JPH09278247A - Paper discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper discharge device by which a paper sheet can be surely discharged to a paper discharge stacker. SOLUTION: A sponge roller with the same diameter as a discharge roller 3A is installed adjacently to a collar part 3b of the discharge roller 3A integrally rotationally, and multiple small needle type projections 23 arranged on the sponge roller outer circumferential face are protruded to the outside beyond the outer circumference of the collar part 3b. Even if the rear end of a paper sheet fed by means of the discharge roller 3A climbs on the collar part 3b of the discharge roller 3A, the needle type projections 23 hooks the rear end so as to push it, so that the paper sheet 1 can be surely discharge to a discharge paper stacker 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper discharge device for discharging paper to a paper discharge stacker in a facsimile machine, a copying machine or the like.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 5 and 6, an apparatus of this type has a stacker 2 for stacking sheets 1 such as recording sheets.
Has a discharge roller 3 and a discharge roller shaft 4 that holds the discharge roller 3, and a pinch roller 5 that presses the paper 1 against the discharge roller 3 and a pinch roller shaft 6 that holds the discharge roller 3. 3 and the pinch roller 5 sandwiched the sheet, and the sheet was discharged to the sheet stacker 2. here,
A plurality of discharge rollers 3 are attached to the discharge roller shaft 4 at a distance from each other, and each discharge roller 3 has a collar portion 3 having a diameter slightly larger than that of the central cylindrical portion 3a at both ends.
b is formed. As can be seen from FIG. 6, the collar portion 3b is provided to cause the sheet 1 to bend when the sheet 1 is sandwiched between the discharge roller 3 and the pinch roller 5, and forms the sheet 1 on the curved portion. As a result, the rigidity of the paper 1 is strengthened, and the paper 1 can be satisfactorily discharged to the paper discharge stacker 2.

[0003]

However, in such a conventional configuration, it is preferable that the paper stacker 2 stack the sheets 1 in a substantially horizontal state, but as shown in the figure, the sheets 1 are set up diagonally. There was a problem when stacking in a stuck state. That is, as shown in FIG. 5B, when the sheet 1 is discharged by sandwiching it between the discharge roller 3 and the pinch roller 5, and the trailing end of the sheet 1 comes out of the nipping / conveying portion P between the discharge roller 3 and the pinch roller 5, the sheet 1 is discharged. 1 may be balanced by its own weight, that is, in the state where the trailing edge of the sheet 1 is in the vicinity of the nipping / conveying portion P of the discharging roller 3, the discharging roller 3
Despite the rotation of the paper, the paper 1 slipped on the trailing edge of the paper 1 and the paper 1 could not be ejected to the paper ejection stacker 2. If the sheet 1 remains on the discharge roller 3 as described above, when the succeeding sheet 1 is fed, the sheet 1 is pushed out of the discharge stacker 2, or the sheet is jammed. Cause problems.

The present invention has been made in view of the above-mentioned problems, and is a sheet ejection device capable of reliably ejecting a sheet to a sheet ejection stacker that stacks sheets in an upright state. The purpose is to provide.

[0005]

In order to solve the above-mentioned problems, the present invention has a sponge roller attached to the end of the discharge roller. By providing this sponge roller, even if the trailing edge of the ejected paper rides on the outer circumference of the ejection roller, the innumerable needle-shaped protrusions existing on the outer periphery of the sponge roller cause the trailing edge of the paper to move. It can be hooked and pushed, and can be reliably ejected to the output stacker.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a paper discharge device provided with a discharge roller arranged adjacent to a discharge stacker for stacking paper and a pinch roller for pressing the paper against the discharge roller. A sponge roller is provided so as to rotate integrally with the end of the discharge roller.
The sponge roller is made by punching out a sponge material. At that time, innumerable needle-shaped projections are formed on the outer surface, and thus the innumerable needle-shaped projections are projected on the outer peripheral surface of the sponge roller. If this sponge roller is provided at the end of the discharge roller, even if the trailing edge of the discharged paper rides on the outer circumference of the discharge roller, the innumerable needle-shaped protrusions existing on the outer circumference of the sponge roller. The paper can be caught in the rear end of the paper and push the paper, and the paper can be reliably discharged to the paper discharge stacker.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments shown in the drawings will be described below. In addition,
The same parts as those of the conventional example shown in FIGS. 5 and 6 are designated by the same reference numerals. FIG. 4 is a schematic cross-sectional view of a part of a facsimile apparatus equipped with a paper discharge device according to an embodiment of the present invention. 11 is a paper feed cassette storing a large number of papers (recording papers) 1, and 12 is a paper feed cassette 11. Paper feed roller for feeding out the papers 1 one by one, 13 is a registration roller for sending out the supplied papers 1 at the timing of the operation of the downstream recording unit, and 14 is a process cartridge including a photosensitive drum 15, A charging device, a developing device, a cleaner and the like (not shown) are provided inside. Reference numeral 16 is a laser scanning unit that scans the surface of the photosensitive drum 15 with a laser beam to form an electrostatic latent image according to the received information, and 17 is a transfer roller that transfers the toner image formed on the photosensitive drum 15 onto the sheet 1. , 18 are fixing devices for heating and fixing the toner image on the sheet 1. A sheet discharging device 20 according to the embodiment of the present invention is arranged downstream of the fixing device 18 so that the sheet 1 is discharged to the sheet discharging stacker 2 arranged in the vicinity thereof.

As shown in FIGS. 1 to 3, the sheet discharging device 20 includes a discharging roller shaft 4, discharging rollers 3 and 3A held by the discharging roller shaft 4, a pinch roller 5 for pressing the sheet 1 against the discharging rollers 3 and 3A, and the pinch roller 5. Has a pinch roller shaft 6 for holding. Here, the discharge roller 3 arranged at the center of the discharge roller shaft 4 has the same structure as the conventional one shown in FIGS. 5 and 6, but the discharge rollers 3A arranged on both sides thereof are
The flange 3b is provided only at the inner end of the cylindrical portion 3a,
No flange is formed on the outer edge. A sponge roller 22 is fixed to the inner end of the discharge roller 3A by adhesion or the like, and is provided so as to rotate integrally with the discharge roller 3A. Here, the outer diameter of the sponge roller 22 is set to be substantially equal to or slightly larger than the maximum outer diameter of the collar portion 3b of the discharge roller 3A. The sponge roller 22 is formed by punching out a sponge material. At this time, the three-dimensional network structure of the sponge material is cut, so that innumerable needle-shaped protrusions remain on the outer surface. Therefore, innumerable needle-shaped protrusions are projected on the outer peripheral surface of the sponge roller 22, and when the sponge roller 22 is attached to the end surface of the discharge roller 3A, as shown exaggeratedly in FIG. The needle-like protrusion 23
Is projecting outward from the outer periphery of the flange portion 3b of the discharge roller 3A. In order to form many such needle-like protrusions, it is preferable to form the sponge roller 22 using a sponge material having a high expansion ratio.

Next, the operation of the paper discharge device 20 having the above structure will be described. Also in this paper discharge device 20, FIG.
(A) As shown in FIG. 2, the discharge rollers 3 and 3A and the pinch roller 5 rotate with the paper 1 sandwiched therebetween, and discharge the paper 1 to the paper discharge stacker 2. At this time, the collar portion 3b assists in bending the sheet 1 so that the sheet 1 can be bent and is properly sent to the sheet stacker 2. When the trailing edge of the sheet 1 is fed out of the nipping / conveying section P between the discharge rollers 3 and 3A and the pinch roller 5, the sheet 1 may be fed by its own weight as shown in FIG. The rear end may be in a state of riding on the collar portion 3b of the discharge roller 3A. However, the needle-like protrusions 23 on the outer peripheral surface of the sponge roller 22 are located outside the outer periphery of the collar portion 3b of the discharge roller 3A.
, The needle-like protrusions 23 are caught on the rear end of the sheet 1 as the sponge roller 22 rotates, and push the sheet 1 to eject it toward the sheet ejection stacker 2. Thus, the sheet does not remain on the discharge rollers 3 and 3A in a state of being placed thereon. Further, since the sponge roller 22 is provided on each of the two discharge rollers 3A and 3A which are arranged with a gap, the two sponge rollers 22 are pushed at two positions apart from each other, so that the paper 1 can be surely discharged. At this time, the needle-like protrusions 23 formed on the outer peripheral surface of the sponge roller 22.
Are extremely small and innumerable, the left and right sponge rollers 22 and 22 can push the rear end of the sheet 1 at the same time, and the trouble that the sheet 1 is pushed out obliquely does not occur.

In this embodiment, no flange is formed outside the discharge roller 3A. Therefore, the portion of the sheet 1 that passes through this position is not curved. As a result of confirmation by the present inventors, when a curve is formed near the side edge of the paper 1,
It often remains as a curl, and particularly when the fixing device 18 is located immediately upstream and heats the sheet 1 as in this embodiment, it often remains as a curl. In contrast,
In the present embodiment, the flange portion on the outside of the discharge roller 3A is eliminated and the side edge portion of the sheet 1 passing therethrough is not curved, so that there is an advantage that curling can be prevented. Further, as a result of confirmation by the present inventors, there is no particular hindrance to the ejection of the sheet 1 even if this portion is not curved.

In the above embodiment, the sponge roller 22 is used.
Are provided on the flange portions 3b of the discharge rollers 3A and 3A arranged on both sides, but instead of this, they may be attached to the flange portions 3b on both sides of the central discharge roller 3. However, when the sponge roller 22 is attached to the outer discharge rollers 3A and 3A as in the illustrated embodiment, the distance between the two sponge rollers 22 and 22 can be increased, so that the distance between the positions where the rear end of the sheet 1 is pressed can be increased. There is an advantage that the sheet 1 can be widened and the sheet 1 can be discharged stably. Further, the sponge roller 22 may be attached to all the discharge rollers 3 and 3A. Further, in the above embodiment, the discharge rollers 3 and 3 having the collar portion 3b are provided.
Although A is used, it is also possible to use a simple cylindrical discharge roller without a collar portion. In that case, one or both ends of the discharge roller are substantially the same as or slightly larger than the discharge roller. A sponge roller having a diameter may be attached.

[0012]

As is apparent from the above description, according to the present invention, the sponge roller is provided at the end portion of the discharge roller, so that even if the trailing end of the discharged paper rides on the outer circumference of the discharge roller, the sponge roller is sponged. Innumerable needle-shaped protrusions on the outer circumference of the roller hook the rear end of the paper to push it, and it can be reliably ejected to the paper eject stacker. Since it can be manufactured and simply fixed to the discharge roller by adhesion or the like, the structure is simple and the manufacturing cost is low.

[Brief description of drawings]

FIG. 1A is a schematic sectional view showing a state where a sheet is being ejected by a sheet ejection device according to an embodiment of the present invention, and FIG. 1B is a schematic sectional view showing a state where a trailing edge of a sheet is on an ejection roller.

FIG. 2 is a schematic front view of the sheet ejection device of the embodiment shown in FIG.

3 is a schematic perspective view showing a discharge roller and a discharge roller shaft used in the paper discharge device shown in FIG.

FIG. 4 is a schematic cross-sectional view of a facsimile device equipped with the paper ejection device of the embodiment shown in FIG.

5A is a schematic cross-sectional view showing a state in which a sheet is discharged by a conventional sheet discharge device, and FIG. 5B is a schematic cross-sectional view showing a state in which the trailing edge of the sheet is placed on a discharge roller.

FIG. 6 is a schematic front view of a conventional paper ejection device.

[Explanation of symbols]

 1 Paper 2 Paper Ejection Stacker 3, 3A Ejection Roller 3a Cylindrical Part 3b Collar Part 4 Ejection Roller Axis 5 Pinch Roller 6 Pinch Roller Axis 11 Paper Feed Cassette 14 Process Cartridge 15 Photosensitive Drum 16 Laser Scan Unit 18 Fixer 20 Paper Ejection Device 22 Sponge roller 23 Needles

Claims (1)

[Claims] 1. A discharge roller disposed adjacent to a discharge stacker for accumulating paper, a pinch roller for pressing the paper against the discharge roller, and an end portion of the discharge roller provided so as to rotate integrally. And a sponge roller having a large number of needle-shaped projections protruding outward from the outer circumference of the discharge roller.