JPS6148754B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a card-shaped paper feeding device in a computer terminal device, a printing device, or the like.

This type of paper feeding device is generally provided with a mechanism that prevents two or more sheets of paper from being fed in an overlapping manner at a time. However, even if such a blocking mechanism is provided, there are rare cases where two or more sheets are overlapped and sent at the same time for some reason. For this reason, a mechanism for detecting the thickness of the paper being fed is generally provided after the two-sheet feeding prevention mechanism, and when the detected value becomes larger than a reference value, a signal indicating an abnormality in the paper feeding operation is sent. generate,
Either an error message is displayed or the feed operation is stopped.

Now, when actually using a paper feeder with such a configuration, it is necessary to set the above-mentioned reference value according to the thickness of the paper being used. Conventionally, the operator had to judge the paper thickness empirically. The reference value was set by manually operating a switch. However, determining the paper thickness based on the operator's judgment requires a fairly high level of specialized knowledge, as the variety of paper types has increased, making it extremely difficult for anyone to operate easily. I'm getting used to it.

Therefore, the present invention solves the above-mentioned problems of the prior art, and an object of the present invention is to provide a paper feeding device that can be easily operated even by a person without special knowledge regarding paper thickness. .

In order to achieve the above-mentioned object, the present invention includes a gate mechanism that prevents the feeding of multiple overlapping sheets of paper, and a gate mechanism that is provided after the gate mechanism, detects the paper thickness, and outputs a signal corresponding to the paper thickness. a selection switch connected to an output terminal of the detection device;
a device connected to the output terminal of the detection device by selection of one of the selection switches and storing the output level of the detection device; and a device connected to the output terminal of the detection device by selection of the other selection switch; A paper feeding device is provided, comprising a device connected to the storage device and detecting an abnormality in the output of the detection mechanism by comparing the output with the output of the storage device.

The present invention will be explained in detail below with reference to the drawings.

The drawing represents the configuration of one embodiment of the present invention. In the figure, reference numeral 10 denotes a hopper on which sheets 11 to be fed are stacked. The sheets 11 in this hopper are sequentially sent out to the left in the drawing by a sending mechanism 12, and pass through a two-sheet feeding prevention mechanism 13. In this embodiment, this blocking mechanism 13 is a feed roller 13a.
and the separation roller 13b which has a relatively slow circumferential speed with respect to the feed roller 13a or has stopped.
The paper 11 passes between both rollers, and due to the frictional forces in opposite directions generated on both sides of the paper 11, the paper 11 is
This prevents feeding of more than one sheet. A light emitting element 14 and a light receiving element 15 are provided downstream of the blocking mechanism 13, that is, in the paper feeding direction, so as to sandwich the passing paper. The light emitting element 14 is made of, for example, an incandescent bulb, a light emitting diode, etc., and irradiates light with a constant luminous intensity in the direction of the light receiving element 15. Light receiving element 15
is composed of a photoelectric conversion element such as a photodiode, phototransistor, photocell, etc., and is configured so that its output current, that is, photocurrent, is applied to the current-voltage conversion circuit 16. The output of the conversion circuit 16 is sent to the level hold circuit 1 via a selection switch 17 composed of, for example, an analog switch.
8 or one of the input terminals of the comparison circuit 19. The output of the level hold circuit 18 is applied to the other input terminal of the comparison circuit 19, and the output of the comparison circuit 19 is applied to the abnormality occurrence indicator 20 or via the line 21 to the feed operation control circuit ( (not shown).

Next, the operation of this embodiment will be explained. The operator first confirms that the output of the conversion circuit 16 is connected to the level hold circuit 1.
The selection switch 17 is set so that the voltage is applied to the signal 8. In this state, the paper 11 to be fed is
Only one sheet is passed between the light emitting element 14 and the light receiving element 15 of the paper feeding device. Since there is a specific relationship between the light transmittance and the thickness of the paper 11, this causes the level hold circuit 18 to have a voltage value corresponding to the thickness of one paper, or a voltage value corresponding to the thickness of two paper sheets. This means that a voltage value that is biased toward the corresponding voltage value side is stored. Next, the operator switches the selection switch 17 to the opposite side, ie, so that the output of the conversion circuit 16 is directly applied to the comparison circuit 19, and starts the paper feeding operation.

When sheets are fed one by one, the comparison circuit 19 does not generate an abnormality signal, but when two or more sheets are fed at once, the output voltage of the conversion circuit 16 becomes the output voltage of the level hold circuit 18, i.e. Since the threshold value is crossed, an abnormality occurrence signal is outputted from the comparison circuit 19, and the paper feeding operation is stopped either by energizing the abnormality occurrence indicator 20 or by the action of the feeding operation control circuit.

As described above, according to the present invention, the standard value of paper thickness for detecting an abnormality in paper feeding operation can be automatically set simply by passing one sheet of paper through the detection mechanism. Therefore, it can be easily operated even by a person without special knowledge regarding paper thickness, and since the same detection mechanism is used to set the reference value and detect abnormalities, it is extremely resistant to deterioration of the detection mechanism. It is valid.

In the above-mentioned embodiment, a mechanism that measures the light transmittance of the paper is used as the paper thickness detection mechanism, but this is a mechanism that directly measures the paper thickness mechanically and converts it into an electrical signal. It's okay to be.

[Brief explanation of the drawing]

The figure is a configuration diagram of an embodiment of the present invention. 10...Hopper, 11...Paper, 12...Feeding mechanism, 13...2-sheet feeding prevention mechanism, 14...
Light emitting element, 15... Light receiving element, 16... Current voltage conversion circuit, 17... Selection switch, 18... Level hold circuit, 19... Comparison circuit, 20... Abnormality occurrence indicator.

Claims (1)

[Scope of Claims] 1. A gate mechanism that prevents the feeding of multiple sheets of paper in duplicate; a detection device provided after the gate mechanism that detects paper thickness and outputs a signal corresponding to the paper thickness; a selection switch connected to an output terminal of the device; a device connected to the output terminal of the detection device by selection of one of the selection switches and storing the output level of the detection device; and a device connected to the output terminal of the detection device by selection of one of the selection switches; A paper feeding device comprising: a device that is optionally connected to an output terminal of the detection device and detects an abnormality in the output of the detection mechanism by comparing the output with the output of the storage device. 2. The paper feeding device according to claim 1, wherein the detection device comprises a mechanism that indirectly detects the paper thickness by measuring the light transmittance of the paper.