JPS6042138B2 - Air-feeding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paper feeder that separates sheets stacked on a paper feeder one by one and feeds them to a processing device, specifically, a paper feeder that feeds sheets by suctioning them with air. This relates to paper devices.

2. Description of the Related Art Devices equipped with a paper feeding device that separates stacked sheets one by one include printing machines, copying machines, and facsimile machines.

Compared to printing machines and copying machines, facsimile machines require a particularly reliable separation and feeding of original documents. Moreover, since the above-mentioned documents to be transmitted tend to use sheets of various paper quality, rigidity, etc., conventional paper feeding devices using corner claws are not useful. Therefore, in the field of facsimile, air feeding devices that suck sheets by suction action have attracted attention and have been put into practical use.

One example is shown in FIG. 1, where numeral 1 indicates a vacuum box. The upper end of the vacuum box 1 is open and communicates with an axial fan 2.
The vacuum box 1 is provided with a feeding roller 3 that is connected to a drive mechanism (not shown) and rotates in the direction of the arrow, in a direction perpendicular to the sheet feeding direction.

Further, a vacuum plate 4 is swingably attached to the vacuum box 1 via a support shaft 5 so as to form the bottom of the vacuum box 1 .

The plate 4 is provided with a hole 4a into which the feeding roller 3 fits and which sucks the sheet 6 when the plate 4 is raised as shown by the solid line. When the device is not in operation, the vacuum plate 4 is lowered as shown by a chain line 4AJ, and its tip is brought into contact with the uppermost sheet. The sheets 6 are stacked on a paper feed tray 7 with their leading edges aligned.

Now, when a paper feeding command is issued, the axial fan 2f operates and begins to remove air from the vacuum box 1, and the feeding roller 3 rotates in the direction indicated by the arrow.

The uppermost sheet is attracted to the vacuum plate 4A by air sucked through the hole 4aA of the vacuum plate 4A.
Then, the plate 4 with the hole closed swings and rises as shown by the solid line due to the suction action described above. The sheet 6 attracted to the vacuum plate 4 is sent out in the direction of arrow a by the feeding roller 3 seen through the hole 4a. If we consider the movement of the sheet when it is sucked to the vacuum plate 4, the tip of the sheet 6 is held down by the tip of the plate, so the topmost sheet that should be sucked into the hole 4a If one sheet is in close contact with the next sheet, there is a problem in that multiple sheets are attracted without being easily separated, and an accident occurs in which multiple sheets are fed into the processing device.

This phenomenon of multiple sheet feeding must be avoided, especially in facsimile transmission documents. Furthermore, feeding multiple sheets may cause vapor jams. In order to solve the above-mentioned problems, the present invention provides a sheet holding part that forms a gap between the vacuum plate and the tip of the sheet, so that the sheet can be attracted to the plate from the tip of the sheet. At the same time, an air feeding device is provided to ensure sheet separation by forming a gap between the sheets at the leading end of each sheet, and two holes for sheet suction are provided at the leading end of the sheet holding part. Accordingly, an object of the present invention is to provide an air paper feeding device that concentrates suction force on the sheet at the leading edge of the sheet, thereby enabling more reliable separation of sheets. The present invention will be explained below with reference to the illustrated embodiments! Ru.

Incidentally, members that perform the same functions as those of the conventional device shown in FIG. 1 are designated by the same reference numerals, and individual explanations will be omitted. Second
In the figure, a vacuum plate 150, which is swingably attached to the vacuum box 1 on a support shaft 5, has a hole 12 through which the feeding roller 3 looks through and sucks the sheet 11, as shown in FIG. A hole 13 for suctioning the tip and a hole 14 for suctioning both corners of the tip of the sheet are provided.

Further, the vacuum plate 10 is provided with a sheet pressing portion 15 with the tip portion 10a bent in a direction to move away from the sheet 11 at a position slightly rearward from the center of the hole 412. The vacuum plate 10 is
In the inactive position of the device, as shown in Figure 2,
The sheet pressing portion 15 is brought into contact with the sheet 11 near its leading end. Therefore, as shown in FIG. 4, the sheet 11 whose leading end is held down by the sheet presser 15 is lifted upward, and there is a slight gap between the topmost sheet 11a and the next sheet 11b. However, a gap A is created, and the sheets are already separated from each other at the leading end. Now, when a paper feeding command is issued, a vacuum mechanism (not shown) is activated and begins to remove the air within the vacuum box 1.

Then, the leading edge of the uppermost sheet 11a with a gap created in advance between it and the next sheet 11b is aligned with the chain line 11a.
Holes 12, 13 of vacuum plate 10 as shown in A
, 14. The corners of the tip are also attracted. Then, each hole of the vacuum plate 10 is connected to the seat 1.
When the plate 1a is closed, the plate 10 that has attracted the sheet 11a swings and rises as shown in FIG.

As the plate 10 rises, the feed roller 3, which is rotating in the direction indicated by the arrow, peeks through the hole 12, contacts the sheet being sucked, and sends it out in the direction indicated by friction by friction. As described above, according to the air feeding device of the present invention provided with the sheet presser, when the sheet presser presses the sheet, a gap is created between the leading edges of the sheets, and the sheets are no longer in close contact with each other. Since the leading end of the sheet is first attracted to the vacuum plate, reliable separation and feeding is performed without having to feed multiple sheets.

Next, a vacuum plate having a hole for sucking a sheet closer to the leading edge of the sheet than the sheet pressing portion will be described with reference to FIG. In the figure, the vacuum plate 100 is provided with a hole 120 for sheet suction, which includes a hole through which the feeding roller 30 looks, and holes for suctioning the leading edge and corner of the sheet, closer to the leading edge of the sheet than the sheet holding part 150. ing. In this case, the feed roller 30 is formed as small and thin as possible to the extent that it can perform a sufficient sheet feeding action, and at the same time, the hole through which the roller 30 passes is also made small. Further, the hole for suctioning the leading edge of the sheet and the corner of the sheet and the hole through which the roller 30 looks may be one hole formed in a T-shape as shown in FIG. In the vacuum plate in which holes for sheet suction are provided at the tip of the sheet presser, holes for the roller and holes for suction at the tip and both corners of the sheet are formed separately as shown in Fig. 5. Of course it's a good thing. As mentioned above,
According to a vacuum plate in which a hole for sheet suction is provided at the tip of the sheet holding section, in addition to the effect of the sheet holding section, the sheet sucked by the plate is first separated from the tip and then sucked, so that the vacuum plate is more Reliable separation and feeding can be performed. The effect of suctioning a sheet from its leading edge is that when lifting the top sheet of a stack of sheets by suction, it is better to suction the edges, including the corners, first than to suction the center of the sheet. This is easy to understand because air flows between the sheets that are in close contact with each other, making it easier to peel them off and requiring only a small suction force. Further, as the air bleed means, an axial fan may be disposed above the vacuum box, but the box may be connected to the air bleed means installed elsewhere using a vibrator, a shutter, or the like.

Furthermore, in the illustrated embodiment, the vacuum plate is swingably attached to the vacuum box;
It may be moved vertically in parallel using a link mechanism or the like. When the vacuum plate is moved in parallel, there is no change in the amount of gap between the same plate and the uppermost sheet depending on the amount of sheets, which has the effect of allowing more stable paper separation and feeding.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view showing a conventional example of the present invention, Fig. 2 is a side sectional view showing an embodiment of the present invention, Fig. 3 is a view of the same operation, and Fig. 4 is a detailed explanation of the present invention. 5 is a plan view showing only the essential parts of the vacuum plate, FIG. 6 is a side sectional view showing another embodiment of the present invention, and FIG. 7 is a portion showing another embodiment of the vacuum plate. FIG. 1...Vacuum box, 3゜゜゜feed roller, 1
0... Vacuum plate, 11... Woot, 12...
... Hole, 13, 14... Woot suction hole, 15... Sheet holding part.

Claims (1)

[Scope of Claims] 1. In an air feeding device that has a vertically movable vacuum plate that sucks sheets and has a hole through which a feeding roller can be seen, and a feeding roller that sends out the sucked sheets, before the suction starts, An air feeding device characterized in that a vacuum plate is provided with a sheet pressing portion that forms a space between a leading edge of a sheet and a vacuum plate. 2. In an air feeding device that has a vertically movable vacuum plate that sucks sheets and has a hole through which the feeding roller can be seen, and a feeding roller that sends out the sucked sheet, the sheet and vacuum plate are separated before the start of suction. An air feeding device characterized in that a sheet suction hole is formed in the direction of the leading edge of the sheet, rather than the sheet holding part for forming a gap between the sheets.