JP2022043632A - Sheet conveying device and image forming device - Google Patents

Abstract

To provide an image forming device capable of suppressing breakage of a projection for restricting an axial movement of a rotating member when a load is applied to the projection.SOLUTION: An image forming device 100 comprises a full-loading detection flag 202 which is rotated by the contact of a sheet and a full-loading detection sensor 165 which detects the rotation of the full-loading detection flag 202. The full-loading detection flag 202 has a first projection 202d which restricts the full-loading detection flag 202 from moving in the axial direction by abutting a third support part 174. A rib 202d2 is disposed on a surface 202d3 of the first projection 202d opposite to a first contact surface 202d1.SELECTED DRAWING: Figure 3

Description

The present invention relates to a sheet transporting device for transporting sheets and an image forming apparatus including the same.

Conventionally, a sheet transport device that transports a sheet to an image forming unit such as a copying machine or a printer has a rotating member that rotates about a rotation axis when pushed by the sheet, and by detecting the rotation of the rotating member. Those that detect the passage of sheets and the loading of sheets loaded on the discharge tray are known.

In the rotating member used in this type of sheet transport device, the protruding portion protruding from the outer peripheral surface of the rotating shaft abuts on the regulating portion provided separately from the rotating member, so that the axial direction (thrust direction) of the rotating shaft is reached. There is something that regulates the movement to (Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-81717

With respect to such a rotating member, the user may accidentally touch the rotating member, and the protruding portion of the rotating member is pressed against the regulating portion, so that a load is applied to the protruding portion and the protruding portion may be damaged.

An object of the present invention is to prevent the protruding portion from being damaged when a load is applied to the protruding portion for restricting the axial movement of the rotating member.

One aspect of the present invention includes a transporting means for transporting a sheet, a rotating member having a rotating shaft and rotating when the sheet comes into contact with the sheet, a detecting means for detecting the rotation of the rotating member, and the rotating member as a shaft. A plate protruding from the outer peripheral surface of the rotating shaft, comprising a restricting portion that restricts movement in a direction, wherein the rotating member has a contact portion that contacts the sheet and a first surface that contacts the restricting portion. It is a sheet transport device having a shape-like protruding portion, and the protruding portion has a rib on a second surface which is a surface opposite to the first surface.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide a sheet transport device capable of suppressing damage to a protruding portion when a load is applied to the protruding portion for restricting the axial movement of the rotating member.

The schematic diagram of the image forming apparatus which concerns on this embodiment. Perspective view of the sheet ejection part. Enlarged view showing the protruding part of the full load detection flag. Top view showing the protrusion of the full load detection flag. A perspective view of the full load detection flag. Enlarged view showing the support part of the full load detection flag. A perspective view showing a state in which the full load detection flag is bent.

Hereinafter, the image forming apparatus including the sheet conveying apparatus according to the present embodiment will be described with reference to the drawings. The dimensions, materials, shapes, relative arrangements, etc. of the components described in the following embodiments are not intended to limit the scope of application of this technology to those unless otherwise specified. do not have.

<About the schematic configuration of the image forming device>
The schematic configuration of the image forming apparatus 100 according to this embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view of an intermediate transfer tandem image forming apparatus 100 in which image forming portions 140 of four colors using an electrophotographic method are arranged side by side on an intermediate transfer belt 145.

The image forming apparatus 100 has a sheet storage unit 109 in which the sheet S as a recording medium is stored. The sheet S stored in the sheet storage unit 109 is fed by the feeding roller pair 110 in accordance with the image forming timing of the image forming apparatus 100. The sheet S fed by the feed roller pair 110 passes through the transport path and is transported to the resist roller pair 120. Then, after the skew correction and timing correction of the sheet S are performed by the resist roller pair 120, the sheet S is sent to the secondary transfer unit 130. The secondary transfer unit 130 is composed of a secondary transfer inner roller 131 and a secondary transfer outer roller 132 that are substantially opposed to each other, and transfers a toner image to the sheet S by applying a predetermined pressing force and an electrostatic load bias. Let me.

The image forming unit 140 as an image forming means includes a photoconductor 141, an exposure device 142, a developing device 143, and a primary transfer device 144. The photoconductor 141 whose surface is uniformly charged by a charging means (not shown) is irradiated with light based on the image information printed by the exposure apparatus 142. As a result, the surface of the photoconductor 141 is exposed, and an electrostatic latent image is formed on the surface of the photoconductor 141. Toner development is performed on the electrostatic latent image formed on the photoconductor 141 in this way by the developer 143, and the toner image is formed on the photoconductor 141. After that, a predetermined pressing force and an electrostatic load bias are applied by the primary transfer device 144, and the toner image is transferred onto the intermediate transfer belt 145. In the present embodiment, the image forming apparatus 100 includes four sets of the image forming unit 140 described above, yellow Y, magenta M, cyan C, and black Bk.

Next, the intermediate transfer belt 145 will be described. The intermediate transfer belt 145 is conveyed and driven in the direction of arrow A in FIG. The image forming process by the image forming unit 140 of each color described above is performed at the timing of superimposing on the upstream toner image primaryly transferred on the intermediate transfer belt 145. As a result, a full-color toner image is finally formed on the intermediate transfer belt 145 and transferred to the secondary transfer unit 130.

In the secondary transfer unit 130, a full-color toner image is secondarily transferred from the intermediate transfer belt 145 onto the sheet S conveyed from the sheet storage unit 109. After that, the sheet S is conveyed to the fuser 150. The fuser 150 has a heat source unit 151 and a pressurizing unit 152. The fuser 150 melts and fixes the toner on the sheet S by a predetermined pressing force by the heat source unit 151 and the pressurizing unit 152 which are substantially opposed to each other and heating by the heat source unit 151. The heat source portion 151 for heating the sheet S is arranged on the same side as the image forming surface of the sheet S, and the pressurizing portion 152 for applying pressure to the sheet S is arranged on the opposite side thereof.

In the case of single-sided printing, the sheet S on which the image is fixed by the fixing device 150 is discharged onto the discharging tray 170 as the loading portion by the discharging roller 161 as the conveying means. In the case of double-sided printing, the sheet S on which the image is fixed on one side is branched by the first switching flapper 153 and conveyed toward the reversing roller 162.

Here, the sheet S transported to the reversing roller 162 is transported to the double-sided transport path 180 by the reversing operation of the reversing roller 162 after the rear end of the sheet S has passed the second switching flapper 154. The sheet S that temporarily jumps out of the machine during this reversing operation is supported by the reversing guide 171. The sheet S transported to the double-sided transport path 180 is again subjected to skew correction and timing correction by the resist roller pair 120, and then sent to the secondary transfer unit 130 to transfer the image on the second surface and transfer the image. Is fixed by the fuser 150. Then, the sheet S is discharged onto the discharge tray 170 by the discharge roller 161 to complete double-sided printing. Since the discharge tray 170 for loading the discharged sheet S has an ascending slope from the upstream to the downstream in the discharge direction of the sheet S, the discharged sheet S is moved to the upstream side in the discharge direction by the weight of the sheet S itself. To be consistent.

The image forming apparatus 100 has a control unit 190, and the control unit 190 controls the above-mentioned sheet transfer and image formation. Further, the signal of the full load detection sensor 165, which will be described later, is sent to the control unit 190.

<Structure of full load detection flag>
Next, the configuration of the full load detection flag will be described with reference to FIGS. 2 to 7. FIG. 2 is a perspective view of the sheet discharging portion B shown in FIG. In the present embodiment, the full load means that the height of the sheet S loaded on the discharge tray 170 is equal to or higher than the predetermined height h. When the discharge tray 170 is full of the sheet S, the sheet S may fall from the discharge tray 170 or jam may occur.

As shown in FIG. 2, the sheet discharging unit B is provided with a full load detection flag 202, which is a rotating member, and a full load detection sensor (photo interrupter) 165, which is a detection means for detecting the rotation of the full load detection flag 202. There is.

The full load detection flag 202 has a contact portion 202a that contacts the sheet S, a light shielding portion 202b that blocks the light of the full load detection sensor 165, and a rotation shaft 202c. The contact portion 202a contacts the uppermost sheet S among the sheets S loaded on the discharge tray 170. Both ends of the rotating shaft 202c are rotatably supported by the first support portion 172 and the second support portion 173 provided on the main body side of the image forming apparatus 100. Further, the rotary shaft 202c is positioned in the axial direction between the first support portion 172 and the second support portion 173 by a third support portion 174 as a regulation portion provided on the main body side of the image forming apparatus 100. In the present embodiment, the axial direction is the direction in which the rotation shaft 202c extends. When the contact portion 202a of the full load detection flag 202 is pushed by the sheet S, the rotation shaft 202c and the light-shielding portion 202b rotate integrally with the contact portion 202a. That is, as the number of sheets S loaded on the discharge tray 170 is large and the height of the sheets S is high, the contact portion 202a is pushed upward by the uppermost sheet S, and the full load detection sensor 202 is in a state of being greatly rotated. ..

When the sheet S loaded on the discharge tray 170 is not full (the height of the sheet S is less than h), the light-shielding portion 202b of the full-load detection flag 202 emits light from the light-emitting portion of the full-load detection sensor 165 to the light-receiving portion. It exists in a position to block it. On the other hand, when the sheet S loaded on the discharge tray 170 is full (the height of the sheet S is h or more), the contact portion 202a is pushed by the uppermost sheet S and the full load detection flag 202 is greatly rotated. It becomes a state. Then, as a result of the rotation of the light-shielding portion 202b of the full-load detection flag 202, the light-shielding portion 202b moves to a position where the light of the full-load detection sensor 165 is not blocked, and the full-load detection sensor 165 indicates that the full-load detection flag 202 is greatly rotated. Can be detected. Here, the control unit 190 can detect that the height of the seat S is h or more by the signal sent from the full load detection sensor 165.

FIG. 3 is an enlarged view of the vicinity of the first support portion 172, and FIG. 4 is a top view of the vicinity of the first support portion 172. Further, FIG. 5 is a perspective view showing only the full load detection flag 202. The full load detection flag 202 has a plate-shaped first protruding portion 202d and a second protruding portion 202e protruding outward from the outer peripheral surface of the rotating shaft 202c. The first projecting portion 202d is a flange-shaped projecting portion in which a part thereof greatly protrudes, and has a first contact surface 202d1 (first surface) perpendicular to the axial direction. Further, the first protruding portion 202d is provided with a rib 202d2 protruding from the surface 202d3 (second surface) opposite to the first contact surface 202d1. The rib 202d2 has a thin planar shape parallel to the axial direction of the rotation shaft 202c. In the present embodiment, the rib is a protrusion provided to reinforce the member.

The rib 202d2 is provided in the region including the root of the first protrusion 202d. Here, the root of the first protruding portion 202d is a portion of a boundary between the first protruding portion 202d and the rotation shaft 202c. In other words, the rib 202d2 protruding from the first protruding portion 202d is connected to the outer peripheral surface of the rotating shaft 202c.

The second protruding portion 202e is a protruding portion protruding from a part of the outer periphery of the rotating shaft 202c, and has a second contact surface 202e1 (first surface). Ribs 202e2 are provided on the surface 202e3 (second surface) of the second protrusion 202e opposite to the second contact surface 202e1.

The third support portion 174 provided on the main body side of the image forming apparatus 100 has a notch portion 174a as a recess. The rotation shaft 202c fits into the notch 174a of the third support portion 174. As shown in FIGS. 3 and 4, in a state where the rotating shaft 202c is fitted to the notch portion 174a, the first protruding portion 202d and the second protruding portion 202e are positioned to sandwich the third support portion 174 from both sides in the axial direction. Exists in. As a result, the first contact surface 202d1 of the first protrusion 202d and the second contact surface 202e1 of the second protrusion 202e come into contact with the third support portion 174, so that the full load detection flag 202 moves in the axial direction. Can be regulated.

As shown in FIG. 3, the first support portion 172 has a round hole (hole portion) 172a, and the end portion of the rotating shaft 202c on the light-shielding portion 202b side is inserted into the round hole 172a of the first support portion 172. To. FIG. 6 is an enlarged view of the vicinity of the second support portion 173. As shown in FIG. 6, the second support portion 173 has a round hole (hole portion) 173a, and the end portion of the rotating shaft 202c on the contact portion 202a side is inserted into the round hole 173a of the second support portion 173. .. That is, both ends of the rotating shaft 202c are rotatably supported by being inserted into two round holes 172a and 173a provided on the main body side of the image forming apparatus 100.

<How to install the full load detection flag>
Next, a method of attaching the full load detection flag 202 will be described. As described above, in the present embodiment, both ends of the rotating shaft 202c are supported by being inserted into two round holes 172a and 173a provided on the main body side of the image forming apparatus 100. Therefore, when the full load detection flag 202 is attached to the first support portion 172 and the second support portion 173, one end of the rotation shaft 202c is inserted into the round hole 172a, and then the other end while bending the rotation shaft 202c. Insert the portion into the round hole 173a.

In FIG. 4, the arrow C indicates the width of the notch 174a, and in FIG. 5, the arrow D indicates the width of the second protrusion 202e. In the present embodiment, the width C of the notch portion 174a is larger than the width D of the second protruding portion 202e. Therefore, the full load detection flag 202 is set to the first support portion 172 and the second support portion 173 by matching the phases of the second protrusion 202e and the notch portion 174a so that the second protrusion 202e passes through the notch 174a. It can be attached. This makes it possible to prevent the second protruding portion 202e from coming into contact with the third support portion when the full load detection flag 202 is attached to the main body side of the image forming apparatus 100, and to facilitate the attachment of the full load detection flag 202.

<About the deflection of the full load detection flag>
FIG. 7 is a diagram showing the displacement of the rotating shaft 202c in a state where the full load detection flag 202 is bent. As shown in FIG. 1, the full load detection flag 202 is provided on the upper part of the discharge tray 170. Therefore, when the user accidentally touches the contact portion 202a when taking out the sheet S loaded on the discharge tray 170, or when the user returns the sheet S taken out to the discharge tray 170, the sheet S touches the contact portion 202a. It may come into contact from the side. In such a case, a load is applied to the contact portion 202a in the direction of the arrow P, and the rotation shaft 202c is deformed into the shape shown by the broken line in FIG. 7. At this time, the first contact surface 202d1 of the first protrusion 202d is pressed against the third support portion 174, so that the first protrusion 202d is loaded in the direction opposite to the arrow P. However, in the present embodiment, since the rib 202d2 is provided on the surface 202d3 on the opposite side of the first contact surface 202d1 of the first protrusion 202d, even if the load is applied to the first protrusion 202d, the first protrusion 202d is the first. 1 It is possible to prevent the protruding portion 202d from being damaged.

The rib 202d2 shown in the present embodiment has a thin planar shape parallel to the axial direction of the rotating shaft 202c, but the shape of the rib 202d2 is not limited to the thin planar shape parallel to the axial direction of the rotating shaft 202c. For example, the rib 202d2 may be a protruding portion having an arc-shaped cross section. Further, the rib 202d2 may be a rib that is not parallel to the axial direction but extends at an angle with respect to the axial direction.

Further, although the rib 202d2 shown in the present embodiment is provided in the region including the root of the first protruding portion 202d, the rib 202d2 may be provided in the region not including the root of the first protruding portion 202d. However, since the rib 202d2 is provided in the region including the root of the first protruding portion 202d as shown in the present embodiment, it is possible to prevent the first protruding portion 202d from breaking from the root. Therefore, it is desirable that the rib 202d2 is provided in the region including the root of the first protrusion 202d.

Further, the first protruding portion 202d has a shape that greatly protrudes in the direction opposite to the bending direction shown in FIG. 7, and the first contact surface 202d1 is larger than the notched portion 174a of the third support portion 174. Therefore, even when the shape is deformed to the shape shown by the broken line in FIG. 7, it is possible to prevent the rotation shaft 202c from coming off from the third support portion 174. With the configuration that allows the rotating shaft 202c to be greatly bent in this way, it is possible to prevent the full load detection flag 202 from being damaged when a load is applied to the full load detection flag 202.

In the present embodiment, the full load detection flag 202 has two protrusions, a first protrusion 202d and a second protrusion 202e, and the first protrusion 202d and the second protrusion 202e provide the third support portion 174. The presence in the pinched position restricts the movement of the full load detection flag 202 in the axial direction. However, the rotating member may have one protruding portion, and the protruding portion may be configured to restrict movement of the rotating member in only one direction.

In the present embodiment, the protruding portion of the full load detection flag 202 has been illustrated, but the present invention can also be applied to, for example, a rotating member for detecting the passage of a sheet in the middle of a sheet transport path. Further, in the present embodiment, the electrophotographic image forming unit is exemplified as an example of the image forming unit that forms an image on the sheet, but the image forming unit may use the inkjet method.

100 Image forming device 165 Full load detection sensor 202 Full load detection flag 202a Contact part 202b Light-shielding part 202c Rotating shaft 202d First protrusion 202d1 First contact surface 202d2 Rib 202e Second protrusion 202e1 Second contact surface 202e2 Rib

Claims (10)

The means of transporting the sheet and
A rotating member that has a rotating shaft and rotates when the sheet comes into contact with it.
A detection means for detecting the rotation of the rotating member and
A regulatory unit that regulates the movement of the rotating member in the axial direction,
Equipped with
The rotating member is
The contact part that contacts the sheet and
A plate-shaped protruding portion protruding from the outer peripheral surface of the rotating shaft having a first surface that abuts on the regulating portion, and a plate-shaped protruding portion.
Have,
The sheet transfer device is characterized in that the protruding portion has a rib on a second surface which is a surface opposite to the first surface. The sheet transport device according to claim 1, wherein the rib has a planar shape parallel to the axial direction. The sheet transport device according to claim 1 or 2, wherein the rib is provided in a region including a root of the protrusion. The regulating portion has a recess and has a recess.
The sheet transfer device according to any one of claims 1 to 3, wherein the rotating shaft is fitted in the recess. The sheet transport device according to claim 4, wherein the first surface is larger than the recess. A hole into which the end of the rotating shaft is inserted is provided, and a support portion for rotatably supporting the rotating shaft is provided.
The sheet transport device according to any one of claims 1 to 5, wherein the sheet transport device is characterized by the above. The rotating member has another protruding portion protruding from the rotating shaft.
The sheet transport device according to any one of claims 1 to 6, wherein the protruding portion and the other protruding portion are provided at positions sandwiching the restricting portion from both sides in the axial direction. It has a loading section on which the sheet conveyed by the conveying means is loaded.
The sheet transport device according to any one of claims 1 to 7, wherein the rotating member is provided so that the contact portion comes into contact with a sheet loaded on the loading portion. The sheet transport device according to claim 8, wherein the detection means is a full load detection sensor for detecting full load of sheets in the loading section by detecting rotation of the rotating member. The sheet transport device according to any one of claims 1 to 9,
An image forming means for forming an image on a sheet,
An image forming apparatus characterized by having.

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