JPS61212734A - Automatic light dimmer for color selection machine - Google Patents

Abstract

PURPOSE:To achieve a higher selection of the titled device accuracy, by detecting the quantity of light of a light source continuously with a second light receiving sensor while the detection signal thereof is inputted into a smoothing amplifier and averaged to actuate a dimmer according to the signal voltage to be outputted from the smoothing amplifier. CONSTITUTION:The quantity of light of a light source 11 is detected with a second light receiving sensor 16 provided near a detector section and the detection signal thereof is amplified 27 in inversion to be averaged with an integration smoothing amplifier 28. The output signal from the amplifier 28 is inputted into a pulse generator 29 to control the phase angle of current of the light source 11 with the generator 29 and a triac 30 and as the output voltage from the amplifier 28 falls, the quantity of light increases. As a result, the quantity of light detected with a first light receiving sensor increases and the output signal from a main amplifier due to colored particles returns to the initial voltage to remove the colored particles with an ejector. Thus, the selection accuracy can be elevated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a color sorting machine that irradiates grains with light and discriminates and sorts colored grains based on the amount of reflected light and the amount of transmitted light.

Prior Art Conventionally, in this type of color sorting machine, grains are flowed down by a flow device, and a background (
reference color plate), light receiving sensor.

A detection unit consisting of a light source and an injection nozzle device are appropriately arranged, and a light receiving sensor detects the difference between the amount of light obtained by irradiating the grains flowing down along the flow device from the light source and the amount of light from the background. However, it is known that the signal is communicated to the control circuit of the injection nozzle to operate the injection nozzle device and remove the colored particles with a blast of air.

Problems to be Solved by the Invention By the way, while the colored grains are jet-removed by the jet nozzle device over a long period of time, dust2), foreign matter, moisture, etc. contained in the raw material grains are removed from the light source of the detection unit, the background Adhesion to the ground and light-receiving sensor caused a decrease in sorting accuracy.

Therefore, a transparent wall for dustproofing is provided in front of the detection section, and a cleaning device for the transparent wall surface is provided (Japanese Patent Laid-Open No. 55
-149667) or JP-A-51-275, which allows adjustment of the amount of background light.
Publication No. 68) was proposed.

However, in those equipped with the above-mentioned cleaning device, each time the cleaning device moves through the transparent wall soil, the irradiation from the light source and the amount of light detected by the light receiving sensor are interrupted, so the supply of raw material grain must be stopped each time. Also, since the color sorter is usually provided with detectors facing each other, and the detectors are usually provided with several tens of channels, a large number of background light amount adjustment devices are required. This complicates the detection section accordingly, and in addition, maintenance and inspection of the light amount adjusting device becomes troublesome.

In view of the above, the present invention has been developed in such a way that even if the amount of light detected by the light receiving sensor is attenuated due to dust attached to the detection part 2), foreign matter, etc., or even if the amount of light detected by the light receiving sensor is increased by removing the dust, the amount of light from the light source is It is an object of the present invention to provide an automatic light control device for a color sorter that can increase or decrease the detection sensitivity and always maintain a constant detection sensitivity.

Means and Effects for Solving Problems The present invention provides a second light receiving sensor that detects the amount of light from a light source near the detection section, and a smoothing amplifier that inputs the detection signal of the second light receiving sensor. and is configured to operate a light control device of the light source in accordance with the output of the smoothing amplifier.

2) As a result, the light intensity of the light source is continuously detected by the second light receiving sensor, and this detection signal is input to the smoothing amplifier, averaged, and adjusted according to the signal voltage output from the smoothing amplifier. Operate the light device to adjust the light intensity of the light source.

Example Embodiments of the present invention will be described based on the drawings.

FIG. 1 shows a longitudinal section of an embodiment of the present invention, and FIG. 2 is an enlarged view of the same part.

Reference numeral 1 designates a tank into which raw grains are input, 2 a vibrating supply gutter that supplies the grains in the tank 1 to a chute 4, and 3 an oscillator that applies vibration to the vibrating feed gutter 2. 4
is a tilted chute 2) whose upper end is connected to the vibrating supply gutter 2, and the lower end of the chute 4 faces into the sorting chamber 5, and near the lower end of the chute 4 there is a falling trajectory A of the grains. A pair of detection units 6 are provided sandwiching each other. 7 is an ejector (one end connected to an air compressor (not shown)).
ejector), 8 is a fine grain vibrator 2), which is located on the falling trajectory A and is provided so as to guide the grains not removed by the ejector to a container or the like (not shown).

Reference numeral 9 denotes a colored grain discharge port for discharging the colored grains removed from the falling trajectory A by the ejector 7. Reference numeral 1o designates a partition plate 2) provided in the sorting chamber 5, which is provided so that the colored particles blown away by the ejector 7 are allowed to fall into the colored particle discharge port below without scattering into the sorting chamber 5.

In the detection unit 6, reference numeral 11 is a dimmable light source 2) made of a fluorescent tube or the like, which illuminates the grains passing through the sorting chamber 5. Reference numeral 12 denotes a background composed of a tungsten light bulb or the like 2), and a control volume is provided in the background to adjust the amount of light from the light bulb in accordance with the grains to be sorted. Reference numeral 13 is a light receiving sensor consisting of a photodiode, etc. 2), and the light receiving sensor 13 of one detection section is connected to the background 1 of the other detection section 6.
2 and are provided opposite each other. 14 is a condensing lens (
It is a lens barrel equipped with a single-convex lens), a filter, etc.

Reference numeral 15 denotes a transparent wall 2) for dustproofing, which isolates the sorting chamber 5 from the detection section 6 and is detachably provided. 16 is a second light receiving sensor consisting of a phototransistor etc. 2)
The light receiving sensor 16 is provided near the detection section 6 and detects the amount of light (brightness) from the light source 11. Reference numeral 17 denotes a nozzle that intermittently blows air toward the second light receiving sensor 16 2), and the nozzle 17 is connected to the same air compressor as the ejector 7 .

Reference numeral 18 denotes a control unit, and 19 denotes an operation panel 2). The operation panel 19 is provided with an oscilloscope (not shown) so that signals from the light receiving sensor can be observed. 20 is a power supply section.

FIG. 3 is a schematic circuit diagram showing a control circuit for the ejector 7 provided in the control section 18.

13 is a light receiving sensor, 21 is a head amplifier, and 22 is a main amplifier 2). The main amplifier 22 is provided with a volume VR+ for gain adjustment. 23 is a comparator 2), and a level (reference voltage) control volume VR2 of the comparator 23 is provided on the operation panel 19. 24 is a monostable multivibrator (one shot) 2), the monostable multivibrator 2
4 is the injection time adjustment volume VR3 of the ejector 7.
is provided. 25 is an OR gate, 26 is a transistor that forms the valve gate of the ejector 7 2),
P is a power source for the ejector 7.

FIG. 4 is a schematic circuit diagram of an automatic light control device for the light source 11 in this embodiment. 16 is a second light receiving sensor, 27 is an inverting amplifier, 28 is an integral smoothing amplifier, 29 is a pulse generator consisting of a V/F converter, and 30 is a triac (bidirectional thyristor).

Next, in the above example, colored grains (brown rice, brown rice,
We will explain the action when separating green rice, etc.) and foreign substances.

The polished rice put into the tank 1 is supplied in fixed amounts to the chute 4 by the vibrating supply gutter 2, slides down the bottom of the chute 4, which has a V-shaped cross section, at an accelerated rate, and falls from the lower end of the chute 4 along a falling trajectory A. As shown, the grains fall through the sorting chamber 5, are guided by the refined product vibrator 8, and are collected in a container or the like.
is illuminated by a light source 11. The light amount of the background 12 and the amount of transmitted light and reflected light from the polished rice particles are detected by the light receiving sensor 13 via the condenser lens and filter of the lens barrel 14.

The signal detected by the light receiving sensor 13, that is, the difference between the amount of light from the background 12 and the amount of light from the polished rice particles is:
First, the signal is inverted and amplified by the head amplifier 21, and further amplified by the main amplifier 22 to a voltage that can be easily processed by the comparator 23. (This amplified signal is observed by an oscilloscope provided on the operation panel 19.) The signal output from the main amplifier 22 is input to a comparator 23 and compared with a certain level (reference voltage, for example, 5V). Ru. Note that the level is adjusted as appropriate with a level control volume VR2.

Then, the signal that has risen above the level, that is, the signal when the difference between the amount of light from the background 12 and the amount of light from the particles is large (signal due to colored particles) is input to the monostable multivibrator 24 and one-shot Signal and Na2)
, this one-shot signal is input to the valve gate transistor 26 via the OR gate 25 to operate the ejector 7. In this way, compressed air from an air compressor is injected from the ejector 7, and the colored particles are blown away from the falling trajectory A and discharged from the colored particle outlet 9 to the outside of the machine.

As mentioned above, colored grains etc. in polished rice are sorted out, but as the sorting continues for a long time, the detection part 6
As dust and the like adhere to the transparent wall 15 of the transparent wall 15, the amount of light detected by the light receiving sensor 13 is attenuated. Therefore, for example, initially,
The signal from the colored particles is output from the main amplifier 22 as a signal 6. The signal from the colored particles was removed by the ejector 7 via the monostable multivibrator 24, but as the amount of light detected by the light receiving sensor 13 attenuated, the signal from the colored particles decreased to level (5
V) The following signals are generated. 2) The colored particles are not removed by the ejector 7 and are mixed into the refined product.

In this way, when dust etc. adhere to the transparent wall 15 of the detection section, the amplitude of the output waveform appearing on the oscilloscope becomes small2) as a whole, and the peak value of the waveform due to colored particles also becomes below the level. be.

On the other hand, in the light control device for the light source 11 shown in FIG.
The signal is inverted and amplified by the integral smoothing amplifier 27, and then averaged by the integrating smoothing amplifier 27. The output signal from the integral smoothing amplifier 28 is input to a pulse generator 29, and the phase angle of the current of the light source 11 is controlled by the pulse generator 29 and the triac 30. The light source 11 is formed so that when the output voltage from the light source 28 decreases, the amount of light from the light source 11 increases accordingly. 2) As a result, the amount of light detected by the light receiving sensor 13 increases, and the output signal from the main amplifier 22 due to the colored particles increases to the original voltage (6).
and is removed by the ejector 7. Note that dust and the like adhering to the second light receiving sensor 16 are intermittently cleaned by the nozzle 17.

FIG. 5 shows a light source dimmer device showing a second embodiment of the present invention2), 11 is a light source made of a fluorescent tube, 31 is a light shielding body2), and the light shielding body 31 covers the light source 11. At the same time, a light projection window 32 is provided in the longitudinal direction. 33, 34, and 35 are gears that transmit the rotation of the pulse motor 36 to the light shielding body.

FIG. 6 is a control block diagram of the pulse motor 36. 27 is an inverting amplifier, 28 is an integral smoothing amplifier, 37 is an A/D converter, and 36 is a pulse motor.2) The pulse motor 36 is provided with a zero point detector consisting of a limit switch and the like.

38 is a pulse motor drive circuit.

In this embodiment, the second light receiving sensor 1
The operation in which the signal detected by 6 is smoothed and amplified through the inverting amplifier 27 and the integral smoothing amplifier 28 and is output is the same as in the first embodiment.

The signal output from the integral smoothing amplifier 28 is input to a pulse motor drive circuit 38 via an A/D converter 37. When the output voltage from the integral smoothing amplifier 28 decreases, the light projection window 32 of the light shield 31
The pulse motor 36 is driven by an appropriate number of pulses so as to rotate toward the side, thereby increasing the amount of light irradiated from the light source 11 onto the falling trajectory A (2).

The rotational movement of the light shielding body 31 is such that the light projection window 32 is rotated when the transparent wall 15
The amount of light from the light source 11 is maximum when facing to the side 2), and the amount of light from the light source 11 is minimum when the light projection windows 32 of the pair of light shields 31 face each other. It is formed so that the intermediate position is the zero point of the pulse motor 36.

7 and 8 show a third embodiment of the present invention, and 39 is a film provided to surround the detection section 6. In FIG. The film 39 is supported by a roller 40 and rotatably provided by a pulse motor 36, and is provided with graded opaque areas, for example, F1 to F5.
1 is the darkest opaque region and F5 is the brightest opaque region, and the pulse motor 36 is formed to have a zero point when the light source is located at F3 in the middle region. The drive control of the pulse motor 36 is similar to the control block diagram shown in FIG.

The operation of this embodiment is also similar to that of the second embodiment 2), and the pulse motor 3
6), when the output voltage decreases, the film 39 rotates in the F+ (bright opaque region) direction and the amount of light from the light source 11 increases.

Effects of the Invention As described above, the present invention provides a second light receiving sensor that detects the amount of light from the light source near the detection section, inputs the detection signal of the second light receiving sensor to a smoothing amplifier and averages it, Since the light source dimmer is activated by the level of the signal voltage output from the smoothing amplifier, when the light intensity of the light source is attenuated due to dust etc. adhering to the detection part, the light intensity of the light source is increased accordingly. However, it is possible to always maintain a constant detection sensitivity, and the selection accuracy does not deteriorate over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view of a color sorter according to an embodiment of the present invention, FIG. 2 is an enlarged view of the same part, and FIG. 3 is a control circuit diagram of an ejector.
Fig. 4 is a circuit diagram of the automatic light control device, Fig. 5 is a partially cutaway perspective view showing the second embodiment of the automatic light control device, and Fig. 7 is a vertical cross section showing the third embodiment of the automatic light control device. 8 are partially cutaway perspective views of the same, and FIG. 6 is a control block diagram in the second and third embodiments. DESCRIPTION OF SYMBOLS 1... Tank, 2... Vibration supply gutter, 3... Excavation device, 4... Chute, 5... Sorting room, 6... Detection part, 7... Ejector, 8...・Precious pipe, 9・
... Colored grain outlet, 10 ... Partition plate, 11 ... Light source, 12 ... Background, 13 Light receiving sensor, 14
...Lens tube, 15...Transparent wall, 16...Second light receiving sensor, 17...Nozzle, 18...Control unit,
19... Operation panel, 20... Power supply unit, 21...
Head amplifier, 22... Main amplifier, 23... Comparator, 24... Monostable multivibrator.
125...OR gate, 26...transistor,
27... Inverting amplifier, 28... Integrating smoothing amplifier, 2
9...Pulse generator, 30...Triac, 31
...Light blocking body, 32...Light projection window, 33, 34.35.
...Gear, 36...Pulse motor-137...A
/D converter, 38...pulse motor drive circuit, 39
...Film, 40...Roller.

Claims (6)

[Claims] (1) A light source near the lower end of the chute through which the grains flow down;
The light receiving sensor detects the amount of light obtained by irradiating the grain particles falling from the chute from the light source and the amount of light from the background. In the color sorter that detects colored particles and operates an ejector by discriminating the colored particles based on the detection signal to sort out the colored particles, a second light receiving sensor for detecting the amount of light from the light source is provided near the detection section, and A color sorter, comprising: a smoothing amplifier that inputs the detection signal of the second light receiving sensor; and a light control device that automatically adjusts the amount of light from the light source according to the output of the smoothing amplifier. Automatic dimmer. (2) Automatic adjustment of the color sorting machine according to claim (1), wherein an amplifier for amplifying the detection signal of the second light receiving sensor is provided between the second light receiving sensor and the smoothing amplifier. light device. (3) The automatic light control device for a color sorter according to claim (1) or (2), wherein the smoothing amplifier is an integral smoothing amplifier. (4) The light control device controls the current of the light source.
Automatic light control device for color sorting machine described in section 3). (5) The light control device is a light shield provided rotatably covering the light source, and the light shield is provided with a light projection window. An automatic light control device for a color sorter according to item 2) or item (3). (6) The light control device is a film that is slidably stretched close to the light source, and the film has a stepwise opaque area formed in the claim (1);
An automatic light control device for a color sorter according to item (2) or item (3).