JPS60244733A - Paper feeder - Google Patents

Abstract

PURPOSE:To facilitate the positioning of a pad, by attaching the pad to a bracket through a spring, and using the force of the spring to bring the pad into contact with a core between rollers. CONSTITUTION:A core 8 of small diameter is rotatably supported between paper feed rollers 6 concentrically thereto. A bracket 2 is provided in the face of the bottom of each paper feed roller 6. A pad 4 is attached to th bracket 2 through a spring 3 such as a helical spring so that the top of the pad is placed in the trough 7-1 between the rollers 6 and pushed on the core 8 by the force of the spring 3. Paper 9 sent out from a paper feed cassette by the rollers 6 comes in between the pad 4 and the core 8 so that the paper is partly bent protrusively by the depth of the trough 7-1 and the protrusively bent portion of the paper is pushed on the surface of the core 8 by the pad 4. As a result, only one sheet of paper 9 is conveyed out by the frictional force caused between the sheet and the rollers 6 along with the rotation of the rollers.

Description

Detailed Description of the Invention (Field of Application) The present invention relates to a paper feeding device for supplying paper to copiers, automatic printers, etc. It concerns what makes paper possible.

(Prior art) In a paper feed device that supplies paper from a paper feed cassette or paper feed tray in a copying machine or an automatic printer, there is a conventional separation mechanism for preventing paper from being fed multiple times. Therefore, a snubber type and a retard type are used. Among the above-mentioned retard systems, a friction retard system and a corrugation retard system have recently been devised for use in small-sized copying machines, and these systems tend to be widely used.

Here, the corrugation retard method, as shown in Figure 1 (a) and (b), consists of a plurality of paper feed rollers 6.6°... By fixing the pads 4 at predetermined intervals and arranging them so that a high friction member such as the pad 4 enters the gap 7 between the rollers, the pad 4
The handling performance of the paper 9 changes depending on the amount of intrusion from the surface of the roller 6.

Therefore, when using such a mechanism, the pad 4
It must be set so that the amount of penetration is an appropriate value. In particular, when paper feed current 1 is used, in order to avoid leaving paper 9 caught between paper feed roller 6 and pad 4 when removing cassette 1, it is necessary to Interlockingly, a mechanism for lowering the pad 4 must be installed, and the mechanism must be assembled accurately.

Furthermore, even when other paper feeding systems are used, they naturally have many drawbacks, such as the need to provide various adjustment mechanisms and perform extra work such as positioning them.

(Purpose) The present invention provides a corrugation retard type paper feeding device that automatically sets the amount of biting of a pad that is provided to fit between rollers, and facilitates separation (many attachments and positioning). The purpose is to

(Structure) The paper feeding device of the present invention includes rollers fixed to a shaft at regular intervals and a small-diameter core rotatable with respect to the shaft, provided between the rollers. A pad is attached via a spring to the bracket 1 provided facing downward from the roller, so that the upper surface of the pad comes into contact with the core.

Then, the paper taken out from the paper feed cassette by the rollers is conveyed by the feed rollers with a portion of the paper being sandwiched in the trough between the core and the pad in a mountain shape. Therefore, when the paper is fed out, the peaks of the paper that enter the valleys between the rollers are pressed against the surface of the core by the pad, and only one sheet is pushed by the friction between the roller surface and the paper due to the rotation of the rollers. It will be sent.

(Embodiment) As shown in FIG. 2, the paper feeding device of the present invention includes a plurality of rollers 6, 6, etc. provided at predetermined intervals on a rotating shaft 5 provided in a paper feeding section of a copying machine. At the same time, a core 8 having a diameter smaller than that of the roller 6 is provided so as to be freely rotatable about the shaft. Therefore, a shallow valley 7-1 is formed between the rollers 6.6.

Furthermore, a bracket 2 is provided facing the lower part of the paper feed roller 6, and a coil spring 3 is attached to the bracket 2.
A pad 4 is provided via a spring member such as the like, and the upper portion of the pad 4 enters the valley 7-1 between the rollers and comes into contact with the core 8.

The paper 9 sent out from the paper cassette 1 by the roller 6 enters between the pad 4 and the core 8, and is partially bent into a mountain shape by the depth α of the trough 7-1 before being sent out by the roller. The paper 9 is conveyed by friction between the surface of the paper 6 and the paper 9.

When only one sheet of paper 9 is taken out from the paper feed cassette, the coefficient of friction on the surface of roller 6 is greater than the coefficient of friction on the surface of pad 4, so the paper 9 remains between the core 8 and the pad. transported. In addition, two sheets of paper 9
When the paper 9 is taken out from the cassette 1 in a stacked state, the frictional force of the upper paper 9 with the lower paper is smaller than the frictional force with the roller 6, so the paper 9 is sent out by the roller 6.
Since the lower paper comes into contact with the surface of the pad 4, it is prevented from advancing by its frictional resistance and the resistance to deformation when a portion of the paper is bent between the rollers by the amount of penetration α, and is prevented from advancing into the cassette. It will stop at . Therefore, it is possible to prevent two sheets of paper 9 from being sent out from the cassette 1 in duplicate.

Note that the spring 3 that presses the pad 4 of the handling member upward is strong enough to deform one sheet of paper and secure the amount of penetration α, and is also strong enough to prevent the advance of one sheet of paper. We use only a few.

Then, if the coefficient of friction of the roller 6 is μ, the pressing pressure thereof is N1, the friction coefficient of the separating member is μm, and the pressing force of the spring 3 is NR, the following relationship holds approximately.

μF
Due to the structure, the sheets 9 are taken out one by one from the cassettes 1 to 1 and supplied to the copying machine.

Further, in the present invention, as shown in FIG.
may be formed integrally with the roller 6. However, when the roller and core are integrally formed, when the roller idles, the load increases due to friction between the core and the pad, which requires the use of a motor with large torque. Friction between the pads increases wear on both.

Therefore, if the core is worn out, the set value for the amount of paper intrusion will be incorrect, and if the pad is worn out, its shape will change, making it impossible to obtain normal handling performance. For this reason, if the material of each member is made of a material that does not easily cause wear as described above, it would be difficult to use a roller and pad integrated. is very effective.

In the embodiment shown in FIG. 2, since the core 8 is rotatably provided separately from the roller 6, when the roller 6 idles, the core comes into contact with the pad 4 and is stopped, and the shaft 5 and roller 6 Since the rollers 6 only rotate, these contact members will not wear out due to idle rotation of the rollers 6.

Also, for the spring 3 that suppresses the pad 4 toward the core 8, a coil spring of appropriate strength may be used.
Alternatively, by using an elastic body such as a leaf spring, it is possible to set the amount of force that bites into the gap 7-1 between the rollers and the pressure thereof to be appropriate.

Further, in the above-described embodiment, a bracket is attached to the frame of the copying machine and a pad is provided on the bracket, but in the present invention, Paragraph 1~ is integrated with paper feed force cell 1~. It is also possible to provide one.

In this case, it is sufficient to attach a pad to the tip of the paper feed cassette via a leaf spring so that the pad fits between the paper feed rollers and is positioned. By integrating the pad, even if paper is caught between the roller and the pad, the paper will be pulled out together with the cassette, and problems such as paper remaining between the rollers will not occur. do not have.

In the apparatus of the present invention, one or more sets of the pad and paper feed roller are provided depending on the width of the paper and the model of the copying machine. Of course, even if there are pads, it is not necessary to provide pads for all of them.

(Effects) Since the present invention has the above-described configuration, it is possible to automatically position the pads, and there is no need to make adjustments. Further, even when the cassette is removed, the paper will not be left between the rollers, and the paper will not be damaged.

In addition to the effects described above, the present invention allows multiple pads to be installed together via brackets when assembling the sorting member, so unlike conventional systems, multiple pads can be installed separately. It is possible to save the effort of making adjustments, etc., and it is possible to reduce the cost in manufacturing the copying machine.

[Brief explanation of drawings]

Figures 1 (a) and (b) are a front view and a side view showing a conventional example, and Figures 2 (a) and (b) are a front view and a side view of a paper feeding unit showing an embodiment of the present invention. Figure 3 (a),
(b) is a front view and a side view showing another embodiment. Reference numerals in the diagram: 1...Paper cassette, 2...Bracket, 3...Spring, 4...Pad, 5...Shaft, 6... ... Laura, 7.
...Gap between rollers, 8...Core,
9...Paper, (1 other person) 1st (a) 2nd (b) Diagram (b) 3rd r (b) Just

Claims (1)

[Claims] In a paper handling mechanism in which a plurality of paper feed rollers are fixed to a drive shaft at predetermined intervals, and a high friction member for sorting is arranged between these O-rollers, the paper feed 0-line is A small-diameter concentric core is rotatably provided in between, and a pad made of a high-friction member for handling is provided opposite to this core and is mounted on the bracket via a spring. A paper feeding device characterized in that the paper is pressed against a core with a constant pressure.