KR20000051019A - Paper sending apparatus for electrophotographic printer - Google Patents

Abstract

Disclosed is a paper feeding apparatus for an electrophotographic printer. The paper feeding apparatus of the disclosed electrophotographic printing press is driven by a predetermined driving source and a pickup roller for pushing out the paper stored in the cassette, and the driven roller is driven by the driving direction in the same direction as the rotational direction of the body. In the sheet feeding apparatus of the electrophotographic printing press equipped with a guide roller for guiding the paper picked up by the feeding roller, the guide roller is provided to cover the inner ring portion rotated by the drive source, and the inner ring portion is the inner ring The outer ring portion is provided when the body is rotated by the drive source, the body is caught in the inner ring portion and rotated together with the outer ring portion, the driving source is intermittent and at the same time the driving direction of the paper in response to the running of the paper bitten by the feeding roller Paper fed to the feeding roller unlike the conventional one by being driven only in the same direction Inhibit the pick-up roller driven by the drive to have the advantage in that it can prevent the occurrence of jam (jam).

Description

Paper sending apparatus for electrophotographic printer

The present invention relates to a paper feeder for an electrophotographic printing press, and in particular, an electrophotographic method that can prevent jams caused by a pick-up roller driven by a guide roller driven by a sheet of paper fed to a feeding roller. A paper feeding device.

In general, an electrophotographic printing machine such as a color laser printer or a copying machine is a device for printing a desired image by developing an electrostatic latent image formed on a photosensitive medium such as a photosensitive belt with a developer having a predetermined color and transferring it to a paper. Such a printer is provided with paper feeding means for performing a printing process while sequentially supplying paper into the main body.

1 is a schematic diagram showing a paper feeding apparatus of a conventional electrophotographic printer.

Referring to FIG. 1, a paper feeding device of a conventional electrophotographic printing press is inserted and detachably coupled to one side of a printer main body 10, and a cassette 20 in which a plurality of sheets S are accommodated therein; A pickup roller 11, a guide roller 12, and a feeding roller 13 for drawing out the sheets S stored in the cassette 20 one by one and supplying the sheet S into the main body 10, and the cassette 20. Rotatably provided in the interior thereof and rotated by a knock-up plate 21 for lifting the leading end of the paper S toward the pickup roller 11, and by a predetermined driving source (not shown). And a lifter 15 for rotating the knock-up plate 21 toward the pickup roller 11. Here, the pickup roller 11, the guide roller 12 and the feeding roller 13 are rotatably installed by a single drive motor (not shown).

In such a configuration, when the cassette 20 containing the paper S is coupled to the main body 10, the lifter 15 rotates to lift the knock-up plate 21. Thereafter, when the knock-up plate 21 is gradually raised to reach the paper feed position, the pickup roller 11 is rotated clockwise in the drawing to be in close contact with the paper S. As shown in FIG. When the pickup roller 11 rotates while the paper S is in close contact, the paper S stored in the cassette 20 is bitten by the guide roller 11 one by one, and then a pair of feeding rollers 13 It is fed to and supplied inside.

2 is a view for explaining the driving of the pickup roller and the guide roller of FIG.

Referring to FIG. 2, in order to drive the pickup roller 11 and the guide roller 12 as described above, an electromagnetic clutch 24 for controlling power transmission to the rotating shaft 12a of the guide roller 12 is assembled. The driving device is coupled to the electromagnetic clutch 24.

The drive device includes a drive motor 22 capable of transmitting rotational force to the pickup roller 11 and the guide roller 12, and a drive gear 23 provided on the power take-off shaft of the drive motor 22. Then, the electromagnetic clutch 24 is provided with a driven gear 25 coupled to the rotation shaft 12a of the guide roller 12 and driven by the drive gear 23. In addition, a first gear portion 26 driven by the rotation of the driven gear 25 is provided on the rotation shaft 12a between the electromagnetic clutch 24 and the guide roller 12, and the shaft of the pickup roller 11 is provided. A second gear portion 27 driven by the first gear portion 26 is provided. In addition, the first roller portion 26 of the guide roller 12 and the second gear portion 27 of the pickup roller 11 are engaged with each other to guide the guide roller 12 and the pickup roller 11 in the same direction. A relay gear 28 geared to rotate is provided.

In such a configuration, when the paper S comes into close contact with the pickup roller 11, the guide roller 12 is rotated in one direction by the driving device, and the pickup roller 11 also has a guide roller 12. Driven in the same direction. As a result, the paper S enters the pair of guide rollers 12 by the pickup roller 11, and the paper S passing through the guide roller 12 is fed to the first feeding roller 13 so as to be internal. Is supplied. At this time, the electromagnetic clutch 24 interrupts the driving of the guide roller 12 after one sheet of paper S is fed into the guide roller 12.

By the way, when the paper S passing through the guide roller 12 is conveyed toward the feeding roller 13, the paper S is simultaneously bitten by the feeding roller 13 and the guide roller 12. Then, the feeding roller 13 is continuously rotated by a single drive source, that is, the drive motor 22, the guide roller 12 is driven to the paper (S) running even if the power is interrupted by the electromagnetic clutch 24. Driven and rotated. At this time, the pickup roller 11 is driven by the guide roller 12 to rotate in the same direction as the guide roller 12. Thereafter, the pickup roller 11 picks up to the next sheet S, and the picked sheet S is engulfed by the guide roller 12, which may eventually cause jams.

The present invention was created to improve the above problems, the feeding of the electrophotographic printing machine that can prevent the jam caused by the pickup roller driven by the guide roller driven by the running of the paper fed to the feeding roller The object is to provide a device.

1 is a schematic view showing a paper feeding apparatus of a conventional electrophotographic printing press,

2 is a schematic view for explaining the driving of the pickup roller and the guide roller of FIG.

3 is a schematic view showing a paper feeding apparatus of an electrophotographic printing press according to the present invention,

4 is a schematic view for explaining the driving of the pickup roller and the guide roller of FIG.

<Explanation of symbols for the main parts of the drawings>

10,100 ... Printing machine main body 11,111 ... Pick-up roller

12,112 ... Guide Roller 13,113 ... Feeding Roller

15,115 ... lifter 20,120 ... cassette

21,121 Knock-up plate 22,122 Drive motor

23,123 Drive Gear24,124 Electronic Clutch

25,125 ... driven gear 26,126 ... gear 1

27,127 ... 2nd gear part 28,128 ... relay gear

212 ... inner ring 312 ... outer ring

412 ... one-way bearing

In order to achieve the above object, the feeding device of the electrophotographic printing machine according to the present invention is a pickup roller for pushing the paper stored in the cassette, and is driven by a predetermined driving source. A paper feed apparatus of an electrophotographic printing press which is driven in the same direction and is provided with a guide roller for guiding the paper picked up by the pickup roller toward the feeding roller, wherein the guide roller is rotated by the driving source. And an outer ring portion which is installed to cover the inner ring portion and the inner ring portion is rotated by the driving source so that the body is caught by the inner ring portion and is rotated together, wherein the outer ring portion is clamped by the feeding roller while the driving source is interrupted. Driven in the same direction as the traveling direction of the paper in response to the The features.

According to the present invention, it is preferable that a one-way bearing is installed between the inner ring portion and the outer ring portion.

Therefore, by adopting a one-way bearing to the guide roller for feeding the paper to the feeding roller, unlike the related art, it is possible to prevent the pick-up roller from being driven by traveling of the paper fed to the feeding roller, thereby preventing the occurrence of jam. It has that feature.

With reference to the accompanying drawings with this feature will be described in detail the paper feeding apparatus of the electrophotographic printer according to the present invention. Here, other components except for the guide roller () are the same as the conventional one will be described briefly.

3 is a schematic view showing a paper feeding apparatus of an electrophotographic printer according to the present invention, Figure 4 is a schematic view for explaining the driving of the pickup roller and the guide roller of FIG.

Referring to FIG. 3, a paper feeding device of an electrophotographic printer according to the present invention includes a cassette 120 in which paper S is stored, and a pickup for extracting paper S one by one and supplying the paper S into the main body 100. The roller 111, the guide roller 112 and the feeding roller 113 is installed. Here, the knock-up plate 121 for lifting the tip end portion of the paper S toward the pickup roller 111 and the knock-up plate 121 are rotated to lift the pickup roller 111 toward the pickup roller 111. The lifter 115 is mounted.

In addition, to drive the pickup roller 111 and the guide roller 112, a driving device and an electromagnetic clutch (124 of FIG. 4) are provided.

The cassette 120 is installed to be inserted and withdrawn on one side of the printer main body 100, and is provided to accommodate the paper S to be printed therein. The pickup roller 111 draws out the sheet S stored in the cassette 120 one by one and feeds the sheet S to the guide roller 112 and the feeding roller 113, which will be described later. And is liftably mounted to be in contact.

A pair of the guide roller 112 is characterized in that the present invention is installed on one side of the pickup roller 111, the printing unit of the printer (100) picked up and pulled out of the pickup roller 111, the printing unit of the printer main body 100 To feed. Unlike the related art, the guide roller 112 includes a one-way bearing (412 in FIG. 4).

The feeding roller 113, that is, the pair of feeding rollers 113 shown in the drawing is the first for feeding the paper S into a printing unit (not shown), and the driving motor described later (Fig. 4). 122) to be rotated. The lifter 115 is rotated by a predetermined driving source (not shown) to lift the knock-up plate 121 of the cassette 120 so that the paper S is in close contact with the outer circumference of the pickup roller 111. Is installed.

On the other hand, referring to Figure 4, the drive device is provided with a drive motor 122, a drive gear 123 is installed on the power take-off shaft of the drive motor 122. Here, the drive motor 122 is installed to also drive the feeding roller (113 in FIG. 3) as described above. The electromagnetic clutch 124 is installed at one end of the guide roller 112 rotating shaft 112a and is provided to intermittently drive the guide roller 112. The outer circumference of the electromagnetic clutch 124 is coupled to the rotary shaft 112a of the guide roller 112, the driven gear 125 is driven by the drive of the drive gear 123 is coupled. In addition, on the rotation shaft 112a between the electromagnetic clutch 124 and the guide roller 112, a first gear portion 126 driven by rotation of the rotation shaft 112a according to the follower of the driven gear 125 is provided. The second gear part 127 driven on the shaft of the pickup roller 111 in response to the rotation of the guide roller 112 so that the pickup roller 111 can be rotated by the driving of the first gear part 126. Is installed. In addition, a relay gear 128 is provided for gear connecting the first gear 126 of the guide roller 112 and the second gear 127 of the pickup roller 111 to rotate in the same direction.

The guide roller 112, which characterizes the present invention, is provided with an inner ring portion 212 coupled to the rotating shaft 112a, and an outer ring portion 312 provided to cover the inner ring portion 212. Between the inner ring portion 212 and the outer ring portion 312 is rotated together with the outer ring portion 312 when the inner ring portion 212 is rotated by the driven gear 125 to drive the pickup roller 111 Only the outer ring portion 312 by rotating the paper S bitten by the feeding roller (113 in FIG. 3) while the pickup roller 111 is stopped by the driving interruption of the electromagnetic clutch 124. A one-way bearing 412, which is a known element, is installed to rotate in the same direction as the rotational direction of the inner ring portion 212 to be driven.

Hereinafter, the operation and action of the paper feeding device of the electrophotographic printer according to the present invention will be described in detail.

Referring to FIGS. 3 and 4, when the cassette 120 containing the paper S is inserted into the main body 100 of the printer, the lifter 115 is rotated and the knock-up plate of the cassette 120 is inserted. (121) Lift up. Thereafter, the paper S reaches the paper feed position toward the pick-up roller 111, and the pick-up roller 111 is lowered toward the front end of the paper S to be in close contact with each other.

Then, the driving motor 122 rotates the drive gear 123, and the drive gear 123 drives the driven gear 125 installed in the electromagnetic clutch 124. At this time, the feeding roller 113 is in a state of being continuously rotated by the drive motor 122. When the driven gear 125 is rotated, the rotating shaft 112a of the guide roller 112 is rotated, and the first gear 126 is also rotated to rotate the guide roller 112. At this time, since the one-way bearing 412 is provided on the outer circumference of the inner ring portion 212, the inner ring portion 212 is rotated in the counterclockwise direction, as shown in the drawing, so that the outer ring portion 312 ) Is also rotated with the inner ring portion 212. The rotation of the guide roller 112 by the rotation of the first gear 126 is driven to rotate the second gear 127 of the pickup roller 111, the first gear 126 and the second gear Since the relay gear 128 is provided between the 127, the pickup roller 111 is rotated in the same direction as the guide roller 112. Thus, the pickup roller 111 is rotated in the same direction as the rotation direction of the guide roller 112, and pushes a sheet of paper S in close contact with the body of the pickup roller 111 toward the guide roller 112. The guide roller 112 bites the sheet S and feeds the sheet S toward the first feeding roller 113 which is being rotated by the driving motor 122. Here, in the pickup roller 111 which pushes the paper S to the guide roller 112, the driven clutch is stopped by the electromagnetic clutch 124 intermittent driving rotation of the rotation shaft 112a.

On the other hand, the paper S is in a state of being bitten by the guide roller 112 and the feeding roller 113, respectively. Since the paper S travels to be fed into the main body 100 between the feeding rollers 113 which are being rotated continuously, the paper S has a guide roller 112 having one side of the paper S bited therein. It is driven in the same direction as the driving direction. In this case, in the related art, as in FIG. 1, since the guide roller 12 is driven to rotate in response to the traveling of the paper S bited by the feeding roller 13, the pickup roller 11 of the guide roller 12 It is driven by driving and rotated in the same direction as the guide roller 12. Thereafter, the pickup roller 11 had a problem in that jams were generated by picking up to the next sheet S. FIG. However, in the present invention, since the one-way bearing 412 is provided in the guide roller 112, the inner ring portion 212 is in a state of being stopped by the driving interruption of the electromagnetic clutch 124, and thus the pickup roller 111 In addition, since the second gear part 127 is not driven by the first gear part 126, the second gear part 127 is in a stopped state. On the contrary, the pick-up roller 111 because the outer ring portion 312 in the above-described state can be rotated only in one direction, that is, in the same direction as the rotation direction of the inner ring portion 212 along the outer circumference of the inner ring portion 212. Without the influence of the driven rotation, the outer ring portion 312 is driven only by the running of the paper (S) in accordance with the rotation of the feeding roller 113 can feed the paper (S) to the feeding roller 113 Will be.

Thus, unlike the related art, only the outer ring portion 312 of the guide roller 112 is driven in correspondence to the paper S traveling between the feeding rollers 113, so that the pickup rollers 111 are picked up by the guide rollers 112. ) Can be suppressed from following.

As described above, the feeding apparatus of the electrophotographic printing press according to the present invention employs a one-way bearing on the guide roller for feeding the paper to the feeding roller, and unlike the conventional method, the paper feeder feeds the feeding roller. There is an advantage in that the jam can be prevented by suppressing the pick-up roller being driven.

Claims (2)

A pickup roller for pushing out the paper stored in the cassette, and driven by a predetermined driving source to drive the pickup roller in the same direction as the rotation direction of the body, and guide the paper picked up by the pickup roller toward the feeding roller. In the paper feeder of the electrophotographic printing press equipped with a guide roller for The guide roller is provided to cover the inner ring portion rotated by the drive source, and the inner ring portion is provided so that the outer ring portion is rotated together with the body is caught in the inner ring portion when the inner ring is rotated by the drive source, the outer ring portion , And the driving source is interrupted and driven in the same direction as the traveling direction of the paper in response to the running of the paper bitten by the feeding roller. The method of claim 1, And a one-way bearing disposed between the inner ring portion and the outer ring portion.