JP2021155186A - Sheet feeder and image forming apparatus - Google Patents

Abstract

To prevent paper feeding failure such as paper feed delay, a jam or the like caused by curling by detecting a curling state of a sheet.SOLUTION: A sheet feeder 10 comprises a sheet detection part 50 for detecting an upper face of a sheet. The sheet detection part 50 comprises a first detection part 51 for detecting a substantially central part in a width direction X of the sheet crossing in a sheet conveyance direction, and a second detection part 52 for detecting an end portion in the width direction X of the sheet. The second detection part 52 is movably provided in the width direction X according to a width of the stored sheet. Presence/absence of curling and curling shape of the sheet are detected based on detection information of the first detection part 51 and detection information of the second detection part 52 thereof.SELECTED DRAWING: Figure 3

Description

The present invention relates to a sheet feeding device and an image forming apparatus including the sheet feeding device.

The image forming apparatus is provided with an accommodating portion such as a paper cassette or a paper tray for accommodating a plurality of sheets in the sheet supply device. The sheet feeding device includes a feeding member that feeds one sheet at a time toward the sheet transport path in order from the highest sheet among the sheets stored in the accommodating portion.

If the sheet is left loaded in this type of accommodating portion, the sheet may absorb moisture due to the influence of the indoor environment and curl so that both ends of the sheet warp. In particular, when curls occur on thick sheets such as stiff paper and glossy paper, there is a problem that paper feed delays and jams and other paper feed defects are likely to occur.

For example, in Patent Document 1, in order to prevent poor paper feeding due to curling of the sheet, entanglement in the paper ejection roller, etc., a full detection actuator for detecting the full state of the sheet is provided in the width direction of the paper ejection section. A plurality of image forming devices arranged in the above are disclosed. When the full state of the sheet is detected by any one of the plurality of full detection actuators, the image forming operation is temporarily stopped.

Japanese Unexamined Patent Publication No. 2008-230821

The sheet used for image formation usually has various sizes such as A4 size, B4 size, and A3 size. In the image forming apparatus disclosed in Patent Document 1, in order to detect such a plurality of sizes of sheet edges, a full detection actuator is provided at a position 8 mm inward in the width direction from the sheet edges of various sizes. Are arranged to correspond to different sizes. Therefore, it is necessary to provide full detection actuators for each type of seat size, which causes a problem that the device structure is complicated and the cost is increased.

In addition, the curl that occurs on the sheet varies depending on the image formation conditions and the type of sheet, such as a valley curl with a curved edge and a mountain curl with a raised center and a lowered edge. be. Further, even if the sheet fed toward the sheet transport path is curled, it may be possible to feed paper depending on the curl shape. Therefore, it is preferable to detect not only whether or not the sheet is curled, but also the curled shape, and it is possible to determine when the image forming operation does not have to be stopped even if the sheet has curled. Was desired.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to detect the presence or absence of curl of a sheet and the curl shape when the sheet has curl, which is caused by curl. It is an object of the present invention to provide a sheet supply device capable of preventing a paper feed delay, a jam, and other paper feed defects, and an image forming device provided with the sheet supply device.

In order to achieve the above object, the present invention comprises a sheet feeding device including a sheet accommodating portion, a feeding member for pulling out the sheet in the accommodating portion in the sheet transport direction, and a sheet detecting unit for detecting the upper surface of the sheet. The sheet detection unit includes a first detection unit that detects a substantially central portion in the width direction of the sheet intersecting the sheet transport direction, and at least one second detection unit that detects an end portion in the width direction. The second detection unit is provided so as to be movable in the width direction according to the width of the accommodated sheet, and the detection information of the first detection unit and the detection information of the second detection unit can be obtained. Based on this, it is characterized in that the presence or absence of curl and the curl shape of the sheet are detected.

Further, in the sheet supply device having the above configuration, the accommodating portion is provided with a regulation plate that is movable in the width direction and is aligned with the width of the sheet, and the second detection unit is the said. It is preferable that the device is locked to the regulation plate so that it can be moved in the width direction.

Further, the second detection unit includes a detection piece that is movable in the width direction and a sliding shaft that supports the detection piece so as to be movable along the width direction, and the detection piece is in the sheet transport direction. The regulation plate is provided on the downstream side of the above and is rotatable around the axis of the sliding shaft, and the regulation plate is provided with a contact portion for locking to the detection piece and is locked to the contact portion. It is preferable that the detection piece is moved along the sliding shaft together with the regulation plate in the width direction. Further, the detection piece may be urged toward the center side in the width direction by connecting an urging member.

Further, a loading member capable of loading a sheet is provided in the accommodating portion, and the sheet detecting unit is arranged on the downstream side in the sheet transporting direction and facing the end portion of the loading member. Is preferable.

An image forming apparatus including a sheet supply apparatus having the above configuration is also within the scope of the technical idea of the present invention.

By providing the above-mentioned specific items, it is possible to detect the presence or absence of curl of the sheet and the curl shape of the sheet, and it is possible to prevent paper feed delays and paper feed defects such as jams due to such curls. It becomes.

In the present invention, a first detection unit that detects a substantially central portion in the width direction of the sheet and a second detection unit that detects an end portion in the width direction are provided, and the second detection unit is adjusted to the width of the sheet. Since it is configured to be movable in the width direction, it is possible to reduce the cost and efficiently detect the presence or absence of curl with a small number of parts, and it is possible to prevent paper feeding defects and stably feed paper. It becomes.

It is sectional drawing which shows the image forming apparatus which concerns on embodiment of this invention. It is a perspective view which shows the sheet supply apparatus which concerns on embodiment of this invention. It is a perspective view which shows the structure of the sheet detection part in the sheet supply device. It is an enlarged front explanatory view which shows the 2nd detection part in the sheet feeding device, and the upper part of the 1st regulation plate in an enlarged manner. It is a front explanatory view which shows the 2nd detection part and the upper part of the 1st regulation plate in an enlarged manner. It is a perspective view which shows the sheet feeding device as seen from the downstream side in the sheet transporting direction.

A sheet supply device according to an embodiment of the present invention and an image forming device including the sheet supply device will be described with reference to the drawings.

(Image forming device)
FIG. 1 is a cross-sectional explanatory view showing an image forming apparatus 1 according to the present embodiment. The image forming apparatus 1 according to this embodiment forms and outputs an image, for example, a copying machine and a multifunction device having a copying function such as a printer, or a multifunction peripheral device (MFP) including a function other than copying. It is said to be a device.

The image data handled by the image forming apparatus 1 is one corresponding to a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y), or a single color (for example, black) is used. It is supposed to correspond to the monochrome image that was there.

The image forming apparatus 1 includes an optical scanning apparatus 11 in the apparatus main body 1a, and irradiates a photoconductor drum 13 as an image carrier in a charged state with laser light corresponding to image information composed of digital signals to generate static light. Form an electro-latent image. Further, the apparatus main body 1a is provided with four developing apparatus 12, a photoconductor drum 13, a drum cleaning apparatus 14, a charging device 15, and the like in order to form four types of toner images corresponding to each color. The four image stations Pa, Pb, Pc, and Pd are associated with black (K), cyan (C), magenta (M), and yellow (Y), respectively.

In any of the image stations Pa, Pb, Pc, and Pd, after the residual toner on the surface of the photoconductor drum 13 is removed and recovered by the drum cleaning device 14, the surface of the photoconductor drum 13 is made uniform to a predetermined potential by the charger 15. Is charged, and the photoconductor drum 13 is exposed by the optical scanning device 11. Then, the electrostatic latent image formed on the surface of the photoconductor drum 13 is developed by the developing device 12 to form a toner image.

The developing device 12 visualizes the latent image formed on the surface of the photoconductor drum 13 with four color (KCMY) toners. As a result, toner images of each color are formed on the surface of each photoconductor drum 13.

While the intermediate transfer belt 21 orbits, the belt cleaning device 22 removes and recovers the residual toner of the intermediate transfer belt 21, and the toner images of each color on the surface of each photoconductor drum 13 are sequentially transferred to the intermediate transfer belt 21. The toner images are superposed to form a color toner image on the intermediate transfer belt 21.

A nip region is formed between the intermediate transfer belt 21 and the transfer roller 23a of the secondary transfer device 23. The sheet S as a recording medium conveyed through the sheet transfer path 31 is sandwiched in the nip area and conveyed, and the color toner image on the surface of the intermediate transfer belt 21 is transferred to the sheet S. By sandwiching the sheet S between the heating roller 24 of the fixing device 16 and the pressurizing roller 25, heating and pressurizing the sheet S, the color toner image on the sheet S is fixed. The resist sensor 26 detects a test pattern formed on the intermediate transfer belt 21 which is conveyed in the sub-scanning direction as the intermediate transfer belt 21 moves around.

(Sheet supply device)
The sheet supply device 10 is provided below the device main body 1a, includes a paper feed cassette 60 for accommodating the sheet S used for image formation, and feeds the sheets S one by one from the paper feed cassette 60. It is fed to Y and supplied. The sheet S is drawn out from the paper feed cassette 60, is conveyed through the sheet transfer path 31, is conveyed to the output tray 39 via the discharge roller 36 via the secondary transfer device 23 and the fixing device 16. As a result, the image-formed sheet S is discharged to the paper ejection tray 39.

After the sheet S is temporarily stopped in the sheet transfer path 31 and the tips of the sheets S are aligned, the sheet S is transferred in accordance with the transfer timing of the toner image in the nip area between the intermediate transfer belt 21 and the transfer roller 23a. A resist roller 34 for starting the operation, a transfer roller 35 for promoting sheet transfer, and the like are arranged.

In the image forming apparatus 1 according to the present embodiment, the paper feed cassette 60 is provided so as to be able to be taken in and out from the sheet supply device 10. FIG. 2 is a perspective view showing the seat supply device 10, and FIG. 3 is a perspective view showing the configuration of the seat detection unit 50 in the seat supply device 10.

In the figure, the arrow X indicates the mounting direction (pulling direction or inserting direction) of the paper feed cassette 60 with respect to the sheet feeding device 10, and corresponds to the width direction of the sheet S. The arrow Y is a direction orthogonal to the width direction X, and indicates a paper feeding direction (sheet conveying direction) in which the sheet S is sent out from the sheet feeding device 10.

The sheet supply device 10 includes a paper feed cassette 60 as an accommodating portion. A large number of sheets S of any one size selected from sheets of various sizes can be mounted on the paper cassette 60. The upper surface of the paper feed cassette 60 is open, and a loading member 61 capable of loading the sheet S is provided inside the bottom surface.

Further, the paper feed cassette 60 is provided with a first regulation plate 64 and a second regulation plate 65 slidable in the width direction X of the sheet S, and a third regulation plate 66 slidable in the paper feed direction Y. .. The first regulation plate 64 and the second regulation plate 65 regulate the position of the end portion of the sheet S in the width direction (short side direction) X. The third regulating plate 66 regulates the position of the end portion of the sheet S in the long side direction along the paper feeding direction Y. As an example, the paper cassette 60 is provided with a second regulation plate 65 on the front side in the pull-out direction of the paper cassette 60 (lower right direction in the drawing in the width direction X in FIG. 2), and a second regulation plate 65 is provided on the back side. 1 A regulation plate 64 is provided.

As shown in FIG. 1, the loading member 61 can load a large number of sheets S, and an end portion (right end portion in the drawing) on the downstream side in the paper feeding direction Y is provided so as to be able to move up and down. There is. For example, the loading member 61 is rotatably supported by the support member 62 and is a rotating plate that is rotatable about an axis along the width direction X. On the downstream side of the loading member 61, a lift-up member 63 for lifting up the loading member 61, a drive mechanism (not shown) for driving the lift-up member 63, and the like are provided.

One end edge of the lift-up member 63 is rotationally driven by the drive mechanism to rotate about an axis. The other end edge of the lift-up member 63 is in contact with the lower surface of the loading member 61, and the loading member 61 is tilted as it rotates. As a result, in the paper feed cassette 60, the loading member 61 is lifted up with the end on the downstream side in the paper feed direction Y as a free end.

The sheet supply device 10 includes a pickup roller 41 and a vertically paired paper feed roller 42 and a separation member 43 as a feed member for feeding the sheets S in the paper cassette 60 one by one in the paper feed direction Y. Is provided in the main body 10a. The pickup roller 41 is provided in the upper part on the downstream side in the paper feeding direction Y. Further, the paper feed roller 42 is arranged on the upper surface side of the sheet S pulled out by the pickup roller 41, and the separation member (here, the separation roller) 43 is arranged so as to face the paper feed roller 42. As shown in FIG. 2, the main body 10a is provided with these members covered with a closing member.

By tilting the loading member 61, the mounted sheet S is lifted to a position where it can be fed, and is brought into contact with the pickup roller 41. As shown in FIG. 3, the pickup roller 41 is swivelable around the drive shaft 45 of the paper feed roller 42. Further, the pickup roller 41 is rotationally driven in the same direction as the paper feed roller 42 by interposing a transmission belt 44 or a gear between the pickup roller 41 and the paper feed roller 42. As a result, the sheets S placed on the loading member 61 are picked up one by one from the top and sent to the sheet transfer path 31 via the paper feed roller 42, the separation member 43, and the transfer roller 35.

(Sheet detector)
The sheet supply device 10 is provided with a sheet detection unit 50 that detects the upper surface of the sheet (seat bundle) S on the loading member 61. As shown in FIG. 2, the sheet detection unit 50 is arranged so as to be on the downstream side of the paper feeding direction Y and facing the downstream end portion of the loading member 61.

As shown in FIG. 3, the sheet detection unit 50 includes a first detection unit 51 that detects the upper surface of the sheet S at a substantially central portion in the width direction X, and the sheet at one end of the width direction X of the sheet S. It is provided with a second detection unit 52 that detects the upper surface of S. In the exemplary embodiment, the first detection unit 51 is provided adjacent to the pickup roller 41 and the paper feed roller 42.

The first detection unit 51 includes a holder member 512 connected to the roller shaft 411 of the pickup roller 41, a detection flag 511 provided at the tip of the holder member 512 (upstream end in the paper feed direction Y), and the like. It is provided with a first sensor 513 which is a detection means. The first detection unit 51 detects the position (height) of the pickup roller 41.

The detection flag 511 is moved up and down via the holder member 512 as the pickup roller 41 moves up and down. The first sensor 513 is, for example, a photosensor having a light emitting unit and a light receiving unit, and light from the light emitting unit is blocked or transmitted depending on the position (height) of the detection flag 511. The first sensor 513 turns on the output of the detection signal when the light from the light emitting unit is in a light-shielded state, and turns off the output of the detection signal when the light from the light emitting unit is in a transmitted state.

The second detection unit 52 includes a second detection piece 521 that is rotatably supported, a sliding shaft 522 that supports the second detection piece 521 on the main body 10a, and a second sensor 524 that is a detection means. It is provided with a detection flag 525 fixed to the sliding shaft 522. The sliding shaft 522 is arranged along the width direction X and is supported by the main body portion 10a, has a detection flag 525 at one end and a second detection piece 521 at the other end. The sliding shaft 522 holds the detection flag 525 and the second detection piece 521 rotatably around the axis, and is provided with a D-cut surface or an I-cut surface along the axial direction to axis the second detection piece 521. It is slidably supported in the direction.

Like the first sensor 513, the second sensor 524 is a photo sensor having, for example, a light emitting unit and a light receiving unit. When the light from the light emitting unit is in a light-shielded state, the output of the detection signal is turned on and the second sensor 524 is in a transmitted state. In that case, the output of the detection signal is turned off. The second detection piece 521 is provided so as to be movable in the width direction X according to the width of the accommodated sheet S. Therefore, when the second detection piece 521 is located at the end of the uppermost seat S among the seats S loaded on the loading member 61, the second sensor 524 is positioned at the upper surface of the end of the seat S. Height) can be detected.

On the paper cassette 60 side, a first regulation plate 64 that is movable in the width direction X and is aligned with the width of the sheet S is provided. The first regulation plate 64 is slidable along the width direction X, and is set according to the width of the sheet S loaded on the loading member 61.

4A and 4B are front explanatory views showing an enlarged view of the second detection unit 52 and the upper portion of the first regulation plate 64, and FIG. 5 shows a sheet feeding device 10 from which the closing member has been removed in the paper feeding direction Y. It is a perspective view which shows from the downstream side of.

As shown in FIG. 4A, the second detection piece 521 has a substantially L-shaped shape that gradually widens at the substantially center of the front view, and has a downwardly convex contact portion 521a. The upper surface of the sheet S loaded on the loading member 61 comes into contact with the contact portion 521a. As shown in FIG. 3, in the second detection piece 521, the upstream end of the paper feeding direction Y is attached to the sliding shaft 522, and the downstream end is a free end that is rotated around the axis. ..

The second detection piece 521 is provided with a locking portion 523 extending downward. In the exemplary embodiment, the locking portion 523 is arranged on the back side of the second detection piece 521 with the first regulation plate 64 interposed therebetween, and is integrally formed with the second detection piece 521. When the second detection piece 521 is viewed from the front, the locking portion 523 is located between the contact portion 521a and the sliding shaft 522 and extends below the second detection piece 521.

The first regulation plate 64 is provided with a contact portion 642 that can be locked to the locking portion 523 at the upper end portion on the downstream side of the paper feed direction Y corresponding to the second detection piece 521. As shown in FIG. 4A, the contact portion 642 is a protruding portion extending upward from the upper corner portion of the first regulation plate 64. Further, a recess 641 having an ascending inclined surface from the front side to the back side is provided at the upper end portion of the first regulation plate 64.

FIG. 4A shows a state when the first regulation plate 64 is slid along the width direction X. When the first regulation plate 64 slides, the locking portion 523 of the second detection piece 521 locks with the contact portion 642 of the first regulation plate 64. The first regulation plate 64 pushes the second detection piece 521 in the width direction X via the contact portion 642. The second detection piece 521 slides along the sliding shaft 522.

During this time, the support portion 54 provided on the main body portion 10a of the second detection piece 521 is provided so that the second detection piece 521 does not descend due to its own weight and the contact portion 521a and each portion of the paper cassette 60 are not buffered. The base 527 is supported so as to be lifted upward. When the second detection piece 521 is located at the front end of the sliding shaft 522, as shown in FIG. 4A, the second detection piece 521 is lifted to an upper position not buffered by the first regulation plate 64.

When the paper cassette 60 is inserted, the contact portion 642 of the first regulation plate 64 and the locking portion 523 of the second detection piece 521 are locked, and the second detection piece 521 is placed on the first regulation plate 64. By being pushed and sliding, the base portion 527 is separated from the support portion 54. As shown in FIG. 4B, the second detection piece 521 hangs downward in the drawing due to its own weight, is guided by the recess 641 of the first regulation plate 64, and is located on the front side of the first regulation plate 64. Subsequently, by inserting the paper feed cassette 60, the second detection piece 521 is pushed by the first regulation plate 64 and moves to the back side along the width direction X. When the insertion of the paper cassette 60 is completed and the paper cassette 60 is mounted on the main body 10a, the second detection piece 521 is positioned at the end (back end) of the uppermost sheet S in the width direction X. Will be.

As shown in FIG. 4B, the sheet S is raised by tilting the loading member 61 while the paper cassette 60 is mounted on the main body 10a. Since the second detection piece 521 hangs down due to its own weight, the contact portion 521a hits the upper surface of the raised sheet S and is pushed up to rotate. The second detection piece 521 is arranged at a position (height) on the upper surface of the sheet S end portion.

Such rotation of the second detection piece 521 rotates the detection flag 525 via the sliding shaft 522. In the second sensor 524, the light from the light emitting portion is shielded or transmitted by the position of the detection flag 525, and the position of the upper surface at the end portion of the uppermost sheet S loaded on the loading member 61 is detected. When the light from the light emitting unit is blocked and the sheet S is in a position where the sheet S can be fed, the second sensor 524 turns on the output of the detection signal and is in a transmitted state and is not in a position where the sheet S can be fed. The output of the detection signal is turned off.

Further, in the first detection unit 51, the upper surface of the loaded seat S pushes up the pickup roller 41 as the loading member 61 rises, and in conjunction with this, the detection flag 511 is pushed up. In the first sensor 513, the detection flag 511 changes the transmission state to the light-shielding state, and the output of the detection signal changes from OFF to ON.

A control unit (not shown), which is a control means, detects the presence or absence of curl and the curl shape of the sheet S based on the detection information of the first detection unit 51 and the detection information of the second detection unit 52. When the loading member 61 is lifted up after the paper cassette 60 is mounted, the control unit determines whether or not the sheet S loaded on the loading member 61 has risen to a predetermined height at which paper can be fed. , Monitor the detection signal of the sheet detection unit 50.

When the detection signal of the first detection unit 51 is ON and the detection signal of the second detection unit 52 is also ON, it is detected that the sheet S has no curl or the curl amount is very small, and the paper is fed. Judged as possible. The lift-up of the loading member 61 is stopped, the drive shaft 45 of the paper feed roller 42 is driven, and the feeding of the seat S is started.

Even if the detection signal of the first detection unit 51 is ON, when the detection signal of the second detection unit 52 is OFF, it is determined that the sheet S has a curl. In this case, it indicates that the second detection piece 521 of the second detection unit 52 has not risen to a predetermined height, and the end portion of the sheet S is lower than the central portion, that is, the sheet S is in the width direction X. It is detected that the central part is a "mountain curl" that bulges upward. Although the seat S has a curl, the upper surface of the seat S is in contact with the pickup roller 41. Therefore, it is possible to pull out the sheet S, and it is determined that the sheet S can be fed, and the feeding of the sheet S is started.

It is determined that the sheet S has a curl even when the detection signal of the first detection unit 51 is OFF and the detection signal of the second detection unit 52 is ON. In this case, the pickup roller 41 connected to the first detection unit 51 does not abut on the upper surface of the seat S, and the seat S is detected as a "valley curl" in which the central portion in the width direction X bulges downward. In this state, the sheet S cannot be pulled out by the pickup roller 41, and it is determined that paper feeding is not possible.

When the sheet S has a curl shape of "valley curl", an instruction to make the sheet S "mountain curl" is output, for example, the operation panel is displayed to turn the sheet S over, and the paper can be fed. Processing to the state is prompted. Further, a torque limiter 514 may be provided on the drive shaft 45 of the paper feed roller 42, and the pickup roller 41 and the paper feed roller 42 may be rotated to a position (height) where the pickup roller 41 abuts on the sheet S. As a result, even if the sheet S has a "valley curl", the paper can be fed.

As described above, in the sheet supply device 10, the presence or absence of curl of the sheet S is detected by the two sheet detection units 50 of the first detection unit 51 and the second detection unit 52, and if the sheet S has curl, the curl is detected. It is possible to detect the shape as well. Then, by performing the processing according to the curl shape, even if the sheet S is curled, the paper feeding operation can be stably performed, and the occurrence of jam or the like can be prevented.

As shown in FIG. 3, the second detection piece 521 of the second detection piece 521 is provided with an urging member 53. The coil spring as the urging member 53 is arranged along the width direction X, one end is connected to a spring locking portion 526 provided above the second detection piece 521, and the other end is connected to a main body portion 10a (not shown). It is connected. As a result, the second detection piece 521 is urged toward the center side (front side) in the width direction X. When the paper cassette 60 is pulled out from the main body 10a, the first regulation plate 64 and the second detection piece 521 are released from the lock, and the second detection piece 521 is pulled back to the other end of the sliding shaft 522. The upper end surface of the support portion 54 shown in FIG. 4A is an inclined surface having an upward slope toward the front side, and the second detection piece 521 returns to the front side along the sliding shaft 522 while smoothly riding on the support portion 54. ..

Each time the sheet S is fed, the position of the upper surface of the sheet S loaded on the loading member 61 becomes lower. The position where the pickup roller 41 comes into contact with the seat S is also lowered, and the position of the detection flag 511 is also lowered. The detection signal of the first sensor 513 changes from ON (light-shielding state) to OFF (transmission state). In that case, the lift-up member 63 is rotated by the drive mechanism to lift up the loading member 61. Since the loading member 61 is lifted up, the detection signal of the seat detection unit 50 is monitored in the same manner as described above.

The lifting of the loading member 61 is not only carried out by being rotated via a drive mechanism, but may also be configured to be elastically rotated by being provided with an appropriate spring member or the like. Further, the first regulation plate 64 to which the second detection unit 52 is locked may be provided with a detection mechanism for the regulation position of the seat S, and the control unit may use the detection information of the regulation position of the first regulation plate 64 as information. Based on this, the second detection piece 521 may be configured to move in the width direction X. Further, the user is configured to input the regulation position of the first regulation plate 64 (that is, the size of the sheet S loaded on the loading member 61 is input), and the second detection is based on the input information. The piece 521 may be moved in the width direction.

Further, as described above, the second detection piece 521 is not limited to being locked to the first regulation plate 64 so as to be movable, but is provided on the front side of the paper feed cassette 60 and is provided on the second regulation plate 65. It may be configured to be locked and movable so as to detect the position of the front end portion of the seat S.

As described above, the sheet supply device 10 and the image forming apparatus 1 provided with the sheet supply device 10 according to the present embodiment detect the presence or absence of curl of the sheet S, and if it has curl, detect the curl shape. , It is possible to properly feed the paper without causing jams and the like. Further, in order to detect the curl, it is not necessary to provide a large number of detection units corresponding to a plurality of types of sizes of the sheet S, and it is possible to reduce the cost and efficiently detect the curl. Since the second detection unit 52 can move the second detection piece 521 in the width direction X, it can be applied to detect the end portions of sheets S of various sizes with this one detection unit. can.

The technical scope of the present invention is not to be construed solely by the above-described embodiment, but is based on the scope of claims. In addition, the technical scope of the present invention includes all modifications within the meaning and scope equivalent to the claims.

1 Image forming device 10 Sheet supply device 31 Sheet transfer path 35 Transfer roller 41 Pickup roller (feeding member)
42 Paper feed roller (feeding member)
43 Separation member (feeding member)
50 Sheet detection unit 51 1st detection unit 511 Detection flag 512 Holder member 513 1st sensor 52 2nd detection unit 521 2nd detection piece (detection piece)
522 Sliding shaft 523 Locking part 524 Second sensor 525 Detection flag 53 Biasing member 60 Paper feed cassette (accommodation part)
61 Loading member 62 Support member 63 Lift-up member 64 1st regulation plate 641 Recess 642 Contact part 65 2nd regulation plate 66 3rd regulation plate S sheet

Claims (6)

Seat compartment and
A feeding member that pulls out the sheet in the accommodating portion in the sheet transport direction, and
A sheet supply device including a sheet detection unit that detects the upper surface of the sheet.
The sheet detection unit includes a first detection unit that detects a substantially central portion in the width direction of the sheet intersecting the sheet transport direction, and at least one second detection unit that detects an end portion in the width direction. ,
The second detection unit is provided so as to be movable in the width direction according to the width of the accommodated sheet.
A sheet supply device characterized in that the presence or absence of curl and the curl shape of the sheet are detected based on the detection information of the first detection unit and the detection information of the second detection unit. In the sheet supply device according to claim 1,
The accommodating portion is provided with a regulating plate that is movable in the width direction and is aligned with the width of the sheet.
The second detection unit is a sheet supply device characterized in that it is locked to the regulation plate and is movable in the width direction. In the sheet supply device according to claim 2,
The second detection unit includes a detection piece that can move in the width direction and a sliding shaft that supports the detection piece so that it can move along the width direction, and the detection piece is downstream in the sheet transport direction. It is arranged on the side and is rotatable around the axis of the sliding shaft.
The regulation plate includes a contact portion that locks to the detection piece, and the detection piece locked to the contact portion moves along the sliding shaft together with the regulation plate in the width direction. A seat supply device characterized by. In the sheet supply device according to claim 3,
The detection piece is a sheet supply device to which an urging member is connected and urged toward the center side in the width direction. In the sheet supply device according to any one of claims 1 to 4.
A loading member capable of loading a seat is provided in the accommodating portion.
The sheet supply device is characterized in that the sheet detection unit is arranged on the downstream side in the sheet transport direction and faces the end portion of the loading member. An image forming apparatus comprising the sheet feeding apparatus according to any one of claims 1 to 5.

Images