JP2002068503A - Paper sheet feeding device, and recording device provided with same device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeding device capable of securely separating the sheets, and stably feeding the sheet. SOLUTION: In this sheet feeding device, the sheet P1 positioned at the uppermost part of the sheet P stocked in a hopper 3 is only taken to be fed. It is provided with the hopper 3 to preliminarily stock a plurality of sheets of paper P, a feed roller 3 applied to the sheet P1 at the uppermost part, and press the stocked sheet P for feeding it, a sheet separating member 4 to separate the sheets P1 positioned at the uppermost part from the other sheet laminated with this, and a sheet returning member 42 to return the other sheet double-fed with it to the hopper 3. The sheet separating member 4 may be composed of separation protrusions 4A or separation friction members 4B axially disposed on both sides of the sheet feeding roller 2 to be close to it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feeder used for a recording device such as a printer, for taking out and feeding only the uppermost sheet of paper stocked on a hopper, and particularly to a sheet feeder located at the uppermost position. The present invention relates to a sheet feeding device capable of reliably and stably separating a sheet to be separated from another sheet, and a recording apparatus including the sheet feeding device.

[0002]

2. Description of the Related Art It is the most demanded for a sheet feeding device to reliably take out sheets stocked on a hopper one sheet at a time and to stably feed the sheets while maintaining a predetermined posture without deforming the sheets. It is an important and basic function. Among them, separation pawls are provided at the left and right corners in the paper width direction at the paper start end side as a structure that separates the topmost paper one by one, and those that mechanically separate the paper by these separation claws are already on the market. Are provided.

[0003]

However, in the case where the paper is mechanically separated by using a separation claw, the front corner of the paper is bent when the paper is taken out from the hopper. However, the fold may cause the paper to be discharged without returning to its original shape, cause the skew of the paper in the paper feeding process due to the fold, or cause a paper jam.

Further, the structure using the separation claw is easily affected by a slight difference in the dimensions of the paper, a curl, and a difference in the thickness of the paper. Often there was.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sheet feeding apparatus capable of reliably separating sheets and performing a stable sheet feeding operation, and a recording apparatus including the sheet feeding apparatus.

[0006]

According to a first aspect of the present invention, there is provided a sheet feeder for picking up and feeding only the uppermost sheet of sheets stored on a hopper. A stock unit including a hopper capable of stocking a plurality of sheets, a paper feed roller acting on the uppermost sheet and pressing the stocked sheet to feed the sheet, and a sheet located at the uppermost part A paper separating member that separates the other paper stacked therefrom, and a paper returning member that returns the other multi-fed paper to the hopper,
The paper separating member is a separating protrusion disposed near both sides in the axial direction of the paper feed roller.

According to the present invention, the other sheet adhered to the uppermost sheet and taken out of the sheet comes into contact with the separating projection to be fed by symmetrical forces on both axial sides of the sheet feeding roller. Entry into the paper roller is prevented. Therefore, reliable separation from the next sheet to be fed can be performed.

A paper feeder according to a second aspect of the present invention is a paper feeder that takes out and feeds only the uppermost sheet of the sheets stocked on the hopper, and is capable of stocking a plurality of sheets. , A paper feed roller that acts on the topmost sheet and presses and feeds the stocked paper, and separates the topmost sheet from other sheets stacked on it. A paper separating member, and a paper returning member for returning another multi-fed paper to the hopper, wherein the paper separating member is a friction member for separation arranged near both sides in the axial direction of the paper feed roller. It is characterized by the following.

According to the present invention, the other sheet adhered to the uppermost sheet and taken out is symmetrical on both sides in the axial direction of the sheet feeding roller due to the resistance due to the frictional force of the separating friction member. The force prevents the paper feed roller from entering. Therefore, reliable separation from the next sheet to be fed can be performed.

According to a third aspect of the present invention, in the sheet feeding apparatus according to the first or second aspect, the sheet feeding roller includes two sheet feeding rollers disposed near both ends of the sheet width. The paper separating member is provided near the outside of the two paper feed rollers. According to the present invention, skew can be hardly caused because the posture of the next sheet to be fed is more easily maintained by the action of the two sheet feeding rollers, the occurrence of paper jam due to the skew is prevented, and the stacked sheets They can be more reliably separated from each other.

According to a fourth aspect of the present invention, in the sheet feeding apparatus according to the first or second aspect, the sheet feeding roller includes two sheet feeding rollers disposed near both ends of the sheet width. The paper separating member is provided near the inside of the two paper feed rollers. According to the present invention, skew can be hardly caused because the posture of the next sheet to be fed is more easily maintained by the action of the two sheet feeding rollers, the occurrence of paper jam due to the skew is prevented, and the stacked sheets They can be more reliably separated from each other.

According to a fifth aspect of the present invention, in the sheet feeding apparatus according to any one of the second to fourth aspects, the separating friction member includes a rib-shaped separating friction piece for a sheet feeding roller. It is characterized by being constituted by arranging a plurality of pieces in the axial direction. According to the present invention, the stoppage force acting in the sheet width direction caused by the rib-shaped separating friction pieces arranged side by side prevents the sheet located at the top in the middle of sheet feeding from being shaken or slipped, and the sheet attitude Is fed in a more stable state.

According to a sixth aspect of the present invention, in the paper feeder according to any one of the second to fourth aspects, the separating friction member has a rib-like shape in the axial direction of the paper feed roller. It is an integrated separation pad having a plurality of friction protrusions arranged side by side. According to the present invention, the stoppage force acting in the sheet width direction caused by the rib-shaped separation protrusions arranged side by side prevents the sheet located at the uppermost part in the middle of sheet feeding from being shaken or slipped, and the posture of the sheet. Is fed in a more stable state.

According to a seventh aspect of the present invention, there is provided a recording apparatus such as a printer, comprising the paper feeder according to any one of the first to sixth aspects. According to the present invention,
Since a reliable and stable paper feeding operation is guaranteed, paper jams in the paper feeding process and deviations in the posture of the paper are eliminated.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional side view of an ink jet printer which is one of recording apparatuses to which a sheet feeding apparatus according to the present invention is applied. FIG. 2 is a plan view (a) and a side view (b) of a sheet feeding device including a sheet feeding unit 30 including a sheet feeding roller 2 and a separation unit 40 including a sheet separating member 4, and FIG. 7A illustrates a standby state before the start of sheet feeding, and FIG. 7B illustrates a state of sheet feeding with a pair of sheet feeding rollers. FIG. 4A is a plan view showing an embodiment of the arrangement of the paper return member and the paper separation member, and a side view corresponding to the left end thereof is shown. FIG. It is a top view showing other embodiments of arrangement of a paper separation member, and a side view corresponding to the left end is shown. FIG. 5 is a perspective view when the sheet feeding unit and the separation unit are assembled.

As shown in FIG. 1, an ink jet printer 1 having a paper feeder according to the present invention uses a paper separating member 4 to feed a plurality of sheets P stocked on a hopper 3 by rotation of a paper feed roller 2. 2, the paper is separated one by one, fed to the transport roller 6 along the paper guide 5, skewed, sent to a print area in accordance with print timing, and fed to a carriage 8 on which a printhead 7 is mounted. A configuration is provided in which printing is performed by reciprocating movement in the sub-scanning direction and then discharged by the discharge roller 9.

In this embodiment, a paper support 21 is attached to the housing 10 of the ink jet printer 1, and an edge guide 22 for regulating the side edge of the paper P supported by the paper support 21 is provided in the housing 10.
Is slidably provided. A hopper 3 is movably provided between the edge guide 22 and the paper feed roller 2, and when the hopper 3 is advanced, the paper separating member 4 presses the paper P 1 located at the uppermost position against the paper feed roller 2. Separate and feed.

First, individual members constituting the sheet feeding unit 30 and the separation unit 40 shown in FIG. 2 will be described in detail. In FIG. 2, a paper feed unit 30 has a roller shaft 32 rotatably supported by a bearing 31 a of a roller holder 31, and the paper feed roller 2 is provided on the roller shaft 32. Further, the roller shaft 32 is provided with a hopper drive cam 34 constituting a hopper cam mechanism for operating the forward and backward movement of the hopper 3 and a roller drive gear 35 for rotationally driving. The roller drive gear 35 is linked to a drive gear of a paper feed motor (not shown) via an intermediate transmission gear.

The paper feed roller 2 comprises an arc portion 2a and a flat portion 2c as shown in FIG. 2 (b). The surface of the arc portion 2a has a friction in order to enhance grip when feeding the paper P. The member is attached. The circular arc portion 2a has a protruding circular arc portion 2b which travels with respect to the flat portion 2c to increase the overall circular arc length. Projecting arc part 2b
Indicates that even if the amount of paper loaded on the hopper 3 changes,
The sheet P works so as to be reliably transported.

When there is one sheet of paper P in the hopper 3,
The time required for the hopper 3 to move forward from the retracted position and for the paper P to contact the paper feed roller 2 is the longest. That is,
Since the paper feed roller 2 rotates by a predetermined angle before the paper P comes into contact with the paper P, the lengths of the arc portion 2a and the protruding arc portion 2b are determined from the position at which the paper P comes into contact with the paper feed roller 2
It is set so that it can move the distance to the position where it reaches. Thus, the flat portion 2c of the paper feed roller 2
By providing the protruding arc portion 2b on the side, the entire arc portion 2a can be lengthened without increasing the diameter of the paper feed roller 2, and the apparatus can be downsized.

The separation unit 40 has a paper guide 5 on a front inclined surface of a frame 41 having a mountain-shaped cross section extending in the sheet width direction of the ink jet printer 1, and a hopper 3 is disposed on the rear inclined surface. A paper return member 42 is disposed at the top along the ridge line portion, and the base end thereof is rotatably supported along the ridge line portion. The hopper 3 is attached so as to be able to advance and retreat along the inclined surface of the frame 41 with one end in the paper width direction of the inkjet printer 1 as a fulcrum.

Also, on the back near the other end of the hopper 3,
A hopper spring (not shown) is provided between the frame 41 and the hopper 3, and urges the hopper 3 in a direction along the rear inclined surface of the frame 41. A sheet (not shown) formed of a high friction material is attached to the surface of the hopper 3 on the sheet P side in accordance with the position of the sheet separating member 4.

As shown in FIG. 3, the paper return member 42 is rotatably mounted by fitting a base end 42b formed in a bearing structure to a shaft portion of the frame 41.
The paper separation member 4 is provided on the paper contact surface 42c of the paper return member 42 so as to be spaced apart therefrom.

At a free end opposite to the base end 42b, a bank portion 42d slightly extending obliquely upward from the paper contact surface 42c is formed at a portion other than the mounting portion of the paper separating member 4, and this bank portion is formed. Reference numeral 42d functions to reliably catch the leading end of the sheet and push it back to the hopper 3 when returning the sheet.

The paper guide 5 is formed with a notch 46 having substantially the same shape as the paper return member 42. The notch 46 is formed in the notch 46 when the paper return member 42 stands up (the state shown in FIG. 3A). When the paper guide 5 rotates and falls down (as shown in FIG. 3B) against the urging force of the urging spring 47, the paper guide 5
And become flush. The biasing spring 47 is formed of, for example, a torsion coil spring, and is disposed on the back side of the frame 41. One end of the urging spring 47 is locked to the back surface of the paper return member 42, and the other end is locked to the frame 41, and urges the paper return member 42 to stand (the state shown in FIG. 3A). .

The upright position of the paper return member 42 rises substantially vertically, and prevents the paper at the time of setting from inadvertently entering the paper transport path. In this upright state, since the paper return member 42 is located outside the rotation locus of the roller surface of the paper feed roller 2, no rotational power can be given. Therefore, in order to position the portion for applying the rotating power to the paper return member 42 within the rotation trajectory of the roller surface of the paper feed roller 2, a small cam and a cam follower (not shown) are initially set at the initial rotation of the paper feed roller 2. The paper return member 42 is initially rotated by a predetermined angle in conjunction with the rotation of the paper feed roller 2 used. Thereafter, the paper feed roller 2 comes into contact with the paper feed roller 2, and the paper return member 42 can be smoothly and smoothly rotated by the pressing force of the paper feed roller 2.

In the above-mentioned configuration, the paper P stored in the stock portion on the hopper 3 is fed in the axial direction in the paper width direction and the paper feed roller 2 is arranged at a position opposed to the paper feed roller 2. When the sheet P is fed only by the plate, the sheet P is misaligned, and when the sheet is conveyed, a skew occurs and a sheet jam is easily generated. Therefore, in the present invention, in order to solve the above-mentioned problem caused by the conventional system in which the friction plate is arranged only at the position facing the paper feed roller 2, the structure and arrangement of the paper separating member described below are adopted.

Hereinafter, the characteristic configuration of the sheet feeding device 20 of the present invention will be described. The paper feeding device 20 is configured to output the uppermost sheet P1 of the sheets P stocked on the hopper 3.
It has the role of taking out only and feeding paper. More specifically, a stock unit having a hopper 3 for stocking a plurality of sheets of paper P in advance, a paper feed roller 2 acting on the uppermost sheet P1 to press and feed the stocked paper, The paper P1 includes a paper separating member 4 for separating the positioned paper P1 from the other paper P2 laminated thereon, and a paper return member 42 for returning the multiply fed other paper P2 to the hopper 3.

A plurality of paper separating members 4 are provided in the axial direction of the paper feed roller 2. In the embodiment shown in FIG. 4A, the separating projection 4A having a triangular cross section constitutes the paper separating member 4. are doing. Each of the separation protrusions 4A is disposed near each of both sides in the axial direction with the sheet feed roller 2 interposed therebetween.

As shown in FIG. 4B, the paper separating member 4 is made of, for example, synthetic rubber or the like, and is a separating friction member made of a material having a friction coefficient larger than the friction coefficient between the papers P. 4B can also be used.

As shown in the plan view of the main part shown in FIG. 6A and the enlarged front view of the main part near the right side, the separating friction member 4B is constituted by a rib-shaped separating friction piece 4C. A plurality of these may be separated from each other in the axial direction of the paper feed roller 2 and juxtaposed, or as shown in a plan view of a main part shown in FIG. Alternatively, the separation friction member 4B may be in the form of an integrated separation pad 4E in which a plurality of rib-shaped separation friction protrusions 4D are arranged in the axial direction of the paper feed roller 2.

By the way, when the separating friction member 4B of the form shown in FIGS. 6A and 6B is adopted, the same grip property as the tread pattern engraved on the tire of the automobile is exhibited. The stopping force against the movement in the paper width direction is increased.

Further, as shown in FIGS. 6 (c) and 6 (d), when another paper feed roller 33 is provided in the axial direction of the paper feed roller 2, it is located near the outside of the two paper feed rollers 2, 33. The paper separating member 4 can be arranged (FIG. 6C), and conversely, the paper separating member 4 can be arranged near the inside of the two paper feed rollers 2 and 33 (FIG. 6D). .

The feed roller 2 is mounted on the roller holder 31 together with the roller shaft 32 and the roller drive gear 35 to form a single unit.
The paper separating member 4, the paper guide 5, and the paper returning member 42 constitute a separate single unit as a part of the frame 41 having a mountain-shaped cross section or by being assembled to the frame 41.

Next, the paper feeding operation will be described. First, a plurality of sheets P are set in a stock section including the paper support 21. The flat portion 2c of the paper feed roller 2 at the home position is substantially parallel to the surface of the paper guide 5 of the frame 41, and the paper return member 42 stands up as shown in FIG. Does not interfere with the When the paper return member 42 is raised, the paper return member 42 is located at a position where the paper transport path between the paper feed roller 2 and the hopper 3 is blocked, and abuts on the leading edge of the paper P when setting the paper, thereby restricting and preventing the paper P from entering. have. On the other hand, the hopper drive cam 34
As a result, the hopper 3 is in a state of being pushed down to the retracted position.

In response to a feed start command, the feed roller 2
Is rotated, first, a small cam (not shown) is
The paper return member 42 is slightly inclined by acting on a cam follower (not shown) of FIG. Paper return member 4
After the paper feed roller 2 is tilted by a predetermined angle, the paper feed roller 2 comes into contact with the surface of the paper return member 42, and the pressing force of the paper return member 42 pushes the paper return member 42 against the urging of the urging spring 47, as shown in FIG. As shown in b), it is turned in the falling direction. During this time, the hopper drive cam 34 acts on a hopper cam follower (not shown) to maintain the hopper 3 at the retracted position. The paper return member 42 reaches the falling position, and then the hopper 3 is moved forward by the urging force of a hopper spring (not shown), contacts the sheet P1 located at the uppermost position, and presses the sheet P1 against the sheet feeding roller 2 side.
The rotation of the paper feed roller 2 starts feeding the paper P1 located at the uppermost position.

At this time, the paper contact surface 4 of the paper return member 42
The paper separating member 4 provided in 2c prevents another paper P2, which has been overlapped and sent, from entering.
Before the leading edge of the sheet reaches the transport roller 6, the hopper drive cam 34 acts on a hopper cam follower (not shown),
The hopper 3 starts descending. When the hopper 3 reaches the retreat position, the raising operation of the paper return member 42 is thereafter performed by the urging spring 4.
It starts with a bias of 7. During this time, the leading end of the uppermost sheet P1 reaches the transport roller 6, and the skew removal and cueing operations are performed.

Subsequently, the raising operation of the paper return member 42 is continued by the urging force of the urging spring 47, and the erecting is completed. During the upright rotation, the other sheet P2 of the double feed, which was accompanied by the sheet P1 positioned at the uppermost position in the previous operation and was prevented from entering by the sheet separating member 4, has a leading end of the sheet returning member 42. , The paper is pushed back toward the hopper 3 and returned to the storage position again. And paper feed roller 2
Is returned to the home position, printing of the topmost sheet P1 is started.

In the above embodiment, the rotating paper return member 4 is used.
This is an example in which the present invention is applied to a paper feeding device provided with a paper feeding device 2. However, the present invention is also applied to a paper feeding device having a structure other than such a structure by providing paper separating members near both sides of a paper feeding roller. Can be done.

[0040]

According to the present invention, when the paper return member is provided on both sides of the paper feed roller or in the case where two or more paper feed rollers are provided, the paper separation member is attached near the outer side or the inner side. Is prevented from entering the paper feed roller, and another paper that has been fed together with the paper located in the paper feed position is reliably prevented from entering the paper feed roller. In addition, the structure is simple, it is possible to keep the product cost low, and there is no mechanical trouble that occurred when using the structure using the conventional separation claw, and it is extremely reliable and stable. Separation can be performed.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view of an ink jet printer which is one of recording devices to which a sheet feeding device according to the present invention is applied.

FIG. 2 is a plan view (a) and a side view (b) of a sheet feeding device including a sheet feeding unit including a sheet feeding roller and a separation unit including a sheet separating member.

FIGS. 3A and 3B are explanatory diagrams illustrating the operation of a paper return member in the separation unit, where FIG. 3A illustrates a standby state before the start of paper feeding;
(B) shows a state at the time of paper feeding with a pair of paper feeding rollers.

FIG. 4A is a plan view showing an embodiment of the arrangement of a paper return member and a paper separation member, and a side view corresponding to the left end thereof is shown; It is a top view showing other embodiments of arrangement of a paper separation member, and a side view corresponding to the left end is shown.

FIG. 5 is a perspective view when the sheet feeding unit and the separation unit are assembled.

FIGS. 6 (a) to 6 (d) are plan views showing other configurations and arrangements of the paper separating member, and FIGS. 6 (a) and 6 (b) are enlarged longitudinal sectional front views of main parts.

[Explanation of symbols]

 Reference Signs List 2 paper feed roller 2b projecting arc part 3 hopper 4 paper separation member 4A separation protrusion 4B separation friction member 4C separation friction piece 4D separation friction protrusion 4E separation pad 6 transport roller 9 discharge roller 10 housing 20 paper feeder REFERENCE SIGNS LIST 30 paper feed unit 31 roller holder 31a bearing part 32 roller shaft 33 other paper feed roller 40 separation unit 41 frame 42 paper return member 42b base end 42c paper contact surface 42d bank part 46 notch 47 urging spring P paper P1 Paper at the top P2 Other paper

Claims (7)

[Claims] 1. A sheet feeder for picking up and feeding only a sheet located at the top of sheets stored on a hopper, comprising: a stock section including a hopper capable of stocking a plurality of sheets; Paper feed roller that acts on the paper to be pressed and feeds the stored paper by pressing it, a paper separating member that separates the topmost paper from other papers stacked on the paper feed roller, A sheet return member for returning another sheet to the hopper, wherein the sheet separation member is a separation protrusion disposed near both sides in the axial direction of the sheet supply roller. 2. A paper feeder for taking out and feeding only the topmost sheet of paper stocked on a hopper, wherein the stocker includes a hopper capable of stocking a plurality of sheets and a topmost sheet. A paper feed roller that acts on the paper and presses the stock paper against it to feed the paper, a paper separating member that separates the topmost paper from other papers stacked on the paper, and a double feed. A sheet return member for returning another sheet onto the hopper, wherein the sheet separation member is a separation friction member arranged near both sides in the axial direction of the sheet supply roller. 3. The paper feed roller according to claim 1, wherein the paper feed roller is composed of two paper feed rollers disposed near both ends of a paper width, and the paper separating member is located outside the two paper feed rollers. A sheet feeding device, which is provided in the vicinity. 4. The paper feed roller according to claim 1, wherein the paper feed roller is composed of two paper feed rollers arranged near both ends of a paper width, and the paper separating member is provided inside the two paper feed rollers. A sheet feeding device, which is provided in the vicinity. 5. The separating friction member according to claim 2, wherein the separating friction member is configured by arranging a plurality of rib-shaped separating friction pieces in the axial direction of the sheet feeding roller. Paper feeder. 6. The separation friction member according to claim 2, wherein the separation friction member is an integrated separation pad having a plurality of rib-shaped separation friction protrusions arranged in the axial direction of the paper feed roller. A sheet feeding device characterized by the above-mentioned. 7. A recording apparatus comprising the sheet feeding device according to claim 1.