JPH0243978A - Granular material color sorter - Google Patents

Abstract

PURPOSE:To make it possible to keep a speed of a transporting belt constant by installing a tachometer to measure the rotation speed of a transporting belt and connecting the tachometer electrically to an operation circuit of a motor through a comparator having a setter. CONSTITUTION:A vibrator supplying gutter 8 is installed in the starting end of an endless transporting belt 2, which is set vertically and rotatably by a speed changeable motor 5 and in whose external circumference a lot of projects are implanted and a means to detect defective products and an ejector 24 are installed in the terminal end of the belt. The detecting means is composed of photo receiving parts 13-15 having a plurality of photo receiving sensors in transverse direction to one optical system, a light source, and a background facing to the photo receiving parts. A tachometer 36 to measure the rotation speed of the transporting belt 2 is installed and the tachometer 36 is connected to an operation circuit for the motor 5 electrically through a comparator 37 having a setter 39 between them. As a result, the speed of a transporting belt is kept constant and defective products are surely removed by the ejector.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention aims to identify defective products from among diced vegetables such as carrots, potatoes, or lettuce, or granular materials such as resin pellets or beans that are used as materials for resin molding. This invention relates to a granular material color sorter that sorts granular materials based on differences in hue.

[Conventional technology]

Conventionally, Japanese Patent Publication No. 54-28336 is known as a method of projecting light onto grains and sorting out defective products and foreign substances that do not have a predetermined color based on the amount of reflected light. A system was developed in the 5th year of the Tokugawa Shogunate that evaluated fruits in multiple stages by projecting light onto the epidermis and measuring the amount of reflected light.
It is publicly known as No. 9-26357.

[Problem that the invention seeks to solve]

By the way, in the grain sorting mechanism disclosed in Japanese Patent Publication No. 54-28336, etc., the downflow gutter for arranging grains such as rice grains and supplying them to the detection unit is provided at an angle.
Diced vegetables adhere to the surface of the gutter due to their large amount of moisture, so they do not slide down the drain, and resin pellets are too light to form a consistent falling path, causing beans to bounce up in the gutter. , none of which are suitable for supply by downspout. On the other hand, as is known from Special Publication No. 59-26357,
In devices that feed the materials to be sorted using a belt, a large number of hair-like protrusions are formed on the belt surface to prevent diced vegetables from adhering to the belt surface, and the belt is always placed in a predetermined direction from the end of conveyance toward the detection and sorting section. Draw a falling path and have it supplied.

However, even when conveying by a belt, the speed of the belt changes due to slippage between the belt and pulley or changes in the rotation speed of the motor due to voltage drop, etc., and as a result, the objects to be sorted are released from the end of the belt and fall. Since the path taken by the ejector is different from the predetermined falling path, the image formation state of the light receiving sensor changes in the detection section, resulting in a sorting failure (impossible), and in the sorting and removal section, the positional relationship between the objects to be sorted and the ejector is shifted, resulting in failure. Not only is it not possible to reliably remove good products, but also good products may be removed. In addition, depending on the size and specific gravity of the objects to be sorted, the supply condition (falling route)
Since the belt speed is different, it is necessary to adjust the belt speed to the optimum speed every time the object to be sorted changes.

In view of these points, the present invention makes it possible to easily change the speed of the conveyor belt to the optimum speed for the objects to be sorted when different objects to be sorted are to be sorted continuously, and also to change this optimum speed. It is an object of the present invention to provide a color sorting machine for granular materials that can prevent a decrease in sorting accuracy due to the above-mentioned problems.

[Means for solving problems]

In order to solve the above-mentioned problems, the granular material color sorter of the present invention is provided with a granular material color sorter that is installed horizontally so as to be rotatable by a variable-speed motor, and has a starting end side of an endless conveyor belt that has a large number of hair-like protrusions implanted on its outer peripheral surface. A vibration supply gutter is provided at the end thereof, and a defective product detection means and an ejector are provided at the end thereof, and the detection means includes a light receiving section having a plurality of light receiving sensors in the transverse direction with respect to one optical system, a light source, and the above-mentioned. In a particulate color sorter that has a background facing the light-receiving part,
A technical measure is taken in which a tachometer is installed for measuring the rotational speed of the conveyor belt, and the tachometer is electrically connected to the drive circuit of the motor via a comparator equipped with a setting device. Ta.

Further, it is preferable that the setting device is provided with a switch for setting in advance the optimal belt speed for a plurality of types of objects to be sorted, and for switching these set values.

[Action and effect]

The granular raw material fed into the vibrating supply gutter is supplied to the conveyor belt in appropriate amounts by the vibration of the vibrating feed gutter. The granules that have been conveyed by the conveyor belt and have reached the terminal end draw a predetermined falling path and fall between the light receiving part and the background, and as they are projected from the light source, the light receiving part detects all the falling granules. The amount of reflected light from an object is detected, and if the difference between this amount of reflected light and the amount of light received from the background exceeds a certain level, it is determined to be defective, and is removed by an ejector and sorted. When the speed of the conveyor belt changes due to a slip or a change in the rotation speed of the motor due to some reason, a signal from the comparator is output to the drive circuit to change the rotation speed of the motor and change the setting value of the setting device. In other words, it is matched to the optimum belt speed. As a result, the speed of the conveyor belt is always kept constant, so the particulate matter discharged from the end of the conveyor belt toward the detection means and ejector also follows a constant falling path from beginning to end. The objects to be sorted are always clearly imaged, and the ejector accurately removes defective items.

When the material to be sorted changes, the setting value is changed by changing the switch on the setting device, and the belt speed is changed to the optimal belt speed for the material to be sorted, which has been set in advance. However, it is easy to continue sorting out different types of particulate matter.

(Embodiments of the Invention) Hereinafter, preferred embodiments of the present invention will be described with reference to FIGS. 1 to 5, particularly regarding diced vegetables. In FIG. 1, an endless conveyor belt 2 made of a timing belt or the like is rotatably suspended near the center of an approximately rectangular parallelepiped machine frame 1 placed horizontally.

That is, the conveyor belt 2, which is passed between rollers 3 and 4 that are horizontally arranged in parallel, is rotated at a constant speed by a variable speed motor 5 that is connected to the rollers 3 by a belt or the like. The surface layer of the conveyor belt is made of a material harmless to food, such as urethane rubber, and a large number of trichomes 6 made of the same urethane rubber are implanted on the surface. In addition, side walls 7 are fixedly installed on both sides of the upper surface (transport surface) of the conveyor belt 2 perpendicular to the conveyance direction to prevent cubed vegetables from falling off during conveyance. The trichomes 6 are also implanted.

The leading end of the vibrating supply gutter 8 serving as a means for supplying an appropriate amount is exposed to the starting end side of the m-feeding belt 2. The lower end of the supply hopper 〇 is faced above the vibrating supply trough 8, the bottom surface of the photographing supply trough 8 is supported by a vibrating device 10, and a vibrator 32 is attached to the lower part of the supply hopper 〇.

In addition, trichomes 3 are also provided on the gutter bottom and inner wall surface of the vibration supply FA8.
Plant a large number of 1. This trichome 31 also has the tip trichome 6.
Similarly, it is made of urethane rubber or the like.

On the conveying surface of the conveying belt 2, there is a rotary protrusion 3 as an adhesion-resolving device for loosening cubed vegetables that have adhered to each other.
3 is horizontally installed so as to be rotatable in conjunction with a motor 5. Like the trichomes 6.31, these projections are made of flexible urethane rubber, etc., and are planted in a staggered manner on the cylindrical boss at intervals of about one side of the diced vegetables. is rotated in the direction of returning to the vibration feeder 8 side. Further, a tachometer 36 is attached to the roller 4 on the passive side, and this tachometer 36 is connected to a motor drive circuit 38 via a comparator 37 (see Fig. 3). A speed regulator (not shown) is provided. Furthermore, a setting device 39, a changeover switch 40, and an alarm device 41 are connected to the comparator 37.

On the other hand, defective product detection means is provided midway through the fall path of the diced vegetables discharged from the terminal end of the conveyor belt 2.

That is, a pair of optical cases 11 and 12 are provided facing each other with a length approximately equal to the width of the conveyor belt 2 with the falling path in between, and a light receiving section 13 and a light receiving section 14 are provided in the optical case 11. They are arranged side by side and shifted in the direction of the falling path, and a light receiving section 15 is provided inside the optical case 12. Each of the light receiving sections 13 to 15 has one optical system (sometimes consisting of multiple lenses) 16, and a sensor box behind it has five optical systems.
Two light receiving sensors 178 to 17e (photodiode array) are provided. Then, the background 18 facing the light receiving section 15 in the optical case 12 is placed in the optical case 1.
1, and the light receiving section 13.14 inside the optical case 11 is
The background 19 relative to the light receiving unit 13 is designed to intersect with the detection lines P of the diced vegetables along the falling path.
A background 20 for the light receiving section 14 is provided in the optical case 12. That is, the light receiving section 13 and the light receiving section 14 are provided facing inward to each other, and from the detection line P, each light receiving section 13 to
15 are set at equal distances, and each optical system 16 is arranged so that the diced vegetables on the detection line P form an image on the light receiving sensors 178 to 17d through a slit (not shown) in front of the optical system 16. provided. In addition, each light receiving section 13 to 15
are arranged in series in the width direction of the conveyor belt 2 in the optical case 11.12, and almost all of the diced vegetables on the detection line P are detected by the light receiving sensors 17a to 17e of the respective light receiving sections 13 to 15. It will capture the circumferential surface (see Figure 5).

Fluorescent tubes 21A-21E are arranged within each optical case 11.12. That is, inside the optical case 11 is a fluorescent tube 21A that illuminates the vicinity of the detection line P through the transparent plate 22 of the optical case 11.

21C are provided along the light receiving sections 13 and 14, respectively, and a fluorescent tube 2 which also serves as a light source for the background 18 is provided.
1B, and a transparent plate 2 is provided inside the optical case 12.
Fluorescent tubes 21D and 21E are provided with the light receiving section 15 in between and serve as a light source for illuminating the vicinity of the detection line P through the fluorescent tube 3 and as a light source for the background 19.20.

Each of the backgrounds 18 to 20 is rotatably provided by a servo motor or the like (not shown) via a microcomputer so that the angle with respect to the fluorescent tubes 21B, 210, and 21E provided nearby can be changed. The brightness of background rounds 18 to 20 is automatically adjusted according to the object to be sorted.

Near the fall path below the detection line P, there are light receiving units 13 to 13.
An ejector 24 is provided in correspondence with each of the 15 light receiving sensors 178 to 17e.

The ejector 24 is connected to an air compressor (not shown), and the light receiving sensors 178 to 17e and the light receiving sensors 17a to 1
The operating circuit of the electromagnetic valve 25 in the ejector 24 corresponding to 7e is electrically connected. In addition, a good product discharge gutter 2 is located below the ejector 24, that is, on the falling path.
6, and a defective product discharge gutter 27 is provided on one side of the non-defective product discharge gutter 26 to receive the defective products blown away by the ejector 24, and a regulating valve 28 is provided at the branching part of the defective product discharge gutter 27.

In addition, a gutter 3 is located directly below the conveyance end of the conveyor belt 2 to receive water.
4 will be provided. That is, the upper end is provided directly below the terminal end of the conveyor belt 2, and the lower end is inclined toward the starting end of the conveyor belt 2, which is the side opposite to the optical case 11.12, and a water reservoir 35 is provided at the lower end. Connect.

Next, specific operations in the above embodiment will be explained. Put diced carrots, which are one of the diced vegetables, into the supply hopper 9, set the changeover switches 40 of the three setting devices to the "carrot" side, and then turn on the vibrator 32 of the supply hopper 9 and the vibrating supply gutter 8. When the vibration device 10 and motor 6 are started, carrots are cut into cubes (hereinafter simply "
Carrots (referred to as "carrots") are supplied onto the conveyor belt 2 in appropriate amounts by a vibrating supply gutter 8. That is, the carrots that have flowed down onto the net 30 of the vibrating supply gutter 8 are supported by the tips of the trichomes 31 and are conveyed toward the end of the machine, but the contact area between the carrots and the trichomes 31 is Because it is extremely small,
Carrots do not stick to the conveying surface, and excess water on the carrot surface falls to the bottom of the trichomes 31 and does not stick to the carrots again. ). Furthermore, the trichomes 31 installed on the four walls of the vibrating supply gutter 8 prevent carrots from adhering to the four walls, and the vibrator of the supply hopper 9 prevents carrots from adhering to the interior of the supply hopper 9. It is supplied smoothly without leaving any residue.

The carrots supplied onto the conveyor belt 2 are conveyed while being supported by the tips of the trichomes 6, and then the carrots are conveyed onto the conveyor belt 2.
When reaching the terminal end, the rotating protrusions 33 provided on the conveying surface of the conveyor belt 2 cause carrots that stick to two or more in a row to be bounced back by the flexible protrusions. Separate and fall apart. The conveyor belt 2 moves at a speed set by the changeover switch 40, that is, about 1.5 m/s, which is the optimal speed for carrots set in advance.
The carrots at the end of the conveyance are easily detached from the trichomes 6 and released one after another as the trichomes 6 rotate along the roller 4, and the carrots at the end of the conveyance are released along the falling path in the figure. As shown, it falls between a pair of optical cases 11 and 12. When carrots are transported and supplied in this way, if the conveyor belt 2 and pulley 3.4 slip, or if the rotation speed of the motor 5 decreases due to voltage drop, etc., the tachometer 36 The signal value and the signal value of the setting device 39 become inconsistent. If this difference exceeds the permissible range, the rotation speed of the motor 5 is increased by an output signal from the comparator 37 to the drive circuit 38, and the difference between the two signal values is brought within the permissible range. Note that when this difference exceeds a certain level, a red light or a buzzer serving as the alarm device 41 may be activated, and the motor 5 may be stopped at the same time. Further, the tachometer 36 may be of any type, and the tachometer 36 may be mounted so as to slide on the back surface of the belt (see the two-dot chain line in FIG. 1).

The carrots falling between the pair of optical cases 11 and 12 are oriented in various directions, but when these carrots pass the detection line P, defective products are detected by the light receiving sections 13 to 15. That is, the light receiving sections 13 and 14 and the light receiving section 1
5 and 13.1 across the belt-shaped falling path, and the light receiving section 13.1.
4 is shifted in the flow direction of the carrots and is provided toward the detection line P, so when the carrot passes through the detection line P, almost the entire surface of the carrot is captured from three directions.On the other hand, the light receiving sections 13 to 15 Fluorescent tubes 21A to 21E are arranged near each of the fluorescent tubes 21A to 21E, so that the entire surface of the carrot is projected. Each of the light receiving sensors 178 to 17e of the light receiving sections 13 to 15 receives the amount of light from the opposing backgrounds 18 to 20, respectively. When reaching the detection line P, one or more of the light receiving sensors 178 to 17e of the light receiving sections 13 to 15 facing this surface detects the background light 18 to 19, which has been adjusted to have approximately the same light intensity as that of a normal carrot. Detects the difference in light amount between the light amount and the defective surface. This difference is electrically converted and compared with a preset threshold. If the signal (voltage) is larger than the threshold, the carrot is determined to be defective, and the position of the light receiving sensors 17a to 17e is determined. The ejector 24 corresponding to the ejector 24 operates with a slight delay (the carrot on the detection line P is delayed by the time required for it to fall to the injection port of the ejector 24), and the carrot is sprayed into the defective product discharge gutter 27.

The light intensity of the backgrounds 18 to 20 can be adjusted by changing the angle of the backgrounds 18 to 20 and raising or lowering the light intensity using a microcomputer or the like to the light receiving sensors 17a to 17.
．． The brightness that makes the output waveform of e is the smallest is selected, and it works to always match the light amount of backgrounds 18 to 20 with the light amount of normal carrots, which account for the majority of raw carrots.

Carrots are released from the end of the conveyor belt 2 along a predetermined falling path, but the water accumulated at the bottom of the conveyor belt 2 drips from the end, and this water is guided to the water receiving gutter 34. The water is collected in the water reservoir 35.

Carrots are sorted in this way, but when sorting resin pellets subsequently, switch 4
Set 0 to 1 resin beret and start operation. The speed of the conveyor belt 2 in this case is, for example, 2.0 m.
/sec, and the resin pellets are lighter than carrots.
It is set in advance so that it is supplied along a predetermined falling path.

Note that the opposing transparent wall 22.2 of the optical case 11.12
3 may be provided with a wiper 29 for removing dust etc. adhering to the transparent walls 22, 23. Further, the present invention is not limited to this embodiment, and the present invention is not limited to this embodiment, and includes a method of receiving light amounts divided into a plurality of wavelength bands using separate light receiving sensors.
It goes without saying that a so-called bichromatic type can also be used, and the protrusions are not limited to hair-like ones, but may be of any shape that makes the contact surface between the surface to which diced vegetables or the like tend to adhere smaller and the conveying surface smaller.

[Brief explanation of the drawing]

Figure 1 is a side view and central vertical cross-sectional view, Figure 2 is a partially enlarged view of Figure 1, Figure 3 is a control block diagram, and Figure 4 shows the relationship between falling objects to be sorted and a pair of optical cases. The perspective view shown in FIG. 5 is an explanatory diagram of the light receiving section. DESCRIPTION OF SYMBOLS 1... Machine frame, 2... Conveyor belt, 3... Roller 4... Roller 5... Motor, 6... Ciliary projection, 7... Side wall, 8... Vibration supply Gutter, 9... Supply hopper 10... Vibration device, 11.12... Optical case, 13-15... Light receiving section, 16... Optical system, 1
7a-17e...Light receiving sensor, 18, 19.20.
...Background, 21A-21E...fluorescent tubes,
22゜23...Transparent plate, 24...Ejector, 2
5... Solenoid valve, 26... Good product discharge gutter, 27... Defective product discharge gutter, 28... Adjustment valve, 29... Wiper
31... trichome, 32... vibrator-133
... Rotating protrusion, 34 ... Water receiver is gutter, 35 ... Water reservoir, 36 ... Tachometer, 37 ... Comparator, 3
8... Drive circuit, 39... Setting device, 40... Changeover switch, 41... Alarm device.

Claims (2)

[Claims] (1) A vibrating supply gutter is installed at the starting end of an endless conveyor belt that is horizontally installed so that it can be rotated by a variable speed motor and has many protrusions planted on the outer circumferential surface, and a vibration supply gutter is installed at the end end of the endless conveyor belt. A granular material comprising a detection means and an ejector, each of which is provided with a light receiving section having a plurality of light receiving sensors in a direction transverse to one optical system, a light source, and a background facing the light receiving section. The color sorter is equipped with a tachometer for measuring the rotational speed of the conveyor belt, and the tachometer is electrically connected to the drive circuit of the motor via a comparator equipped with a setting device. Features: Color sorting machine for granular materials. (2) The granular material color sorting machine according to claim 1, wherein the setting device is provided with a switch that presets an optimum belt speed for the material to be sorted and changes these set values.