JP2001033214A - Granular material size measuring device and granular material sorter having it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a measurement not effected by the change in projection amount by calculating the size of a granular material from the ratio of granular material light quantity data which is a difference between the photo detecting amount when the granular material is present in a measurement area and a reference photo detecting amount. SOLUTION: When a light receiver, receives light, the light is photoelectrically transduced by a photo detecting element 11 so that an electric signal is transmitted to an amplifying circuit 12 to be amplified. The signal amplified by the amplifying circuit 12 is divided into two parts, and one part is transmitted to a reference value taking circuit 13 to obtain a signal B which is reference light quantity data, and inverted to a signal C by an inverting circuit 14. The other part signal A and the signal C are transmitted to an addition circuit 15 and added to obtain a signal D. The obtained signal D is compared with a preset voltage for sorting, and voltage is compared for determining whether rice passes through a measurement area or not. The signals D and E are compared by a comparison circuit 16, and the signals D and R are compared by a comparing circuit 18. A difference between the thus actually measured rice passing signal A and the reference light quantity (signal B) is obtained to eliminate offset reference light quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring the size of a granular material used for sorting granular materials such as rice and red beans, and a granular material sorting device provided with the same.

[0002]

2. Description of the Related Art Conventionally, as a device used for discriminating the size of granular materials such as rice and red beans, a grain inspection device (Japanese Patent Laid-Open No. 62-30941) and a photoelectric detection device (actually used in Japanese Utility Model) No. 6-21781) is known. In each case, light is emitted from the projector or the like to the particulate matter to be measured,
The size of the granular material is determined based on the amount of light received that is not blocked by the granular material.

[0003]

However, the above-described apparatus has a problem that accurate measurement cannot be performed if the amount of projected light is reduced due to a temporal change of a projector for irradiating the granular material with light. Each of the above devices determines the size of the granular material to be measured based on the amount of light received, and for example, determines that the granular material is small because the smaller the amount of received light, the greater the amount of light blocked by the granular material to be measured. . However, when the amount of projected light decreases due to the above-described temporal change and the amount of received light decreases, it is not possible to determine whether the decrease is due to a temporal change or due to light shielding of a granular material.

[0004] Furthermore, the decrease in the amount of projected light does not occur only with the change over time. All of the above devices are used to determine the size of rice and cereal, and the environment in which they are used is not always clean. Decrease.
This is possible on a daily basis and is a major source of hindrance to accurate measurements.

Accordingly, the present invention is to provide a granular material size measuring apparatus which solves the problem that the size of a granular material cannot be accurately measured due to a change in the amount of projected light, and a granular material sorting apparatus provided with the same. Aim.

[0006]

According to the present invention, there is provided an apparatus for measuring the size of a granular material, comprising: a light projecting means for irradiating light to a granular material arranged in a measuring area; Light receiving means for receiving the light from the light projecting means, and measuring means for measuring the size of the granular material based on the amount of light received by the light receiving means, wherein the measuring means does not include the granular material in the measurement area. Is used as the reference light amount data, and the granular light amount data, which is the difference between the received light amount and the reference light amount when there is a particulate matter in the measurement area, is calculated. It is characterized in that the dimensions of the object are calculated. In this way, by measuring the size of the granular material based on the ratio of the reference light amount data when no granular material exists in the measurement area and the individual granular material light amount measurement data, it is possible to perform measurement independent of the change in the projected light amount. it can.

In the above-described apparatus for measuring the size of a granular material, the light projecting means may output parallel light. By irradiating the granular material with the parallel light in this way, it is possible to suppress a change in the amount of received light due to the position of the granular material in the measurement region.

In the above-mentioned apparatus for measuring the size of a granular material, a plurality of light projecting means and a plurality of light receiving means are arranged opposite to each other via a measurement area, and light from the light projecting means irradiates the granular material from different directions. good. By irradiating the granular material with light from different directions in this way, it is possible to reduce errors due to the light projection direction in the asymmetric granular material.

The above-mentioned granular material size measuring device may further comprise a notifying means, and when the reference light amount data reaches a predetermined value, the notifying means notifies the outside to the outside. By providing the notification means in this way, it is possible to notify the outside when the amount of projected light has changed.

[0010] The granular material sorting means of the present invention comprises the above-mentioned granular material size measuring device, guiding means for guiding the granular material to the measurement area of the granular material size measuring device, and the granular material measured by the granular material size measuring device. Sorting means for sorting according to the size. With such a configuration, it is possible to realize a granular material sorting device capable of sorting granular materials without being affected by a change in the amount of projected light of the device.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described with reference to the drawings. In each of the drawings, the same elements are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a schematic view of a granular material sorting apparatus according to a first embodiment. This granular material sorting apparatus is an apparatus that measures the size of rice and removes rice below a certain size as defective rice. The granular material sorting apparatus includes a supply tank 2 for accumulating rice 1 to be sorted, a vibrating feeder 3 and a chute 4 for guiding the rice 1 sent from the supply tank 2 to a measurement area sandwiched between the light emitter 5 and the light receiver 6. And an air gun 7 arranged downstream of the measurement area.

FIG. 2 is an enlarged perspective view of a part of the granular material size measuring apparatus which is a feature of the present embodiment. Note that FIG.
Are supported by fixing means (not shown).

The light emitter 5 and the light receiver 6 are arranged to face each other to form a measurement area. The light emitting side of the light emitting device 5 and the light receiving device 6
Each of the lenses 8 is disposed between the light receiving side and the light receiving side, and the light emitted from the light projector 5 is made parallel light within the measurement area. The chute 4 for guiding the rice 1 to the measurement area has a hook shape, and the rice 1 is guided by the valley portion to the measurement area. The air gun 7 for sorting the rice 1 is connected to a size determination circuit built in the light receiver 6.

Next, the size determination circuit will be described with reference to FIGS. FIG. 3 is a block diagram showing the configuration of the size determination circuit, and FIG. 4 is a diagram showing the size determination circuit.

Light receiving element 11 forming light receiving surface of light receiver 6
Is constituted by a photodiode, for example, and its current output terminal is connected to the amplifier circuit 12. Amplifier circuit 1
One of the outputs 2 is connected to the adding circuit 15, the other is connected to the reference value extracting circuit 13 for detecting the instantaneous maximum value (reference light amount data) of the signal, and further connected to the inverting circuit 14. ing. The inverting circuit 14 is an adding circuit 15
Here, rice (granular) light quantity data, which is the difference between the reference light quantity data and the actually measured light quantity data, is obtained. The addition circuit 15 is connected to a comparison circuit 16 that compares a set value for rice selection with rice (granular material) light amount data, and further connected to a signal output circuit 17. The signal output circuit 17 is connected to a comparison circuit 18 that performs comparison for determining whether or not the rice 1 has passed, and when the sorting condition is satisfied, the rice 1 is blown off by wind pressure and removed. Connected to a valve drive circuit 19 for controlling the air gun 7 for use.

As shown in FIG. 4, these specific circuits are constituted by operational amplifiers, flip-flops and the like. Incidentally, the output of the comparison circuit 16 is connected to the clock input of DF / F-1, and the output of the comparison circuit 18 is OneShot.
-1 B input. The QB output of DF / F-1 is connected to the D input of DF / F-2, and OneShot
-1 Q output is DF / F-2 clock input and OneSho
Connected to B input of t-2. The QB output of OneShot-2 is connected to the clear inputs of DF / F-1 and DF / F-2. The power supply voltage VCC is applied to the D input and PR input of DF / F-1 and the PR input of DF / F-2, and the A input of OneShot-1 and OneShot-2 is grounded. . The Q output of the DF / F-2 is connected to the base terminal of the transistor via a resistor in the valve drive circuit 19.

The light projector 5 is composed of a light emitting diode (LED) connected between the power supply VCC and the ground.

Next, the operation of the granular material sorting apparatus according to the present embodiment will be described. First, when the operation of the granular material sorting apparatus is started, the rice 1 to be sorted stored in the supply tank 2 is removed.
Is fed little by little from a hole provided at the bottom of the supply tank 2, and the fed rice 1 is guided by the vibrating feeder 3 and the chute 4 to the measurement area, and passes through the measurement area one by one (FIG. 1).

In the measurement area, light is emitted from the light emitter 5 to the light receiver 6. Since the light is parallel light in the measurement area, the same amount of received light can be obtained for the rice 1 of the same size regardless of the change in the path of the rice 1 (see FIG. 5). Thereby, a measurement error due to a change in the path of the rice 1 passing through the measurement area can be reduced.

Next, with reference to FIGS. 3, 4 and 6, the operation of the size determination circuit when the light receiver 6 detects a change in the amount of light will be described in detail. In addition, FIG. 6 shows AL of FIG. 3 and FIG.
FIG. 5 is a diagram showing a signal change in the example.

When light is received by the light receiver 6, the light receiving element 11
The electric signal is transmitted to the amplifier circuit 12 and amplified. As shown in FIG. 6, since the amount of received light decreases due to the passage of the rice 1, the signal A drops to the voltage of 0 V at the timing of the passage of the rice 1.

The signal amplified by the amplifier circuit 12 is branched into two, one of which is transmitted to a reference value extracting circuit 13,
A signal B as reference light amount data is obtained. Then, the signal B is inverted by the inverting circuit 14 to become the signal C.

The other of the branched signals A and C is transmitted to the adding circuit 15 and added. Here, the addition circuit 1
5 is an inverting and adding circuit as shown in FIG.
As shown in signal D, the passing point of rice 1 appears as a positive signal change. Thereby, the light amount (offset) when the rice 1 does not exist in the measurement area can be removed from the detection signal.

Next, the obtained signal D is compared with a set voltage for sorting, and a voltage for determining whether or not the rice 1 has passed through the measurement area (hereinafter, this voltage is referred to as "Inspection voltage"). The set voltage and the test voltage are determined by a ratio with respect to the reference voltage, and are specifically obtained by changing the resistance values of the variable resistors R1 and R2 (see signals E and F in FIG. 6). The comparison circuit 16 compares the signal D and the signal E, and the comparison circuit 18 compares the signal D and the signal F.

The comparison result is input to the signal output circuit 17 and outputs a signal for operating the valve drive circuit 19 when the condition of signal F <signal D <signal E is satisfied.
The air is sent from the air gun 7 to remove the rice 1 satisfying the conditions.
Here, the condition is determined using a flip-flop or the like. Signal changes at points H, J and K connecting the flip-flops and the like are as shown in FIG.

The comparison between the signal D and the signal E is for determining whether or not the target rice 1 has the set size. Is performed because the signal D is smaller than the signal D (the rice 1 is smaller than the set value), it is not possible to determine whether or not the rice 1 is present in the measurement area. .

Here, the granular material sorting apparatus for removing rice of a certain size or less has been described. Conversely, in the case of an apparatus for removing rice of a certain size or more, the rice size is set. If it is determined that the value is larger than the value, it is clear that the rice is present in the measurement area, and it is not necessary to compare with the test voltage.

As described above, the granular material sorting apparatus according to the embodiment has the adding circuit, and the actually measured passing signal of the rice 1 (signal A).
And the reference light amount (signal B), the reference light amount as an offset can be removed.

Since the set value for judging the size of rice is determined by the ratio to the reference light amount (signal B), the rice is stably sorted regardless of the intensity of the light from the projector. be able to. In particular, when sorting agricultural products such as rice or red beans as in the present embodiment, it is used in a harsh environment for a device such as the present embodiment having an optical sensor, and dust that scatters is used for the projector and the receiver. It is easy to get dirty by sticking to windows. In addition, since rice is sorted one by one and takes a long time, the floodlight tends to have heat, and it is difficult to always maintain a constant light emission amount. In addition, since the change in light amount due to shading of the rice or red beans to be measured is small, unless the change in the projected light amount is compensated, the change has a large effect on the measurement result. Therefore, the granular material sorting apparatus of the present embodiment is particularly useful when used in such an environment.

Next, a granular material sorting apparatus according to a second embodiment will be described. The particulate matter measuring device according to the second embodiment has the first
The particulate matter measuring device according to the embodiment is characterized in that two light emitters 5 and two light receivers 6 arranged opposite thereto are arranged, respectively.

FIG. 7 is a view showing a measurement area of the granular material sorting apparatus according to the second embodiment. As shown in FIG.
And the light emitter 21 emit light to the measurement area from a vertical direction, and the light receiver 6 and the light receiver 22 are arranged to face each other.

With such a configuration, it is possible to reduce a measurement error due to the direction of the light irradiated on the rice 1. Since the rice 1 to be sorted usually has an elongated shape rather than a spherical shape, when the light from the projector is irradiated in the major axis direction, the granular material blocks the light in an elliptical shape (FIG. 8A),
When irradiated in the minor axis direction, the light is blocked in a substantially circular shape (FIG. 8)
(B)), which means that the amount of light received by the light receiver is different. However, such inconvenience can be prevented by arranging two projectors and two light receivers and irradiating the measurement region from different directions.

In the second embodiment, the two projectors are arranged so as to irradiate the measurement area from a vertical direction.
It goes without saying that the arrangement is not limited to vertical. It is also conceivable to arrange three or more projectors. Although the measurement accuracy can be expected to be improved by increasing the number of light projectors in this manner, the configuration of the device becomes simpler with a smaller number of light projectors.

Although the granular material sorting apparatus according to the embodiment has been described above, the present invention is not limited to the above embodiment.

For example, an alarm means such as a buzzer is provided on the outer wall of the supply tank, and a comparison circuit for comparing the reference light amount with a predetermined set value is provided in the dimension determination circuit. With this comparison circuit,
When the reference light quantity falls below the predetermined value, a buzzer may be sounded to prompt replacement of the projector or cleaning of the projector.

In the present embodiment, the reference value extracting circuit extracts the instantaneous maximum value of the signal. On the contrary, the reference value extracting circuit may be a circuit that extracts the instantaneous minimum value of the signal. With such a circuit, it is possible to realize a granular size measuring apparatus capable of performing measurement without depending on a change in the amount of light when the amount of light from the projector changes in a direction in which the amount of light increases.

[0038]

According to the present invention, since the size is measured by the ratio to the reference light amount, the measurement can be performed even when the light amount of the light for measuring the size of the granular material changes.

Further, since the measurement area is irradiated with light in parallel, the measurement can be performed irrespective of a change in the path of the granular material passing through the measurement area.

Further, by arranging a plurality of light emitters and light receivers, it is possible to reduce a measurement error due to the direction of light irradiated on the granular material.

[Brief description of the drawings]

FIG. 1 is a schematic view of a granular material sorting device according to a first embodiment.

FIG. 2 is an enlarged perspective view of a part of the granular material size measuring device according to the first embodiment.

FIG. 3 is a block diagram illustrating a configuration of a dimension determination circuit.

FIG. 4 is a diagram illustrating a size determination circuit.

FIG. 5 is an explanatory diagram of a light projector and a light receiver.

FIG. 6 is a diagram showing a signal change of a dimension determination circuit.

FIG. 7 is a diagram illustrating a measurement area of the granular material sorting device according to the second embodiment.

FIG. 8 is an explanatory diagram of rice passing through a measurement area.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rice, 2 ... Supply tank, 3 ... Vibration feeder, 4 ... Chute, 5 ... Projector, 6 ... Receiver, 7 ... Air gun, 11 ... Light receiving element, 12 ...
Amplifying circuit, 13 ... Reference value extracting circuit, 14 ...
Inverting circuit, 15 addition circuit, 16 comparison circuit,
17 ... signal output circuit, 18 ... comparison circuit, 19
..Valve drive circuits, 21,...
・ Receiver.

Continued on the front page F-term (reference) 2F065 AA23 BB07 BB24 DD03 EE03 FF02 HH03 HH13 JJ01 QQ08 QQ25 QQ26 QQ27 TT03 2G051 AA04 AA90 BA01 BA20 CA02 CA07 CB02 DA06 DA13 EB01 EB02 3F026 AC14 CB01 CB02

Claims (5)

[Claims] 1. A light projecting means for irradiating light to a granular material arranged in a measurement area, and arranged opposite to the light projecting means via the measurement area to receive light from the light projecting means. Light receiving means, and measuring means for measuring the size of the granular material based on the amount of light received by the light receiving means, wherein the measuring means is based on the amount of light received when the granular material does not exist in the measurement area. As the light amount data, calculate the granular light amount data that is the difference between the received light amount and the reference light amount when the granular material is present in the measurement area, from the ratio of the reference light amount data and the granular light amount data,
An apparatus for measuring the size of a granular material, wherein the size of the granular material is calculated. 2. The apparatus according to claim 1, wherein said light emitting means outputs parallel light. 3. The light projecting means and the light receiving means are arranged in a plurality facing each other with the measurement area interposed therebetween, and light from the light projecting means irradiates the granular material from different directions. Item 3. The particle size measuring device according to Item 1 or 2. 4. The apparatus according to claim 1, further comprising: a notifying unit, wherein when the reference light amount data reaches a predetermined value, the notifying unit notifies the outside to the outside.
The granular object size measuring device according to any one of claims 1 to 3. 5. The granular material size measuring device according to claim 1, a guiding means for guiding the granular material to the measurement area of the granular material size measuring device, and the granular material size measuring device. And a sorting means for sorting the granular material measured according to the size thereof according to the size of the granular material.