JP7133146B2 - Sheet holding device, sheet feeding device and image forming device - Google Patents

Description

The present invention relates to a sheet holding device, a sheet feeding device, and an image forming apparatus.

Conventionally, a regulating member that can move toward and away from an edge of a sheet, a rotating member that rotates according to the movement of the regulating member, and a member to be detected that is attached to the rotating member and rotates integrally. and a rotational position detecting means for detecting the rotational position of the member to be detected is known.

For example, Patent Document 1 discloses a document tray (sheet holding device) provided with a centering positioning mechanism that always aligns the center of the document in the width direction with the center of the document in the width direction of the fixed tray even if the size of the document changes. The centering positioning mechanism includes a pinion and a pair of racks provided on both sides of the pinion and engaged with the pinion to be guided in mutually passing directions (document width direction). Each of the rack pairs is provided with a width adjusting plate, and each width adjusting plate is movable in a direction toward and away from the widthwise end of the document. A gear attached to the input shaft of the rotary sensor is meshed with one of the rack pairs. When the user grabs one of the width adjusting plates and moves it, the rack pair moves, which causes the gear to rotate and move. The amount of rotation is detected by a rotary sensor. The detection result of this rotary sensor (the amount of rotation of the input shaft) is used to determine the size of the document in the width direction.

In the configuration disclosed in Patent Document 1, when a gear (rotating member) is attached to the input shaft (detected member) of the rotary sensor (rotational position detecting means), if a configuration that can cause play is adopted, the rotary sensor The rotation angle of the gear cannot be accurately detected from the detection result.

In order to solve the above-described problems, the present invention provides a regulating member that can move toward and away from an edge of a sheet, a rotating member that rotates according to the movement of the regulating member, and a A sheet holding device comprising: a member to be detected that is attached and integrally rotated; and rotational position detection means for detecting a rotational position of the member to be detected, wherein a contact portion of the rotating member contacts the member to be detected. The member to be detected rotates integrally with the rotating member by coming into contact with the contacted portion of the rotating member in the rotational direction of the rotating member, and one of the rotating member and the member to be detected and an engagement hole that engages with the rotating shaft provided on the other side, and one of the contact portion and the contacted portion is the D cut shaft of the D cut shaft. A cut surface and an engagement surface that is an inner wall surface of the engagement hole that engages with the D-cut surface, and a biasing force that maintains the contact state between the contact portion and the contacted portion. is applied between the rotating member and the member to be detected, and the biasing member has one end side of the D-cut surface in a direction orthogonal to the axial direction of the rotating shaft. It is characterized by being attached inside the engaging hole so as to be biased in a direction away from the mating surface .

According to the present invention, it is possible to accurately detect the rotation angle of the rotating member from the detection result of the rotation position detection means.

1 is a schematic diagram showing a copier according to an embodiment; FIG. 2 is an external perspective view showing a manual sheet feeding device of the copying machine; FIG. 1 is a perspective view of a manual feed tray according to an embodiment; FIG. FIG. 11 is a plan view showing a moving mechanism of side fences in the same manual feed tray; 4(a) to 4(c) are explanatory diagrams in the case where there is a discrepancy between the detection result of the rotary sensor and the rotation amount of the gear. It is an explanatory view showing the connection structure of the rotating shaft of the gear and the engagement hole of the rotor in the embodiment. FIG. 4 is a perspective view showing a state in which the rotating shaft of the gear is fitted in the engaging hole of the rotor of the rotary sensor and the spring is not yet attached; (a) is an explanatory diagram showing the shape of the spring before assembly, and (b) is an explanatory diagram showing the shape of the spring after assembly. FIG. 4 is a partially cross-sectional perspective view showing a state in which the rotating shaft of the gear is fitted into the engaging hole of the rotor of the rotary sensor and a spring is attached; The perspective view which shows the same gear alone. FIG. 11 is an enlarged view of a portion of the gear provided with a canopy portion that prevents the spring from leaving the space G; The perspective view which showed the gear shown in FIG. 11 with the partial cross section. (a) is a description of a case in which the length x of the D-cut surface and the length y of the notch in a cross section perpendicular to the axial direction of the rotation shaft of the gear are in a relationship to integrally rotate the rotor and the gear. figure. (b) is a relationship in which the length x of the D-cut surface and the length y of the notch in the cross section perpendicular to the axial direction of the rotation shaft of the gear prevent the rotor and gear from rotating integrally. Explanatory diagram of the case. FIG. 4 is a perspective view of a state in which the gear is removed from the rotary sensor; FIG. 4 is a perspective view of a state in which the rotary sensor is removed from the base of the manual feed tray; FIG. 2 is a plan view of a state in which the gear is removed from the rotary sensor; FIG. 4 is a perspective view showing a partial cross section of a rotary sensor to which a gear is attached and its surroundings; FIG. 4 is a cross-sectional view of the vicinity of the meshing portion between the gear and the rack; An explanatory view of the resistance E against the restoring force (elastic force) of the elastic deformation of the spring, which is received when the bent end portion is inserted into the space of the rotor and the spring comes into contact with the entrance edge of the space when the spring is attached. . (a) is an explanatory diagram showing the shape of a spring before assembly in Modification 1. FIG. (b) is an explanatory diagram showing the state of the spring during assembly. (c) is an explanatory diagram showing the shape of the spring after assembly. FIG. 11 is a perspective view showing a grip portion in Modification 2; FIG. 11 is a perspective view showing a state in which the connecting portion between the spring and the gripping portion is lifted and the winding direction of the wire constituting the gripping portion is reversely wound in Modified Example 2;

An embodiment in which a sheet holding device according to the present invention is applied to a manual feed tray of a copier as an image forming apparatus will be described below.
FIG. 1 is a schematic diagram showing a copier 1 according to this embodiment.
A copying machine 1 according to the present embodiment includes an image forming apparatus main body 2, an image reading device 3 arranged above the image forming apparatus main body 2, and a table-like feeder arranged below the image forming apparatus main body 2. A paper device 4 and an automatic document feeder 5 arranged above the image reading device 3 so as to be openable and closable are provided. The copying machine 1 also includes a switchback device 42 and a manual paper feeding device 70 .

The image forming apparatus main body 2 includes a drum-shaped photoreceptor 10 as an image carrier inside thereof. Around the photoreceptor 10, a charging device 11 is arranged on the left side in the figure, and along the rotation direction of the photoreceptor 10 (counterclockwise direction: arrow A in the figure), a developing device 12, a transfer device 13, and a cleaning device 14 are arranged. are placed. The transfer device 13 is configured by winding a transfer belt 17 between upper and lower rollers 15 and 16, and is configured to press the transfer belt 17 against the peripheral surface of the photoreceptor 10 at the transfer position T. As shown in FIG.

To the left of the charging device 11 and the cleaning device 14, a toner replenishing device 20 for replenishing new toner to the developing device 12 is arranged. Further, inside the image forming apparatus main body 2, a sheet conveying device D1 is arranged which feeds sheets such as paper and OHP sheets from a supply position described later and conveys them to a stack position via a transfer position T. The sheet conveying device D1 includes a supply path R1, a manual supply path R2, and a sheet conveying path R, which will be described later. The sheet conveying path R passes between the photoreceptor 10 and the transfer device 13, extends from bottom to top in the figure, and then curves to the left, forming a substantially L shape.

A registration roller 21 is arranged on the sheet conveying path R at a position upstream of the photosensitive member 10 in the sheet conveying direction. A fixing device 22 is arranged downstream of the photosensitive member 10 in the sheet conveying direction. The fixing device 22 includes a pair of fixing rollers (fixing roller rotating bodies) 31 and 32 . A fixing heater is arranged inside one fixing roller 31 , and a pressure spring and a pressure arm are arranged around the other fixing roller 32 . One fixing roller 31 is pressed against the other fixing roller 32 by the pressure spring and the pressure arm. A thermistor and a thermostat are arranged on one fixing roller 31 .

The fixing heater measures the temperature of the fixing roller 31 with a thermistor and turns the fixing heater on or off with a thermostat to keep one of the fixing rollers 31 at a predetermined temperature.

Further downstream of the fixing device 22 in the sheet conveying direction, an ejection branch claw 34, an ejection roller 35, a first pressure roller 36, a second pressure roller 37, and a stiff roller 38 are arranged. A discharge stacking section (discharge position) 39 for stacking the sheets is arranged.

A laser writing device 47 is arranged on the left side of the developing device 12 in the drawing. The laser writing device 47 includes a laser light source, a rotating polygonal mirror 48 for scanning, a polygon motor 49, a scanning optical system 50 such as an fθ lens, and the like.

The image reader 3 includes a light source 53, a plurality of mirrors 54, an imaging optical lens 55, an image sensor 56 such as a CCD, and the like, and a contact glass 57 is arranged on the upper surface.

One end of the automatic document feeder 5 is connected to one end of the upper surface of the image reading device 3 by a joint having a hinge structure. The automatic document feeder 5 changes from a horizontal state in which the lower surface presses a document sheet placed on the upper surface of the contact glass 57 from above to a state in which the inclination angle with the upper surface of the contact glass 57 is 90 degrees at maximum. It is provided so that it can be opened and closed freely. The automatic document feeder 5 is provided with a loading table at the document loading position and a discharge table at the discharging position, and discharges the sheet such as the document from the loading table through the reading position on the contact glass 57 of the image reading device 3. A sheet conveying device having a document conveying path for conveying to a table is provided. The sheet conveying device includes a plurality of sheet conveying rollers (sheet conveying rotators) for conveying sheets such as originals.

The sheet feeding device 4 includes multiple stages of sheet separating devices 61 at which the sheets S are supplied. Each sheet separation device 61 has a pickup roller (feeding roller) 62, a feed roller (feeding roller) 63, and a reverse roller (separation roller) 64 corresponding to each other. A supply path R1 leading to the sheet conveying path R of the image forming apparatus main body 2 is formed on the right side of the sheet separation device 61 arranged in multiple stages in the figure. The supply path R1 includes several sheet conveying rollers (sheet conveying rotators) 66 for conveying sheets.

The switchback device 42 is arranged on the right side of the image forming apparatus main body 2 in the figure. The switchback device 42 includes a sheet conveying device D2 branching from the position of the discharge branch claw 34 of the sheet conveying path R. As shown in FIG. The sheet conveying device D2 has a reversing path R3 leading to a switchback position 44 where a pair of switchback rollers 43 are arranged, and a re-conveying path R4 leading from the switchback position 44 to the registration rollers 21 of the sheet conveying path R again. have. Further, the sheet conveying device D2 has a plurality of sheet conveying rollers (sheet conveying rotators) 66 for conveying sheets. In this embodiment, the switchback device 42 is configured to be attached to an opening/closing member 71 to be described later.

The manual paper feeding device 70 is arranged on the right side of the image forming apparatus main body 2 in the drawing. The manual sheet feeding device 70 includes a pickup roller (feeding roller) 67A, a feed roller (feeding roller) 67B, and a reverse roller (feeding roller) 67C. No. 2 sheet conveying path R is supplied.

Next, the operation of copying machine 1 will be described.
First, in order to generate a copy using the copier 1, the main switch is turned on and the document is set on the automatic document feeder 5. As shown in FIG. Or, open the automatic document feeder 5, set the document directly on the contact glass 57 of the image reader 3, close the automatic document feeder 5, and press it.

When the start switch is pressed, when the document is set on the automatic document feeder 5, the document is moved by the sheet transport roller through the document transport path onto the contact glass 57, and then the image reading device 3 is driven. The contents of the document are read and discharged onto the discharge tray. On the other hand, when the document is set directly on the contact glass 57, the image reading device 3 is immediately driven.

When the image reading device 3 starts driving, the light source 53 moves along the contact glass 57 while emitting light to irradiate the document surface on the contact glass 57 with light. A plurality of mirrors 54 receive reflected light from the document surface and reflect the light toward an imaging optical lens 55 . The imaging optical lens 55 forms an image of this reflected light on the image sensor 56 . Thereby, the image sensor 56 reads the content of the document.

At the same time, the photoreceptor 10 is rotated by the photoreceptor driving motor, and along with this, the surface of the photoreceptor is uniformly charged by the charging device 11 using the charging roller, and then the laser writing device 47 is operated as described above. Writing is performed on the surface of the photoreceptor by irradiating the surface of the photoreceptor with laser light in accordance with the content of the document read by the image reading device 3 , thereby forming an electrostatic latent image on the surface of the photoreceptor 10 . . After that, when the electrostatic latent image formed on the surface of the photoreceptor faces the developing device 12, toner is attracted to the surface of the photoreceptor, and the electrostatic latent image is visualized.

Further, when the start switch is pushed, the corresponding paper separating device 61 is selected from among the plurality of paper separating devices 61 arranged in multiple stages in the paper feeding device 4 based on the paper size selection signal. Then, a pickup roller 62 corresponding to this paper separation device 61 feeds out one sheet S in this paper separation device 61 . The reverse roller 64 separates the uppermost sheet S and prevents the rest of the sheets S from being conveyed when the plurality of sheets S is to be sent out. Subsequently, the feed roller 63 conveys the sheet S into the supply path R1, the sheet conveying roller 66 continues conveying the sheet S and guides it to the sheet conveying path R, and the registration roller 21 comes into contact with the sheet S, causing the sheet S to move. stop transport. Then, the registration roller 21 rotates in synchronization with the rotation of the photoreceptor 10 described above, and feeds the sheet S to the right side of the photoreceptor 10 .

When manual paper feeding is performed, the manual feed tray 72 of the manual feed device 70 is shifted from the upright closed state to the tilted open state shown in FIG. Place a sheet on top. When the start switch is pressed, the pickup roller 67A feeds one sheet, and subsequently the feed roller 67B takes over feeding of the sheet. The reverse roller 67C separates the uppermost sheet when sending out a plurality of sheets, and prevents the rest of the sheets from being conveyed. The sheet conveying roller 66 continues to convey the sheet supplied to the manual feed path R<b>2 and guides it to the sheet conveying path R. After that, the registration rollers 21 feed the sheet to the right side of the photoreceptor 10 in synchronization with the rotation of the photoreceptor 10, in the same manner as the paper feeding device 4 described above.

Next, when the sheet S fed to the right side of the photoreceptor 10 reaches the transfer position T, the transfer device 13 transfers the toner image on the photoreceptor 10 to the sheet S to form an image. The cleaning device 14 removes and cleans the residual toner on the photoreceptor 10 after image transfer, and then the static elimination device removes the residual potential on the photoreceptor 10 to prepare for the next image formation starting from the charging device 11. .

Next, the fixing device 22 conveys the sheet S onto which the toner image has been transferred by the transfer belt 17, passes it between a pair of fixing rollers 31 and 32, and applies heat and pressure at the fixing position to fix the transferred image. . The sheet S on which the fixing has been performed is then flattened and stiffened in the course of passing through the first pressure roller 36, the discharge roller 35, the second pressure roller 37, and the stiffness roller 38, and is discharged and stacked. 39 and stacked there.

When images are transferred to both sides of the sheet S, the discharge branch claw 34 is switched. Then, the sheet S having the image transferred to its surface is fed from the sheet conveying path R into the reversing path R3, conveyed by the sheet conveying rollers 66 to the switchback position 44, and switched back at the switchback position 44. FIG. After that, the sheet is put into the re-conveying path R4, reversed, conveyed by the sheet conveying roller 66, guided again to the sheet conveying path R, and the image is transferred to the rear surface of the sheet in the same manner as described above.

FIG. 2 is an external perspective view showing the manual sheet feeder 70. As shown in FIG.
As shown in FIG. 1, the manual sheet feeding device 70 of the present embodiment includes an opening/closing member 71 having a rotation fulcrum 71A at its lower portion with respect to the image forming apparatus main body 2 and opening and closing the upper portion of the opening/closing member 71. It has a manual feed tray 72 whose upper part opens and closes with a rotation fulcrum 72A at its lower part. Further, as shown in FIG. 2, the manual paper feeding device 70 includes a link member 73 that connects the opening/closing member 71 to the image forming apparatus main body 2 so that the opening/closing member 71 can be opened and closed.

In order to remove a jammed sheet jammed in the sheet conveying path R or the re-conveying path R4, or to easily perform maintenance inside the image forming apparatus main body 2, the openable/closable member 71 is placed in an open state in an inclined posture and the sheet conveying path is opened. R and the re-conveyance path R4 are opened. That is, the manual sheet feeder 70 opens the sheet conveying path R and the re-conveying path R4 by changing the opening/closing member 71 from the upright closed state to the tilted open state to open the sheet conveying path R and the re-conveying path R4. can be done easily.

The manual feeder 70 also changes the manual feed tray 72 from the upright, closed state to the tilted, open state (see FIG. 1) and stacks the sheets on the sheet stacking surface 72B of the manual feed tray 72. A sheet can be supplied to the sheet transport path R.

FIG. 3 is a perspective view of the manual feed tray according to this embodiment.
As shown in FIG. 3, the manual feed tray 72, which is a sheet holding device, is provided with side fences 74A and 74B and a guide rail 75. As shown in FIG. The side fences 74A and 74B are installed in the sheet width direction (Y direction) in the space above the sheet stacking surface 72B (the stacking space for the sheets S).

The manual feed tray 72 of the present embodiment is provided with a guide rail 75 as a guide portion extending in the sheet width direction (Y direction). A pair of side fences 74A and 74B, which are respectively installed at both ends in the width direction of the sheet S so as to sandwich the sheet S, extend along the guide rail 75 toward and away from the ends of the width direction of the sheet S (in the width direction of the sheet). ), and is positioned according to the size of the sheet S in the width direction. That is, the side fences 74A and 74B function as regulating members that regulate the position of the sheet S in the width direction.

In the manual feed tray of this embodiment, an end fence may be provided on the upstream side in the sheet feeding direction (X direction) in the space above the sheet stacking surface 72B (the space for stacking the sheets S). Specifically, for example, a guide rail, which is a guide portion, is provided on the manual feed tray 72 so as to extend in the sheet feeding direction (X direction), and the end fence is movable in the sheet feeding direction along the guide rail. Install. The end fence is positioned according to the size of the sheet S placed on the sheet stacking surface 72B in the feeding direction. That is, the end fence functions as a regulating member that regulates the end position of the sheet S in the feeding direction.

In this embodiment, the pair of side fences 74A and 74B are configured to interlock with each other to increase or decrease the interval in the width direction. That is, when one side fence 74A, 74B is manually moved in the +Y direction, the other side fence 74B, 74A moves in the -Y direction in conjunction with it. Also, when one side fence 74A, 74B is manually moved in the -Y direction, the other side fence 74B, 74A moves in conjunction with it in the +Y direction.

In FIG. 3, the feeding direction of the sheet S is the X direction, and the manual feed tray 72 can be inserted and removed in the Y direction, but the present invention is not limited to these directional relationships.

FIG. 4 is a plan view showing the movement mechanism of the side fences 74A and 74B in the manual feed tray 72 of this embodiment.
The movement mechanism of the side fences 74A and 74B in this embodiment is configured to move the pair of side fences 74A and 74B so that the center of the sheet S in the width direction coincides with the center of the bottom plate 24 in the width direction even if the size of the sheet S in the width direction changes. are configured to move in conjunction with each other. In this embodiment, a pinion and rack mechanism is used as a movement mechanism for the side fences 74A and 74B.

Specifically, as shown in FIG. 4, the side fences 74A and 74B are provided with racks 81A and 81B, respectively. Each of the racks 81A and 81B meshes with a pinion 82 arranged substantially in the center in the seat width direction so as to sandwich the pinion 82 from both sides. As a result, when one of the side fences 74A, 74B is moved in the seat width direction, the racks 81A, 81B of the side fences 74A, 74B are interlocked and moved in the seat width direction, causing the pinion 82 to rotate. The rotation of the pinion 82 causes the other racks 81B and 81A to move in the cross direction along the seat width direction, and in conjunction with this, the other side fences 74B and 74A move in the seat width direction.

In this embodiment, a gear (rotating member) 84 is meshed with one rack 81A. A rotating shaft 84a of the gear 84 is fitted into an engaging hole 83b formed in a rotor (member to be detected) 83a of the rotary sensor 83 and connected thereto. For example, when the user moves the side fence 74A in the seat width direction, the rack 81A of the side fence 74A moves in the seat width direction in conjunction with the side fence 74A to rotate the gear 84 meshing with the rack 81A. As a result, the rotor 83a of the rotary sensor 83 connected to the gear 84 rotates integrally with the gear 84, and the rotary sensor 83 detects the amount of rotation of the rotor 83a. The detection result of the rotary sensor 83 (the amount of rotation of the rotor 83a) is sent to the control section of the image forming apparatus, and is used to determine the width direction size of the sheet S set on the manual feed tray 72, for example.

FIGS. 5A to 5C are explanatory diagrams when there is a discrepancy between the detection result of the rotary sensor 83 (the amount of rotation of the rotor 83a) and the amount of rotation of the gear 84 (the positions of the side fences 74A and 74B). .
In the present embodiment, the rotor 83a of the rotary sensor 83 and the gear 84 are connected by making the rotation shaft 84a of the gear 84 into a D-cut shaft and forming an engagement surface that engages with the D-cut surface (abutting portion) 84b. The engagement hole 83b of the rotor 83a is formed in a D-cut shape so that the inner wall flat portion (abutted portion) 83c is formed so that the rotor 83a and the gear 84 rotate integrally.

Here, in such a connection structure, as shown in FIG. A gap C may occur between the D-cut surface 84b and the inner wall plane portion 83c of the engaging hole 83b. If such a gap C exists, the contact state between the D-cut surface 84b formed on the rotary shaft 84a of the gear 84 and the inner wall flat portion 83c of the engagement hole 83b of the rotor 83a cannot be uniquely determined.

Specifically, when the side fences 74A and 74B are moved in a direction to increase the distance between them, as shown in FIG. , and rotates relative to the engaging hole 83b of the rotor 83a by the gap C. As shown in FIG. As a result, one end side of the D-cut surface 84b in the direction perpendicular to the axial direction of the rotating shaft 84a of the gear 84 (the right end portion in the drawing) is aligned with one end side of the inner wall flat portion 83c of the engagement hole 83b of the rotor 83a. (right end in the figure), the other end of the D-cut surface 84b and the other end of the inner wall plane portion 83c are separated from each other. In this abutting state, compared with the state in which the D-cut surface 84b and the inner wall plane portion 83c are parallel, the rotational position in which the gear 84 is rotated by an angle of -θ° relative to the rotor 83a. Take.

Further, when the side fences 74A and 74B are moved in the direction of narrowing the distance between them, as shown in FIG. It rotates and rotates relative to the engaging hole 83b of the rotor 83a by the amount of the gap C. As shown in FIG. As a result, the other end of the D-cut surface 84b in the direction orthogonal to the axial direction of the rotating shaft 84a of the gear 84 (the left end in the drawing) is the inner wall flat portion 83c of the engagement hole 83b of the rotor 83a. While contacting the end side (the left end in the figure), the one end side of the D-cut surface 84b and the one end side of the inner wall plane portion 83c are separated from each other. In this abutment state, the gear 84 rotates relative to the rotor 83a by an angle of +θ° compared to the state in which the D-cut surface 84b and the inner wall plane portion 83c are parallel to each other. .

As a result of the above, even if the positions of the side fences 74A and 74B are the same, the angle detected by the rotary sensor 83 can vary within the angle range of 2θ°. In particular, an angle difference of up to 2θ° occurs between when the side fences 74A and 74B are moved in the direction of widening the distance between them and when they are moved in the direction of narrowing the distance therebetween. Therefore, the rotation amount (rotation angle) of the gear 84 cannot be accurately obtained from the detection result (rotation amount of the rotor 83a) of the rotary sensor 83, and the positions of the side fences 74A and 74B cannot be accurately grasped. Therefore, for example, when determining the width direction size of the sheet S from the detection result of the rotary sensor 83 (rotation amount of the rotor 83a), the determination cannot be performed appropriately.

FIG. 6 is an explanatory view showing a connecting structure between the rotation shaft 84a of the gear 84 and the engagement hole 83b of the rotor 83a in this embodiment.
In this embodiment, the contact between the gear 84 and the rotor 83a is maintained so that the D-cut surface 84b of the rotation shaft 84a of the gear 84 and the inner wall plane portion 83c of the engagement hole 83b of the rotor 83a are kept in contact with each other. A spring 85 is provided as an urging member for applying an urging force in the rotational direction.

In the present embodiment, in order to mount the spring 85 inside the engagement hole 83b of the rotor 83a, a notch is provided in the rotating shaft 84a of the gear 84 to remove a part of the D-cut surface 84b to provide a space for mounting the spring 85. forms a G.

The biasing member is not particularly limited as long as it can apply the biasing force as described above. The biasing member of this embodiment is attached inside the engagement hole 83b of the rotor 83a, but the installation location is not limited to this.

The spring 85 of the present embodiment applies an urging force in the direction of symbol F in FIG. portion) is urged in a direction away from the inner wall flat portion 83c of the engaging hole 83b. Due to this urging force, the contact state between the D-cut surface 84b and the inner wall flat portion 83c of the engagement hole 83b is always maintained in the contact state (the biased state) shown in FIG. 5(c).

Since the biasing force of the spring 85 is set to be equal to or greater than the rotational torque of the rotor 83a, as shown in FIG. The contact state between the D-cut surface 84b and the inner wall flat portion 83c of the engagement hole 83b is maintained in the contact state shown in FIG. rotate to Therefore, even if there is a gap C between the D-cut surface 84b of the rotating shaft 84a and the inner wall flat portion 83c of the engaging hole 83b, the contact between the D-cut surface 84b and the inner wall flat portion 83c of the engaging hole 83b will be minimized. The contact state is uniquely determined, and the amount of rotation (angle of rotation) of the gear 84 can be accurately obtained from the detection result of the rotary sensor 83 (the amount of rotation of the rotor 83a). As a result, the position of the side fences 74A and 74B can be accurately grasped from the detection result of the rotary sensor 83 (the amount of rotation of the rotor 83a). When determining the size, the determination can be performed appropriately.

On the other hand, the biasing force of the spring 85 in this embodiment is set to be less than the allowable damage pressure of the rotor 83a. Therefore, when the gear 84 is attached to the rotor 83a, an excessive external force that exceeds the allowable damage pressure of the rotor 83a is not applied, and the rotary sensor 83 is less likely to malfunction or be damaged.

Further, in the present embodiment, a gap C is allowed to exist between the D-cut surface 84b of the rotating shaft 84a and the inner wall plane portion 83c of the engagement hole 83b of the rotor 83a. Therefore, there is no need to adopt a connection structure in which the rotating shaft 84a of the gear 84 is press-fitted into the engagement hole 83b of the rotor 83a, and excessive external force is not applied to the rotary sensor 83 due to the press-fitting. There is less worry about the sensor 83 malfunctioning or breaking.

Next, the configuration of the spring 85 will be further described.
FIG. 7 is a perspective view showing a state where the rotating shaft 84a of the gear 84 is fitted into the engagement hole 83b of the rotor 83a of the rotary sensor 83 and the spring 85 is not yet attached.
The spring 85 of the present embodiment applies an urging force by a restoring force against deformation of a wire made of metal or the like. Specifically, as shown in FIG. 7, when the wire has one or more bent portions 85a, 85b, and 85c that are bent, and the bent portions 85a, 85b, and 85c are deformed in the closing direction or the opening direction, biasing force is applied by the restoring force of The bent portions 85a, 85b, 85c are rounded to avoid stress concentration during elastic deformation.

One end of the wire constituting the spring 85 of this embodiment is provided with a grasping portion 86 for a worker to grasp when assembling the spring 85, and the other end is a free end. In this embodiment, the outer shape of the grip portion 86 is circular so that the operator can easily hold it. As long as the outer shape is circular, it may be a disk member or an annular member. The outer shape of the grip portion 86 is not limited to a circular shape, and may be other outer shapes.

FIG. 8(a) is an explanatory diagram showing the shape of the spring 85 before assembly, and FIG. 8(b) is an explanatory diagram showing the shape of the spring 85 after assembly.
When assembling the spring 85, the operator grips the spring 85 by pinching the grip portion 86 between two fingers. Then, the operator moves the spring 85 in the direction of the central axis of the gripping portion 86 (vertical direction in the figure) so that the bent end portion 85a of the spring 85 is formed by the notch of the rotating shaft 84a of the gear 84. 7 from the axial direction of the rotating shaft 84a into the space G in the engaging hole 83b of the rotor 83a. The spring 85 is inserted from the axial end face of the gear 84 opposite to the side facing the rotary sensor 83 .

Here, the first linear portion 85d between the first bent portion 85b of the spring 85 and the fixed end of the wire (the end of the wire to which the gripping portion 86 is attached) is substantially parallel to the central axis direction of the circular gripping portion 86. extends to Therefore, when the spring 85 is inserted, the first linear portion 85d advances straight along the surface of the rotating shaft 84a forming the space G in the rotating direction of the rotating shaft 84a. On the other hand, the second linear portion 85e between the second bent portion 85c of the spring 85 and the free end of the wire (the end opposite to the fixed end of the wire) is, as shown in FIG. It extends in a direction inclined away from the first straight portion 85 d with respect to the central axis direction of the grip portion 86 so that the overall shape of the grip portion 85 is substantially V-shaped. Therefore, when the spring 85 is inserted, the second linear portion 85e contacts the inner wall flat portion 83c of the rotor 83a that forms the space G in the rotation direction of the rotating shaft 84a. As a result, the spring 85 is elastically deformed so that the second linear portion 85e approaches the first linear portion 85d.

Further, along with this elastic deformation, the bent tip portion 85a of the spring 85 moves to a position where it wraps around to the back side of the rotor 83a (the tip side in the spring insertion direction). As a result, in the spring 85, as shown in FIG. 8B, the bent tip portion 85a is located outside the space G in the plane direction (horizontal direction in the drawing) orthogonal to the axial direction of the rotation shaft 84a. held in position. As a result, the third linear portion 85f between the tip bent portion 85a and the second bent portion 85c is caught on the back side of the rotor 83a, preventing the spring 85 from easily coming out of the space G.

The configuration as described above is realized by the shape of the spring 85 of this embodiment. That is, in the shape of the spring 85 of the present embodiment before assembly, as shown in FIG. extends to The interval D2 between the first straight portion 85d and the third straight portion 85f is set narrower than the interval D1 of the space G. Moreover, as shown in FIG. 8B, the shape of the spring 85 of the present embodiment after assembly is such that the maximum distance between the spring portions wrapped around the back side of the rotor 83a, that is, the first straight portion 85d and the tip bent portion 85a is set wider than the interval D1 of the space G.

FIG. 9 is a perspective view, partly in section, showing a state in which the rotating shaft 84a of the gear 84 is fitted into the engaging hole 83b of the rotor 83a of the rotary sensor 83 and the spring 85 is attached.
The cross section shown in FIG. 9 is taken along the line WW in FIG.

FIG. 10 is a perspective view showing the gear 84 alone.
FIG. 11 is an enlarged view of a portion of the gear 84 provided with a canopy portion 87 that prevents the spring 85 from leaving the space G. As shown in FIG.
12 is a perspective view showing a partial cross section of the gear shown in FIG. 11. FIG.
In this embodiment, an eaves portion 87 is provided as a detachment prevention member that prevents the spring 85 attached to the space G from being detached from the space G. As shown in FIG. The canopy portion 87 is provided on the axial end face of the gear 84 on the side where the spring 85 is inserted, that is, the end face on the side opposite to the side facing the rotary sensor 83 . The eaves portion 87 has one end fixed to the axial end face of the gear 84 and the other end protruding toward the rotating shaft 84 a of the gear 84 . A spring 85 is inserted into the space G through a spring receiving opening G′ provided in the gear 84 . When the spring 85 is inserted into the space G, the protruding part of the eaves part 87 abuts against the grip part 86 of the spring 85 from the rear side in the insertion direction, thereby preventing the spring 85 from leaving the space G. . When inserting the spring 85 , it is possible to get over the overhanging portion of the eaves portion 87 by elastically deforming the gripping portion 86 with a finger.

The connection between the rotor 83a of the rotary sensor 83 and the gear 84 in this embodiment is achieved by making the rotating shaft 84a of the gear 84 into a D-cut shaft, making the engagement hole 83b of the rotor 83a into a D-cut shape, and connecting the rotor 83a and the gear. 84 rotate integrally. At this time, as shown in FIG. 13(b), when the length x of the D-cut surface 84b in the cross section orthogonal to the axial direction of the rotating shaft 84a of the gear 84 becomes X/2 or less, the rotor 83a and the gear 84 cannot rotate as one. Therefore, the length x of the D-cut surface 84b is set so that the rotor 83a and the gear 84 can rotate together as shown in FIG. 13(a).

FIG. 14 is a perspective view of the rotary sensor 83 with the gear 84 removed.
15 is a perspective view of a state in which the rotary sensor 83 is removed from the base 72C of the manual feed tray 72. FIG.
FIG. 16 is a plan view of the rotary sensor 83 with the gear 84 removed.
FIG. 17 is a perspective view showing a partial cross section of the rotary sensor 83 to which the gear 84 is attached and its periphery.
FIG. 18 is a cross-sectional view of the vicinity of the meshing portion between the gear 84 and the rack 81A.

The rotary sensor 83 of this embodiment is mounted on a sensor substrate 88 that is placed on the base 72</b>C of the manual feed tray 72 . The sensor board 88 is positioned on the base 72C by a main positioning reference boss 89a and a secondary positioning reference boss 89b on the base 72C.

Here, when the side fence 74A moves, the gear 84 meshing with the rack 81A moving in conjunction with the side fence 74A flaps. If the degree of fluttering (displacement of the gear 84) is large, the engagement between the rack 81A and the gear 84 will be disengaged, and the corresponding relationship between the side fence 74A and the amount of rotation of the rotor 83a to which the gear 84 is attached will be broken, resulting in manual feeding. It becomes impossible to appropriately determine the width direction size of the sheet S set on the tray 72 .

Therefore, on the base 72C of the present embodiment, as shown in FIG. Suppression bosses 89c, 89d, 89e and 89f are provided. As shown in FIGS. 14 and 16, the sensor substrate 88 is formed with holes and cutouts corresponding to the flapping suppression bosses 89c, 89d, 89e, and 89f.

The sensor substrate 88 is mounted on the base 72C so that the holes and cutouts of the sensor substrate 88 are engaged with the flapping suppression bosses 89c, 89d, 89e, and 89f, thereby fixing the gear 84 to the sensor substrate 88. is regulated. As a result, rattling of the gear 84 is suppressed when the side fence 74A is moved.

[Modification 1]
Next, a modified example of the spring in this embodiment (this modified example is hereinafter referred to as “modified example 1”) will be described.
In the spring 85 of the embodiment described above, when the spring 85 is inserted into the space G formed by providing the notch in the rotation shaft 84a of the gear 84, as shown in FIG. , and the spring 85 is elastically deformed so that the second linear portion 85e approaches the first linear portion 85d. At this time, the second linear portion 85e of the spring 85 receives a resistance E against the restoring force (elastic force) of elastic deformation of the spring 85 from the inlet edge portion 83d of the space G, as shown in FIG. This drag force E has a force component Ea in the opposite direction (upper side in FIG. 19) to the insertion direction of the spring 85, so it acts to pull the spring 85 out of the space G. Therefore, when the spring 85 is inserted (at the time of assembly), the elastic force of the spring 85 may cause the spring 85 to pop out of the space G and escape.

Also, if the spring 85 is assembled with insufficient insertion, the elastic force of the spring 85 will cause the spring 85 to deviate from the space G after assembly, causing a gap between the gear 84 and the rotor 83a in the rotational direction. There is a possibility that a sufficient biasing force cannot be applied.

FIG. 20(a) is an explanatory diagram showing the shape of the spring 185 before assembly in Modification 1, and FIG. 20(b) is an explanatory diagram showing the state of the spring 185 during assembly. FIG. 20(c) is an explanatory diagram showing the shape of the spring 185 after assembly.

In Modification 1, as shown in FIG. 20(a), the operator inserts the bent end portion 85a of the spring 185 into the space G of the rotor 83a. Here, in the spring 185 of Modification 1, the fourth straight portion 85f1 and the fifth straight portion 85f1 and the fifth A linear portion 85f2 and a third bent portion 85f3 connecting them are provided. As a result, before the second straight portion 85e comes into contact with the entrance edge portion 83d of the space G of the rotor 83a and receives the resistance E against the restoring force (elastic force) of the elastic deformation of the spring 185, as shown in FIG. As shown, tip bend 85a of spring 185 can clear exit edge 83e of space G. FIG.

As described above, the spring 185 of Modification 1 has already reached the exit edge 83e of the space G when the spring 185 receives the drag force E against the restoring force (elastic force) of the elastic deformation of the spring 185 . will exceed Therefore, at this point, by inserting the spring 185 into the space G while operating the grasping portion 86 so as to rotate in the direction of arrow H in FIG. The spring 185 can be elastically deformed so that the second linear portion 85e approaches the first linear portion 85d while being hooked on the back side. Therefore, even if the spring 185 receives a drag force E having a component force Ea in a direction opposite to the insertion direction, the spring 185 is prevented from jumping out of the space G by being caught by the fourth straight portion 85f1. be able to.

[Modification 2]
Next, a modified example of the grip portion of the present embodiment (this modified example is hereinafter referred to as “modified example 2”) will be described.
FIG. 21 is a perspective view showing a grip portion 186 in Modification 2. As shown in FIG. 21 is a perspective view, partly in cross section, showing a state in which the rotation shaft 84a of the gear 84 is fitted into the engagement hole 83b of the rotor 83a of the rotary sensor 83 and the spring 85 is attached, as in FIG. is.

The gripping portion 86 of the above-described embodiment is configured by a member separate from the spring 85, but in the present modified example 2, one end side of the wire configuring the spring 85 is wound into a coil shape. . As a result, the number of parts is reduced compared to the case where the gripping portion is formed of a member separate from the spring 85, which is advantageous for cost reduction.

However, in Modification 2, the grip portion 186 is formed by winding one end of the wire that constitutes the spring 85 into a coil shape, so the following problems are likely to occur. That is, even after the assembly, the second straight portion 85e of the spring 85 receives the resistance E against the restoring force (elastic force) of the elastic deformation of the spring 85 from the inlet edge portion 83d of the space G, and the spring 85 escapes from the space G. A force that shifts in the direction may act.

Normally, even if such a force acts, the third linear portion 85f of the spring 85 is caught on the back side of the rotor 83a, and the protruding portion of the eaves portion 87 presses against the grip portion 186 of the spring 85. The spring 85 is prevented from coming out of the space G. However, in the case of using the grip portion 186 which is coiled by winding one end of the wire that constitutes the spring 85, if the spring 85 is displaced from the space G after assembly, the spring 85 may be displaced by the force. and the grip portion 186 is lifted, and as shown in FIG. In this state, even if the protruding portion of the eaves portion 87 presses the grip portion 186 of the spring 85, the spring 85 moves in the direction to get out of the space G by the amount that the connecting portion 85g is lifted. The hooking of the third linear portion 85f to the rear side of the rotor 83a is insufficient. As a result, there is a possibility that a sufficient biasing force in the rotational direction cannot be applied between the gear 84 and the rotor 83a.

Further, when the engagement of the third linear portion 85f of the spring 85 with the rear side of the rotor 83a is insufficient, the gear 84 is pulled out of the engagement hole 83b of the rotor 83a of the rotary sensor 83 at the rotating shaft 84a of the gear 84. easier to move in any direction. As a result, when the side fence 74A moves, if the gear 84 meshing with the rack 81A moving in conjunction with the side fence 74A flaps, the gear 84 and the rack 81A may become disengaged.

Therefore, when using the holding part 186 which is coiled by winding one end of the wire constituting the spring 85 as in the present modified example 2, the shape of the spring 185 as shown in the modified example 1 is adopted. You may That is, the bent end portion 85a of the spring 185 is already over the outlet edge portion 83e of the space G at the time when the resistance E against the restoring force (elastic force) of the elastic deformation of the spring 185 is received. According to this, even if the spring 185 receives a resistance E against the restoring force (elastic force) of the elastic deformation of the spring 185, the fourth linear portion 85f1 of the spring 185 is caught on the back side of the rotor 83a. The connecting portion 85g is not lifted up, and the winding direction of the wire constituting the grip portion 186 is not reversely wound. Therefore, even if the gear 84 meshing with the rack 81A moving in conjunction with the side fence 74A flutters when the side fence 74A moves, the gear 84 and the rack 81A are prevented from being disengaged.

As described above, in the present embodiment (including modifications; the same applies hereinafter), the configuration in which the two side fences 74A and 74B move in conjunction with each other has been described. Also, the present invention can be similarly applied to a configuration in which only one of the side fences 74A, 74B moves.

Further, in the present embodiment, a case has been described in which the side fences 74A and 74B contact and separate from the sheet edges along the sheet width direction orthogonal to the sheet conveying direction. You may apply this invention with respect to the end fence which touches and separates from a part.

In this embodiment, the gear 84 side is a D-cut shaft and the rotor 83a side is a D-cut engagement hole. The gear 84 side may be a D-shaped engagement hole.

In addition, although the manual feed tray 72 has been described in the present embodiment, any device that holds sheets is not limited to the manual feed tray 72. The sheet storage section, the discharge stack section 39, and the sheet separation device 61 of the paper feeding device 4 may be used. The present invention can also be applied to the mounting table of the automatic document feeder 5 or the like.

What has been described above is only an example, and each of the following aspects has a specific effect [first aspect]
A first mode includes a regulating member (e.g., side fences 74A and 74B) that can move in a direction toward and away from an end of a sheet (e.g., sheet S), and a rotating member ( gear 84), a member to be detected (for example, rotor 83a) that is attached to the rotating member and rotates integrally, and rotational position detection means (for example, rotary sensor 83) that detects the rotational position of the member to be detected. In the sheet holding device (for example, the manual feed tray 72) provided, the contact portion (for example, the D cut surface 84b) of the rotating member is in contact with the contact portion (for example, the inner wall flat portion 83c) of the member to be detected. The member to be detected rotates integrally with the rotating member by coming into contact with the rotating member in the rotating direction, and the contacting portion and the contacted portion are kept in contact with each other. It is characterized by having an urging member (such as a spring 85) that applies a force F between the rotating member and the member to be detected.
In order to connect the rotating member and the member to be detected, generally, the shaft provided on one of the rotating member and the member to be detected is a D-cut shaft, and the D-cut surface (abutment portion or abutted portion) is engaged. A structure in which the other hole has a D-cut shape is often adopted so that a mating inner wall surface (abutted portion or abutting portion) is formed. However, in this structure, a gap C may occur between the D-cut surface and the inner wall surface of the hole due to dimensional variations in the D-cut hole and the D-cut shaft fitted therein. If such a gap exists, the relationship between the rotation angle of the rotating member and the rotation angle of the member to be detected cannot be uniquely determined, and the rotation angle of the rotating member cannot be obtained accurately from the rotation angle of the member to be detected. As a result, the position of the regulating member cannot be accurately grasped, and the sheet size cannot be properly determined.
In this aspect, the contact state between the contact portion of the rotating member and the contact portion of the member to be detected is maintained by the biasing force applied by the biasing member. As a result, even if there is a gap C between the contact portion of the rotating member and the contact portion of the member to be detected, the contact portion of the rotating member and the contact portion of the member to be detected are in contact with each other. As a result of maintaining the state, the relationship between the rotation angle of the rotating member and the rotation angle of the member to be detected is uniquely determined. Therefore, the rotation angle of the rotating member can be detected with high accuracy, and the position of the regulating member can also be detected with high accuracy. Therefore, for example, when detecting the size of the sheet according to the position of the regulating member, it is possible to detect the size of the sheet with high accuracy.
Moreover, in this aspect, even if there is a gap between the contact portion of the rotating member and the contacted portion of the member to be detected, the rotation angle of the rotating member can be detected with high accuracy. This eliminates the need to adopt a connection structure that press-fits the member and the member to be detected. In such a connection structure by press-fitting, an excessive external force is applied to the rotational position detecting means through the member to be detected during the press-fitting, and there is concern that the rotational position detecting means may malfunction or be damaged. No more worries.

[Second aspect]
A second aspect is, in the first aspect, having a rotating shaft 84a provided on one of the rotating member and the member to be detected, and an engaging hole 83b engaged with the rotating shaft provided on the other. One of the contact portion and the contacted portion is formed on the peripheral surface of the rotating shaft, and the other is formed on the inner wall surface of the engagement hole, and the biasing member is attached inside the engagement hole. It is characterized by being
According to this, since the biasing member is attached inside the engagement hole, the biasing member is less likely to be an obstacle.

[Third aspect]
A third aspect is the second aspect, wherein the rotating shaft is a D-cut shaft, and the abutting portion or the abutted portion formed on the peripheral surface of the rotating shaft is a D-cut surface of the D-cut shaft. 84b, and the abutted portion or the abutting portion formed on the inner wall surface of the engagement hole is an engaging surface (for example, inner wall flat portion 83c) that engages with the D-cut surface. and
According to this, in a joint structure using a generally adopted D-cut shaft, there is no fear of failure or damage of the rotational position detection means due to press fitting, and the rotation angle of the rotating member can be accurately determined from the detection result of the rotational position detection means. well detectable.

[Fourth aspect]
According to a fourth aspect, in the third aspect, the biasing member biases one end side of the D-cut surface in a direction perpendicular to the axial direction of the rotating shaft in a direction away from the engaging surface. and
According to this, the contact state between the contact portion of the rotary member and the contact portion of the member to be detected is always kept in a biased state, and the contact state can be maintained with a simple configuration.

[Fifth aspect]
A fifth aspect is characterized in that, in the fourth aspect, the biasing member is a spring member (e.g., spring 85) that applies the biasing force by restoring force against deformation of the wire.
According to this, it is easy to install the biasing member even in a narrow space.

[Sixth aspect]
According to a sixth aspect, in the fifth aspect, the spring member has one or more bent portions 85a, 85b, 85c formed by bending the wire, and the bent portions are deformed in the closing direction or the opening direction. It is characterized in that the urging force is applied by the restoring force when it is folded.
According to this, an urging member that can be easily installed in a narrow space can be realized with a simple configuration.

[Seventh aspect]
According to a seventh aspect, in the sixth aspect, the spring member is attached such that at least one bent portion (for example, a tip bent portion 85a) passes through the engagement hole, and the bent portion extends through the rotation axis. It is characterized in that it is held in a posture positioned outside the engaging hole in a plane direction perpendicular to the axial direction of the.
According to this, the spring member inserted into the engagement hole can be hooked on the edge of the engagement hole so that the spring member does not easily slip out of the engagement hole.

[Eighth aspect]
In an eighth aspect based on the seventh aspect, the spring member inserts the bent portion into the engagement hole when the spring member is attached, and when the spring member generates the biasing force, the bent portion passes through the engagement hole.
According to this, it is possible to prevent the spring member inserted into the engagement hole from coming off easily from the engagement hole.

[Ninth aspect]
A ninth aspect is any one of the second to eighth aspects, and has a detachment prevention member (e.g., eaves 87) that prevents the biasing member attached to the engagement hole from being detached from the engagement hole. It is characterized by
According to this, it is possible to prevent the spring member inserted into the engagement hole from coming off easily from the engagement hole.

[Tenth Aspect]
A tenth aspect is characterized in that, in any one of the first to ninth aspects, the biasing member has a grip portion 86 .
This makes it easier for the operator to handle the biasing member.

[11th aspect]
An eleventh aspect is characterized in that, in the tenth aspect, the outer shape of the grip portion is circular.
According to this, it is easy for the operator to grip the grip portion.

[Twelfth aspect]
A twelfth aspect is a sheet feeding device (e.g., manual sheet feeding device 70, sheet feeding device 4) that feeds sheets held by the sheet holding device, and the sheet holding device is the first to eleventh modes. The sheet holding device according to any one of the above is used.
According to this, it is possible to provide a sheet feeding apparatus having a sheet holding device capable of accurately detecting the rotation angle of the rotating member from the detection result of the rotation position detection means.

[13th aspect]
A thirteenth aspect is an image forming apparatus (for example, a copier 1) having a sheet holding device, characterized in that the sheet holding device according to any one of the first to eleventh aspects is used as the sheet holding device. It is something to do.
According to this, it is possible to provide an image forming apparatus having a sheet holding device capable of accurately detecting the rotation angle of the rotating member from the detection result of the rotation position detection means.

Reference Signs List 1: image forming apparatus 2: image forming apparatus main body 3: image reading apparatus 4: paper feeder 5: automatic document feeder 70: manual feeder 71: opening/closing members 71A, 72B: pivot 72: manual feed tray 72B: Sheet stacking surface 72C: base 73: link members 74A, 74B: side fence 75: guide rails 81A, 81B: rack 82: pinion 83: rotary sensor 83a: rotor 83b: engagement hole 83c: inner wall plane portion 83d: entrance edge Portion 83e: Outlet edge 84: Gear 84a: Rotating shaft 84b: D-cut surface 85, 185: Spring 85a: Tip bent portion 85b: First bent portion 85c: Second bent portion 85d: First straight portion
85e: second straight portion 85f: third straight portion 85f1: fourth straight portion 85f2: fifth straight portion 85f3: third bent portion 85g: connecting portions 86, 186: grip portion 87: overhang portion 88: sensor substrate 89a: Positioning main reference boss 89b: Positioning secondary reference bosses 89c, 89d, 89e, 89f: Flutter suppression bosses

JP 2015-113198 A

Claims (10)

a regulating member movable in a direction to contact and separate from the edge of the sheet;
a rotating member that rotates according to the movement of the regulating member;
a member to be detected that is attached to the rotating member and rotates integrally;
A sheet holding device comprising rotational position detection means for detecting the rotational position of the member to be detected,
The contact portion of the rotating member contacts the contact portion of the member to be detected in the rotation direction of the rotating member, so that the member to be detected rotates integrally with the rotating member. can be,
having a rotation shaft that is a D-cut shaft provided on one of the rotating member and the member to be detected, and an engagement hole that engages with the rotation shaft provided on the other;
One of the abutting portion and the abutted portion is a D-cut surface of the D-cut shaft, and the other is an engaging surface that is an inner wall surface of the engaging hole that engages with the D-cut surface,
a biasing member that applies a biasing force between the rotating member and the detected member to maintain the contact state between the contact portion and the contacted portion ;
The biasing member is mounted inside the engagement hole so as to bias one end side of the D-cut surface in a direction orthogonal to the axial direction of the rotating shaft in a direction away from the engagement surface. A sheet holding device characterized by : The sheet holding device according to claim 1 ,
The sheet holding device, wherein the biasing member is a spring member that applies the biasing force by a restoring force against deformation of the wire. In the sheet holding device according to claim 2 ,
The spring member has one or more bent portions obtained by bending the wire rod, and the biasing force is applied by a restoring force when the bent portions are deformed in the closing direction or the opening direction. sheet holding device. In the sheet holding device according to claim 3 ,
The spring member is attached so that at least one of the bent portions penetrates the engagement hole, and the bent portion is positioned closer to the engagement hole than the engagement hole in a plane direction perpendicular to the axial direction of the rotating shaft. A sheet holding device, characterized in that it is held in a posture positioned on the outside. The sheet holding device according to claim 4 ,
When the spring member is attached, the bent portion is inserted into the engagement hole and the bent portion passes through the engagement hole at the time when the biasing force is generated by the spring member. A sheet holding device characterized by having a shape. The sheet holding device according to any one of claims 1 to 5 ,
A sheet holding device comprising a detachment prevention member that prevents the biasing member attached to the engagement hole from being detached from the engagement hole. The sheet holding device according to any one of claims 1 to 6 ,
The sheet holding device, wherein the biasing member has a grip portion. The sheet holding device according to claim 7 ,
The sheet holding device, wherein the outer shape of the gripping portion is circular. A sheet feeding device for feeding a sheet held by a sheet holding device,
A sheet feeding device using the sheet holding device according to any one of claims 1 to 8 as the sheet holding device. An image forming apparatus including a sheet holding device,
An image forming apparatus using the sheet holding device according to any one of claims 1 to 8 as the sheet holding device.

Images