JPS5983460A - Detector of residual amount of recording paper - Google Patents

Abstract

PURPOSE:To detect less residual amount and shortage of recording paper with one detecting circuit, by taking a mark recording the recording paper as intermediate density and providing a discriminating circuit. CONSTITUTION:A prescribed mark 12 is written in for the length corresponding to at least one recording paper from the rear end of the recording paper 1. The detecting circuit 2 outputting a signal different from the detection of the mark 12 and the shortage of paper is provided. The detected output from the detecting circuit 2 is inputted to a recording paper carrying control circuit 4 via a discriminating circuit 3. The recording paper carrying control circuit 4 stops the carrying of the recording paper when the paper shortage signal is outputted and the recording of one paper during recording is finished after the mark 12 is detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a recording paper remaining amount detection device, and particularly to a recording paper remaining amount detection device for a facsimile machine that uses a roll of recording paper.

[Prior art]

A recording paper remaining amount detection device in a conventional facsimile machine using a roll of recording paper writes a mark at least the length of one record from the end of the roll of recording paper, and inserts the mark into a light emitting diode and an optical transmitter. After continuing to feed out the recording paper until the end of the recording, the feeding of the recording paper is stopped at the end of the recording.

As a result, even if a mark is detected after reception has started and it turns out that the amount of recording paper remaining is low, a complete record will be obtained for the one document currently being received, preventing retransmissions and reducing waste. Communication time can be prevented.

However, in the conventional configuration, when there is little light incident on the optical sensor of the detection circuit, that is, when a mark indicating that the remaining amount of recording paper is low, the detection signal output from the detection circuit and the incident light are completely different. It is not possible to distinguish the signal output from the detection circuit when there is no recording paper, that is, when there is no recording paper.

Therefore, if the recording paper is skewed or torn and the mark is not detected and the recording paper runs out, or even if the mark is detected, the remaining amount of paper cannot be obtained after that. , even after the recording paper has passed through the recording electrode section, the energization of the recording electrode section and the operation of feeding out the recording paper will not continue for a period of time equivalent to the end of recording for one sheet. or cause wasted communication time.

As a countermeasure against this problem, a recording paper out detection means is provided outside the mark detection circuit, and when the recording paper out is detected, recording is stopped and the feeding of the recording paper is stopped.

In other words, the conventional recording paper remaining amount detection device does not include a recording paper out detection circuit in addition to a mark detection circuit, and cannot prevent damage to the recording electrode drive circuit or wasted communication time. There is a drawback.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a recording paper remaining amount detecting device that can prevent damage to recording electrodes or electrode drive circuits or waste communication time by providing - number of detection circuits.

[Structure of the invention]

The recording paper remaining amount detecting device of the present invention includes a roll-shaped recording paper that is fed out sequentially from the leading edge and has a predetermined mark written on at least the length of one recording sheet from the trailing edge, and a detection circuit that outputs a first detection signal and outputs a second detection signal when the absence of the recording paper is detected; and the first detection signal and the second detection signal are set in advance. a discrimination circuit that compares it with a reference voltage and outputs it as a remaining amount reception signal and a recording paper out signal; and a discriminator circuit that outputs a remaining amount reception signal and a recording paper out signal, respectively, and feeding out the recording paper until the end of one recording being received when the remaining amount reception signal is supplied. and a recording paper conveyance control circuit that continues the recording paper conveyance control circuit and stops feeding the recording paper when the recording paper out signal is supplied.

[Explanation of Examples]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, and the recording paper remaining amount detection device shown in FIG. 1 includes a roll of recording paper 1, a light emitting diode 21. Optical sensor 22 and inverting amplifier 23
a detection circuit 2, a discrimination circuit 3, and a flip-flop 41. The recording paper conveyance control circuit 4 includes an AND circuit 42 and an OR circuit 43.

As shown in FIG. 1, a roll of recording paper 1 is held by a spool 11 and is fed out sequentially from the leading end, and the terminal end is attached to the spool 11 and is pulled under a predetermined tension in the feeding direction. It is set to separate from the spool 11 when pulled by force.

On the white back surface of the recording paper 1, an optically readable band-shaped mark 12 having a length of at least one recording run from the end in the recording paper feeding direction is written in advance. The mark 12 is written with an intermediate level or color tone that is about 1/2 of the output voltage when the output voltage from the optical sensor is read by the optical sensor 22;
The writing width is usually 15 to 20 mm, taking into account variations in writing and installation errors of the detection circuit 2.

The light emitting diode 21 and the original sensor 22 of the detection circuit 2 are provided on the recording paper transport path between the spool 11 and a recording electrode section (not shown).

The light from the light emitting diode 21 illuminates the back surface of the recording paper 1, and the reflected light is received by the optical sensor 22.
The output voltage from 2 is inverted and amplified by an inverting amplifier 23 and output as a detection signal A.

−〇 − Here, when the light emitting diode 21 is irradiating the white part of the recording paper 1 (the part without the mark 12), the output %f, f% from the optical sensor 22 is maximum, so the reflection at that time is f
The output voltage from amplifier 23 is set to 11 zero.

When the recording paper 1 is sequentially fed out and the mark 12 is detected by the optical sensor 22, a first detection signal A1 among the detection signals A is outputted from the 5 anti-f amplifier 23.

Further, when the recording paper 1 is fed out, the end of the recording paper 1 is detached from the spool 11 and the light emitting diode 21 and the optical sensor 22
Pass through the detection party strategy formed by.

In this case, the incident light to the optical sensor 22 is not distorted, and the second detection signal A2 in the detection signal A is output from the inverting amplifier 23.
is output.

The voltage ratio between the first detection signal A1 and the second detection signal A is approximately 1:2 for the reason described above.

The detection signal A is supplied to the discrimination circuit 3. In addition, the signal is supplied from the detection terminal A and the terminal T to a display circuit (not shown) to display an alarm indicating that there is no recording paper.

The discrimination circuit 3 uses a preset reference voltage S and a detection signal A.
When the voltage is lower than the reference voltage S, the first detection signal A is generated, and when the voltage S is higher than the reference voltage S, the second detection signal A2 is generated. A corresponding "high" recording paper out signal C2 is output. However, the reference voltage S
is set to about 80% of the voltage value of the recording paper out signal C (at which the output voltage of the inverting amplifier 23 reaches its maximum value), taking into account the fluctuation range of the recording density of the mark 12.

Next, the recording paper conveyance control circuit 4 receives the supplied low remaining amount signal B.
The feeding control of the recording paper 1 is performed in response to the receiving signal C and the recording paper out signal C, respectively.

When the mark 12 is detected by the detection circuit 2 during reception recording,
A “high” remaining amount information signal B is sent from the discrimination circuit 3 to the clock terminal CK of the flip-flop 41 of the recording paper conveyance control circuit 4.
supplied to Ten V volts are supplied to the input terminal of the flip-flop 41, and a "high" low level signal B is output.
is set when the output terminal Q is supplied.
Outputs the signal.

The "high" output signal from flip-flop 41 and 10
The AND circuit 42 calculates the logical product of the receiving signal C of 10-'', and the logical sum of the low output signal of the tea supply and the out-of-recording signal C of 10-'' is performed by the logical sum circuit 43. Then, the OR circuit 43 outputs a "low" stop instruction signal E. Therefore, a "low" stop instruction signal is supplied to a reception control section (not shown), and feeding of the recording paper 1 and energization of the recording electrodes continue.

When one message being received is completed, the receiving signal becomes "high", and the output signal of the AND circuit 42 becomes "high", so the stop instruction signal E from the OR circuit 43 becomes "high".
"High", and feeding of the recording paper 1 and energization to the recording electrodes are stopped.

In this state, the trailing edge of the recording paper 1 does not pass through the detection optical path, so a complete recording can be made.

In other words, regardless of whether or not the mark 12 is detected, the output signal of the AND circuit 42 is "high" or "low".
In any case, when the detection circuit 2 detects that there is no recording paper and the discrimination circuit 3 outputs the "high" 9- no recording paper signal C, the stop instruction signal E from the OR circuit 43 is If "high" is selected, feeding of the recording paper 1 and energization to the recording electrodes are stopped.

3. Figure 2 is also written on the recording sheet, m-2).

This is an example. In the figure, mark 12' is formed by thin black density lines of approximately equal recording width arranged at approximately equal intervals.
When such a mark is detected, the output voltage of the blank sensor 22 becomes 1/2 of the output voltage for white. In FIG. 2, the recording length a of the mark 12' indicates the length of the recording sheet, and the reference numeral 13 indicates the end of the recording paper 1.

Figure 3 shows a third example of marking on the recording paper 1. In the figure, the marks 12'' are black S! degree circles with approximately equal diameters d arranged at approximately equal intervals in a staggered manner. ,
As in the second example, a detection signal equivalent to the halftone density is obtained.

Also, marks 12, 12', 12'' have a writing length a from the end.
Instead of having a length of 10, it is also possible to have a length that starts at a position of the writing length a from the end and can be detected by the detection circuit 2 in the direction of the end.

〔Effect of the invention〕

As described above, according to the present invention, by adding a discrimination circuit and writing a mark corresponding to the intermediate W14 density on the recording paper, it is possible to detect low remaining amount and no recording paper by simply providing - detection circuits. Since it can be detected, the recording electrode or electrode part 111
This has the effect that it is possible to provide a recording paper remaining amount detecting device that can prevent the occurrence of waste in p beats of the circuit or in one hour of passage.

[Brief explanation of the drawing]

Figure 1 is a failure! [] is a schematic configuration diagram showing an example of [ ], FIG. 2 is an explanatory diagram of the second example of the mark in the embodiment shown in FIG. 1, and FIG. 3 is an illustration of the mark in the length example shown in the first factor. The third example is the opening of the country. In the figure, 1...recording paper, 2...detection circuit, 3...discrimination circuit, 4...recording paper conveyance control circuit, 11... ...Spool, 12
, 1.2', 1.2"...Mark, A...
・・Detection signal, B・・・・Sending/small signal, C・・・・
...Record No./Figure

Claims (2)

[Claims] (1) A roll of recording paper that is fed out sequentially from the front end and has a predetermined mark completely written on at least the length of the record from the rear end, and when the mark is detected, outputs a first detection signal, and a detection circuit that outputs a second detection signal when detecting the absence of recording paper; and a detection circuit that compares the first detection signal and the second detection signal with a preset reference voltage for discrimination. a discrimination circuit that outputs a low remaining amount signal and a no-recording paper signal, respectively; and a discrimination circuit that continues feeding out the recording paper until the end of recording of the one being received when the remaining amount low signal is supplied, and when the recording ends. and a recording paper conveyance control circuit that stops feeding out the recording paper when the recording paper out signal is supplied. (2) The recording paper remaining amount detecting device according to claim 1, wherein the mark is written at least at a portion corresponding to one recording from the end of the recording paper.