JPH04266350A - Medium detection circuit - Google Patents

Abstract

PURPOSE:To flexibly respond to the change in a detection condition when it is not detected by a comparative detection means whether there is a medium or not, by carrying out detection in order through the comparative detection means under a detection condition changed by a detection condition changing means, so as to stably carry out the detection of the medium. CONSTITUTION:When a medium passes through the point of a sensor 4, the information of the sensor 4 and a predetermined detection condition of the sensor 4 set by a detection condition setting part 2 are compared to one another in order by a sensor detection part 3, and when the comparison results are identical, it is informed to a sensor sense control part 1 that there is the medium detected. When the comparison results are not identical, it is informed to the detection condition setting part 2 that there is no medium detected, and the detection condition is changed by the detection condition setting part 2, while the information from the sensor 4 is compared by the sensor detection part 3 under the changed detection condition, so as to detect whether there is the medium or not. When the medium is not detected, the detection condition is changed in order by the detection condition setting part 2, and the detection of the medium is thus proceeded, and when the medium is not detected as a result, it is determined that there is no medium.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detection circuit that detects the presence or absence of a medium using a sensor, and more particularly to a medium detection circuit that detects a medium by changing detection conditions.

0002

2. Description of the Related Art Conventionally, a medium detection circuit using a sensor of this type is a detection circuit that detects the presence or absence of a medium by fixing medium detection conditions and detecting a change point in the output of the sensor.

0003

As described above, in the conventional medium detection circuit, the medium detection conditions are fixed in terms of hardware, so there is a drawback that it cannot respond flexibly to changes in the detection conditions.

An object of the present invention is to solve the above-mentioned drawbacks by providing a structure in which the detection conditions of the sensor can be arbitrarily changed, thereby making it possible to perform stable medium detection.
An object of the present invention is to provide a medium detection circuit that can flexibly respond to changes in detection conditions.

[0005]

[Means for Solving the Problems] The medium detection circuit of the present invention is a medium detection circuit that detects a medium such as a sheet of paper, a form, a card, etc. using a sensor. has a comparison detection means for detecting the presence or absence of a medium by comparing it with a predetermined detection condition, and a detection condition changing means for changing the detection condition, and when the presence or absence of the medium cannot be detected as a result of comparison by the comparison detection means. The detection condition is changed by the detection condition changing means, and the presence or absence of the medium is sequentially detected by the comparison detection means based on the changed detection condition.

[0006]

Embodiments Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a medium detection circuit according to an embodiment of the present invention.

In FIG. 1, the medium detection circuit of this embodiment is composed of a sensor sense control section 1, a detection condition setting section 2, a sensor detection section 3, a sensor 4, and a control section 5.

Here, the control section 5 is the sensor sense control section 1.
By giving an instruction to start sensor input, the sensor sense control unit 1 sets the detection conditions for the sensor 4 that have been instructed by the control unit 5 in advance to the detection condition setting unit 2.

[0010] After the sensor sense control section 1 has finished setting the detection conditions for the sensor 4, it issues a command to the sensor detection section 3 to start sensing. Then, when the medium passes through the sensor 4, the sensor detection section 3 sequentially compares the information of the sensor 4 with a predetermined detection condition for the sensor 4 set in the detection condition setting section 2. Then, compare the contents and if they match,
As a medium is detected, the sensor sense control unit 1 is notified that a medium is present.

Furthermore, if the contents are compared and they do not match, the detection condition setting unit 2 is notified that the medium has not been detected, the detection condition setting unit 2 changes the detection condition, and the sensor detection unit 3 detects the detected medium based on the changed detection condition. is compared with the information from sensor 4,
Detects the presence or absence of a medium.

If the medium cannot be detected, the detection conditions are sequentially changed in the detection condition setting section 2 to proceed with medium detection, and finally, if the medium cannot be detected, it is determined that there is no medium.

[0013]

As explained above, the medium detection circuit of the present invention can perform stable medium detection by setting the medium detection conditions of the sensor and changing them as necessary. This has the effect of being able to respond flexibly to changes in conditions.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a medium detection circuit according to an embodiment of the present invention.

[Explanation of symbols]

1 Sensor sense control section 2 Detection condition setting section 3 Sensor detection part 4 Sensor 5 Control section

Claims (1)

[Claims] 1. A medium detection circuit that detects a medium such as a sheet of paper, a form, a card, etc. by a sensor, in which the sensor senses the presence or absence of the medium, and the sensed information is compared with a predetermined detection condition of the sensor. It has a comparison detection means for detecting the presence or absence of a medium, and a detection condition changing means for changing the detection condition, and when the presence or absence of the medium cannot be detected as a result of comparison by the comparison detection means, the detection condition is changed. A medium detection circuit for detecting medium, characterized in that the detection condition is changed by the means, and the presence or absence of the medium is sequentially detected by the comparison detection means based on the changed detection condition.