JPH01214528A - Paper feed mechanism - Google Patents

Abstract

PURPOSE:To reduce fluctuation of the upper set position of cut paper by providing slits for regulating the upper limit height automatically when a cut paper is fed and for reducing the table lift speed when papers are supplied or replaced. CONSTITUTION:When cut sheets 3 are fed continuously and the height of the sheets reaches to a lower limit B, a light shielding board 10 moves in the direction of an arrow to face a slit 11 with the optical path of a photo-interruptor 6, and the light emitted from a light emission element is received by a photoreceptor element to cause rotation of a motor 91 thus lifting a table 2. When a lever 4 is pushed up and the optical path of the interrupter 6 is shielded by the shielding board 10, the motor 91 is turned OFF to stop the table 2. When the table 2 is lowered farther than the lower limit in order to supply cut sheets 3 or to replace a cut sheet 3 having different shape, the optical path of the interrupter 6 faces with the slit 113 of the shielding board 10. When the cut sheets are mounted on the table 2 and the machine is operated, the optical path of the interrupter 6 is not shielded by the shielding board 10 and the motor 91 is turned ON to lift the table 2.

Description

[Detailed Description of the Invention] [Summary] Regarding the paper feeding mechanism of a printing device using cant paper, the present invention aims to reduce the inertia at the upper limit position of the cut paper by placing the cut paper on the paper mounting table. An upper limit consisting of a table on which a cut sheet such as a single form is placed, a table moving mechanism for moving the table up and down, a lever for detecting the upper limit position of the cut sheet on the table, a light shielding plate, and a photo interlayer. In a paper feeding mechanism equipped with a position detection mechanism, the light shielding plate of the upper limit position detection mechanism has a slit section for automatically adjusting the upper limit height of cut paper when feeding cut paper, and a slit section for automatically adjusting the upper limit height of cut paper when feeding cut paper, and a slit section for automatically adjusting the upper limit height of cut paper when feeding cut paper. A slit portion is provided to reduce the table rising speed.

[Industrial application field]

The present invention relates to a paper feed mechanism for cut sheets of a printing apparatus, and more particularly, to a paper feed mechanism that reduces variations in the upper limit position of stacked cut sheets.

In the field of information processing, printing devices are widely used as information output devices. Some of these printing devices use form-type printing paper (hereinafter referred to as cut paper). This type of printing device uses a paper feed mechanism that feeds paper. This paper feeding mechanism is a paper loading table (hereinafter referred to as a table).
A photointerrupter consisting of a pair of light-emitting and light-receiving elements is installed at the upper limit of the cut paper, and the cut paper is
- Although the upper limit of the paper is detected and the overrun of the double-layered table is prevented, the stopping position may vary due to the inertia when the table moving mechanism stops.

[Conventional technology]

FIG. 4 is a schematic perspective view illustrating a conventional paper feeding mechanism.

In the figure, a table 2 is attached to a heald 93 of a table moving mechanism 9 consisting of a motor 91, a pair of pulleys 92, and a heald 93, and is moved up and down by the drive of the motor 91. A cut sheet 3 such as a single form is placed on the table 2.

A mechanism 15 for detecting the upper limit position is provided on the top surface of the stacked cut sheets 3. This mechanism consists of a lever 4 fixed to one end of a shaft 5 and in contact with the surface of the cut paper 30, a light shielding plate 7 fixed to the other end of the shaft 5, and an optical path of a light emitting/light receiving element being opened and closed by the light shielding plate 7. It consists of a photointerrupter installed in the same way.

Further, eight Pino crawlers are pressed against the first two-part cut paper 3, so that the cut paper 3 is fed out one by one. The fed cut sheets 3 are sequentially sent to the printing section by a sheet feeding roller 12 attached to a pulley 13 which is rotated by a heald 14 in synchronization with the pick roller 8. When the loaded amount of cut paper 3 decreases due to this feeding, the lever 4 moves down in the direction of the arrow, and the light shielding plate 7 attached to the other end of the shaft 5 moves in the direction of the arrow. When the table 2 is removed from the optical path of the photointerrupter 6, the light from the light emitting element is received by the light receiving element, and the motor 91 of the moving mechanism is turned on by the output of the light receiving element and is driven in the direction of the arrow to raise the table 2.

When the lever 4 is pushed up by this rise and the cans 1 to 3 reach the upper limit position, the light shielding plate 7 blocks the optical path via the shaft 5, the motor 91 is turned off, and the table stops.

[Problem to be solved by the invention]

In the conventional paper feeding mechanism described above, when replenishing cut sheets or replacing cut sheets with different shapes, the table is lowered to a predetermined position, the cut sheets are loaded, and the moving mechanism is driven again after loading. At least raise it to the upper limit position. However, the amount of increase at this time is greater than during normal level adjustment, and the motor rotation speed reaches a certain rotation speed, so even if the upper limit of cut paper is detected and the motor is stopped, the view of the table and paper There has been a problem in that the inertia of the motor may cause overrun, exceeding the set upper limit position, resulting in mishandling or double feeding.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper feeding mechanism that reduces inertia and reduces variations in the set upper limit position of cut sheets.

[Means to solve the problem]

The present invention includes a table on which a cut sheet such as a single form is placed, a table moving mechanism that moves the table up and down, a lever that detects the upper limit position of the cut sheet on the table, a light shielding plate, and a photo interlayer. In a paper feeding mechanism equipped with an upper limit position detection mechanism, the light shielding plate of the upper limit position detection mechanism has a slit portion for automatically adjusting the upper limit height of cut paper when feeding cut paper, and a cutter I/paper portion. This problem is solved by providing a slit portion to reduce the table rising speed when replenishing or replacing the table.

[For production]

When raising the table after replenishing or exchanging the cut sheets, the table raising speed of the table moving mechanism is sufficiently slowed down because the detection output of the upper limit position detection mechanism is intermittent and the motor drive is also intermittent. , it is possible to stop at the upper limit position after the table-F wall speed reaches the same speed as continuous feeding, and the inertia at the time of stopping is reduced.

In claim 2, another detection mechanism detects the cut paper at a set position below the detection level of the upper limit position detection mechanism, and changes the table raising speed of the table moving mechanism to a low speed to achieve the same level as continuous feeding. Set to table rising speed.

FIG. 1 is a schematic perspective view illustrating an embodiment of the present invention. In FIG. 1, the paper feeding mechanism of the present invention is similar to FIG. 4, and is equipped with an upper limit position detection mechanism consisting of two paper feeding unit main bodies, a table, a cut sheet, a lever, a photo interlubber, a light shielding plate, a moving mechanism, etc. However, the feature is that the light shielding plate is improved. Therefore, parts other than the light shielding plate are given the same reference numerals as in FIG. 4, and explanations of these parts will be omitted here.

The light shielding plate 10, which characterizes the present invention, is fan-shaped as shown in FIG. 2, and has a plurality of slits 11 in its arcuate portion. The slits 11 have different widths, 111 is a slit for continuous feeding, 112 is a continuous slit,
113 is a table lowering position detection slit, and the interior 101 remains between each slit.

FIG. 2 is a front view illustrating the operation of this light shielding plate, and FIG. 2(a) shows the case where the lever is at the upper limit position.

(b) shows the case when the lever is at the set lower limit position, and (C) shows the case when the table is lowered.

FIG. 2 fal shows a case where the cut paper 3 is mounted on the table 2 and its two sides are at the setting upper limit position A. In this position, the light shielding plate 10 interlocked with the lever 4 Since the interior 101 blocks the optical path, the moving mechanism 9 (motor 91) is not energized and the table 2 is in a stopped state.

FIG. 2 (bl shows the case where the cut paper 3 is continuously fed out and the paper height reaches the lower limit of the set position B. In this position, the light shielding plate 10 interlocked with the lever 4 moves in the direction of the arrow, The slit 111 for continuous feeding is aligned with the optical path of the photo interlator 6. As a result, the light from the light emitting element is received by the light receiving element, and the output of the light receiving element turns on the motor 91 of the moving mechanism 9, which rotates the table. Raise 2.

When the lever 4 is pushed up by this rise and the optical path of the photointerlator 6 is blocked by the interior 101 of the light shielding plate 10, the motor 91 is turned off and the table 2 stops rising.

FIG. 2(C) shows a case where the table 2 is lowered below the lower limit of the set position in order to replenish the cut paper 3 or replace it with a cut paper 3 of a different shape. The optical path 6 faces the table lowering position detection slit 113 of the light shielding plate 10.

In this state, when the paper 3 is placed on the table 2 and the apparatus is put into operation, the optical path of the photo interlator 6 is not blocked by the light shielding plate ]O, so the motor 91
Turn on and raise table 2.

In this rising process, the optical path is
01, the motor 91 turns OFF and the table 2 stops rising.However, since the inside 101 is sufficiently thin, the overrun due to inertia when the motor 91 stops reaches the deceleration slit 112, and the motor 91 turns ON again. As a result, table 2 rises.

By repeating such ON-OFF operation of the motor 91, the rising speed of the table is reduced as a result, and the slit 111 for the next continuous feeding is opposed to the optical path of the photointerlurator 6. At this position, the same operation as when the cut paper 3 is continuously fed out as explained in FIG.

FIG. 3 is a diagram for explaining another embodiment of the present invention.
al is a schematic perspective view, and (b) is an explanatory diagram of the operation of the detection mechanism. This embodiment is characterized in that, in addition to the conventional structure shown in FIG. 4, a low speed travel switching position detection mechanism is provided. Therefore, the same reference numerals as in FIG. 4 are given to the parts other than the low speed travel switching position detection mechanism, and the explanation of these parts will be omitted here.

The low-speed travel switching position detection mechanism 16 that characterizes the present invention is as follows:
The upper limit of the cut paper 3 has reached a position slightly below the area where the table 2 moves up and down during continuous feeding of the cut paper 3 (between the paper setting position lower limit 8 and the setting position lower limit B) (low-speed running switching position). Upper limit position detection mechanism 15
It consists of a photointerturbator 6 having the same configuration as the one shown in FIG. Based on this detection output, motor control such as switching the rotational speed of the remote motor 91 from high speed to low speed or temporarily stopping and restarting the motor 91 is performed to slow down the rising speed of the table 2 and prevent overrun from occurring. This reduces inertia and makes it easier to stop at the set position.

In addition, although the slit 11 was formed in the light-shielding plate 10 in the said Example, it is not limited to the slit 11, but a window may be provided.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, the rising speed of the table is reduced near the set position of the paper, so the inertia is reduced, the variation in the set position is eliminated, and errors in paper feeding and double feeding are avoided. This can be prevented and reliability can be improved.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a schematic perspective view illustrating an embodiment of the present invention. FIG. 2 is a front view illustrating the operation of the light shielding plate of the present invention.
The same figure (if the lever is at the upper limit position, (b)
(C) is when the table is lowered. FIG. 3 is a diagram illustrating another embodiment of the present invention.
al is a schematic perspective view, (b) is a diagram illustrating the operation of the detection mechanism, and FIG. 4 is a schematic perspective view illustrating a conventional paper feeding mechanism.

Claims (2)

[Claims] (1) A table (2) on which a cut sheet (3) such as a single form is placed, a table moving mechanism (9) that moves the table (2) up and down, and a table moving mechanism (9) that moves the upper limit position of the cut sheet on the table. Upper limit position detection mechanism (
15), the light shielding plate (10) of the upper limit position detection mechanism (15) has a slit portion (11) for automatically adjusting the upper limit height of cut paper when feeding cut paper.
1) and a slit section (112) for reducing the table rising speed when replenishing or exchanging cut sheets (3). (2) A table (2) on which a cut sheet (3) such as a single form is placed, a table moving mechanism (9) that moves the table (2) up and down, and a table that moves the upper limit position of the cut sheet on the table. Upper limit position detection mechanism (
15), in addition to the upper limit position detection mechanism (15), the cut paper (3) detected by the upper limit position detection mechanism (15) is
A mechanism (16) is provided for detecting the height of the cut paper at a position below the height level of the table, and the table lifting speed of the table moving mechanism (9) is switched to a low speed based on the detection output of the detection mechanism (16). A paper feeding mechanism according to claim (1).