JPH042315B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mechanism for sorting particles, such as rice grains, by light, and aims to improve the accuracy of sorting with a simple configuration and to reduce the impact given to particles during sorting. .

Industrial Application Field The present invention is a device for sorting particulate materials produced or distributed in various industries, such as rice and beans in agriculture, balls and buttons in industry, based on their optical characteristics such as brightness and color. Use it for.

Conventional technology There is a conventional sorting device of this type that uses a downflow gutter and performs sorting by air injection.
16031, Special Publication Showa 54-28336). As pointed out in Japanese Patent Application Laid-Open No. 57-113879, it is customary for these blast sorting devices to blow away and sort out unusually colored grains using a bundle of air ejected from their jet nozzles. Since the width of the tip of the air flux is not sharp, particles other than the target are blown away along with them, resulting in a decrease in sorting accuracy.

In addition, a device for sorting out abnormal grains with a pick-up stick (Japanese Patent Laid-Open No.
55-106576), a device for separating and sorting by colliding impact fragments with foreign objects (Japanese Patent Application Laid-open No. 58-84085), and a device for displacing defective grains that can freely protrude upward from between a large number of linear bodies. (Utility Model No. 57-47283) etc. have been proposed.

Problems to be Solved by the Invention (1) A sorting device should be configured as simply as possible to facilitate production.

In addition to the nozzle, the blast sorting device requires an air compressor, a drain removal device, etc., making the device complicated, large, and expensive. It is necessary to have a simple configuration, so that processing and assembly are easy, and adjustment does not require much effort.

(2) The mechanism must be able to accurately and reliably sort out optically determined particles such as different colored particles.

In devices that use extraction rods and impact pieces, it is necessary to use a delay circuit to synchronize the timing of the extraction rods and impact pieces to hit different-colored grains, etc., and the difference in the falling speed of the particles can affect the sorting accuracy. is possible.

(3) Since the particles are sorted as they move in a state close to natural fall, it is unavoidable that the particles will be subject to shocks that cause sudden changes in the moving speed of the particles when moving on to the next step after sorting. We want to avoid colliding with particles.

Structure of the Invention In order to solve the above-mentioned problem (problem), a path for particles is provided on the slope so that particles can be optically distinguished one by one and mechanically sorted. Examples will be described with reference to the drawings.

A solenoid 4 vibrates a receiving device 3 for particles 2 supplied from a hopper 1 so that the particles 2 slide (roll) down an inclined path, such as a downflow gutter or a slope 5. As illustrated in FIG. 2, the slope 5 is provided with filaments 6 to create passages 7 for a plurality of particles. The thickness of the filament 6 (defining the height from the slope) is such that the particle 2 cannot easily overcome the filament 6 when moving on the slope 5. When the particles 2 slide down the slope 5, the direction of the particles 2 is regulated by the filaments 6. The filaments 6 are made to intersect at the top of the slope, and at the bottom of the slope 5, the width of the particle passage 7 is narrowed to such an extent that it does not become an obstacle when the particles 2 slide down in a line, so that the particles 2 can be arranged at arbitrary intervals. They slide down the multiple passages 7 in a line.

The particle passage 7 as described above can be made by resin molding so that the filaments 6 are embossed on the surface of a plate of synthetic resin, for example, polycarbonate.
In this case, the portions of the filament 6 other than those on the passage 7 side do not play any functional role, so they may have any shape.

Particle 2 is illuminated with light source 8 or light source 9, and particle 2
The light reflected or transmitted through the lens 10 is received by the photodetector 11, and the light information (brightness or transparency) is converted into an electrical signal. Since each particle 2 in a plurality of particle rows is optically discriminated one by one, one lens (set) 10 may be attached to each photodetector 11 provided for each particle row. However, as illustrated in FIG. 3, if the light reflected or transmitted by a plurality of particles 2 is received by a plurality of photodetectors 11 via a lens 10, the entire device employing the present mechanism can be placed in a narrow space. It is practical because it is easy to put together. lens 10
The space between the lens 10 and the photodetector 11 is a dark room 12, and a suitable light shielding plate 13 is provided around the area between the lens 10 and the particle 2.
to prevent unnecessary light from entering.

The electric signal obtained by the photodetector 11 is amplified and compared with a separately generated comparison signal to obtain a signal for distinguishing between standard particles and non-standard particles, and the signal is passed through a monostable multivibrator capable of retriggering operation.
This signal is power amplified and passed to the solenoid 14,
By moving the repelling piece 15, the particles 2 within the standard or the particles 16 outside the standard are sorted out.

A block diagram illustrating the processing of the signal obtained by the photodetector 11 is shown in FIG. 4, but circuits not shown in this diagram, such as temperature compensation, operation display, or inspection circuits (devices) can be added. .

The repulsion piece is provided so that it can be moved by a solenoid at a position where it is hit by particles falling in a row. When the particles 2 sliding down the slope 5 hit the repelling piece 15, they bounce.The traveling direction of the particles 2 after bouncing is regulated by the installation angle of the repelling piece 15.The repelling piece 15 is moved by the connected solenoid 14, When the particles 2 are prevented from hitting the repelling piece 15, the particles 2 travel almost straight.By providing the partition plate 17, the particles are sorted so that the particles 16 are within the standard or outside the standard depending on the direction of movement of the particles 2. Ru. A spring 18 and a stopper 19 are attached to the repulsion piece 15 so that a steady position can be determined. As illustrated in Figure 5,
A flat portion can be provided at the tip of the movable core 20 of the solenoid 14 to serve the same role as the repulsion piece 15.

By configuring the present mechanism in two or more stages, it is possible to successively perform sorting based on the amount of light reflected by the particles and/or sorting based on the amount of light transmitted through the particles.

Effects of the Invention (1) Since the slope is provided with striations to form a path for particles so that a plurality of rows of particles are formed, it becomes easy to optically identify particles one by one.

(2) Since the repulsion piece is configured with a spring and a stopper attached to the repulsion piece so as to be in a steady position, the mechanism is simple and easy to manufacture.

The movable iron core of a solenoid has inertia.
When an electrical signal to move the repelling particles is passed through the solenoid, the direction of the particles does not change immediately, but there is a delay for a certain period of time. This eliminates the need for a delay circuit even if the position of the repellent piece is shifted from the position where particles are detected by light, simplifying the mechanism and saving time and effort for adjustment.
By adjusting the spacing between the falling particles and installing the partition plate at an appropriate position, particles can be sorted efficiently and accurately.

(3) Taking advantage of the fact that the waveform of the electrical signal obtained by a photodetector changes depending on whether the light is reflected by the particles or the light transmitted by the particles, for example, in the case of rice, ``Shirata-Nuki'' is used. Sorting is done by light, which is called ``Uruchi-nuki''. In some cases, such as when processing kuzumai (immature rice), good rice is selected from among the kuzumai. In this case, in the present mechanism, the waste rice bounces on the repelling pieces located at a steady position, but the selected good rice can be configured so that it does not hit the repelling pieces during sorting.
Damage to good rice can be reduced.

(4) By configuring the present mechanism in two or more stages, for example, polished rice grains can be consistently and simultaneously classified into burnt rice, shirataki rice, non-glutinous rice, etc.

[Brief explanation of drawings]

The figure shows an embodiment of the invention. Fig. 1 is a side view with a part cut away, Fig. 2 is a front view of the slope, Fig. 3 is a schematic diagram of the optical path, Fig. 4 is a block diagram of signal processing, and Fig. 5 is a simple example. One part is shown in a side view. 1...Hopper, 2...Particle, 3...Receiver,
4, 14... Solenoid, 5... Slanted surface, 6... Line, 7... Particle passage, 8, 9... Light source, 10...
...Lens, 11...Light sensor, 12...Darkroom, 1
3... Light-shielding plate, 15... Repulsion piece, 16... In-standard particles or non-standard particles, 17... Partition plate, 18...
... Spring, 19 ... Stopper, 20 ... Movable iron core, 21 ... Signal amplifier, 22 ... Comparison signal generator, 23 ... Comparator, 24 ... Monostable multivibrator capable of retrigger operation, 25 ... Power amplifier.

Claims (1)

[Claims] 1. In a device that sorts particles by illuminating particles falling through an inclined path with a light source and detecting the amount of light reflected or transmitted by the particles,
A repelling piece that repulses falling particles on the top surface to change the direction of movement of the particles, a spring that biases the repelling piece to press it against a stopper, and an electric signal to sort out the particles to apply the biasing force of the spring to the repelling piece. 1. An optical particle sorting mechanism characterized by having a solenoid that moves in a direction crossing the falling direction of particles and a partition to sort out particles.