge roller pair 220 as described later, to the re-transport passage R3.

[0022] [Image Forming Operation] Next, the image forming operation of the printer 100 configured as described above will be explained. When the image forming operation is started, first, a laser beam is emitted from the scanner unit 142 based on image information from a personal computer or the like (not shown). This laser beam sequentially exposes the surface of the photoreceptor drum 141, whose surface is uniformly charged to a predetermined polarity and potential, to form an electrostatic latent image on the photoreceptor drum. After this, this electrostatic latent image is developed and made visible using toner. Then, the toner images of the four colors, yellow (Y), magenta (M), cyan (C), and black (Bk), on the photoreceptor drum are transferred to the intermediate transfer belt 146 by a transfer bias applied to the primary transfer roller 144, forming a full-color toner image on the intermediate transfer belt. The toner remaining on the photoreceptor drum is collected in an unshown toner discharge container by a cleaning unit (not shown) provided in the process cartridge 140.

[0023] In parallel with this toner image formation operation, the sheet S contained in the paper feed cassette 111 is fed out by the sheet feeding unit 110. After this, the sheet S is transported by the transport roller pair 121 to the registration roller pair 120, which acts as a skew correction unit, and the skew is corrected by the registration roller pair 120. Next, the transport roller pair 122 provided on the registration roller pair 120 rotates to align the leading edge of the skew-corrected sheet S with the full-color toner image on the intermediate transfer belt, and the sheet S is transported to the secondary transfer unit 130. Then, in the secondary transfer unit 130, the full-color toner image is transferred onto the sheet S all at once by the secondary transfer bias applied to the secondary transfer roller 132.

[0024] Next, the sheet S onto which the full-color toner image has been transferred is transported to the fuser 150, where heat and pressure are applied to melt and mix the toners of each color, fixing the toner image on the sheet S as a full-color image. After this, the sheet S with the fixed toner image is discharged, for example, by the first discharge roller pair 210 provided on the first transport path R1 to the discharge tray 170, which serves as a loading section at the bottom of the discharge space P. Alternatively, if, for example, the discharge tray 171 serving as a loading section is selected as the discharge destination, the flapper 300１ The sheet is moved from a first position P1, indicated by a solid line, which directs the sheet toward the first discharge roller pair 210, to a second position P2, indicated by a dashed line, which guides the sheet toward the reversing conveying section 20. As a result, the sheet is guided toward the second conveying path R2 and discharged by the second discharge roller pair 220 into the discharge tray 171 provided in the discharge space P.

[0025] Furthermore, when forming images on both sides of the sheet, the flapper 300 １ The sheet is moved from the first position P1 to the second position P2. As a result, the sheet with the image formed on the first surface reaches the second discharge roller pair 220, which is also a reversible inversion conveying section 20 provided in the second conveying path R2. After this, the flapper 400 is moved from the position indicated by the solid line, which directs the sheet toward the second discharge roller pair 220, to the position indicated by the dashed line, which directs the sheet toward the re-conveying passage R3 of the inversion conveying section 20. Then, due to the reversal of the second discharge roller pair 220, the sheet is conveyed to the re-conveying passage R3 in an inverted state. After this, the sheet is conveyed again to the secondary transfer section 130 via the re-conveying passage R3, and an image is formed on the second surface opposite to the first surface.

[0026] Then, after the toner image is fixed again by the fuser 150, the sheet S with images formed on both sides is discharged onto the discharge tray 170 by the first discharge roller pair 210. Alternatively, the sheet S with images formed on both sides is discharged onto the flapper 300. １ By moving it to the second position P2, it is discharged onto the discharge tray 171 provided in the discharge space P by the second discharge roller pair 220.

[0027] [Configuration of the branch section and its vicinity] Next, the configuration of the branch section JN and its vicinity described above will be explained using Figures 2A to 4. Figure 2A is a cross-sectional view showing the flapper in the first position and its vicinity. Figure 2B is a cross-sectional view showing the flapper in the second position and its vicinity. Figure 3 is a perspective view showing the first guide and the second guide with the flapper removed. Figure 4A is a side view showing the branch section with the flapper and its vicinity. Figure 4B is a side view showing the branch section and its vicinity with the flapper removed.

[0028] As described above, downstream of the fixing device 150 in the conveyance direction, a first conveyance path R1 and a second conveyance path R2 that branches from the first conveyance path R1 at a branch portion JN are arranged. As shown in FIGS. 2A and 2B, a flapper 300 that can switch between a first position P1 for guiding the sheet to the first conveyance path R1 and a second position P2 for guiding the sheet to the second conveyance path R2 is arranged at this branch portion JN. １ is arranged. The first upstream conveyance path R1a of the first conveyance path R1 is formed between a first guide G1 and a third guide G3 as guide members, and the first downstream conveyance path R1b is formed between the first guide G1 and a second guide G2. Further, the second conveyance path R2 is formed between the second guide G2 and the third guide G3.

[0029] Upstream of the branch portion JN in the conveyance direction, a post-fixing roller pair 160 is arranged at a position adjacent to the flapper 300 in the first upstream conveyance path R1a. １ The post-fixing inner roller 161 of this post-fixing roller pair 160 is arranged in a manner embedded in the guide surface of the first guide G1 (see FIG. 3), and the post-fixing outer roller 162 is arranged in a manner embedded in the guide surface of the third guide G3. The post-fixing inner roller 161 is a so-called single roller in which a roller portion that is in contact with the sheet and is composed of silicon, rubber, etc. supported by a support shaft is formed as a single piece in the width direction, and is a drive roller driven by a motor not shown. On the other hand, as shown by the dotted line in FIG. 4A, the post-fixing outer roller 162 has a support shaft 162b and a plurality of roller portions 162a as contact rotating portions that are in contact with the sheet. The plurality of roller portions 162a are supported by the support shaft 162b and are arranged at intervals so as to be divided in the width direction. That is, the post-fixing outer roller 162 is composed of a so-called dumpling roller. The roller portions 162a of this post-fixing outer roller 162 are arranged at positions overlapping with a target rib 303A and an add-on guide rib 500, which will be described in detail in the width direction when viewed from the conveyance direction. １ The post-fixing outer roller 162 is a driven roller that follows the post-fixing inner roller 161.

[0030] Furthermore, downstream of the branching section JN, the second transport path R2 has an upstream transport roller pair 180 and a downstream transport roller pair 190, as shown in Figures 1 and 3. Of these, the upstream transport inner roller 181 of the upstream transport roller pair 180 and the downstream transport inner roller 191 of the downstream transport roller pair 190 are positioned to be embedded in the guide surface of the second guide G2, as shown in Figure 3. Although not shown in Figure 3, the upstream transport outer roller 182 of the upstream transport roller pair 180 and the downstream transport outer roller 192 of the downstream transport roller pair 190 are positioned to be embedded in the guide surface of the third guide G3.

[0031] Next, the portion of the first guide G1 that forms the guide surface will be explained using Figures 3 to 4B. As shown in Figures 3 and 4B, the first guide G1 has, in order from upstream in the conveying direction, guide section G1A, guide section G1B, and guide section G1C as the portion that forms the guide surface. The fixed internal roller 161 is positioned between guide section G1A and guide section G1B in the conveying direction. Guide section G1A is positioned opposite the third guide G3 (see Figures 2A and 2B), and forms the first upstream conveying path R1a between it and the third guide G3. Guide section G1B and guide section G1C are connected to the flapper 300 as shown in Figures 2A and 4A. １ The flapper 300 is positioned opposite to the first position P1. １ The first transport path R1 is formed at the branching section JN between the two. In other words, the flapper 300 at the first position P1 １ This will form part of the first transport path R1.

[0032] As shown in Figures 3 and 4B, the guide portion G1B has multiple ribs G1BR arranged in the width direction as guide ribs. In this embodiment, cushioning members 600 made of sponge are arranged in three places on the guide portion G1B so as to fit between these ribs G1BR. These ribs G1BR are located at the flapper 300 at the second position P2. １The cushioning member 600 is positioned so that it partially overlaps with the rib 303 when viewed from the width direction. Further details regarding the position of the cushioning member 600 will be described later. The guide section G1B also forms a fourth guide section on the outer edges of the multiple ribs G1BR that can guide the sheet to the first transport path R1. The portion of this fourth guide section formed by the outer edges of the multiple ribs G1BR can be said to be a virtual surface connecting the outer edges of those ribs G1BR in the transport direction and the width direction. Here, sponge is used as an example of the cushioning member 600. However, the cushioning member 600 may be rubber or cloth. In other words, the cushioning member 600 can also be described as an elastic member that elastically deforms when the rib 303, which is the first rib, comes into contact with it. The cushioning member 600 can also be described as a damping member that dampens the movement of the flapper 300 when the rib 303 comes into contact with it.

[0033] Furthermore, the guide section G1C has a fifth guide section that can guide the sheet along the first transport path R1. Multiple (two) openings G1Ca are formed in this guide section G1C, and the rollers 230 are positioned in these openings G1Ca. The rollers 230 are rotatably supported by the first guide G1 by a rotating shaft (not shown) and rotate freely in contact with the sheet. As a result, as shown by the dashed line in Figure 2A, the sheet being transported by being pulled by the first discharge roller pair 210 comes into contact with the rollers 230, reducing the transport resistance compared to contacting the first guide G1.

[0034] [Flapper configuration] Next, the flapper 300 according to the first embodiment １ The detailed configuration will be explained using Figures 5 to 7. Figure 5 is a perspective view showing the side of the first guide portion of the flapper with the add-on guide rib attached. Figure 6 is a perspective view showing the side of the second guide portion of the flapper with the add-on guide rib attached. Figure 7 is a cross-sectional view showing the positional relationship between the add-on guide rib according to the first embodiment, the target rib to which it is attached (also called the rib to be attached), and the roller. Note that in Figure 7, the flapper 300 １ Add-on guide rib 500 １ This shows the one that has been attached, but the add-on guide rib 500 １ More details will be provided later, but here we will discuss the Flappa 300.１ The configuration will be explained.

[0035] Flapper 300 as a moving guide according to the first embodiment １ As shown in Figures 5, 6, and 7, it is roughly composed of a support shaft 301, a support portion 302, and a plurality of (22 in this embodiment) ribs 303. Also, the flapper 300 １ Between the widthwise Y-direction of the ribs 303, there are a plurality of ribs 304 (14 in this embodiment) that are smaller than the ribs 303 and are provided auxiliaryly on the side of the first guide portion 300A, which will be described in more detail later.

[0036] The support shaft 301 is positioned to penetrate the support portion 302 so as to protrude from the support portion 302 in the width direction (Y direction), and is fixed to the support portion 302 while being rotatably supported with respect to the second guide G2. That is, the flapper 300 is centered on the support shaft 301. １ The entire structure is configured to be rotatable and can be switched between a first position P1 and a second position P2 by a drive mechanism 900, which will be described later (see Figures 2A and 2B).

[0037] The support portion 302 is positioned so as to extend along the Y direction, which is the width direction in the axial direction of the support shaft 301. As shown in Figure 7, the support portion 302 is formed in a roughly triangular shape, which is generally slightly smaller than the rib 303 when viewed from the axial direction. Furthermore, the support portion 302 is an add-on guide rib 500 which will be described in more detail later as a mounting member. １ Gaflappa 300 １ It is designed to be attached as an add-on to the existing structure.

[0038] Each of the multiple ribs 303 is arranged in the width direction (Y direction), as shown in Figures 5 and 6, and is formed as a rib shape that protrudes from the support portion 302. Each rib 303 is formed in a roughly triangular shape, which is generally slightly larger than the support portion 302 when viewed from the width direction, as shown in Figure 7, and the acute-angled vertices of the triangle are formed to face upstream in the conveying direction. Of the multiple ribs 303, the target rib 303A, which will be adjacent to the add-on guide rib described in more detail later, has the same shape as the other ribs 303 and refers to the rib 303 that is positioned in the width direction at a selected position, as described later. The width direction position of the target rib 303A will be described later.

[0039] Thus, the add-on guide rib 500 １ The add-on guide rib 500 is attached to the target rib 303A by being attached to the support portion 302 so as to abut the target rib 303A. In the following description, among the multiple ribs 303, ribs other than the target rib 303A will also be referred to as the first rib. The add-on guide rib 500 is attached to the target rib 303A as the rib to be attached. １ The rib formed by this is also called the second rib 700. These first ribs and the target rib 303A are integrally formed with the support portion 302 and are arranged with a gap between them in the width direction.

[0040] Furthermore, as shown in Figure 5, each of the multiple ribs 304 is formed in a rib shape that protrudes from the support portion 302, so as not to protrude upstream in the conveying direction from the support portion 302, and to be at the same height as the adjacent rib 303.

[0041] Flappa 300 １ As shown in Figure 7, when at the first position P1 (see Figure 2A), it has a first guide section 300A (see Figure 5) that forms a part of the first transport path R1. Also, the flapper 300 １When in the second position P2 (see Figure 2B), it has a second guide section 300B that forms part of the second transport path R2 (see Figure 6). The first guide section 300A also has an upstream section 300Aa that is upstream in the transport direction and a downstream section 300Ab that is located downstream of the upstream section Aa in the transport direction. In this embodiment, the upstream section 300Aa is an add-on guide rib 500 which will be described later. １ In the case of ribs 303 that are not adjacent to each other, the first outer edge portion 303a is formed. Similarly, the downstream portion 300Ab is formed by the add-on guide rib 500, which will be described later. １ In the case of ribs 303 that are not adjacent to each other, the first outer edge portion 303a is formed. The upstream portion 300Aa is formed by the add-on guide rib 500 which is attached as will be described in more detail later. １ The third outer edge portion 500a is formed thereby. The downstream portion 300Ab is formed by the add-on guide rib 500 which will be described in more detail later. １ Then, it is formed by the third outer edge portion 500a.

[0042] Specifically, as shown in Figures 5 and 7, the rib 303 has a first outer edge portion 303a on the side of the first guide portion 300A at its outer edge. In other words, the flapper 300 is at the first outer edge portion 303a １ The first outer edge portion 303a forms a first guide portion 300A and also forms a part of the first transport path R1 on which the sheet can be guided. The first outer edge portion 303a has, when viewed from the width direction, a curved portion 303ab that curves inward in a concave shape, and straight portions 303aa and 303ac that extend in a straight line. As a result, when the sheet is in the first position P1 (see Figure 2A), the first outer edge portion 303a first guides the leading edge of the sheet being transported from below by contacting it at a gentle angle with the straight portion 303aa. After that, the first outer edge portion 303a changes the angle of the leading edge of the sheet with the curved portion 303ab so that it faces the direction of the first discharge roller pair 210. The leading edge of the sheet is then guided toward the first discharge roller pair 210 while moving away from the straight portion 303ac. Furthermore, the portion formed by the first outer edges 303a of the multiple ribs 303 in the first guide section 300A can be described as a virtual plane connecting these first outer edges 303a in the conveying direction and the width direction.

[0043] On the other hand, the rib 303 has a second outer edge portion 303b on the side of the second guide portion 300B at its outer edge, and as shown in Figures 6 and 7, it extends over the entire outside of the main body portion 302A in the conveying direction. In other words, the second guide portion 300B, which forms part of the second conveying path R2, is the add-on guide rib 500 which will be described later. １ In the case of ribs 303 that are not adjacent to each other, the second outer edge portion 303b of the rib 303 is formed. In other words, when the sheet is transported to the second transport path R2, it is configured so that the sheet does not come into contact with the support portion 302 as much as possible. The second guide portion 300B is formed by the add-on guide rib 500 which is attached as will be described in more detail later. １ Then, it is formed by the fourth outer edge portion 500b.

[0044] As shown in Figure 7, the second outer edge portion 303b has, when viewed from the width direction, a first straight portion 303ba which is located upstream in the conveying direction, and a second straight portion 303bb which is continuously connected to the first straight portion 303ba and located downstream of the first straight portion 303ba in the conveying direction. This allows the flapper 300 １ When the guide is in the second position P2, the second outer edge portion 303b guides the leading edge of the sheet being transported from below upward while contacting the first straight portion 303ba and the second straight portion 303bb. The portion of the second guide portion 300B formed by the second outer edge portions 303b of the multiple ribs 303 can also be said to be a virtual plane connecting these second outer edge portions 303b in the transport direction and width direction.

[0045] The flapper 300 is configured in the shape described above. １ It is formed from, for example, plastic resin, to reduce weight. Furthermore, by forming multiple ribs 303 from the support portion 302 and configuring their outer edges to abut the sheet, a so-called comb-shaped sheet guide portion is formed, which is lighter than, for example, configuring the sheet to be guided by the outer surface of the support portion 302. Consequently, the switching control by the drive mechanism 900 described later can be accelerated, contributing to improved productivity of the printer 100.

[0046] [Configuration of the flapper drive mechanism] Next, the flapper 300 １ A drive mechanism 900 that switches between a first position P1 and a second position P2 will be explained with reference to Figure 8. Figure 8 is a cross-sectional view showing the drive mechanism of the flapper.

[0047] As shown in Figure 8, the flapper 300 １ The drive mechanism 900 that drives and controls the switching of the flapper 300 comprises a solenoid 901 having a plunger 902, a first arm 904, a second arm 907, and a spring 908. The solenoid 901 drives the plunger 902 in the direction of the arrow U, which is upward in the figure, when energized by a command from a control unit (not shown). The first arm 904 is rotatably supported at one end on a pivot shaft 903, and an engagement shaft 906 is fixed to the other end, with a hook 904A formed thereon to which one end of the spring 908 is connected, and further connected to the plunger 902 by a connecting shaft 905 near the center. The other end of the spring 908 is fixed to the frame (i.e., the printer body 101) that supports the drive mechanism 900. The second arm 907 has one end attached to the flapper 300. １ The shaft is fixed to the support shaft 301 and has an elongated hole 907A formed at its other end, into which the engagement shaft 906 is slidably engaged.

[0048] In this configuration, the drive mechanism 900, controlled by a control unit (not shown), has the plunger 902 of the solenoid 901 not driven, and the biasing force of the spring 908 causes the first arm 904 and the second arm 907 to be in a downward position. In this state, the second arm 907, to which the support shaft 301 is fixed, is also in a downward position, so the flapper 300 １ The first arm 904 is controlled to the first position P1 (see Figure 2A). When the plunger 902 of the solenoid 901 is driven upward in the direction of arrow U by the control of a control unit (not shown), the first arm 904 is driven upward in the direction of arrow V against the biasing force of the spring 908, and the second arm 907 is also rotated upward by the engagement shaft 906. As a result, the flapper 300 fixed to the second arm 907 １ The support shaft 301 is rotated, and the flapper 300 １It is controlled to the second position P2 (see Figure 2B).

[0049] [Configuration of the add-on guide rib] Next, the add-on guide rib 500 as a sliding member according to the first embodiment １ The structure of the add-on guide rib 500 will be explained using Figures 5 to 7. １ is Flappa 300 １ It is a part that can be retrofitted to the flapper 300. １ It is formed of a material that has higher sliding properties with the sheet than the material of the rib 303. For example, add-on guide rib 500 １ It is formed from fluoropolymer (PFA).

[0050] As shown in Figures 5 and 6, the add-on guide rib 500 １ It is positioned adjacent to the target rib 303A among the multiple ribs 303. Add-on guide rib 500 １ As shown in Figure 7, it is attached to the target rib 303A by being attached to the support portion 302 adjacent to the target rib 303A. The support portion 302 has a plate-shaped main body portion 302A that is triangular when viewed from the width direction, as described above. This main body portion 302A also serves as the main body portion of the flapper 300 as a moving guide, and the add-on guide rib 500 １ It has a claw portion 500c that engages with one end 302Aa of the main body portion 302A, and a claw portion 500d that engages with the other end 302Ab. This allows the add-on guide rib 500 １ The add-on guide rib 500 is attached to the support portion 302 by elastically deforming the claw portions 500c and 500d in the direction of transport from upstream to downstream (from bottom to top in Figure 7) and engaging with it in a hooking manner. １ is Flappa 300 １ The claws 500c and 500d are deformed to release the snag, and the flapper 300 １ It can also be removed from it. In other words, the add-on guide rib 500 １ is Flappa 300 １ It is detachable.

[0051] In this embodiment, the add-on guide rib 500 １ Flapper 300 １ The description explains how to attach the support part 302 to the conveying direction from upstream to downstream, but it is not limited to this. In other words, the flapper 300 １ For example, if the sheet is installed in a reverse flow direction, from downstream to upstream in the conveying direction, there is a risk of it coming off due to collision. Therefore, the installation direction should be different from the reverse flow direction (a direction other than the reverse flow direction) to reduce the possibility of it coming off.

[0052] Add-on guide for the RIBB 500 according to this embodiment １ When attached to the main body 302A adjacent to the target rib 303A in this manner, its outer edge becomes outside the outer edge of the target rib 303A. That is, the add-on guide rib 500 １ The third outer edge portion 500a on the outer edge of the rib 303A is substantially the same shape (similar shape) as the first outer edge portion 303a of the target rib 303A, and is configured to be located outside the first outer edge portion 303a. In other words, the third outer edge portion 500a is positioned outside the straight portion 303aa, the curved portion 303ab, and the straight portion 303ac of the first outer edge portion 303a. That is, the add-on guide rib 500 １ The upstream end in the sheet transport direction is located further upstream in the sheet transport direction than the upstream end in the sheet transport direction of the target rib 303A. As a result, the third outer edge portion 500a is located on the flapper 300 １ The third guide section guides the sheet to the first transport path R1 when it is in the first position P1. The portion formed by the third outer edges 500a of the multiple ribs 303 that constitute the third guide section can also be said to be a virtual plane connecting these third outer edges 500a in the transport direction and the width direction.

[0053] Similarly, add-on guide rib 500 １The fourth outer edge portion 500b on the outer edge of the flapper 300 has the same shape (similar shape) as the second outer edge portion 303b of the target rib 303A, and is configured to be located outside the second outer edge portion 303b. In other words, the fourth outer edge portion 500b is positioned along the first straight portion 303ba and the second straight portion 303bb, and is located outside of them. As a result, the fourth outer edge portion 500b is located outside the flapper 300 １ The fourth guide section guides the sheet to the second transport path R2 when it is in the second position P2. The portion formed by the fourth outer edge portions 500b of the multiple ribs 303 that constitute the fourth guide section can also be said to be a virtual plane connecting these fourth outer edge portions 500b in the transport direction and width direction.

[0054] In short, the third outer edge portion 500a is an add-on guide rib 500 １ This is the portion that forms part of the first transport path R1 at the outer edge of the flapper 300. １ It forms part of the first guide portion 300A. Furthermore, the fourth outer edge portion 500b is an add-on guide rib 500 １ This is the part that forms part of the second transport path R2 at the outer edge of the flapper 300. １ It forms the second guide portion 300B.

[0055] The add-on guide rib 500 is configured in this way. １ The flapper 300 is adjacent to the target rib 303A. １ Let's assume it's attached to it. Then, Flapper 300 １ When the sheet is in the first position P1 and guided along the first transport path R1, the add-on guide rib 500 is shown by the solid line in Figure 2A. １ The tip of the sheet comes into contact with the third outer edge 500a of the add-on guide rib 500, and no longer comes into contact with the first outer edge 303a of the target rib 303A. As a result, when the sheet is guided along the first transport path R1, the tip of the sheet comes into contact with the add-on guide rib 500, which is made of a high-sliding material. １ Because it is guided by contact with it, the risk of defects or streaks forming on the sheet can be reduced. And the add-on guide rib 500 １ The sheet, which is guided in contact with the third outer edge 500a, is guided along the first transport path R1 toward the first discharge roller pair 210, as shown by the dotted line in Figure 2A.

[0056] Also, Flappa 300 １ When the sheet is in the second position P2 and guided to the second transport path R2, the add-on guide rib 500 is as shown by the solid line in Figure 2B. １ The tip of the sheet contacts the fourth outer edge 500b of the add-on guide rib 500, but does not contact the second outer edge 303b of the target rib 303A. As a result, even when the sheet is guided along the second transport path R2, the sheet does not come into contact with the add-on guide rib 500, which is a high-sliding material. １ Because it is guided by contact with it, the risk of defects or streaks forming on the sheet can be reduced. And the add-on guide rib 500 １ The sheet, which is guided in contact with the fourth outer edge 500b, is guided along the second transport path R2 toward the second discharge roller pair 220 (see Figure 1), as shown by the dotted line in Figure 2B.

[0057] In the above-described embodiment, the entire add-on guide rib 5001 was configured to be larger than the target rib 303A, and the sheet guide surface of the second rib 700, which is formed by the add-on guide rib 5001 and the target rib 303A, was formed by the outer edge of the add-on guide rib 5001. However, the embodiment is not limited to this. The add-on guide rib 5001 only needs to constitute at least a part of the sheet guide surface of the second rib 700, and a part of this sheet guide surface may be formed by the outer edge of the target rib 303A. For example, on the first surface of the sheet guide surface facing the first guide, the downstream portion in the sheet transport direction may be curved, and only this downstream portion of the first surface may be formed by the outer edge of the add-on guide rib 5001, while the upstream portion of the first surface may be formed by the outer edge of the target rib 303A. In other words, the upstream portion of the first surface may be configured so that the add-on guide rib 5001 does not exist. Furthermore, in the embodiment described above, the add-on guide rib 5001 was attached to the target rib 303A in a widthwise contact manner. However, for example, the add-on guide rib 5001 may be attached to the target rib 303A in such a manner that it covers at least a portion of the outer edge of the target rib 303A.

[0058] Furthermore, the add-on guide rib 500 is configured as described above. １It is not attached to all the ribs 303, but only to the target rib 303A. As a result, the add-on guide rib 500 １ prevents the flapper 300 １ from becoming unnecessarily heavy due to its attachment.

[0059] Also, as described above, the add-on guide rib 500 １ is arranged at a position overlapping with the roller portion 162a of the outer roller 162 after fixing in the width direction when viewed from the conveyance direction. That is, the sheet conveyed by the roller portion 162a of the outer roller 162 after fixing arranged immediately upstream in the conveyance direction of the flapper 300 １ contacts the add-on guide rib 500 １ [[ID=1--3]] rather than the rib 303. Thus, it is possible to reduce the risk that the sheet conveyed by the roller portion 162a of the outer roller 162 after fixing is pressed against the rib 30 and defects or streaks are formed in the sheet.

[0060] [Position relationship between add-on guide rib and roller] Next, the position relationship between the add-on guide rib 500 １ attached to the flapper 300 according to the first embodiment １ and the roller 230 arranged in the first conveyance path R1 will be described. As described above, the plurality of rollers 230 are arranged at two positions in the width direction so as to protrude from the opening G1Ca of the guide portion G1C of the first guide G1 as shown in FIGS. 3 and 4B. And the target rib 303A arranged near the center in the width direction and the add-on guide rib 500[[ID=__1]] １ attached adjacent to the target rib 303A are arranged close to the roller as shown in FIGS. 4A and 4B. Therefore, the sheet passing near the flapper 300 １ rather than the rib 303 in the first conveyance path R1 by the roller 230 is more easily slid on the add-on guide rib 500 １ having higher slidability than the rib 303. This can reduce the risk that defects or streaks are formed in the sheet guided by the roller 230.

[0061] Also, as shown in FIGS. 2A and 7, in the downstream portion 300Ab facing the roller 230, the third outer edge portion 500a is also disposed outside the first outer edge portion 303a of the rib 303. Therefore, when the flapper 300 １ is in the first position P1, the sheet guided by the roller 230 can slide on the add-on guide rib 500 ２ Accordingly, the sheet passing near the flapper 300 rather than the guide portion G1C of the first guide G1 in the first conveyance path R1 by the roller 230 can be more easily slid on the add-on guide rib 500 １ having higher slidability than the first outer edge portion 303a of the rib 303. This can reduce the risk of defects and streaks forming in the sheet guided by the roller 230.

[0062] Note that, as shown in FIGS. 4A and 4B, the roller 230 can be said to be on the outer side in the width direction compared with the second rib 700 on the central side, but on the inner side in the width direction compared with the second rib 700 on the end side. In other words, the second rib 700 on the central side can be said to be on the inner side in the width direction compared with the roller 230, and the second rib 700 on the end side can be said to be on the outer side in the width direction compared with the roller 230.

[0063] [Position relationship between add-on guide rib and buffer member] Next, the position relationship between the add-on guide rib 500 １ and the buffer member 600 will be described. As described above, if the add-on guide rib 500 １ is attached to all the ribs 303, the flapper 300 １ may become heavy, which may deteriorate the productivity of the printer 100. Therefore, as shown in FIGS. 5 and 6, in the present embodiment, the add-on guide rib 500 １ ​​These are attached. Two of these four target ribs 303A are positioned so that their edges are slightly inside the smallest width size that can be printed by the printer 100 (for example, postcard size). The other two of these four target ribs 303A are positioned so that their edges are slightly inside the largest width size that can be printed by the printer 100 (for example, A4 size). In other words, out of the 22 ribs 303, four target ribs 303A are selected according to the smallest and largest sheet sizes.

[0064] On the other hand, as shown in Figures 3, 4A, and 4B, as described above, a plurality of ribs G1BR are formed in the guide portion G1B of the first guide G1, aligned in the width direction. Furthermore, cushioning members 600 made of sponge or the like are arranged at three locations in the width direction, spaced apart, so as to fit between these ribs G1BR. These cushioning members 600 are as shown in Figure 2B, flapper 300 １ When it is switched to the second position P2, the flapper 300 １ The rib 303 of the flapper 300 comes into contact (collides) with the flapper 300, for example. １ This prevents noise from being generated by a direct collision with the first guide G1.

[0065] As shown in Figure 4A, these cushioning members 600 are positioned to contact a rib 303 different from the target rib 303A. In other words, among the multiple ribs 303, the rib offset in the width direction (Y direction) from the position where the cushioning member 600 is positioned is selected as the target rib 303A. The target rib 303A whose position has been selected in the width direction in this way is the flapper 300 １ Even when switched to the second position P2, the cushioning member 600 is in a different position in the width direction. In other words, the add-on guide rib 500 attached to the target rib 303A １ The cushioning member 600 is positioned at a location offset in the width direction from the flapper 300. １ When the add-on guide rib 500 is switched to the second position P2, １ The flapper 300 does not come into contact with the cushioning member 600. １When the add-on guide rib 500 is switched to the second position P2, １ This avoids the increase in noise caused by contact between the flapper 300 and the buffer member 600, that is, the flapper 300 １ This reduces noise during switching. Add-on guide rib 500 １ An example was given in which the cushioning member 600 is positioned so as to abut against one rib 303 different from the target rib 303A without contacting the other rib 303A. However, for example, the cushioning member 600 may be positioned against the add-on guide rib 500. １ To avoid contact with the other rib, it may be positioned to be in contact with two adjacent ribs 303 simultaneously.

[0066] <Second Embodiment> Next, a second embodiment, which is a modified version of the first embodiment, will be described with reference to Figure 9. Figure 9 is a cross-sectional view showing the positional relationship between the add-on guide rib according to the second embodiment, the target rib on which it is attached, and the roller. In this description of the second embodiment, the same reference numerals as in the first embodiment will be used for the same parts, and their descriptions will be omitted.

[0067] In this second embodiment, the add-on guide rib 500 according to the first embodiment １ In comparison, Add-on Guide Rib 500 ２ This is a modified version of the shape. In detail, as shown in Figure 9, the add-on guide rib 500 according to the second embodiment ２ is Flappa 300 １ In the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ２ The third outer edge portion 500a is positioned on the inside. In other words, in the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ２ The flapper 300 is greater than the third outer edge 500a １ The rib 303 is on the outside, and the straight portion 303ac, which is the outer edge of the rib 303, is formed to extend downstream in the conveying direction.

[0068] Add-on guide rib 500 １ The sheet, which is guided in contact with the third outer edge 500a of the flapper 300, is guided along the first transport path R1 toward the first discharge roller pair 210, as shown by the dotted line in Figure 2A.１ On the outside of the straight section 303ac of rib 303, there is an add-on guide rib 500. １ The third outer edge portion 500a is not provided. That is, the rear end of the sheet conveyed by the first discharge roller pair 210 is located at four add-on guide ribs 500 in the width direction. １ If it is only slid in that direction, there is a risk that streaks may be formed. However, the rear end of this sheet is conveyed by the straight sections 303ac of multiple (22) ribs 303 (including the target rib 303A), that is, by four add-on guide ribs 500 １ Rather than the rear end of the sheet sliding, the force at contact is distributed. Therefore, the risk of streaks being formed on the sheet is reduced, and the flow of the sheet conveyed by the first discharge roller pair 210 can be improved.

[0069] Furthermore, on the outside of this downstream section 300Ab, there is an add-on guide rib 500. １ The third outer edge portion 500a is not positioned. By configuring it in this way, the add-on guide rib 500 １ Flapper 300 １ During the assembly process when attaching it, the add-on guide rib 500 １ By causing the rollers to collide with the roller 230, the risk of damaging each other can be reduced, thus improving ease of assembly.

[0070] <Third Embodiment> Next, a third embodiment, which is a modified version of the first and second embodiments described above, will be explained with reference to Figure 10. Figure 10 is a cross-sectional view showing the positional relationship between the add-on guide rib according to the third embodiment, the target rib on which it is attached, and the roller. In this explanation of the third embodiment, the same reference numerals are used for parts similar to those in the first and second embodiments, and their explanations are omitted.

[0071] In this third embodiment, the add-on guide rib 500 according to the first embodiment １ In comparison, Add-on Guide Rib 500 ３ This is a modified version of the shape. In detail, as shown in Figure 10, the add-on guide rib 500 according to the third embodiment ３ is Flappa 300 １In the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ３ The third outer edge portion 500a is positioned on the outside. On the other hand, the add-on guide rib 500 ３ is Flappa 300 １ The upstream portion 300Aa of the first guide portion 300A is positioned inward from the first outer edge portion 303a (straight portion 303aa and curved portion 303ab) of the target rib 303A.

[0072] Therefore, Flapper 300 １ When the sheet is in the first position P1, the leading edge of the sheet being conveyed by the fixed roller pair 160 comes into contact with the first outer edge 303a of all the ribs 303 (including the target rib 303A) that can come into contact in the width direction. Therefore, in the configuration of this third embodiment, the force of contact is distributed more evenly than when the leading edge of the sheet comes into contact with the four add-on guide ribs 500 as in the first embodiment, and the occurrence of damage to the leading edge of the sheet can be reduced.

[0073] Also, add-on guide rib 500 ３ In this embodiment, similar to the second embodiment, the flapper 300 １ In the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ３ The third outer edge 500a is positioned outward. Therefore, the sheet guided by the roller 230 is on the add-on guide rib 500. ３ It is slidable. Therefore, the roller 230 allows the flapper 300 to move further than the guide portion G1C of the first guide G1 in the first transport path R1. １ The sheet that will pass near the first outer edge 303a of the rib 303 is guided by the add-on guide rib 500, which has a higher sliding surface than the first outer edge 303a of the rib 303. ３ This makes it easier to slide. As a result, the risk of defects or streaks forming on the sheet guided by the roller 230 can be reduced.

[0074] Furthermore, the add-on guide rib 500 according to this third embodiment ３ is Flappa 300 １On the side of the second guide portion 300B, it is positioned so that it is generally outside the second outer edge portion 303b of the target rib 303A. However, it is not limited to this, and upstream of the second guide portion 300B in the transport direction, the add-on guide rib 500 is positioned outside the second outer edge portion 303b. ３ The fourth outer edge portion 500b may be configured to be positioned on the inside. This allows the flapper 300 １ When the sheet is in the second position P2, the leading edge of the sheet being transported by the fixed roller pair 160 comes into contact with the second outer edge 303b of all ribs 303 (including the target rib 303A) that can come into contact in the width direction. With this configuration, the force of contact is distributed more evenly than when the leading edge of the sheet comes into contact with the four add-on guide ribs 500 as in the first embodiment, and the occurrence of damage to the leading edge of the sheet can be reduced.

[0075] <Fourth Embodiment> Next, a fourth embodiment, which is a modified version of the first to third embodiments described above, will be explained with reference to Figure 11. Figure 11 is a cross-sectional view showing the positional relationship between the add-on guide rib according to the fourth embodiment, the target rib on which it is attached, and the roller. In this explanation of the fourth embodiment, the same reference numerals as in the first to third embodiments will be used for the same parts, and their explanations will be omitted.

[0076] In this fourth embodiment, the flapper 300 according to the first to third embodiments １ In comparison, Flappa 300 ２ This is a modified version of the original. Also, the Flappa 300 ２ Add-on guide rib 500 to match the shape ４ The shape has also been changed.

[0077] In detail, as shown in Figure 11, the flapper 300 according to the fourth embodiment ２ When viewed from the width direction, the upstream portion 300Aa of the first guide portion 300A is formed in a straight line, and the downstream portion 300Ab is formed in a concave curved shape. That is, the first outer edge portion 303a of the rib 303 has, when viewed from the width direction, a straight portion 303ad formed in a straight line upstream in the conveying direction, and a curved portion 303ae formed in a concave shape downstream in the conveying direction.

[0078] Furthermore, the add-on guide rib 500 according to the fourth embodiment ４ The third outer edge portion 500a has, when viewed from the width direction, a straight portion 500aa formed in a straight line upstream in the conveying direction and a curved portion 500ab formed in a concave shape downstream in the conveying direction. That is, flapper 300 ２ In the upstream portion 300Aa of the first guide section 300A, the add-on guide rib 500 ４ The straight section 500aa is positioned inward from the straight section 303ad of the first outer edge 303a of the target rib 303A. Also, the flapper 300 ２ In the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ２ The curved portion 500ab is positioned outside the curved portion 303ae of the first outer edge portion 303a of the target rib 303A.

[0079] Therefore, Flapper 300 １ When the sheet is in the first position P1, the leading edge of the sheet being conveyed by the fixed roller pair 160 comes into contact with the straight portion 303ad of the first outer edge 303a of all ribs 303 (including the target rib 303A) that can come into contact in the width direction. Therefore, in the configuration of this fourth embodiment, the force of contact is distributed more evenly than when the leading edge of the sheet comes into contact with the four add-on guide ribs 500 as in the first embodiment, and the occurrence of damage to the leading edge of the sheet can be reduced.

[0080] Then, the leading edge of the sheet that has come into contact with the straight portion 303ad of the first outer edge 303a of the rib 303 (including the target rib 303A) is transported further, and the add-on guide rib 500 ４ Add-on guide for Rib 500 ２ The sheet slides along the curved portion 500ab. This guides the sheet smoothly toward the first discharge roller pair 210.

[0081] Furthermore, add-on guide rib 500 ４ In this case, similar to the second and third embodiments, the flapper 300 ２ In the downstream portion 300Ab of the first guide portion 300A, the add-on guide rib 500 ４The curved portion 500ab of the third outer edge 500a is positioned outward. Therefore, the sheet guided by the roller 230 is on the add-on guide rib 500 ４ It is slidable. Therefore, the roller 230 allows the flapper 300 to move further than the guide portion G1C of the first guide G1 in the first transport path R1. ２ The sheet that will pass near the curved portion 303ae of the target rib 303A will be guided by the add-on guide rib 500, which has a higher sliding surface than the curved portion 303ae of the target rib 303A. ４ This makes it easier to slide. As a result, the risk of defects or streaks forming on the sheet guided by the roller 230 can be reduced.

[0082] <Fifth Embodiment> Next, a fifth embodiment, which is a modified version of the second embodiment described above, will be explained with reference to Figure 12. Figure 12 is a cross-sectional view showing the positional relationship between the add-on guide rib according to the fifth embodiment, the target rib on which it is attached, and the roller. In this explanation of the fifth embodiment, the same reference numerals as in the second embodiment will be used for the same parts, and their explanations will be omitted.

[0083] In this fifth embodiment, the flapper 300 １ This involves changing the relative positional relationship between the roller 230 and the guide. For example, an opening can be formed in the guide portion G1B of the first guide G1 (see Figure 3), and the roller 230 can be positioned to protrude from the guide portion G1B.

[0084] In this configuration, as shown in Figure 12, the roller 230 is connected to the flapper 300. １ It will be positioned opposite the upstream part 300Aa of the first guide part 300A. Therefore, the flapper 300 １ When the first position P1, the seat guided by the roller 230 is the add-on guide rib 500 １ The third outer edge 500a is slidable. Therefore, the roller 230 allows the flapper 300 to move further than the guide portion G1B of the first guide G1 in the first transport path R1. １ The sheet that will pass near the first outer edge 303a of the target rib 303A will be guided by the add-on guide rib 500, which has a higher sliding surface than the first outer edge 303a of the target rib 303A. １This makes it easier to slide. As a result, the risk of defects or streaks forming on the sheet guided by the roller 230 can be reduced.

[0085] Also, Flappa 300 １ In the downstream section 300Ab of the first guide section 300A, the add-on guide rib 500 １ The third outer edge 500a is not formed, and the sheet is guided by sliding along the first outer edge 303a of the rib 303. In this case, since the roller 230 does not face the straight portion 303ac of the first outer edge 303a of the rib 303, the sheet does not pass as close to it as, for example, when the roller 230 is arranged facing each other. For this reason, the add-on guide rib 500 １ Even if the sliding properties of the first outer edge 303a of the rib 303 are lower than those of the other rib, the risk of defects or streaks forming in the sheet is reduced.

[0086] Furthermore, the add-on guide rib 500 shown in the first embodiment １ In this case, the roller 230 is connected to the flapper 300. １ It may also be positioned opposite the upstream portion 300Aa of the first guide portion 300A.

[0087] <Possibility of other embodiments> In the first to fifth embodiments described above, the add-on guide rib 500 was positioned adjacent to the target rib 303A, and the outer edge of the add-on guide rib 500 was configured to be outside the outer edge of the target rib 303A. However, the invention is not limited to this configuration, and the add-on guide rib may be configured to be attached (connected) to the target rib so as to cover the outer edge of the target rib. １ The entire structure does not need to have high sliding properties. In other words, the add-on guide rib 500 １ At least the third outer edge portion 500a that is in contact with the sheet is the flapper 300 １ It is sufficient if the material has better sliding properties with the sheet than the material itself. Also, add-on guide rib 500 １ As an example, a component with high sliding properties was given. However, the add-on guide rib 500 １ It is not necessarily the Flappa 300 １It does not have to be a component with higher sliding properties. In other words, the add-on guide rib 500 １ is Flappa 300 １ Any device that, when attached to the seat, can provide a stable seat guide or reduce damage to the seat would suffice.

[0088] Furthermore, in the first to fifth embodiments, an arrangement was described in which the add-on guide ribs 500 (target ribs 303A) were placed at four locations in the width direction, and the cushioning members 600 were placed at three locations in the width direction, and these were arranged to be offset from each other. However, the number and arrangement of these can be any number and any arrangement. In other words, as long as the add-on guide ribs 500 and the cushioning members 600 do not come into contact (collide) with each other when the flapper 300 is switched, and the ribs 303 and the cushioning members 600 come into contact, the number and arrangement can be any.

[0089] Furthermore, in the first to fifth embodiments, a structure was described in which the add-on guide rib 500 is attached to the flapper 300 by hooking the claw portions 500c and 500d onto the main body portion 302A of the support portion 302 of the flapper 300. However, the structure is not limited to this, and it may also be attached using an elastically deformable structure such as a snap-fit, or even by bonding with an adhesive.

[0090] Furthermore, in the first to fifth embodiments, the add-on guide rib 500 was described as having a third outer edge portion 500a and a fourth outer edge portion 500b, that is, sliding with the sheet at both the first guide portion 300A and the second guide portion 300B of the flapper 300. However, it is not limited to this, and for example, the add-on guide rib 500 may have only one of the third outer edge portion 500a and the fourth outer edge portion 500b. In other words, the add-on guide rib 500 only needs to form at least one of the following: a third outer edge portion 500a that can guide the sheet to the first transport path R1 when it is in the first position P1, and a fourth outer edge portion 500b that can guide the sheet to the second transport path R2 when it is in the second position P2.

[0091] Furthermore, in the first to fifth embodiments, a flapper 300 was described in which a plurality of ribs 303 have a first outer edge portion 303a and a second outer edge portion 303b, that is, the flapper 300 is slidable with the sheet at both the first guide portion 300A and the second guide portion 300B. However, it is not limited to this, and for example, a rib 303 may have only one of the first outer edge portion 303a and the second outer edge portion 303b. In other words, the flapper 300 only needs to have a first outer edge portion 303a that can guide the sheet to the first transport path R1 when it is in the first position P1, and a second outer edge portion 303b that can guide the sheet to the second transport path R2 when it is in the second position P2, formed by the outer edges of at least a plurality of ribs 303.

[0092] Furthermore, in the first, third to fifth embodiments, a case was described in which the third outer edge 500a of the add-on guide rib 500 is located outward from a part of the first guide portion 300A (first outer edge portion 303a) of the flapper 300. Specifically, in the first and fifth embodiments, a case was described in which the third outer edge 500a of the add-on guide rib 500 is located outward from the upstream portion 300Aa (first outer edge portion 303a of the rib 303) of the first guide portion 300A of the flapper 300. Furthermore, in the third and fourth embodiments, a case was described in which the third outer edge 500a of the add-on guide rib 500 is located outward from the downstream portion 300Ab of the first guide portion 300A of the flapper 300. However, the part of the first guide portion 300A is not limited to either the upstream portion 300Aa or the downstream portion 300Ab. For example, the third outer edge 500a of the add-on guide rib 500 may be shaped such that it is positioned outside the first guide section 300A at two or more locations in the transport direction. Also, the boundary between the upstream section 300Aa and the downstream section 300Ab may be at any position; in other words, the portion where the third outer edge 500a of the add-on guide rib 500 is located on the outside may be defined as the upstream section 300Aa or the downstream section 300Ab. Furthermore, if the third outer edge 500a of the add-on guide rib 500 is located outside the upstream section 300Aa, it may also protrude outside a part of the downstream section 300Ab. In other words, in this case, the third outer edge 500a of the add-on guide rib 500 should be positioned outside the upstream section 300Aa when viewed from the width direction, and not positioned outside at least a part of the downstream section 300Ab. Similarly, if the third outer edge 500a of the add-on guide rib 500 is located outside the downstream portion 300Ab, the third outer edge 500a of the add-on guide rib 500 may also protrude outside a portion of the upstream portion 300Aa. In other words, in this case, the third outer edge 500a of the add-on guide rib 500 should be positioned outside the downstream portion 300Ab when viewed from the width direction, and not positioned outside at least a portion of the upstream portion 300Aa.

[0093] Furthermore, in the first to fifth embodiments, the first transport path R1 is a transport path toward the first discharge roller pair 210, and the second transport path R2 is a transport path toward the second discharge roller pair 220, meaning that the first transport path R1 is located below the second transport path R2. However, these relationships may be reversed, and furthermore, for example, one of the first and second transport paths may be a transport path that discharges the sheet to the outside of the printer 100, and the other may be a re-transport path that re-transports the sheet to the image forming unit 102. In other words, the first and second transport paths may be any type of transport path, and the flapper 300 may be located at any branch of the transport path.

[0094] Furthermore, in the first to fifth embodiments, the buffer member 600 was described as being positioned to collide with the rib 303 when the flapper 300 is switched to the second position P2. However, the invention is not limited to this, and the buffer member may be positioned to collide with the rib 303 when the flapper 300 is switched to the first position P1. Moreover, the buffer member may be positioned on both sides of the rotational direction of the flapper 300 when viewed from the width direction, so as to collide with the rib 303 regardless of which position the flapper 300 is switched to.

[0095] Furthermore, in the first to fifth embodiments, the drive mechanism 900 was described in which the flapper 300 is biased to a first position P1 by the biasing force of a spring 908 and switched to a second position P2 by the drive of a solenoid 901. However, it is not limited to this, and it is also acceptable for the flapper 300 to be biased to a second position P2 by the biasing force of a spring 908 and switched to a first position P1 by the drive of a solenoid 901. In particular, in this case, the cushioning member may be positioned to collide with the rib 303 when the flapper 300 is switched to the first position P1.

[0096] Furthermore, in the first to fifth embodiments, the target rib 303A was described as being positioned in close proximity to the roller 230, but this proximity does not necessarily mean that there are no other ribs 303 in between. That is, the target rib 303A can be any rib adjacent to the roller 230 in the width direction, or any rib positioned close by one or more ribs in between.

[0097] Furthermore, in the first to fifth embodiments, when positioned at the second position, the flapper 300 is viewed from the width direction. １ An example of an arrangement in which the roller 230 does not overlap was shown. However, when the second position is located, the flapper 300 is viewed from the width direction. １ The roller 230 may be arranged to overlap. When viewed from the width direction, the flapper 300 １ In this case, where the rollers 230 and the ribs 303 overlap, one roller 230 should be positioned between two of the multiple ribs 303 in the width direction. Also, in this case, when viewed from the width direction, the flapper 300 １ The add-on guide ribs attached to the roller also overlap with the roller 230. The roller 230 is positioned between the target rib 303A (the rib adjacent to the add-on guide rib or the rib to which the add-on guide rib is joined) and the rib adjacent to the target rib. In this case, it is preferable that the roller 230 and the target rib are adjacent in the width direction, that is, that there is no other rib 303 between the roller 230 and the target rib in the width direction. In other words, it is preferable that the roller 230 and the add-on guide rib are adjacent in the width direction, that is, that there are no multiple ribs positioned between the roller 230 and the add-on guide rib in the width direction.

[0098] Furthermore, in the first to fifth embodiments, the sheet transport unit 104, as an example of a sheet transport device, was described as being located downstream of the image forming unit 102 in the transport direction and transporting the sheet to the outside of the printer 100. However, it is not limited to this, and any sheet transport device that transports sheets is acceptable. That is, the sheet transport device may be, for example, the part that supplies the sheet to the image forming unit. Moreover, the sheet transport device may be, for example, the part that transports sheets in a large-capacity feeding deck, inspection device, finisher, reversing device, binding device, bookbinding device, folding device, cutting device, perforation device, etc., or the device itself. The disclosures described in the embodiments above may be combined in any way.

[0099] The present invention can be used in sheet transport devices and image forming devices.

[0100] The present invention is not limited to the embodiments described above, and various modifications and variations are possible without departing from the spirit and scope of the invention. Accordingly, the following claims are attached to make the scope of the invention public.

[0101] This application claims priority based on Japanese Patent Application No. 2024-232526, filed on 27 December 2024, and all of its contents are incorporated herein by reference.

[0102] 100...Printer (image forming apparatus) / 102...Image forming unit / 104...Sheet transport unit (sheet transport device) / 150...Fuser (transport unit) / 160...Post-fusing roller pair (transport unit) / 162...Post-fusing outer roller (upstream roller) / 162a...Roller part (contact rotating part) / 162b...Support shaft / 180...Upstream transport roller pair (transport unit) / 190...Downstream transport roller pair (transport unit) / 210...First discharge roller pair (transport unit) / 220...Second discharge roller pair (transport unit) / 230...Roller (rotating body) / 300...Flapper (movement guide) / 300A...First guide unit / 300Aa...Upstream Section / 300Ab... Downstream section / 300B... Second guide section / 302... Support section / 303... Rib (first rib) / 303A... Target rib (rib to be mounted) / 303ab... Curved section / 303aa... Straight section / 500... Add-on guide rib (sliding member) / 500a... Third outer edge section (sliding part) / 600... Cushioning member (elastic member, damping member) / 700... Second rib / G1... First guide / G1B... Guide section / G1BR... Rib (guide rib) / G1C... Guide section / G1Ca... Opening / JN... Branch section / P1... First position / P2... Second position / R1... First transport path / R2... Second transport path / S... Sheet

Claims

1. A conveying unit for conveying a sheet; a first conveying path through which the sheet passes, having a first guide for guiding the sheet conveyed by the conveying unit; a second conveying path branching off from the first conveying path, through which the sheet conveyed by the conveying unit passes; a movable guide having first and second ribs spaced apart in a width direction perpendicular to the sheet conveying direction, and movable to a first position where the first and second ribs guide the sheet to the first conveying path, and a second position where the first and second ribs guide the sheet to the second conveying path; and an elastic member disposed on the first guide, which the first rib contacts and elastically deforms when the movable guide moves from the first position to the second position, wherein at least a portion of the sheet guide surface of the second rib is made of a sliding member that has higher sliding properties with respect to the sheet than the first rib, and when the movable guide moves from the first position to the second position, the first rib contacts the elastic member before the second rib contacts the first guide. Sheet conveying device.

2. The sheet conveying device according to claim 1, wherein the moving guide has a main body, the first rib is integrally formed with the main body, and the second rib has a mounting rib integrally formed with the main body at a position spaced apart from the first rib in the width direction, and the sliding member is mounted on the mounting rib.

3. The sheet conveying device according to claim 1 or 2, wherein the elastic member is a damping member that contacts the first rib and dampens the movement of the moving guide.

4. The sheet conveying device according to any one of claims 1 to 3, comprising a rotating body disposed on the first guide side of the first conveying path, wherein the second rib is disposed further outward in the width direction than the rotating body.

5. The sheet conveying device according to any one of claims 1 to 4, wherein the sheet guide surface of the second rib is configured such that the downstream portion in the sheet conveying direction is curved on the first surface facing the first guide, and the sliding member is not provided on the upstream portion in the sheet conveying direction on the first surface, but is provided on the downstream portion in the sheet conveying direction.

6. The sheet conveying device according to any one of claims 1 to 5, wherein the first guide is arranged such that it partially overlaps with the first rib of the moving guide in the second position when viewed from the width direction, and has a plurality of guide ribs on their outer edges that can guide a sheet into the first conveying path when the moving guide is in the first position, and the elastic member is arranged between the plurality of guide ribs in the width direction.

7. The sheet conveying device according to claim 4, wherein the rotating body is configured to rotatably protrude from an opening formed in the first guide and contact the sheet.

8. The sheet conveying device according to claim 4 or 7, wherein the first guide is arranged such that it partially overlaps with the first rib of the moving guide in the second position when viewed from the width direction, and has a plurality of guide ribs on their outer edges that can guide a sheet into the first conveying path when the moving guide is in the first position, and the rotating body is arranged downstream of the guide rib in the sheet conveying direction.

9. The sheet conveying device according to claim 4, 7, or 8, wherein the second rib is not positioned opposite the rotating body when viewed from the width direction.

10. The sheet conveying device according to claim 1, comprising a rotating body disposed on the first guide side of the first conveying path, wherein the second rib is a rib disposed closer to the rotating body than the first rib in the width direction.

11. The sheet conveying device according to any one of claims 1 to 10, wherein the conveying unit has a plurality of contact rotating parts that are spaced apart in the width direction and come into contact with the sheet, and a support shaft that supports the contact rotating parts, and has an upstream roller that is positioned adjacent to the upstream of the moving guide in the sheet conveying direction, and the second rib is a rib that is positioned to overlap with the contact rotating parts in the width direction when viewed from the sheet conveying direction.

12. The sheet conveying device according to claim 2, wherein the upstream end of the sliding member in the sheet conveying direction is located further upstream in the sheet conveying direction than the upstream end of the rib to be mounted in the sheet conveying direction.

13. The sheet conveying device according to claim 12, wherein the surface of the first rib facing the first guide has an upstream portion and a downstream portion located downstream of the upstream portion in the sheet conveying direction, and the sliding member is positioned so as viewed from the width direction that it is located outside the upstream portion and not outside at least a portion of the downstream portion.

14. The sheet conveying device according to claim 12, wherein the surface of the first rib facing the first guide has an upstream portion and a downstream portion located downstream of the upstream portion in the sheet conveying direction, and the sliding member is positioned so as viewed from the width direction, to be outside the downstream portion and not to be outside at least a portion of the upstream portion.

15. The sheet conveying device according to any one of claims 1 to 14, wherein the surface of the first rib facing the first guide has a curved portion that is concave when viewed from the width direction and a straight portion that is straight, and the sliding member is positioned so as to be outside the curved portion when viewed from the width direction and is not positioned outside at least a part of the straight portion.

16. The sheet conveying device according to any one of claims 1 to 15, wherein each of the sliding members is attached to the moving guide from a direction different from the reverse flow direction from downstream to upstream in the sheet conveying direction.

17. A conveying unit for conveying a sheet; a first conveying path through which the sheet passes, having a first guide for guiding the sheet conveyed by the conveying unit; a branching path branching from the first conveying path, through which the sheet conveyed by the conveying unit passes; a movable guide having a plurality of ribs spaced apart in a width direction perpendicular to the sheet conveying direction, for guiding the sheet to the first conveying path or the second conveying path, and switchable between a first position for guiding the sheet to the first conveying path and a second position for guiding the sheet to the second conveying path; an elastic member that elastically deforms when the first rib among the plurality of ribs abuts against the movable guide as it moves from the first position to the second position; a sliding member attached to a rib different from the first rib among the plurality of ribs, for guiding the sheet, and having higher sliding properties against the sheet than the first rib; wherein, when the movable guide moves from the first position to the second position, the first rib abuts against the elastic member before the sliding member abuts against the first guide. Sheet conveying device.

18. The sheet conveying device according to claim 17, wherein the sliding member is attached to the moving guide such that at least a portion of the sliding member is located outside the outer edge of the rib to which the sliding member is attached, and the elastic member is arranged to abut against the ribs among the plurality of ribs to which the sliding member is not attached.

19. A sheet conveying device according to claim 14, comprising a rotating body that is rotatable in contact with a sheet, wherein the sliding member overlaps with the rotating body when viewed from a width direction perpendicular to the sheet conveying direction, and the rotating body is arranged adjacent to the sliding member in the width direction.

20. An image forming apparatus comprising a sheet transport device according to any one of claims 1 to 19, and an image forming unit for forming an image on a sheet.

Images