JP3387695B2 - Sheet feeding apparatus and image forming apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a copying machine, printer, facsimile machine or the like image forming apparatus, and that option cassette
In the sheet storage unit such as a feeding cassette feeders in the sheet feeding apparatus for feeding a sheet one addressed, the pickup roller and the sheet separating roller pair and had a pair of conveying rollers Shi
The present invention relates to a configuration of a sheet feeding device .

[0002]

BACKGROUND OF THE INVENTION Image forming apparatuses such as copying machines, printers and facsimiles, sheet feeding apparatus for the stacked sheets separated one by one to feed to the image forming section is provided.

Recently, as this sheet feeding device , a retard type sheet feeding device having a high sheet separation performance has been widely adopted.

[0004] The sheet feeding apparatus of retard system, Sea
As a separating unit for the sheet, the fed sheet that rotates the fed sheet in the conveying direction and the feed roller that rotates when the torque in the sheet conveying direction of a predetermined value or more act together, and the sheet that is fed by the action of the torque of the predetermined value or less is used. A sheet feeding apparatus using a sheet separation roller pair including a retard roller that rotates in the reverse direction.

As a conventional example, FIG. 12 shows a color laser beam printer (LBP) body equipped with a retard type sheet feeding device , and an optional cover installed below the body.
The set feeder is shown.

As shown in FIG. 12, in an image forming apparatus such as a color LBP, a sheet path from a sheet storing portion (cassette) to a sheet discharging portion is bent in order to reduce a substantial installation area of the apparatus. There are many apparatus configurations in the U-shaped type or the S-shaped type.

In FIG. 12, the main body paper feed cassette 4 is arranged under the projection of the developing means 31 and the transfer drum 32, and the whole thereof is inserted and stored in the main body of the apparatus.

The optional paper feed cassette 4a of the optional cassette feeder 200 additionally installed in the lower part of the image forming apparatus main body 100 is also inserted and stored in the optional cassette feeder 200 as in the main body side.

Further, the feeding device 33 includes a main body sheet feeding cassette 4
The image fixing device 8 is disposed on the right side of the transfer drum 32 (near the downstream side in the transport direction of the recording paper P), and is installed on the projection of the feeding device 33.

[0010] In this device, the sheet path has become a type associated therewith is S-shaped type and U-type,
The substantial installation area is considerably reduced, and the overall size of the device is reduced.

In FIG. 12, the recording paper P separated and sent out from the main body paper feed cassette 4 by the cassette claw 11 and the half-moon paper feed roller 5 is a feed roller 25 and a retard roller 27.
The separation roller pair surely separates and feeds the sheets one by one (with respect to the recording paper that has been double-fed due to defective separation of the claws), is reversed by the conveyance guides 18 and 19, and reaches the registration roller pair 6 by the conveyance roller 28 and the idler roller 29. To do. A gripper 32f is provided at a predetermined position on the outer circumference of the transfer drum 32, and after the skew feeding is performed by the registration roller pair 6,
The front end of the recording paper P fed at a predetermined timing and speed is gripped.

Further, an electrostatic attraction roller 32g is provided on the outer periphery of the transfer drum 32 so as to be able to come into contact with and separate from the transfer drum 32, and the recording paper P is sandwiched between the electrostatic attraction roller 32g and the transfer drum 32 so that the transfer drum 32 is held. By applying pressure to the outer periphery of the recording sheet P and applying a voltage between the electrostatic attraction roller 32g and the transfer drum 32, an electric charge is induced in the recording paper P which is a dielectric and the dielectric layer 32d of the transfer drum 32 to record. The paper P is configured to be electrostatically attracted to the outer periphery of the transfer drum 32.

The method of attracting the recording paper P to the transfer drum 32 is not limited to the electrostatic attraction but may be a suction method using air.

Further, in synchronization with the rotation of the transfer drum 32, the photosensitive drum 2a as an image carrier is rotated in the direction of the arrow in the figure, and the surface of the photosensitive drum 2a is made uniform with respect to the photosensitive drum 2a by the charging means 2b. While being charged, the scanner unit 1 irradiates a magenta image with light to form a magenta latent image on the photosensitive drum 2a.

[0015] The latent image formation and the magenta developing means at the same time
The developing cartridge 31M is driven, and magenta developing is performed by applying a voltage of substantially the same potential as the charging polarity of the photosensitive drum 2a so that magenta toner adheres to the latent image on the photosensitive drum 2a. A voltage having a polarity opposite to that of the magenta toner is applied to the drum 32 to transfer the magenta toner onto the recording paper P on the transfer drum 32 on the photosensitive drum 2a.

When the transfer of the magenta toner is completed as described above, the next developing device is rotationally moved and positioned at a position facing the photosensitive drum 2a, and latent images of cyan, yellow, and black are formed in the same manner as magenta. Then, toner transfer is sequentially performed to form a color image on the recording paper P (during this, the transfer drum 32 rotates four times).

After the image formation, the recording paper P is transferred to the transfer drum 32 by releasing the gripper 32f and operating the separating claw 30.
The image is peeled off and conveyed to the image fixing device 8 (the conveying direction is reversed). After the toner is fixed by the image fixing device 8, it is reversed conveyed by the conveying guides 21 and 22 and the sheet discharging roller pair 9 conveys the image to the top of the apparatus. The sheet is discharged to the face-down tray 10 using the plate.

The recording paper P loaded on the multi-tray 15 is opened, and the multi-paper feed roller 16 of the duplo system is used.
Then, the sheets are separated and fed one by one, reach the registration roller pair 6 by the conveying roller 28 and the idler roller 29, and are conveyed in the same manner as the cassette sheet feeding.

On the other hand, the recording paper P separated and sent from the optional paper feed cassette 4a by the cassette claw 11a and the half-moon paper feed roller 5a is surely separated and fed one by one by the separation roller pair of the feed roller 25a and the retard roller 27a. (Regarding the recording papers that have been fed due to a defective separation of the nails), along with the conveyance guides 12a and 12b, the conveyance roller 7 and the optional
It is transported to the roller pair of the transport roller 3.

Further, the recording paper P is optional with the conveying roller 7.
By the transport roller 3, the transport roller 28 is passed along the transport guides 14 and 17 provided on the main body feeding device 33 through the expansion path 13 provided at the bottom of the image forming apparatus main body 100.
Then, the roller pair of the idler roller 29 is reached, and thereafter the sheet is conveyed in the same manner as the main body cassette sheet feeding.

In such an apparatus, the drum cartridge 2 and each of the magenta, cyan, yellow, and black developing cartridges 31M, 31C, 31Y, and 31Bk can be attached and detached in a direction (front side in the drawing) perpendicular to the conveying direction of the recording paper P. Has become.

Further, as shown in FIG. 14, when the paper jam in the feeding device 33 is pulled out, the main body paper feeding cassette 4 is pulled out, or the multi-paper feeding unit 33a is rotated around the fulcrum shaft 20 and opened to take a treatment. You can do it.

A paper jam on the upper part of the transfer drum (near the separation claw) can be dealt with from a part of the top plate of the apparatus opened.

Further, with respect to a paper jam near the image fixing device 8, the rear cover 26 is opened so that it can be dealt with from here.

The further framework body configuration in the mold steel at a relatively large imaging equipment such as a color copying machine, a paper jam of Parts entire door front side of the apparatus (drawing near side) is the front open It can be treated.

Further, the transfer drum and the like can be slid particularly toward the front side of the apparatus (front side in the drawing), which facilitates treatment.

[0027] Figure 13 and 14 is an enlarged view of the feeding device of the conventional example, FIG. 13 is the main feeding cassette 4 and options
Down feeding cassette 4a and also shows the fully housed a feedable state, FIG. 14 is a state where the multi-feeding unit 33a is opened, the optional paper feed cassette 4a has retard pressure pulled is pressure releasing lever 37a It shows the released state.

The main body sheet feeding cassette 4 in the above-mentioned conventional embodiment is the cassette rail 2 from the front side of the apparatus (front side in the drawing).
It is designed to be attached and detached along the lines 3 and 24, as shown in FIG.
As shown in FIGS. 3 and 14, when the main body sheet feeding cassette 4 is attached or detached, the cam portion 36 on the apparatus front side of the R lower guide 34 provided with the retard roller 27 on the cassette side surface outer shape 41 is pushed down around the rotating shaft 35, The structure is such that the retard roller pressure applied by the tension springs 40 provided at both ends of the R lower guide 34 outside the sheet passing range is released.

Further, when the main body sheet feeding cassette 4 is pulled out, if the handle (not shown) on the front side of the cassette is pulled, the pressure release lever 37 is pushed down diagonally and slid to the right side (the direction of the arrow in the drawing) of the drawing, and its tip end. The cam portion 36 of the R lower guide 34 is pushed down around the rotary shaft 35 to release the retard roller pressure, and is directly connected to the cassette side surface outer shape 41 described above.

When the main body sheet feeding cassette 4 is completely attached, the cassette side surface outer shape 41 is the cam portion 3 of the R lower guide 34.
6, the cam portion 36 pushes the pressure release lever 37 to the left in the drawing so that the retard roller pressure is applied to the feed roller 25 (the pressure release lever has only the horizontal component of its own weight). The cam portion 36 is pushed with a light force.)

With the main body sheet feeding cassette 4 completely mounted, the lever 42 is lifted upward by the cam groove provided in the cassette rail 23, the lifter 38 is lifted by the tension spring 43, and the cassette middle plate 39 is lifted. The structure is such that the paper feed pressure is applied to the.

The feeding device section of the optional cassette feeder 200 has the same structure as the main body feeding apparatus section, and the optional feeding roller 3 is pressed by the feeding roller 7 by the compression spring 44, as shown in FIG. Has a constant width and is evenly arranged at two or more locations in the paper width direction.

[0033]

In the retard type sheet feeding apparatus having the paper path shown in the above-mentioned embodiment, the recording sheet fed from the main body sheet feeding cassette 4 and the optional sheet feeding cassette 4a. If the paper P causes a jam in the feeder of the main body or the optional cassette feeder,
As shown in FIG. 14, it is necessary to open the multi-paper feeding unit 33a or pull out each cassette to perform the jam processing.

At this time, particularly in the jam in the option cassette feeder, the recording paper P is sandwiched between the separating roller pair and the conveying roller pair, and it is necessary to open the multi-feeding unit 33a and perform the jam processing from the upper portion. It was difficult. When the optional paper feed cassette 4a is pulled out, the recording paper P
There was a problem that would be torn.

Further, the image forming apparatus main body 100 may be removed at the time of replacement of the feed roller 25a and the retard roller 27a of the option cassette feeder due to their service life.
It is very difficult to pull out the optional paper feed cassette 4a and insert a hand from the bottom surface, and it is generally a service person compatible.

On the side of the main body of the image forming apparatus, the service person replaces the feed roller and the retard roller by pulling out or removing the feeding apparatus 33 from the main body, which requires a great deal of labor.

On the other hand, the recording paper P conveyed from the conveying roller 7 of the option cassette feeder 200 and the roller pair of the optional conveying roller 3 is conveyed toward the expansion path 13 at the bottom of the image forming apparatus main body 100. If the leading edge of the recording paper P is wavy in a hot and humid environment, the leading edge may not be properly inserted into the hole of the expansion path 13 and a jam may occur.

The present invention has been made to solve the above-mentioned problems of the prior art, and its object is to feed a sheet stacking means and sheets stacked on the sheet stacking means. A feeding unit, and a feeding unit that applies a force in the sheet feeding direction to the sheet fed from the feeding unit,
In a sheet feeding device provided with a separating means that is in contact with the conveying means and applies a force in a direction opposite to the sheet conveying direction to a sheet fed from the feeding means, the separating means is provided with the conveying means. By providing the device so as to be detachable from the contact position, it is possible to facilitate jam processing and exchange of the separating means and the conveying means.

The sheet feeding apparatus has a separating / feeding unit rotatably supported by a shaft, and the separating unit is provided in the separating / feeding unit, so that a jam is removed from the upper portion of the sheet feeding apparatus. And to facilitate the exchange of the separating means and the conveying means.

By providing the first contact pressure releasing means for releasing the contact pressure of the separating means to the conveying means in conjunction with the rotation operation of the separating / feeding unit, damage due to friction between the separating means and the conveying means is prevented. To prevent.

Secondly, the sheet stacking means is detachably mounted in the direction perpendicular to the sheet conveying direction, and the contact pressure of the separating means to the conveying means is released in association with the attaching / detaching operation of the sheet stacking means.
The contact pressure releasing means is provided to prevent the sheets from being torn when the sheet stacking means is pulled out.

Separation means consisting of a conveyance means and a first drive transmission means for transmitting power to the conveyance means, a separation means composed of the separation means and a second drive transmission means for transmitting power to the separation means. By providing the support part and the sheet feeding device main body in a detachable manner, it is possible to easily remove the conveying means and the separating means, so that even a general user can easily replace them.

There is provided an exterior cover which rotates around an axis provided outside the rotation center of the separating / feeding unit, and the separating / feeding unit is engaged with the main body of the sheet feeding apparatus. By providing an engaging member to be fixed and interlocking means for engaging and disengaging the engaging member in conjunction with the rotation operation of the outer cover, it is possible to easily perform jam processing and conveyance simply by opening the outer cover. The purpose is to allow a general user to easily exchange the means and the separating means. Further, the separate feeding unit can be fixed only by closing the outer cover.

By providing a connecting member for connecting the exterior cover and the main body of the sheet feeding device, and the connecting member also serves as a damper and an interlock switch rod, an interlock switch mechanism is provided with a simpler structure. It is to be able to ease the opening / closing operation of the exterior cover.

By providing the sheet feeding device and the image forming means for forming an image on the sheet fed by the sheet feeding device, the jam processing is easy and the separating means and the conveying means are easily exchanged. Image forming apparatus.

By providing the sheet feeding device,
An object of the present invention is to provide an optional cassette feeder in which jam processing is easy and replacement of the separating means and the conveying means is easy.

By providing a conveying rotary member pair for sandwiching and feeding the sheet into the image forming apparatus, and having at least one of the conveying rotary member pairs having a width equal to the width of the conveyed sheet, the corrugation of the sheet is performed. It is to suppress the rampage and enable smooth sheet conveyance. To provide an option cassette feeder excellent in assemblability by having a structural frame body for accommodating the sheet feeding device and by providing a fixing means for positioning and fixing the sheet feeding device from the upper part of the structural frame body. is there.

[0048]

In order to achieve the above object, in the present invention, a sheet stacking means, a feeding means for feeding a sheet stacked on the sheet stacking means, and the feeding means. conveying means for imparting a sheet conveying force to the sheet fed from the separation means for applying the sheet conveying direction opposite to the direction of the force to the sheet fed from the feeding means in contact with the conveying means With the shaft provided on the device side
Rotate to the center to separate the separating means from the contact position with the conveying means.
And the separation feeding unit that is detachable from the separation feeding unit during rotation of the separation feeding unit.
It is configured to be rotatable around an axis provided outside the heart
The external cover and the separate feeding section
A lock lever that engages with a pin on the body side and fixes the separation feeding unit.
Provided between the bar and the separate feeding unit and the exterior cover
When the outer cover is opened, the separation feeding unit is
The pulling link for opening, the separate feeding section and the outer
Provided between the outer cover and the outer cover,
And a push link for closing the separation feeding unit , the pull link being connected to the lock lever.
The lock lever when opening the exterior cover.
The lock of the pull link and the push
The pins are attached to the separate feeding section with pins and slots.
And when the pulling link opens the separation feed.
The push link side, the pin slides in the long hole,
When the push link closes the separation feeding unit,
The feature is that the pin slides in the long hole on the tension link side .

[0049]

It is characterized by further comprising first contact pressure releasing means for releasing the contact pressure of the separating means with respect to the conveying means in conjunction with the rotation operation of the separating and feeding section.

The sheet stacking means is removably mounted in the direction perpendicular to the sheet conveying direction, and the second contact pressure for releasing the contact pressure of the separating means to the conveying means in association with the attaching / detaching operation of the sheet stacking means. It is characterized in that a release means is provided.

Separation of the conveying means supporting portion including the conveying means and the first drive transmitting means for transmitting the power to the conveying means, and the separating means including the separating means and the second drive transmitting means for transmitting the power to the separating means. A means supporting portion is detachably attached to the main body of the sheet feeding apparatus.

[0053]

It is characterized in that it has a connecting member for connecting the exterior cover and the main body of the sheet feeding apparatus, and the connecting member also serves as a damper and an interlock switch rod.

An image forming apparatus comprising a sheet feeding device and image forming means for forming an image on a sheet fed by the sheet feeding device.

An optional cassette feeder for the image forming apparatus, which is equipped with a sheet feeding device.

It is characterized in that a conveying rotary member pair for sandwiching and feeding the sheet into the image forming apparatus is provided, and at least one of the conveying rotary member pairs has a width equal to a sheet width to be conveyed. It is an optional cassette feeder .

An option having a structural frame body for accommodating the sheet feeding device, and a fixing means for positioning and fixing the sheet feeding device from the upper part of the structural frame body.
It is a cassette feeder .

[0059]

In the present invention having the above structure, the sheet stacking means, the feeding means for feeding the sheets stacked on the sheet stacking means, and the sheet conveying direction for the sheets fed from the feeding means. In the sheet feeding device, the sheet feeding device is provided with a feeding unit that applies a force of, and a separating unit that is in contact with the feeding unit and that applies a force in a direction opposite to the sheet feeding direction to the sheet fed from the feeding unit. When opening the outer cover, pull
The tension link unlocks the lock lever.
By opening the separate feeding unit, the separating unit can be separated from the contact position with the conveying unit.

The separation feeding unit provided with the separation means is
It rotates around an axis provided in the sheet feeding device.

The contact pressure of the separating means with respect to the conveying means is released by the first contact pressure releasing means in conjunction with the rotation operation of the separating / feeding unit.

The sheet stacking means can be attached / detached in a direction perpendicular to the sheet conveying direction, and the contact pressure of the separating means on the conveying means is released by the second contact pressure releasing means in association with the attaching / detaching operation of the sheet stacking means. It

Separation of the conveying means supporting portion including the conveying means and the first drive transmitting means for transmitting the power to the conveying means, and the second driving transmission means for transmitting the power to the separating means and the separating means. The means supporting portion can be attached to and detached from the main body of the sheet feeding device.

[0064]

The connecting member connecting the outer cover and the main body of the sheet feeding device can alleviate sudden movement of the outer cover or push the interlock switch.

[0066] By providing the sheet feeding apparatus and an image forming unit, sea fed by the said sheet feeding apparatus
To form an image on a door.

The sheet feeding device is an optional cassette
Optional cassette fee by preparing for the feeder
Sheet feeding from Da .

[0068] options by conveying rotating body pairs at least one of the conveying rotating body pair having a width equivalent to the sheet width to be conveyed
The sheet is pinched from the cassette cassette feeder and fed into the image forming apparatus.

By the fixing means, the sheet feeding device is positioned and fixed from the upper part of the structural frame body for accommodating the sheet feeding device.

[0070]

1 is a perspective view of an option cassette feeder 200 embodying the present invention.

FIG. 2 is a sectional view of a paper path portion of an optional cassette feeder 200 having a sheet feeding device using the separation roller pair method embodying the present invention.

[0072] Figure 3 is separating and feeding portion serving times to which the present invention
The cross-sectional view of the opening / closing mechanism that opens and closes the transfer device 75 by opening and closing the exterior cover 51 is shown.

FIG. 4 shows the rotary feeding device of the sheet feeding device.
Shows a view of the location 75 from paper feeding direction downstream side, Fig 5 is fixed
The figure which looked at the sheet feeding device 45 from the upstream side in the sheet passing direction is shown.

6 to 8 show the opening / closing operation state of the rotary feeding device 75.

The constituent members and parts common to those in the above-mentioned conventional embodiment are designated by the same reference numerals, and their repetitive description will be omitted.

In FIG. 1, the sheet feeding device has a fixed feeding device 45 having a feeding top plate 57, a feeding right side plate 60, and a feeding left side plate 76 as constituent frames, and an opening / closing plate 50 as a constituent frame. It consists rotary feeder 75 which is positioned and fixed to the structural frame unit of optional cassette feeder.

The optional paper feed cassette 4a is attached and detached from the direction perpendicular to the recording paper conveyance direction, and the rotary feeding device 75 can be opened and closed in the recording paper conveyance direction.

The open / close plate 50 of the rotary feeding device 75 is fixedly fed.
The right side plate 60 and the left side plate 76 , which form the device 45, are supported and rotatably mounted around the rotary shaft 53.

In FIG. 2, the half-month paper feeding roller 5a as the feeding means, the feed roller 25a as the feeding means, and the feeding roller 7 are provided on the fixed feeding device 45 side, and the retard roller 27a as the separating means and the optional feeding are provided. roller 3 is rotated
It is provided on the feeding device 75 side. Here, the transport roller 7 and the optional transport roller 3 form a transport rotator pair.

In FIG. 5, the feed roller 25a, together with the one-way clutch 79 and the drive transmission gear 80, constitutes a feed roller unit 56 which is supported by a feed roller support base 78 by a shaft 81 and which is a conveyance means support portion.
Here, the one-way clutch 79, the drive transmission gear 80,
The shaft 81 constitutes a first drive transmission means.

Further, as shown in FIG. 2, the feed roller unit 56 is pushed into the drive shaft 59 by the patchon fastening claws 58, positioned by the positioning pin 77 on the sheet feeding top plate 57, and fastened and fixed by the screws 55.

As a result, the driving force in the paper feeding direction to the feed roller 25a is transmitted from the drive gear 82 provided on the drive shaft 59 to the drive transmission gear 8 of the feed roller unit 56.
Transmitted to 0.

In addition, a cassette is provided on the fixed feeding device 45 side.
As shown in FIG. 1, the conveyance roller 7 guides the recording paper P picked up by the claw 11a and the half-moon feeding roller 5a and reliably separated and conveyed one by one by the separation roller pair to the expansion path 13 below the main body of the image forming apparatus. The sheet feeding drive unit 83 transmits the driving force, which is almost equal to the recording sheet width.

On the other hand, the retard roller 27a, together with the torque limiter 84, constitutes a retard roller unit 49 which is supported by a drive shaft 86 on a retard roller support base 85 as a separating means support portion, as shown in FIG. Here, the torque limiter 84 and the drive shaft 86 constitute second drive transmission means.

The retard roller unit 49 is fixed by a screw 48 positioned by the positioning pins 91 and 92 at the center of the R lower guide 34a.

Accordingly, the retard roller unit 49 becomes swingable with respect to the opening / closing plate 50 around the rotation shaft 35a together with the R lower guide 34a, and the retard roller 27a is brought into pressure contact with the feed roller 25a by the tension spring 40a. (For the swingable range of the R lower guide 34a, the R lower guide 34a is attached to the stopper 47a of the transport lower guide 47.
It is regulated that the rib of hits. ).

Further, a split pin 87 is driven into the drive shaft 86 of the retard roller unit 49, and the joint 8
It is inserted in the U groove of No. 8.

Thus, even if the retard roller unit 49 swings, the driving force is reliably transmitted from the joint 88 via the driving gear 90 and the driving shaft 89.

In addition, a lower conveyance guide 47 is fixed to the open / close plate 50 with screws, and a lower conveyance guide 47 is provided with a conveyance roller holder 46 which is swingable about a shaft 46a.

Further, the transport roller holder 46 is optional.
The transport roller 3 is rotatably provided, and the compression spring 44 is provided between the transport roller 3 and the lower transport guide 47 substantially parallel to the transport direction.

As a result, the optional transport roller 3 is pressed by the transport roller 7, and the swingable range of the transport roller holder 46 is restricted by the stopper 47b of the lower transport guide 47 and the lock lever shaft 54.

In FIG. 3, the fixed feeding device 45 and the rotary feeding are shown.
The feeding device including the device 75 is positioned and fixed to the frame 93 of the optional cassette feeder.

A rotary shaft 52a of the exterior cover 51 is provided outside the rotary shaft 53 of the rotary feeding device 75 at a position close to the exterior surface, and the exterior cover 51 is rotatably attached to the frame 93 of the optional cassette feeder by a hinge 52. Has been.

An elongated hole 69 and a lock lever 65 are rotatably provided around the lock lever shaft 54 on both side surfaces of the opening / closing plate 50, and an oblique groove 65 of the lock lever 65 as an engaging means.
b is inserted into the fixed lock pin 71 provided on the left and right sheet feeding side plates by the force of the tension spring 66.

The oblique groove 65b of the lock lever 65 is designed to bite in the opening direction of the opening / closing plate 50 with respect to the rotating shaft 53.

Further, the rotatable range of the lock lever 65 is restricted by a stopper portion 67 cut and raised from the opening / closing plate 50.

Further, a pulling link 62 as an interlocking device is provided between the pin 72 of the lock lever 65, the exterior cover 51 and the rotating shaft 64, and the pin 72 is slidable in the elongated hole 70 of the pulling link 62. The rotating shaft 64 is only rotatable.

On the other hand, a push link 61 is fitted between the elongated holes 69 provided on both side surfaces of the opening / closing plate 50 and the rotary shaft 63 of the exterior cover 51, and the pin 68 of the push link 61 has the elongated hole 6 formed therein.
9 is slidable, and the rotary shaft 63 is only rotatable.

Also, in FIG. 3 and FIG. 4, the R lower guide 34
Like the conventional embodiment, the cassette insertion opening side of a has a cam portion 36a for releasing the retard roller pressure by pushing down the R lower guide 34a when the cassette is attached and detached, and a cam portion 74 smoothly connected to this cam portion. have. Here, the cam portion 36a and the cam portion 74 constitute second contact pressure releasing means.

6 to 8 are views showing the opened / closed state of the rotary feeding device 75.

When the exterior cover 51 is rotated to the state shown in FIG. 6 from the feedable state shown in FIG.
Pulls the pin 72 of the lock lever 65, the lock lever 65 rotates around the lock lever shaft 54, and the oblique groove 65b of the lock lever 65 is disengaged from the fixed lock pin 71.

At this time, the pin 68 of the push link 61 has the elongated hole 6
Just slide 9.

After that, the rotary feeding device 75 is pulled by the pulling link 62 via the pin 72, and further the action by the returning force of the pulling spring 66 of the lock lever 65, and further by its own weight, is brought to the state shown in FIG. It will rotate.

In the rotary feeding device 75, the left end of the elongated hole 69 hits the pin 68 of the push link 61 and opens in accordance with the rotation of the exterior cover 51.

At this time, the lock lever 65 is the stopper 67.
The pin 72 of the lock lever 65 slides through the elongated hole 70 of the pulling link 62 until it hits.

On the other hand, the cam portion 74 of the R lower guide 34a is rotated.
Immediately after the transfer feeding device 75 starts to open, the fixed feeding device 45
The R lower guide 34a is pressed down by the pressure release roller 73 provided on the paper feed left side plate 76, and the R lower guide 34a is pushed down around the rotation shaft 35a.

That is, the retard roller unit 49 is pushed down to release the retard roller pressure. Here, the pressure release roller 73 constitutes a first contact pressure release means.

While the cam portion 74 of the R lower guide 34a and the cam portion 36a connected thereto are in contact with the pressure releasing roller 73, R
The lower guide 34a is pushed down, and then the R lower guide 3
The rib 4a returns until it hits the stopper 47a of the lower conveyance guide 47.

On the other hand, since the cam portion 36a disappears, the pressure release lever 37a is pushed rightward by its own weight.

Finally, the rotary feeding device 75 and the outer cover 5
1 is opened until the opening / closing plate 50 hits the stopper 94 as shown in FIG.

In the state of FIG. 8, the nip between the separating roller pair and the conveying roller pair is completely opened, and the jam processing from the recording paper conveying direction can be performed very easily.

Further, the retard roller unit 49 is exposed to the outside of the apparatus, and the screw 8 is removed to make the joint 8
It can be easily removed from 8 and can be easily replaced by general users.

Also in the feed roller unit 56, the screw 55 is removed, and the patch of the feed roller support base 78 is patched.
It can be easily removed by pulling out the retaining claw 58,
Even general users can easily replace it.

Further, when removing the screw 55, a cutout portion 7a is provided in the central portion of the conveying roller 7 so that a driver can easily enter it (FIG. 1).

The operation of closing the rotary feeding device 75 is such that when the outer cover 51 is closed from the state shown in FIG.
Pin 68 rotates by pushing the left end of slot 69 of opening / closing plate 50
The feeding device 75 is closed.

On the other hand, the pin 72 of the lock lever 65 slides in the elongated hole 70 of the pulling link 62.

[0117] and, of times that has been closed is pushed by the pin 68
The cam portion 36a of the R lower guide 34a attached to the transfer feeding device 75 is pushed down by the pressure release roller 73 provided on the left side sheet feed plate 76 of the fixed feeding device 45, and further the cam portion 74 connected to the cam portion 36a. Thus, the rotary feeding device 75 is continuously pushed until just before it is completely closed.

[0118] Since this makes it form the cam portion 36a of the R lower guide is coming press from the right direction rather than come to the down from the top of the pressure-releasing lever 37a, it has been pushed to the right cam portion 36a by its own weight It does not ride on the pressure release lever 37a.

Further, since the retard roller pressure is not applied until the moment of contact, the retard roller 27a and the feed roller 25a do not rub against each other.

In FIG. 7, the pin 68 of the push link 61 is shown.
The taper portion 65a of the lock lever 65 provided on the rotary feeding device 75 that has been pushed and closed by means of the fixed lock pin 71 provided on the right side sheet feeding plate 60 and the left side sheet feeding plate 76 of the fixed sheet feeding unit 45. It is pushed down by
When the state is reached, the tension lever 66 returns the lock lever 65, and the pin 72 of the lock lever 65 pulls the pull link 62 and pulls the exterior cover 51, thereby returning to the completely closed state of FIG.

Further, as shown in FIG. 10, the outer cover 5
1 is provided with a link 98, which is linked with a switch rod 95 as a connecting member by a pin 97.

The switch rod 95 is supported by pins 102 and 103 in oblong holes 99 and 101, respectively, and slides horizontally.

In FIG. 10, the solid line shows the outer cover 51 completely open, and the two-dot chain line shows the outer cover 51 completely closed.

As shown in FIG. 10, when the outer cover 51 is completely closed, the interlock switch 105 is pushed on the left side of the switch rod 95.
When 1 starts to open, the interlock switch 105 is released.

On the other hand, the pin 97 of the link 98 has the shaft 52a.
According to the opened / closed state of the outer cover 51 which rotates around the center, the slot 96 of the switch rod 95 is slid vertically as opposed to the switch rod 95 which slides horizontally.

On the other hand, as the outer cover 51 opens,
Since the weight of the rotary feeding device 75 is added, it becomes heavier.
A damper spring 104 is provided.

The damper spring 104 is provided on the exterior cover 51.
Also plays a role of keeping the closed state.

Further, as shown in FIG. 11, the fixed feeding device 4
5 and the rotary feeding device 75 are unitized as a feeding device and can be attached from the upper part of the structural frame (frame) of the optional cassette feeder, and the positioning hole 106 and the screw hole positioned by the positioning pin of the frame. It is fixed with screws at 107. Here, positioning hole 1
06, the screw hole 107 constitutes a fixing means.

The hinge 52 may be provided on the fixed feeding device 45 side, and the opening / closing cover 51 may be added to the feeding device unit.

[0130]

The present invention has the above-described structure and operation, and has sheet stacking means, sheet feeding means for feeding the sheets stacked on the sheet stacking means, and sheet feeding means. A sheet including a conveying unit that applies a force in the sheet conveying direction to the sheet, and a separating unit that contacts the conveying unit and applies a force in a direction opposite to the sheet conveying direction to the sheet fed from the feeding unit Open the exterior cover of the feeder.
When pulling the lock lever,
By opening the separating and feeding portion while releasing the click, thereby disengaging the said separating means from the contact position between the conveying means
You can Therefore, as the outer cover is opened and closed,
It is possible to open and close the separating and feeding section easily and surely, and it is possible to facilitate jam processing and exchange of the separating means and the conveying means.

The sheet feeding device has a separating / feeding unit rotatably supported by a shaft, and the separating unit is provided in the separating / feeding unit, so that the jam from the upper portion of the sheet feeding device is provided. It is possible to easily exchange the processing and separating means and the conveying means.

Since the first contact pressure releasing means for releasing the contact pressure of the separating means to the conveying means is provided in association with the rotating operation of the separating / feeding section, the damage due to the friction between the separating means and the conveying means. Can be prevented.

Secondly, the sheet stacking means is detachably mounted in the direction perpendicular to the sheet conveying direction, and the contact pressure of the separating means to the conveying means is released in association with the attaching / detaching operation of the sheet stacking means.
By providing the contact pressure releasing means, it is possible to prevent the sheets from being torn when the sheet stacking means is pulled out.

Separation means composed of a conveyance means supporting portion made up of conveyance means and first drive transmission means for transmitting power to the conveyance means, and separation means and second drive transmission means for transmitting power to the separation means. By providing the support portion to the main body of the sheet feeding device in a detachable manner, the conveying means and the separating means can be easily removed, and a general user can easily replace them.

[0135]

By having a connecting member for connecting the exterior cover and the main body of the sheet feeding device, and the connecting member also serves as a damper and an interlock switch rod, an interlock switch mechanism is provided with a simpler structure, and The opening / closing operation of the outer cover can be relaxed.

Since the sheet feeding device and the image forming means for forming an image on the sheet fed by the sheet feeding device are provided, the jam processing is simple and the separating means and the conveying means can be replaced. An easy image forming apparatus can be provided.

Since the sheet feeding device is provided,
It is possible to provide an optional cassette feeder in which jam processing is easy and replacement of the separating means and the conveying means is easy.

A corrugated sheet is provided by providing a pair of conveying rotary members for nipping the sheet and feeding the sheet into the image forming apparatus, and at least one of the pair of conveying rotary members has a width equal to the sheet width to be conveyed. It is possible to control the violence and smooth sheet conveyance.

By having the structural frame body for accommodating the sheet feeding device and the fixing means for positioning and fixing the sheet feeding device from the upper part of the structural frame body, the assembling property is excellent.
An optional cassette feeder can be provided.

[Brief description of drawings]

FIG. 1 is a retard type sheet feeding device embodying the present invention.
Perspective view of the optional cassette feeder with location.

FIG. 2 is a sectional view of a paper path of the optional cassette feeder of FIG.

FIG. 3 is a cross-sectional view of the opening / closing mechanism of the option cassette feeder of FIG.

FIG. 4 is a view of the rotary feeding device as viewed from the downstream side in the sheet feeding direction.

FIG. 5 is a view of the fixed feeding device as viewed from the upstream side in the sheet feeding direction.

FIG. 6 is a diagram showing an opening / closing operation of FIG. 3;

FIG. 7 is a diagram showing an opening / closing operation of FIG. 3;

FIG. 8 is a diagram showing an opening / closing operation of FIG. 3;

FIG. 9 is a diagram showing an opening / closing operation of FIG. 3;

FIG. 10 is a view showing the operation of the switch rod provided on the outer cover.

FIG. 11 is a perspective view showing how the feeding device is attached to the frame.

FIG. 12 is a cross-sectional view showing a combination of a conventional image forming apparatus and an optional cassette feeder.

FIG. 13 is an enlarged view of the conventional feeding device unit of FIG.

FIG. 14 is an enlarged view of the conventional feeding device unit of FIG.

FIG. 15 is a perspective view of an optional cassette feeder of a conventional example.

[Explanation of symbols]

3 Optional conveying roller 4 main feeding cassette 4a option conveying paper feed cassette 7 optional roller 7 a conveyance roller cutout portion 13 extended path 25a feed rollers (conveying means) 27 retard roller (separation means) 34a R lower guide 36a cam portion 37a Pressure release lever 45 Fixed feeding device 46 Conveying roller holder 47 Conveying lower guide 49 Retard roller unit (separating means supporting part) 50 Opening / closing plate 51 Exterior cover 56 Feed roller unit (conveying means supporting part) 57 Paper feeding top plate 60 Paper feeding Right side plate 61 Push link 62 Pulling link (interlocking means) 73 Pressure releasing roller (first contact pressure releasing means) 74 Cam part 75 Rotary feeding device (separating feeding part) 76 Paper feed left side plate 100 Image forming apparatus main body 200 Option Cassette feeder

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B65H 1/00-3/68

Claims (9)

(57) [Claims] 1. A sheet stacking means, a feeding means for feeding the sheets stacked on the sheet stacking means, and a conveying means for applying a force in the sheet conveying direction to the sheets fed from the feeding means. the separating means for applying the sheet conveying direction opposite to the direction of the force to the sheet fed from the means feeding the sheet in contact with the conveying means
It has a rotation around an axis provided on the main body of the device.
The separating means can be separated from the contact position with the conveying means.
The separation feeding unit and the shaft provided outside the rotation center of the separation feeding unit
The outer cover that rotates around the center and the separate feeding section are provided to engage with the pins on the main body of the device.
And a lock lever for fixing the separating / feeding unit, and provided between the separating / feeding unit and the exterior cover.
To open the separate feeding unit when the exterior cover is opened
Provided between the pulling link and the separation feeding unit and the exterior cover,
When the outer cover is closed, the separation feeding unit is closed.
And a push link of the eye, the tension link has not been connected to the lock lever
Lock the lock lever when opening the exterior cover.
The pull link and the push link with the pin and the slot.
Attached to the separate feeding section with
When the relinking opens the separation feeding section,
The pin slides in the long hole on the
When closing the separating / feeding unit, the
The sheet feeding device is characterized in that the slider slides in the long hole . 2. A according to claim 1, further comprising a first contact pressure releasing means for releasing the contact pressure to the conveying means of the separating means in conjunction with the rotation operation of the separating and feeding part Sheet feeding device. 3. The sheet stacking means is detachably mounted in a direction perpendicular to the sheet conveying direction, and releases the contact pressure of the separating means to the conveying means in association with the attaching / detaching operation of the sheet stacking means. The sheet feeding device according to claim 2, further comprising contact pressure releasing means. 4. A transport means supporting portion comprising the transport means and a first drive transmission means for transmitting power to the transport means, and a separation means and a second drive transmission means for transmitting power to the separation means. The sheet feeding device according to any one of claims 1 to 3 , wherein the separating means support portion is detachably provided to the main body of the sheet feeding device. 5. a connecting member for connecting the outer cover and the sheet feeding apparatus main body, of the claims 1 to 4 wherein the connecting member is characterized in that also serves as a damper and the interlock switch rod sheet feeding apparatus according to any one. A sheet feeding apparatus according to any one of 6. The method of claim 1 or 5, further comprising an image forming means for forming an image on the sheet fed by said sheet feeding apparatus A characteristic image forming apparatus. 7. The method of claim 1 to 5 optional cassette feeder images forming device you comprising the sheet feeding apparatus according to any one of the. 8. A conveying rotating body pair which feeds the sandwiched by the images forming apparatus sheet is provided, characterized in that it has a seat width equivalent width of at least one of said conveying rotating body pairs are conveyed The optional cassette feeder according to claim 7 . 9. have a structural frame body for housing the sheet feeding apparatus, according to claim 7, further comprising a fixing means for positioning and fixing the sheet feeding device from the top of the structural frame member
Alternatively, the optional cassette feeder described in 8 .