JPS5978051A - Paper transport detector - Google Patents

Abstract

PURPOSE:To heighten the reliability by detecting a mark put on a specified paper of a set of plural copy papers such as a statement of delivery used in a department store or the like with a processing order sensor, thereby detecting a slippage such as skewing to mask an abnormal output. CONSTITUTION:A transport path 5 for a copy paper is provided with a paper feed tray 1, paper feed rollers 2, transport rollers 3, register rollers 4, a photosensitive drum 6 and a group of sensors 7. The group of sensors 7 comprises sensors 7a, 7b for a slippage of a specified paper 8, a sensor 7c for paper passing, and a processing order sensor 7d for detecting a mark 9. A control circuit comprises inverters I1-I4, an AND gate A1, a NAND gate NA1, an OR gate OR1, a multi-feed detecting circuit 10, a R-S flip-flop 11, and an LED12. Where the specified paper 8 on which the mark 9 is put is not detected by the processing order sensor 7d, an abnormal signal is output, and where the specified paper 8 is slipped out of a normal transport position and the mark 9 does not pass above the sensor 7a, an abnormal output is masked in response to outputs of the sensors 7a, 7b.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a paper conveyance detection device for a copying machine, etc., and more specifically, for detecting paper conveyance in a copy paper, such as a set of multiple bound slips. This relates to the space between paper conveyance detection devices.

BACKGROUND TECHNOLOGY In general, delivery slips and honorable mention slips used in shops, department stores, etc. consist of one for submission to the recipient, one for pasting products, one for copies, and others, and are often made up of 5 to 7 sheets per set. .

When copying a large number of original documents with product names, customers, addresses, etc. written on such documents, the documents are fed into the paper transport path inside the copying machine, but in this case,
When vertical feeding occurs, not only the required number of sheets in one set is missing, but also the order of conveyance is disrupted, resulting in a shift in the desired copy content, causing a significant inconvenience.

Many vehicle transport detection devices have been proposed in the past, but some have extremely thin paper or extremely high transparency.
It was difficult to say that the reliability for low-quality products was completely satisfactory.

Purpose The present invention uses a predetermined number of sheets of copy paper as a specific paper, and detects marks such as patterns or holes provided on the specific paper at a predetermined timing using a processing order sensor (conveyance order sensor). In addition to detecting yellowing in the processing order, if a mark cannot be detected due to a shift in the conveyance position such as skewed feeding, the abnormal signal output can be masked to increase reliability. The purpose is to

Ikkanaba blockade The structure of the present invention will be explained in detail based on the following examples.

FIG. 1 is an explanatory diagram showing a double feeding path for copy paper.

In the figure, 1 is a paper feed tray, 2 is a paper feed roller, 3 is a transport roller, 4 is a registration roller, and the arrow indicates a transport path 5. 6 is a photosensitive drum.

A sensor group 7 is provided in such a conveyance path 5.

FIG. 2 is a first explanatory diagram showing a system between the sensor group and copy paper positions.

The sensor group 7 includes F double feed position deviation sensors 7a and 7b for detecting misalignment of the conveyance position of the copy paper (specific paper) 8, a paper passing sensor 7C1 for detecting whether the copy paper is being conveyed, and a paper feed sensor 7C1 provided on the specific paper 8. Processing order sensor 7d that detects mark 9
It consists of Further, an arrow +-1 indicates the traveling direction of the copy paper 8.

Shifting of the conveyance position refers to a shift in paper position in a direction substantially perpendicular to the direction of travel or a shift in position in an oblique direction (this case is called diagonal feeding or skew). Furthermore, when the specific paper 8 is transported normally, the processing order sensor 7d reads the presence or absence of the mark 9 at the timing when the mark 9 passes over it, and detects whether or not the transport is abnormal. These sensor groups 7 are composed of reflective optical sensors.

Further, the conveyance position shift sensors 7a and 7b are provided outward and inward at a distance of l, perpendicular to the direction of movement, with respect to the normal position. On the other hand, the mark 9 has a width of 21 in the direction perpendicular to the direction of travel, and its center position passes over the car processing order sensor 7d.

Note that the mark 9 may be a turn drawn on the specific paper 9 or may be a through hole.

FIG. 3 is a block diagram of a control circuit according to an embodiment of the present invention.

In the figure, ■, ~■4 are inverters, AI is an AND gate, NA is a Nant gate, OI is an OR gate,
10 is a double feed detection circuit, 11 is I? , S flip-flop, 12 is J, E +). Each of these circuits is connected as shown in the figure, and the waveforms of each part are indicated by a-k.

LID I) 12 indicates a feeding abnormality when the conveyance order of copy paper is out of order due to double feeding.

Note that a is the output of the paper passing sensor 7C, and b is the single feed position fi'ff.
i is the output of the shift sensor 7a, C is the output of the shift sensor 7b, and j is the output of the processing order sensor 7d.

The construction of this circuit will be explained based on the timing chart of 3 to 5 shown in FIG.

First, every time copy paper is conveyed, this is the paper passing sensor 7C.
Therefore, the C output outputs a pulse every time copy paper is conveyed. By the way, the second pulse P2 is in the order 1~
If the misalignment is caused by the copy paper (if the misalignment is upward-outward in FIG. 2), the conveyance position shift sensor 7a detects this. Therefore, the pulse P at aVC
The pulse P1 at b will be output within a time of 2. The reason why the rises are not synchronized here is because
Indicates that copy paper is being fed diagonally. The output of b is inverted by the inverter 2, and a low level input is made to one of N and A.

Therefore, a high level output is made from this NAND game (NA) regardless of other inputs. This is the C output. b
The output pulse P, and the C output pulse P.

Synchronize with. C output is)1. - It is input to the cent terminal of the S flip-flop 11, so that the output of the 1C S7 flip-flop 119Q becomes a no-low level.

This output continues until the start of the next paper feed.

That is, when the pulse P3 at the a output is output, it is rotated twice by the inverter 2.13 and input to the positive terminal of the -8 flip-flop 11. By the way, when the f output (Q output of a flip-flop) occurs as P, the sub-output g output becomes F.

It will be like this. This enters one input terminal of AND gate A, and becomes a mask output, which will be described later.

On the other hand, the j output (output from the processing IQ41i1it order sensor 7d) and the a output (output from the paper passing sensor 7c) enter the double feed detection circuit 10, and as described above, a conveyance error is detected depending on whether mark 9 is detected at a predetermined timing. Determine whether it is normal or not.
If there is an abnormality, it outputs h output. However, P.

Since the above-mentioned mask output is not output at the abnormal output timing, a non-mask abnormal signal is output from the AND gate AI. However, at the timing of P, there is a g output P, and this g output causes h in the AND gate A.
Since the output is masked, no abnormal signal will be output.

When the third sheet of paper is fed and a failure P3 output is output in the a output, this time, this copy paper is positioned on the inside and the C output (output of the single-feed position deviation sensor 7b) is output from the middle. °na(
If it becomes (Ps at C output) OR
, the output d falls to a low level. Then, the C output, which is the output of the Nant gate NA, becomes high level, and the f output (C output of the flip-flop 11) becomes high level, indicated by P, as described above. Thereafter, in the same manner as described above, even if an abnormal signal output (h output) is generated within the timing of the g output (C output of the flip-flop 11), this is masked.

Effects As described above, the present invention detects a conveyance abnormality due to double feeding by detecting a specific sheet of copy paper at a predetermined timing among the copy sheets whose processing order is determined, and also detects a conveyance abnormality due to a conveyance position shift when the specified paper reaches the predetermined number of copies. This device is designed to prevent malfunctions by masking the abnormal signal output when the mark set on the sensor cannot be detected even though the sensor is in the correct position, making it an extremely reliable device. I can do it.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the copy paper conveyance path, Fig. 2 is an explanatory diagram showing the relationship between the copy paper and the sensor group, Fig. 3 is a control circuit block diagram of one embodiment, and Fig. 4 is an explanatory diagram showing the relationship between the copy paper and the sensor group. It is a timing chart of each part of a block diagram. 7a, 7b...Transportation position deviation sensor, 7d
...Processing order sensor, 8...Specific paper,
9...Mark.

Claims (1)

[Claims] One of the sheets arranged in a set of at least two sheets arranged in the processing order is designated as a specific paper with a mark, and when the processing order sensor does not detect this mark at a predetermined timing, the processing is stopped. In addition to outputting an abnormality signal to detect an abnormality in the order, if the mark does not pass over the processing order sensor due to the specific paper being deviated from the normal conveyance position, the output of the conveyance position f4 deviation sensor detects the abnormality. A paper conveyance detection device characterized by masking signal output.