JPH0624604A - Sheet material conveying device - Google Patents

Abstract

PURPOSE:To prevent a sheet material from dropping from a loading means and causing a conveying failure and a paper jam by controlling to change a conveying condition of a sheet material conveying means based on output of a sheet material thickness detection means. CONSTITUTION:In a control means 51, a recycle sensor 9 for detecting a cycle of documents, a document sensor 8 for detecting presence of the document, an after-register sensor 16 for detecting both end parts of the document, a paper thickness sensor 39 for detecting sheet thickness of the document and the like are respectively connected to respective input ports P0 to P6 while a various kinds of motors 61, 63, 66 and solenoids are respectively connected to respective output ports F0 to F5 When thickness of the document is not less than, for example, specified thickness, a drive motor 63 is decelerated to decelerate a drive roller and a paper discharge roller respectively so as to decrease discharge speed of the document. The document discharged from the paper discharge roller is prevented from dropping from a document, tray with excessive force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material conveying device for detecting the thickness of a sheet material to be conveyed and changing the conveying condition of the sheet material according to the thickness.

[0002]

2. Description of the Related Art As an example of a conventional sheet material conveying device,
FIG. 10 shows an outline of the circulation type automatic document feeder 101. The overall operation is as follows. A platen glass 103, which serves as a document reading position, is arranged on the upper surface of the main body of the copying machine 102 as an image forming apparatus.
Original D is automatically fed on top, and original D after reading
Is also automatically removed from the platen glass 103 by the circulating automatic document feeder 101, and
The next new original document D is set on the platen glass 103.

The circulating automatic document feeder 101 will be described in detail below. The document D has a shutter 106 at its front end.
The sheet is set on the original tray 105 so that it hits, the half-moon roller 110 is rotated, and the sheet is fed in the direction of arrow K1. The lowest document D is conveyed to the nip portion between the separation belt 112 and the paper feed roller 111, which is wound around the roller pair, and separated by one sheet. The separated document D is fed to the nip portion between the driving roller 113 and the registration roller 115. The original document D is then set on the platen glass 103 by the transport belt 117 that is wound around the drive roller 119, the driven roller 120, the rollers 121, 122, 123 and the like on the platen glass 103 on the upper surface of the apparatus main body. The set document D is exposed by a light source (not shown) to read an image, and then is conveyed along the discharge assisting guide 125 by the reverse rotation of the conveying belt 117, and further driven by the driving roller 113 and the driving first. Roller 126, drive second
The rollers 127 carry the upper surface of the flapper 129, and the paper is discharged onto the original tray 105 by the paper discharge rollers 130 and the paper discharge rollers 131.

When copying a document D having images on both the front and back sides, the document D is copied after the copying of one side is completed.
When the flapper 129 is switched, the sheet is set again on the platen glass 103 in a state of being turned upside down by the conveyor belt 117, and the image on the remaining surface is read.

The operation of each member and the operation of transporting the original D are controlled through the respective sensors arranged on the transport path of the original D. For example, the separation sensor S ₂ downstream of the separation belt 112 and the registration sensor S upstream of the registration roller 115.
₃ , reversing sensor S ₄ below the reversing roller, pair of discharge rollers 2
24 is an upstream paper discharge sensor or the like.

In the figure, 107 and 109 are sensors for detecting the final document on the document tray 105, 108 is a document detection sensor, and 116 is a post-registration sensor.

The document D is fed from the document tray 105 by the respective sensors and the transport members, further subjected to operations such as transport, stop (exposure), transport, and discharge, and then discharged onto the document tray 105 again. To be done.

[0008]

However, in the above-described circulating type automatic document feeder 101, the thickness of the document D changes because the document D is conveyed and discharged at a constant speed regardless of the thickness of the document D. However, in the case of being particularly thick, for example, the paper is likely to be ejected by the paper ejection roller 130 at a speed higher than necessary and fall from the document tray 105, may not be properly aligned even if it does not fall, or may cause a paper jam in the conveyance path. There was a risk of becoming.

Further, regarding the thickness of the sheet material such as the document D, there is a thickness range in which it can be satisfactorily transported. However, if the sheet material is too thick or too thin beyond this range, it is transported. This will cause defects and paper jams.

Therefore, according to the present invention, the discharged sheet material is changed by changing the conveying condition of the sheet material based on the thickness of the sheet material including the original document and the transfer sheet, that is, the sheet material to be conveyed. An object of the present invention is to provide a sheet material feeding device that does not drop from a stacking unit (original tray) or cause a paper jam in a transport path.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and is a conveying means for conveying a sheet material (D) and an object to be conveyed which is arranged in a sheet material conveying path. In the sheet material conveying device provided with the sheet thickness detecting means (32) for detecting the thickness of the sheet material (D), which is based on the output of the sheet thickness detecting means (32),
It has a control means (51) which changes the sheet material transportation conditions of the transportation means.

Further, the conveying means is a paper discharging means (30) for discharging the sheet material (D) to the stacking means (5) for receiving and aligning the sheet material (D), and the control means (51). ) Can control the sheet material discharging speed of the paper discharging means (30) based on the output of the sheet thickness detecting means (32).

Further, the control means (51), if the thickness of the sheet material (D) detected by the sheet thickness detection means (32) is out of a predetermined range, the conveying means (10, 11) is provided with a display member for stopping the conveyance of the sheet material (D) or notifying that the thickness of the sheet material (D) detected by the sheet thickness detecting means (32) is out of a predetermined range. You may do it.

In addition, the conveying means has a conveying member (11) capable of rotating in the forward and reverse directions, and the control means (51) is a sheet material (D) detected by the sheet thickness detecting means (32). The sheet material (D) can be discharged to the paper feed side by reversing the conveying member (11) on condition that the thickness is outside the predetermined range.

Furthermore, the sheet material conveying path has at least a main conveying path (P2) having a small curvature and a sub conveying path (P1) having a large curvature, and the control means (51) comprises:
The sub-conveyance path (P1) may be selected on condition that the thickness of the sheet material (D) detected by the sheet thickness detecting means (32) is out of a predetermined range.

[0016]

Based on the above construction, when the sheet material (D) is thick, for example, the discharging speed of the sheet material (D) is slowed, entry into the apparatus is prohibited, and the sheet material (D) can be conveyed. The normal thickness is displayed, such as indicating that the size exceeds the limit, reversing the paper feed roller (11) to eject the sheet material (D) to the paper feed side, and selecting the conveyance path (P1) having a large curvature. When the sheet material (D) of (1) is fed and the transportation condition is changed, it is possible to prevent the discharged sheet material (D) from dropping from the document tray (5) and jammed during transportation.

The reference numerals in parentheses are for reference to the drawings and do not limit the structure in any way.

[0018]

【Example】

<First Embodiment> An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a longitudinal section of a circulating type automatic document feeder 1 as an example of a sheet material conveying device according to the present invention. The circulating automatic document feeder 1 is arranged so as to cover the platen glass 3 on the upper surface of, for example, a copying machine 2 as an image forming apparatus, and has an original tray 5 at the upper part. The document tray 5 is attached so as to be inclined so that the direction in which the documents D are conveyed (the direction of arrow K1) is front-down, and a plurality of documents D are stacked on the upper surface. The document tray 5 is
Also, the document D discharged by the discharge roller 30 described later
Receive and collect. Reference numeral 6 denotes a shutter, which normally projects toward the transport path and regulates the position of the leading edge of the document D on the document tray 5 as shown in the figure. However, when the document D is fed, a shutter solenoid (not shown) is provided. To evacuate under the transport path and open the transport path. 7 is a recycle lever, which is placed on the document D by a recycle motor (not shown). The recycle lever 7 operates when the final document D on the document tray 5 is fed, and the recycle sensor 9 detects this operation and detects that the document D on the document tray 5 is gone. Reference numeral 8 denotes a document detection sensor composed of a transmissive optical sensor.
Detects that it is set above. Reference numeral 10 denotes a half-moon roller having a notch in a part of its circumferential portion, which is normally on standby immediately below the front end of the document D with the notch facing the lower surface of the lowest document D. When the half-moon roller 10 rotates, the half-moon roller 10 slides on the lower surface of the document D having the lowest circumferential portion, and feeds the document D to the downstream side. Reference numeral 11 denotes a paper feed roller that conveys the document D fed by the half-moon roller 10 further downstream. Reference numeral 12 denotes a separation belt that is in contact with the paper feed roller 11 and rotates in a direction opposite to the conveyance direction (arrow K1 direction) of the document D, and only the lowest one of the plurality of documents D is fed by the paper feed roller 11. Then, the remaining original D is prevented from being conveyed. Reference numeral 13 denotes a drive roller for nipping and conveying the document D with the registration roller 15 by being driven by a drive motor described later. A post-registration sensor 16 is a transmissive optical sensor and detects the presence or absence of the document D. The conveyor belt 17 located above the platen glass 3 is stretched around a belt driving roller 19 and a driven roller 20 paired with the belt driving roller 19, and is further brought into close contact with the platen glass 3 by belt pressing rollers 21, 22, and 23. The conveyor belt 17 includes a belt driving roller 19
The document D is carried in and set on the platen glass 3 by rotating in the normal direction and the reverse direction, and the document D set on the platen glass 3 is carried out. The discharge assisting stand 25 disposed below the belt drive roller 19 guides the leading edge of the document D when being conveyed out of the platen glass 3 and facilitates the delivery of the document D to the downstream side. 26,
Reference numeral 27 denotes a first driving roller which is pressed by the driving roller 13 and holds and conveys the document D with the driving roller 13,
It is the second driving. Reference numeral 29 denotes a flapper, which takes a solid line position shown in the drawing when the paper is discharged by a flapper solenoid (not shown), and when the document D is reversed, that is, the document D.
When inverting the front and back and resetting on the platen glass 3, the position of the dotted line is taken and the transport path is switched.
Reference numeral 30 is a paper discharge roller, and 31 is a paper discharge roller, which holds and conveys the document D, and discharges the document D onto the document tray 5 which also serves as a paper discharge tray.

Next, referring to FIG. 2, sheet thickness detecting means 3
The configuration of No. 2 will be described. The sheet thickness detecting means 32 is
As a whole, it is arranged above the paper feed roller 11 shown in FIG. The sheet thickness detecting means 32 has a sheet thickness detecting lever 33 bent in a hook shape, and the sheet thickness detecting lever 33 is supported by a lever shaft 35 of the bent portion so as to be swingable in a substantially vertical direction. One end of the sheet thickness detection lever 33 has a roller shaft 36 and a roller 3
7 is rotatably supported. The roller shaft 36 has an arrow R
The rollers 37 are arranged parallel to the axis of the paper feed roller 11 rotating in one direction, and therefore the roller 37 faces the paper feed roller 11 and sandwiches the document D between the paper feed roller 11 and rotates in the direction of arrow R2. A light shielding portion 38 is formed at the other end of the sheet thickness detecting lever 33, and a transmissive sheet thickness detecting sensor 39 is arranged within the swing range of the light shielding portion 38. The sheet thickness detection sensor (paper thickness sensor) 39 has a light projecting section and a light receiving section which are arranged so as to sandwich the light blocking section 38 (dotted line) moved to the raised position from both left and right sides, and the light projecting section to the light receiving section. Forms the optical path to. The sheet thickness detecting sensor 39 has an arrow K1 between the sheet feeding roller 11 and the sheet 37.
When the original D passing in the direction is thinner than a predetermined thickness (original D ₁ ), the light-shielding portion 38 does not block the optical path of the sheet thickness detection sensor 39 (solid line in FIG. 2), and therefore is turned off. On the other hand, when the original D is thicker than the predetermined thickness (original D ₂ )
In accordance with the rise of the roller 37, the light shielding portion 38 rises to block the optical path of the sheet thickness detecting sensor 39 (dotted line in FIG. 2), and the sheet thickness detecting sensor 39 is turned on. That is,
The sheet thickness detection unit 32 detects that the thickness of the document D exceeds a predetermined thickness by turning on the sheet thickness detection sensor 39.

Next, with reference to FIG. 3, the structure of the drive unit of the circulating automatic document feeder 1 will be described. In the figure, 61 is
It is a separation motor, and a separation motor gear 41 is attached to the output shaft of this separation motor 61. Then, the rotation of the separation motor 61 is transmitted to the half moon roller gear 42 and the drive roller gear 43 via the separation motor gear 41, and the half moon roller 10 and the paper feed roller 11 are rotationally driven. An idler gear 44 is further connected to the shaft of the paper feed roller 11, and the idler gear 44 rotates when the separation belt gear 4 rotates.
5 is transmitted to the separation belt 12 via the separation belt 12
Is driven to rotate in a direction opposite to the rotation of the paper feed roller 11. A half-moon flag 60 is attached to the shaft of the half-moon roller 10, and the cutout portion of the half-moon roller 10 is detected by the half-moon sensor 62 via the half-moon flag 60.

Reference numeral 63 is a drive motor, and this drive motor 6
A drive motor gear 46 is connected to the output shaft of No. 3. The rotation of the drive motor 63 is controlled by the drive motor gear 4
Drive roller gear 47, discharge roller gear 48
And the drive roller 13 and the paper discharge roller 30 are rotationally driven. On the output shaft of the drive motor 63, on the side opposite to the drive motor gear 46, a drive clock disk 64 having a plurality of slits arranged at equal intervals on the circumference is attached. In the vicinity of 64, a drive clock sensor 65, which is a transmissive optical sensor that detects the slit, is provided.

Reference numeral 66 is a belt motor, and a belt motor gear 49 is connected to the output shaft of the belt motor 66. The rotation of the belt motor 66 is transmitted to the belt driving roller 19 via the belt driving gear 50, and the conveyor belt 17 is rotated. On the output shaft of the belt motor 66 on the side opposite to the belt motor gear 49, the belt clock disk 6 having a plurality of slits arranged at equal intervals on the circumference.
A belt clock sensor 68, which is a transmissive optical sensor that detects the above-mentioned slits, is provided near the belt clock disk 67.

Next, the control circuit of the circulation type automatic document feeder 1 will be described with reference to FIG. The control circuit is a ROM,
It is mainly configured by a well-known one-chip microcomputer (hereinafter referred to as “MCOM”) 51 having a built-in RAM and the like, and the input ports P _{0 to} P ₆ of the MCOM 51 each detect the order of the document D. Recycle sensor 9, document detection sensor 8 for detecting the presence or absence of document D, half moon sensor 62 for detecting the cutout portion of half moon roller 10, rotation amount of drive motor 63, drive roller 13, and paper discharge roller 30.
Drive clock sensor 65 that counts the amount of movement of the belt, a rotation amount of the belt motor 66, a belt clock sensor 68 that counts the amount of movement of the conveyor belt 17, and the front and rear edges of the document D immediately after the drive roller 13. The post-registration sensor 16 and the sheet thickness detecting sensor 39 for detecting whether the sheet thickness of the document D is larger than a predetermined value are connected, and signals from them are input.

Further, the output ports F _{0 to} F ₅ are turned on and off by the recycle motor for rotating the recycle lever 7 and placing the original D on the manuscript roller 10 and the feed roller 10 via the drivers D _{0 to} D ₅ , respectively. ON / OFF operation of the separation motor 61 that controls the rotation of the paper roller 11 and the separation belt 12, ON / OFF operation of the drive motor 63 that controls the rotation of the drive roller 13, and belt motor 66 that controls the movement amount of the transport belt 17. The flapper 29 is switched depending on whether the document D is turned on or off, the shutter solenoid that opens the paper feed port is turned on or off, and the document D is reversed or discharged.
Output signals are output to perform ON / OFF operations of the flapper solenoid that switches the transport path.

Next, taking a copy operation when _two originals D ₁ and D ₂ are set in the circulation type automatic document feeder ₁ , the control method thereof will be described with reference to FIGS. 5, 6, 7 and 8.
Will be described in detail. However, it is assumed that the document D ₁ is a general paper that is thinner than a predetermined thickness (the maximum thickness of the document that can be conveyed by the apparatus 1 without any trouble), and the document D ₂ is a thick paper that is thicker than the predetermined thickness. 5 to 7 are flowcharts of control,
FIG. 8 shows control signals of the separation motor 61, the shutter solenoid, the drive motor 63, the belt motor 66, and the post-registration sensor 16 when controlled according to the control flows of FIGS.

The original detection sensor 8 is used to detect the originals D ₁ and D.
_{When 2} is detected, when the start signal is sent from the copying machine 2, the feeding operation of the circulating automatic document feeder 1 is started (S1). Separation motor 61 turns on (S
2) The originals D ₁ and D ₂ are rotated by the rotation of the half-moon roller 10.
Is abutted against the shutter 6. When the shutter solenoid is turned on (S3), the shutter 6 retracts to the outside of the conveyance path and the conveyance path is opened. The rotation of the half-moon roller 10 feeds the document D ₁ to the downstream side. At this time, in the document D ₂ , the separation belt 12 is rotating in the direction opposite to the paper feeding roller 11, and the document D ₂ is stronger than the force conveyed by the document D ₁ .
It is not fed because the force returned by the separation belt 12 is strong.

Here, the signal from the sheet thickness detecting means 32 of FIG. 2 provided on the sheet feeding roller 11 is confirmed (S).
4). In the case of the document D ₁ , the following control is taken. Further, when the separation motor 61 is continuously rotated, the document D ₁ is pushed at the rear end while the leading end is abutted against the nip portion between the drive roller 13 and the registration roller 15, thus forming a loop.
The clock of the separation motor 61 is counted and stopped so as to form a predetermined amount of loop (S7). Immediately after that, when the drive motor 63 is turned on (S8), the document D ₁
Is transported. The belt motor 66 is turned on before the leading edge of the document D ₁ reaches the conveyor belt 17 (S9), and the document D ₁ is conveyed by the conveyor belt 17 pressed onto the platen glass 3 via the belt pressing rollers 21, 22, 23. It is transported on the platen glass 3. When the document D ₁ passes through the post-registration sensor 16 (S10), the drive motor 63 is turned off and the drive roller 13 is stopped (S11). The separation motor 61 is turned on (S12), the second document D ₂ is conveyed, and abutted against the nip portion between the drive roller 13 and the registration roller 15, and at the same time, the second document is detected in the document detection mode (S13). The thickness of D ₂ is detected. When a suitable loop is formed in the same manner as the _first document D ₁ , the separation motor 61 is turned off (S14), and the second document D ₂ is stopped. Then, after the trailing edge of the document D ₁ moving on the transport belt 17 passes through the post-registration sensor 16, the document D ₁ is transported halfway until the trailing end reaches a predetermined position on the platen glass 3. Stop the belt motor 66 (S1
5) Then, the feeding is completed (S16). After this, copy machine 2
Will scan.

Next, the operation for discharging the _first original D _{1 and} the operation for feeding the _second original D ₂ are started (S31 in FIG. 6). Reversing the belt motor 66 (S32), 1 sheet of the document D ₁
Is conveyed from the platen glass 3 to the paper discharge path. At this time, the leading end of the document D _{1 in} the traveling direction is not
Before entering the nip portion with the roller 26, the drive motor 63 is turned on (S33), and the feeding of the _second document D ₂ is started.
The belt motor 66 is rotated in the forward direction before the leading edge of the _second document D _{2 in} the traveling direction reaches the conveyor belt 17 (S3).
4). After that, the first document D ₁ is ejected, and the second document D ₂ is fed, causing the documents to pass each other. The first document D ₁ is nipped and conveyed by the drive roller 13, the drive first roller 26, and the drive second roller 27. Further, the document D ₁ is nipped and conveyed between the paper discharge roller 30 and the paper discharge roller 31. Two
It is confirmed whether or not the first document D ₂ has passed through the post-registration sensor 16 (S35), and when it is detected that the document D ₁ has passed, the paper thickness flag of the _first document D ₁ is confirmed (S36). For plain paper (original D ₁ ), the speed is reduced to the paper discharge speed v ₁ obtained by the drive motor 63 (S5).
0). On the other hand, when the flag is 1, that is, when the paper is thick (original D ₂ ), the discharge speed is reduced to V ₂ where v ₁ > v ₂ (S51). After that, the shutter 6 is turned off (S37),
The belt motor 66 is turned off (S38).

The trailing edge of the _first document D ₁ is the discharge roller 30.
After the sheet has been conveyed so as to pass through the nip between the sheet discharge roller 31 and the sheet discharge roller 31, the drive motor 63 is stopped (S39). Thus, the discharge of the _first document D ₁ and the feeding of the _second document D ₂ are completed (S40).

Next, a method of detecting the sheet thickness according to the present invention will be described with reference to FIG. As described above with reference to FIG. 5, when the thick paper detection mode (S4) is entered, the subroutine of FIG. 7 is processed (S61). Sheet thickness detection sensor 3
If the signal from 9 is detected (S62) and this is off,
The paper thickness flag is set to 0 (S63). On the other hand, when the signal of the sheet thickness detection sensor 39 is ON, the sheet thickness flag is set to 1
(S64). Thus, the paper thickness detection mode is ended (S65), and the process returns to the routine of FIG. It is to be noted that FIG. 8A shows timings of ON / OFF of the sheet feeding operation and the sheet discharging operation of each motor shown in the flowcharts of FIGS.
It is (b).

As described above, when the thickness of the document D exceeds the predetermined thickness (for example, the document D ₂ ), the drive motor 63 is decelerated via the sheet document detection sensor 39, so that the drive roller 13 and the discharge roller 13 are ejected. By decelerating the paper roller 30 and slowing down the discharge speed of the document D, the document D discharged from the paper discharge roller 30 may drop from the document tray 5 due to excessive force, or may be disturbed on the document tray 5. Discharged paper is often prevented from being stacked. <Embodiment 2> FIG. 9 shows an example in which the sheet material conveying apparatus according to the present invention is applied to a sorter.

Reference numeral 201 denotes a main body of the copying machine, and a paper output port thereof is connected to a sorter 202.
The copying machine (sheet material) D, which is copied by the copying machine main body 201, is collected by the discharging roller pair 203 and collected from the main body 201.

Reference numeral 204 denotes a first conveying roller, which is the main body 2
The copy paper D discharged from 01 is conveyed. The peripheral speed is
It is set to be slightly faster than the paper discharge roller 203. 20
Reference numeral 9 denotes a transport path switching flapper, which is a straight transport path when not sorting, and S when sorting.
The copy paper D is guided to the conveyance path 210 formed in a letter shape. 20
A non-sorting roller pair 7 discharges the paper onto the bin 208 when not sorting. 205 is an intermediate roller pair and 206 is a sort roller pair.
One roller pair holds and conveys the copy paper D at the time of sorting.

In the above-mentioned structure, the information from the sheet thickness detecting sensor 39 provided in the paper feeding section of the copying machine main body is used.
In the thick paper mode, the speed is reduced immediately before the copy paper is discharged into the air from the non-sort roller pair 207 and the sort roller pair 206. As a result, good stackability can be obtained for thick paper as well as for thin paper. <Embodiment 3> Next, an embodiment will be described in which the original (sheet material) D is too thick or too thin to be conveyed with respect to a predetermined thickness, or is too thin. In the sheet thickness detecting means 32 of the present embodiment, unlike the sheet of the first embodiment provided with one sheet thickness detecting sensor 39, as shown in FIG. 12, two sheet thickness detecting sensors 39a, 39a, 39
b. The sheet thickness detection sensors 39a and 39b are positioned (solid line) of the light shielding portion 38 of the sheet thickness detection lever 33 when the document D ₁ having a thickness within a predetermined range is passing.
, Above and below. The upper sheet thickness detection sensor 39a has its optical path blocked by the light-shielding portion 38 that has risen when a document D ₂ (dotted line) thicker than a predetermined range has passed, while the lower sheet thickness detection sensor 39b has been cut off.
The light path is blocked by the light-shielding portion 38 that descends when the document D ₃ (one-dot chain line) thinner than the predetermined thickness passes, so that the sheet thickness detecting means 32 causes the thickness of the document D to deviate from the predetermined range. To detect that FIG.
The control circuit of this embodiment is shown in FIG. The difference from the control circuit of the first embodiment shown in FIG. 4 is that the sheet thickness detection sensors (paper thickness detection sensors) 39a and 39b are connected to the MCOM 51.

Next, the sheet thickness detecting sensor 3 according to the present invention.
9A or the sheet thickness detecting sensor 39b is turned on, that is, the processing when the thickness of the fed document D is outside the range of the thickness that is acceptable for conveyance, FIG.
The details will be described with reference to FIGS. In the following description, the same components as those shown in each drawing of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 14, a sheet material detection sensor 39
When a (or 39b) is turned on, that is, when an abnormality is detected, abnormality processing is performed (S17).

First, the separation motor 61 is stopped and the conveyance of the document D is stopped. Next, the document D fed to a display unit (not shown) provided in, for example, the operation unit of the copying machine 2 shown in FIG. 11 has a thickness that cannot be conveyed by the circulation type automatic document feeder 1. In addition, the user is informed and warned that the document D being fed is pulled out and taken out. The user opens the cover shown at 52 in FIG.
To the side opposite to the transport direction. At this time, since the nip between the paper feed roller 11 and the separation belt 12 is released in association with the opening of the cover 81, the document D can be easily removed. Note that the separation motor 61, the shutter solenoid, the drive motor 63, the belt motor 66, and the post-registration sensor 16 in the present embodiment are shown in FIG.
It is illustrated in (a) and (b).

In the above-described embodiment, the example in which the lowermost original D of the bundle of originals set on the original tray 5 is fed is shown. However, in the case of feeding from the uppermost original D, the sheet is fed. When the sheet thickness detection sensor 39a (or 39b) detects that the thickness of the document D is outside the predetermined range, for example, the paper feed roller 11 is rotated in the reverse direction and the document D is fed in the normal conveyance direction ( The sheet may be discharged in the direction opposite to the arrow K1 direction), that is, toward the document tray 5. <Embodiment 4> An example in which the present invention is applied to a sheet feeding device of a copying machine will be described with reference to FIG. Reference numeral 301 denotes a copying machine, which will be described by taking processing in the manual feed mode as an example. When copying paper is set on the bypass tray 302, the paper detection sensor 3
03 detects this, and enters the manual feed mode. The manual paper feed roller 304 starts to rotate. A sheet thickness detection sensor 305 similar to that shown in FIG. 12 is arranged on the manual feed roller. When the sheet thickness detection sensor 305 detects that the sheet thickness is out of the transportable range, the sheet feeding roller 304 immediately stops and stops the transportation. A display unit (not shown) arranged in the copying machine 301 displays that the paper thickness cannot be conveyed and that the copy paper is removed. <Embodiment 5> Next, an example of selecting a conveyance path having a large curvature as the conveyance path when the document D is thick in the circulating automatic document feeder will be described.

In FIG. 18, reference numeral 71 is a document tray for setting the document D to be copied face up. Reference numeral 72 denotes a half-moon roller that abuts the document D set on the document tray 71 against the shutter 73. When the shutter 73 is retracted below the conveyance path by a shutter solenoid (not shown), the document D is fed by the half-moon roller 72 to the paper feed roller 74.
Sent to. Reference numeral 75 denotes a separation belt, which rotates in the opposite direction to the feeding direction of the document D, so that when a plurality of documents D are set on the document tray 71, only the lowest document D is fed. To do. A pair of registration rollers 76 abuts the document D fed by the paper feed roller 74 against the nip, and further rotates the paper feed roller 74 to loop the document D and correct the inclination of the document D. After the loop is formed, the original D is pinched and conveyed by being rotated, and the original D is brought into close contact with the platen glass 95 by the conveyor belt 77.

The length of the document D in the traveling direction is determined by the document tray 7
When the length is equal to or less than the stackable length of 1, the conveyor belt 77 rotates in the direction of the solid line in the figure, and the first discharge roller pair 92, the second discharge roller pair 93, and the third discharge roller pair 94 The document is discharged onto the document tray 71. On the other hand, when the length of the document D in the traveling direction exceeds the length that can be stacked on the document tray 1,
By placing the document on the document auxiliary tray 71 ', it becomes impossible to pass the above-mentioned transport path, and therefore the following transport path is passed. The same applies to the reverse mode of the document D.

Reference numeral 78 is a large roller, and rollers 79, 80
Is pressed, and the fed document D is pinched and conveyed by the reverse rotation of the conveyance belt 77 (in the direction of the dotted arrow in the figure). Reference numeral 81 denotes a deflector, which discharges the document D when it is in the position shown by the solid line in the figure, and when it is in the position shown by the dotted line in the diagram
Invert. A pair of paper discharge rollers 82 discharges the document D onto the document tray 71.

As the sheet thickness detecting means 32 used in this embodiment, the one shown in FIG. 2 is used. The same applies to the operation. That is, in the case of a general document whose document D is thinner than a predetermined thickness (document D ₁ ), the sheet thickness detection lever 33 is in the position shown by the solid line, and the sheet thickness detection sensor 39 is in the off state. . On the other hand, when the thickness of the original document D is thicker than the predetermined thickness (original document D ₂ ), the sheet thickness detection lever 33 takes the position of the dotted line, the sheet thickness detection sensor 39 is turned on, and the original document D is Detects that it is thick.

Next, the paper conveying method according to the thickness of the document D will be described in detail below. FIG. 19 is a basic flow chart of document transportation at the time of one-sided copying when the document D can be stacked on the document tray 71, and FIG. 20 shows a paper discharge path (transport path) according to the flow of FIG. When a signal to start feeding is input from the image forming apparatus (S1), the feeding operation is performed to detect the thickness of the document D (S2). The document D is set on the platen glass 95, and the image surface of the document D of the image forming apparatus is scanned (S3). Since the thickness of the document D is detected at the time of feeding by the sheet thickness detection sensor 39 described above, the information is read (S4), and if the thickness is normal (general paper), it is shown in FIG. The sheet is passed through the second sheet discharge path (main conveyance path) P2 shown. On the other hand, if it is thick, the first paper discharge path (sub-transport path) P1 in FIG. 20 is discharged. As a result, the conventional method is all second
If the user mistakenly feeds a thick original D because the paper is being ejected through the paper ejection path P2, the conveyance force obtained by the conveyance belt 77 is smaller than the conveyance force obtained by the conveyance belt 77 in the conveyance path with a small curvature at the portion A in FIG. , The sum of the frictional force generated in the A portion and the frictional force generated between the platen glass 31 becomes larger, and the original D
In some cases, the paper cannot be conveyed, or it takes more than a predetermined time to pass through the paper to judge a paper jam.

However, by passing the thick original D having a large curvature as in this embodiment through the conveying path P2, the original D can be smoothly discharged.

[0046]

As described above, according to the present invention,
By the sheet thickness detecting means for detecting the thickness of the sheet material,
When it is detected that the thickness of the sheet material is not good for conveyance, for example, the paper discharge speed is reduced, the conveyance is stopped,
By notifying that the sheet material is unsuitable, discharging the sheet material in the direction opposite to the normal transport direction, selecting a transport path with a large curvature, etc., the sheet material falls from the stacking means such as the document tray, It is possible to effectively prevent a conveyance failure or a paper jam.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an outline of a circulating automatic document feeder according to a first embodiment.

FIG. 2 is an explanatory view of the operation of the sheet thickness detecting means.

FIG. 3 is a top development view showing the structure of a drive unit in the same manner.

FIG. 4 is a block diagram showing a control circuit of the same.

FIG. 5 is a flow chart showing the feeding of originals.

FIG. 6 is a flow chart showing the discharge of a document.

FIG. 7 is a flowchart for similarly detecting a document thickness.

8A and 8B are diagrams showing ON / OFF timings of control signals in the same manner.

FIG. 9 is a vertical sectional view showing a sorter according to a second embodiment.

FIG. 10 is a vertical cross-sectional view of a conventional circulation type automatic document feeder.

FIG. 11 is a vertical sectional view of a circulation type automatic document feeder according to a third embodiment.

FIG. 12 is an explanatory view of the operation of the sheet thickness detecting means.

FIG. 13 is a block diagram showing a control circuit of the same.

FIG. 14 is a flow chart showing the feeding of originals.

FIG. 15 is a flowchart showing the discharge of a document.

16 (a) and 16 (b) are the same for turning on the control signal,
The figure which shows the timing of OFF.

FIG. 17 is a vertical cross-sectional view showing the sheet feeding device of the copying machine according to the fourth embodiment.

FIG. 18 is a vertical sectional view of a circulating type automatic document feeder according to a fifth embodiment.

FIG. 19 is a flowchart showing selection of a paper discharge furnace.

FIG. 20 is an operation explanatory diagram of the same.

[Explanation of reference numerals] 1 sheet material conveying device (circulation type automatic document feeder) 5 stacking means (original tray) 11 conveying means (paper feeding roller) 30 paper discharging means (paper discharging roller) 32 sheet thickness detecting means 51 control means (Microcomputer) D Sheet material (original, copy paper) P1 Sub-conveyance path (first ejection path) P2 Main conveyance path (second ejection path)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Hasegawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Katsuaki Hirai 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (6)

[Claims] 1. A sheet material conveying apparatus comprising: a conveying means for conveying a sheet material; and a sheet thickness detecting means arranged in a sheet material conveying path for detecting the thickness of a sheet material to be conveyed. A sheet material conveying apparatus comprising: a control means for changing a sheet material conveying condition of the conveying means based on an output of the sheet thickness detecting means. 2. The conveying means is a paper discharging means for discharging the sheet material to a stacking means for receiving and aligning the sheet material, and the control means is based on the output of the sheet thickness detecting means. The sheet material conveying device according to claim 1, wherein the sheet material discharging speed of the sheet discharging means is controlled. 3. The control means stops the conveyance of the sheet material by the conveying means on condition that the thickness of the sheet material detected by the sheet thickness detection means is outside a predetermined range. The sheet material conveying device according to claim 1. 4. The sheet material according to claim 1, further comprising a display member for notifying that the thickness of the sheet material detected by the sheet thickness detecting means is out of a predetermined range. Transport device. 5. The carrying means has a carrying member capable of rotating in the forward and reverse directions, and the control means provides that the thickness of the sheet material detected by the sheet thickness detecting means is outside a predetermined range. ,
The sheet material conveying device according to claim 1, wherein the conveying member is reversed to discharge the sheet material to a sheet feeding side. 6. The sheet material conveying path has at least a main conveying path having a small curvature and a sub-conveying path having a large curvature, and the thickness of the sheet material detected by the sheet thickness detecting means is outside a predetermined range. The sheet material conveying device according to claim 1, wherein the sub-conveying path is selected on condition that there is such a condition.