JP3349564B2 - Paper feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed rotator for feeding the lowermost or uppermost paper of a stacked paper sheet, and a paper feed rotator whose corner is pressed against the paper feed rotator to carry out double feed of paper. A friction member for preventing the rotation, and a pair of conveyance rollers provided on the downstream side in the sheet conveyance direction of the sheet rotation unit. When the sheet fed by the pair of conveyance rollers is clamped, the sheet rotation unit is The present invention relates to a paper feeder for stopping the driving of the sheet feeder and conveying the sheet by the conveying force of the conveying roller pair.

[0002]

2. Description of the Related Art A paper feeder of the above-mentioned type is known, and is attached to a printer, a copying machine, a facsimile, a printing machine and the like. FIG. 5 shows a conventional example of this type of paper feeder.

In FIG. 5, a friction member 1 is pressed against a paper feed roller 2 by a pressing means (not shown). A pickup roller 3 is provided on the upstream side in the paper feed direction, and a transport roller is provided on the downstream side. Pair 5 is provided. The loaded paper 6 to be fed is pressed against the pickup roller 3 by the pressure plate 4. Here, the pickup roller 3 and the sheet supply roller 2 are driven to rotate counterclockwise by the sheet supply instruction, and the sheet 6 is separated by the friction member 1 and is transferred to the transfer roller pair 5. After the paper 6 reaches the transport roller, the drive of the pickup roller 3 and the paper feed roller 2 is stopped, and the paper 6 is pulled out while being sandwiched between the friction member 1 and the paper feed roller 2. 5 transported.

[0006] As shown in FIG. 6, the corner of the friction member 1 is pressed against the paper feed roller 2 on the side of the conveying roller pair 5 from the uppermost point D of the paper feed roller 2. That is, the feed roller 2
And a tangent line A-C extending toward the transport roller pair 5 at the contact A of the friction member 1 and a straight line AB connecting the nip B of the transport roller pair 5 with the contact A as a starting point,
The friction member 1 is pressed against the sheet feed roller 2 so that the angle guide plate θ has a clockwise direction in the drawing with respect to the tangent line AC. With this configuration, the paper 6 stopped by the friction member 1 to be fed in the next paper feeding is reliably fed by the feeding roller 2.

As described above, when the sheet 6 is pulled and conveyed by the pair of conveying rollers 5, the sheet 6 is moved between the uppermost point D of the sheet feed roller 2 and the nip B of the pair of conveying rollers 5 by the load for extracting the sheet 6. In order to pass on the connecting straight line DB, the frictional member 1 receives a force to be lifted by the sheet 6 to a straight line DB away from the sheet feeding roller 2.

As a result, as shown by the chain line in FIG. 6, the friction member 1 is shifted to a position different from the normal position, deteriorating the separation performance, and causing a problem that double feeding may occur. Further, since the friction member 1 is rubbed against the paper 6 while floating from the paper feed roller 2, there is a problem that noise due to sliding of the paper 6 is likely to be generated.

[0007] In order to solve such a problem, conventionally, FIG.
As shown in (1), the traveling direction of the paper 6 from the paper feed roller 2 is changed obliquely downward, and the transport roller pair 5 is arranged so that the angle θ becomes zero or minus.

[0008]

However, in the above-described conventional paper feeder, the paper feed path cannot be provided linearly, and the size and design flexibility of the apparatus are greatly limited. Was.

The present invention solves the above-mentioned conventional problems, and does not deteriorate the separation performance or generate noise even when the paper is conveyed by the conveying roller pair so as to be pulled out by the friction member and the paper feed roller. It is another object of the present invention to provide a paper feeder that can linearly provide a paper feed path.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a paper feed rotating body for feeding the lowermost or uppermost paper of stacked paper, and a corner portion of the paper feed rotating body. A friction member that is pressed against and prevents double feeding of the sheet, and a pair of conveying rollers provided on the downstream side in the sheet conveying direction of the sheet feeding rotator, and the sheet fed by the pair of conveying rollers is pinched. When done
In a sheet feeding and conveying apparatus for stopping the driving of the sheet feeding rotator and conveying the sheet by the conveying force of the conveying roller pair, the friction member is substantially in a tangential direction at a contact point of the sheet feeding rotator, or the feeding is performed from the contact point. A guide member for guiding the sheet in a direction closer to the center of the paper rotating body is provided between the paper feeding rotating body and the transport roller pair.

Furthermore, in order to achieve the above object, the present invention is characterized in that the guide member is a rotatable roller.

Further, in order to achieve the above object, according to the present invention, the width of the guide member is formed to be longer than the width of the paper rotating body, and the width of the guide member relative to the center in the width direction of the paper rotating body. It is characterized by being arranged symmetrically.

Further, in order to achieve the above object, the present invention is characterized in that the widthwise end of the guide member is chamfered.

[0014]

According to the above arrangement, the guide member for guiding the paper in a direction substantially tangential to the contact point of the friction member with respect to the feed rotary member or in a direction closer to the center of the feed rotary member from the contact point is provided.
Since the paper is provided between the paper feed rotary member and the transport roller pair, even if the paper is pulled out from the friction member and the paper feed rotary member by the transport roller pair, the paper is transported in a direction in which the friction member is not lifted by the guide member. Therefore, it is possible to prevent the separation performance from deteriorating and the occurrence of abnormal noise.

[0015]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a sheet feeding and conveying device according to the present invention, and corresponds to FIG. 7 described above, and the same members are denoted by the same reference numerals.

In FIG. 1, a guide member 7 is provided on an upper guide plate 8 between the paper feed roller 2 and the conveying roller pair 5. The lower guide plate 9 is arranged at a position lowered in accordance with the guide member 7. The lowermost end of the guide surface of the guide member 7 is slightly lower by a distance than the position of the guide member 7 at a tangent line AC extending toward the conveying roller pair 5 at the contact point A between the feed roller 2 and the friction member 1. It is formed so that it becomes. As a result, the guide member 7 guides the paper 6 in a direction approaching the center of the paper feed roller 2 from the contact point A between the paper feed roller 2 and the friction member 1. That is, the guide member 7 guides the paper 6 obliquely downward substantially in the tangential line AC direction.

When the leading end of the sheet 6 to be fed passes through the feed roller 2 and the friction member 1, the lowermost end of the guide surface of the guide member 7 is in friction with the feed roller 2. Since the contact point A of the member 1 is formed to be slightly lower than a tangent line AC extending toward the transport roller pair 5, the member 1 is guided obliquely downward by the guide member 7. When the sheet 6 is guided by the lower guide plate 9 and the guide member 7 as shown by a chain line in FIG.
Led to the nip. When the sheet 6 is nipped by the pair of conveying rollers 5, the driving of the sheet feeding roller 2 is stopped, and the pair of conveying rollers 5 is stopped.
It is conveyed with the conveyance force of. At this time, since the paper 6 is conveyed while sliding on the lowermost end of the guide member 7, the paper 6 is pulled out substantially in the direction of the tangent line AC between the paper feed roller 2 and the friction member 1. Accordingly, no lifting force is applied to the friction member 1, and noise is prevented from being generated.

FIG. 2 shows another embodiment of the present invention, in which the guide member 7 is constituted by a guide roller 7 rotatable around an axis perpendicular to the sheet conveying direction. Guide roller 7
The lowermost end of the guide surface of the paper feed roller 2 and the friction member 1
Tangent line AC extending toward the conveying roller pair 5 at the contact point A of FIG.
Is slightly lower than the position of the guide member 7 by a.

According to this structure, the same effect as in the above embodiment can be obtained, and when the sheet 6 is pulled by the pair of conveying rollers 5 and conveyed while sliding on the guide roller 7, the guide roller 7 rotates. Thus, the load on the paper transport is reduced.

FIG. 3 shows another embodiment of the present invention. The guide member 7 has a width 2 length longer than the width of the feed roller 2.
The sheet feed roller 2 is formed to be longer by the length b and arranged symmetrically with respect to the center in the width direction of the sheet feed roller 2. That is, the guide member 7 is formed to be longer than each end of the sheet feed roller 2 by the length b.

With this configuration, the paper 6 is transported by the transport roller pair 5
When the sheet 6 is pulled, the guide member 7 receives the sheet with a larger area than the sheet feed roller 2, and thus the force that the sheet 6 receives from the guide member 7 is dispersed. Thereby, the damage when the paper 6 is handled by the guide member 7 is reduced, and the paper 6
Wrinkles and the like can be prevented.

Further, in the present invention, as shown in FIG. 4, the end of the guide member 7 in the width direction is chamfered so as to form a taper of angle ψ, and the corner is rounded.

With this configuration, the paper 6 is transported by the transport roller pair 5
When the paper 6 is pulled, the step between the portion on the guide member 7 and the portion coming off the guide member 7 can be reduced, and the damage due to the step when the sheet 6 is handled by the guide member 7 is reduced, and the wrinkles of the sheet 6 are reduced. Etc. can be prevented.

It should be noted that the present invention can be applied to a sheet feeding / conveying apparatus which does not use a pickup roller.

[0025]

According to the first aspect of the present invention, the guide member guides the paper in a direction substantially tangential to the contact point of the rotating member of the sheet feeding rotary member or in a direction closer to the center of the sheet rotating member from the contact point. Is provided between the paper feed rotary member and the transport roller pair, so that even when the paper is pulled out from the friction member and the paper feed rotary member by the transport roller pair and transported, the guide member does not allow the friction member to float. Since the sheet is transported, it is possible to prevent the separation performance from being lowered and the occurrence of abnormal noise.

According to the configuration of the second aspect, the same effect as described above can be obtained, and the load on the paper transport when the paper is pulled by the transport roller pair and slidably contacted with the guide rotating body and transported can be reduced. .

According to the third aspect of the present invention, when the sheet is pulled by the transport roller pair, the guide member can receive the sheet in a larger area than the sheet feeding rotary member, so that the force that the sheet receives from the guide member is dispersed. In addition, since damage when the paper is handled by the guide member is reduced, it is possible to prevent wrinkles and the like from occurring on the paper.

According to the fourth aspect of the present invention, when the sheet is pulled by the pair of conveying rollers, the step between the portion on the guide member and the portion coming off the guide member can be reduced.
Damage when the sheet is handled by the guide member is reduced, and it is possible to prevent wrinkles and the like from occurring on the sheet.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a sheet feeding and conveying device according to the present invention.

FIG. 2 is a schematic configuration diagram showing another embodiment of the present invention.

FIG. 3 is a configuration layout diagram showing still another embodiment of the present invention.

FIG. 4 is an explanatory view showing a modification of the guide member of FIG. 3;

FIG. 5 is an overall schematic configuration diagram of a conventional sheet feeding and conveying device.

FIG. 6 is a schematic configuration diagram of a conventional sheet feeder.

FIG. 7 is a schematic configuration diagram of a conventionally-conveyed sheet feeding device.

[Explanation of symbols]

 2,12 paper feed roller 5,15 transport roller pair 6 paper 7,17 guide member

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-57-209139 (JP, A) JP-A-2-178136 (JP, A) Actually open 1987-178143 (JP, U) Actually open 1987 59639 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B65H 3/52 310 B65H 5/06 B65H 5/38 G03G 15/00 510

Claims (4)

(57) [Claims] A feeder for feeding the lowermost or uppermost sheet of the stacked paper; a friction member for pressing the corner of the feeder to prevent double feed of the paper; A conveying roller pair provided on the downstream side in the sheet conveying direction of the sheet feeding rotator, and when the sheet fed by the conveying roller pair is clamped, the driving of the sheet feeding rotator is stopped, In a sheet feeding and conveying apparatus for conveying a sheet by a conveying force of a pair of conveying rollers, a substantially tangential direction of a contact point of the frictional member at the sheet feeding rotating body or a direction from the contact to a side closer to the center of the sheet feeding rotating body. And a guide member for guiding the sheet is provided between the sheet feeding rotating body and the pair of conveying rollers. 2. The sheet feeding and conveying device according to claim 1, wherein the guide member is a rotatable roller. 3. The paper feeding and conveying device according to claim 1, wherein the width of the guide member is longer than the width of the paper rotating body, and the width of the guide member is set at the center in the width direction of the paper rotating body. A sheet feeding and transporting device characterized by being arranged symmetrically to the left and right. 4. The paper feeding and conveying device according to claim 3, wherein the widthwise end of the guide member is chamfered.