JPS60112551A - Paper carrying system for copier - Google Patents

Abstract

PURPOSE:To prevent collision of paper while to improve the paper feeding speed by temporarily stopping the copy paper sheet to be fed continuously at the fixed position while starting again with reference to said position. CONSTITUTION:A sensor SS for detecting the leading edge of copy paper is arranged between retard roller 8 and takeaway roller 9 in paper carrying system, to stop the copy paper temporarily on the basis of detected signal and to employ said stopping position as the starting point of copy paper. Since the fluctuation of interval of paper until stoppage of paper can be absorbed, collision of paper can be prevented. While since the interval of paper can be shortened as much as possible within detection limit of sensor SS, copy paper feeding speed can be further improved.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a paper conveyance device for a copying machine, and particularly to a paper conveyance device for a copying machine, and in particular, a paper conveyance device for conveying a sheet of copy paper from a paper feed table to a photoreceptor at a predetermined timing. This invention relates to improvements in conveyance devices.

[Prior art]

FIG. 1 is a conceptual diagram showing a conventional paper conveyance device 1, in which sheet-shaped copy paper 3 accommodated in a paper feed table 2 is guided along a paper conveyance path 4 shown by a dashed line, and is transferred to a register storage w''.
The registration gate 5 opens and closes the paper conveyance path at a predetermined timing in accordance with the transfer speed of the photoreceptor 6, and transfers the copy paper 3 to the photoreceptor 6 at an appropriate timing. On the other hand, in the paper transport path 4 leading to the registration date 5, there are a roller drawer () 8, a tie roller 9, and a transport roller 10.11. These rollers move the copy paper 3 through the paper transport path 4 and transport it to the registration gate 5. In FIG. Retard roller 8
This is Feedrow 2 to be sent to

By the way, each of the above-mentioned rows 2 is set at the feed roller 12f position, and the sheet-like copy paper 3 is moved one by one within the paper conveyance path 4 at a predetermined interval according to the opening/closing timing of the registration tray 5. Therefore, each of these rollers is connected to a sensor So
The operation of each is controlled by S1. That is, the sensor 8o detects the copy paper 3 moving between the Tiquaranney roller 9 and the transport roller 10.
The tip of the paper is detected, and the paper conveyance speed of the Tiqualani roller 9 is switched (from high speed to low speed) based on the detection signal of. In addition, this Tiquaranee Roller 9 is
Based on the SQ detection signal, the paper conveyance speed is changed to two speeds, high speed and low speed, through a clutch mechanism (not shown).

Further, the sensor S1 disposed between the trans cheat roller 10 and the transport roller 11 is connected to the roller to,
The leading edge of the copy paper 3 conveyed during the interval tt is detected, and based on this detection signal, the distance between the trailing edge of the copy paper 3 conveyed previously and the leading edge of the copy paper 3 conveyed next, that is, the paper The interval is detected, and if the interval is smaller than a predetermined value, the transport roller 1o and the feed and retard rollers 12, 8 are stopped for a predetermined period of time to prevent collision of sheets. Note that the sensors So and S mentioned above.

Each of them is composed of a photo sensor, a micro switch, or the like.

By the way, in the paper conveyance device 1 described above, when the conveyance speed of the copy paper 3 is increased in order to increase the number of copies per unit time, the paper interval becomes narrower. The sensor So+S1 for determining the transport timing has a detection limit and requires a certain interval. Therefore, when conveying the copy paper 3, the interval between the sheets is usually narrowed to the maximum within the detection limits of the sensors S6+S1 in order to increase the number of copies. However, if the copy paper 3 is fed double to the retard draw 28 due to a feed error by the feed roller 12, the first copy paper 3 is fed from the paper feed table 2, and the second copy paper R3 is fed from the retard roller 8. (The distance between the feed roller 12 and the retard roller 8 is usually 30 mrn to 40 mrn.) In this case, the distance between the first and second sheets becomes extremely close, and the sensor S1 As a result, it is not possible to take appropriate timing for conveying the copy paper 3, and adjacent copy paper sheets collide with each other, causing a paper jam.

/C”? Fig. 2 is a time chart showing the positional relationship between the leading edge and the trailing edge at each point of the copying paper that makes four beats of phase K in the conventional apparatus 1 mentioned above.
v! ;! 21 tThe tip of the preceding copy paper ☆;
1 and the rear wheel, and a solid line 22 indicates the ideal leading edge position of the following copy sheet. In addition, sensor 5 in this case
IK3? The paper spacing is shown between AB in the drawing.

However, when the following copy sheets are fed in duplicate and the leading edge starts from the retard roller 8 shown by the dotted line 23, the sheet interval at sensor S becomes AC, and the sheet interval becomes narrower and becomes outside the detection limit of sensor S. .

[Purpose of the invention]

In view of the above-mentioned problems of the conventional apparatus, the present invention absorbs the variation when copy sheets are fed in duplicate and causes variations in paper spacing, so that copy sheets can be printed within the paper spacing that can be detected by a sensor at all times. An object of the present invention is to provide a paper conveyance device for a copying machine that can convey paper.

[Structure of the invention]

In order to achieve this object, the present invention disposes a sensor that detects the leading edge of copy paper between the paper conveying device's tart roller and Tiqualani roller, and temporarily stops the copy paper based on a detection signal from this sensor. , this stopping position is used as the starting point for copying paper.

〔Example〕

FIG. 3 is a conceptual diagram showing a paper conveyance device 3o according to the present invention, and the same parts as in FIG. 1 are designated by the same symbols.

In this paper conveyance device 3o, a sensor ss for detecting the leading edge of the copy paper 3 is arranged in the paper conveyance path 4 between the retard roller 8 and the Tiquala Aero-29. Note that the sensor SS is composed of a photo sensor, a micro switch, or the like. This sensor SS is connected to the paper conveyance path 4 between the retard roller 8 and the takeaway roller 9.
Detects the leading edge of copy paper 3 sent to 9:l]
Based on the signal, the feed roller 12 and the retard zero roller 8 are temporarily moved to stop the copy paper 3 at that position.

Thereafter, the four sheets 3 before copying, which have been stopped, are output from the feed row 212 and the tart roller 8, which operates at the opening/closing timing of the first injection case 5, using the stop position as the starting position. Hunting transport route 4
sent within. As a result, as shown in FIG. 4, in which the same parts as in FIG. Since it is started again at the timing of , the variation in paper spacing that occurs between the feed roller 12 and the retard roller 8 is absorbed there, and from then on, the graph 22 of the subsequent copy paper is adjusted to the ideal paper spacing. It will move along. Therefore, the trailing edge of the forward copying paper (graph 21 indicated by a dashed line) and the leading edge of the following copying paper (
By keeping the sheet spacing EFi at sensor S1 constant with respect to the graph 22) shown by the solid line, it is possible to always set the sheet spacing between copy sheets within the detection limit of sensor S1.

[Effects of the Invention] According to the present invention, the sheet-like copy paper that is continuously conveyed is temporarily stopped at a fixed position, and then restarted based on that point. Therefore, it is possible to eliminate cases where the paper spacing becomes extremely close to the sensor's detection limit, and compensate for subsequent variations in the paper spacing using the sensor, thereby preventing paper collisions. At the same time, since the paper interval can be narrowed as much as possible within the detection limit of the sensor, the paper feeding speed of the copy paper can be further improved.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing a conventional paper conveying device, FIG. 2 is a time chart showing the relationship between the position of copy paper and time in the conventional device, and FIG. 3 is a conceptual diagram showing a paper conveying device of the present invention. FIG. 4 is a time chart showing the relationship between the position of copy paper and time in the paper conveyance device of the present invention. 3... Copy paper, 4... Paper transport path, 6... Photoreceptor, 8... Retard roller, 9... Tikuala Aero-2, ss... Sensor. Figure 1 Figure 2

Claims (1)

[Claims] In a paper conveyance device of a copying machine that continuously conveys a sheet of copy paper to a photoreceptor at a predetermined timing via a retard roller and a Tiqualani roller, there is a A sensor is placed in the paper transport path to detect the leading edge of copy paper.
Based on the detection signal of this sensor, the copy paper is temporarily stopped in the paper conveyance path between the retard roller and the Tiqualani roller, and then the copy paper is conveyed again using the stopped position as a starting position. A paper conveyance device for a copying machine characterized by: