JPH01199683A - Shell screening machine and screening method for nuts - Google Patents

Abstract

PURPOSE:To execute efficient screening by providing a light projecting means which projects light on a mixture and a detecting means which selectively detects only the near IR rays among the reflected light rays from the mixture. CONSTITUTION:Materials to be screened in which the seeds and shells of nuts are mixed are released from a belt conveyor and fall along the prescribed track. A sensor 6 keeps receiving the near IR rays and outputs an electric signal by converting the light to said signal. The sensor 6 receives the near IR rays reflected from the body of the nut if the body of the nut passes an observation section X. The level of the IR rays reflected from the body is the same as the level of the IR rays irradiated from the background. The level of the near IR rays in the wavelength received by the sensor 6 increases and the voltage level of the voltage signal outputted from the sensor 6 temporarily exceeds a selection standard when the shell passes the observation section X. The signal is supplied to a monostable multivibrator 14 during this time.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a nut shell sorting machine and a sorting method for sorting and removing shells from a mixture of nut meat and shells that are sequentially and continuously transferred.

(Prior Art) Nuts are usually covered with a hard shell on the outside, and in order to eat them, the outer shell must be broken and the flesh inside must be taken out. Processing machines that perform such operations continuously are well known.

By the way, conventional processing machines use the difference in specific gravity or wind force to separate the cracked shell from the flesh, but the shell cannot be completely removed and must be removed manually at the final stage, which is very difficult. It took a lot of time.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a nut shell sorting machine that can sort out and eliminate shells that cannot be removed using conventional processing machines.

(Means for Solving Problems) In order to achieve the above object, the present invention irradiates light onto a mixture of nut meat and shells that are continuously transported, and selects and eliminates the shells based on the difference in reflected light. a light irradiation means for irradiating the mixture with light; a detection means for selectively detecting only near-infrared rays from the light reflected from the mixture; The present invention is characterized by comprising a discriminating means for discriminating whether the shell is present or a shell, and an eliminating means for excluding the shell from the mixture based on the discrimination result of the discriminating means.

Further, the present invention is characterized in that the detection means includes a selection means for selectively passing only near-infrared rays.

Further, the present invention is characterized in that the selection means allows light having a wavelength near BGhm to pass through.

(Function) As is clear from Figure 2, the reflectance of light in the near-infrared region between the shell and the meat is significantly different, especially around wavelengths of 12 (10 nm).Using this property, the shell and the meat can be distinguished. do.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a sorting machine according to an embodiment of the present invention. In this figure, A and A' are nut meat and shell, respectively, and these meat A and shell A' are discharged from a chute or belt conveyor (not shown) so that they always pass through observation section X on the same trajectory. Ru.

On the other hand, 1 is an illumination light bulb that irradiates light to the above-mentioned observation section X, and a tungsten light bulb or a halogen light bulb that generates light in the near-infrared region is used.

The light from the light bulb 1 is irradiated onto the body A or shell A° of the object to be sorted passing through the observation section X, and is reflected by the object to be sorted. Reflected by the object to be sorted, the light passes through various optical elements 2.3.4 and 5 arranged sequentially from front to rear and reaches the sensor 6.

Among the optical elements described above, the first lens 2 is arranged at the forefront, and this first lens 2 directs the light reflected by the object to be sorted onto the optical element at the rear stage, that is, the slit 3. Focus light. The slit 3 narrows the incident light range to the observation section X, and allows only the light from the observation section X to pass through a limited amount. The light that has passed through the slit 3 passes through an optical element, that is, a filter 4, arranged behind the slit 3. The filter 4 filters the light that has passed through the slit 3 with a wavelength of 12 Ham.
Only nearby near-infrared rays are selectively passed through and sent to the subsequent optical element, that is, the second lens 5. The second lens 5 focuses the near-infrared rays that have passed through the filter 4 onto the sensor 6 .

The sensor 6 converts the collected light into an electrical signal and outputs it. At this time, the voltage of the electric signal increases as the intensity of the received light increases, and decreases as the intensity of the received light decreases.

In general, the body and shell of a nut have different light reflectances. This is in the near-infrared region, especially the wavelength is 120 as shown in Figure 2.
At around Onm, the shell reflects more infrared rays than the body. In the present invention, this difference in reflectance is used to distinguish between the body and the shell. That is, the intensity of the near-infrared light having a wavelength of 120 hm, which is received by the sensor 6, changes depending on whether the flesh or the shell of the nut passes through Kankyoto X.

When the shell passes through, the light is strong, and when the body passes through, the light is weak. That is, the voltage of the electric signal output from the sensor 6 is high when the shell passes, and low when the body passes. By detecting the level of this voltage, it is determined whether the object to be sorted is meat or shell.

Incidentally, the sensor 6 constantly outputs electrical signals in accordance with the intensity of the received light. That is, the sensor 6 outputs an electric signal according to the intensity of the received light even after the object to be sorted passes through the observation section X until the next object to be sorted passes through the observation section X.

The signal during this period is not only unnecessary, but also extremely unstable, and unless some measure is taken, the device may malfunction.

In the present invention, a background is placed on the back side of the observation section X, that is, on an extension of the sensor 6 and the observation section X, and with this background,
The level of light received by the sensor 6 during the above-mentioned period is adjusted to be the same as when the nut meat passes through.

The background consists of a translucent background plate 7 and a background adjustment light bulb 8, and the background adjustment bulb 8 is illuminated with a predetermined intensity and a wavelength of 1200. It is adjusted to emit near-infrared rays of m. In other words, the background adjustment light bulb 8 is configured such that the intensity of the near infrared rays emitted by the background adjustment electrode 8 through the semi-transparent plate 7 is equal to the intensity of the near infrared rays reflected and output by the nut's body when passing through the observation section X. adjusted to be the same. As a result, after the object to be sorted passes through the observation section I will do it. Therefore, for example, while only the body is passing continuously, the voltage of the electrical signal output from the sensor 6 is always constant, resulting in an extremely stable signal. If the shells are mixed, only when the shells pass through the observation section X, the voltage of the electrical signal output from the sensor 6 temporarily increases. That is, when the shell passes through one observation section X, the sensor 6 outputs a pulse-like signal.

The electrical signal output from the sensor 6 is supplied to a preamplifier 9. Preamplifier 9 amplifies the electrical signal output from sensor 6 and supplies it to amplifier 11 via capacitor IO. As a result, the electrical signal output from the preamplifier 9 has noise removed, is further amplified, and is supplied from the amplifier 11 to the first input terminal of the comparator 12. On the other hand, a second input terminal of the comparator 12 is supplied with a selection reference voltage from a selection reference voltage circuit 13 . This selection reference voltage is lower than the voltage output from the amplifier 11 when the nut shell passes through the observation section X, and when the nut shell passes through the observation section X or simply receives light from the background. The voltage is higher than the voltage output from the amplifier 11 when the voltage is on. Moreover, this selection reference voltage is adjustable.

As a result of the selection reference voltage being set as described above, when the nut shell passes through the observation section output, monostable multivibrator 14
is supplied to

When the detection signal is output from the comparator 11, the monostable multivibrator 14 outputs a pulse signal with a predetermined pulse width of I and supplies it to the delay circuit 15.

The delay circuit 15 includes a counter 15a, an oscillation circuit 15b, and a timing adjustment circuit 15c. The oscillation circuit 15b oscillates at a period determined by the timing adjustment circuit 15c, and supplies a clock signal to the counter 15a. The counter 15a counts the clock signal supplied from the oscillation circuit 15b, delays the input signal by a predetermined time, and outputs the delayed signal. That is, the counter 15a delays the signal output from the monostable multi-bi break 14 by a predetermined time and outputs the signal. This delay time can be changed by adjusting the timing adjustment circuit 15c and changing the cycle of the clock signal output from the circuit 15c.

The delay signal output from the counter 15a is supplied to the drive circuit 16. The drive circuit 16 includes a delay circuit 15
When the delay signal is supplied from the ejector 17, the ejector 17 is activated. The ejector 17 is a type of electromagnetic valve, and is arranged along the trajectory of the object to be sorted. This ejector 17 is activated by the drive circuit 16 and blows compressed air onto the object to be sorted as it passes in front of it.

The time from when the shell passing through the observation section X is detected to when the ejector 17 blows out air is determined by the delay circuit 15 described above. This time is equal to the time from when the shell passes through the observation section X until it reaches just before the ejector 17.

The shells blown off by the ejector 17 fall into a dedicated disposal box 18. On the other hand, the nut meat continues to fall along the initial trajectory and falls into the care box 19.

The operation of the sorting machine having the above configuration will be explained. The material to be sorted containing the nut meat and shell is discharged from a chute or belt conveyor (not shown) and falls along a predetermined trajectory. On the other hand, the sensor 6 constantly receives near-infrared rays with a wavelength of 120 On+++ emitted from the adjustment light bulb 8 in the background, and converts this light into an electrical signal and outputs it. When the sensor 6 receives light from the background, the amplifier l
The voltage level of the electric signal outputted from the selection reference voltage circuit 13 is lower than the selection reference voltage outputted from the selection reference voltage circuit 13, and therefore, no detection signal is outputted from the comparator 12.

This will be further explained using FIG. The voltage level of the output signal (a) of the sensor 6 detecting near-infrared rays from the background is:
This is the so-called "background level" shown. Therefore, it is lower than the "selection standard" defined by the selection reference voltage of the selection reference voltage circuit 13, and no detection signal is output from the comparator 12.

When the body of the nut passes through the observation section X, the sensor 6 detects the wavelength of 1200 noon reflected from the body
receives near-infrared rays. The level of the infrared rays reflected from the body is the same as the level of the infrared rays irradiated from the background described above, and therefore the voltage level of the electrical signal output from the sensor 6 hardly changes. That is, the times T, , T in Fig. 3
The signal is only slightly fluctuating as seen in ,
The signal level never exceeds the "screening criterion".

As a result, the drive circuit 16 does not operate, and the body passes just in front of the ejector 17 and falls into the Natsu exclusive box 19.

On the other hand, when the shell passes through the observation section The voltage level of the signal temporarily becomes a “selection criterion”
′ exceeds. As a result, while the output of the sensor 6 exceeds the "selection criterion" (Δ1,), a detection signal is output from the comparator 12 (see FIG. 3(b)) and is supplied to the monostable melt-by-break 14. .

The detection output of the comparator 12 serves as a trigger, and a pulse signal with a pulse width Δt is supplied from the monostable multivibrator 14 to the delay circuit 15 (see FIG. 3(c)).

As a result, the extension circuit 1 is delayed by time Δt3 from the detection of the shell.
A signal is output from 5 (see FIG. 3(d)). As a result, air is ejected from the ejector 17 at time T4.

On the other hand, the shell that has passed through the observation section X at time T passes just in front of the ejector 17 at time T, after which time Δt has elapsed. Therefore, the shell of the ejector 17 is blown away by the blown air and falls into the waste box 18. In this way, the shell and flesh of the nuts are sorted.

(Effects of the Invention) As explained above, the present invention provides a nut shell sorting machine that irradiates light onto a mixture of nut meat and shells that are sequentially and continuously transported, and selects and eliminates shells based on differences in reflected light. a light irradiation means for irradiating the mixture with light; a detection means for selectively detecting only near-infrared rays from the light reflected from the mixture; Since it is equipped with a discriminating means for discriminating whether it is a shell, and a removing means for removing shells from the mixture based on the discrimination result of the discriminating means, it is not necessary to rely on human labor to remove shells that cannot be removed by conventional processing machines. It can be sorted and eliminated, and work efficiency can be significantly improved.

Since the reflectance of near-infrared rays with a wavelength of Bllhm is most different between the shell and the flesh of a nut, if the detection is focused on near-infrared rays with a wavelength of HOO++a, errors in selection will be eliminated and the reliability of the device will be improved.

If a background device is installed that emits light at the same level as the reflected light reflected by the shell or flesh of the nut, it is possible to The level of the detection signal is stabilized, and the device will not malfunction during that time.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a sorting machine according to an embodiment of the present invention, FIG. 2 is a graph showing the difference in light reflectance between nut shells and nuts in the near-infrared region, and FIG. It is a timing chart showing the operation of the same sorting machine. 1: Light bulb for illumination (light irradiation means), 2: First lens, 3 Nislit, 4: Filter (selection means), 5: Second lens, 6: Sensor (detection means), 9.1
0: Amplifier, 12: Comparator (discrimination means), 17: Ejector (exclusion means), A: Nut meat, A': Nut shell.

Claims (7)

[Claims] (1) In a nut shell sorting machine that irradiates light onto a mixture of nut flesh and shells that are continuously transported one after another and sorts out the shells based on differences in reflected light, a light irradiation means that irradiates the mixture with light; , a detection means for selectively detecting only near-infrared rays among the reflected light from the mixture; and a discrimination means for discriminating whether the irradiated object is a body or a shell based on the detection result of the detection means. A nut shell sorting machine comprising: a removal means for removing shells from the mixture based on the discrimination result of the discrimination means. (2) The nut shell sorting machine according to claim 1, wherein the detection means has a selection means that selectively passes only near-infrared rays. (3) The nut shell sorter according to claim 2, wherein the selection means passes light having a wavelength of around 1200 nm. (4) The nut shell sorting machine according to any one of claims 1 to 3, wherein the light irradiation means irradiates near-infrared rays. (5) The nuts according to any one of claims 1 to 4, further comprising a background device that irradiates light at the same level as the reflected light reflected by the shell or flesh of the nut. Shell sorting machine. (6) A nut shell sorting method in which a mixture of nut bodies and shells that are sequentially and continuously transported is irradiated with light and the shells are sorted out based on the difference in reflected light, in which the mixture is irradiated with light and the same mixture is selectively detects only the near-infrared rays of the reflected light from A method for sorting nut shells, which is characterized by removing shells. (7) The method for sorting nut shells according to claim 6, characterized in that near-infrared rays having a wavelength of around 1200 nm are detected.