JP2003081470A - Sheet feeding device, image reading device and image forming device provided with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeding device, an image reading device and an image forming device provided with the same enabling to easily replace a separating roller or the same and capable of separating and feeding sheets regardless of types of sheets. SOLUTION: A transmitting member 6 connecting to a driving power transmitting means 5 to transmit driving power to a separating rotating body 2 when the driving power transmitting means 5 moves to a first position for transmitting driving power from a driving power source to the separating rotating body 2, and the separating rotating body 2 are rotatably and detachably and attachably installed on a device main body 101 as a unit 102, The device is constructed to release connection of the driving power transmitting means 5 and the transmitting member 6 with interlocking with detaching the unit 102 and to connect the driving power transmitting means 5 and the transmitting member 6 with interlocking with attaching the unit 102. Consequently, replacement of the separating roller or the like and connection of driving power can be done by single operation of replacing the unit 102.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus, an image reading apparatus including the sheet feeding apparatus, and an image forming apparatus, and more particularly to a sheet feeding apparatus for separating and feeding sheets one by one using a retard separation method. The present invention relates to one provided with a sending means.

[0002]

2. Description of the Related Art In recent years, an image reading apparatus, an image forming apparatus such as a printer, a copying machine, a facsimile or the like separates sheets one by one and feeds them to an image reading section or an image forming section. It is equipped with a device. As such a sheet feeding device, a device that uses a retard separation system capable of separating the sheet with high reliability from low speed to high speed is widely used as a mechanism for separating the sheet.

In this retard separation system, the feed roller rotating in the sheet feeding direction is pressed against the feed roller at a predetermined pressure and is rotated in the direction opposite to the sheet feeding direction, in other words, in the sheet returning direction. By means of a separating roller (retarding roller), the sheets are separated and fed one by one.

Here, a torque limiter for generating a slip at a predetermined load or more is provided in the drive transmission path of the separation roller, and the torque limiter is usually provided.
It works by a load consisting of a frictional force between the feed roller and the sheet, whereby the separation roller follows the sheet (rotates around) and conveys one sheet.

On the other hand, when a plurality of overlapping sheets enter between the roller nips which are pressed against each other, the sheet contacting the feed roller is conveyed in the feeding direction due to the slip between the sheets, and the sheet contacting the separation roller side is separated by the separation roller. It is designed to be returned by rotating in the reverse direction.

In this case, the friction coefficient between the feed roller and the sheet is μ1, the friction coefficient between the sheets is μ2,
If the friction coefficient between the separation roller and the sheet is μ3, the following conditions are required.

Μ1>μ3> μ2 Further, the inter-roller pressure and the torque limiter value are set in accordance with a sheet that is generally conveyed, and as a minimum condition, the separation roller feeds one sheet when it is conveyed. It is necessary to set it so that it will follow the roller.

By the way, if the separating operation is repeatedly performed under such a condition, the separating roller eventually wears, and the separating operation cannot be performed. Therefore, most of the devices have a structure that allows the user to replace the separation roller.

Next, the conventional separating roller replacement operation will be described with reference to FIGS.

In FIG. 8, reference numeral 15 is a maintenance guide member which is opened when the separation roller 16 is replaced, and when the separation roller 16 is replaced, it is in a closed state as shown in FIG. Maintenance guide member 15
Is opened as shown in (b) so that the periphery including the separation roller 16 is exposed.

On the other hand, in FIG. 9, 18 is the drive supply shaft 1.
The holding member 18 is rotatable about 7, and the holding member 18 is provided with a movable support shaft 19 and a connection support shaft 20. The movable support shaft 19 and the connection support shaft 20 support both ends of the separation roller 16 to rotatably hold the separation roller 16.

When the separating roller 16 is replaced,
First, the maintenance guide member 15 is opened, and thereafter,
By moving the movable support shaft 19 in the direction away from the connection support shaft 20 from the state shown in (a) of the figure, the separation roller 16 is removed as shown in (b).

Next, after detaching the separation roller 16 in this way, one end of the separation roller 16 is first connected to the supporting shaft 20 so that the holding member 18 holds the new separation roller 16.
To the movable support shaft 19
Then, the movable support shaft 19 is moved in a direction of approaching the connection support shaft 20. As a result, the new separating roller 16 is connected to the movable supporting shaft 19 and the connecting supporting shaft 20.
And is held by the holding member 18.

As shown in FIG. 9, the connection support shaft 20 is provided with a small pulley 21 and a torque limiter 23, and the drive supplied from the drive source (not shown) to the drive supply shaft 17 is
The separation roller 16 that is transmitted to the connection support shaft 20 via the drive supply shaft 17, the large pulley 22, the belt 24, the small pulley 21, and the torque limiter 23 that acts as described above, and is connected to the connection support shaft 20. Is designed to rotate forward and backward.

[0015]

However, in such a conventional sheet feeding apparatus, when the separation roller 16 is replaced, the maintenance guide member 15 is first used.
Had to be opened, and then the movable support shaft 19 had to be moved, which required a plurality of operations for the user.

Further, since the structure for pressing the separation roller 16 against the feed roller and the torque limiter 23 for generating the return torque of the separation roller 16 are provided on the apparatus main body side, the coefficient of friction of the sheet surface is extremely low. Alternatively, when it is desired to feed a special sheet such as a high sheet, the sheet cannot be fed unless the apparatus main body is modified so that the pressure contact force and the torque limiter values are the values corresponding to the sheet.

Further, the torque limiter 23 may reach the end of its life by repeating the separating operation. In this case, the torque limiter 23 must be replaced.
Also in this case, the same operation as the replacement work of the separation roller 16 described above is required.

Therefore, the present invention has been made in view of the above circumstances, and a sheet feeding apparatus capable of easily exchanging separation rollers and the like and capable of separating and feeding sheets regardless of the types of sheets. It is an object of the present invention to provide an image reading apparatus and an image forming apparatus including the same.

[0019]

SUMMARY OF THE INVENTION The present invention relates to a sheet feeding device for separating and feeding the sheets stored in a sheet storage portion one by one, and a sheet feeding device that rotates in the sheet feeding direction. A separating body that includes a rotating body and a separating rotating body that rotates the sheet in a direction to return the sheet to the sheet storage unit, and a separating and feeding unit that separates and feeds the sheets one by one, and a driving source for the separating rotating body. A drive transmission mechanism for transmitting drive from the drive transmission mechanism, the drive transmission mechanism being provided on the apparatus main body side and connected to the drive source; and the drive transmission mechanism connected to the separated rotary body. A transmission member for transmitting drive to the separation rotary body when connected to the means, the separation rotary body and the transmission member are unitized, and the unit is detachably provided to the apparatus main body, The drive transmission means It is movably provided in a first position that is connected to a member and a second position that is not connected, and moves the drive transmission means from the second position to the first position in association with the attachment of the unit to the apparatus main body. The connecting means for moving the unit from the first position to the second position is provided in association with the removal of the unit.

According to the present invention, the connecting means moves the drive transmission means to the first position when the unit is attached, and moves the drive transmission means to the second position when the unit is removed. It is characterized in that it is provided with movable arm means for moving.

According to the present invention, the movable arm means is rotatably provided, is urged by an elastic member to position the drive transmission means at the second position, and when the unit is attached, the movable arm means is temporarily moved by the unit. Is pressed and the other end is rotated so as to move the drive transmission means from the second position to the first position, and when the unit is detached, the pressing by the unit is released and the elastic member is used. The drive transmission means is rotated so as to move to the second position.

Further, according to the present invention, the unit has a rotating shaft, and when mounted on the apparatus main body, the unit rotates about the rotating shaft as a fulcrum so as to press the separating rotating body against the feeding rotating body. It is characterized in that it is configured to.

The present invention is also characterized in that the transmission member is arranged coaxially with the rotation shaft of the unit.

Further, the present invention is characterized in that it comprises an urging means for urging the unit so that the separating rotary body is brought into pressure contact with the feeding rotary body.

Further, the present invention is characterized in that a torque limiter mechanism for restricting a rotation torque of the separating rotary body is arranged between the transmitting member and the separating rotary body.

Further, the present invention is characterized in that the torque limiter mechanism and the biasing means are provided in the unit in a replaceable manner.

Further, according to the present invention, an image reading apparatus is provided with the sheet feeding apparatus described in any one of the above, and an image reading unit for reading an image of a document sent from the sheet feeding apparatus. It is a feature.

Further, the present invention is characterized in that the sheet feeding device is provided so as to be openable and closable with a document conveyance path as a boundary.

According to the present invention, in the image forming apparatus, the sheet feeding apparatus described in any one of the above, and the image forming section for forming an image on the sheet fed from the sheet feeding apparatus are provided. It is characterized by.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a view showing the arrangement of an image reading apparatus equipped with a sheet feeding apparatus according to the embodiment of the present invention.
In the figure, 100 is an image reading apparatus, 100A is an image reading apparatus main body, 100B is a sheet stacking section that is a sheet storage section for stacking and storing sheets S, and 103 and 104 are upper and lower image reading sections that read an image of the sheet S. , 100C
Is a sheet feeding device that feeds the sheets S stored in the sheet stacking unit 100B to the upper and lower image reading units 103 and 104.

The sheet feeding device 100C is composed of a feed roller 1 which is a feeding rotating body and a separating roller 2 which is a separating rotating body which is in pressure contact with the feeding roller 1, and the sheets stacked on the sheet stacking unit 100B. It is provided with a separating and feeding means for separating S one by one. 3 is a feed roller 1,
This is a main motor for driving the separation roller 2 and the like.

Next, the image reading operation in the image reading apparatus 100 thus constructed will be described.

When the image reading operation is started, the plurality of sheets S placed on the sheet stacking section 100B are separated into one sheet by the feed roller 1 and the separation roller 2 which are in pressure contact with each other, and then the platen roller 103a. , 104a, while passing in close contact with the upper and lower image reading units 103, 104.

At this time, the image formed on the front surface or the back surface of the sheet S is line-scanned by passing while facing the upper and lower image reading portions 103 and 104, and is output to the outside as an electric signal. Further, after the image is read in this way, the sheet S is ejected onto the sheet ejection roller pair 105a, 1a.
The sheet is discharged to the outside by 05b.

In the figure, reference numeral 101 denotes an upper unit that constitutes the main body of the sheet feeding apparatus including the separating roller 2, the upper image reading unit 103, the upper sheet discharging roller 105a, etc. Is (a) in the figure
Although it is closed as shown in FIG. 2, for example, during jam processing, cleaning and maintenance of rollers, etc., it opens upward as shown in FIG. It is configured to be separated from 1.

Next, the drive transmission mechanism of the separating / feeding means and the connecting means for automatically connecting / disconnecting the drive transmission mechanism will be described with reference to FIG.

In FIG. 2, 10 is a feed gear fixed to the feed roller shaft 1a of the feed roller 1 and connected to the main motor 3 as a drive source via a gear train (not shown), and 11 is an idler gear 11a. The separation drive gear 11 is connected to the feed gear 10 via the separation drive gear 11. The separation drive gear 11 is fixed to the separation drive gear shaft 4. As a result, when the main motor 3 rotates, the feed gear 10 rotates, and accordingly, the feed roller shaft 1a and the separation drive gear shaft 4 rotate.
Rotates.

In FIG. 2, reference numeral 5 denotes a drive supply connecting shaft which is a drive transmitting means which is connected to the separation driving gear shaft 4 and is movable in the axial direction of the separation driving gear shaft 4. Is configured to rotate integrally with the separation driving gear shaft 4 by a connecting portion 4a provided at one end of the separation driving gear shaft 4, and along the connecting portion 4a in the axial direction of the separation driving gear shaft 4. Held to move.

Separate drive gear shaft 4 of this drive supply connecting shaft 5
As shown in FIG. 3, an engaging portion 5a is formed at an end portion on the opposite side to the engaging portion 5a. The engaging portion 5a is a movable driving means for regulating the position of the drive supply connecting shaft 5 and is a separation drive coupling. One end 7b of the lever 7 is locked.

The separation drive connection lever 7 is swingably provided on the upper unit 101 with the shaft 7a as a fulcrum, and the spring 12 which is an elastic member presses the drive supply connection shaft 5 in the separation drive gear axis direction. Is urged to do so.

In the figure, 102 is a separation unit which is detachably mounted on the upper unit 101, and this separation unit 102 is the separation roller 2
And a torque limiter pulley 9 that constitutes a torque limiter mechanism for restricting the rotation torque of the separation roller 2 and the drive supply connection shaft 5 to be selectively connected to transmit the drive from the main motor 3 to the separation roller 2. And a drive transmission connecting pulley shaft 6 which is a transmission member for.

When the drive supply connecting shaft 5 and the drive transmitting connecting pulley shaft 6 are connected as shown in the figure, the drive supplying connecting shaft 5 is rotated so that the drive transmitting connecting pulley shaft 6 and the belt 8 are rotated.
And the torque is transmitted to the separation roller 2 via the torque limiter pulley 9, whereby the separation roller 2 is rotated in the reverse direction with respect to the conveying direction.

As shown in the figure, when the upper unit 101 is closed with the separating unit 102 mounted, the separating and feeding means is formed as shown in FIG.

By closing the upper unit 101 in this way, the separating / feeding means is formed. In this state, when a plurality of sheets S are conveyed and a load larger than the specified torque is applied to the separating roller 2, the torque limiter is applied. The pulley 9 acts, and as a result, the separation roller 2 rotates following the feed roller 1 and the sheet S.

In the figure, 13 is a pressing coil spring 1 for pressing the separation unit 102 to press the separation roller 2 against the feed roller 1 when the upper unit 101 is bound.
Reference numeral 3 denotes a housing of the separation unit 102 that holds the separation roller 2, the drive transmission connecting pulley shaft 6, the belt 8, the torque limiter pulley 9, and the like.

As will be described later, when the separation unit 102 is not incorporated in the upper unit 101, the separation drive connection lever 7 is provided with the spring 1 as shown in FIG. 4 (a).
2, the drive supply connecting shaft 5 is moved in the pressing direction, and the drive supply connecting shaft 5 is moved in the direction of the separation drive gear shaft 4.

Here, a fitting portion 5b for fitting with the drive transmission coupling pulley shaft 6 is provided at the tip of the locking portion 5a of the drive supply coupling shaft 5.
When the drive supply connecting shaft 5 moves in the direction of the separation drive gear shaft 4 in this manner, the fitting portion 5b is
The separation unit storage space G shown in FIG. 5, which will be described later, is retracted.

When the fitting portion 5b is retracted from the separation unit housing space G as described above, the fitting between the drive supply connecting shaft 5 and the drive transmitting connecting pulley shaft 6 is released, and the main motor 3 is attached to the separating roller 2. Drive from is no longer transmitted. That is, when the separation unit 102 is not assembled in the upper unit 101, the drive supply connection shaft 5 is moved by the separation drive connection lever 7 to the second position where the drive of the main motor 3 is not transmitted. In this state, the pressing portion 7c provided at the other end of the separation drive connecting lever 7
Project into the space G for storing the separation unit.

Further, as will be described later, the separation unit 102
Is stored in the separation unit storage space G, the pressing portion 7c of the separation drive connection lever 7 is pressed by the separation unit 102, and the drive supply connection shaft 5 is fitted as shown in FIG. The joint part 5b is the space G for storing the separation unit
The drive transmission coupling pulley shaft 6 is fitted to the shaft 6. That is, the separation unit 102 is the upper unit 1
Drive assembly connecting shaft 5 when assembled in 01
The separation drive connecting lever 7 moves to the first position where the drive from the main motor 3 is transmitted.

When the fitting portion 5b of the drive supply connecting shaft 5 is fitted into the drive transmitting connecting pulley shaft 6, the main motor 3
Is transmitted to the drive transmission connection pulley shaft 6 via the feed gear 10, the separation drive gear shaft 4, and the drive supply connection shaft 5.
This causes the separation roller 2 to rotate. In addition,
The engaging portion 5a of the drive supply connecting shaft 5, the separation drive connecting lever 7, the spring 12 and the like constitute the connecting means of the present invention.

Next, the replacement operation of the separation unit 102 in the image reading apparatus 100 thus configured will be described.

FIG. 5 shows a method of attaching the separation unit 102. Here, bosses 102a, which are two-sided cylinders, are provided on both side wall surfaces of the separation housing 14 of the separation unit 102, and the upper unit 101 has an insertion groove 10 corresponding to the diameter of the two-sided bosses 102a.
1a is provided.

Separation unit 1 inside the insertion groove 101a
02 has a mounting hole 101b corresponding to the circle diameter of the boss 102a at the final mounting position. When mounting the separation unit 102 on the upper unit 101,
First, as shown in (a), the separation unit 102 is attached to the boss 1
02a two-way chamfer and insertion groove 101a on the upper unit side
The boss 102a is inserted up to the position of the mounting hole 101b at an angle corresponding to.

Next, the boss 102a is attached to the mounting hole 1 as described above.
After being inserted to the position of 01b, the separation unit 102 is rotated in the direction to be stored in the separation unit storage space G provided in the separation unit 102 as shown by the arrow in (b) of FIG. It becomes possible to hold both of them.

The separation unit 102 can be removed by
First, the separation unit 102 is rotated in the direction opposite to the arrow of (b), and then the separation unit 102 is extracted along the insertion groove 101a.

By the way, in the state where the separation unit 102 is not incorporated in the upper unit 101 as shown in FIG. 4A, as shown in FIG. The other end 7b is the separation unit 1
Since it is not pressed by 02, the separation drive connecting lever 7 becomes free.

Therefore, as shown in the figure, the separation drive connection lever 7 moves the drive supply connection shaft 5 in the direction of the separation drive gear shaft 4 by the spring force of the lever coil spring 12. Along with this, the fitting portion 5b of the drive supply connecting shaft 5 retracts from the separation unit housing space G, so that the fitting portion 5b does not interfere with the mounting of the separation unit 102.

The separation unit 102 is replaced with the upper unit 101.
When installed on the boss 102a, as shown in FIG.
When the separation unit 102 is rotated after the insertion unit 101 has been inserted to the position of the mounting hole 101b, the pressing portion 7c causes the separation unit 10
It is pressed by 2. As a result, the separation drive connection lever 7 is rotated to press the drive supply connection shaft 5, and as a result,
As shown in FIG. 4B, the fitting portion 5 of the drive supply connecting shaft 5
b projects into the space G for storing the separation unit and fits into the drive transmission connecting pulley shaft 6.

In this way, the fitting portion 5b of the drive supply connecting shaft 5 is
When the drive transmission connection pulley shaft 6 and the drive transmission connection pulley shaft 6 are fitted together, the separation unit 102 is held by the drive supply connection shaft 5 at the position rotated upward, and when the main motor 3 rotates, the rotation thereof causes the feed gear 10 and the separation drive. It is transmitted to the drive transmission connecting pulley shaft 6 via the gear shaft 4 and the drive supply connecting shaft 5, whereby the separation roller 2 rotates.

As described above, when the separation unit 102 is mounted on the upper unit 101, the end surface of the pressing coil spring 13 abuts on the upper unit 101.
As a result, when the upper unit 101 is closed, the separation unit 102 is pressed by the pressing coil spring 13 in the rotation range position according to the usage situation as shown in FIG. 6, and as a result, the separation roller 2 is fed by the feed roller 1. It is designed to be pressed against.

When the separation roller 2 is pressed against the feed roller 1 by the pressing coil spring 13 as described above, the upward rotation of the separation unit 102 is restricted by the upper unit 101 shown in FIG. 5B. Hook 1 provided
01b and the convex portion 102 provided in the separation unit 102.
and b.

In this way, the separation roller 2, the drive transmission connecting pulley shaft 6, the pressing coil spring 13, the torque limiter pulley 9 and the like are integrally provided as a separation unit 102, and the separation unit 102 is rotated and detached from the upper unit 101. The detachable unit 102 is mounted so that it can be mounted, and the drive supply coupling shaft 5 and the drive transmission coupling pulley shaft 6 are coupled in association with the mounting of the separation unit 102. , Separation roller 10
The two can be exchanged and the drive can be coupled so that the separation roller 102 can be easily exchanged.

By the way, in the present embodiment, not only the separation roller 2, but also the pressing coil spring 13 and the torque limiter pulley 9 are replaceably attached to the separation unit 102.

The torque value of the torque limiter pulley 9 and the spring force of the pressing coil spring 13 are determined by examination and evaluation according to the type of the sheet S. For example, for a sheet that has a small friction coefficient with respect to the rollers and is slippery, if the spring force of the pressing coil spring 13 is increased to increase the pressure between the rollers and the value of the normal force applied between the sheets increases, For a sheet having a large friction coefficient, the torque value of the torque limiter pulley 9 is set to a small value.

Here, as in the present invention, the separation unit 10
2 can be easily replaced, and the pressing coil spring 13 and the torque limiter pulley 9 are replaceably attached to the separation unit 102. In other words, the predetermined pressing coil spring 13 and the torque limiter pulley 9 are attached. By detachably attaching the separating unit 102 to the upper unit 101, it is possible to handle various types of sheets without modifying the sheet feeding apparatus main body. Further, the separation unit 102
When the whole is replaced, the torque limiter pulley 9 is also replaced, so that the product life is improved.

In the above description, the sheet feeding device 100C is used as the feed roller 1 and the separation roller 2.
Although the configuration in which and are brought into pressure contact with each other has been described as an example, the present invention is not limited to this, and for example, as shown in FIG.
Is also effective in a sheet feeding device having a configuration in which the separation roller 2 and the separation roller 2 are not in contact with each other.

In the above description, the case where the separation drive connection lever 7 is provided on the upper unit side has been described, but the present invention is not limited to this, and the separation drive connection lever 7 is provided on the separation unit side, and The same effect can be obtained by fixing the drive supply connecting shaft 5 except in the rotation direction and moving the drive transmitting connecting pulley shaft 6.

Further, in the above description, the sheet feeding device provided in the image reading apparatus has been described as an example, but the present invention is not limited to this, and the image forming apparatus having the image forming section is provided. It can also be applied to the sheet feeding device provided in the.

[0070]

As described above, as in the present invention, the connection between the drive transmission means and the transmission member is released in association with the removal of the unit, and the drive transmission means and the transmission member are connected in association with the attachment of the unit. By configuring so as to be connected, the separation roller and the like can be exchanged and the drive can be connected by only a single operation of attaching and detaching the unit, and the separation roller and the like can be easily exchanged. Also, by making it possible to replace the unit with a unit that fits the sheets, it is possible to separate and feed various types of sheets.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an image reading apparatus including a sheet feeding apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view illustrating a drive mechanism of a separation feeding unit of the sheet feeding apparatus.

FIG. 3 is a plan view illustrating a drive mechanism of the separating and feeding unit.

FIG. 4 is a perspective view illustrating the operation of a separation drive connection lever provided in the sheet feeding device.

FIG. 5 is a perspective view showing a method for attaching and detaching the separation unit of the sheet feeding device.

FIG. 6 is a side view of a main part of the sheet feeding device.

FIG. 7 is a perspective view illustrating a drive mechanism of a separation feeding unit in a sheet feeding apparatus according to another embodiment of the present invention.

FIG. 8 is a first diagram illustrating a conventional separating roller replacement operation.

FIG. 9 is a second diagram illustrating a conventional separating roller replacement operation.

[Explanation of symbols]

1 Feed roller 2 Separation roller 3 main motor 4 Separate drive gear shaft 5 Drive supply connecting shaft 6 Drive transmission connecting pulley shaft 7 Separate drive connection lever 9 Torque limiter pulley 12 lever coil spring 13 Pressing coil spring 100 image reading device 100A image reading device body 100B sheet stacking section 100C sheet feeding device 101 Upper unit 102 separation unit 103 Upper image reading unit 104 Lower image reading unit G Separation unit storage space S sheet

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Claims (11)

[Claims] 1. A sheet feeding device that separates and feeds sheets stored in a sheet storage unit one by one, and a feeding rotating body that rotates in a feeding direction of the sheet and the sheet. A separating / rotating body that rotates in the direction of returning to the sheet storage portion, and a separating / feeding unit that separates and feeds the sheets one by one; and a drive for transmitting drive from a drive source to the separating / rotating body. A transmission mechanism, wherein the drive transmission mechanism is provided on the apparatus main body side, and is driven when the drive transmission means is connected to the drive source and the drive transmission means is connected to the separated rotating body and the drive transmission means. And a transmission member for transmitting to the separation rotating body, the separation rotating body and the transmission member are unitized, and the unit is detachably provided to the apparatus main body, and the drive transmission means is the transmission member. The first place to connect with Movable in a second position not connected with, the device a second said drive transmitting means in conjunction with the attachment to the body of the unit
2. A sheet feeding apparatus, comprising: a connecting unit for moving from a position to the first position and for moving the unit from the first position to the second position in association with the removal of the unit. 2. The movable means for moving the drive transmission means to the first position when the unit is attached, and to move the drive transmission means to the second position when the unit is detached. The sheet feeding device according to claim 1, further comprising arm means. 3. The movable arm means is rotatably provided, is urged by an elastic member to position the drive transmission means to the second position, and one end of the movable arm means is pressed by the unit when the unit is attached. And the other end rotates so as to move the drive transmission means from the second position to the first position, and when the unit is detached, the pressing by the unit is released and the elastic member transmits the drive transmission. 3. The sheet feeding apparatus according to claim 2, wherein the means is rotated so as to move the means to the second position. 4. The unit has a rotating shaft, and when mounted on the apparatus main body, the unit rotates about the rotating shaft as a fulcrum so as to press the separating rotating body against the feeding rotating body. The sheet feeding device according to claim 1, wherein the sheet feeding device is configured. 5. The sheet feeding apparatus according to claim 4, wherein the transmission member is arranged coaxially with a rotation shaft of the unit. 6. The sheet feeding apparatus according to claim 4, further comprising an urging means for urging the unit so that the separating rotary body is pressed against the feeding rotary body. 7. The torque limiter mechanism for restricting the rotational torque of the separating rotary body is arranged between the transmission member and the separating rotary body. The sheet feeding device described in. 8. The sheet feeding apparatus according to claim 7, wherein the torque limiter mechanism and the urging means are provided in the unit in a replaceable manner. 9. A sheet feeding device according to claim 1, and an image reading unit for reading an image of a document sent from the sheet feeding device. Image reading device. 10. The image reading apparatus according to claim 9, wherein the sheet feeding device is provided so as to be openable and closable with a document conveyance path as a boundary. 11. A sheet feeding device according to claim 1, and an image forming unit for forming an image on a sheet fed from the sheet feeding device. A characteristic image forming apparatus.