JPS58193848A - Skew discrimination system - Google Patents

Abstract

PURPOSE:To realize utilization of the captioned system for a duplicator and printers which handle cut sheet by enabling a skew to be set on the basis of allowance range variable correspondingly to kinds and use of a form and excluding loss of a part of recorded data or waste of forms. CONSTITUTION:Before a form is detected by means of microswitches 1, 2, a flip- flop 5 is reset and a binary number (m) is preset in a counter 8. From the time the form is detected by either one of the switches 1, 2 until it is detected by both of them, the counter 8 counts up and, in case the skew is fairly large, the counter 8 becomes overflowing and a carrier signal is given from a carrier output terminal 9, thereby skew out is detected. In case a skew is fairly small, the flip-flop 5 is reset before the counter 8 becomes overflowing and the counter 8 stops counting. Further, when the form passes through the microswitches 1, 2, no output is given from the terminal 9 because the binary number of the next form is preset.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a ski-judgment method that can vary the ski-permissible range depending on the type of paper used or its purpose.
It can be applied to paper control in copying machines.

(Seikan technology) In Figure 1, +l is the conventional ski-detection method, and paper running /
, time I), the paper detection element A, 11 is provided in a curved direction, and the time difference between the leading edge of the paper traveling and coming through A and I (is 1 or more as shown in FIG. 1(b)). and paper running failure and 1-skew out.However,
The ski tolerance range is determined by a fixed value T regardless of the size and purpose of the monthly paper, so the tolerance standards may be too loose or too strict, resulting in some data not being recorded or vice versa. I often ended up skewing out items that were still useful even when I skied them, wasting paper.

(Problem to be solved by the invention) The present invention is characterized by being able to change and set the permissible range of skiing depending on the paper type and usage.The purpose of this invention is to This will be explained in detail below.

(Structure and operation of the invention) FIG. 2 shows an embodiment of the present invention, and 1 and 2 are microsinches that detect the running of paper, and are arranged in a line in a direction perpendicular to the paper running direction. If detected, the contact closes. 3 is a N0I-t gate, and when both microswitches 1 and 2 are closed, an output 1-1 is output and a flip-flop 5 is set. 4 is an AND gate, which outputs when both microswitches 1 and 2 are open.
1" is output, the flip-flop 5 is reset, and at the same time, "l" is sent to the load terminal 0 of the counter 8, and the binary number m supplied to the preload terminal 12 of the counter 8 is loaded into the counter 8. 5 is a flip-flop whose Q output is input to the count up terminal 11 of the counter 8, and while the load signal is not coming and the Q output is "
1", the counter 8 is counted up. 6 is a switch that can be selected depending on the paper type and usage, and preloads the binary number m (m varies depending on the paper type and usage) to the preload terminal of the counter 8 via the encoder 7.
C-kill.

FIG. 3 shows a time chart during paper travel. 1゜2, /
The numbers 1, 5.8 correspond to the numbers in FIG. 2, and the low level "1" of the switch 1.2 corresponds to no paper detection, and the low level "0" corresponds to paper detection.

Paper is detected by microswitches 1 and 2.Ail
, the flip-flop 5 is reset, and the counter 8 is preset with a binary number m (P is preload,
Q indicates a count amplifier, R indicates a count stop). During the period from when paper is detected by either switch 1 or 2 until it is detected by both switches, the counter 8 counts up and there is a sufficient skew (...), the counter 8 overflows, and the carrier output terminal 9 A carrier signal is emitted from the

This allows skew-out to be detected. If the key is sufficiently small, the flip-flop 5 is reset before the counter 8 overflows, and the counter 8 stops counting. Furthermore, when the paper passes through the microswitches 1 and 2, the binary number of the next paper is preset. , no carrier signal is output from the carrier output terminal 9. Also 2
By making the base number 1n thicker, even a slight skew can result in skew-out.On the other hand, if m is made small, even a large skew will not result in skew-out.In this way, the paper size or purpose By selectively preloading the binary number Ill into the counter according to The switch 3, which is selected depending on the paper size and purpose, may be replaced with a signal from a control device (not shown).Furthermore, a microcomputer and memory may be used, and the memory It is possible to perform a similar operation by using +11 as a part of the counter. For example, when two paper detectors both detect no paper, the set W value is stored in the random access memory (below) ( , AM) is stored in (-1) When one of the paper detectors detects the presence of paper, the value stored in the rtAM is incremented by 1" at regular intervals, and if two paper sheets are detected. If the value stored in I(, AM) reaches a predetermined value by the time both A and A detect the presence of paper, some
It may also be possible to send a signal representing the .

Also, for example, the setting value is stored at the first address of RAM (-12
When both paper detectors detect paper out or paper presence, the second address of RAM is set to the value "0"' (-j, i.e. clear), and one of the paper detectors detects paper presence. While doing so, the second address of the RAM is incremented at regular intervals, and the contents of the first address and the second address are compared,
When the content at the second address becomes thicker than the content at the first address, a signal indicating the skew may be sent from the microcomputer.

Also, without directly comparing the counted value and the set value, for example, if the counted value +
(Effects of the Invention) As explained above, since the permissible range can be changed depending on the size of the paper and the purpose, it is possible to use a copying machine that handles many cut sheets. , can be used for printers.

[Brief explanation of drawings]

1(a) is a conventional skew detection circuit, FIG. 1(b) is an operation time chart of the device in FIG. 1(al), FIG. 2 is a circuit diagram of an embodiment of the present invention, and FIG. 3 explains FIG. This is an operation time chart. 1.2... Microsinch, 3... NOH gate, 4... AN+) gate, 5... Flip-flop, 6... Switch,
7...Encoder, 8...Counter, 9...
...Carrier output terminal, 10...Load terminal, 11.
...Count up terminal, 12...Preload terminal. Patent applicant Oki Electric Industry Co., Ltd. Patent application agent Patent attorney Megumi Yamamoto -i/(d) 8

Claims (1)

[Claims] +11 When two paper detectors are arranged in a direction perpendicular to the running direction of the cut sheet, and the time difference between paper detection outputs from the paper detectors becomes longer than a set time. In the skew determination method that determines skew, one type of setting time is selected from a plurality of predetermined setting times (digital).
HF of the counting means; a setting means for outputting the time difference as a digital value;
A ski characterized in that the number capacity is set by the setting means; and the allowable amount is set by the set time.
Judgment method. (2) The counting means is a digital counter that is incremented by a clock pulse, the initial value of which is set by the set time, and an overflow of the counter determines that the set time has been exceeded. Skiing described - Judgment method.