JP2501210Y2 - Stacked recording paper sorting mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an improvement of a sheet feeding device used in an image forming apparatus, and more particularly, to a multi-feeding method that tends to occur when stacked recording sheets are in close contact with each other. The present invention relates to a stacking recording paper separation mechanism capable of preventing the occurrence.

(Prior Art) An image forming apparatus such as a copying machine, a printer, or a facsimile machine uses a toner image on a recording sheet fed to an image forming section including a photoconductor or a printing section including a print head. The desired image is obtained by transferring or printing the dot pattern.

For continuous image forming work, a large number of recording papers (cut sheets) are stacked on a recording paper storage unit such as a paper feeding cassette, and the uppermost or lowermost surface of the recording paper bundle is pressed against the sheet. It is convenient to separate and take out the sheets one by one with a paper roller and feed them to an image forming unit or the like, and this method is generally practiced.

By the way, the stacked recording papers have strong adhesion due to paper quality, paper thickness, self-weight, mutual frictional resistance, static electricity, etc., and when picked up by a paper feed roller, two or more sheets are overlapped and fed. Double feed may occur. In order to prevent the occurrence of double feed, the friction pad is brought into contact with the paper feed roller to separate the recording paper in the double feed state that passes between the two, and to the outer peripheral surface of the paper feed roller. A reverse roller system in which a reverse roller that rotates in the opposite direction is nipped is also effective, but even when these double feed prevention mechanisms are used, double feed occurs if the adhesion between recording sheets is strong. Sometimes.

(Purpose of the Invention) The present invention has been made in view of the above, and it is possible to prevent incomplete separation and double feeding at the time of paper feeding caused by strong adhesion between stacked recording papers. It is an object of the present invention to provide a stacking recording paper sorting mechanism capable of performing the above.

(Constitution of the Invention) In order to achieve the above-mentioned object, the present invention is a stacking recording paper separating mechanism for separating stacked recording papers and feeding the recording papers one by one. A paper feed roller which is provided so as to contact the paper and which feeds out the uppermost recording paper, a first rotation driving means which rotationally drives the paper feed roller in the feeding direction, and a feeding direction of the stacked recording papers. Arranged so that the bundle of recording paper in the first half is judged,
The leading end side abuts on the end of the recording paper on the upper side of the recording paper bundle, pushes the end upward and separates the paper, and the base end side shifts in a direction perpendicular to the axis of rotation with respect to the axis of rotation. A separating member that is supported in a cantilever shape and that retracts from the feeding path when feeding the recording paper, a second rotation driving unit that rotationally drives the rotation shaft, and the first and second rotation driving units are different from each other. Control means driven at timing,
The separation member is provided with an elastic stopper that is locked when the rotation shaft is not rotating, and elastically deforms when driven by the second rotation driving means to allow rotation of the separation member. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing a schematic structure of a first embodiment of the present invention. A paper feed roller shaft 11 is rotatably supported by a side wall, a support or a bearing member 10 and is attached to the tip of the shaft 11. The paper feed roller (feed roller) 12 fixed is the paper feed cassette 13
It is in contact with the upper surface of the upper recording paper P. A transmission gear or pulley 17 is connected to the other end of the shaft 11 via an electromagnetic clutch 16.
The gear 17 and the like are engaged with a timing belt (or a chain) 19 to receive transmission of a driving force from a motor that drives the belt 19.

A separating member 24, which is rotatably supported by the bearing member 20, is fixed to the tip of a separating member shaft 21 made of rubber, resin, or the like having a shape such as a circular shape, an oval shape, or a streamline shape. The other end of the shaft 21 is connected to the transmission gear 26 via the electromagnetic clutch 25.
The transmission gear 26 is connected to the belt 19 via the intermediate gear 27. Therefore, the separating member shaft 21 rotates in the opposite direction to the paper feeding roller shaft 11.

At least the tip portion (contact portion with the side surface of the recording paper) of the separating member 24 is made of rubber or the like having a high friction coefficient. The separating member is arranged at a position that does not obstruct the paper feed roller or the conveyance path of the recording paper taken out by the paper feeding roller, and the elastic stopper 30 projects into the rotation trajectory of the separating member 24. ing.

The elastic stopper 30 is made by processing an elastic material such as rubber into a rod shape, and is provided so as to project from the base 31 on the apparatus main body side, and locks the separating member 24 when it strikes, while the separating member 24 When is pressed down, it is elastically deformed to allow passage of the separating member (see FIG. 5).

 Reference numeral 28 is a friction pad.

The electromagnetic clutches 16 and 25 are ON / OFF controlled by a control unit such as a microcomputer (not shown).

2 (a) to (d) are operation explanatory views of the separating member, and the separating member is shown at the start of the separating operation shown in (a).
The leading end of 24 presses against the position of about 10 sheets from the upper surface of the recording sheet bundle, and pushes it up as it rotates in the direction of the arrow (upward). When the separating member 24 is further rotated upward as shown in (b), the lower part of the recording paper is pushed down by the slip between the leading end of the separating member and the leading edge of each recording paper, and then downwards. When the separating member finishes separating the recording paper as shown in (c), it further rotates in the same direction and contacts the stopper 30 to stop. This stop timing is realized by the control unit controlling the electromagnetic clutch 25. That is, the clutch is turned off when the separating member reaches the position immediately before the stopper, and then the stopper member is locked by the dead weight of the separating member.

It is preferable that the separating member 24 is controlled so as to operate every time the paper is passed or every several times, and the number of rotations during one operation is once or twice or more.

In this embodiment, the leading end side of the recording paper in the conveyance direction is judged, but the lateral side of the recording paper bundle may be judged.

If the shaft 21 is too long and there is a risk of swaying or eccentricity of the shaft, support struts for bearings may be provided at several places other than those shown in the drawing.

Also, the paper feed cassette is provided with a corner separator, which presses the upper surface of the recording paper, but since the separating member of the present invention only separates about 10 sheets from the top of the recording paper stack, The influence of the load from the separator is not considered.

The arrangement position of the separating member 24 shown in FIGS. 2 (a) to (d) is as follows during the separating operation ((a) and (b) in the drawing).
Although it interferes with the paper feed roller or the conveyance path of the recording paper taken out, it is moved to the retracted position (d) during paper feeding,
There is no obstacle.

FIG. 3 is an explanatory diagram of the drive timing of the sheet feeding roller and the separating member, and it is preferable to provide a gap between the feeding operation by the sheet feeding roller and the separating operation by the separating member. As shown in the figure, the separating member is operated only once immediately before the driving of the paper feed roller is started.

Alternatively, as shown in FIG. 4, the separating member may be continuously rotated a plurality of times immediately before the start of the operation of the paper feed roller.

Next, FIGS. 6 (a) and 6 (b) are a plan view and a front view of a second embodiment of the present invention, in which each shaft 11, 21 pivotally supported by the side plate 36 is provided with no clutch, A characteristic is that each of them is directly driven by the pulse motors 40 and 41.

Also in this embodiment, when there is a risk that the separating member 24 may project into the conveyance path of the recording paper, it is necessary to provide the stopper 30 as in the case of the above embodiment, but normally the judgment is performed by controlling the pulse motor. Since the member can be stopped outside the transport path and put in the standby state, the stopper can be omitted.

FIGS. 7 (a) and 7 (b) are modified examples of the embodiment shown in FIG. 6, and are characterized in that a separating member 24 is provided at a lateral position of the recording paper stack and is driven by a drive motor 50. is there.

Of course, the separating member may be provided at the side position and at the same time as the separating member may be provided at the front position of the recording paper.

FIG. 8 shows a third embodiment of the present invention, which is characterized in that a plurality of separating members 24 are fixedly attached to a single shaft 21 at predetermined intervals. Since the distribution is not localized, the judgment effect can be greatly improved.

FIG. 9 is a fourth embodiment of the present invention, in which an air jetting nozzle 60 is arranged in the vicinity of the separating member, and is pushed up by the separating member to increase the distance between recording sheets. In addition, the blowing effect is greatly improved by blowing air.

The nozzle may be integrated with the separating member itself.

FIG. 10 shows a modified example of the separating member, in which a blade-shaped fan is provided on the separating member itself so that the separating effect is increased by the flow of air generated when the separating member rotates.

(Effect of the Invention) As described above, according to the present invention, the separating member is locked by the elastic stopper when rotation of the separating member is stopped, and elastically deformed when the separating member is driven to allow rotation of the separating member. Therefore, it is possible to reliably separate the sheets by the separating member only when necessary, and the recording sheets located above the recording sheets stacked in the paper feeder are separated and the mutual adhesion of the recording sheets is eliminated. The effect of preventing double feeding caused by the close contact of the recording papers can be enhanced, and the uppermost recording papers stacked can be reliably fed.

[Brief description of drawings]

FIG. 1 is a perspective view showing a schematic structure of a first embodiment of the present invention, FIGS. 2 (a) to 2 (d) are explanatory views of the operation of a separating member, and FIGS. FIG. 5 is an explanatory view showing the operation timing of the paper roller, FIG. 5 is an operation explanatory view of the stopper, and FIGS. 6 (a) and 6 (b) are a plan view and a front view showing the configuration of the second embodiment of the present invention. 7 Figures (a) and (b)
Is an explanatory view of a modified example of the embodiment of FIG. 6, FIG. 8 is an explanatory view of the configuration of the third embodiment of the present invention, FIG. 9 is an explanatory view of the fourth embodiment of the present invention, and FIG. It is a structure explanatory view of the modification of a separating member. 10 …… Side wall, column or bearing member, 11 …… Paper feed roller shaft, 12
…… Paper feed rollers (feed rollers), 16 …… Clutch, 17
...... Gear, etc. 19 ...... Chain, etc. 24 …… Separating member, 30
...... Elastic stopper

Claims (1)

(57) [Scope of utility model registration request] 1. A stacked recording paper separating mechanism for separating stacked recording papers and sending the recording papers one by one, which is provided so as to come into contact with the uppermost recording papers of the stacked recording papers. Paper feed roller for feeding out the recording paper, first rotation driving means for rotatably driving the paper feed roller in the feeding direction, and the first half of the recording paper bundle in the feeding direction of the stacked recording papers is judged. The front end side contacts the end of the recording paper on the upper side of the stack of recording papers and pushes the end upward to separate the paper, and the base end side intersects the axis with the axis of rotation at right angles. And a separating member that is supported in a cantilever manner in the direction and retracts from the feeding path when the recording paper is fed, a second rotation driving unit that rotationally drives the rotation shaft, and the first and second rotation driving units. Drive at different timings Control means, and an elastic stopper that locks the separating member when the rotation shaft is in a rest state and elastically deforms when driven by the second rotation driving means to permit rotation of the separating member. A sorting mechanism for stacked recording paper, which is characterized in that