JPH10167502A - Paper feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate restitution of a jamming mechanism and eliminate risk of thrust-in double feed of sheets in an automatic sheet feeding device whereby sheets of paper stacked on a sheet table are separated and one by one transported by a separative transport means consisting of a separating member and a feeding member contacted with sheet with a specified pressure. SOLUTION: Even on the way of feeding a sheet S, if a sheet table 8 is pressed in the direction of disengaging the sheet contact with a feeding member 14, it 14 separates from a separating member 15 in association with the pressing action. A transport aid member 16 confronting the feeding member 14 to press it is furnished in a position downstream of the member 14 about the sheet transport direction, and a double feed hindering member 17 is provided capable of moving as intruding to the sheet transport path or avoiding it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a sheet feeder provided in an image forming apparatus such as a copier, a laser beam printer, an ink jet printer, a facsimile, and other sheet using apparatuses.

More specifically, a sheet material stacked in a stacked manner on a sheet material mounting table is separated and fed one by one by a separating and feeding means including a feeding member and a separating member which abut against the sheet material at a predetermined pressure. The present invention relates to an automatic paper feeder.

[0003] Sheet materials include, for example, transfer materials, recording paper, printing paper, OHP paper, manuscripts, envelopes, postcards, cards, films and the like. The material is not limited to paper, plastic, metal,
It may be a cloth or the like.

[0004]

2. Description of the Related Art For example, Japanese Patent Publication No. 3-6101 proposes a paper feeder using a friction separation system, which is provided with a sheet stop member which is effective in preventing double feed of sheets. . In summary, the sheet feeding device, when the sheet stop member, when the separation belt portion and the separation portion are pressed against each other,
The sheet is retracted to a position where it does not hinder the separation and conveyance of the sheet.When the separation unit and the paper feed unit are separated, the sheet is moved to a position where the conveyance of sheets other than the sheet being separated and conveyed is prevented, and This is a sheet feeding device in which an opposing roller that conveys a sheet presses a feeding member.

[0005]

However, in this apparatus, when the separation section is separated from the conveyance separation belt section, the conveyance separation belt section is moved from the position where the sheet stop member interrupts the sheet conveyance path. The sheet stop member moves to the position where the sheet conveying path is released at the same time when the separation section is pressed against the sheet separation section, so that the sheet bundle may reach the separation section at a stretch. Feed), the sheet tip was broken, and in severe cases, there were quality defects such as breakage of the sheet tip, and the separation performance was unstable.

Further, since the separation portion is separated from the transport separation belt portion, the sheet can be extended only until the sheet stop member comes into contact with the transport separation belt portion. In addition, since friction separation is used, static electricity is generated due to friction between sheets peculiar to friction separation, particularly in a low-humidity environment (eg, winter in Japan). At the same time as separating the separation unit, the following two or three sheets are stuck to the sheet being separated and conveyed. Therefore, in order to secure the conveyance path of the sheet being separated and conveyed and to prevent the conveyance of the following sheets, a gap for only one sheet must be provided between the sheet stop member and the conveyance separation belt part. Did not. Therefore, since the thickness varies depending on the type of sheet, it is difficult to secure a gap for only one sheet.

Therefore, if the gap is adjusted to a recording sheet having a small thickness, the transport load of the sheet having a thickness greater than the gap becomes a load for transporting the sheet. The sheet stopped between the conveyor and the separation belt, resulting in a sheet conveyance failure.

Further, if the gap is adjusted to a thick sheet, it is not possible to prevent double-feeding of the sheet due to the sticking of the sheets due to the static electricity in the conveyance of the sheet having a thickness smaller than the gap. I have.

In addition, since the separation section is separated from the transport separation belt section, the sheet stop member can be extended only until the sheet stop member comes into contact with the transport separation belt section. However, the sheet stop member overlaps the transport separation belt section. If the sheet stop member is pushed up to this point, the sheet is conveyed while being distorted like a wave in a direction orthogonal to the sheet conveying direction. This is because the sheet conveyance path formed by the conveyance separation belt portion and the sheet stop member has a comb shape in the thickness direction of the recording sheet. As a result, the load becomes a conveyance load of the sheet, and the sheet becomes wavy, and the sheet is significantly bent.

Further, when the sheet is jammed (JAM), if the jam sheet is sandwiched between the feeding member and the conveying roller which is pressed against the sheet, the jam sheet can be easily pulled out. Therefore, if the jam sheet is forcibly pulled out, the sheet is torn, and it is very difficult to take out the torn sheet from the inside of the apparatus. Blocked the transport path and caused jams one after another.

The present invention solves the above-mentioned problems, that is, a) improved operability of a user to replenish and replenish sheets and set a sheet; b) rush double feed and non-feed of sheets; C) Sheet jams can be easily removed, d) User-friendliness is improved, cost is reduced, and quality is improved. It is another object of the present invention to provide a paper feeding device.

[0012]

According to the present invention, there is provided a sheet feeding apparatus having the following configuration.

(1) The sheet materials stacked in a stack on the sheet material mounting table are separated and fed one by one by a separating and feeding means comprising a feeding member and a separating member which are brought into contact with the sheet material at a predetermined pressure. Means for releasing the contact pressure between the feeding member and the separating member of the separating / feeding means in the automatic sheet feeding device; and the sheet material mounting table holds the loaded sheet material at a predetermined pressure with the separating / feeding means. Means for releasing the contact of the loaded sheet material by the sheet material mounting table with the feed member, even during the sheet feeding operation. A sheet feeding device configured such that when the sheet material stacking table is pressed in a direction in which the abutting of the placed sheet material with respect to the feeding member is released, the feeding member and the separation member are separated in association with the pressing.

(2) The sheet feeding apparatus according to (1), wherein the sheet loading table is supported by the pressing operation so as to be rotatable in a direction away from the sheet feeding member from a sheet loading position.

(3) A transport assisting member is provided on the downstream side of the feeding member in the sheet material transport direction so as to face the feeding member and press the feeding member. Paper feeder.

(4) The sheet feeding device according to (3), wherein the transport assisting member is configured to be separated from the feeding member by the pressing operation of the sheet material loading table.

(5) The feeding member is a feeding roller,
The sheet feeding device according to any one of (1) to (4), wherein the separation member is a separation roller, and the conveyance auxiliary member is an auxiliary roller.

(6) The feeding roller as the feeding member is formed in a half-moon shape, thereby releasing the contact of the feeding roller with the separating roller as the separating member. The paper feeding device according to (1).

(7) The sheet feeding device according to any one of (1) to (6), further comprising a sheet material double feed prevention member that can move into and out of the sheet material conveying path so as to be able to avoid it.

(8) The position where the sheet material accompanying double-feed preventing member protrudes into the sheet material conveying path is substantially the same as the leading end abutting portion of the sheet material stacked on the sheet material mounting table. The paper feeder according to (7), which is on the same side.

(9) The position of the double-feed preventing member retracted from the sheet transporting path is located downstream of the separating and feeding means in the sheet feeding direction and in the sheet transporting guide. It is a position that does not protrude from the surface (7)
A paper feeder according to claim 1.

(10) A period from when the loaded sheet material on the sheet loading table abuts on the feeding member to when the feeding member of the separating / feeding means abuts on the separating member. ,
The sheet feeding device according to (7), wherein the sheet material double feed prevention member is located at a position protruding into the sheet material conveyance path.

(11) The sheet material mounting table may be configured such that an end of the sheet material stacked on the sheet material mounting table is
The paper feeding device according to any one of (1) to (10), wherein the paper feeding device is provided at an angle to an installation surface so as to be placed close to the separation feeding unit by its own weight.

<Operation> a) Even during the sheet feeding operation, when the sheet material loading table is pressed in the direction of releasing the contact of the sheet material with the feeding member, the sheet feeding is performed in conjunction with the pressing. By configuring the member and the separating member to be separated, during jam processing, the sheet material stacking table is pressed to separate the feeding member and the separating member so that the jammed sheet material sandwiched therebetween is not subjected to any load. It can be easily pulled out of the apparatus and removed. That is, it is possible to easily perform the jam processing of the sheet material, and it is possible to prevent the occurrence of the trouble of the sheet material failure due to the damage of the sheet material and the damage of the sheet material.

B) The sheet material loading table is moved by a pressing operation.
By being rotatably supported in a direction away from the sheet feeding member from the sheet material stacking position, the separating member is pressed against the sheet feeding member in a normal state other than the time of a jam clearance to reliably perform the sheet material separating operation. Can be done.

C) By providing a conveyance auxiliary member which is opposed to the feeding member and presses the feeding member downstream of the feeding member in the sheet conveying direction, the conveyance of the separated sheet material is provided. More stable and reliable.

D) The auxiliary conveyance member is configured to be separated from the feeding member by the pressing operation of the sheet material loading table. At this time, the sheet loading table is pressed to separate the feeding member and the transport assisting member, and the jammed sheet sandwiched therebetween can be easily pulled out of the apparatus without any load and removed.

E) The feeding roller as a feeding member is formed into a half-moon shape, and the contact of the feeding roller with the separating roller as a separating member is released, thereby simplifying the structure of the apparatus and reducing the cost. Can be reduced.

F) The provision of the sheet material double feed preventive member which can move into and out of the sheet material conveying path so as to be able to move freely can prevent occurrence of double sheet feed of the sheet material in the separated separation section.

G) The position of the double feed blocking member that protrudes into the sheet conveyance path is substantially flush with the front end abutting portion of the sheets stacked on the sheet stacking table. Thus, when the sheet material is replenished and set on the sheet material stacking table, the sheet material can be prevented from spilling into the separation unit, and a conveyance failure such as rush double feeding of the sheet material can be prevented.

H) The position of the double-feed preventive member retracted from the sheet conveying path is located downstream of the separation feeding means in the sheet feeding direction and does not protrude from the sheet conveying guide surface. By being at the position, it is possible to prevent non-feeding such as the leading edge of the sheet material being caught by the double feed preventing member with the sheet material being conveyed during separation and conveyance, and conveyance failure such as occurrence of a jam.

I) The sheet material is held between the time when the loaded sheet material on the sheet material mounting table abuts on the feeding member and the time when the feeding member of the separation feeding means and the separation member come into contact with each other. Since the double feed prevention member is located at a position protruding into the sheet material conveyance path, the front end of the sheet material is more reliably prevented from being conveyed to the separation unit having no conveyance force, and the front end of the sheet material may be broken or damaged. Quality defects and transport defects can be eliminated.

J) The sheet material mounting table is at an angle with respect to the installation surface such that the leading end of the sheet materials stacked on the sheet material mounting table is mounted by its own weight to the vicinity of the separating and feeding means. With this arrangement, the apparatus can be configured without providing a trailing end regulating guide that pushes the leading end of the sheet material to the sheet feeding unit, thereby simplifying the configuration of the apparatus and reducing the cost.

[0034]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a schematic perspective view of a facsimile apparatus as an example of an image forming apparatus provided with a sheet feeding device according to the present invention. FIG. 2 is a schematic longitudinal cross-sectional view showing the internal mechanism of the apparatus, and FIG. 3 is a block diagram of a control system of the apparatus.

(1) Overall Schematic Configuration of Facsimile Machine of the Present Example In FIG. 1, reference numeral 1 denotes an outer case (main body cover), 2 denotes a front cover of the outer case, and 3 and 4 denote front covers 2 A horizontally elongated slit-shaped document discharge port and a recording sheet discharge port provided on the upper and lower sides of the surface. The front cover 2 is shown in FIG.
As shown by the dashed line, the front door of the apparatus is opened and closed by tilting the hinge part (not shown) on the lower side toward the front and opening the front side of the apparatus.

Reference numeral 5 denotes an operation panel unit (operation unit) provided at the upper part of the apparatus, for performing operations such as transmission operation, copy operation, and scanner operation. Keys, push buttons, indicators, and the like corresponding to various operations are provided. The operation panel section 5 is raised and opened about a hinge section (not shown) on the front side as shown by a two-dot chain line in FIG. 2 so that a document conveying path of a reading system A described later can be largely opened.

Reference numeral 6 denotes a telephone handset (transmitter / receiver) disposed on one side of the apparatus, and reference numerals 7 and 8 denote a document tray and a recording paper tray disposed vertically on the rear side of the apparatus. 8a
Is a recording paper auxiliary tray that can be pulled out and stored.

In FIG. 2, A is a general code of a reading system for photoelectrically reading image information of a document, B is a general code of a paper feeding system (sheet feeding device) that separates and feeds recording paper, and C is a recording paper. This is a general code of a recording system for recording image information in the.

A) Reading System A In the apparatus of this embodiment, the reading system A is disposed above the operation panel 5 in the upper part of the apparatus, and the original tray 7, which is disposed in a downwardly inclined position, Upper and lower original transport guides 9a and 9
b, separation roller 10, friction piece 11, photoelectric reading unit 1
2 (in this example, a contact sensor (CS) is used), a feed roller 13 and the like.

One or a plurality of originals O are stacked on the original tray 7 with the image side facing downward, and the leading end of the original is inserted into the apparatus, and the separation roller 10 and the separation roller 10 are separated. The friction piece 11 pressed and urged upward is positioned at the wedge-shaped nip entrance and set.

Based on the document reading start signal, the separation roller 10 is driven to rotate at a predetermined peripheral speed in the document feeding direction by a drive system (not shown).
1, only the lowermost document of the set document O is separated by one, passes through the nip portion between the separation roller 10 and the friction piece 11, is guided by the guides 9a and 9b, and is Nip portion (reading portion) of the feeding roller 13 and 12
Is sent to The friction piece 11 acts to separate a plurality of documents one by one.

The photoelectric reading unit 12 is pushed up and urged by an urging spring 12 a to bring the photoelectric reading surface into contact with the lower surface of the feeding roller 13. The feed roller 13 is configured as a white roller, and also serves as a white background for reading.

The feed roller 13 is driven to rotate at a predetermined peripheral speed in the document feeding direction by a drive system (not shown) based on a document reading start signal. The document separated and fed one by one by the separation roller 10 and the friction piece 11 enters the nip portion between the photoelectric reading unit 12 and the feeding roller 13, and the feeding roller 13 causes the image to be read on the photoelectric reading surface of the photoelectric reading unit 12. The lower side, which is the side, is conveyed while sliding closely. In this process, the image information of the document is sequentially photoelectrically read by the photoelectric reading unit 12. The photoelectric reading unit 12 irradiates the original with light, and converts the reflected light of the irradiated surface of the original into an electric signal (a time-series electric digital image signal).

The image signal of the document photoelectrically read by the photoelectric reading unit 12 is transmitted to another machine (the other party's facsimile machine) or transmitted to its own recording system C for copying, depending on the operation mode. You.

The original on which the image information has been read is placed on the front cover 2.
The document is discharged from the document discharge port 3 at the top of the surface to the front side of the apparatus, and is received by a document discharge tray (not shown).

A plurality of set originals O on the original tray 7 are separated and fed one by one sequentially from the lower one as described above, photoelectrically read, and discharged from the original discharge opening 3 to the original discharge tray. Be loaded.

When an original jam occurs in the original conveying path of the reading system A, the original conveying path of the reading system A is greatly opened by raising and opening the operation panel unit 5 as shown by a two-dot chain line in FIG. The jam document can be easily taken out.

B) Paper feed system B The paper feed system B is a paper feed device configured according to the present invention.
Since this will be described in detail in section (2) below, it will be briefly described here.

In the apparatus of the present embodiment, the paper feeding system B is disposed at the rear of the apparatus, and the recording paper tray 8, which is disposed in a downwardly inclined position as a sheet material (recording paper, recording sheet) loading table, A paper feed roller 14 (a half-moon shaped roller in this example) as a recording paper feeding member, a friction separating roller 15 as a recording paper separating member, an auxiliary roller 16 as a recording paper transporting auxiliary member,
It comprises a recording paper return lever 17 and the like as a recording paper double feed prevention member.

The recording paper tray 8 is an up-and-down swing type sheet loading table (pressing plate), and a rear side hinge portion is provided above a fixed base plate 18 disposed on the back side of the apparatus in a downwardly inclined position. 8b
Are arranged so as to freely swing up and down around the center, and are constantly pushed up and biased about the hinge portion 8b by a biasing spring 19 interposed between the recording paper tray 8 and the fixed base plate 18.

The recording paper auxiliary tray 8a is stored between the recording paper tray 8 and the base plate 18, and the recording paper tray 8 can be extended and extended by being pulled out.

In this embodiment, the recording paper S is made of plain paper cut to B4 or A4 size.
And a recording paper auxiliary tray 8a pulled out as necessary, and a number of sheets equal to or less than a predetermined maximum number limited by a recording paper height restriction plate 21 provided on the apparatus rear cover 20 is stacked. Is stored. A recording paper side guide (not shown) regulates the width of the recording paper S stacked and stored in the trays 8a.

The leading end side of the fixed base plate 18 is bent at a substantially right angle above the base plate 18 to form a recording paper leading end abutting plate portion 22, and the recording paper S loaded and stored in the trays 8.8a is inclined forward and downward. A force that always slides down on the tray 8.8a by its own weight acts on the tray 8.8a, and its front end side abuts against the inner surface of the abutment plate portion 22 and is received.

The paper feed system B is operated based on the paper feed start signal, and the uppermost sheet of the stacked recording paper S is separated and fed one by one, and guided by the recording paper transport guide 23 to be fed to the recording system. Enter C.

C) Recording System C In the apparatus of this embodiment, the recording system C is disposed in front of the paper feeding system B and below the reading system A in the apparatus.

The recording system C includes an image signal transmitted from another device,
In the copy mode, an image is recorded on the recording paper supplied from the paper supply system B in accordance with the image signal of the original photoelectrically read by the reading system A and transmitted. Various principles and methods can be adopted as image recording means for recording images on recording paper. In this embodiment, an apparatus generally called an ink jet recording apparatus is employed.

The recording system C includes a paper transport roller 24, a recording paper presser 25, a pinch roller 26, a platen plate 27, a recording cartridge (recording head, print head) 28, a discharge roller 29, a spur roller 30, and the like.

The FL roller 24 and the paper discharge roller 29 are controlled to rotate in a predetermined direction in the recording paper feed direction. Pinch roller 2
The spur roller 6 and the spur roller 30 abut on the upper surfaces of the FL roller 24 and the discharge roller 29, respectively, and are driven to rotate. Recording paper presser 2
A pinch roller 26 is pressed against the FL roller 24 while also serving as an upper guide of the recording paper conveyed from the paper feeding system B.

The recording cartridge 28 is provided with a guide rail member 31 in the lateral direction of the apparatus (in FIG. 2, in the direction perpendicular to the drawing).
The slider 31 that is controlled to move along a 31b is held in a posture in which the printing function surface side faces downward, and is controlled to move in the lateral direction of the apparatus together with the slider 31. The platen plate 27 is a recording paper backup member that faces the downward print function surface of the recording cartridge 28.

The recording paper conveyed from the paper feeding system B is nipped between the FL roller 24 and the pinch roller 26 and conveyed between the recording cartridge 28 and the platen plate 27.
Image recording is received by the recording cartridge 28. In this example, the recording cartridge 28 is configured to perform serial printing while moving in the width direction of the recording paper (the direction orthogonal to the transport direction of the recording paper).

Then, the recording paper after the printing and recording is performed by the paper discharge roller 2.
The paper is conveyed by the spur roller 30 facing the printing paper 9 so as not to stain the printing surface, and is discharged from the recording paper discharge port 4 at the lower portion of the front cover 2 to the front side of the apparatus.

The recording cartridge 28 includes the front cover 2
2 is opened as shown by a two-dot chain line in FIG.

In FIG. 2, reference numeral 32 denotes a main control board (main control unit) for controlling the facsimile machine, 33 denotes a power supply unit for supplying power to the entire facsimile machine, and 34 denotes an operation provided inside the operation panel section 5. This is a board control board.

D) Control System FIG. 3 is a block diagram showing the device control system. 35 is a modem board unit, and 36 is a communication board unit for connecting a telephone.

The main control unit 32 is used as a CPU 32a for controlling the entire apparatus, a ROM 32b for storing various programs and various data, and a work area of the CPU 32a, and for temporarily storing various data such as the number of recordings. RAM 32 for storing and registering various data
c, an input / output switching interface 32d, a line memory 32e, an encoding / decoding unit 32f, a memory buffer (buffer memory) 32g, and the like.

The line memory 32e is a memory for storing the image of each line of the image data. In the case of transmitting or copying a document, the line memory 32e stores one line of image data from the document reading system A and receives the image data. In the case of (1), data for one combined line is stored. The image data stored in the line memory 32e is C
The recording system control code is added through the PU 32a, and the CPU of the recording system C is transmitted from the input / output switching interface 32d.
The image is output to C1 and the image is recorded by the CPU C1 decoding the recording system control code.

The encoding / demultiplexing unit 32f encodes the image information to be transmitted by MH encoding or the like, or decodes the received encoded image data to convert it into image data. The memory buffer 32g stores the transmitted and received encoded image data.

(2) Details of the paper feeding system B (paper feeding device) a) Structure FIG. 4A is a perspective model view of the paper feeding roller 14 of the paper feeding system B, and FIG. FIG. 5 is a perspective model view of the friction separating roller 15 and the auxiliary roller 16 disposed below the paper roller 14.
FIG. 6A is a plan view of the same part, and FIGS. 6A and 6B are explanatory views of a mechanism for pushing down the friction separating roller and the auxiliary roller unit.

As described above, the fixed base plate 18 on which the recording paper tray 8 serving as a vertically oscillating type sheet material mounting table is disposed on the upper side is bent upward at a substantially right angle to form a recording paper front end abutting plate. The recording paper transport guide 23 extending to the recording system C by extending the distal end side of the recording paper distal end abutting plate portion 22 is provided in a series in the apparatus of this embodiment.

Paper feed roller 14 as recording paper feeding member
Is a half-moon-shaped roller in the present example, and is disposed above the meeting portion of the recording paper leading end abutting plate 22 and the recording paper transport guide 23. Reference numeral 14a denotes a paper feed shaft on which the paper feed roller 14 is fixedly supported. Although not shown in the drawing, the paper feed shaft 14a is rotatably supported between side plates of the apparatus, and is provided in the paper feed direction for each paper feed via a one-rotation clutch mechanism.
It is intermittently driven for rotation. The paper feed roller 14 is
Rotate with a.

A friction separating roller 15 as a recording paper separating member is provided on a portion of the recording paper transport guide surface directly below the paper feed roller 14 at a position upstream of the center of the surface in the recording paper transport direction. The through hole 23a to be exposed and the through hole 23
The two through-holes 23b, 23b, which allow the auxiliary rollers 16, 16 as the recording paper transporting auxiliary members to face the positions on the left and right sides of a, respectively, which are displaced downstream of the through-hole 23a in the recording paper transport direction. Formed and provided with these through holes 2
The recording paper transport guides 23a, 23b and 23b are respectively provided.
The friction separation roller 15 and the auxiliary rollers 16 are arranged from the lower side.

In the apparatus of this embodiment, as shown in FIG. 6, the above-mentioned friction separating roller 15 and auxiliary rollers 16 are provided as a single unit 37 (friction separating roller / auxiliary roller unit) in a common housing. The unit 37 is held by bearings in an arrangement relationship and incorporated, and the unit 37 is guided vertically freely by a guide member (not shown) below the recording paper conveyance guide 23, and is constantly pushed up and biased by a biasing spring 38. In the free state, the unit 37 is connected to the recording paper transport guide 23 as shown in FIG.
In a state where it is received on the lower surface of the. 39 is a fixed spring receiving member. Reference numerals 15a and 16a denote rotation center axes of the friction separation roller 15 and the auxiliary roller 16, respectively.

In this state, the friction separating roller 15 and the auxiliary rollers 16
a, 23b, 23b, projecting above the upper surface of the recording paper transport guide 23 by a predetermined amount.

In the present embodiment, the friction separating roller 15 is a so-called retard roller that is driven to rotate in the recording paper return direction via a torque limiter (not shown). Auxiliary roller 16
Reference numeral 16 denotes a free rotation roller.

When the half-moon-shaped paper feed roller 14 rotates, the frictional separation roller 15 and the auxiliary roller projecting from the through holes 23a, 23b, 23b to the upper surface side of the recording paper conveyance guide 23 by a predetermined amount as described above. The outer surface of the arc-shaped portion of the feed roller 14 contacts the upper surface of the rollers 16. At this time, the frictional separation roller 1
5 and the auxiliary rollers 16 are pushed, so that the unit 37 slightly sinks against the urging spring 38, and the reaction force causes the arc-shaped portion of the feed roller 14 and the friction separating roller 1 to move.
5, the arc-shaped portion of the feed roller 14 and the auxiliary roller 16
16 contact with a predetermined pressing force.

Numeral 40 denotes a pressing member of the unit 37. As will be described later, a paper jam occurs in the paper feeding process, and the recording paper is sandwiched between the paper feeding roller 14, the friction separating roller 15, and the auxiliary roller 16. When the apparatus is stopped in the state, the unit 37 is pushed down to
This is to release the jammed recording paper from being sandwiched between the friction recording roller 15 and the auxiliary roller 16 to facilitate the removal of the jammed paper.

The member 40 is located above a receiving plate 37a provided integrally with the unit 37.
6A, but does not interfere with the receiving plate 37a by lowering and presses the receiving plate 37a to lower the unit 37 against the spring 38 as shown in FIG. 6B. I do.

In the present embodiment, the pressing member 40
Is operated in conjunction with the swinging operation of the recording paper tray 8, which is a vertically oscillating type sheet material loading table, in the overstroke range α.

That is, the recording paper tray 8 is always pushed up and biased around the hinge portion 8b by the biasing spring 19 interposed between the recording paper tray 8 and the fixed base plate 18 as described above. The recording paper tray 8 is pushed down to a predetermined standby position against a biasing spring 19 by a tray presser such as a cam-shaped member (not shown) interlocked with the rotation of the paper feed shaft 14a during the paper feeding standby state, and at that position. It has been stopped. FIG. 6A shows the recording paper tray rising stop standby state.

The recording paper tray 8 which has been stopped and is in the standby state is pressed by the finger F against the urging spring 19 against the upper surface of the tray 8 or the stacked recording paper S on the tray 8 as shown in FIG. (B) As shown in FIG. 3B, there is room for downward rotation until the downwardly projecting edge 8c of the tip end of the tray 8 abuts against the inner surface of the fixed base plate 18 and is received. When the pressing F is released, it is pushed up by the urging spring 19 to rotate upward, and returns to the state of the sheet supply standby in which it is stopped at the predetermined standby position in FIG. The vertical swing margin α of the recording paper tray 8 in FIGS. 6A to 6B and, conversely, in FIGS. 6B to 6A is the overstroke range of the recording paper tray 8.

In the apparatus of this embodiment, the unit 37 is moved downward against the spring 38 by lowering the member 40 in conjunction with the lowering movement of the recording paper tray 8 in the overstroke range α (FIG. 6 (a)). ) View → (b) view), the member 40 is lifted in conjunction with
The unit 37 is returned to the normal state by releasing the pressing force on the unit 7 (FIG. 7B → FIG. 7A).

The pressing member 40 may be a member provided integrally with the recording paper tray 8, or connected to the tray 8 via a lever, a link, or the like, and linked with the vertical swing of the tray 8 in the over stroke range α. It is also possible to use a member that operates.

A pair of recording paper return levers 17 as recording paper double feed prevention members are provided on the left and right sides of the paper feed roller 14. A member of the same shape fixed at the same phase angle to the lever shaft 17b rotatably supported between the device side plates in front of the abutting plate portion 22,
Rotates forward and backward integrally with the forward and backward rotation of. The claw-shaped portions (hook portions) 17a are provided at the leading end portions of the recording paper return levers 17 and 23c. The leading ends of the recording paper corresponding to the positions of the pair of left and right recording paper return levers 17 are provided. A recording paper return lever access hole formed and provided so as to straddle the abutting plate portion 22 and the recording paper transport guide 23 portion.

The pair of left and right recording paper return levers 17.
When the lever shaft 17b is turned forward, the lever 17 is positioned in the lever access hole of the recording paper front end abutting plate 22 as shown in FIG. The "first posture state" in which the claw-shaped portion 17a on the leading end projects above the upper surface of the recording paper transport guide 23 from the upper edge of the recording paper leading end abutting plate 22, and the reverse rotation of the lever shaft 17b. As a result, as shown in FIG. 8, the claw-shaped portion 17 a on the tip side falls down from the upper surface side of the recording paper transport guide 23 to the “second posture state” where it is retracted below the recording paper transport guide 23. Switching is controlled.

The lever shaft 17b is constantly biased by a biasing spring (not shown) in the forward rotation direction to bring the recording paper return levers 17 into the first posture state. Then, the lever shaft 17b is rotated by a predetermined angle in the reverse rotation direction against the urging spring by an action member such as a cam-shaped member (not shown) which is interlocked with the rotation of the paper feed shaft 14a. The return levers 17 are configured to be switched to the second posture state.

B) Operation of Separating and Feeding One Sheet of Recording Paper FIGS. 7 to 12 are process diagrams of the operation of separating and feeding one sheet of recording paper in the intermittent driving process of the paper feed roller 14 for one rotation.

[FIG. 7]: This is a state diagram at the time of paper feed standby. In this paper feed standby state, the half-moon-shaped paper feed roller 14 is in a standby state in which it stops rotating in a rotation angle phase posture in which a notch portion (a missing circle portion) thereof is substantially downward, and The paper feed roller 14 is separated from the friction separation roller 15 and the auxiliary rollers 16, 16 below the paper feed roller 14.

The recording paper tray 8 is pushed down to a predetermined standby position against a biasing spring 19 by a tray holder such as a cam-shaped member (not shown) interlocked with the rotation of the paper feed shaft 14a, and stops at that position. The paper feed roller 14 is separated from the upper surface of the stacked recording paper S on the recording paper tray 8.

The pair of left and right recording paper return levers 17 are switched to and held in the first posture state.
Reference numeral 17 denotes a recording paper front end abutting plate 22 which is located in the lever access hole and is substantially flush with the recording paper front end abutting plate 22, and the claw-shaped portion 17a on the front end side has a recording paper front end abutting plate. It protrudes above the upper surface of the recording paper transport guide 23 from the upper edge of the portion 22.

As described above, since the leading ends of the recording paper return levers 17 project from the upper edge of the recording paper leading end abutting plate 22 above the upper surface of the recording paper transport guide 23, the recording is performed. When the recording paper S is set on the paper tray 8 or replenished, the leading end of the recording paper is prevented from entering between the paper feed roller 14 and the frictional separation roller 15 in the separated state.

In the present embodiment, the friction separating roller 15 is a so-called retard roller which is driven to rotate in the recording paper return direction as shown by an arrow via a torque limiter (not shown) as described above. The auxiliary rollers 16 are freely rotating rollers.

[FIG. 8]: This is a state diagram at the beginning of the start of sheet feeding. In the standby state of FIG. 7 described above, when a feed start signal is input to the control circuit, a one-rotation clutch mechanism (not shown) of the feed shaft 14a is turned on, and the feed shaft 14a
It is driven to rotate. That is, the half-moon-shaped paper feed roller 14 is driven one rotation in the paper feed direction, ie, clockwise in the figure.

In the initial stage of one rotation of the half-moon shaped feed roller 14, the outer surface of the arc-shaped portion of the feed roller 14 starts to make a predetermined pressure contact with the friction separating roller 15.

When the paper feed roller 14 is securely in contact with the friction separating roller 15 at the time of the paper feed roller rotation angular phase, the action of the cam-shaped member (not shown) in which the lever shaft 17b is interlocked with the rotation of the paper feed shaft 14a. The recording paper return lever 1 is rotated by a predetermined angle in a reverse rotation direction against a biasing spring by a member.
7 and 17 are switched to the second posture state and fall down to the lower side of the recording paper transport guide 23, and the claw-shaped portion 17a on the leading end side is retracted from the upper surface side of the recording paper transport guide 23 to the lower surface side.

At the same time, the stopping of the rising of the recording paper tray 8 by the tray press such as a cam-shaped member (not shown) interlocked with the rotation of the paper feed shaft 14a is released, and the recording paper tray 8 is pushed by the urging spring 19. As a result, the upper surface of the stacked recording paper S on the tray is brought into contact with the downward outer surface of the arc-shaped portion of the paper feed roller 14 by a predetermined pressure.

The contact between the rotary paper feed roller 14 and the stacked recording paper S causes the feeding force to act on the uppermost recording paper S1 of the stacked paper S by the contact frictional force of the rotary paper feed roller 14, thereby causing the uppermost recording paper S1 to move. Feeding of the recording paper S1 is started.

As described above, after the arc-shaped portion of the paper feed roller 14 is securely brought into contact with the friction separating roller 15, the recording paper return levers 17, 17 are switched to the second posture state, and the recording paper conveyance guide 23 By retracting from the upper surface side to the lower surface side, conveyance failure such as double feeding of recording paper is prevented.

[FIGS. 9 and 10]: This is a diagram showing the paper feed progress state. As shown in FIG. 8, the uppermost recording paper S1 whose paper feeding has been started is the arc-shaped portion of the paper feeding roller 14 and the frictional separation roller 1
5 and is fed between the nip portion and the paper feed roller 14, and further rotation of the paper feed roller 14 causes the outer surface of the arc-shaped portion of the paper feed roller 14 to become an auxiliary roller as shown in FIG. 1
By forming a nip portion in contact with 6.16, the uppermost recording sheet S1 is fed between the nip portions.

With the feeding of the uppermost recording paper S1, the recording paper S1 is dragged by the recording paper S1 and the next or subsequent recording paper enters the nip portion between the arc-shaped portion of the paper feed roller 14 and the friction separating roller 15. Even after that, the recording paper after the next rank is separated and conveyed by the friction separation roller 15 which is a retard roller. As a result, double feeding of the recording paper is prevented, and only the uppermost recording paper S1 is nipped and conveyed by the nip between the arc-shaped portion of the paper feed roller 14 and the friction separation roller 15, and furthermore, the arc-shaped portion of the paper feed roller 14 The nip portion between the roller and the auxiliary rollers 16 is conveyed by being pinched and fed to the recording system C one by one.

The recording paper return levers 17 are switched to the second posture state as described above, and
The uppermost recording paper S1 separated and fed as described above is not hindered from being conveyed from the upper surface side to the lower surface side.

The recording paper tray 8 is configured such that the leading end of the fed uppermost recording paper S1 has a feed roller 14 and a friction separation roller 15
After a while after reaching the nip portion of the sheet feeding roller 14 or the nip portion between the sheet feeding roller 14 and the auxiliary rollers 16, a tray holding member such as a cam-shaped member (not shown) interlocked with the rotation of the sheet feeding shaft 14 a. Is pushed down again to the predetermined standby position against the urging spring 19 and stopped at that position. FIG. 9 is a view showing a state in which the recording paper tray 8 is pushed down again to a predetermined standby position and stopped at that position.

As described above, when the recording paper tray 8 is pushed down again to the predetermined standby position, the rotating paper feed roller 1
Although the contact between the recording paper S and the stacked recording paper S is released, the fed uppermost recording paper S1 is separated from the nip portion between the paper feed roller 14 and the friction separation roller 15, the paper feed roller 14 and the auxiliary roller 1
The paper is held between the nip portions 6 and 16 and continuously fed stably.

The nip portion between the feed roller 14 and the friction separation roller 15 and the nip portion between the feed roller 14 and the auxiliary rollers 16 nip and transport the top recording sheet S 1 by one rotation of the feed roller 14. As the driving progresses, the arc-shaped end of the semicircular feed roller 14 reaches the friction separating roller 15 and the auxiliary rollers 16 and 16 as shown in FIG. It continues until it passes and becomes a non-contact state. Also during this time, the recording sheet separating action of the friction separating roller 15 as a retard roller prevents double feed of the next and subsequent recording sheets.

The rotation of the feed roller 14 by one rotation proceeds until the end portion of the arc-shaped portion of the feed roller 14 passes through the friction separating roller 15 and the auxiliary rollers 16 and is brought into a non-contact state. In this case, the leading end side of the uppermost recording sheet S1 separated and fed one by one has sufficiently reached at least the nip portion between the FL roller 24 and the pinch roller 26 of the recording system C, and is stably conveyed by the nip portion. ing.

[FIGS. 11 and 12]: One of the paper feed rollers 14
It is a state diagram at the time of completion | finish of rotation drive. When the paper feed shaft 14a has just made one rotation, the one-turn clutch mechanism is turned off, and the rotation of the paper feed shaft 14a stops. That is, the paper feed roller 15 returns to the same rotation angle phase posture as in the paper feed standby state, stops rotating, and the notch portion becomes substantially downward, so that the paper feed roller 14 and the lower part of the paper feed roller 14 The friction separating roller 14 and the auxiliary rollers 16 are separated from each other.

As described above, even after the paper feed roller 14 completes one rotation drive and stops, only the topmost recording paper S1 that has been separated and fed one by one has the leading end at least FL of the recording system C.
The nip portion between the roller 24 and the pinch roller 26 is sufficiently reached, and the intermediate transfer is stably carried by the nip portion.

The action of the action member such as a cam-shaped member (not shown) on the lever shaft 17b that is interlocked with the rotation of the paper feed shaft 14a is released, and the lever shaft 17b is turned in the forward turning direction by the urging spring. The recording paper return lever 17
Is switched from the second posture state to the first posture state. FIG. 11 shows a state in which the recording paper return levers 17 are in the middle of a rotational transition from the second posture state to the first posture state.

During the transition from the second posture state to the first posture state, the leading ends of the recording paper return levers 17 project from the through holes 23c toward the upper surface side of the recording paper transport guide 23 and rotate. I do.

The tip 17a of the recording paper return lever 17
Has a claw shape in a direction perpendicular to the recording paper conveyance direction, and the rotation trajectory of the recording paper return levers 17 and the leading end thereof is an arc-shaped portion of the paper feed roller 14 during recording paper single sheet feeding. The recording paper return levers 17 extend from the second posture state to the first posture state at the inner side (in the direction of the center of the paper feed roller 14) from the outer peripheral surface of the recording paper return lever 17. An operation is performed to lift the uppermost recording sheet S1 being fed, and the recording sheets S to be multi-fed from the next position onward.
2 is removed and pushed back to the recording paper tray 8 side.

The recording paper return levers 17, 17 are finally located in the lever access holes of the recording paper front end abutting plate 22, and are substantially flush with the plate 22, as shown in FIG. The claw-shaped portion 17a on the side returns to the first posture state in which it protrudes above the upper surface of the recording paper transport guide 23 from the upper edge of the recording paper leading end abutting plate 22.

The recording paper return levers 17 which have returned to the first posture state prevent double feeding of the next or subsequent recording paper S2 due to the movement of the uppermost recording paper S1 being continuously conveyed.

Then, the uppermost recording sheet S being continuously conveyed
After the trailing edge of the sheet 1 has passed under the sheet feeding roller 14, the next sheet feeding start signal enters the control circuit, so that the same apparatus operation cycle as described above is executed, and the one sheet separation and feeding of the next recording sheet S2 is performed. Is made.

The recording paper return levers 17, 17 which are controlled to switch between the first and second postures, prevent double feeding of recording papers other than the recording paper S1 that is being separated and fed, and return to the first posture state. Thus, the replenishment and the setting operation of the recording paper to the recording paper tray 8 can be performed reliably and easily, and the quality defect due to the conveyance failure such as the double feeding and the non-feeding can be eliminated.

C) Jam Processing in Paper Feeding System B When the paper feeding system B detects the occurrence of paper jam in the recording paper during feeding by a jam detecting means (not shown), the operation of the apparatus is stopped.

FIG. 13A shows an arc-shaped portion of the paper feed roller 14 where the recording paper in the middle of one-sheet separation feeding has jammed and the jammed recording paper Sa has stopped rotating, and the frictional separation roller 15.
3 shows a state in which the auxiliary roller 16 is sandwiched between nip portions.

In this state, if the jam recording paper Sa is pulled from the recording paper tray 8 side and is to be pulled out and removed from the nip portion, the paper feed roller 14 is
Because the urging force of the auxiliary roller 5 and the auxiliary roller 16 is obtained, a considerable force is required to pull out the jam recording paper Sa from the nip portion. In the worst case, the jam recording paper Sa is torn.

In the apparatus of this embodiment, as described with reference to FIG.
The unit 37 is fed by the push-down member 40 against the urging spring 38 in conjunction with the swinging operation of the recording paper tray 8, which is a vertically swingable sheet material loading table, in the overstroke range α. In the above case, as shown in FIG. 13B, the upper surface of the stacked recording paper S on the tray 8 is pressed against the urging spring 19 in the case described above. The tray 8 by pressing F with your fingers.
The downwardly projecting edge 8c of the front end of the unit abuts against the inner surface of the fixed base plate 18 and is rotated downward until it is received.
7 and is pressed against the receiving plate 37a to push up the unit 37 and lower the unit 37 against the urging spring 38.

As a result, the pressure contact between the frictional separation roller 15 and the auxiliary roller 16 against the arcuate portion of the paper feed roller 14 is released, and the frictional separation roller 15 and the auxiliary roller 16 are separated from the arcuate portion of the paper supply roller 14. , Jam recording paper S
The state in which “a” is sandwiched between the arc-shaped portion of the paper feed roller 14 and the nip formed by the friction separating roller 15 and the auxiliary roller 16 in the rotation stopped state is released.

Therefore, in this state, the jam recording paper S
By pulling out a, the jam recording paper Sa can be easily removed without any load.

After the jam recording paper Sa has been pulled out and removed, when the pressing F against the recording paper tray 8 is released, the tray 8 is pushed up by the urging spring 19 to rotate upward and stop again at the predetermined standby position. And the push-down member 40 moves upward in conjunction with this so that the unit 3
7 is released, the unit 37 is lifted by the push-up urging spring 38, and the friction separating roller 15 and the auxiliary roller 16 are pressed against the arc-shaped portion of the paper feed roller 14 at a predetermined pressure. Become.

After the jam has been cleared, the apparatus is reset and the paper feeding is performed again.

(3) Other Embodiments 1) The recording means for the recording paper S uses the ink jet recording system in the above embodiment, but the electrophotographic recording system using a toner (laser beam printer) or the ink Naturally, an appropriate recording means such as a thermal transfer recording method using a sheet and a thermal head can be used.

2) In the above embodiment, the recording paper separation operation was performed using the friction separation roller (retard roller) 15 having a torque limiter as a separation member.
As described above, the separation operation of the recording paper may be performed by using the friction pad 100 including the friction portion 101 and the friction portion holder 102 as the separation member. In this example, a normal rubber sheet is used as the friction portion 101.

3) The paper feeder of the present invention is not limited to use as a recording paper feeder in a facsimile apparatus as in the embodiment, but may be used in other image forming apparatuses such as a copying machine, a laser beam printer, and an ink jet printer. Needless to say, it can be effectively used as a sheet material feeding device provided in a sheet feeding device or other sheet material using device.

4) In the image forming apparatus, the sheet material is, for example, a transfer material, a recording paper, a printing paper, an OHP paper, an original, an envelope, a postcard, a card, a film, and the like. The material is not limited to paper, but may be plastic, metal, cloth, or the like.

[0126]

As described above, according to the present invention,
An intended paper feeder which has solved the above-mentioned problems of the conventional paper feeder, that is, a) improved operability of replenishing supply and setting of sheets by a user; There are no conveyance failures such as non-feeding, and the front end of the sheet is not broken or damaged. C) The sheet jam can be easily removed. D) The user can use the product easily, and the quality can be reduced at lower cost. A more improved paper feeder can be obtained.

[Brief description of the drawings]

FIG. 1 is an external perspective model view of a facsimile apparatus as an example of an image forming apparatus provided with a sheet feeding device according to the present invention.

FIG. 2 is a longitudinal sectional side view schematically showing an internal mechanism of the apparatus.

FIG. 3 is a block diagram of a control system of the apparatus.

4A is a perspective model view of a paper feed roller portion of a paper feeding system, and FIG. 4B is a perspective model diagram of a friction separation roller and an auxiliary roller portion provided below the paper feed roller.

FIG. 5 is a schematic plan view of a friction separation roller and an auxiliary roller.

FIGS. 6A and 6B are explanatory views of a mechanism for pressing down a friction separation roller and an auxiliary roller unit.

FIG. 7 is a diagram showing a recording sheet separating / feeding operation process (part 1, waiting for sheet feeding).

FIG. 8 is a diagram illustrating a recording sheet separating / feeding operation process (part 2, at the beginning of sheet feeding).

FIG. 9 is a diagram showing a process of separating and feeding one sheet of recording paper (part 3, when paper feeding is in progress);

FIG. 10 is a diagram showing a recording sheet separating / feeding operation process (part 4, when paper feeding is in progress);

FIG. 11 is a diagram illustrating a process of separating and feeding one sheet of recording paper (No. 5, at the end of one rotation of the feed roller).

FIG. 12 is a diagram showing a process of separating and feeding one sheet of recording paper (No. 6, at the end of one rotation of the feed roller).

FIGS. 13A and 13B are explanatory diagrams of recording paper jam occurrence and jam processing.

FIG. 14 is a model diagram of a main part of an apparatus using a friction pad as a separating member.

[Explanation of symbols]

 Reference Signs List A reading system B paper feeding system C recording system 8 recording paper tray 14 paper feeding roller 15 friction separation roller (retard roller) 16 auxiliary roller 17 recording paper return lever 37 friction separation roller / auxiliary roller unit 40 push-down member

Claims (11)

[Claims] 1. An automatic sheet feeding apparatus comprising: a sheet member stacked in a stacked state on a sheet material mounting table; In the sheet feeding device, a unit that releases a contact pressure between a feeding member and a separating member of the separating / feeding unit; and the sheet material stacking table presses the loaded sheet material at a predetermined pressure with the separating / feeding unit. Means for canceling the contact of the loaded sheet material by the sheet material mounting table with respect to the feed member. A sheet feeding device configured such that, when a sheet material stacking table is pressed in a direction in which a contact of a placed sheet material with respect to the feeding member is released, the feeding member and the separating member are separated from each other in conjunction with the pressing. 2. The sheet feeding device according to claim 1, wherein the sheet material loading table is rotatably supported by the pressing operation in a direction away from the sheet feeding member from a sheet material loading position. 3. The sheet feeding device according to claim 1, further comprising a conveyance assisting member that faces the sheet feeding member and presses the sheet feeding member downstream of the sheet feeding member in the sheet conveying direction. apparatus. 4. The sheet feeding device according to claim 3, wherein the transport assisting member is configured to be separated from the feeding member by the pressing operation of the sheet material stacking table. 5. The sheet feeding device according to claim 1, wherein the feeding member is a feeding roller, the separating member is a separating roller, and the transport auxiliary member is an auxiliary roller. . 6. The sheet feeding roller serving as the feeding member having a half-moon shape, whereby the contact of the sheet feeding roller with the separation roller serving as the separating member is released. A paper feeder according to claim 1. 7. The sheet feeding device according to claim 1, further comprising a sheet material double feed prevention member that can move into and out of the sheet material conveying path so as to be able to move freely. 8. A position where the sheet material accompanying double feed preventing member protrudes into the sheet material conveyance path is substantially the same as a front end abutting portion of a sheet material stacked on the sheet material stacking table. The sheet feeding device according to claim 7, which is a surface. 9. A position of the sheet material accompanying double feeding prevention member which is retracted from the sheet material conveyance path is downstream of the separation feeding means in the sheet material feeding direction and a sheet material conveyance guide surface. The sheet feeding device according to claim 7, wherein the sheet feeding device is located at a position that does not protrude further. 10. The apparatus according to claim 1, wherein a period from when the loaded sheet material on said sheet material stacking table abuts on said feeding member to when said feeding member of said separation feeding means comes into contact with said separating member. The sheet feeding device according to claim 7, wherein the sheet material double feed prevention member is located at a position where the sheet material double feeding prevention member protrudes into the sheet material conveyance path. 11. The sheet material mounting table is arranged such that the leading end of the sheet material stacked on the sheet material mounting table is mounted by its own weight to the vicinity of the separation feeding means. 2. The device according to claim 1, wherein the angle is set at an angle.
11. The paper feeding device according to any one of claims 10 to 10.