JP2589300Y2 - Sheet transport device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying device used for an image input unit of an image processing device such as a copying machine or an image reader.

[0002]

2. Description of the Related Art Conventionally, a document (sheet) is input to an image input unit of an image processing apparatus such as a facsimile, a copying machine, an image reader, and the like.
The paper feed tray and the paper output tray are disposed vertically above and below, and the documents placed on the paper feed tray are separated and fed one by one to a transport path by a separation roller. The document that has been read is discharged in a U-turn manner to a discharge tray disposed below the paper feeding unit, and when a paper jam occurs, the document is easily removed. For this reason, there is a configuration in which the sheet feeding unit can be opened upward.

FIG. 5 is a longitudinal sectional view showing the overall structure of an image reading apparatus in which a conventional sheet conveying apparatus of this kind is integrated. A sheet conveying apparatus A is mounted on an image reading section B via a hinge C. When the original placed on the glass 2 is removed, the sheet conveying device A can be rotated clockwise to open the upper surface of the glass 2.

In the sheet conveying apparatus A, a sheet feeding unit 3 for stacking an original for reading an image and a sheet discharging unit 4 for stacking the scanned original are provided in a vertical relationship.
When a document is placed on the paper feed unit 3, a first lever member 5 that rotates counterclockwise due to the placed document and retracts from a sensor 19 described below is provided downstream of the sheet feeding unit 3. ing. Further, a pickup roller 6 for sending out the original is provided above the position of the leading end of the original in the paper feed unit 3. The pickup roller 6 has a separation normal rotation shaft 7.
, And rotational force is transmitted through the shaft 7.

[0005] On the downstream side of the pickup roller 6,
There is provided a separation forward roller 8 for separating the originals one by one and sending them out. The originals are separated by a separation reverse rotation roller 9 which presses against the separation normal rotation roller 8 and rotates in the opposite direction as shown in the figure. It is designed to be transported downstream. A space 10 for bending the original in a loop is provided downstream of the separation normal rotation roller 8, and further downstream of the space 10, the original conveyed from the separation normal rotation roller 8 is brought into contact with the space 10. A registration roller 11 for bending the original into a loop and a pressure roller 12 for pressing against the registration roller 11;
The document is configured to correct the skew of the document by bending the document in a loop, and to send the document downstream.

The leading end of a registration lever 13 for detecting a document sent into the space 10 projects into the space 10 on the upstream side of the registration roller 11. The registration lever 13 rotates clockwise to turn on the registration sensor 14.

The original sent out by the registration rollers 11 is sent onto a reading glass 15 of an image reading section B, and an optical unit disposed below the glass 15 while passing over the glass 15. (Not shown), the image is read continuously.

In the mode in which a document is fed from the document feeder A, the optical unit is not readable by the reading glass 15.
However, in the mode in which the document feeder A is rotated clockwise and the documents are set one by one on the glass 2, the document feeder A stops at a predetermined speed from the reading start position to the reading end position. By moving, the image of the document is read.

In the mode in which the document is fed from the document feeder A, the document whose image has been read is guided in the direction of the paper discharge section 4 and is discharged by a paper discharge roller 16 and a paper discharge roller 17 driven by the paper discharge roller 16. It is discharged to the paper tray 4. An end of a second lever member 18 for detecting that a document is being discharged is provided at a position having a predetermined positional relationship with the first lever member 5 in the vertical direction on the upstream side of the discharge roller 16. From the front end of the original conveyed in the direction of the paper discharge roller until the rear end passes, maintaining a state of clockwise rotation and turning off a sensor 19 described later. It has become.

The sensor 19 is constituted by a transmission type optical sensor shared by the first and second lever members 5 and 18,
The fact that the document is placed on the paper feed unit 3 and that the document is being discharged to the paper discharge unit 4 is detected based on the operation states of the two lever members 5 and 18.

Here, the length of the paper transport path from the transport start position to the transport end position of the document is set shorter than the minimum paper length. That is, before the trailing edge of the document comes out of contact with the first lever member 5,
The length is set so as to be in contact with the lever member 18. For example, assuming that the minimum sheet size is A4 size lateral feed, the length is set to 210 mm or less.

The upper portion of the sheet conveying device A is configured to be openable and closable by a rotation fulcrum 20 for taking out a document having a paper jam.

In the image reading apparatus constructed as described above, first, before the original is placed on the paper feed section 3, the first lever member 5 is in the state shown in FIG.
And the sensor 19 is turned off. However, when the document is placed on the paper feed tray 3, the first lever member 5 is rotated counterclockwise by the placed document 21 as shown in FIG. As a result, the sensor 19 is turned on, and the document is
Is detected. When the automatic document feed start button (ADF start button) is operated in this state, the motor M starts to rotate forward and the separated normal rotation shaft 7 descends to the document surface, and the pickup roller 6 attached to the leading end thereof
Is rotated in the direction of the arrow shown in the figure, so that several upper documents are sent out in the direction of the separation normal rotation roller 8. Then, only the uppermost document is separated by the separation forward roller 8 and sent out toward the registration roller 11.

The leading edge of the original sent out toward the registration roller 11 hits the registration lever 13 before contacting the registration roller 11, and the registration lever 13 is rotated clockwise. As a result, the registration sensor 14 turns on. Thereafter, the document abuts on the registration roller 11, but a control unit (not shown) rotates the motor M forward by a transport amount equivalent to a certain number of pulses after the registration sensor 14 is turned on, thereby bending the document in the space 10, The orientation of the document is corrected so that the document does not skew. Then, the motor M is switched to the reverse rotation state at a time when the posture of the document is corrected, and the registration roller 11 is rotated in the direction of the arrow shown in the figure. Thus, the original is conveyed toward the reading glass 15.

The optical unit positioned below the reading glass 15 starts rotating the registration roller 11 in the reverse direction.
The reading of the document image is started at the timing when the document is transported by the transport distance corresponding to the fixed pulse number. In this way, the image described on the document is continuously read following the conveyance speed of the registration roller 11.

Thereafter, the original is guided in the direction of the discharge roller 16, and the registration sensor 13 is turned on, and the registration roller 11 and the discharge roller 16 are moved by a distance equivalent to a predetermined number of pulses.
Is discharged onto the paper discharge tray 4 by rotating the.
The leading edge of the document hits the second lever member 18 while reaching the paper discharge tray 4, and the second lever member 18 is rotated clockwise. As a result, the rear end of the lever member 18 acts on the sensor 19 to turn off the sensor 19. Here, since the first lever member 5 is kept rotating counterclockwise while the document remains on the paper feed tray 3, the document that has been read is sent to the paper discharge tray 4. Each time, the second lever member 18 turns the sensor 19 on and off. That is, the sensor 19 is turned off while the document is being discharged while contacting the second lever member 18, and is turned on when the trailing end of the document comes off the second lever member 18. As described above, while the original remains on the paper feed tray 3, the sensor 19 functions as a paper ejection sensor for checking the paper ejection state of the original.

Attention is paid to the final read original. If the rear end of the final original comes off the first lever member 5 and then the leading end of the final original comes into contact with the second lever member 18, the sensor 19 Cannot be used as a paper ejection sensor. To solve this point, as described above, the length of the paper transport path from the original transport start position to the original transport end position is
The length is set shorter than the minimum paper length. That is,
The length of the original is set so that the rear end of the original comes into contact with the second lever member 18 before the rear end of the original comes out of contact with the first lever member 5. Therefore, after the leading end of the final document rotates the second lever member 18, the trailing end of the final document comes off the first lever member 5. As a result, the first lever member 5 acts on the sensor 19 even if the sensor 19 is turned off while the final document is being discharged and the rear end of the final document is further conveyed and the trailing end of the sensor is disengaged from the second lever member 18. As a result, the sensor 19 is maintained in the off state, and returns to the initial state in FIG.

If the sensor 19 is not turned off even if the original is conveyed a distance equivalent to a predetermined number of pulses after the rear end of the original has passed through the registration lever 13, if a paper jam occurs in the conveyance path to the paper discharge roller 16 (see FIG. This indicates that a jam has occurred or that the next document is not present in the paper feed tray 3, so that the document transport operation is stopped. When a paper jam occurs, the upper portion of the sheet conveying device A is rotated clockwise by a predetermined angle around the pivot 20 to open the document conveying path between the registration roller 11 and the pressing roller 12. Remove the original jammed in.

In the above-described sheet conveying apparatus, an upper guide (first guide means) for guiding a document is provided between the separation / reverse roller 9 and the registration roller 11. A lower guide is provided between the guides to guide a document conveyed therebetween. However, conventionally, as shown in a partial sectional view of FIG. The cover (cover means) 23 of the paper feeding unit is a shaft (rotating shaft) 20.
It can be opened and closed around the center. In addition, this shaft 20
Is a document conveying direction at the edge of a tangential plane contacting the document guide surface of the upper guide outside the upper guide (first guide means) and at the edge of the upper guide on the document conveying downstream side. Are provided in a region defined by an object orthogonal to the above. When the cover 23 is opened and closed, the upper guide 2
The upper guide 21 is extended to a sufficient length while taking care not to cause the lower guide 22 to interfere with the registration roller 11, and the lower guide 22 is formed in accordance with this, or as shown in FIG. A structure is used which extends to an upper portion beyond the position 12 to improve the document transportability.

[0020]

However, in the guide structure of FIG. 7, the angle of entry of the document into the lower guide 22 after passing through the space between the pressure roller 12 and the registration roller 11 is large, and the document There is a problem that the tip breakage and paper jam are likely to occur.

Although the guide structure shown in FIG. 8 has good transportability, even if the cover 23 is opened to remove a jammed document, the document remains sandwiched between the registration roller 11 and the pressure contact roller 12. Is difficult to remove.

Therefore, as shown in FIG.
Is extended as much as possible, and at the same time, the leading end is formed in an arc shape to reduce the entry angle of the document. In this structure, when the cover 23 is opened upward, the leading end of the upper guide 21 is It comes into contact with the outer peripheral surface of the registration roller 11 and cannot be opened.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sheet conveying apparatus in which the leading end of the sheet is hardly broken or the sheet is jammed, and even if the sheet jams, the sheet can be easily removed.

[0024]

According to the present invention, a first guide member movable to a guide position for guiding a sheet and a release position for opening a conveying path, and the first guide member are provided. A sheet conveying device including a second guide member disposed to face the device, a rotatable device cover that opens and closes at least a part of the device, and a first guide member attached to the device cover to swing the first guide member. Supporting means for freely supporting, urging means for urging one end of the first guide member in a direction away from the second guide member, and a guide position for urging the first guide member against the urging means The first guide member is released from the regulation of the regulating device by the opening operation of the device cover, and is oscillated in the direction away from the second guide member by the urging of the urging device. Then move to open position And it is characterized in Rukoto.

[0025]

[0026]

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. <Structure> FIG. 1 is a longitudinal sectional view showing an overall structure of an image reading apparatus in which a sheet conveying apparatus according to the present invention is integrated, FIG. 2 is a sectional view of a main part showing a state in which a cover member is closed, and FIG. FIG. 4 is a cross-sectional view of a main part in a state where the cover member is opened by about 5 degrees, and FIG. 4 is a cross-sectional view of a main part in a state where the cover member is further opened.

The sheet conveying apparatus A of this embodiment is mounted on an image reading section B.

Hereinafter, the configuration will be described. The same or corresponding parts as those of the conventional device are denoted by the same reference numerals, and the description thereof will be omitted.

In FIG. 1, a sheet conveying device A includes a first rotating member, for example, a pressure roller 12 and a second rotating member, for example, a registration roller 11 which are arranged opposite to each other for conveying a document.
A first guide unit such as an upper guide 21 and a second guide unit such as a curved guide 31 are arranged so that a document conveyed by the pressure roller 12 and the registration roller 11 is opposed to each other.
And the press roller 12
And the upper guide 21 are connected, and
The pressing roller 12 and the upper guide 21 are rotatable about the registration roller 11 and the curved guide 3
A cover means, for example, the cover 23 is provided to separate and approach the document feed path 1 to open and close the document feed path 42. Note that the shaft 20 is located outside the upper guide and at the edge of the upper guide on the document transport downstream side, and is perpendicular to the document transport direction on the normal line at the edge of the tangent plane contacting the document guide surface of the upper guide. It is provided in an area defined by the object.

The cover 23 is connected to the rotating shaft 2 via the stay 30.
It is rotatably supported at zero. The cover 23 is provided with support means such as a rotation shaft 24 via a bracket 32, and a holding means such as a lever 25 is rotatably attached to the rotation shaft 24. The pressure roller 12 is attached to one end of the lever 25.
Are pressed against the registration roller 11 with the cover 23 closed. Note that a roller 41 is pressed against the registration roller 11.

The upper guide 21 has a member 33 on its back.
So that the upper guide 21 is rotatably supported by the rotation shaft 24 via the member 33, and the distal end portion 26 is urged toward the pressing roller 12 displaced together with the cover 23. The tip of the member 33 is connected to the other end of the lever 25 by an urging means such as a connection spring 28, and the other end 27 is restricted by a restriction means such as a stopper 29 for restricting displacement by the connection spring 28.
Is engaged. In this case, the upper guide 21 is formed in an arc shape such that the leading end portion 26 has a small angle of entry of the document. When the cover 23 is opened, the distal end portion 26 comes into contact with the rotating shaft 12 </ b> A of the pressing roller 12, and is moved in the pressing direction of the pressing roller 12 urged by the connecting spring 28 in the direction of pressing against the registration roller 11. Also serves as an engaging portion for regulating the pressure. A lower guide 22 is provided at the end of the upper guide 21. <Operation> In the above configuration, when the cover 23 is closed as shown in FIG. 2, the pressing roller 12 is urged clockwise by the connection spring 28, and the outer peripheral surface thereof is
Is pressed against. Since the other end of the lever 25 is connected by a connecting spring 28 so as to pull on the tip of a member 33 erected substantially at the center of the upper guide 21, the tip 26 of the upper guide 21 is urged counterclockwise, The leading end 26 increases the gap between the registration roller 11 and the registration roller 11. At this time, the other end 27 of the upper guide 21 hits the bottom surface of the stopper 29, and the amount of rotation of the tip 26 in the counterclockwise direction is regulated. As a result, the upper guide 21 has its tip 2
6 is held so as to maintain a predetermined gap between the resist roller 6 and the registration roller 11.

As a result, the pressing roller 12 is pressed against the registration roller 11 by a force according to the resilience of the connecting spring 28, and the upper guide 21 has its tip end 26 to maximize the gap with the registration roller 11. Is held.

On the other hand, when the cover 23 is opened more than 5 degrees as shown in FIG. 3, the downward pressing force of the rotating shaft 24 is lost, so that the other end of the lever 25 and the tip of the member 33 are connected. The springs 28 attract each other. As a result, the lever 25 rotates clockwise about the rotation shaft 24 to maintain the pressure contact force between the pressure roller 12 and the registration roller 11, and the distal end portion 26 of the upper guide 21 rotates counterclockwise. And is displaced so as to retreat from the document transport path 42. At this time, the rotation shaft 12A of the pressing roller 12 comes into contact with the distal end portion 26 of the upper guide 21 and its rotation is restricted.

When the cover 23 is further opened as shown in FIG. 4, the tip of the upper guide 21 is displaced according to the displacement of the cover 23 in the opening direction while being kept displaced. That is, when the cover 23 is opened five times, the tip 2
6 retreats in the direction away from the lower guide 22, and is displaced upward in conjunction with the cover 23 in this retracted state. Therefore, even if the distal end portion 26 of the upper guide 21 is extended, the lower guide 2
2 and without colliding with the outer peripheral surface of the registration roller 11
The document transport path 42 can be opened. <Effect of Embodiment> As described above, in this embodiment, when the cover 23 is opened by a predetermined angle, the upper guide 21 retreats toward the pressing roller 12 side, and in this retracted state, the upper guide 21 is displaced in the opening direction of the cover 23. Therefore, even if the leading end 26 of the upper guide 21 is extended to reduce the angle of entry of the original, the original transport path 2 is opened without colliding with the lower guide 22 or the outer peripheral surface of the registration roller 11. Paper jam documents can be removed very easily.

Further, since the upper guide 21 is extended and the leading end is formed in an arc shape, the original can be fed in the direction of the glass 15 without causing the leading end of the original to be broken or jammed. <Modifications> (1) In the above embodiment, the upper guide 21 is the first guide unit and the curved guide 31 is the second guide unit. However, the upper guide 21 and the pressure roller 12 are the first guide unit and the curved guide. 31 and the registration roller 11 may be used as second guide means. (2) In the above embodiment, the upper guide 21 and the lever 25 are supported by the same rotating shaft 24, but they may be supported by different shafts. (3) In the above-described embodiment, the upper guide 21 and the lever 25 are connected and biased by the same connection spring 28.
The side may be urged by a separate spring or another elastic member, for example, like the first urging means, and the lever 25 like the second urging means.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an overall configuration of an image reading apparatus in which a sheet conveying device according to the present invention is integrated.

FIG. 2 is a cross-sectional view of a main part of the sheet conveying apparatus according to the present invention with a cover closed.

FIG. 3 is a cross-sectional view of a main part of the sheet conveying apparatus according to the present invention in a state where a cover is opened by about 5 degrees.

FIG. 4 is a cross-sectional view of a main part of the sheet conveying apparatus according to the present invention, with a cover opened at least five degrees.

FIG. 5 is a cross-sectional view illustrating an overall configuration of a conventional sheet conveying apparatus.

FIG. 6 is a cross-sectional view for explaining the operation of a conventional sheet conveying device.

FIG. 7 is a sectional view of a main part showing an example of a structure of a guide member in a conventional sheet conveying apparatus.

FIG. 8 is a main part sectional view showing another example of the structure of the guide member in the conventional sheet conveying apparatus.

FIG. 9 is a sectional view of a main part showing still another example of the structure of the guide member in the conventional sheet conveying apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Registration roller 12 Pressure contact roller 20 Rotating fulcrum 21 Upper guide 22 Lower guide 23 Cover 24 Rotating shaft 25 Lever 26 Tip of upper guide 27 The other end of upper guide 28 Connection spring 29 Stopper

Claims (4)

(57) [Scope of request for utility model registration] A guide position for guiding a sheet and a conveying path are defined.
A first guide member movable to an open position to be opened and
A second guide member disposed to face the first guide member
In a sheet conveying device comprising: A rotatable device that opens and closes at least a part of this device
Bar and A first guide member attached to the device cover;
Support means for swingably supporting the One end of the first guide member is connected to the second guide member.
Urging means for urging in a direction away from the The first guide member is pressed against the urging means by the guide.
Regulating means for regulating the position of the The first guide member is opened by opening the device cover.
Is released from the regulation of the regulating means, and
Swinging in the direction away from the second guide member by urging
And then moving to the open position.
Transport device. 2. The method according to claim 1, further comprising:
A transport roller disposed on the first guide member side
A pressure urged in a direction in which the pressure roller is
With a contact roller, The first guide rocked by the opening operation of the device cover.
One end of the pressure member prevents the pressing roller from being biased in the pressing direction.
The sheet conveying device according to claim 1, wherein
Place. 3. The urging means press-contacts the press roller.
3. The sheet according to claim 2, wherein the sheet is biased in the direction.
Transfer device. 4. The first guide member and the second guide
Is characterized by forming a curved conveying path.
The sheet conveying device according to claim 1, wherein: