JPH0338174B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a paper feeding method in a paper feeding device that automatically supplies cut sheets, which serve as information media, to a copying machine or an information processing device.

●Technical Background Cut sheets inserted into copying machines and printers of information processing devices are fed while being held between paper feed rollers. Therefore, when automatically feeding cut sheets to these devices, it is necessary to separate the stacked sheets one by one and feed them into the paper feed roller.
A normal automatic feeding mechanism has a paper feed roller that rotates in contact with the top surface of the stacked paper, and the paper fed out by the frictional driving force of this paper feed roller is held by a locking pawl, friction pad, etc. The paper is separated and sent to the gripping part of the paper feed roller.

●Prior art and problems In a conventional paper feeding device having such a paper feeding roller and paper feeding roller, the paper is fed out from the paper feeding roller while both the paper feeding roller and the paper feeding roller are rotating. Either let the paper be caught in the paper feed roller as it is, or with the paper feed roller stopped, let the front edge of the paper sent out from the paper feed roller come into contact with the biting part of the paper feed roller, and then feed the paper. The paper feeding force of the rollers is released and only the paper feeding rollers are rotated to catch the paper. However, according to the former method, when the paper is fed out at an angle by the paper feed roller, the paper gets caught in the paper feed roller as it is, resulting in skewed printing in printers, etc.
According to the latter method, although the inclination of the paper being fed is corrected, there is a problem in that when thick paper is used as the paper, the paper is not caught by the paper feed roller, and paper feeding errors often occur. In this case, if the paper feeding force of the paper feed roller is not released even after the paper has been delivered to the paper feed roller, the paper will be Problems such as jams occur, feeding errors occur when the paper feed roller side is fast, and the paper tilts again.

●Purpose of the Invention This invention was made in order to solve the problems of the above-mentioned conventional means.It has a function of correcting the inclination of the fed paper, and also has a function to automatically straighten the paper even if the paper is thick paper. This paper is intended to provide a paper feeding method that can supply paper.

●Structure of the invention The paper feeding method of this invention is based on the paper feeding method of the invention.
5a, and a paper feed roller 16 that rotates in contact with the upper surface of the stacked paper 35 to feed the paper to the paper feed roller 6a; Preferably paper feed roller 1
6 and paper feed roller 6a are connected to pulse motors 11 and 2.
This is adopted in an automatic paper feeder having a structure in which the paper feeder is driven by 7.

In the method of the present invention, the leading edge of the paper sent out by the paper feeding roller 16 is brought into contact with the biting part 39 of the paper feeding roller 6a, which is stopped or driven in reverse. After this first operation, a second operation of temporarily stopping the paper feed roller 6a and the paper feed roller 16, and a second operation of temporarily stopping the paper feed roller 6a and the paper feed roller 16. A third operation of rotating the roller 16 at a low speed at the same circumferential speed, and a third operation of rotating the roller 16 at a low speed at the same circumferential speed, and a third operation of rotating the roller 16 at a low speed with the same peripheral speed, and after the paper is caught in the paper feed roller 6a, the paper feed roller 6
The present invention is characterized in that the fourth operation of rotating the roller a at high speed and releasing the paper feeding force of the paper feeding roller 16 is performed in the above order.

●Embodiments of the invention Next, embodiments shown in the drawings will be described. The embodiment shown in the figure shows an example in which the method of the present invention is applied to an automatic paper feeder of a printer of an information processing device, and FIGS. 1 and 2 are side views of main parts of the automatic paper feeder. and a plan view, and FIGS. 3 to 6 are side views showing the operation of the method of this invention.

In Figures 1 and 2, 1 is a platen, 2 is a platen shaft, 3 is a printing head, 4 is a printing position, 5 is a pulley fixed to the platen shaft 2, 6a and 6b are paper feed rollers, and 7a and 7b are their Drive roller, 8a, 8
b is the drive roller shaft, 9a and 9b are the drive roller shafts 8
pulleys fixed to a and 8b, 10a a driven roller of the paper feed roller 6a, 11 a pulse motor, 1
2 is a pulley fixed to the output shaft of the pulse motor 11, 13 is a timing belt wound between the pulleys 5, 9a, 9b, and 12, and 14 is a paper feed roller 6.
15 is a paper detection sensor arranged on the paper supply side of paper feed roller 6a; 16 is a paper feed roller consisting of a separation roller 17 and a pick roller 18; 19 is a separation roller. a shaft; 20 is an arm swingably mounted around the separation roller shaft 19; 21 is a pick roller shaft pivotally attached to the arm 20; 22 and 23 are pulleys fixed to the separation roller shaft 19 and the pick roller shaft 21, respectively; 24 is pulley 22, 23
25 is a pulley attached to the separation roller shaft 19 via a one-way clutch 26; 27 is a pulse motor; 28 is a pulley fixed to the output shaft of the pulse motor 27;
9 is a timing belt wound between pulleys 25 and 28; 30 is a bracket mounted swingably around a pin 31; 32 is a friction pad fixed to the bracket 30 and pressed against the separation roller 17; 33; is a spring that biases the friction pad 32,
34 is a hopper table that moves up and down, 35 is a cut sheet stacked on the hopper table 34, and 36 is a stacked sheet sheet 35.
37 is the hopper stand 3 which guides the front edge of the front plate.
A limit switch 38 detects the upward movement position of the arm 20 by swinging the arm 20, and a stopper 38 restricts the downward position of the arm 20.

The paper feed rollers 6a and 6b have a structure in which a drive roller 7 that is pivoted at a fixed position and a driven roller 10 that is movable up and down and is pressed by the drive roller 7 sandwich and feed the paper. It is driven by a pulse motor 11. The separation roller 17 of the paper feed roller 16 is pivoted at a fixed position, and the pick roller 18, which moves up and down by swinging around this axis, comes into contact with the upper surface of the stacked paper 35 by its own weight or by a suitable spring. When the paper feed roller 16 is driven by the pulse motor 27, the pick roller 18 uses its frictional force to feed out the stacked papers, and the separation roller 17 and friction pad 32 separate the papers to separate the papers into the topmost one. Only the paper is sent out toward the biting portion 39 of the paper feed roller 6a.

Next, the paper feeding method of the present invention will be explained with reference to FIGS. 3 to 6.

First, the hopper stand 34 is raised to a position where the limit switch 37 is activated, and the stacked paper 35 and the pick roller 18 are brought into contact with each other. Next, paper feed roller 1
6 and remove the topmost sheet 35 of the stacked paper 35.
a toward the biting portion 39 of the paper feed roller 6a. After the leading edge of the fed paper 35a is detected by the sensor 15 (FIG. 3), the paper feeding roller 16 is rotated by a predetermined amount to stop or reverse the leading edge of the paper 35a. It is brought into contact with the biting part 39 (Fig. 4). At this time, paper 3
If the paper 5a is thin, the paper 3
5a comes into contact with the paper feed roller 6a in a bent state,
The skew (oblique feeding) of the paper 35a is corrected. Further, when the paper 35a is thick, the paper feed roller 16 slips when the paper 35a comes into contact with the paper 35a as shown in FIG. 4B, and the skew of the paper 35a is corrected. If the paper feed roller 6a is reversed when the paper 35a comes into contact with the paper 35a, the skew correction function can be more effectively performed.

After temporarily stopping the paper feed roller 6a and the paper feed roller 16 in the state shown in FIG.
6 and the paper feed roller 6a are rotated at low speed at the same circumferential speed so that the leading edge of the paper 35a is caught in the paper feed roller 6a. When the leading edge of the paper 35a is detected by the sensor 14 (FIG. 5), the pulse motor 27 is stopped and the hopper table 34 is lowered to increase the driving force of the paper feed roller 16 and the pick roller 18 and the stacked paper. 35 and rotates the paper feed roller 6a at high speed to feed the paper 35a to the printing position 4 (FIG. 6). At this time, since the separating roller 17 rotates with the paper 35a being pulled out, a one-way clutch 26 is provided to release this rotational resistance.

FIG. 7 shows the state of the drive pulses applied to the pulse motors 11 and 27 during the above paper feeding operation. The paper feed pulse is a pulse given to the pulse motor 27, the paper feed pulse is a pulse given to the pulse motor 11, the feeding and jamming detection pulses are paper detection pulses from the sensors 15 and 14, and A indicates that the leading edge of the paper 35a is Paper feed roller 6a
B is a period during which the paper feed roller 6a and paper feed roller 16 are rotated at low speed in order to cause the paper 35a to be caught in the paper feed roller 6a. In the figure, the pulse P is shown in the opposite direction because the paper feed pulse is driven by pulse motor 1.
This shows that it is given in the reverse direction of 1. As shown in the figure, when the paper is caught, the roller 6
If a and 16 are rotated at low speed, paper feed roller 1
Since intermittent pulses are applied to the paper 35a to apply a pulsating pushing force to the paper 35a, the paper 35a can be reliably caught in the paper feed roller 6a.

●Effects of the Invention According to the device of the present invention described above, even if the paper is fed out at an angle by the paper feed roller, the inclination can be corrected when the paper is bitten by the paper feed roller, so that it can be used easily. It is possible to obtain a paper feeding device that can reliably feed the stacked paper into the paper feeding roller regardless of the thickness of the paper, and can be used not only for commonly used office paper but also for postcards, envelopes, etc. It is possible to obtain a printer or a copying machine that can perform automatic paper feeding processing.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Fig. 1 is a side view with the roller drive mechanism and paper feed roller on the paper ejection side omitted, and Fig. 2 is a driven roller and hopper stand of the paper feed roller. FIGS. 3 to 6 are side views showing the operation, and FIG. 7 is a diagram showing the state of pulses applied to the pulse motor during paper feeding. In the figure, 1 is a platen, 3 is a printing head, 6a,
6b is a paper feed roller, 11 is a pulse motor, 13
is a timing belt, 14 is a paper detection sensor, 1
6 is a paper feed roller, 17 is a separation roller, 18 is a pick roller, 24 is a timing belt, 26 is a one-way clutch, 27 is a pulse motor, 29 is a timing belt, 32 is a friction pad, 34 is a hopper stand, 35 is a stacking unit 35a is a paper sheet to be fed, 37 is a limit switch, 38 is a stopper, and 39 is a biting portion.

Claims (1)

[Claims] 1. An automatic machine having a paper feed roller 6a that nip and feed the paper 35a and a paper feed roller 16 that rotates in contact with the upper surface of the stacked paper 35 and feeds the paper to the paper feed roller 6a. In the paper feeding method of the paper feeding device,
A first operation in which the leading edge of the paper sent out by the paper feed roller 16 comes into contact with the biting part 36 of the paper feed roller 6a which is stopped or driven in reverse; and a first operation in which the paper feed roller 6a and the paper feed roller 16 are brought into contact. A second operation in which the paper feed roller 6a and the paper feed roller 16 are rotated at low speed at the same circumferential speed; A second operation in which the paper feed roller 6a and the paper feed roller 16 are rotated at low speed at the same circumferential speed; and After the paper is caught in the paper feed roller 6a, the paper feed roller 6a A method for feeding paper, characterized in that the fourth operation of rotating the paper feed roller 16 at high speed and releasing the paper feeding force of the paper feed roller 16 is performed in the above order.