JPH04159933A - Paper feeder - Google Patents

Abstract

PURPOSE:To make sure the draw-out of paper sheets with a transport roller by providing a paper feed-out roller on a stocker at the position where the distance from a transport roller arranged downstream of a paper separation means is shorter than the overall length of paper. CONSTITUTION:At the intermediate part and right end part of a stocker 10 on which paper sheets are stacked, feed rollers are arranged with a specified interval. At a paper feed passage opened at the right end of a stocker 10, paper separation means 13 (rollers 15, 16) and a paper feed roller 14 are provided in order. The distance between the roller 14 and the roller 11 located at the right end is made shorter than the overall length of smallest paper sheets 23. With the arrangement, feeding can be made by the roller 11 until the foremost end of paper sheets 23 reaches the roller 14 after passing over the separation means 13, and even if the roller 11 is stopped thereafter, sure pulling out can be made by the roller 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is applicable to industrial applications such as copying machines, printers, facsimiles,
The present invention relates to a paper feeding device that separates and feeds a large number of stacked sheets of paper one by one in an office machine such as a document reading device.

Conventional technology For example, as described in Japanese Utility Model Application Publication No. 1-121032, when paper sheets stacked in a stocker are sent out by a delivery roller (pickup roller), and a plurality of the delivered paper sheets overlap. There is a paper feeding device in which paper sheets are separated by a paper separation means consisting of a friction member such as a feed roller and a reverse roller, and further the paper is fed to a desired position by a conveyance roller.

Problems to be Solved by the Invention In general, the feed roller is maintained in a stopped state after passing the paper sheet from the stocker to the feed roller of the paper sheet separation means, and after that, the paper sheet is transferred downstream by the feed roller of the paper sheet separation means. The receiver is passed to the conveyor roller. The outer circumferential surfaces of these rollers, such as the delivery roller, feed roller, and conveyance roller, are made of a material with a relatively high coefficient of friction in order to feed paper sheets using frictional force. Therefore, if the feed roller is stopped at the time when the paper sheet has been transferred to the paper sheet separation means, the rear end of the paper sheet will be subjected to a large resistance by the feed roller. Moreover, the paper sheets are also subjected to resistance from the friction member of the paper sheet separation means. For this reason, the paper sheet separating means lacks the force to pull out the paper sheets, and the conveying roller slips against the paper sheets, resulting in the paper sheets not being sent to a predetermined position, or
Sometimes no paper leaves are sent at all. Furthermore, in order to prevent the resistance against the paper sheets on the stocker from increasing due to the increased contact pressure between the feed roller and the paper sheets, there are problems such as the amount of paper sheets loaded on the stocker is limited. .

Means for Solving the Problems The invention according to claim 1 provides a stocker in which paper sheets are placed in a stacked state, a paper feed passage whose entrance is opened toward the tip of the stocker, and feed rollers facing each other. a sheet separating means having a friction member and disposed in the sheet feeding path; a conveying roller disposed downstream of the sheet separating means in the sheet feeding path; and a feed roller that is placed at a position separated from the sheet by a distance shorter than the total length of the sheet and comes into contact with the sheet on the stocker.

According to a second aspect of the present invention, in the first aspect, a half-moon-shaped delivery roller having a partially circular portion on the outer periphery is used.

The invention according to claim 3 is the invention according to claim 2, further comprising a position detection means for detecting the rotational position of the half-moon-shaped delivery roller, and a drive time of the delivery roller during the first paper feeding operation based on a detection signal of the position detection means. A drive means for extending the length is provided.

According to a fourth aspect of the present invention, in the second or third aspect, a low friction member is provided that protrudes from the half-moon-shaped cutout portion of the delivery roller to the upper part of the bottom surface of the stocker.

According to a fifth aspect of the present invention, in the second, third, or fourth aspect, a low-friction member is provided in the half-circle portion of the half-moon-shaped delivery roller.

The invention according to claim 6 is the invention according to claim 1, 2, 3.4 or 5, wherein a paper sheet presser is provided on the upper part of the feed roller that contacts the lowest layer of sheets stacked on the stocker so as to be movable up and down. An expanding concave portion is formed on the upper guide surface of the passage, and is located upstream of the sheet separating means and expands toward the entrance of the sheet feeding passage.

The invention of claim 1 allows the paper sheets in the stocker to be sent out by the delivery roller until the leading edge of the paper sheet passes the paper separation means and reaches the conveyance roller. However, the paper sheet can be reliably pulled out to a predetermined position by the conveyance roller.

According to the second aspect of the invention, by stopping the delivery roller with its inlet portion facing the paper sheet, the resistance of the delivery roller against the paper sheet being pulled out from the stocker can be reduced. It becomes possible to promote the prevention of slips or non-feeding, and along with this,
Since the resistance exerted on the sheets from the feed roller can be reduced, the amount of sheets loaded on the stocker can be increased and the frequency of replenishing the stocker with sheets can be reduced.

In the third aspect of the invention, the paper sheets set in the stocker are located in front of the paper sheet separation means, and when the -th sheet of paper is sent out, the second and subsequent sheets are separated by frictional resistance between the sheets. In consideration of the approach to the leaf separation means, the drive means extends the drive time of the feed roller during the first paper feeding operation based on the detection signal of the position detection means that detects the rotational position of the feed roller. It is possible to solve the problem of insufficient amount of paper sheets being fed out by the feeding roller during paper operation.

According to the fourth aspect of the invention, when the feeding roller is stopped with the feeding section facing the paper, the paper can be supported by the low-friction member, so that the resistance to the paper that is pulled out from the stocker by the conveyance roller is reduced. This can effectively reduce the amount of paper slippage or non-feeding of paper sheets.

The invention according to claim 5 is such that when the feeding part is opposed to the paper sheet and the delivery roller is stopped, when the delivery roller is rotated to send out the next paper sheet, the length of the paper sheet to be used is short. Even if the trailing edge of the paper sheet may be kicked by the edge of the feed-out roller's entry section, the low-friction member provided inside the entry section can slide against the paper sheet.
It is possible to prevent the trailing edge of the paper from being folded or damaged, and also to prevent the stacking state of the paper on the stocker from collapsing due to folding or damage to the trailing edge of the paper.

According to the sixth aspect of the invention, the paper sheets in the stocker can be fed out by the feed roller until the leading edge of the paper sheet passes the paper sheet separation means and reaches the conveyance roller, and then the feed roller is stopped. Even if the paper sheet is pulled out to the specified position by the conveyance roller,
Moreover, since an expanding recess that expands upward is formed at the entrance of the paper feed path, even when a large number of sheets are stacked in the stocker, the upper layer of sheets will not come into contact with the stepped part of the expanding recess. , it is possible to approach only the paper sheets below the middle part to the paper sheet separation means side, and therefore it is possible to avoid the phenomenon of paper sheets clogging near the entrance of the paper feed path, and also to prevent the paper sheets on the stocker from getting stuck near the entrance of the paper feed path. As the number of sheets decreases, the sheet presser can push down the sheets from the expansion recess toward the delivery roller and allow them to advance toward the sheet separation means.

Example An embodiment of the present invention will be described based on the drawings.

As shown in FIG. 7, a photoreceptor 2 and a fixing roller 3 are rotatably provided along a linear sheet conveyance path l extending from direction A to direction B. As shown in FIG. A separating claw 4a is rotatably provided on the downstream side of the fixing roller 3 to switch the conveying direction of the fixed paper sheet to the B direction or the downward C direction. The sheet conveying path 4 extending from the separating claw 4a in the direction C is bent into a U-shape, and the middle part and thereafter are parallel to the sheet conveying path 1. Conveyance rollers 5 and 6 that are driven in a counterclockwise direction and a belt conveyor 7 that is driven in a counterclockwise direction are arranged. Pinch rollers 8 and 9 are pressed against the conveyance rollers 5 and 6 so as to be able to come into contact with and separate from them. Furthermore, a horizontal stocker 10 is provided below the intermediate portion of the sheet conveying path 4. Feeding rollers 11 that are driven clockwise are arranged at a predetermined interval below the intermediate portion and the right end portion of the stocker 10, and feed rollers 11 that connect the right end of the stocker 10 and the sheet transport path 1. A path 12 is provided to be curved in the direction of the arrow, and a sheet separating means 13 and a conveying roller 14 are arranged in this sheet feeding path 12. The sheet separating means 13 is composed of a feed roller 15 and a reverse roller 16 which is a friction member that resiliently contacts the feed roller 15. A sheet presser 18 that rotates together with a shaft 17 is provided above the feed roller 11 located on the right end side of the stocker 10 . Furthermore, a movable plate 19 is held reciprocally along the bottom surface of the stocker 10, and a part of an annular wire 21 driven by a step motor 2o is fixed to this movable plate 19.

A home position sensor 22 for optically detecting the moving plate 19 is arranged within the moving range of the moving plate 19. 23 is a paper leaf.

The shaft 24 of the conveying roller 6 is provided with a clamp roller (not shown) whose outer periphery includes a claw that grips the leading edge of the sheet 23 conveyed along the sheet conveying path 4. It is rotatably provided. When the double-sided copy mode is selected, this clamp roller grips the leading edge of the paper sheet 23 passing through the paper sheet conveyance path 4 with its claw and moves clockwise 180 degrees.
The claw is released from the sheet 23 and is driven 180 degrees clockwise to receive the next sheet 23. Therefore, the filter paper 23 that is guided into the paper transport path 1 with the printed side facing upward is turned into an S-shape while passing through the paper transport path 4, and is sent to the stocker 1o with the printed side facing upward. . When the composite copy mode in which copies are made multiple times on the same surface is selected, the function of the clamp roller is stopped, so the paper sheet 23 passing through the paper sheet transport path 4 is transferred to the transport roller 5.
, 6 and a belt conveyor 7, the paper is turned into a U-shape and sent to the stocker 10 with the printed surface facing downward.

The feed roller 11 located at the right end of the stocker 10 is placed at a position where it is separated from the transport roller 14 by a distance shorter than the entire length of the sheet 23, which is the shortest distance away from the conveyance roller 14. As shown in FIG.
2 is formed by arranging an upper guide plate 26 and a lower guide plate 27, which are vertically movably held by a shaft 25 and facing each other with a predetermined interval. On the upper guide surface 28 of the paper feed path, that is, on the lower surface of the upper guide plate 26, there is an expansion plate located upstream of the paper sheet separating means 13 and expanding toward the entrance of the paper feed path 12. An open recess 29 is formed, and the depth of the expanded recess 29 is about 30'' to 60'' toward the downstream side with respect to the vertical plane.
A step portion 30 having an inclination angle θ (see FIGS. 8 and 9) is formed. Furthermore, a paper sheet detector 31 located below the transport roller 14 is arranged in the paper feed path 12 .

The feed roller 11 has a cylindrical hub 11a and a half-moon-shaped rubber roller l having a cutout portion 11b on a part of the outer periphery.
It is formed by fixedly fitting the lc. The hub lla is formed of a low-friction member, and a circular flange lid that protrudes above the bottom surface of the stocker 10 from a circular notch 11b is integrally formed at one end of the hub lla. A low friction member lie is fixed. A plurality of such feed-out rollers 11 are fixedly fitted to each of two feed-out roller shafts 32 arranged in parallel at a predetermined interval, and a second As shown in the figure, timing pulleys 34 connected to each other by a timing belt 33 are fixed. At least one of the feed roller shafts 32 has a gear 36 with a built-in one-way clutch 35, a positioning cam 39 having a recess 38 on the outer periphery to be engaged with the roller 37, and a transmission type photoelectric detector 40. A slit disk 42 having opposing slits 41 on its outer periphery is fixed.

The photoelectric detector 4o and the slit disk 42 form a position detecting means 43 for detecting the rotational position of the feed roller 11.

As shown in FIG. 4, the roller 37 is rotatably held at the tip of a leaf spring 44 and biased toward the positioning cam 39. Further, the gear 36 fixed to one of the feed roller shafts 32 that rotates together with the feed roller 11 is connected to a drive gear 47 driven by a motor via gears 45, 46 and an electromagnetic clutch 49.

As shown in FIG. 6, the electromagnetic clutch 49 has a gear 49a meshed with the drive gear 47 on the drive side, and a driven side is directly connected to the feed roller shaft 48. A one-way clutch 52 is built into one of the bearings 50 and 51 that support the feed roller shaft 48. The feed roller shaft 48 is connected to the feed roller 15 via a one-way clutch 1.5a, and a gear 54 is fixed thereto. A gear 55 and a gear 56, which are meshed with the gear 54, are fixed to a transmission shaft 53 provided parallel to the feed roller shaft 48.
A reverse roller shaft 58 to which a gear 57 that meshes with is fixed.
The reverse roller 16 is connected to the reverse roller 16 via a torque limiter 59.

Furthermore, the shaft 1 rotates integrally with the sheet presser 18.
An arm 60 is fixed to one end of 7.

As shown in FIG. 5, one end of this arm 60 is biased counterclockwise by a spring 61 held by the upper guide plate 26. As shown in FIG. Further, a swinging lever 65 whose one end is connected to the plunger 63 of the solenoid 62 via a link 64 is rotatably held by a support shaft 66, and one end of this swinging lever 65 is held by the upper guide plate 26. The protrusion 68 is biased counterclockwise by a spring 67 and contacts the other end of the swing lever 65.
It is set to 0. Here, the tensile force of the spring 67 is determined so as to prevent the counterclockwise rotational movement of the arm 60 due to the biasing force of the spring 61. Therefore, when the solenoid 62 is energized, the swing lever 6
5 is rotated clockwise against the urging force of the spring 67, and the arm 60 is rotated counterclockwise together with the shaft 17 and the sheet presser 18. That is, the paper sheet presser 18 presses the paper sheets 23 on the stocker 10. Solenoid 6
2, the swing lever 65 is rotated counterclockwise while forcefully returning the arm 60 clockwise due to the biasing force of the spring 67.

In such a configuration, the photoreceptor 2 is charged by a charger (not shown), and the charged portion is exposed to light by an optical unit (not shown) to form an electrostatic latent image. The image is developed by a developing device (not shown) and an image is formed on the outer periphery of the photoreceptor 2.

This image is transferred to the paper sheet 23 during the process of transporting the paper sheet 23 along the paper sheet transport path l, and is fixed by the fixing roller 3.

When the double-sided copy mode is selected, the separating claw 4a is raised and the fixed paper sheet 23 is moved toward the paper sheet transport path 4 in the direction of arrow C.
The sheet 23 is conveyed to the stocker 1o by the conveyor rollers 5, 6 and the belt conveyor 7. In this double-sided copy mode, as described above, the leading edge of the paper sheet 23 is gripped by the clamp roller, which is arranged on the same axis as the conveyance roller 6 and driven intermittently every 180 degrees, so that the paper sheet 23 is The sheets 23 are inverted to form an S shape and stacked on the stocker 10 with the printed side facing upward. Therefore, stocker 1
In a state in which a zero sheet 23 is supplied to the sheet transport path l via the sheet feed path 12, the previously printed surface is directed downward.

When the composite copy mode is selected, the function of the clamp roller is stopped, so the sheet 2 passing through the sheet transport path 4
3 is U by transport rollers 5, 6 and belt conveyor 7.
The direction is changed to the letter shape and the printing side is facing down to the stocker 10.
It is sent to. Therefore, when the paper sheets 23 in the stocker 1o are supplied to the paper sheet transport path 1 via the paper feed path 12, the previously printed surface is directed upward.

In FIG. 7, the step motor 20 rotates the wire 21 and moves the moving plate 19 to the right, thereby pressing the stacked sheets 23 to a reference position on the right side of the stocker 10.

Subsequently, the moving plate 19 is returned to its home position by rotating the step motor 20 in the reverse direction. This position is detected by the home position sensor 22.

Next, the paper feeding operation from the stocker 10 will be described in detail.

First, as mentioned above, the paper sheet presser 18 presses the stocker 1.
Press the paper sheet 23 above 0. In this state, the feed roller shaft 48 is driven by turning on the electromagnetic clutch 49 with the drive gear 47 rotated by the motor, and the rotation of the feed roller shaft 48 is controlled by the gears 46, 45.
6 and the feed roller shaft 32.
1. As a result, paper sheet 2 on stocker lo
3 are sent to the bottom layer in order.

Further, the rotation transmitted to the feed roller shaft 48 is transmitted to the reverse roller shaft 58 via the gear 54.55, the transmission shaft 53, and the gear 56.57, and the feed roller 15 and reverse roller 16 are rotated clockwise. Driven. As a result, in FIG. 1, when a plurality of paper sheets 23 are sent out between the feed roller 15 and the reverse roller 16, the friction coefficient between the feed roller 15 and the paper sheets 23 and the reverse roller 16 Since the friction coefficient between the paper sheet 23 and the paper sheet 23 is larger than the friction coefficient between the paper sheets 23, only the lowest layer of the paper sheet 23 is pulled out by the feed roller 15.
The paper sheets 23 in the next layer and below are returned to the stocker 10 side by the reverse roller 16. When a sheet of paper 23 is fed between the feed roller 15 and the reverse roller 16, the slipping action of the torque limiter 59 causes the reverse roller 16 to move due to the frictional force with the sheet of paper 23 being conveyed. Rotates counterclockwise. At this time, reverse roller shaft 5
8 receives rotational force in the counterclockwise direction from the reverse roller 16 via the torque limiter 59, and this rotational force is applied to the gear 54.
．． 55, transmission shaft 53, and gears 56 and 57, the one-way clutch 52 prevents rotational movement of the feed roller shaft 48 in the reverse direction. The paper sheets 23 separated by the paper sheet separating means 13 in this manner are detected by the paper sheet detector 31, and then transported by the transport rollers 14. Note that the detection signal from the sheet detector 31 is used as a command signal for operating other parts or as a jam detection signal. During this paper feeding operation, the feed roller If continues until the leading edge of the paper sheet 23 passes over the paper sheet separation means 13 and reaches the conveyance roller I4.
Even if the feed roller 11 is stopped after the transfer roller I4 is driven, the sheet 23 can be reliably drawn out to a predetermined position by the conveyance roller I4.

Here, as shown in FIG. 11, the pressure due to the loading amount of paper sheets 23 on the feed roller 11 in the stocker 10 is PA, and the pressure on the reverse roller 16 on the feed roller 15 is PA.
If the pressure is P6, the return force of the paper sheet 23 by the torque limiter 59 is TA1, the friction coefficient between the feed roller 15 and the paper sheet 23 is μm, and the friction coefficient between the paper sheets 23 is μm, then
When the feed roller 11 is driven until the leading edge of the paper sheet 23 reaches the conveyance roller 14, the following relationship exists.

In addition, as in the conventional case, the tip of the paper sheet 23 is placed between the conveyance port and the roller 14.
In a state in which the feed roller 11 is stopped before reaching .

1”! p8 > T A + P A...■μ
r μr From equations ① and ②, it can be seen that P is smaller in the real case. That is, it is possible to reduce the pressure P[l of the reverse roller 16 on the feed roller I5, thereby reducing stains on the printing surface. This PIl decreases as the pressure PA of the sheet 23 on the feed roller 11 increases.
By increasing the amount of paper sheets 23 loaded on the stocker 1o, it is possible to reduce the frequency of replenishing paper sheets to the stocker 10. In addition, in this embodiment, all rollers 11, 14, 15°1
Since the outer circumferential surfaces of the sheets 6 and 6 are made of the same material, the coefficient of friction μ with respect to the paper sheet 23 is the same.

Further, when the leading edge of the sheet 23 reaches the conveyance roller 14 or just before that, the power supply to the solenoid 62 is cut off, so the sheet presser 18 retreats upward based on the above-described operation. Further, the rotational position of the feed roller 11 is detected by a detection signal from a photoelectric detector 40 that detects the rotational position of a slit disk 42 that rotates integrally with the feeder roller 11, and the leading edge of the paper sheet 23 is adjusted based on this detection signal. After passing the receiver to the transport roller 14,
By turning off the electromagnetic clutch 49, the feed roller 11 is stopped with its cutout portion 11b facing the sheet 23. Moreover, since the paper sheet 23 is supported by the flange 1lcl of the hub lla formed of a low-friction member, the resistance of the feed roller 11 to the paper sheet 23 pulled out from the stocker 10 can be reduced. This makes it possible to reliably pull out the paper sheets 23 in the stocker 10. In addition, the resistance given to the paper sheet 23 by the stopped feed roller 11 is /J'
Since the paper sheet 2 on the stocker 10 can be
The loading capacity of 3 can be increased. Furthermore, roller 3
7 and the recess 38 of the positioning cam 39, the stopping position of the feed roller 11 can be accurately determined.

Here, by turning off the electromagnetic clutch 49 and cutting off the power to the feed roller shaft 32 just before the roller 37 falls into the center of the recess 38, the force accompanying the movement of the roller 37 falling into the center of the recess 38 is used. The feed roller 11 can be rotated together with the feed roller shaft 32 to a fixed position and then stopped. As a result, the feed roller 1
1 can be accurately determined.

Furthermore, the leading edge of the paper sheet 23 set in the stocker 10 is located in front of the paper sheet separating means 13, and when the -th sheet 23 is sent out, the frictional resistance between the sheets 23 causes the second and subsequent sheets to be separated. 23 approaches the sheet separation means 13, the driving time of the feed roller 11 is extended by a driving means (not shown) during the first sheet feeding operation based on the detection signal of the photoelectric detector 40. , it is possible to solve the problem of an insufficient amount of paper sheets 23 being delivered by the delivery roller 11 during the first paper feeding operation.

Furthermore, when the feed roller II is rotated to feed the next sheet 23 from a state in which the cutout portion 11b is opposed to the paper sheet 23 and the feed roller 11 is stopped, the length of the sheet 23 to be used is Even if the edge of the missing circular portion 11b kicks the trailing edge of the paper sheet 23 due to its short length, the missing circular portion 11b
Since the low-friction member lid provided on the paper sheet 23 can be slid against the paper sheet 23, folding or damage to the rear end of the paper sheet 23 can be prevented, and the stocker 10 can be prevented from folding or damaging the rear end of the paper sheet 23. It is possible to prevent the stacked state of the upper paper sheets 23 from collapsing. In this case, by forming a curved surface on the edge portion of the low-friction member lid or by providing a roller with a small diameter, damage caused by kicking the paper sheet 23 can be more effectively prevented.

Furthermore, since an expanding concave portion 29 that expands upward is formed at the entrance of the paper feed path 12, even when a large amount of paper sheets 23 are stacked on the stocker IO, the paper feed operation by the feed roller 1] As shown in FIG. 9, the upper sheet 23 is brought into contact with the stepped portion 30 of the expansion recess 29, and the sheet 23 below the middle portion is
3 can be brought close to the paper sheet separating means side 13,
Therefore, it is possible to avoid a phenomenon in which paper sheets 23 become jammed near the entrance of paper feed path 12. Further, as the number of sheets 23 on the stocker lo decreases, the sheet presser 18 pushes down the sheets 23 from the expansion recess 29 toward the delivery roller 11 side, allowing them to advance toward the sheet separation means 13 side. be able to.

Here, as shown in FIG. 8, the height from the bottom surface of the stocker 10 to the top surface of the expansion recess 29 is 81, and the height from the bottom surface of the stocker 10 to the top surface of the paper feed path 12 on the back side of the stepped section 30 is 81. Assuming that the length is 82, the protruding height of the feed roller 11 from the bottom surface of the stocker 10 is h, and the stacking height of the paper sheets 23 is, it is desirable that S + > S Z and S + > t + h. Also, the inclination angle O of the stepped portion 30 is set to 30
By setting the distance between ° and 60', the feed roller 11
When the sheet 23 that is in contact with the stepped portion 30 of the expansion recess 29 is lowered by the sheet presser 18 prior to the rotation of the sheet 23, the sheet 23
Even if the tip of the holder is broken and caught in the stepped part 30,
As the sheet 23 is lowered, its leading edge can be separated from the stepped portion 30. Thereby, the cause of misfeeding of the paper sheets 23 can be reduced.

As shown in FIG. 10, the hub lla of the feed roller 11 and the flange lid formed by a low friction member
and may be formed from separate members.

In this case, by freely rotating the flange lld, the resistance to the paper sheet 23 pulled out by the conveyance roller 14 can be further reduced. The present invention is also applicable to paper feeding devices for other office machines such as printers and facsimile machines.

Effects of the Invention As described above, the invention of claim 1 includes a stocker in which paper sheets are placed in a stacked state, a paper feed passage whose entrance is opened toward the tip of the stocker, and opposing feed rollers. a sheet separating means having a friction member and disposed in the sheet feeding path; a conveying roller disposed downstream of the sheet separating means in the sheet feeding path; and a separation distance from the conveying roller to the sheet separating means. and a feed-out roller that is placed at a position separated from the sheet by a distance shorter than the total length of the sheet and comes into contact with the sheet on the stocker, so that the leading edge of the sheet passes through the sheet separating means and reaches the conveyance roller. The sheets in the stocker can be sent out by the delivery roller, so that even if the delivery roller is subsequently stopped,
This has the effect that the paper sheet can be reliably pulled out to a predetermined position by the conveyance roller.

As described above, the invention of claim 2 uses the half-moon-shaped delivery roller in claim 1 which has a missing circular part on a part of the outer periphery. By stopping the feed roller in this state, it is possible to reduce the resistance of the feed roller against the paper sheets being pulled out from the stocker, and thereby it is possible to promote the prevention of slips or non-feeding of the paper sheets. Since the resistance exerted on the paper sheets from the rollers can be reduced, it is possible to increase the amount of paper sheets loaded on the stocker and reduce the frequency of replenishing the stocker with paper sheets.

As described above, the invention of claim 3 includes a position detection means for detecting the rotational position of the half-moon-shaped delivery roller, and a position detection means for detecting the rotational position of the half-moon-shaped delivery roller, and a detection signal of the delivery roller at the time of the first paper feeding operation based on a detection signal of the position detection means. Since the drive means for extending the drive time of the rollers is provided, the sheets set in the stocker are positioned in front of the sheet separation means, and when the -th sheet is sent out, the frictional resistance between the sheets causes the sheets to be separated. In view of the fact that sheets of paper less than the first sheet approach the sheet separation means, the drive means determines the drive time of the feed roller during the first paper feeding operation based on the detection signal of the position detection means that detects the rotational position of the feed roller. By extending the length, it is possible to solve the problem of insufficient amount of paper sheets being sent out by the sending roller during the first paper feeding operation.

As described above, the invention of claim 4 is characterized in that in claim 2 or 3, a low-friction member is provided that protrudes from the half-moon-shaped cut-out portion of the feed roller to the upper part of the bottom surface of the stocker. When the feed roller is stopped while facing the paper sheet, the paper sheet can be supported by the low-friction member, so the resistance to the paper sheet being pulled out from the stocker by the transport roller can be effectively reduced. This has the effect of promoting prevention of slippage or non-feeding of paper sheets.

jjf The invention of claim 5 is as described above, in claim 2, 3, or 4, since a low friction member is provided in the half-circle part of the half-moon-shaped feeding roller, the paper sheet is fed with the hollow part facing the sheet. When the roller is stopped and the feed roller is rotated to feed the next sheet, the edge of the cut-out part of the feed roller will cause the paper to fall behind due to the short length of the sheet being used. Even if the edge of the paper is kicked, the low-friction member provided in the missing circle can be slid against the paper sheet, and as a result,
This has the effect of preventing folding or damage to the trailing edge of the paper sheet, as well as preventing the state of stacking the paper sheets on the stocker from collapsing due to folding or damage to the trailing edge of the paper sheet.

As mentioned above, the invention of claim 6 is based on claims 1 and 2゜3.4.
or 5, a sheet presser is provided on the top of the feed roller that contacts the lowest layer of sheets stacked on the stocker so as to be movable up and down, and a sheet presser is provided on the upper guide surface of the sheet feeding path on the upstream side of the sheet separating means. Since the expanding concave portion is formed to expand toward the entrance of the paper feed path, the paper sheets in the stocker can be fed out by the feeding roller until the leading edge of the paper sheet passes the paper sheet separation means and reaches the conveyance roller. As a result, even if the feed roller is subsequently stopped, the paper sheet can be reliably pulled out to the specified position by the transport roller. Because the recess is formed, even when a large amount of sheets are stacked in the stocker, the upper layer of sheets will come into contact with the step of the expanding recess, and only the sheets below the middle part will be placed on the sheet separation means side. Therefore, as the number of sheets on the stocker decreases, it is possible to spread out the sheets using the sheet presser. It has the effect that it can be pushed down from the recessed portion toward the feed roller side and allowed to advance toward the sheet separation means side.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a longitudinal side view, FIG. 2 is a longitudinal front view showing the support structure of the feed roller, and FIG. 3 is a section taken along line A-A in FIG. 2. 4 is a side view showing the power transmission structure to the feed roller, FIG. 5 is a side view showing the drive structure of the sheet presser, and FIG. 6 is a horizontal view showing the drive structure of the feed roller and reverse roller. A sectional view, FIG. 7 is a side view showing the internal structure of the copying machine,
FIGS. 8 and 9 are longitudinal side views showing the entrance of the paper feed path;
FIG. 10 is a horizontal sectional view showing a modified example of the delivery roller;
FIG. 11 is a side view showing the paper feeding operation. 10...Stocker, 11...Feeding roller, 11
b... missing circular part, lid, lie... low friction member, 1
2... Paper feed path, 13... Paper sheet separation means, 14...
・Conveyance roller, 15... Feed roller, 16...
Reverse roller, 18... Paper leaf presser, 23... Paper leaf, 29... Expansion recess, 43... Position detection means, i71 Agent Akira Aiki□;. ] A j 15 wa J, I, I shi

Claims (1)

[Scope of Claims] 1. A stocker on which paper sheets are placed in a stacked state, and a feed roller and a friction member facing each other on a paper feed path whose inlet is opened toward the tip of the stocker. a sheet separating means disposed in the sheet feeding path; a conveying roller disposed downstream of the sheet separating means in the sheet feeding path; and a separation distance from the conveying roller that is shorter than the total length of the sheet. A paper feeder comprising: a feed roller disposed at a position where the paper sheets are separated from each other so as to come into contact with the paper sheets on the stocker. 2. The paper feeding device according to claim 1, characterized in that a half-moon-shaped feed roller is used which has a cutout portion on a part of its outer periphery. 3. A position detection means for detecting the rotational position of the half-moon-shaped feed roller, and a drive means for extending the drive time of the feed roller during the first paper feeding operation based on a detection signal from the position detection means. The paper feeding device according to claim 2, characterized in that: 4. The paper feeding device according to claim 2 or 3, further comprising a low-friction member projecting from the half-moon-shaped cutout portion of the feed roller to the upper part of the bottom surface of the stocker. 5. The paper feeding device according to claim 2, 3 or 4, characterized in that a low friction member is provided in the missing circular portion of the half-moon-shaped feed roller. 6. A sheet presser is provided on the upper part of the feed roller that contacts the lowest layer of sheets stacked in the stocker so as to be able to move up and down, and is located on the upper guide surface of the sheet feed path upstream of the sheet separating means. 6. The paper feeding device according to claim 1, further comprising an expanding concave portion that expands toward the entrance of the paper feeding path.