JP2019112197A - Sheet conveying device, image reading device, and image forming device - Google Patents

Abstract

To provide a sheet conveying device capable of retracting a flag member for detecting a sheet when an opening/closing member moves rotationally.SOLUTION: A sheet conveying device has: an opening/closing member which is rotationally movable between a closed position and an open position with respect to a sheet supporting part; a flag member which is disposed so as to be rotationally movable on the opening/closing member and detects a sheet on the sheet supporting part; and an assist member which is disposed on the opening/closing member, and is located at a first position when the opening/closing member is located at the closed position, and can displace from the first position to a second position by self-weight when the opening/closing member is located at the open position. The assist member does not act on the flag member when the assist member is located at the first position, and presses the flag member to urge the flag member toward the opening/closing member when the assist member is located at the second position.SELECTED DRAWING: Figure 9

Description

  The present invention relates to a sheet conveying apparatus having a detection member that detects the presence or absence of a sheet in a sheet conveyance path, an image reading apparatus including the same, and an image forming apparatus.

  An image forming apparatus for producing a recording sheet using an electrophotographic method, such as an electrophotographic copying machine, comprises an image reading apparatus having an image reading unit and an image forming apparatus for forming a toner image on an image carrier such as a photosensitive drum. And a sheet conveying device for conveying a sheet from a feeding tray or the like.

  Such a sheet conveying apparatus is provided with a mechanism for detecting whether or not sheets are stacked on the sheet stacking tray. As the sheet detection mechanism, for example, a detection flag that can be rotated by its own weight is provided in the sheet conveyance path, and when the sheet is set on the sheet stacking tray, the sheet detection flag is pressed by the leading end of the sheet and rotated to shield the photo interrupter Recognize the presence of the sheet by releasing. On the contrary, when there is no sheet, the sheet detection flag shields the photo interrupter to recognize that the sheet is absent. Thus, it is possible to determine the presence or absence of the sheet.

  Further, the sheet conveying apparatus as described above enables the sheet conveying path to be opened so that the sheet can be removed when the sheet is jammed during conveyance. Therefore, the sheet conveyance path is configured by the apparatus body and the openable and closable member that can be pivoted to this, and when the sheet is clogged, the clogged member can be removed by pivoting the open and close member to open the transport path. And

  In the above configuration, when the opening and closing member is rotated to open the sheet conveying path, the sheet detection flag is rotated by its own weight and retreats so as to abut on the surface of the opening and closing member. However, since the opening / closing member may collide with peripheral objects such as the wall surface of the installation location if the rotation angle is too open, the rotation angle is limited to a predetermined range. In such a case, even if the sheet conveying path is completely opened by rotating the opening and closing member, the sheet detection flag can not be retracted to the surface of the opening and closing member and remains protruded from the surface of the opening and closing member is there. If, in such a state, the member in the vicinity of the sheet detection flag is replaced, the sheet detection flag may be damaged.

  In order to solve the above problems, for example, in Patent Document 1, when the sheet detection flag is provided with a weight portion that generates a rotational moment about a rotation axis, and the opening and closing member is rotated to open the sheet conveyance path. A configuration has been proposed in which a rotational moment is generated so that the sheet detection flag abuts on the surface of the opening and closing member by the weight portion, and the sheet detection flag is retracted on the surface of the opening and closing member.

Unexamined-Japanese-Patent No. 2010-64851

  However, as in Patent Document 1, when the weight is provided to the sheet detection flag, it is necessary to adjust the inclination angle of the flag from the relationship of the rotational moment generated in the flag, and the angle between the sheet detection flag and the sheet stacking tray is small. Can be In such a case, the reaction force due to the weight of the sheet detection flag is increased, and when the thin sheet is set, the sheet may be easily buckled.

  Also, the following method may be considered as another method for preventing the sheet detection flag from protruding from the surface of the opening / closing member at the time of work such as maintenance. The sheet detection flag is provided such that the rotation center of the sheet detection flag is located above the opening and closing member when the opening and closing member is closed. With this configuration, when the opening and closing member is rotated to open the conveyance path, the sheet detection flag is easily hidden by the opening and closing member.

  However, when the rotation center of the sheet detection flag is positioned above the opening and closing member, the distance to the sheet stacking tray becomes long, so the sheet detection flag needs to be long. In particular, when the feed tray has a lift-up configuration, it is necessary to make the sheet detection flag longer. When the turning radius of the sheet detection flag becomes long, it is necessary to provide a notch in the guide member such as the opening and closing member in order to avoid the locus of turning of the flag, which causes a reduction in strength.

  The present invention solves the above-described problems, and an object thereof is to retract a flag member for detecting a sheet when the opening and closing member is rotated without causing any trouble in sheet conveyance. A sheet conveying apparatus, an image reading apparatus including the sheet conveying apparatus, and an image forming apparatus.

  A representative configuration according to the present invention for achieving the above object is a sheet conveying device for conveying a sheet supported by a sheet support, wherein the sheet is rotated between a closed position and an open position with respect to the sheet support. A movable opening / closing member, a flag member rotatably provided on the opening / closing member, for detecting a sheet on the sheet support, and the opening / closing member provided in the closed position And an assist member displaceable from the first position to a second position by its own weight when the open / close member is in the open position. When in the first position, it does not act on the flag member, and when in the second position, the flag member is pressed to bias the flag member toward the opening / closing member. I assume.

  According to the present invention, it is possible to bias the flag member for detecting the sheet when the opening and closing member is pivoted to the open position toward the opening and closing member.

A diagram schematically showing an entire configuration of an image reading apparatus provided with a sheet conveying apparatus A diagram schematically showing the configuration of a document tray and a conveyance unit of a sheet conveyance apparatus Top view of the feeding unit and separating unit of the sheet conveying apparatus A perspective view of the vicinity of a document set detection sensor of a sheet conveying apparatus Sectional view in the vicinity of the assist member of the document set detection sensor of the sheet conveying apparatus A perspective view of the abutting portion of the flag member and the assist abutting portion of the assist member when the opening and closing guide of the sheet conveying apparatus is closed A schematic view showing a movement until a document is set and fed to a document tray of a sheet conveying apparatus A schematic view showing the sheet conveying apparatus with the open / close guide open A schematic view showing positions of a flag member and an assist member in a state in which the opening and closing guide of the sheet conveying apparatus is closed and in a state in which the opening and closing guide is open. A perspective view showing the positional relationship between the transport unit and the flag member when the open / close guide of the sheet transport apparatus is open Schematic which shows the position of the flag member of the state which has opened and closed the opening-and-closing guide of the sheet conveying apparatus which concerns on 2nd Embodiment, and an open state Schematic which shows the position of the flag member of the state which has opened and closed the opening-and-closing guide of the sheet conveying apparatus which concerns on 3rd Embodiment, and an open state

First Embodiment
In the first embodiment, an image reading apparatus provided with a sheet conveying apparatus for conveying an original which is a sheet will be described as an example.

<Image reader>
FIG. 1 is a view schematically showing the entire configuration of the image reading apparatus. The image reading apparatus comprises an image reading unit 200 and a sheet conveying apparatus 80.

  The sheet conveying device 80 feeds the document S one by one onto the platen 18 made of transparent glass. Further, the sheet conveying device 80 is configured to be openable and closable with respect to the image reading unit 200, and acts to press the document placed on the platen 18.

  The image reading unit 200 optically reads an image of a document conveyed by the sheet conveyance device 80 or a document placed on the platen 18, photoelectrically converts the image, and inputs the image information. The image reading unit 200 has a contact image sensor 24 as a first reading unit that reads an image on one side of a moving document conveyed on the platen 18. The contact image sensor 24 is fixed at a predetermined position (the position shown in FIG. 1) on the sheet conveying apparatus 80 side, and reads an image on one side of an original conveyed on the platen 18.

  The image reading apparatus also has a second reading unit that reads an image on the other side of the document. The second reading means is constituted by a movable scanner unit 204 having a lamp 202, a mirror 203 and the like, mirrors 205 and 206, a lens 207, an image sensor 208 and the like. The second reading unit is provided on the image reading unit 200 side. The second reading unit stops the scanner unit 204 at a predetermined position (solid line position shown in FIG. 1) and reads an image of the other side of the document conveyed on the platen 18 on the scanner unit 204. The second reading unit reads the image on the other side of the document placed on the platen 18 while moving the scanner unit 204 along the platen 18.

<Sheet conveying device>
The sheet conveying device 80 has the document tray 11 at the upper side. The document tray 11 serves as a sheet support unit on which the document is placed, and the document S placed on the document tray 11 is sequentially fed by the feeding roller 1 from the uppermost document. The fed originals S are separated and fed one by one by the conveyance roller 3 and the separation roller 4. When the document S separated and fed passes over the platen 18 of the image reading unit 200, an image is read by one or both of the scanner unit 204 and the contact image sensor 24. The document S whose image has been read is discharged onto the discharge tray 19 by the discharge roller 16.

  FIG. 2 is a view schematically showing the configuration of the document tray 11 and the transport unit. A document width regulation plate 10 for regulating the width direction of the stacked documents S is provided on the document tray 11. Further, the document tray 11 is configured to be capable of moving up and down by drive means (not shown). The feed roller 1 is rotatable about a shaft 13, and is pivoted about the shaft 5 by an arm 2 so as to be able to move up and down with respect to the document S stacked on the document tray 11.

  The opening and closing guide 6 which is an opening and closing member is provided with a flag member 100 serving as an actuator of the document set detection sensor 102 for detecting the presence or absence of the document on the document tray 11. The document set detection sensor 102 uses a photo interrupter and detects that a sheet is set on the document tray 11 when the optical axis is blocked by the flag member 100 (hereinafter referred to as sensor ON). Conversely, when the optical axis is not blocked by the flag member 100 (hereinafter referred to as sensor OFF), it is detected that the document is not set on the document tray 11.

  The arm 2 is provided with an actuator 90 of a feed position detection sensor 91 that determines the raised position (feed position of the document) of the document tray 11. The feed position detection sensor 91 uses a photo interrupter, and when the sensor is in the ON state, the sheet can be fed. Conversely, when the sensor is in the OFF state, the document tray 11 needs to be raised by a driving unit (not shown).

  FIG. 3 shows a plan view of the feeding portion and the separating portion. Pulleys 8 and 9 are respectively provided on the feeding roller 1 and the conveying roller 3, and the timing belt 7 is stretched to transmit the driving of the motor M (see FIG. 2) to the feeding roller 1. The arm 2 is biased by a spring clutch 12, and when the motor M rotates in the forward direction, the arm 2 descends and contacts the upper surface of the document on the document tray 11. At the time of forward rotation of the motor, the feed roller 1 and the transport roller 3 rotate in the direction of feeding the document to feed the document. Further, when the motor M rotates in reverse, the spring clutch 12 locks and raises the arm 2.

(Document set detection mechanism)
Next, a document set detection mechanism provided in the sheet conveying apparatus will be described. FIG. 4 is a perspective view of the vicinity of the document set detection sensor.

  The document set detection sensor 102 is held by the open / close guide 6. The flag member 100 has two flag shaft portions 101 held with respect to the open / close guide 6. The flag shaft portion 101 is rotatably held at one end with respect to the bearing portion 103 of the opening / closing guide 6, and the other end is held rotatably and movably upward. The flag member 100 has an actuator unit 104, and when the document S is set, the actuator unit 104 is pressed by the front end of the document, and rotates around the flag shaft unit 101.

  The flag member 100 includes a detection unit 105. When the flag member 100 is rotated about the flag shaft unit 101, the detection unit 105 shields the document set detection sensor 102 from light to detect that the document S has been set. Also, the flag member 100 has a protrusion 107. When the open / close guide 6 is closed, the position of the center of gravity of the flag member 100 is designed such that a rotational moment in the clockwise direction (direction of arrow A) in FIG. As a result, the protrusion 107 comes into contact with the flag stopper 108 provided on the open / close guide 6 to determine the rotation direction attitude of the flag member 100.

  The flag member 100 has a cylindrical flag abutment portion 109. The flag abutting portion 109 is a portion pressed by the assist member 110 as described later. Further, the center of gravity of the flag member 100 is slightly away from the center of rotation of the flag shaft portion 101, that is, the flag member 100 by about 0.2 mm in the horizontal direction. Therefore, the moment generated in the flag member 100 is very small.

  Further, an assist member 110 is rotatably attached to the opening and closing guide 6 and is provided so as to be displaceable between a first position and a second position according to the opening and closing operation of the opening and closing guide 6. The assist member 110 has two assist shaft portions 111 held with respect to the open / close guide 6. The assist shaft portion 111 is rotatably held by the bearing portion 112 of the open / close guide 6. The assist member 110 has a cylindrical assist abutment portion 113. The assist abutment portion 113 has a function of pressing the flag abutment portion 109 when the open / close guide 6 is opened as described later.

  Two weights 114 are attached to the assist member 110. The weight 114 of the present embodiment is a SUM material having a diameter of 6 mm and a length of 12 mm. The two weights 114 are disposed on both sides of the assist shaft 111, and are mounted such that the rotational moments of the assist member 110 by the weights 114 are in opposite directions with respect to the assist shaft 111. ing.

  FIG. 5 shows a cross-sectional view in the vicinity of the assist member 110 of the document set detection sensor 102. When the open / close guide 6 is closed, the assist member 110 is designed to have a center of gravity so that a moment in the counterclockwise direction (direction of arrow B) is generated with respect to the assist shaft 111 in FIG. When the assist projection 115 provided on the front and rear ends abuts on the stopper 116 provided on the open / close guide 6, the posture in the rotational direction of the assist member 110 is determined. At this time, the assist member 110 is at the first position, and the center of gravity is at a position slightly separated from the rotation center of the assist shaft 111 by about 0.2 mm in the horizontal direction, and occurs with respect to the assist shaft 111 The moment is very slight.

  FIG. 6 shows a perspective view of the flag abutment portion 109 of the flag member 100 and the assist abutment portion 113 of the assist member 110 when the open / close guide 6 is closed.

  The flag abutting portion 109 is provided at a position separated from the rotation center axis of the flag shaft portion 101. The flag abutting portion 109 is a cylindrical shape having a diameter of 3 mm, and is provided in parallel with the flag shaft portion 101. The assist abutment portion 113 is provided at a position away from the central axis of the assist shaft portion 111. The assist abutment portion 113 has a cylindrical shape with a diameter of 8 mm, and is provided in parallel with the assist shaft portion 111.

  When the open / close guide 6 is closed, the flag abutment portion 109 and the assist abutment portion 113 are separated by maintaining a fixed clearance without contacting each other. In this state, the assist member 110 does not act on the flag member 100. Along with the operation of opening the opening / closing guide 6, the relative positional relationship between the flag shaft portion 101 and the assist shaft portion 111 changes as described later. As a result, the flag abutment portion 109 and the assist abutment portion 113 abut on each other.

  FIG. 7 is a schematic view showing the movement until the document is set and fed to the document tray 11.

  The flag member 100 before the document S is set is held at an inclination of about 83 ° with respect to the placement surface of the document tray 11 (FIG. 7A). When the document S is set by the user, the flag member 100 starts to rotate clockwise around the flag shaft portion 101 by pressing the actuator portion 104 by the document S.

  When the flag member 100 is rotated by about 25 °, the document S dives under the flag member 100 (FIG. 7B). At this time, the detection unit 105 shields the document set detection sensor 102 to detect that the document S has been set. When the angle of the flag member 100 with respect to the setting direction of the document S is made as close as possible to 90 degrees, the document can be easily detected without buckling even a thin document such as a thin document.

  Then, when the document S is detected, the document tray 11 is lifted and lowered by a document tray lifting motor (not shown) and moved to a predetermined position (FIG. 7C). Thereafter, the feeding operation is performed by the feeding roller 1. After the predetermined number of sheets have been fed, the document tray 11 is raised and lowered by the document tray lifting motor (not shown) to move to the initial position, and the flag member 100 is also returned to the initial position, and the operation is completed. Note that the flag member 100 and the assist member 110 do not abut each other during this series of operations. The reason is that in the case of sheet detection, the flag abutment portion 109 is pivoted in a direction of retracting from the assist abutment portion 113 in order to pivot the flag member 100 clockwise in FIG. 7.

  Further, in the present embodiment, as shown in FIG. 7, the flag shaft portion 101 serving as the rotation center of the flag member 100 is positioned below the opening / closing guide 6 in the vertical direction with the opening / closing guide 6 closed. It is arranged as. Thus, even if the angle of the flag member 100 with respect to the setting direction of the document is made as close as possible to 90 degrees, it is not necessary to make the flag member 100 longer.

(Operation of flag member when opening and closing guide)
Next, the operation of the flag member 100 when the opening and closing guide 6 is opened will be described. For example, when a paper jam occurs in the reading apparatus or when parts are replaced at the time of maintenance, the open / close guide 6 is opened upward to perform work. FIG. 8 is a schematic view showing the open / close guide 6 in an open state. The opening and closing guide 6 is rotatably held with respect to the reading device main body around a rotation shaft 117. When the user rotates the opening and closing guide 6 to open it, the document conveyance path is released. At this time, the opening angle requires a certain amount of space from the viewpoint of workability, but if the rotation angle is made too large, the open / close guide 6 may collide with peripheral objects such as the wall surface of the installation place. For this reason, the opening angle of the opening and closing guide 6 is set to a range in which work can be performed and an angle that avoids collision with surrounding objects. Then, the open / close guide 6 is held in a self-supporting state so as to facilitate work.

  With the opening operation of the opening and closing guide 6, the assist member 110 acts on the flag member 100, and when the opening and closing guide 6 is in the open position, the assist member 110 presses the flag member 100 to open and close the flag member 100. It acts to bias the side of the guide 6. Here, the action of the assist member 110 on the flag member 100 when the opening and closing guide 6 is opened and closed will be described in detail.

  FIG. 9 is a schematic view showing the positions of the flag member 100 and the assist member 110 in the open and closed states of the opening and closing guide 6. FIG. 9 (a) shows the open / close guide 6 in the closed position, and FIG. 9 (b) shows the open / close guide 6 in the open position.

  In the state where the opening and closing guide 6 is closed, as described above, the flag member 100 and the assist member 110 are held without contact in a state in which a slight counterclockwise moment (direction of arrow C) is generated by their own weight. It is done.

  When the opening and closing guide 6 is opened, the position of the assist shaft 111 moves relative to the flag shaft 101 in the counterclockwise direction, and the position of the assist shaft 111 in the vertical direction becomes the position of the flag shaft 101 It will be almost the same. On the other hand, the flag member 100 and the assist member 110 try to hold the posture determined by the position of the center of gravity. Therefore, the assist member rotates clockwise due to gravity, and the assist abutment portion 113 abuts on the flag abutment portion 109 to generate a force in the direction (arrow D direction) perpendicular to the tangent line. As a result, the flag member 100 generates a moment in the clockwise direction (direction of arrow E) with respect to the flag shaft portion 101, and rotates against the moment in the counterclockwise direction (direction of arrow F) by its own weight.

  The rotation is performed until the assist member 110 abuts against an assist stopper portion 118 provided on the top surface of the open / close guide 6. At this time, the assist member 110 is in the second position, and as shown in FIG. 9B, the flag member 100 is completely retracted in the guide surface of the open / close guide 6. Furthermore, even if the open / close guide 6 is opened, the assist abutment portion 113 is restricted in rotation by the assist stopper portion 118, so the flag abutment portion 109 is not pushed further. Then, the opening / closing guide 6 is completely opened and the operation of opening is ended by becoming independent. When closing the open / close guide 6, the original state is restored in the reverse procedure of opening.

  In addition, since both the flag abutment part 109 and the assist abutment part 113 of the flag member 100 are arc-shaped, the contact point rotates while gradually moving in a state where the open / close guide 6 is opened. It will be.

  As described above, when the open / close guide 6 is opened, the flag member 100 is pressed by the assist member 110 and moved, whereby the flag member 100 is completely retracted in the guide surface of the open / close guide 6. Therefore, it is possible to reduce the risk of damage to parts when the operator contacts the flag member 100 with hands, parts or the like at the time of jam processing or maintenance.

  The effect of replacing the conveyance unit 121 for conveying a sheet will be described as a specific example. FIG. 10 is a perspective view showing the positional relationship between the transport unit 121 and the flag member 100 when the open / close guide 6 is open.

  In the state where the opening and closing guide 6 is opened, the flag member 100 is retracted into the surface of the opening and closing guide 6 as described above. In the embodiment of FIG. 10, the accommodation portion for accommodating the flag member 100 in the opening and closing guide 6 is formed by the groove portion 119 and the protection rib 120. Then, when the open / close guide 6 is opened, the flag member 100 is pressed by the assist member 110, retreats into the groove 119 provided in the open / close guide 6, and the periphery is protected by the protective rib 120.

  The conveying unit 121 is a unit having a feeding roller 1 which is a conveying member, an arm 2 and a conveying roller 3 and is a unit requiring maintenance when it is used for a long time. Therefore, it is detachably attached to the opening and closing guide 6. Then, at the time of maintenance, the open / close guide 6 is opened, and the transport unit 121 is pulled out in the direction substantially perpendicular to the sheet of the drawing to replace the rollers. If the flag member 100 protrudes from the guide surface when the transport unit 121 is pulled out, the flag member 100 may collide and damage the flag member 100 or the like. However, in the configuration of the embodiment described above, since the flag member 100 is retracted in the guide surface of the open / close guide 6, the risk can be reduced. Therefore, in the present embodiment, the flag member 100 is disposed in the vicinity of the transport unit 121 to miniaturize the apparatus.

  Further, by retracting the flag member 100 into the guide surface of the opening / closing guide 6 by the assist member 110, the flag shaft portion 101 serving as the rotation center of the flag member 100 is at the lower position in the vertical direction when the opening / closing guide 6 is closed. By arranging, the length of the flag member 100 can be shortened.

  In addition, although the conveyance unit 121 was mentioned as an example in this embodiment, also when replacement parts, such as another conveyance roller and a sensor, exist in the vicinity of the flag member 100, it is effective. In addition, it is effective not only at the time of maintenance but also when there is an operation to open the open / close guide 6 such as jam processing.

  Further, although the flag member 100 is completely retracted to the inside from the guide surface of the open / close guide 6 in the present embodiment, a certain effect can be obtained even in a state in which the flag member 100 is not completely retracted.

  Further, in the present embodiment, an example in which the document tray 11 has a lift-up configuration has been described, but the same effect can be obtained with a fixed tray without the lift-up configuration.

  Further, in the present embodiment, the weight 114 is held by the assist member 110, but even if the weight does not exist, certain effects can be obtained.

  Although the sheet conveying apparatus having the flag member 100 and the assist member 110 is used for the image reading apparatus in the present embodiment, the sheet conveying apparatus may be used for an image forming apparatus having an image forming unit for forming an image on a sheet. It is possible.

Second Embodiment
In the embodiment described above, when the opening and closing guide 6 is opened, the assist member 110 and the flag member 100 rotate in the same direction and the assist member 110 presses the flag member 100, but the assist member is as follows. The flag member 100 may be retracted by rotating the flag member 110 in the opposite direction.

  FIG. 11 is a schematic view showing the positions of the flag member 100 and the assist member 110 in the state in which the open / close guide 6 is in the closed position and in the open position in the second embodiment. FIG. 11 (a) shows the open / close guide 6 in a closed state, and FIG. 11 (b) shows the open state.

  When the open / close guide 6 is closed, the flag member 100 is held by a stopper (not shown) in a state in which a slight counterclockwise (direction of arrow C) moment is generated by its own weight. On the other hand, the assist member 110 is held by the second stopper portion 122 in a state in which a moment in the clockwise direction (arrow G direction) is generated by its own weight. The flag member 100 and the assist member 110 are held without being in contact with each other.

  As the open / close guide 6 is opened, the relative position of the assist shaft 111 to the center of gravity of the assist member 110 changes in the vertical direction. Then, when the open / close guide 6 opens to a predetermined angle, the rotational moment due to the gravity center position of the assist member 110 switches from the clockwise direction (arrow G direction) to the counterclockwise direction (arrow H direction).

  For this reason, the assist abutment portion 113 abuts on the flag abutment portion 109, and generates a force in the direction (arrow I direction) perpendicular to each tangent line. As a result, the flag member 100 generates a moment in the clockwise direction (direction of arrow E) with respect to the flag shaft portion 101, and rotates against the moment in the counterclockwise direction (direction of arrow F) by its own weight. The rotation is performed until the assist member 110 abuts against the assist stopper portion 118. At this time, the flag member 100 is completely retracted in the guide surface of the open / close guide 6.

  As described above, similarly to the first embodiment, when the opening and closing guide 6 is opened, the flag member 100 is completely retracted in the guide surface of the opening and closing guide 6 by pressing and moving the assist member 110. As a result, the risk of damage to parts can be reduced by the operator contacting the flag member 100 with hands, parts, etc. at the time of jam processing or maintenance.

Third Embodiment
In the embodiment described above, an example has been shown in which the direction of the rotational moment due to the weight of the assist member 110 is switched while moving from the position where the open / close guide 6 is closed to the open position. However, when the opening and closing guide 6 is opened, the direction of the rotational moment by the weight of the assist member 110 may be the same.

  FIG. 12 is an operation explanatory view of the flag member 100 and the assist member 110 provided in the opening and closing guide 6 in the third embodiment. 12 (a) shows the open / close guide 6 in the closed position, and FIG. 12 (b) shows the open / close guide 6 in the open position.

  As shown in FIG. 12, the flag member 100 is pivotable about the flag shaft portion 101, and the assist member 110 is pivotable about the assist shaft portion 111. When the open / close guide 6 is in the closed position, the assist abutment portion 113 of the assist member 110 suspended by its own weight is at a position not acting on the flag abutment portion 109 of the flag member 100.

  When the open / close guide 6 moves from the closed position of FIG. 9A to the open position of FIG. 9B, both the assist member 110 and the flag member 100 rotate clockwise, and the assist abutment portion 113 Pushes the flag abutting portion 109 to retract the flag member 100 into the guide surface of the open / close guide 6. By this, the same effect as the embodiment described above can be obtained.

6 ... opening / closing guide 11 ... document tray 91 ... feeding position detection sensor 100 ... flag member 101 ... flag shaft section 102 ... document set detection sensor 103 ... bearing section 109 ... flag abutting section 110 ... assist member 111 ... assist shaft section 112 ... bearing portion 113 ... assist abutment portion 114 ... weight 117 ... rotational shaft 118 ... assist stopper portion 119 ... groove portion 120 ... protection rib 122 ... second stopper portion

Claims (8)

A sheet conveying apparatus for conveying a sheet supported by a sheet support unit,
An opening / closing member that can be pivoted to a closed position and an open position with respect to the seat support;
A flag member provided rotatably on the opening and closing member for detecting a sheet on the sheet support portion;
Provided on the opening and closing member, the opening and closing member is in the first position when the opening and closing member is in the closed position, and when the opening and closing member is in the open position, the second position from the first position by its own weight An assist member displaceable to
Have
The assist member does not act on the flag member when in the first position, and presses the flag member when in the second position to urge the flag member toward the open / close member. Sheet conveying apparatus characterized in that.   The assist member is rotatably provided on the opening and closing member, and is separated from the flag member when in the first position, and the opening and closing member moves from the closed position to the open position. The seat according to claim 1, wherein the seat is pivoted from the first position to the second position by its own weight, and the flag member is pressed to urge the flag member toward the opening / closing member. Transport device.   3. The sheet conveying apparatus according to claim 1, wherein a rotation center of the flag member is disposed below the opening / closing member when the opening / closing member is in a closed position.   The direction of the rotational moment of the assist member due to its own weight is switched during the movement of the open / close member from the closed position to the open position, according to any one of claims 1 to 3. Sheet conveying device.   The sheet conveying device according to any one of claims 1 to 4, wherein the opening and closing member has a storage portion for storing the flag member.   The conveyance unit having a conveyance member for conveying a sheet, wherein the conveyance unit detachable from the opening / closing member is disposed in the vicinity of the flag member. A sheet conveying apparatus according to any one of the preceding claims. In an image reading apparatus that conveys a sheet and reads an image,
A sheet conveying apparatus according to any one of claims 1 to 6.
A reading unit that reads an image formed on a sheet;
An image reading apparatus having: In an image forming apparatus for forming an image on a sheet,
A sheet conveying apparatus according to any one of claims 1 to 6.
An image forming unit that forms an image on a sheet;
An image forming apparatus comprising:

Images