JP2011020797A - Document feeder and image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To send out a document in a state of enabling a sending-out roll to secure pressurizing force to the document side, while realizing space-saving in a device and restraint of a weight increase. <P>SOLUTION: This document feeder comprises the sending-out roll 13 for sending out the document by contacting with the document positioned on the uppermost surface of a document bundle placed on a document tray, a roll support part 94 for displacing a vertical directional position of the sending-out roll 13 in response to a thickness of the document bundle, and an elastic member 95 for applying energizing force to the document bundle side to the sending-out roll 13 by using elastic deformation. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a document feeder and an image forming apparatus.

  A document feeder known as ADF (auto document feeder), DADF (Duplex auto document feeder), or the like conveys each document constituting a document bundle to be processed on a leaf-by-leaf basis. For this purpose, the document feeder includes a feed roll that feeds the document in contact with the document located on the uppermost surface of the document bundle. However, since the thickness of the document bundle is not always constant, the sending roll is displaced in the vertical direction according to the thickness of the document bundle (see, for example, Patent Document 1). .

JP 2009-67559 A

In order for the delivery roll to deliver the uppermost document, in addition to the vertical position of the delivery roll being displaced, the delivery roll is the uppermost document being pressed with a certain amount of force. It is necessary to be in contact with.
In general, pressurization of the delivery roll to the document side is performed by utilizing the weight of the delivery roll itself or a member attached to the delivery roll. Therefore, if an attempt is made to secure a pressing force on the side of the document, there is a possibility that an additional space such as a member that becomes a weight may be required. Further, it is conceivable that the attachment of a member or the like serving as a weight causes an increase in the weight of the device and a deterioration in operability associated with the increase in weight (for example, a deterioration in operability when opening and closing the cover). These are contrary to the recent demands for downsizing and weight reduction of the entire apparatus.
The present invention realizes space saving in the apparatus and suppression of weight increase of the entire apparatus, and even in such a case, the original is fed in a state in which the pressure applied to the original side of the feeding roll is ensured. An object of the present invention is to provide a document feeder and an image forming apparatus capable of performing the above.

According to a first aspect of the present invention, there is provided a feed roll for sending a document in contact with a document positioned on the uppermost surface of the document bundle placed on the document table, and corresponding to the thickness of the document bundle. An original feeding apparatus comprising: a roll supporting portion that displaces a vertical position of the feeding roll; and an elastic member that applies an urging force to the feeding roll toward the original bundle by using elastic deformation. It is.
The invention according to claim 2 is the document feeder according to claim 1, wherein the elastic member is a compression coil spring.
The invention according to claim 3 is characterized in that the roll support portion has a fulcrum of vertical displacement of the delivery roll at one end and an action point supporting the delivery roll at the other end, the fulcrum and the action point. The document feeder according to claim 1, wherein the document feeding device is configured to have a force point to which a force by the elastic member is applied.
According to a fourth aspect of the present invention, there is provided an image feeding device that transports a document to be read, an image reading device that reads an image from a document transported by the document feeding device, and an image reading by the image reading device. An image recording device for outputting an image on a recording medium based on the result, and the document feeding device sends the document in contact with a document positioned on the uppermost surface of the document stack placed on the document table. A feeding roll that performs the scanning, a roll support portion that displaces the vertical position of the feeding roll in accordance with the thickness of the document bundle, and the side of the document bundle to the feeding roll using elastic deformation And an elastic member for applying an urging force to the image forming apparatus.

According to the first and fourth aspects of the invention, since pressure is applied using elastic deformation, pressure is applied using the weight of the delivery roll itself or a member provided along with the delivery roll. Compared to the case, it is possible to easily reduce the space in the apparatus necessary for the pressurization, and it is also possible to suppress an increase in the apparatus weight.
According to the invention which concerns on Claim 2, the pressurization using an elastic deformation can be reliably performed with a simple structure, and it is effective to implement | achieve space saving in an apparatus.
According to the invention according to claim 3, since the force point is arranged between the fulcrum and the action point, compared to the case where the force point is located between these fulcrum and the action point but outside them, An increase in the size of components such as a roll support portion can be suppressed, which is effective for realizing space saving in the apparatus.

1 is a schematic diagram illustrating a schematic configuration example of an image forming apparatus according to the present invention. FIG. 3 is a side cross-sectional view illustrating a configuration example of a main part of a document feeder according to the present invention. FIG. 3 is a plan view illustrating a configuration example of a main part of the document feeder according to the present invention.

  A document feeder and an image forming apparatus according to the present invention will be described below with reference to the drawings.

[Configuration example of image forming apparatus]
First, a configuration example of the image forming apparatus will be described.
FIG. 1 is a schematic diagram illustrating a schematic configuration example of an image forming apparatus according to the present invention.

As illustrated, the image forming apparatus 100 includes an image reading device 10 and an image recording device 110.
The image reading apparatus 10 is arranged on the upper part of the image forming apparatus 100, reads an image of a document, and converts the read image into an image signal.
The image recording apparatus 110 is disposed below the image forming apparatus 100 and records an image on a recording medium P such as paper based on the image signal converted by the image reading apparatus 10.

[Configuration example of image recording apparatus]
Here, a configuration example of the image recording apparatus 110 will be described.

  The image recording apparatus 110 includes a plurality of recording medium storage units 120 and 121 in which the recording medium P is stored. The recording medium storage units 120 and 121 store recording media P of different sizes. For example, the recording medium accommodating unit 120 accommodates a B5 size recording medium P, and the recording medium accommodating unit 121 accommodates a B4 size recording medium P.

  Immediately above the leading end side (right end side in FIG. 1) of the recording medium accommodating portions 120 and 121, the recording medium P rotates in contact with the leading end side of the upper surface of the recording medium P, and the recording medium P is sent out from the recording medium accommodating portions 120 and 121. A delivery roll 126 is arranged.

  In the image recording apparatus 110, a conveyance path 122 is formed that extends from the leading ends of the recording medium accommodating portions 120 and 121, curves in an S shape, and extends toward the top of the image recording apparatus 110. A plurality (for example, six) of conveying roll pairs 164 for sandwiching and conveying the recording medium P and a resist roll 168 are arranged along the conveying path 122 in order from the upstream side in the conveying direction of the recording medium.

  An image recording unit 130 that records an image on the recording medium P is disposed above the recording medium accommodating unit 121. The recording medium P accommodated in the recording medium accommodating portions 120 and 121 is sent out by the delivery roll 126, transported through the transport path 122 by the transport roll pair 164 and the registration roll 168, and sent to the image recording section 130.

  The image recording unit 130 is configured to form a color image on the recording medium P using cyan, magenta, yellow, and black toners on the recording medium P sent from the recording medium storage units 120 and 121. . For this purpose, four photosensitive drums 112 are arranged in the image recording unit 130 so as to rotate side by side. Each photoconductive drum 112 is rotated in the direction of arrow K by a driving unit (not shown).

  A charging roller 114 is disposed on the lower left diagonal portion of each photosensitive drum 112 so as to contact the photosensitive drum 112. The charging roller 114 charges the surface of the photosensitive drum 112 to a predetermined potential. After charging, exposure is performed by light emitted from each exposure head 116 disposed below each photosensitive drum 112, and a latent image corresponding to the image signal converted by the image reading device 10 is formed on the surface of the photosensitive drum 112. Formed.

  Each color toner charged to a predetermined polarity is held on the developing roller 119 of each color developer 118. The latent image formed on the surface of each photosensitive drum 112 is developed by applying a developing bias to the developing roller 119 and becomes a toner image of each color.

  Each color toner image formed on each of the four photosensitive drums 112 is transferred by the first transfer roller 115 onto the intermediate transfer belt 113 disposed above each of the photosensitive drums 112, and is transferred onto the intermediate transfer belt 113. To be a full-color toner image.

  The recording medium P sent out from the recording medium storage units 120 and 121 and transported by the transport roller pair 164 is sent to the nip portion between the second transfer roller 132 and the intermediate transfer roller 134 at a preset timing by the registration roller 168. Then, the full color toner image is transferred to the recording medium P. The toner image is transferred to the surface of the recording medium P on the intermediate transfer roller 134 side.

  The recording medium P on which the full-color toner image is transferred is sent to the fixing device 136. The fixing device 136 fixes the toner image on the recording medium P with heat and pressure. The recording medium P on which the toner image is fixed is discharged to the paper discharge tray 140 by the discharge roller 142.

  Note that the toner image is not completely transferred to the intermediate transfer belt 113 and the recording medium P, and a part of the toner image remains on the photosensitive drum 112 and the intermediate transfer belt 113 as residual toner. Residual toner on the photosensitive drum 112 is removed by a cleaning roll 144, and residual toner on the intermediate transfer belt 113 is removed by a cleaning device 138.

[Schematic configuration example of image reading apparatus]
Next, a schematic configuration example of the image reading apparatus 10 will be described.

  The image reading device 10 has a function as a document feeding device that transports a document to be read, and reads an image from a document transported by the document feeding device. More specifically, the document tray 11, the transport unit 37, the discharge tray 40, and the like realize a function as a document feeding device, and the reading unit 70 and the processing device 80 read an image from a document and read the read image signal. Processing is to be performed.

  For this purpose, the image reading apparatus 10 includes a document tray 11 as an example of a document table on which documents of different sizes are placed, and a tray lifter 12 that raises and lowers the document tray 11. On the document tray 11, documents of different sizes, that is, documents having at least one of a document length that is a distance along the document feeding direction A and a document width that is a distance along a direction orthogonal to the document feeding direction A are different. It is supposed to be placed.

  In addition, the image reading apparatus 10 includes a conveyance unit 37 that separates a bundle of documents placed on the document tray 11 one by one and conveys them to the discharge tray 40.

  The transport unit 37 is fed by the feed roll 13 that feeds the document from the document tray 11 raised by the tray lifter 12, the feed roll 14 that transports the document fed by the feed roll 13 to the downstream side, and the feed roll 13. A separation roll 15 is provided for separating the originals one by one.

Further, the transport unit 37 includes a first transport path 31 through which a document sent from the document tray 11 is transported first. In this first conveyance path 31, a takeaway roll 16 that conveys the originals separated one by one to a downstream roll, a pre-registration roll 17 that conveys the original to a further downstream roll and creates a loop, and temporarily After stopping, the rotation is restarted at the same timing, the registration roll 18 for supplying the original while performing registration adjustment to the reading unit 70, the platen roll 19 for assisting the conveyance of the original being read, and the read original An out-roll 20 is provided for transporting downstream.
The first conveyance path 31 is provided with a baffle 41 that rotates around a fulcrum according to the loop state of the document being conveyed.

A second transport path 32 and a third transport path 33 are provided on the downstream side of the out-roll 20. At the branch between the second conveyance path 32 and the third conveyance path 33, a conveyance path switching gate 42 for switching the second conveyance path 32 and the third conveyance path 33 is provided.
On the downstream side of the second conveyance path 32, a discharge tray 40 is provided as an example of a discharge unit that discharges a document that has been read. A first discharge roll 21 that discharges the document to the discharge tray 40 is provided in the second conveyance path 32.

Further, a fourth conveyance path 34 is formed on the downstream side of the third conveyance path 33 for switching back the document that has passed through the third conveyance path 33.
The fourth transport path 34 is provided with an inverter roll 22 and an inverter pinch roll 23 for switching back the document.
A fifth transport path 35 that guides the document switched back by the fourth transport path 34 to the first transport path 31 again passes through the fourth transport path 34 and the first transport path 31.
A sixth transport path 36 for discharging the document switched back by the fourth transport path 34 to the discharge tray 40 communicates with the fourth transport path 34. The sixth transport path 36 is provided with an exit switching gate 43 that switches the transport path of the second discharge roll 24, the fifth transport path 35, and the sixth transport path 36 that transports the reversely discharged document to the first discharge roll 21. It has been.

The delivery roll 13 is lifted up and held at the retracted position during standby, and descends to the nip position (original conveyance position) during conveyance of the document to convey the uppermost document on the document tray 11.
The feed roll 13 and the feed roll 14 convey a document by connecting a feed clutch (not shown). The pre-registration roll 17 makes a loop by abutting the leading end of the document against the stopped registration roll 18. In the registration roll 18, when the loop is created, the leading edge of the document bitten by the registration roll 18 is returned to the nip position. When this loop is formed, the baffle 41 opens around the fulcrum and functions so as not to disturb the document loop.

  Further, the take away roll 16 and the pre-registration roll 17 hold a loop during reading. By this loop formation, the read timing can be adjusted, and the skew associated with the document conveyance at the time of reading can be suppressed, and the alignment adjustment function can be enhanced. In synchronization with the reading start timing, the stopped registration roll 18 starts rotating and is pressed against the second platen glass 72B by the platen roll 19 to read image data from the lower surface direction.

  The conveyance path switching gate 42 switches so that the document passing through the out-roll 20 is guided to the second conveyance path 32 and discharged to the discharge tray 40 at the end of reading one-sided document and at the same time when reading both-side documents simultaneously. It is done. On the other hand, the transport path switching gate 42 is switched so as to guide the document to the third transport path 33 in order to invert the document when the double-sided document is sequentially read. The inverter pinch roll 23 is retracted with the feed clutch (not shown) turned off when the double-sided original is sequentially read, and the nip is released, leading the original to the inverter path (fourth conveyance path 34). Thereafter, the inverter pinch roll 23 is nipped, the original to be inverted by the inverter roll 22 is guided to the pre-registration roll 17, and the original to be reversed is conveyed to the second discharge roll 24 in the sixth conveyance path 36.

  The reading unit 70 is provided in the lower part of the image reading device 10 and reads an image of the document conveyed by the conveying unit 37. The reading unit 70 forms a first platen glass 72A for placing a document to be read in a stationary state on an apparatus frame 71 that forms a housing, and an opening for light to read the document being conveyed. A second platen glass 72B is provided.

  Further, the reading unit 70 is stationary under the second platen glass 72B, and scans the entire first platen glass 72A to read an image, and combines the light obtained from the full rate carriage 73 with an image. A half-rate carriage 75 is provided to provide a portion. The full-rate carriage 73 includes an illumination lamp 74 that irradiates light on the original and a first mirror 76A that receives reflected light obtained from the original. Further, the half-rate carriage 75 is provided with a second mirror 76B and a third mirror 76C that provide the light obtained from the first mirror 76A to the imaging unit.

  Further, the reading unit 70 includes an imaging lens 77 that optically reduces the optical image obtained from the third mirror 76C, and a CCD (Charge Coupled Device) that photoelectrically converts the optical image formed by the imaging lens 77. ) An image sensor 78 and a drive substrate 79 provided with the CCD image sensor 78 are provided, and an image signal obtained by the CCD image sensor 78 is sent to the processing device 80 via the drive substrate 79. The processing device 80 is adapted to send an image signal to the exposure head 116.

  Here, first, when reading an image of a document placed on the first platen glass 72A, the full rate carriage 73 and the half rate carriage 75 move in the scanning direction (arrow direction) at a ratio of 2: 1. At this time, the light of the illumination lamp 74 of the full rate carriage 73 is applied to the surface to be read of the document, and the reflected light from the document is reflected in the order of the first mirror 76A, the second mirror 76B, and the third mirror 76C. Then, it is guided to the imaging lens 77. The light guided to the imaging lens 77 forms an image on the light receiving surface of the CCD image sensor 78. The CCD image sensor 78 is a one-dimensional sensor and processes one line at the same time. When reading of one line in this line direction (main scanning direction of scanning) is completed, the full-rate carriage 73 is moved in a direction (sub-scanning direction) orthogonal to the main scanning direction to read the next line of the document. By executing this over the entire document size, reading of one page of the document is completed.

  On the other hand, the second platen glass 72B is constituted by a transparent glass plate having a long plate-like structure, for example. The document conveyed by the conveyance unit 37 passes over the second platen glass 72B. At this time, the full-rate carriage 73 and the half-rate carriage 75 are stopped at the solid line positions shown in FIG. First, the reflected light of the first line of the document that has passed through the platen roll 19 of the transport unit 37 is imaged by the imaging lens 77 via the first mirror 76A, the second mirror 76B, and the third mirror 76C, and then the CCD. An image is read by the image sensor 78. That is, after one line in the main scanning direction is simultaneously processed by the CCD image sensor 78 that is a one-dimensional sensor, the next line in the main scanning direction of the original conveyed by the conveyance unit 37 is read. After the leading edge of the document reaches the reading position of the second platen glass 72B, the document passes through the reading position of the second platen glass 72B, whereby reading of one page is completed in the sub-scanning direction.

[Example of main part configuration of document feeder]
Next, a characteristic configuration example of the main part of the document feeder included in the image reading apparatus 10 will be described.

FIG. 2 is a sectional side view showing an example of the configuration of the main part of the document feeder according to the present invention.
As shown in the figure, in the image reading apparatus 10, a conveyance unit 37 corresponding to one component of the document feeding apparatus includes a feeding roll 13. The delivery roll 13 is driven to rotate while being in contact with a document located on the uppermost surface of a bundle of documents placed on a document tray 11 as an example of a document table, thereby delivering the document.
Further, on the downstream side in the document transport direction from the delivery roll 13, the feed roll 14 that transports the document sent out by the delivery roll 13 to the further downstream side, and the document sent out by the delivery roll 13 are 1 And a separation roll 15 for separating the sheets one by one. The feed roll 14 and the separation roll 15 are disposed so as to face each other.

The upper side of the feed roll 13, the feed roll 14, and the separation roll 15 is covered with an exterior cover 91. The exterior cover 91 is configured so that it can be opened and closed to deal with a paper jam of a document to be conveyed.
Further, an upper guide plate 92 a and a lower guide plate 92 b that constitute the first transport path 31 are disposed downstream of the feed roll 14 and the separation roll 15 in the document transport direction. The upper guide plate 92a and the lower guide plate 92b guide the document sent out by the feed roll 14.
On the other hand, an upper chute plate 93a and a lower chute plate 93b for guiding the document on the document tray 11 between the feed roll 14 and the separation roll 15 are provided upstream of the feed roll 14 and the separation roll 15 in the document conveyance direction. It is arranged. It is assumed that the upper chute plate 93a is provided at a position that avoids interference with the feed roll 13. The lower chute plate 93b does not necessarily have to be formed as a separate member from the document tray 11, and the document tray 11 may function as the lower chute plate 93b.

Incidentally, the feed roll 13 is supported by a roll support portion 94. One end of the roll support portion 94 is supported coaxially with the feed roll 14, and the other end swings around the support point. The feed roll 13 is supported on the swing end side. Therefore, when the feed roll 13 is supported by the roll support portion 94, the vertical position of the rotation shaft can be displaced. That is, the feed roll 13 is supported by the roll support portion 94 so as to move between the retracted position and the document transport position, and further, the document bundle on the document tray 11 at the document transport position. The vertical position is displaced corresponding to the thickness of the plate.
The roll support portion 94 may be formed using, for example, a molding process of a resin material, but is not limited to this, and is formed using another known method. It doesn't matter.

A compression coil spring 95 that is an example of an elastic member is interposed between the roll support portion 94 and the exterior cover 91. The compression coil spring 95 utilizes the elastic deformation of the compression coil spring 95 (that is, deformation within a range not exceeding the yield point of the forming material), and the document roll side (that is, the lower side) to the feed roll 13. It has come to give the urging power to.
The compression coil spring 95 applies an urging force to the feed roll 13 by applying a pressing force to the roll support portion 94. At this time, the compression coil spring 95 applies a pressing force to a portion located between the feed roll 13 and the feed roll 14. Therefore, the pressed roll support portion 94 compresses between the fulcrum and the action point the fulcrum of the displacement of the feed roll 13 in the vertical direction at one end and the action point supporting the delivery roll 13 at the other end. Each has a force point to which a force by the coil spring 95 is applied.
In order to fix the position of the compression coil spring 95, each of the exterior cover 91 and the roll support portion 94 may be formed with either a concave portion or a convex portion that engages with the compression coil spring 95.
Here, the compression coil spring 95 is cited as an example of the elastic member, but a tension coil spring, a torsion (torsion) spring, and a rubber member can be used as long as they can urge the feed roll 13 using elastic deformation. It is also conceivable to use other elastic members such as.

FIG. 3 is a plan view showing a configuration example of a main part of the document feeder according to the present invention.
As shown in the figure, the rotation shaft of the feed roll 13 and the rotation shaft of the feed roll 14 are connected by a drive transmission mechanism 96 including a pulley and a belt. Therefore, when the feed roll 14 is rotationally driven by a drive source (not shown), the feed roll 13 is also synchronously driven in conjunction with this.
In such a configuration, one end of the roll support portion 94 that supports the feed roll 13 is supported coaxially with the feed roll 14. Therefore, even when the delivery roll 13 is driven synchronously in conjunction with the feed roll 14, the drive transmission is transmitted by the drive transmission mechanism 96 that connects the rotation axis of the delivery roll 13 and the rotation axis of the feed roll 14. Can be done. That is, unlike the case where the swing fulcrum is not coaxial with the feed roll 14, the drive transmission mechanism 96 is not complicated.

[Processing and operation of the document feeder]
In the image reading apparatus 10 having the transport unit 37 configured as described above, when a bundle of documents is placed on the document tray 11, the tray lifter 12 raises the document tray 11 as needed, and the feed roll 13 Lower to the document transport position. Then, the rotational driving force is transmitted to the delivery roll 13 by the drive transmission mechanism 96 in a state where the delivery roll 13 is in contact with the document located on the uppermost surface of the document stack placed on the document tray 11. As a result, the uppermost document in contact with the delivery roll 13 is sent out downstream in the document transport direction.

  At this time, a pressing force from the compression coil spring 95 is applied to the feed roll 13 via the roll support portion 94. That is, the feeding roll 13 is given a biasing force toward the document bundle side. Accordingly, the feeding roll 13 is brought into contact with the uppermost document in a state where it is pressurized with a certain force, so that the uppermost document can be fed without slipping or the like. Become.

  The urging force applied to the delivery roll 13 is generated by utilizing the elastic deformation of the compression coil spring 95. Therefore, for example, as compared with the case where pressure is applied using its own weight such as the delivery roll 13 itself or a weight member attached to the delivery roll 13, the occupation in the apparatus necessary for the pressurization is increased. Space is small. Furthermore, the weight of the components in the apparatus required for the pressurization can be reduced. If an attempt is made to secure the dead weight necessary for pressurization, the volume and weight of the constituent elements are considered to be increased accordingly. However, if pressurization is performed using the elastic deformation of the compression coil spring 95, the compression coil spring 95 This is because the required urging force can be obtained depending on the setting of the spring constant.

  In particular, when the compression coil spring 95 is used as an elastic member for applying an urging force, it is necessary depending on the interval between the roll support portion 94 and the exterior cover 91 and the setting of the free length and the spring constant of the compression coil spring 95. The urging force that will be obtained. That is, a necessary and sufficient urging force can be obtained even with a simple configuration in which the compression coil spring 95 is interposed between the roll support portion 94 and the exterior cover 91. Therefore, the urging | biasing with respect to the delivery roll 13 can be reliably performed with a simple structure.

  Further, when the pressurization point by the compression coil spring 95 is positioned between the feed roll 13 and the feed roll 14, the force point is positioned between the fulcrum and the action point. Therefore, since the force point is arranged between the fulcrum and the action point, the constituent elements such as the roll support portion 94 are compared with the case where the force point is located not between the fulcrum and the action point but outside them. Is small and light.

  By the way, in the transport unit 37 included in the image reading apparatus 10, for example, when a paper jam occurs in the document, the exterior cover 91 is opened and the jammed document is removed. More specifically, each configuration of the feed roll 13, the feed roll 14, and the like positioned above the first conveyance path 31 (that is, between the upper guide plate 92 a and the lower guide plate 92 b). The element is opened together with the exterior cover 91. As a result, a document jammed in the middle of conveyance due to some cause is removed.

  In that case, it is possible to reduce the size and weight of each component that is opened and closed integrally with the exterior cover 91 and the space inside the device that accommodates each component. It is very effective in improving the performance. In this regard, as described above, if the urging force is applied to the delivery roll 13 by utilizing the elastic deformation of the compression coil spring 95, when pressurizing using the weight of the delivery roll 13 or the like is performed. In comparison, space saving in the apparatus and suppression of weight increase can be achieved, so that operability when dealing with paper jams is improved.

  Furthermore, the reduction of the in-device space between the first transport path 31 and the exterior cover 91 leads to the reduction of the overall height direction dimension of the image reading device 10. The same applies to the overall height dimension of the image forming apparatus 100 that includes the image reading apparatus 10. That is, it contributes to downsizing of the entire apparatus.

In addition, although this embodiment demonstrated the suitable Example of this invention, this invention is not limited to the content.
That is, the present invention is not limited to the contents described in the present embodiment, and may be changed without departing from the gist thereof.

  DESCRIPTION OF SYMBOLS 10 ... Image reading apparatus, 11 ... Document tray, 13 ... Sending roll, 14 ... Feed roll, 37 ... Conveying part, 40 ... Discharge tray, 70 ... Reading part, 80 ... Processing apparatus, 94 ... Roll support part, 95 ... Compression coil spring, 100 ... image forming apparatus, 110 ... image recording apparatus

Claims (4)

A sending roll for sending the document in contact with the document located on the uppermost surface of the document stack placed on the document table;
A roll support portion for displacing the vertical position of the feed roll corresponding to the thickness of the document bundle;
An original feeding device comprising: an elastic member that applies an urging force to the feeding roll to the feeding roll using elastic deformation. The document feeder according to claim 1, wherein the elastic member is a compression coil spring. The roll support part has a fulcrum of vertical displacement of the delivery roll at one end, and an action point supporting the delivery roll at the other end between the fulcrum and the action point. The document feeder according to claim 1, wherein the document feeding device is configured so as to have a force point to which each is applied. An image reading device having a document feeding device for transporting a document to be read, and reading an image from a document transported by the document feeding device;
An image recording apparatus that outputs an image on a recording medium based on an image reading result in the image reading apparatus,
The document feeder is
A sending roll for sending the document in contact with the document located on the uppermost surface of the document stack placed on the document table;
A roll support portion for displacing the vertical position of the feed roll corresponding to the thickness of the document bundle;
An image forming apparatus comprising: an elastic member that applies an urging force toward the document bundle side to the feeding roll using elastic deformation.

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