KR100419225B1 - automatic document feeder of an office machine - Google Patents

Abstract

According to the present invention, an automatic sheet feeding apparatus of an office equipment includes a frame constituting a document or paper stack, a pickup roller assembly having a pickup roller for picking up the paper loaded in the frame, and a pickup roller arranged in a sheet. A friction pad assembly having a friction pad for separating and supplying, and a fixing part for fixing the friction pad assembly to the frame such that the feeding pressure applied to the pickup roller at the time of pickup is uniformly distributed over the entire width of the pickup roller; . The fixing portion includes a hinge shaft provided in the feeding direction to the friction pad assembly, and a hinge shaft support portion formed opposite the hinge shaft to the frame. According to the present invention, the friction pad assembly can be fixed so that the pressure contact between the friction pad and the pickup roller is uniformly distributed even when the frame is arranged eccentrically and not parallel to the pickup roller due to manufacturing and assembly errors. The document or paper can be prevented from being skewed or meandered.

Description

Automatic document feeder of an office machine

The present invention relates to an automatic document feeder (hereinafter referred to as an automatic document feeder) applied to an office equipment such as a multifunction printer, a fax machine, and the like, and more particularly, a friction that separates the document or sheet into sheets during pickup. The present invention relates to an automatic paper feeding device for an office equipment, which prevents skew or meandering paper feed by allowing the pad to contact the pickup roller with a uniform distribution.

In general, office equipment such as a fax machine, a multifunction printer, and the like include an automatic paper feeder for picking up a document or paper from a paper feed tray or cassette on which a document or paper is loaded and feeding the paper toward a scanning device or a printing device.

Referring to FIG. 1, a scanning device of an office equipment such as a fax machine, a multifunction printer, and the like having a general automatic paper feeder is schematically illustrated. The scanning device is formed on the upper side of one side of the machine, and the scanner 31 reads data from the automatic paper feeder 20 for automatically feeding the document D into the machine, and the originals D transported by the automatic paper feeder 20. ), A white roller 31 'for contacting the document D with the scanner 31, and an ejector for discharging the document D having passed through the scanner 31 and the white roller 31' out of the machine. It consists of 32.

The automatic document feeder 20 for feeding the document D into the machine detects whether the upper and lower frames 1 and 2 and the document D are loaded, which constitute the document feeder on which the document D is loaded. The loading roller detection unit (not shown), the pickup roller assembly 5, which picks up the document D, and the pickup roller assembly 5 are contacted at a predetermined pressure according to the operation of the loading container. D) the original to the friction pad assembly 15 which separates the sheet into pieces, fixing parts 21 and 25 (FIG. 2) for fixing the friction pad assembly 15 to the upper frame 1, and the scanner 31; It has a paper feed roller assembly 29 for conveying ().

As shown in FIG. 2, the pickup roller assembly 5 is a motor gear (not shown) that transmits power from a driving motor (not shown) to pick up the document D according to the operation of the document loading presence detection unit. A first pick-up roller 11 having a first pick-up gear 9 connected thereto, an idle gear 8 meshing with the first pick-up gear 9, and a second pick-up gear 7 meshing with the idle gear 8. And a second pick-up roller 6 having).

Above the second pick-up roller 6, a lever 3 for pressing the picked-up document D in close contact with the circumferential surface of the second pick-up roller 6 is provided by the elastic springs 4 and 4 '. It is fixed to the upper frame (1) to be pressed toward the (6), the leaf spring 12 for pressing the original (D) in close contact with the circumferential surface of the first pickup roller 11 above the first pickup roller (11) The arm 12 'is fixed to the upper frame 1 with a set screw 14 so as to contact the first pickup roller 11.

In addition, the first pick-up roller on which the arm 12 'of the leaf spring 12 is disposed so as to separate and feed the sheets D so that the originals D picked up by the second pick-up roller 6 are not fed several at a time. A friction pad assembly 15 is fixed to the upper frame 1 downstream of the circumferential surface of 11).

The friction pad assembly 15 has a friction pad 19 in contact with the circumferential surface of the first pickup roller 11, and the friction pad 19 has a predetermined pressure and nip with the circumferential surface of the first pickup roller 11. The first and second leaf springs 17 and 18 and the fixing holder 16 fixes and supports the friction pad 19 and the first and second leaf springs 17 and 18 to be pressed in close contact with each other. It is composed. The friction pad 19 and the first and second leaf springs 17 and 18 are fixed to the fixing holder 16 by fastening pin assemblies 23 and 23 'composed of fastening pins and fastening pin holders.

The friction pad 19 is formed of a rubber having a sliding film attached to a lower surface of the first pickup roller 11 that does not contact the circumferential surface of the first pickup roller 11, and the first leaf spring 17 removes the friction pad 19. It extends longer than the 2nd leaf spring 18 so that it may be pressed against the circumferential surface of the 1st pick-up roller 11, and is pressed.

The fixing portions 21 and 25 accommodate the first and second hinge protrusions 22 and 22 'and the first and second hinge protrusions 22 and 22' formed at both ends of the fixing holder 16 upstream. An upper fixing portion 21 having a hinge groove 24 formed in the upper frame 1 and corresponding to the first and second hinge protrusions 22 and 22 ', and formed at a center in the feeding direction downstream of the fixing holder 16; It consists of a hook 27 and a lower fixing portion 25 having a hook receiving hole 26 corresponding to the hook 27 in the upper frame 1 to be locked with the hook 27.

The paper feed roller assembly 29 feeds the paper feed roller 30 disposed downstream of the first pick-up roller 11 in the feeding direction so as to be operated by the motor gear, and the document D fed by the first pick-up roller 11. It consists of a pressure roller 30 'which presses on the circumferential surface of the paper feed roller 30.

Referring to FIGS. 1 and 2, the operation of the automatic sheet feeding unit 20 of the conventional scanning apparatus configured as described above is as follows.

First, in order to transfer or copy an original D, when a plurality of originals D are loaded between the upper and lower frames 1 and 2 constituting the original stacker, the original D is lowered by its own weight. By sliding down to operate the document presence detection unit (not shown), the controller applies power to the driving motor to counterclockwise the first pickup gear 9 and the first pickup roller 11 connected to the series of motor gears. Rotated. Therefore, the counterclockwise rotational force of the first pick gear 9 is transmitted to the second pick gear 7 and the second pick roller 6 through the idle gear 8.

Accordingly, the second pick-up roller 6 is rotated in the counterclockwise direction, and the originals D only have some originals D positioned downward while some of the originals D positioned upward by the lever 3 are blocked. It is conveyed toward the 1st pickup roller 11 by the 2nd pickup roller 6.

When the originals D picked up by the second pick-up roller 6 reach the first pick-up roller 11, the documents D are picked up by the arm 12 'of the leaf spring 12 and picked up first. While being in close contact with the circumferential surface of the roller 11, it is pushed by the first pickup roller 11 in the feeding direction again.

At this time, since the friction pad 19 made of rubber is in close contact with the upper portions of the documents (D) to be fed, the bottommost of the plurality of documents (D) fed by the frictional resistance of the friction pad 19 is applied. 1 Only the document D in contact with the circumferential surface of the pickup roller 11 is fed. At this time, the frictional resistance of the friction pad 19 is applied to all of the fed documents D, but the frictional contact force of the first pickup roller 11 is applied to the original document D at the bottom of the friction pad 19. Since the action greater than the frictional resistance, only the lowermost document (D) is fed through the friction pad 19 to be fed in the feeding direction.

In addition, at this time, since a sliding film having a small frictional resistance is attached to the bottom surface of the friction pad 19 that is not in contact with the first pick-up roller 11, a plurality of papers are fed along the circumferential surface of the first pick-up roller 11. The front end portions of the long documents D are smoothly fed to the contact point between the first pickup roller 11 and the friction pad 19 while preventing jams from being caught on the bottom surface of the friction pad 19.

After the document D is separated into sheets by the frictional force with the friction pad 19, and reaches the document entry detection sensor (not shown) located upstream of the feed roller 30, the start button for transmission or copying. When the counting time is reached or the document D reaches the paper feed roller 30, the paper feed roller 30 transfers the paper D to the scanner 31 by the motor gear.

Thereafter, the document D is passed between the scanner 31 and the white roller 31 'by the paper feed roller 30, and the scanner 31 reads the data of the original. After the reading of the data is completed, the document D is discharged to the outside of the apparatus by the discharge unit 32.

However, the conventional automatic sheet feeder 20 acting in this way is adapted to allow the friction pad 19 to come into contact with the circumferential surface of the first pickup roller 11 at a predetermined pressure. Two upper and lower one portions of the friction pad assembly 15 are fixed to each other through the second hinge protrusions 22 and 22 'and the hooks 27 so as not to flow.

Therefore, in the conventional automatic sheet feeder 20, when the structural deformation of the upper frame 1 occurs due to manufacturing and assembly tolerances, bending of parts, and the like, the upper frame 1 may be a circle of the first pickup roller 11. There was a possibility of being arranged eccentrically rather than being kept parallel to the main surface. In this case, the friction pad 19 fixed to the upper frame 1 cannot maintain a uniform contact pressure over the entire width of the first pickup roller 11 when picking up the original.

When the friction pad 19 fails to apply a uniform contact pressure against the first pick-up roller 11, the first pick-up roller 11 generates a torsional moment with respect to the original D at the time of pick-up. A problem arises in that (D) is skewed or meanderedly fed.

The present invention has been made to solve the above problems, the main object of the present invention is that the friction pad and the pick-up roller during pickup even if the upper frame is arranged eccentrically and not parallel to the friction pad due to manufacturing and assembly errors The present invention provides an automatic paper feed apparatus for an office equipment that prevents skew or meander feeding of a document or paper by fixing a friction pad so that contact pressure is uniformly distributed.

1 is a conceptual diagram of a general scanning device applied to an office equipment such as a multifunction printer, FAX, and the like.

Figure 2 is a partial cutaway perspective view of a conventional automatic sheet feeder.

3 is a side cross-sectional view of an automatic paper feeder according to the present invention.

4 is an enlarged perspective view of a part of the automatic sheet feeder shown in FIG.

5 is an exploded perspective view of the friction pad assembly of the automatic sheet feeder shown in FIG. 3.

* Description of the symbols for the main parts of the drawings *

1, 101: upper frame 2, 102: lower frame

3, 103: lever 5, 105: pickup roller assembly

6, 106, 11, 111: pickup roller 15, 115: friction pad assembly

16, 116: fixed holder 19, 119: friction pad

20, 120: automatic feeder 22, 22 ': hinge protrusion

24: hinge groove 26: hook receiving groove

27: hook 29, 129: feed roller assembly

31: Scanner 31 ': White roller

32: outlet 120: hinge shaft

125: fixing part 126, 127: protrusion

126 ', 127': settling groove

In order to achieve the object of the present invention as described above, the present invention relates to a frame constituting a document or paper stack, a pickup roller assembly having at least one pickup roller for picking up the paper loaded in the frame, and the pickup roller In an automatic paper feeder of an office equipment such as a FAX machine, a multifunction printer, etc. including a friction pad assembly having friction pads arranged to separate and feed sheets of paper, the pick-up may be carried out even if the frame is eccentrically arranged. Provided is an automatic paper feed apparatus for an office equipment including fixing means for fixing the friction pad assembly to the frame such that the contact pressure applied to the pickup roller by the friction pad is uniformly distributed over the entire width of the pickup roller.

In a preferred embodiment, the fixing means comprises a hinge axis installed in the feeding direction on one of the frame and the friction pad assembly, and a hinge axis formed opposite the hinge axis on the other of the frame and the friction pad assembly to pivotally fix the hinge axis. It consists of supports. The hinge shaft consists of a rod which is formed in the center of the friction pad assembly and has an end projecting upstream and downstream of the feeding direction, and the hinge shaft support is perpendicular to the feeding direction from the frame so as to receive and rotate the end of the rod. It is preferable to constitute a projection having a seating groove which protrudes and is formed correspondingly to the end of the rod.

Optionally, the hinge axis consists of a rod formed in the center of the friction pad assembly,

The hinge shaft support is preferably composed of at least one seating groove formed to rotatably support the rod on the face of the frame opposite the face of the friction pad assembly having the rod formed thereon.

Hereinafter, with reference to the accompanying drawings, the automatic paper dispenser of the office equipment according to a preferred embodiment of the present invention will be described in detail.

Although the automatic sheet feeder of the present invention can be used to feed originals and / or paper both in the case of configuring the scanning device and the printing device independently of each other in an office equipment such as a fax machine and a multifunction device, and in the case of configuring them to be used in combination with each other, In the following description, only originals are supplied from the scanning apparatus for convenience of description.

The scanning apparatus to which the automatic sheet feeding apparatus of the present invention is applied, as described with reference to FIG. 1, is a scanner for automatically reading data from an automatic sheet feeding apparatus 120 for automatically feeding an original, and an original sheet fed by the automatic sheet feeding apparatus 120. (Not shown), and a discharge device (not shown) for finally discharging the document passing through the scanner to the outside of the machine.

3 and 4, the automatic sheet feeder 120 of the present invention detects whether the document is loaded, the upper and lower frames (101, 102) constituting the document stacking table, the document loading status (Not shown), the friction pad which separates the document into pieces by frictional force by contacting the pickup roller assembly 105 and the pickup roller assembly 105 at a predetermined pressure in order to pick up the document according to the operation of the document loading presence detection unit. The assembly 115, a high-speed for fixing the friction pad assembly 115 to the upper frame 101 so that the paper feed pressure applied to the pickup roller assembly 105 is uniformly distributed with respect to the pickup roller assembly 105. And a paper feed roller assembly 129 for feeding the document D toward the scanner.

A lever 103 for pressing the original against the circumferential surface of the second pickup roller 106 and a leaf spring 112 for pressing the original D against the circumferential surface of the first pickup roller 111. Detailed configurations of the upper frame 102, the lower frame 102, the pickup roller assembly 105, the friction pad assembly 115, the paper feed roller assembly 129, and the like, are described in detail with reference to FIG. As the same as that of, the detailed description will be omitted here.

The fixing part 125 for fixing the friction pad assembly 115 to the upper frame 101 includes a hinge shaft 120 installed in a feeding direction on the upper surface of the upper frame 101, and a hinge shaft on the upper frame 101. And hinge axis supports 126, 127 formed opposite to 120.

As shown in FIGS. 4 and 5, the hinge shaft 120 is formed in the feeding direction at the center of the upper surface of the fixed holder 116 of the friction pad assembly 115 and protrudes upstream and downstream of the feeding direction 121. , 122).

The hinge shaft supports 126 and 127 protrude upwardly from the upper frame 101 and receive the end portions 121 and 122 of the hinge shaft 120 so as to be rotatable and supported, respectively. And protrusions 126, 127 having seating grooves 126 ', 127' formed correspondingly to the ones 121, 122, respectively.

Optionally, the hinge shaft is formed in the feeding direction only at the center of the upper surface of the fixing holder 116 of the friction pad assembly 115, instead of the rod having the end portions 121 and 122 protruding upstream and downstream of the feeding direction (not shown). And the hinge shaft support portion constitutes the hinge shaft at the lower surface of the upper frame 101 instead of the protrusions 126 and 127 having the mounting grooves 126 'and 127' protruding upward from the frame 101. It may also consist of at least one or more seating grooves (not shown) that are configured to pivotally support the rod.

As described above, the fixing part 125 of the automatic sheet feeder 120 of the present invention is partially deformed due to manufacturing and assembly errors, so that the upper frame 101 is not parallel to the first pickup roller 111, and is eccentric to the left and right. Even if it is arranged so that the friction pad assembly 115 is fixed to rotate left and right in the feeding direction through the hinge shaft 120 and the seating grooves (126 ', 127'), the first pickup roller 111 when picking up the document The contact pressure of the friction pad 119 acting on) is uniformly distributed over the entire width of the first pickup roller 111.

The operation of the scanning device to which the automatic sheet feeder 120 of the present invention configured as described above is described in detail with reference to FIGS. 3 and 4 as follows.

First, when a plurality of originals are stacked between the upper and lower frames 101 and 102 in order to transmit or copy the originals, the originals slide down by their own weight to operate the document presence detector (not shown). As described above with respect to the conventional automatic sheet feeder 20, some documents are conveyed toward the first pickup roller 111 by the second pickup roller 106 and the lever 103.

When the originals picked up by the second pick-up roller 106 reach the first pick-up roller 111, the picked-up documents are first picked up by the arm 112 'of the leaf spring 112. While being in close contact with the circumferential surface of the first pickup roller 111 is pushed in the feeding direction again. At this time, since the friction pad 119 made of rubber is in close contact with the upper part of the documents to be fed by the fixing unit 125, the first of a plurality of documents fed by the frictional resistance of the friction pad 119 is applied. Only the bottommost document D in contact with the surface of the pickup roller 111 is fed. In this case, since the fixing part 125 fixes the friction pad 119 so as to rotate slightly from side to side from the center of the feeding direction through the hinge shaft 120 and the seating grooves 126 'and 127'. The contact pressure of the friction pad 119 on the entire width of the first pickup roller 111 becomes uniform, so that the upper frame 101 is slightly eccentric with respect to the circumferential surface of the first pickup roller 111. Even if arranged, the torsional moment acting on the original is absorbed by the fixing portion 125, and skew feeding is prevented.

Subsequently, the document separated into sheets by the friction pad 119 is a document entry sensor (not shown) located upstream of the paper feed direction of the paper feed roller 130 as described above with respect to the conventional automatic paper feed device 20. ), And are fed to the scanner by the feed roller 130 and the pressure roller 130 ', and the data is read out from the scanner and then discharged to the outside of the machine by the discharge device.

As described above, the automatic feeding device of the office equipment according to the present invention is fixed so that the friction pad assembly can be rotated left and right with respect to the feeding direction, so that the upper frame is not parallel to the pickup roller due to manufacturing and assembly errors. Even if it is arranged slightly eccentrically, the pressure at which the friction pad contacts the second pickup roller at the time of pick-up is uniformly distributed, whereby the effect of preventing the paper or paper from being skewed can be obtained.

In the above, specific preferred embodiments of the present invention have been illustrated and described. However, the present invention is not limited to the above-described embodiments, and any person having ordinary skill in the art to which the present invention pertains without departing from the scope of the present invention as claimed in the claims may make various modifications and variations. Would be possible.

Claims (4)

A frame constituting the original or paper stack, a pickup roller assembly having at least one pickup roller for picking up and feeding the paper loaded in the frame, and a friction arranged to separate and feed the sheet by sheet with respect to the pickup roller. In the automatic paper feeder of the office equipment, such as FAX, multifunction machine, etc. including a friction pad assembly having a pad, And fixing means for fixing the friction pad assembly to the frame such that the contact pressure exerted on the pickup roller by the friction pad at the time of pickup is evenly distributed over the entire width of the pickup roller even when the frame is arranged eccentrically and not parallel to the pickup roller. Automatic paper feeding device of the office equipment characterized in that. The method of claim 1, wherein the fixing means, A hinge shaft installed in a feeding direction on one of the frame and the friction pad assembly; And And a hinge shaft support portion formed opposite to the hinge shaft on the other of the frame and the friction pad assembly to secure the hinge shaft to be rotatable. The method of claim 2, The hinge axis includes a rod formed in the feeding direction in the center of the friction pad assembly and having an end projecting upstream and downstream of the feeding direction; The hinge shaft support portion includes a projection having a seating groove projecting perpendicularly to the feeding direction from the frame and supporting the end of the rod so as to be rotatable and formed correspondingly to the end of the rod. . The method of claim 2, The hinge axis includes a rod formed in the feeding direction at the center of the friction pad assembly; The hinge shaft support unit includes at least one seating groove formed to rotatably support the rod on the surface of the frame opposite the surface of the friction pad assembly having the rod.