JPS6063562A - Copying paper carrying device for copying machine - Google Patents

Abstract

PURPOSE:To prevent a copying paper from being broken, and to improve a copying capacity at the time of a both surface copying by constituting so that a speed of a returning belt for inversion becomes faster than a carrying speed of a main machine, immediately after the rear end part of a copying paper whose one surface has been copied has passed through a fixing part. CONSTITUTION:In case of a both surface copying, a copying paper whose one surface has been copied is led in the lower direction by a carrying direction switching plate 27, led into a lead-in roller 29, and supplied to an inverting cassette by a returning belt 33. In that case, this device is constituted so that a speed of the returning belt 33 becomes faster than a carrying speed of a main machine, immediately after the rear end part of the copying paper has passed through a fixing part 25a. According to such a constitution, even in case of a copying paper whose size is larger than a distance between the fixing part 25a and a nip of the lead-in roller 29, it does not occur that the front end part is drawn and broken, and a copying capacity at the time of a both surface copying can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a copy paper conveyance device for a copying machine, and more particularly to a copy paper conveyance device for a copy machine that can copy both sides of copy paper.

Conventionally, the copy paper used to copy materials such as manuscripts has only been copied on one side.
The need for double-sided copying has arisen in order to save copy paper, and because when a large amount of copy paper is consumed, the amount of paper used is halved, making storage of copy paper more efficient.

In order to make double-sided copies, a complicated method is used in which one side of the copy paper is copied, the copy paper is ejected from the output port, the copy paper is manually turned over, and the copy paper is placed in the feed port and copied again. The drawback was that it was inefficient.

In order to eliminate these drawbacks, some large-scale copying machines have been developed that automatically flip the copy paper and make double-sided copying possible, but this requires a complicated flipping mechanism and requires equipment. As a result, it was inconvenient that it could not be adapted to small desktop-type machines.

Therefore, the present invention includes a fixing device 25 that receives the copy paper A supplied from the first paper feed cassette 3 and after an image has been transferred on one side and fixes the image, and a Paper A is transferred to the copy tray 5 based on the command signal.
A conveyance direction switching plate 27 that conveys the conveyance to either one of a first guide path leading to the first guide path and a second guide path branching from the first guide path; The above paper is placed on the return belt 33 that pulls in the copy paper A that has been sent in the direction of Pull-in rollers 29 and 29' that pull in the copy paper A
and the feeding speed of the return belt 33 is equal to or greater than the copy paper A.
Copy paper for a copying machine configured such that as soon as the trailing edge passes through the printing section 25a of the fixing device 25, the copy paper feeding speed on the conveyance path before reaching the return belt 33 becomes faster. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a simplified cross-sectional view of the copying machine in an inverted state, and FIG. 2 is a cross-sectional view of the copying machine that makes copies on the other side of the inverted state. In the figure, reference numeral 1 denotes a main machine frame, and a transparent plate 2 on which a document is placed horizontally is provided above the frame. Copy paper A
As shown in FIG. 1, the first paper feed cassette 3, which stores the The paper feed cassette 3 is placed below the first paper feed cassette 3.
The copy tray 5 is discharged onto the copy tray 5 provided at the left end in the figure. Note that the paper feed cassettes installed in the main machine frame 1 in this way are the first paper feed cassette 3, the second paper feed cassette, which are installed vertically side by side.
The number of paper feed cassettes 4 is not limited to two in two stages, but a large number of paper feed cassettes 4 may be arranged vertically in multiple stages, such as three in three stages, to store copy sheets of various sizes.

A photosensitive drum 6 whose entire circumferential surface is coated with a photosensitive layer (not shown) is rotatably mounted approximately at the center of the main machine frame 1. The emitted light is projected onto the photosensitive layer through the movable reflecting mirrors 7, 8° in-mirror lens 92 and the reflecting mirror 10 to form an image of the document, thereby forming an electrostatic image on the photosensitive layer. Around the photosensitive drum 6, there is a developing device 12 that develops the electrostatic latent image formed on the photosensitive layer into a toner image, and a cleaning device 14 that removes toner remaining on the photosensitive layer after transfer. and are arranged.

18.18', 20.20', 22.22', 23.2
Reference numeral 3' designates a pair of transport rollers for transporting the copy paper A that has been pushed up by the lever 16 and fed by the paper feed roller 15 for single-sided copying.

In addition, 1 7 and 17' are the paper feed roller 15 and the conveyance roller 1.
19.19 on the guide plate provided between 818'
Reference numerals '21, 21', 24, and 24' denote a pair of guide plates, respectively, which are installed between the rollers and guide the copy paper between the rollers. Reference numeral 25 denotes a fixing device, and the copy paper heat-fixed here is sent out by feed rollers 26 and 26', passes through discharge rollers 44 and 44', and goes to the copy tray 5 through a first guide path, and this first guide path. The paper is conveyed along a second guide path that branches off in the vertical direction and heads toward the return belt 33.

This conveyance method will be explained with reference to FIG. 3. A conveyance direction switching plate 27 is provided between the feed rollers 26, 26' and the discharge rollers 44, 44'.

This conveyance direction switching plate 27 is pivoted by a pivot shaft 27a, and can be rotated about the pivot shaft 27a as shown by the solid line and the imaginary line in response to a command signal, and can be rotated in the horizontal direction as shown by the imaginary line. When the copy paper is sent out from the delivery rollers 26 and 26', it passes through the conveyance direction switching plate 27, passes through the discharge rollers 44 and 44', and takes the first guide path toward the copy tray 5. On the other hand, when the conveyance direction switching plate 27 rotates upward as shown by the solid line, that is, when the oblique side portion 27b rotates in the direction facing the feed rollers 26 and 26', the copy paper fed out from the feed rollers 26 and 26' takes a second guide path that comes into contact with the conveyance direction switching plate 27 and branches in the vertical direction.

Below this conveyance direction switching plate 27 is a lead-in port 29.
, 29' are disposed and contact the conveyance direction switching plate 27 to pull in the single-sided copy paper that has been branched from the horizontal direction to the vertical direction. Place copy paper on top. Also 2
8.28' (FIG. 1) is a guide plate that guides the copy paper branched from the conveyance direction switching plate 27 to the return belt 33.

As shown in FIG. 1, this return route 33 is connected to an idle roller 31 disposed at the left end of the auxiliary machine frame 30 that is integrally attached to the main machine frame 1, and an idle roller 31 disposed at its right end. (Strung between the seat rollers 32.The return belt 33 is not limited to a belt, and a roller conveyor may also be used.In short, any belt on which the copy paper can be placed and transported can be used. Then, the feeding speed of the return belt 33 is such that as soon as the trailing edge of the copy paper A passes the fixing section 25a of the fixing device 25, the return speed is set so that the copy paper feed on the conveyance path before reaching the route 33 is controlled. It is configured to be greater than the speed.

A belt roller 34 is disposed on the belt roller 32 with a return belt 33 sandwiched therebetween, and a belt roller 35 is provided diagonally above the belt roller 34 to protrude from the main machine frame 1. A belt roller 37 is provided to sandwich the auxiliary belt 38, and an auxiliary belt 36 is provided between the belt roller 34 and the belt roller 35, and an auxiliary belt 38 is provided between the belt roller 32 and the belt roller 37. The copy paper is conveyed by the return belt 33 and is held between the auxiliary belts 36 and 38 and fed to the guide plates 39 and 39'. Information board 39
, 39' are attached to the second paper feed cassette 4, and a pair of reversing rollers 40, 40' are provided at one end thereof. These reversing rollers 40 and 40' are connected to the guide plate 39.
, 39' rotates four times (hereinafter referred to as reverse rotation) so as to feed the copy paper guided by 39' into the second paper feed cassette 4.
or in a direction away from the second cassette 4 (hereinafter referred to as normal rotation).

To explain double-sided copying of copy paper using the copy paper conveyance device for a copying machine having the above configuration, as shown in FIG. The second paper feed cassette 4 is an empty cassette in which the copy paper A that has not been fully heated is stored. In this state, the copy paper A stored in the first paper feed cassette 3 and pushed up by the lever 16 is transferred to the paper feed roller 1.
5 to feed paper from the paper feed cassette 3. The fed copy paper is transferred to a pair of guide plates 17 and 17', conveyance rollers 18 and 18', guide plates 19 and 19', and conveyance roller 2.
0, 20', guide plates 21, 21', and a pair of conveyor rollers 22, 2i to transfer the corona discharger 13.
The photosensitive drum 6 is fed in close contact with the photosensitive layer of the photosensitive drum 6 facing the photosensitive drum 6 and is transferred. After the transfer is completed, the copy paper is placed on the guide board 24.
, '24' to the fixing device 25 where it is fixed.

The fixed copy paper passes through feed rollers 26 and 26' and comes into contact with a conveyance direction switching plate 27. This conveyance direction switching plate 2
As shown by the solid line in FIGS. 1 and 3, the roller 26 is moved upward, that is, from the oblique side, with the pivot shaft 27a as the center 8- by a command signal in advance.
Since the copy paper is rotated in the direction opposite to the feed rollers 26 and 26', the copy paper fed out horizontally from the feed rollers 26 and 26' is
The guide plate 28 comes into contact with the conveyance direction switching plate 27 and is guided vertically downward as shown in the imaginary line in FIG. .28' guided by a retraction roller 29;
The copy paper is placed on the return belt 33 by the rotation of 29', and at this stage the copy paper is reversed so that the image is transferred to the other side.

That is, one side on which the image has been printed is in contact with the return belt 33, and the other side, which has not yet been copied, is exposed. The copy paper placed on the return belt 33 is conveyed to the right by the movement of the return belt 33 as shown in FIG.
38, guided by guide plates 39 and 39' attached to the second paper feed cassette 4, and led to a pair of reversing rollers 40 and 40'.

By the forward rotation of the pair of reversing rollers 40, 40', the leading edge of the copy paper is projected from the reversing rollers 40, 40'10-, and the rear end thereof is at the end.
At this stage, the reversing rollers 40° and 40' are reversely rotated by a command signal, and the copy paper is fed into the second paper feed cassette 4 with the uncopied side facing up.

Next, in order to copy this last uncopied side, the conveying direction switching plate 27 is rotated about the pivot shaft 27a in parallel to the conveying direction of the copy paper in response to a command signal. That is, the second
It is displaced to the position shown by the solid line in the figure and the imaginary line in FIG. Then there's the liver.

The copy paper pushed upward by the paper feed roller 42 is fed from the second paper feed cassette 4 by the paper feed roller 41. The fed copy paper is guided by guide plates 43, 43' and led to conveyance rollers 20, 20', where it is transferred and fixed via the thread path described above, and is then transferred to delivery rollers 26, 2.
6', the first sheet passes over the conveying direction switching plate 27 as shown by the imaginary line in FIG. It is fed into the copy tray 5 along the guide path. In this way, duplex copying of the copy paper is completed.

By the way, during double-sided copying work, especially in order to copy the other side of the copy paper after the image has been transferred to one side and reversed, it is necessary to move the return belt 33 from the left end to the right end of the auxiliary machine frame 30. It is necessary to move to supply the copy paper to the second paper feed cassette 4, and it is inevitable that it takes time to move this moving distance. Therefore, the feed speed V of the return belt 33 is set as an arrow from the transport speed of the copy paper in the main machine frame 1 so that the copy paper is transported from the left end of the auxiliary machine frame 30 to the second cassette 4 in a short time. By doing so, the copying capacity can be increased.

Therefore, as shown in FIG. 3, it is sufficient to increase the feed speed V of the return belt 33 to a certain extent. When the feeding speed V of the return belt 33 is increased, the drawing rollers 29 and 29' that pull the copy paper into the return belt 33
The rotational speed of the belt must be increased in accordance with the speed of the return belt feed 33. In this case, the copy paper cannot be transferred to the return belt 33 unless the pull-in rollers 29 and 29' are rotated at a speed corresponding to the feed speed of the return belt 33.

However, the length of the copy paper in the conveyance direction may be longer than the distance between the fixing section 25a of the fixing device 25 and the pull-in rollers 29, 29'. Therefore, when the copy paper is conveyed along a thread path like an imaginary line, the front end of the copy paper is held between the drawing rollers 29 and 2, and the rear end is held by the fixing roller 25b of the fixing unit 25a of the fixing device 25. , 25b'. On the other hand, the retraction roller 29,
Since the rotation of the fixing rollers 29' is faster than the rotation of the fixing rollers 25b and 25b', the leading edge of the copy paper is pulled, resulting in the copy paper being torn.

In order to prevent this copy paper from breaking, it is necessary that the trailing edge of the copy paper
Immediately after passing b', the feeding speed of the return belt 33 may be configured to be greater than the copy paper feeding speed on the conveyance path before reaching the return belt 33. With this configuration, the copy paper can be quickly conveyed by the return belt 33 without being broken in the middle of the conveyance thread path, and the return belt 33 is not always rotated quickly; Since the paper is rotated quickly only when it is transferred to the return belt, less power is consumed.

As detailed above, since the present invention has the above configuration, double-sided copying of copy paper, which was difficult in the past, is possible with a simple configuration, and as a result, copy paper can be saved and storage is efficient. became.

In addition, the feed speed of the return belt is configured so that as soon as the trailing edge of the copy paper passes the fixing section of the fixing device, it becomes faster than the feed speed of the copy paper on the conveyance path before reaching the return belt. The copy paper is quickly conveyed by the return belt without being broken on the conveyance thread path, and the copying capacity can be increased.

Furthermore, the return belt is not always rotated at a high speed, but is rotated quickly only when the copy paper is transferred to the return belt, which has the advantage of reducing power consumption.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a simplified cross-sectional view of a copying machine in an inverted state, and FIG. 2 is a state in which it is inverted and the other side on which no image is transferred is being copied. FIG. 3 is a simplified cross-sectional view of the copying machine shown in FIG. 3...First paper feed cassette 4...Second paper feed cassette 5...Copy tray 25...Fixer 33...Return belt A...Copy paper. Patent applicant: Sanda Kogyo Co., Ltd. Representative Patent attorney: Junya Suzuki

Claims (1)

[Claims] A fixing device receives the copy paper A supplied from the first paper feed cassette 3 and after the image has been transferred on one side, and fixes the image. a conveyance direction switching plate 27 for conveying to either a first guide path toward the copy tray 5 or a second guide path branching from the first guide path; 27 to pull in the copy paper A fed in the second direction and return the copy paper A toward the second paper feed cassette 4 installed to transfer the image to the other side. The return belt 33 includes pull-in rollers 29 and 29' for feeding the copy paper A onto the belt 33.
The feeding speed is configured such that as soon as the trailing edge of the copy paper A passes through the fixing section 25a of the fixing device 25, it becomes faster than the copy paper feed speed on the conveyance path before reaching the return belt 33. Copy paper conveyance device for copying machines.