JPS6147539A - Apparatus for detecting kind of paper of paper feed apparatus - Google Patents

Abstract

PURPOSE:To accurately detect various kinds of papers, by using a reflective type photosensor and discriminating the kind of paper by comparing the output thereof with data preliminarily stored corresponding to the kind of the paper. CONSTITUTION:The paper of an upper cassette is fed to the position of a sensor by the rotation of a call-out roll 10 and an upper paper feeder CL is once turned OFF at said position to stop paper. At this time, the terminal of a light emitting part LED1a is fallen to a LOW level to emit light from an upper sensor LED and, in order to stabilize the light emission of LED and to suppress the curling of the paper at the leading end thereof, slight timing is taken to enter paper detection processing. Herein, the output of the sensor is subjected to A/D conversion and the converted data is compared with the threshold value of paper quality guided from the output characteristic of the paper to perform the judgement of the paper while this judge result is saved in the buffer for the upper cassette of data memory. The judgement of paper quality is performed by comparing the reference value (the output of a light receiving part by said paper) at every sheet of paper and actual data.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a paper feeding device such as a copying machine, and particularly to a paper type detection device.

(Prior Art) Copy paper is available in a wide variety of sizes as well as paper types.

It is common practice to detect and display the type of paper contained in each paper feed section.

Regarding paper size, it is widely practiced to dedicate a cassette and tray for each size, and to read the size indirectly by a combination of a 7-oto interrupter and rIJ and rOJ signals from a reed switch.

However, as for the type of paper, a mechanism that can accurately read it would be proposed. Of course, it is possible to identify paper with clearly different transparency, such as tracing henoku for plain paper. It was not possible to accurately identify each one.

(Purpose) The present invention was made based on this background,
It is an object of the present invention to provide a paper type detection device that can accurately detect various types of paper.

(Structure) Therefore, the present invention is characterized in that a reflective type 7-otosensor is used, and the output thereof is compared with data stored in advance according to the paper type to accurately identify the paper type.

Examples will be described below based on the drawings.

FIG. 1 is a principle diagram for detecting paper quality (paper type).

Reflective type 7 sensor 1 (Figure 3) is a light emitting part (LED)
1α and a light receiving part (7-ototransistor) 1b, and the paper 2 placed between them receives light as shown by the arrow.
and reflected. This paper 2 is placed on a black board 3. Further, IF is the mold temperature flowing through the light emitting section 14, Ia is the current flowing through the light receiving section 1b, and RO is the resistance on the light receiving section 1b side.

FIG. 2 is a characteristic diagram showing the relationship between 1 and 0 due to differences in paper quality. As is clear from the figure, white paper, which has the highest reflectance, best captures light into the light receiving section 1b. Then, in order, they are yellow paper, tracing paper, and OHP film. Of course, other characteristics of various types of paper can also be shown.

Therefore, the paper type can be identified by comparing this characteristic value with the actual measurement value.

FIG. 3 shows a paper feed section of a typical copying machine.

The upper and lower paper feed sections 4.4 have calling rollers 10.10.
The paper passes through the paper feed rollers 5.5 (also passes through the intermediate rollers 6 on the lower stage), is detected by the Ilf sensor 7, and reaches the registration rollers 8. 9 is a drum.

The seven sensors 1.1 are provided between the calling roller 10 and the paper feed roller 5, as shown in the figure.

Figure 4 shows a detection block diagram for processing the paper quality detection signal from the 7-auto sensor 1. The l-chip CPU II, which has a built-in A/D converter, receives the paper quality detection signal from each of the upper and lower paper feed sections. It will be done. Specifically, the input signal of the light receiving section 1b is taken in. - CPU with power
II includes cassette (tray) size, paper remaining amount detection section 1
The signal from 2 is also taken in. C! In the PUII, arithmetic processing as shown in FIG. 5 is performed and outputted to each output section 13, 14.

That is, this is an output to various loads for starting a paper feeding operation, or an output for displaying paper quality.

FIG. 5 is an excerpt of the system Ql 70- when paper is fed from the upper cassette.

First, assume that the upper cassette is selected. Upper paper feed No. 16 is ON When the L preliminary feed timing comes, upper paper feed CL is turned on.
ONL, the paper feed roller 5, and the calling roller 10 rotate, and the paper in the upper cassette is conveyed to the sensor position by the rotation of the calling roller 10.

At this point, the paper carrier feed CL is set to 0FFt to stop the paper.

At this time, the LED 1 (L terminal is set to LOW l, the bell is set to 15, and the upper seven sensor LEDs are made to emit light. In order to stabilize the light emission of the LEDs and to suppress the curling of the leading edge of the paper, paper detection processing is started with a slight timing.

Here, the sensor output is A/D converted, and the converted data is compared with the filter paper quality threshold value derived from FIG. 2 to determine the paper quality. The result of this judgment is then saved in the upper cassette buffer of the data memory. Paper quality is determined by α, b
. . . This is done by comparing the reference value for each paper (light receiving section output for that paper) indicated by X with the actual data.

Therefore, in this case, the reference value α is for the OHP film, and the reference value X is for the yellow paper.

(Effects) As described above, the present invention stores the output data of the 7-bit sensor for each type of paper in the storage unit, and compares this with the actual data to accurately read and identify each type of paper. Therefore, it is possible to make the paper feeding device very convenient for actual use. Wow

[Brief explanation of drawings]

Fig. 1 is a principle diagram of paper type detection according to the present invention, Fig. 2 is a paper output characteristic diagram, Fig. 3 is a schematic configuration diagram of a paper feed section, Fig. 4 is a paper type detection control block diagram, and Fig. 5 is a paper type detection control block diagram. The figure is the operation 70-chart. 1...Reflection type 7 otosensor, 1α...
Light emitting section, 1b... Light receiving section, 11... Chip CPUO Fig. 1 J Fig. 2 IF (mA) Fig. 3

Claims (1)

[Claims] A paper feeding device characterized in that each paper feeding section is provided with a reflective sensor consisting of a light emitting section and a light receiving section, and the paper type is identified by comparing the output of the light receiving section depending on the difference in paper type with a reference value. .