JPH0143177Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a shredder for shredding documents, etc., and in particular a storage section for storing shredded paper sheets (hereinafter referred to as "shredded waste"). The present invention relates to a full paper detection device.

(b) Prior Art Figure 3 shows a schematic structural diagram of a conventionally commonly used shredder. On the upper surface of the shredder main body 1 is an input port 2 into which paper sheets to be processed are input.
is formed, and two sets of cutter rollers 3 are installed inside this inlet 2 in a state that they partially overlap. The cutter roller 3 is made up of a plurality of disc-shaped rotary blades connected in the axial direction. At the bottom of the main body 1, a storage box (accommodation section) 4 is installed to store paper sheets (shredded waste) that have been shredded into strips or strips by the cutter roller 3. This storage box 4 is the main body 1
A door (not shown) provided on the side can be opened to remove and dispose of the stored shredded waste. A micro switch 5 is installed on the inner wall of the main body above the housing box 4 with its hinge lever 6 facing downward. The tip of the hinge lever 6 is located at the upper part of the storage box 4 or above the storage box 4.

In this shredder, the shredded waste shredded by the cutter roller 3 is deposited in the storage box 4, and when the height of the pile reaches the position of the hinge lever 6, the hinge lever 6 is pushed down by the paper sheets and the micro switch 5 is activated. opens and closes. A control unit (not shown) detects this opening/closing state and performs actions to cope with full paper, such as stopping the operation and generating an alarm. In such a shredder, since the hinge lever 6 protrudes above the storage box 4, it is easy to come into contact with the storage box 4 when taking it in or out, and there is a risk of damaging the hinge lever 6. For this reason, there was a problem that care was required when loading and unloading, resulting in poor workability. In addition, the hinge lever 6 prevents the shredded waste from falling evenly, and the hinge lever 6
This caused a delay in detecting full paper, and there was also a risk that shredded waste would overflow into the main body of the device. There was also the problem that the hinge lever 6 swung and malfunctioned due to mechanical vibrations. Furthermore, if the hinge lever 6 is above the storage box 4, it cannot be detected unless the shredded waste exceeds the top edge of the storage box 4, so when the storage box 4 is pulled out, the shredded waste will be scattered inside. I came across a problem.

In order to solve these problems, the present applicant proposed a paper shredder full paper detection device that can accurately detect full paper using an optical method in Utility Application No. 149904/1982.

FIG. 4 shows a schematic structural diagram of a shredder to which the shredder full-sheet detection device is applied. The same parts in the structure as the shredder shown in FIG. 3 are given the same numbers, and the explanation will be omitted. Katsutarora 3
A shielding plate 7 is provided between the storage box 4 and the storage box 4 to block light from the outside. The shielding plate 7 is provided with an opening 7a for dropping shredded paper sheets into the storage box 4. A light emitting section 8 and a light receiving section 9 are provided below the shielding plate 7. Both the light emitting section 8 and the light receiving section 9 are connected to the storage box 4.
It is installed facing inward (downward). As a result, the light emitted by the light emitting section 8 does not directly enter the light receiving section 9, but the light reflected from the upper end of the shredded waste accumulated and stored in the storage box 4 enters.

In this device, as the amount of accumulated shredded debris increases, the reflective surface (the upper surface of the shredded debris) rises and approaches the light emitting section and the light receiving section, so that the amount of light received by the light receiving section increases.
The amount of light received by the light receiving unit when the storage box 4 is full of shredded waste is set as a reference value, and by comparing the actual amount of received light with this, it is possible to detect when the paper is full. .

(c) Problems to be solved by the invention This device has the advantage that it does not have mechanical parts, so it has fewer failures and does not interfere with deposition. However, minute paper dust and the like generated during shredding sometimes adhered to the light emitting section and the light receiving section due to static electricity. In this case, the amount of light received by the light receiving section decreases, and even if the storage box is full, the light receiving section cannot receive a sufficient amount of light, and due to malfunction, shredded waste overflows from the storage box. There was a risk that it would come out.

In view of these problems, this invention provides a paper shredder full paper detection device that eliminates the adhesion of paper dust and prevents malfunctions by forming an antistatic layer on the light emitting surface and the light receiving surface of the light emitting section and the light receiving section. The purpose is to

(d) Means for solving the problem This invention is installed in a shredder that has a shredding section for shredding input paper sheets and a storage section for accumulating and storing the shredded paper sheets. The apparatus includes a light emitting part and a light receiving part provided from an upper end of the accommodating part toward the accommodating part, and when the amount of light received by the light receiving part exceeds a certain value, the paper in the accommodating part is removed. In the shredder full sheet detection device that outputs a message to the effect of the following, an antistatic layer is formed on the light emitting surface and the light receiving surface of the light emitting section and the light receiving section, respectively.

(e) Operation The shredder full paper detection device of this invention operates as follows.

A light emitting part and a light receiving part are installed toward the housing part (so that light does not directly enter the light receiving part from the light emitting part), and the light emitting part irradiates light into the housing part. This light is reflected on the upper surface of the shredded waste deposited and accommodated in the storage section, and the light receiving section receives the reflected light of this light. The amount of light received becomes stronger as the pile height of the shredded debris increases (the closer the reflecting surface is). It determines whether or not the amount of received light is above a certain value (the intensity of reflected light when the top of the shredded waste is at the top of the container), and when it exceeds a certain value, it outputs a message indicating that the paper is full. .

Minute paper dust is generated when shredding, but the light emitting part,
Since an antistatic layer is formed on the light-emitting surface and the light-receiving surface of the light-receiving section, paper dust will not adhere to the light-receiving section, and malfunctions due to a decrease in the amount of light received will not occur.

(f) Embodiment An embodiment of this invention will be described with reference to FIGS. 1 and 2. The structure of the shredder to which this embodiment is applied is similar to the shredder shown in FIG. 4, so a description thereof will be omitted.

FIG. 1 is a diagram showing the appearance of a photoelectric sensor used in a shredder full-sheet detection device according to an embodiment of this invention. This photoelectric sensor 22 has a light emitting section 8 and a light receiving section 9 integrated into one, and a visible light cut filter 12 is installed in front of the photoelectric sensor 22 . The visible light cut filter 12 is a filter that transmits infrared light and is curved into a lens shape to prevent light from diffusing. moreover,
An antistatic layer 13 is formed on the surface of the visible light cut filter 12 to prevent charging due to static electricity. Thereby, adhesion of paper dust etc. can be prevented. As the antistatic layer, a siloxane-based antistatic agent with excellent light transmittance is preferable, but a resin-based one may be used, and a surfactant-based one may also be used as long as it is intended for temporary use.

FIG. 2 is a diagram showing the circuit configuration of the full paper detection device. The light emitting section 8 has a light emitting diode 11 that emits light including infrared light, and the visible light cut filter 12 cuts out light with a wavelength shorter than the infrared light. An oscillator 10 is connected to the light emitting diode 11, which supplies an oscillating current of a specific frequency. This oscillator 10 supplies an oscillating current of 3.3 kHz to the light emitting diode. As a result, the light emitting section 8 irradiates the inside of the storage box 4 with infrared rays whose amplitude is modulated at 3.3 kHz.

On the other hand, the light receiving section 9 has a photodiode 14. The photodiode 14 is an element sensitive to infrared rays and visible light, but since the visible light is cut off by the visible light cut filter 12, it detects only the amount of infrared light. A resistor 15 is connected in series to the photodiode 14, and a reverse voltage of +V is applied to both ends thereof. The reverse resistance value of the photodiode 14 changes depending on the amount of light received by the photodiode 14, and the voltage generated across the resistor 15 changes. This voltage is supplied to a filter 16, and the voltage (output) filtered by the filter 16 is input to an amplifier 17. This filter 16 is connected to the oscillator 10.
This is a bandpass filter that filters only the components of the oscillation frequency (3.3kHz). As a result, out of the light received by the photodiode, only the light emitting diode 1
Only the component of the light emitted by 1 can be extracted. The 3.3kHz component amplified by the amplifier 17 is rectified by the rectifier 18 and converted into a voltage value corresponding to its amplitude. This voltage is input to the compared terminal of the comparator 19. A reference voltage set by voltage +V and reference voltage setting resistors 20 and 21 is input to a comparison terminal of the comparator 19. The comparator 19 outputs "H" when the voltage input from the rectifier 18 exceeds the reference voltage, and prompts the following operating section (not shown) to operate. It is possible to connect a drive stop circuit for the cutter roller 3, an alarm sounding circuit, etc. as a subsequent operating section.

Here, the voltage across the resistor 15 is determined by a photocurrent that is proportional to the amount of light received by the photodiode 14 (not a proportional relationship in a mathematical sense, but a monotonically increasing function). That is,
When the photocurrent increases, the voltage across both ends increases, and when the photocurrent decreases, the voltage across both ends decreases. Of this voltage change, only the 3.3 kHz component (light from the light emitting diode 11) is filtered by the filter 16 and supplied to the amplifier 17. Further, the amplitude of the filtered 3.3 kHz component (that is, the voltage value rectified by the rectifier 18) is proportional to the amount of light received by the photodiode 14. The reference voltage is set to a voltage value output by the rectifier 18 when the storage box 4 is full. Thereby, when the storage box 4 is full of shredded waste, the cutter roller drive stop circuit, alarm sounding circuit, etc. can be operated.

Furthermore, the antistatic layer is transparent and does not affect light transmission.

In this embodiment, a photoelectric sensor 22 in which the light emitting part 8 and the light receiving part 9 are integrated is used, but the light emitting part and the light receiving part may each be composed of separate elements and installed on the opposite side of the top surface of the device. good.

In addition, in this example, by modulating the detection light, it is easy to distinguish between external light and the detection light, and by using infrared rays as the detection light, the reflectance depending on the color of the shredded waste can be improved. This further improves detection accuracy.

(g) Effect of the invention According to this invention, the light emitting surface of the light emitting part and the light receiving part,
By forming an antistatic layer on the light-receiving surface, it is possible to prevent the adhesion of paper dust, etc., reducing the amount of light emitted when paper dust adheres to the light-emitting part and the amount of light received when paper dust adheres to the light-receiving part. can eliminate the decrease in This eliminates malfunctions in which full paper is not detected because the amount of light received does not reach a predetermined value even when the shredded waste reaches the upper end of the storage section, and it is possible to eliminate overflow of the storage section and damage to the cutter roller. .

[Brief explanation of the drawing]

Figure 1 is an external view of a photoelectric sensor used in a shredder full-sheet detection device, which is an embodiment of this invention.
FIG. 2 is a diagram showing the circuit configuration of the paper-full detection device of the shredder, and FIGS. 3 and 4 are schematic structural diagrams of the conventional shredder. 8... Light emitting section, 9... Light receiving section, 11... Light emitting diode, 12... Visible light cut filter, 13
...Antistatic layer, 14...Photodiode, 1
9... Comparator.

Claims (1)

[Scope of Claim for Utility Model Registration] A device installed in a shredder having a shredding section for shredding input paper sheets and a storage section for accumulating and storing the shredded paper sheets, A shredder having a light emitting part and a light receiving part provided from an upper end of the storing part toward the storing part, and outputting a message that the storing part is full when the amount of light received by the light receiving part exceeds a certain value. 2. A full sheet detecting device for a shredder, characterized in that an antistatic layer is formed on the light emitting surface and the light receiving surface of the light emitting section and the light receiving section, respectively.