JPH038665Y2 - - Google Patents

Description

[Detailed description of the invention] -Field of industrial application- This invention relates to a device that automatically supplies sheet-like paper as an information medium to an input/output device of an information processing system. The present invention relates to an improvement of an automatic paper feeder equipped with a paper separation mechanism.

-Summary of the invention- This invention is a paper feeding device equipped with a friction pad type paper separation mechanism, in which a presser roller is loosely fitted onto the roller shaft of the feed roller, and the presser roller presses down the paper. This prevents the second and subsequent sheets of paper on the table from contacting the feed roller and being unnecessarily fed.

-Prior Art- In an automatic paper feeder that automatically feeds sheets of paper loaded on a paper tray, a so-called friction pad separates the paper to be fed by passing it between a roller and a friction pad. A type of paper separation mechanism is known.

Figures 4 and 5 show an example of an automatic paper feeder equipped with a friction pad type paper separation mechanism.
1 is a paper tray, 2 is a sheet of paper stacked on the paper tray 1, 3 is a feed roller, 4 is a friction pad that is in contact with the feed roller 3 by the urging force of a spring 5, and 6 is a sheet of paper stacked on the paper tray 1. This is a front edge guide plate, and in the illustrated example, this front edge guide plate 6 is bent at the upper part, and the bent portion 6a serves as a paper feeding guide.

In the state shown in FIG. 4 in which the paper table 1 has moved upward, the leading edge of the topmost paper 2a on the paper table is in contact with the feed roller 3, and by rotating the feed roller 3 in the direction of the arrow in the figure, The paper 2a is sent out to the left side of the figure. At this time, the second and subsequent sheets of paper on paper tray 1 are also sent out, but paper 2
When paper a passes between the feed roller 3 and the friction pad 4, the second and subsequent sheets are prevented from being sent out by the frictional force of the friction pad 4, and in the end only the topmost sheet is separated. They are sent out.

The fed sheet 2a is held between, for example, feeding rollers 11 of a printer device, and is given a line feed by the feeding roller 11. During this line feeding, the paper 2a is held by the feeding roller 3 and the friction pad 4. In order to avoid load resistance acting on the paper due to contact with A structure is adopted in which the friction pad 4 is separated from the delivery roller 3.

-Problem to be Solved by the Invention- However, due to the feeding operation, the leading edge of the second sheet 2b on the paper tray has advanced to the position of the friction pad 4, so when the paper tray 1 is lowered, , the paper 2b often remains in a slanted state as shown in FIG. Then, when the trailing edge of the fed paper 2a leaves the feeding roller 3, the leading edge of the second sheet 2b comes into contact with the feeding roller 3.

Generally, the feed roller 3 shares a drive source with the feed roller 11 in order to simplify the drive mechanism, and with such a structure, the first sheet of paper 2a that is fed out Even after the rear end leaves the feed roller 3, the feed roller 3 rotates along with the rotation of the feed roller 11, and at this time, the fifth
It happens that the second sheet 2b, which is in the state shown in the figure, is sent out unnecessarily. This unnecessary feeding of the second sheet 2b tends to occur particularly frequently when the sheet 2 is a postcard or the like.

In particular, in an apparatus in which the feed roller 11 is rotated in the opposite direction while the feed roller 3 is rotated to feed out the paper 2a in order to correct the skew of the paper being fed, the paper 2a is processed from the feed roller 11. When the feed roller 11 is reversely rotated to send the finished paper back toward the paper ejection path 12 above, the feed roller 3 will continuously rotate in the forward direction. A problem arises in that the second sheet of paper 2b is sent out all at once.

This invention aims to solve the above problem, and includes a paper separation mechanism that prevents the possibility of the second or subsequent sheets being sent out even if the delivery roller 3 rotates at times other than the normal paper feeding. The objective is to obtain an automatic paper feeder with a

-Means for solving the problem- In order to solve the above problem, the printer of this invention is provided with a presser roller 8 that is loosely fitted to the roller shaft 7 of the feed roller 3.
The roller shaft has a clearance 9 such that when the paper table 1 is lowered and the friction pad 4 is separated from the feed roller 3, the lower end circumferential surface 8a of the feed roller 3 hangs below the lower end circumferential surface 3a of the feed roller 3. 7 is loosely fitted.

-Function- When the paper tray 1 is lowered and the friction pad 4 is separated from the feed roller 3, the holding roller 8 descends due to its own weight and holds the second and subsequent sheets of paper that have advanced to the area of the friction pad 4. Since the tip of the sheet 2b is forcibly separated from the circumferential surface 3a of the feed roller 3, no matter how much the feed roller 3 rotates in this state, the second and subsequent sheets of paper 2b will not be sent out.

-Embodiment- Figures 2 and 3 show the main parts of the first and second embodiments of this invention. 8
A loosely fitted structure is shown. The above-mentioned corresponding clearance means, as described above, a clearance sufficient to allow the lower end circumferential surface 8a of the presser roller 8 to hang down below the lower end circumferential surface 3a of the feed roller 3. The three feed rollers 3 shown are of course fixed to the roller shaft 7, and although not shown in FIGS. 2 and 3,
Immediately below each feed roller 3, opposing friction pads 4 are provided.

The pressure roller 8 provided in this way hangs down due to its own weight in the state shown in FIG. 1 when the paper table 1 is lowered and the friction pad 4 is separated from the feed roller 3.
The leading edge of the second and subsequent sheets of paper 2b, which are held obliquely as shown in FIG. 5, is pushed down to separate the leading edge from the feed roller 3 as shown in FIG.

In the embodiment shown in FIG. 2, the presser rollers 8 are provided only on both sides of the left-most feed roller 3. Normally, the structure shown in FIG. 2 can prevent the second and subsequent sheets from being sent out, but If you want a reliable structure, use the press roller 8 as shown in FIG.
It is sufficient to adopt a structure in which the rollers are provided on both sides of each of the feed rollers 3.

-Effects of the invention- With the structure described above, in the automatic paper feeder of this invention, when the paper tray descends, the second and subsequent sheets of paper that have advanced to the bottom of the feed roller are removed from the feed roller by the holding roller. Since the paper is forcibly separated, even if the feed roller rotates along with the feed roller, it is possible to completely prevent the paper from being sent out at times other than the normal paper feeding time. can. The pressure roller may be a simple disc;
Since it is sufficient to simply loosely fit the roller shaft of the feed roller, there is no increase in the cost of the device, and there is an effect that unnecessary feeding of paper can be completely prevented with a simple structure.

[Brief explanation of the drawing]

Figures 1 to 3 are diagrams showing an embodiment of this invention. Figure 1 is a side view showing the paper feeder with the paper tray lowered, and Figure 2 is a schematic diagram showing the mounting structure of the presser roller. FIG. 3 is a perspective view of the main part showing another mounting structure for the pressing roller. 4 and 5 are side views showing the conventional apparatus, with FIG. 4 showing the state when paper is fed, and FIG. 5 showing the state when the load on the fed paper is released. In the figure, 1: Paper table, 2: Loaded paper, 3: Feeding roller, 3a: Its lower end circumferential surface, 4: Friction pad, 7: Roller shaft, 8: Holding roller, 8a: Its lower end circumferential surface, 9: Idle. Gap.

Claims (1)

[Claim for Utility Model Registration] It has a paper separation mechanism that separates paper by passing it between a feed roller of a paper feeding device and a friction pad pressed against it, and after the paper is fed out, the paper is separated. In an automatic paper feeder in which the table lowers relative to the feed roller and the friction pad and the feed roller are separated to release the feeding load on the paper, the presser roller 8 moves the paper table 1 and the friction pad 4
is loosely fitted onto the roller shaft 7 of the feed-out roller 3 with a clearance 9 such that the lower end circumferential surface of the feed-out roller 3 hangs below the lower end circumferential surface of the feed-out roller 3 when the roller is lowered and separated. An automatic paper feeder that is characterized by: