JPS58183540A - Stacked sheet separating and transporting apparatus - Google Patents

Abstract

PURPOSE:To assuredly separate stacked sheets to be transported sheet by sheet from the uppermost sheet to the lowermost sheet in an apparatus for separating and transporting sheets stacked on a sheet placing table sheet by sheet by moving the sheet placing table up and down. CONSTITUTION:Projecting portions 3', 3'' of a sheet placing table 3 opposed to a paper feed roller 4 and a reverse roller 5 pierce a shaft 21, and a movable plate 20 is pivotally mounted on a shaft 21, the forward end portion of the movable plate 20 being restricted in the downward movement at a fixed position by a stopper 22. In response to a paper feed start signal, a lever 201 is attracted by an electromagnetic solenoid 24 to move the movable plate 20 clockwise, and with rotation of both rollers 4, 5, a sheet material 2 is transported to register rollers 8, 9. After that, on completion of copying, the electromagnetic solenoid 24 is turned off, so that the movable plate 20 is moved counter-clockwise by restoring force of a spring 23. Subsequently, the sheet placing table 3 is again moved clockwise to transport the uppermost sheet material 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stacked sheet separation and conveyance device for copying machines, printing machines, recording machines, and other machines having a mechanism for separating and conveying stacked sheets one by one (hereinafter referred to as copying machines). be.

Conventionally, in this type of apparatus, in which stacked sheets are separated and conveyed by a pair of rollers, the sheet stacking table is tilted to the pair of rollers so that the sheets stacked on the sheet stacking table can fall naturally to the separation conveyance section. It was placed almost on a tangent.

However, for example, when sheets are stacked as shown in Fig. 1, there is no guarantee that the sheets will be fed out first, and there is also a risk that multiple sheets will get stuck in both rollers and be fed at the same time. In that case, there is a drawback that an abnormal load is generated between both rollers, resulting in damage to the device.

Furthermore, if the sheet loading platform is placed lower than the tangential position of both rollers as shown in Fig. 2, the lower sheet of the stacked sheets will only hit the reversing roller and will not be fed out. Met.

Therefore, an object of the present invention is to provide a new stacked sheet separation and conveyance device that is improved in view of these drawbacks.

□ Another object of the present invention is to provide a stacked sheet separation and conveyance device that can reliably separate and convey stacked sheets from the top to the bottom.

That is, the main structure of the present invention that can achieve the above object is a stacked sheet separation and conveyance device that separates and conveys the sheets stacked on a sheet stacking table one by one, and the sheet loading table is movable up and down. This is a featured stacked sheet separation and conveyance device.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. FIG. 3 is a cross-sectional view of an electrophotographic copying apparatus to which the present invention is applied. In the figure, reference numeral 1 denotes a photosensitive drum rotating in the direction of the arrow. A cleaning means and a cleaning means for removing residual toner after transfer are omitted and not shown.

First, we will discuss the process of transporting sheet materials within the device. One or more sheets of sheet material 2, which are conveyed in synchronization with the image on the photosensitive drum 1, are stacked on a sheet stacking table 3. The stacked sheet materials 2 are sent out by the feed roller 4 rotating in the direction of the arrow, guided by the guide plate 6.7 to the register roller 8.9, and the rotation of the feed roller 4 is stopped. At this time, in order to separate the stacked sheet materials 2 and convey only the upper sheet, the separation roller 5 rotates in the opposite direction to the sheet conveyance direction as shown by the arrow. The sheet material 2 that has reached the register roller 8.9 starts rotating in synchronization with the image on the photosensitive drum 1, and the sheet material 2 is guided by guides 10 and 11 and conveyed to the photosensitive drum 1. At the point where the photosensitive drum 1 and the sheet material 2 come into contact, a corona discharger 12 discharges and applies a potential, so that the image on the drum 1 is transferred to the sheet 2. Furthermore, sheet conveying means 13
The paper is guided to the fixing device 14, 14' and discharged onto the paper discharge tray 15.

The position of the sheet loading table relative to the paper feeding roller 4 and the reversing roller 5 is shown in detail in FIG.

The sheet loading platform 3 is fixed to the device, and its protrusion 3
A shaft 21 passes through the shafts 21 and 3". A movable plate 20 is attached to the shaft 21 so as to be movable about the shaft 21, and the tip of the movable plate 20 is held constant by a stopper 22. The downward movement is restricted at the position (below the nip portion of roller 4.5).
4. The swing movement of the movable plate 20 is performed using the lever 20. The solid line position and the broken line position 2 are moved by swinging by the electromagnetic thread 24.
It is movable to 0'. Normally, the movable plate 20 is pulled by the force of the spring 230, so that it stops when it hits the stopper 22. Load the sheet here on platform 3
Place it on top of the sheet and push it in until the tip of the sheet hits reverse low → -5.

Next, in response to a paper feed start signal, the electromagnetic solenoid 24 is attracted and the movable plate 20 rotates clockwise until the top end of the sheet abuts the 4' portion of the paper feed roller 4. Simultaneously with the paper feed start signal, the paper feed roller 4 and the reversing roller 5 start rotating in the directions of the arrows. At this time, since the uppermost sheet material is in contact with the paper feed roller 4, the sheet material 2 is conveyed to the register roller 8.9. Normally, the friction coefficients on the surfaces of the paper feed roller 4 and reversing roller 50 are in the relationship of paper feed roller>reverse roller 5>sheet material 2, so even if the lower side is reversed, the sheet material 2 is conveyed by the paper feed roller 4, and the sheet material 2 is conveyed until the end. Even if the sheet below the upper sheet moves to the reversing roller 5 while being dragged by the upper sheet, it slips between the sheets, the upper sheet is fed by the paper feed roller 4, and the lower sheet is stopped by the reversing roller 5 and separated. . Sheet material 2
When the paper has been completely fed, the movable plate 20 moves to a tangent line between the paper feed roller 4 and the reversing roller 5 and stops. At the same time as the copying is completely completed, the electromagnetic solenoid 24 is turned off, and the movable plate 20 is moved counterclockwise by the return force of the spring 23 to return to the maximum position.

In this initial state, the sheets are stacked in a state similar to that shown in FIG. They will be sent away.

Although this embodiment shows an example in which only the tip of the sheet stacking table is swingable, the entire sheet stacking table may be swingable.

In addition, in double-sided copying, the single-sided copied sheets are once stacked on the tray, but normally they are stacked as shown in FIG. 1, so they are stacked in the worst condition as described above, and separation and conveyance does not go well. In addition, in the method of sequentially feeding sheets from the lower tier, as the number of sheets stacked increases, a load is applied to the sheet material to be fed from the lower tier, and the sheet material cannot be conveyed smoothly.

The configuration of the present invention can also be used in such cases.

As explained above, according to the configuration of the present invention, the stacked sheets are reliably separated and conveyed one by one starting from the top one. Furthermore, since the leading end of the sheet plate is pushed up, the pushing force increases the conveying force for feeding out, thereby ensuring reliable feeding.

Furthermore, it also has the effect of increasing the number of sheets that can be loaded.

[Brief explanation of the drawing]

1 and 2 are sectional views showing a conventional example, FIG. 3 is a sectional view showing a copying machine to which the present invention can be applied, and FIG. 4 is a sectional view showing an embodiment of the present invention. , 5 is a separation roller, 2
0 is a movable plate, and 22 is a stopper. Applicant Canon Co., Ltd. 299

Claims (3)

[Claims] (1) A stacked sheet separating and conveying device that separates and transports sheets stacked on a sheet stacking table one by one, the stacked sheet separating and conveying device being characterized in that the sheet stacking table is movable up and down. (2) The loaded sheet separating and conveying device according to claim 1, wherein the loaded sheet separating and conveying device is a pair of rollers that rotate so as to send the sheets in directions opposite to each other with respect to the sheet feeding direction. (3) The stacked sheet separating and conveying device according to claim 1, wherein the sheet stacking table moves upward when starting to feed out the sheets.