JPH0466432A - Sheet feeding device - Google Patents

Abstract

PURPOSE:To improve separating performance in an automatic manscript feeding device by providing a separating member with plural separate faces different in the coefficient of friction, and changing the separate face on an altering command for the abutting position of the separating member and also separating pressure according to the separare face. CONSTITUTION:A separating member is composed of separate faces, 6a-6d, different in the coefficient of friction. The kind of a manuscript designated on a manual knob 39 is selected on the kind of the manuscript P to be used to operate the knob 39. The separate faces 6a-6d complying with the kind of the manuscript P therefore attain an abutting position, and the separate feeding of the manuscript P is executed. When the knob 39 is operated to rotate a separate roller shaft 7, an eccentric cam 60 also rotates at the same time. The rotation of the eccentric cam changes the acting force of a tension spring 65 to a pressing member 61 alters, and separating pressure corresponding to the selected separate face acts onto a feed roller 2 to improve separating performance.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial field of application The present invention is capable of separating sheets due to the difference in friction coefficient between a feeding member that feeds the sheet and a separating member that contacts this feeding member with a predetermined separation pressure. The present invention relates to a sheet feeding device that separates and conveys sheets, and more particularly relates to a sheet feeding device that has a separation member having separation surfaces having at least two or more different R friction coefficients.

(Old Prior Art FIG. 18 shows an example of a conventional friction separation type sheet feeding device of this type.

In the figure, on the downstream side of a C-I-YU loading table (original table) 10 on which a plurality of sheets of originals P are set, there are
A notched circular calling roller 12 fixed to the support shaft 11
The calling roller 12 has a large diameter portion extending from the plate 13 to the lower guy 1. A sheet presser 17 whose base is pivotally connected to an upper kite plate 16 by a shaft 15 is in pressure contact with the calling roller 12, and a sheet presser 17 is placed between the sheet presser 17 and the upper guide plate 16 on the side of the calling roller 12. A compression spring 19 is disposed to bias the.

On the downstream side of the pick-up roller 12, there is disposed a feeding roller 2 which is fixed to a spindle 3 and rotates in the direction of an arrow 5 by an unillustrated drive source to feed the document P. Drive roller 20a and driven roller 2 rotating in the direction of the arrow
A pair of conveyance rollers 20 consisting of 0b is provided. The separation pad 21 whose free end is in contact with the feeding roller 2 and the base of the leaf spring on its lower surface are fixed to a support member 23 provided on the main body cover 22. The base is supported by the shaft 25
The free end of the press plate 26, which is pivotally connected to the support shaft member 23, is in contact with the separation pad 21, and the press plate 2
Reference numeral 6 presses the separation pad 21 against the feeding roller 2 by the elasticity of a separation spring 29 consisting of a compression spring provided between a fixing member 27 provided on the main body cover 22 and a pressing plate 26.

Here, the friction coefficient of the feeding roller 2 with respect to the original P is set to be larger than the friction coefficient between the originals P, and the friction coefficient of the separation pad 21 with respect to the feeding roller 2 is set to be smaller than the friction coefficient between the originals P. has been done. When the calling roller 12, the feeding roller 2, the pair of conveying rollers 20, etc. are rotated with a plurality of documents P set on the sheet stacking table 10, most of the documents P are regulated by the sheet presser 17 and are moved to the lower side. The document P is conveyed to the feeding roller 2. The transported document P is transferred between the feeding roller 2 and the separation bat 21.
The sheets are separated and fed one by one due to the difference in the coefficient of friction between the two sheets, and are further transported in the direction of arrow 30 by a pair of transport rollers 20.

(C) Problems to be Solved by the Invention However, in the conventional sheet feeding device described above, the separation pad 21 for separating the document P has one friction coefficient selected and determined through repeated experiments, etc. Since it is made up of two members, it is difficult for thin paper or thick paper to pass through it, so the paper is biased towards one side. In addition, the range of types of sheets fed is narrow overall, and some sheets may not be fed.

In particular, when using the sheet feeding device as a document feeding device, there is no universal separation pad 21 for all types of documents, and it is difficult to select and test the friction coefficient of the separation pad 21. It required a lot of effort. Also,
The feeding performance of a sheet feeding device is greatly influenced by differences in the environment in which the sheet feeding device is used, and there are currently no conditions that satisfy all conditions. The most common complaint was that it was a sheet feeding device that fed sheets as original documents.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sheet feeding device in which a separation member having a plurality of separation surfaces with different coefficients of friction is provided, and sheets are separated by a separation surface suitable for the sheets being fed. That is.

(d) Means for Solving the Problems The present invention has been made in view of the above-mentioned circumstances, and is illustrated with reference to, for example, FIGS. , a feeding member (2) that is driven in a direction to feed a plurality of sheets one by one; and the feeding member (2).
a separating member (6) that separates the sheet (P) by contacting the separating member (6) and having separating surfaces (6a to 6d) having at least two or more different coefficients of friction (μa to μd); 6) command means (39, 53) for setting the contact position of
), and the separation surfaces (6a to 6d) of the separation member (6) are moved to predetermined separation surfaces (6a to 6d) according to the command from the command means (39, 53).
6d), and when the separation member (6) is changed by the separation member change means (4), the separation member (6) is changed to the separation pressure corresponding to this separation member (6). ) for changing the separation pressure changing means (60, 61
).

(e) Effect Based on the above configuration, when the feeding member (2) rotates while the sheet (P) is inserted between the feeding member (2) and the separating member (6), the separating member (6) If the material (P) is separated, the paper is fed as is, and if the material (P) is not separated, the separating member (6) separates the sheet CP using separation surfaces (6a to 6d) having other coefficients of friction (μa to μd). ). Thereafter, the same operation is performed to separate the sheet (P) using the separation surface (6) having a friction coefficient suitable for the sheet (P) to be fed.This separation surface (6a to 6d)
1 separation member (6) in response to changes in feeding roller (2)
The separation pressure brought into contact with the sheet (P) is varied by the separation pressure changing means (60, 61), whereby the feeding action on the sheet (P) is set by both the friction coefficient of the separation member (6) and the separation pressure. As a result, sheets (P) of a wide variety of paper qualities can be stably fed.

Note that the above-mentioned symbols in parentheses are shown for reference to the drawings, and do not limit the configuration of the present invention in any way.

B) Embodiment Hereinafter, an embodiment of an automatic document feeder (hereinafter referred to as ADF) as a sheet feeding device of the present invention will be described based on the drawings. Components having the same functions as those shown in FIG. 18 are denoted by the same reference numerals, and their explanation will be omitted.

1 and 2 show an apparatus f (ADF) that feeds a document P in the form of a sheet. In the figure, a support shaft 3 to which a feeding roller (feeding member) 2 is fixed is pivotally supported by a pair of side plates 31 and 32 via bearings, respectively, as shown in FIG. A gear 35 connected to a sheet conveyance motor 33 (see FIG. 13) serving as a drive source is fixed to one extending end of the support shaft 3.

A separating member 6 fixed to a separating roller shaft 7 is in pressure contact with the feeding roller 2 as will be described later. They are each pivotally supported via. As shown in FIG. 3, the separation member 6 has at least two (four in this embodiment) different friction coefficients μ on the circumferential surface of the base roller 6A.
It consists of separated surfaces 68 to 6d having sizes a to μd fixed to each other. A pair of support members 34a fixed to the inner surfaces of the side plates 31 and 32 are each provided with a leaf spring 34b that presses the upper part of the separation roller shaft 7, and the elasticity of the leaf spring 34b causes the separation member 6 to be obtains separation pressure for the feed roller 2.

The respective friction coefficients μa to μd of the separation surfaces 68 to 6d are μa
〉μb〉μC〉μd. In particular, the last friction coefficient μd is selected to be a low friction coefficient such that μd≦μp with respect to the friction coefficient μp between documents P. For example, a member such as Mylar is used as the separation surface 6d having a low coefficient of friction μd. This separating surface 6d is not capable of separating double-fed originals P, and is particularly used when the originals P are manually fed one by one.

Furthermore, if μ is the friction coefficient of the feeding roller 2 with respect to the original P, then μm>μa, and the above μC is μC>μp(
(friction coefficient between originals). The separation member 6 is rotated by a command means to be described later, and one of separation surfaces 68 to 6d having a predetermined coefficient of friction is selected and pressed against the feeding roller 2.

The end of the separation roller shaft 7 extending from the side plate 32 (
At the right end in the figure) is a position detection plate 36 (see Figure 9).
a gear 37 that is integrally formed with the , and a manual operation knob (command means) that rotates the separation member 6 as described later.
39 are each fixed. The above-mentioned arrow 30 is for detecting the separation surfaces 68 to 6d that are pressurized by the feeding roller 2. On the outer peripheral surface 39a of this knob 39,
As shown in FIG. 5, information corresponding to the friction coefficients of the separation surfaces 68 to 6d of the separation member 6 in pressure contact with the feeding roller 2 is written.

That is, characters 40a to 40d representing the type of document P to be separated by the selected separation planes 68 to 6d are displayed 40.
It is displayed as shown in . Above characters 40a~
40d corresponds to each separation surface 68 to 6d of the separation member 6, and for example, when feeding a document P made of plain paper, the corresponding separation surface 6 b fJ (f & At the same time as it comes into pressure contact with the feeding roller 2, characters 40b are displayed on the display section 40.

The knob 39 can be rotated from the outside of a window 22a provided in the main body cover 22 as shown in FIG.
0d is visible from the display unit 40. moreover,
A plurality of click recesses 39b are formed in the circumferential surface 39a of the knob 39, as shown in FIG. By engaging the free end of the knob 42, the selectively rotated position of the knob 39 is held.

The opposite extending end of the separation roller shaft 7 is attached to a bearing 45 via a one-way rotation clutch 43, and this bearing 45 is attached to a support member 4 fixed to the side plate 31.
5 so that it can be moved downward within an appropriate range. Due to the action of the one-way rotation clutch 43, the separating member 6 rotates only in the direction of arrow 9 in FIG. 1, and is prevented from rotating in the opposite direction. Note that when the separation member 6 rotates in the direction of arrow 9, the separation surface 6a has a high friction coefficient, and the separation surface 6b has a low friction coefficient.
The separation surfaces 6a, 6b, 6c, and 6d are arranged so as to come into pressure contact with the feeding roller 2 in the order of 6c and 6d.

As shown in FIG. 2, a gear 49 is fixed to the end of the support shaft 11 to which the above-mentioned pick-up roller 12 is fixed.
(see Figure 3). As shown in FIG. 1, on the upstream side of the calling roller 12, a sheet presence/absence sensor 5 is provided for detecting the presence or absence of a document P on the sheet stacking table 10.
This sheet presence/absence sensor 50 is connected to a sensor lever 50a that is rotated by the document P and a sensor lever 50a that is rotated by the document P.
It consists of a photointerrupter 50b that turns on and off.

Further, on the downstream side of the feeding roller 2, a sensor lever 51a is provided.
A sheet feeding sensor 51 including a photointerrupter 51b and a photointerrupter 51b is provided. This sheet feeding sensor 51 detects the original P fed by the feeding roller 2, and determines whether or not the separation of the original P by the separating surfaces 68 to 6d which are currently in pressure contact has been properly performed. This detects whether the separation surfaces 6a to 6d being pressed are suitable for the document P being fed.

The separating surfaces 6a to 6d to be brought into pressure contact with the feeding roller 2 can be set by manually operating the knob 39 as described above, but this setting can also be done by using the keyboard shown in FIGS. 7 and 8. In the figure, a keyboard 53 for setting separation surfaces 6a to 6d to be used is provided on the negative side of a printer (image forming device) to which an ADF (automatic document feeder) as a sheet feeding device is applied. or is arranged. As shown in FIG. 8, this keyboard 53 has operation buttons 56 (56a to 56a to
56d) and a display section 57 that displays the operated items as characters 578 to 57d.

This display section 57 displays the set operation button 5.
6a to 56d may be illuminated, or the corresponding characters 57a to 57d on the display section 57 may be illuminated from the back side to make them visible. Furthermore, when the operation button 56 is operated, the status of the separation surfaces 68 to 6d may be displayed using the LCD display section 55 as shown in FIG.

When setting the separating surface using the keyhole 1-53, a driving force is required to drive the separating member 6 in response to the operated operation button 56, and this driving force is applied to the separating member 6.
The rotation of the motor 59 is transmitted to the gear 37 (see FIG. 2) which is integrated with the motor 59.

In addition, in order to detect the separation surfaces 6a to 6d that are in pressure contact with the feeding roller 2, a plurality of separation surface detection sensors 52 (52a to 52d) are arranged at predetermined positions as shown in FIG. 9(b). This separation surface detection sensor 52 is connected to the position 1 detection plate 3.
This is detected by a flag 36a provided at 6. The relationship between the positions of the separation surface detection sensors 52a to 52d and the separation surfaces 68 to 6d is shown in FIG. 9(b).
They are arranged correspondingly as shown in (c).

A command means 4 for setting the abutting position of the separating member 6 is mounted together with the above-mentioned knob 39 and the arrow 5 shown in FIG.

FIG. 11 shows an a-hazard that changes the separation pressure of the separation member 6.

In the same figure (a), an eccentric cam 60 is fixed to the separation port-ra shaft 7 which is integrated with the separation member 6.
A pressure member 61 is pressed against the upper part of 0 by the elasticity of a tension spring whose one end is locked to a pin 63. This pressure member 61 is pivotally supported by a support shaft 62, and its upper end is connected to a solenoid 67 via a connecting member 66.

When the solenoid 67 is in the OFF state, the separating member 6 is in pressure contact with the feeding roller 2 due to the separating pressure due to the elasticity of the bow tension spring 65, and the rotation of the separating member 6 causes the separation front surfaces 6a to 6 to
When d is switched as described later, the separation pressure against the feed roller 2 is also changed by the action of the eccentric cam 60.

When changing the separation surfaces 68 to 6d of the separation member 6,
Since separation pressure is acting on both the separation member 6 and the feeding roller 2, the solenoids 1-67 are operated at the time of switching so that no load is applied to the driving means such as a motor when switching the separation surfaces 68-6d. The separation pressure is released to facilitate rotation of the separation member 6.

Alternatively, as shown in FIG. 11(b), an Archimedes cam 71 may be provided on the separation roller shaft 7, and a roller 61a provided on the pressure member 61 may be brought into pressure contact with the Archimedes cam 71 to change the separation pressure. As the Archimedes cam 71 rotates together with the separation member 6, the elasticity of the tension spring 65 changes, so that the rotation position T of the separation member 6, that is, the switching of the pressure contact of the separation surfaces 6a to 6d, changes the separation member 6. Separation pressure is changed.

The above-mentioned position detection plate 36, one-way rotation clutch 43, sheet feeding sensor 51, dividing surface detection sensor 52, timer 69, CPU 70 (see FIG. 13), etc., are used to control the road separation surface of the separation member 6 by the command means 4. Separation member changing means 4 for switching 6a to 6d to the front by a predetermined amount is mounted together.

Next, the operation of the automatic document feeder configured as described above will be explained with reference to the flowcharts shown in each of the above-mentioned figures, FIGS. 14 and 15. In addition, Figure 14 is the manuscript P.
FIG. 15 shows a flowchart for the case where the originals P are loaded together and when the originals P are loaded together. First, the same type loading mode will be explained. When a plurality of documents P are placed on the sheet stacking table 10 and inserted, the sheet presence/absence sensor 50 detects this. When a start operation is performed here, the sheet conveyance motor 33 shown in FIG.
etc., each starts rotating, and one or more sheets of the original P are fed to the feeding roller 2.

Before separating the documents P, the separation member 6 is normally in a state in which the separation surface 6a having the largest friction coefficient is in pressure contact with the feeding roller 2 (SL), and the state in which the separation surface 6a is in pressure contact is returned to the original position. (Bohm position). Among the documents P to be fed, there are thin documents that are difficult to separate and feed as documents P that are suitable for separation by the separation surface 6a having a large friction coefficient.
Next are normal manuscripts, thick manuscripts, etc.

Referring to FIG. 10, the separation operation of the original P will be explained. The document P located between the feeding roller 2 and the separating member 6 is separated by the feeding roller 2 and the separating member 6, which rotate in the directions of the arrows, respectively, in response to a paper feeding command by operating the start button, and the rotational speed of the feeding roller 2 increases. Move at the same speed as the arrow 3, or move at a speed slightly slower than the rotation speed if there is a slip.
When the sheet moves in the 0 direction and is detected by the sheet feeding sensor 51 and is further conveyed by the pair of conveying rollers 20, the rotation of the feeding roller 2 is stopped.

At this point, the document P that is being fed with a slip or the feeding roller 2
The sheet feeding sensor 51 is inserted from the pressure contact position between the separating member 6 and the separating member 6.
If the time required for the document P to reach the sensor lever 51a is t, then if the document P takes longer than that, the separation surface 6a of the separation member 6 that is in pressure contact with the feeding roller 2 will not be suitable for separating the document P. Become.

In this case, the paper feed is stopped and the separation member 6 is rotated in the direction of arrow 9 by the motor 59, and this rotation is stopped by detection by the separation surface detection sensor 52. Here,
The same separation action is repeated by rotating the feeding roller 2 again. In this way, by sequentially changing the separation surfaces 68 to 6d, if the document P is fed, that is fine, but if the document P is not fed, a warning (alarm sound, lamp lighting) is issued and the LCD display 57 etc. will be displayed.

As described above, when the separation surfaces 68 to 6d are automatically switched and set using the time t as a parameter and paper feeding is finished, the separation member 6 must be returned to its original position.

To explain the above operation along FIG. 14, an attempt is made to separate the document P on the separation surface 6a (side a) of the separation member 6 by the rotation of the feeding roller 2 (S2), and the document P is separated. If so, the process continues as it is and the paper is fed until 5IO) without paper, and the process ends (311).

Further, if separation by the separation surface 6a is not performed in (S2), the separation member 6 rotates due to the rotation of the sheet conveyance motor 33, and the separation surface 6b comes into pressure contact with the feeding roller 2 (S3). is detected by the separation surface detection sensor 52b of FIG. 9(b), the separation member 6 is stopped, and the separation member 6 is displayed on the display section 57 or the display section 55 or the like.

When the document P is separated by the separation surface 6b in (S4), the process continues to feed paper until it runs out of paper (5IO), and ends when it runs out of paper (311). (S4
), the separating member 6 is rotated in the same manner as described in -F (S2), and the next separating surface 6C comes into pressure contact with the feeding roller 2 (S5), and the document P is separated by the separating surface 6C. (S6). If separation can be performed, the paper is fed up to 510) without any paper.

If separation is not possible in the above (S6), in this case, the separation member 6 will not automatically rotate and the paper feed will stop (S7).
). This non-separable state is indicated by an alarm or the like, and when displayed on the display section 55 (see FIG. 5), characters 55d1 are displayed. In this state, the operator operates the operation button 56d for single-sheet originals (see FIG. 8), thereby rotating the separating member 6 and bringing the separating surface 6d into pressure contact with the feeding roller 2 (S8). . Then, in the single original mode, as shown in FIG. 6(d), the I-CD character 55d
will be displayed.

Here, the single-sheet mode refers to a part of the separation member 6 (separation surface 6
d) is made of a material with a low friction coefficient, such as Teflon, and means that one document P can be fed without fail. The single-sheet mode is a mode that is facilitated when the original P is not fed even after changing the friction surface (separation surface) of the separation member 6, and is set at the end of switching between the separation surfaces 6a to 6d. mode. Separation surface 6 as above
Switching between a to 6d is achieved by sequentially arranging and rotating the friction coefficients from the one with the largest coefficient of friction to the one with the smallest coefficient of friction, and it is possible to feed paper by automatically performing this switching.

In this one-sheet mode, the document P is inserted and fed one by one into the feeding roller 2 by the operator's manual operation (S9).
. During manual paper feeding, the friction coefficient μd between the separating surface 6d and the original P is set to be smaller than the friction coefficient μp between the originals P, so if multiple originals P are inserted into the cage, The document P continues to be fed in duplicate.

In other words, the separation surface 6d is set to have a coefficient of friction small enough to allow manual paper feeding, making it easy to feed one sheet at a time.

Furthermore, since the document P used is generally plain paper, the separation member 6b can be set by operating the knob 39 or the keyboard 53 in advance before starting paper feeding. In the separation process, the separation surface 6a is omitted and the separation action is started using the separation surface 6b (5th surface), thereby saving working time.

Next, the document P is separated using each of the separation members 6 (Sl
l) When the process is finished, it is checked whether there is any key force on the keyboard 53 (S12). If there is key human power, the separation member 6 returns to its original position (home position) and starts separation operation from (Sl) by the separation surface 6a. (
In S12), if there is a key input, it is checked whether the input is the separation plane 6b (plane 5). If the input is 5 sides, the process returns to (S3) and the separation of the original P by the separation surface 6b is started, and if the input is not 5 sides, the process returns to (S5) and the separation of the original P by the separation surface 6c is started. .

FIG. 15 shows a flowchart of e) mixed loading mode in which each document P has different properties. In the figure, the sequential switching of the separation surfaces 68 to 6d when the document P cannot be separated at the start of paper feeding is the same as in the case of the same type loading mode in FIG. 13, so a description thereof will be omitted.

The difference between this mixed loading mode and the same type loading mode described above is that the originals are
If separation is being performed, one sheet of document P is fed (81
4), the presence or absence of the document P is checked (S15) and the settings are changed. If there is a manuscript P in (S15), be sure to return to the original position! After returning to (SL) and repeating the same process again, only one sheet is fed. When the document P continues to be fed and the document P runs out (Sll), the process ends, and the separating member 6 returns to its original position and stops.

By feeding the original P in this way, the original P
Sheet loading table 10 with a mix of paper types or different types
Even if the document is set to 1, the setting of the separation member 6 of the ADF changes accordingly, so documents P having different properties can be set with confidence.

In the case of feeding the above-mentioned mixed documents P, operate the operation button 56 of the keyboard 53 shown in FIG.
It is also possible to predetermine the initial position of , and in this case, the separation member 6 returns to the above-determined position of the separation surface. As a result, when feeding paper, the separating action of the separating member 6 does not have to start from thin paper, but can start from plain paper original P or thick paper original P, skipping the previous stage. Able to perform work efficiently.

In addition, when the paper quality of the original P changes and the separation surface of the separation member 6 is changed as described above, the separation pressure suitable for the separation surface to be used is adjusted using the separation pressure switching means as explained in FIG. 11. It is also possible to change them at the same time.

FIG. 16 and FIG. 17 show the second sheet feeding device of the present invention.
An example of this is shown.

In this embodiment, instead of the rotatable separation member 6 in the above-described embodiment, a plurality of pressure members 72 and separation bats 80a to 80 with different coefficients of friction are provided.
0c is used.

In the figure, a plurality of V-shaped pressure members 72 whose bases are pivotally supported on a support shaft 73 are biased clockwise in the figure by tension springs each having one end latched to a shaft 79. . The lower edge of the upper arm of each pressure member 72 is connected to a plurality of eccentric cams 7 each fixed to a cam 76.
5a to 75c, respectively. Each pressure member 72
Separation pads 80a to 80c are provided on the free ends of the feeding roller 2, and are selectively or combinedly pressed against and separated from the circumferential surface of the feeding roller 2.
are each fixed. In this embodiment as well, the command means for press-contacting the separation pads 80a to 80c is the same as in the previous embodiment, and the conversion means for switching the pressure-contact separation pads is one, driven by the motor 59 connected to the camshaft 76. or some separation pads 80 (80a~
80c) are brought into contact with the feeding roller 2 in descending order of friction coefficient, or documents P of a wide range of paper qualities are fed by being separated by Ill.

(G) As described in detail, according to the present invention, the separation member for separating sheets 1 to 1 is provided with a plurality of separation surfaces having different coefficients of friction to correspond to the paper quality of the sheets to be fed. By separating the sheet materials using a separated separation surface, it is possible to handle the feeding of various types of sheets, and when the separation surface changes, the split pressure or separation pressure of the separation member against the feeding roller is reduced. By being changed by the changing means, the separation and feeding force of the separating surface against the sheet can be set over a wide range, making it possible to stably feed sheets of various paper qualities.

[Brief explanation of the drawing]

FIG. 1 is a vertical side view of a sheet feeding device in which an embodiment of the present invention is applied to an automatic document feeding device, FIG. 2 is a developed plan view, and FIG. 3 (a) is a vertical side view of a separating member. 3(b) is a front view, FIG. 3(c) is a developed view showing another example of the separating member, and FIG. 4(b) is a plan view, FIG. 5 is a plan view showing the display section 40 provided on the knob, FIG. 6 is a plan view of the display section when operating the keyboard, and FIG. 7 is a plan view of the display section 40 provided on the knob. FIG. 8 is an enlarged plan view of the keyboard, FIG. 9(a) is a vertical cross-sectional side view of the position detection plate and the position detection plate, and FIG. 9(b) is the same. A front view, FIG. 9(c) is a diagram of the positional relationship of the separation member with respect to the separation surface detection sensor, FIG. 10 is an operational view of the device in FIG. 1, and FIG. 11(a) is a vertical cross-sectional side view of the separation pressure release mechanism. 11(b) is a side view showing another example of the separation pressure release mechanism, FIG. 12 is a timing chart of rotation of the paper feed roller and sheet detection after paper feeding, and FIG. 13 is a control of the present invention. 14 is a flowchart when sheets of the same type are loaded, FIG. 15 is a flowchart when sheets are mixedly loaded, and FIG. 16 is a longitudinal side view of a shift feeding device showing a second embodiment of the present invention. Figure 17 is also a developed plan view,
FIG. 18 is a longitudinal sectional side view showing an example of a conventional feeding device to the sea 1. P... Sheet (original) t... Time from the start of sheet feeding until it is detected 2... Feeding roller (feeding member) 4... Separation member changing means, 6.
...Separation member, 6a to 6d...Separation surface 33...
・Sheet conveyance motor 37...Gear 39...Knob, 39.53...Command means, 40...Display section
40a to 40d... Display characters 43... One-way rotation clutch (clutch member), 50... Sheet presence/absence sensor 51... Sheet feeding sensor, 52...
- Separation surface detection sensor 53...Keyboard, 55
a to 55d...Display characters 56...Operation buttons 57a to 57d...Display characters 59...
Motor 60.61...Separation pressure release means, 70...C
PU, 72...pressure member (separation member) 75a~
75c...Cam 80a-80c...Separation bat.

Claims (1)

[Claims] 1. A feeding member that is driven in a direction to feed a set of multiple sheets one by one, and a member that comes into contact with the feeding member to separate the sheets, and has at least two or more different coefficients of friction. a separation member having a separation surface, a command means for setting a contact position of the separation member, a separation member changing means for switching the separation surface of the separation member to a predetermined separation surface according to a command from the command means, and the separation member A sheet feeding apparatus comprising: separation pressure changing means for changing the separation pressure of the separation member to a separation pressure corresponding to the separation member when the separation member is changed by the change means.