JPS6327649B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic weight sorting device suitable for use in a fruit sorting system for sorting fruits by weight.

In an automatic weight sorting device used in a conventional fruit sorting system, a plurality of classification sections are arranged along a conveyor, and each of these classification sections is equipped with a weighing device, a classification device, and a receiving box. Each time the fruit passes through the cup, the load is measured by a weighing device. If the weight of the fruit is light compared to the set weight of the weighing device, it is allowed to pass through as it is, and if it is heavy, the sorting device is activated to tilt the cup and remove the fruit from above the cup. It was constructed so that it would be dropped and stored in a receiving box.

However, such conventional automatic weight sorting equipment requires as many weighing devices as there are classification sections, making the equipment larger and heavier, increasing equipment costs, and requiring numerous adjustments to the set weight for classification. Adjustment work becomes extremely troublesome because adjustment is performed for each weighing device. In addition, since a mechanical weighing device is used, there is a limit to the accuracy of weighing, and the measuring capacity has many drawbacks, such as the ability to obtain only about 1,500 pieces per minute.

This invention was made to eliminate these conventional drawbacks, and its purpose is to:
All cup loads can be measured with one weighing device,
Moreover, it is an object of the present invention to provide an automatic weight sorting device that can accurately classify objects to be sorted into predetermined classification locations.

In order to achieve such an object, the present invention uses a weighing device to measure the cup load of all empty cups in a passageway in which a plurality of cups carrying objects to be sorted are arranged at equal intervals and conveyed. When the empty cup signal is stored, the previous content is updated according to the cup number, and when the cup load of the cup on which the object to be sorted is placed is measured, it is stored from the placed cup signal. According to the weight value of the object to be sorted obtained by subtracting the empty cup signal of the cup in the cup, a classification signal is sent out at the timing when the measured cup reaches a predetermined classification device, and the weight of the object is automatically divided into classes. It is designed to sort out the things to be sorted.

Hereinafter, this invention will be explained in detail based on examples.

FIG. 1 is a plan view of an embodiment of an automatic weight sorting device according to the present invention. In the figure, 1 is a plurality of cups attached to an endless chain (not shown in FIG. 1) in a continuous array at regular intervals, 2 is a drive unit consisting of a sprocket, a motor, etc. that drives the chain, and 3 is a drive unit that drives the chain. a driven part consisting of a sprocket, etc. that supports the chain at a position opposite to the driving part 2;
4 is a plurality of receiving boxes arranged along the chain for each weight class; 5 is a chute for receiving box 4; 6 is a receiving box for each weight class;
Reference numeral 1 indicates a classifying device provided at each position of each receiving box 4 in the cup transport path, 7 a weighing device provided in the cup transport path in front of the frontmost receiving box 4, and 8 a base of the weighing device 7. Therefore, all the classifying devices 6 are arranged behind the weighing device 7. Note that the chain, the driving section 2, and the driven section 3 constitute a conveyor means. Here, when the driving section 2 operates, the cup 1 is conveyed in the direction of the arrow, turns downward at the driving section 2, and turns upward again at the driven section 3. When a fruit to be sorted is placed on the cup 1 at a placement point A near the driven part 3, the weight of the fruit is measured by the weighing device 7 while it is still placed on the cup 1. . This measured value is processed by a data processing device to be described later, and the position of the classifying device 6 in the receiving box 4 to be classified is determined based on the measured weight of the fruit. And 1 cup with this fruit on it
is transported to the predetermined position of the classification device 6, the data processing device transfers the data to the classification device 6.
A classification command signal is sent. As a result, the sorting device 6 is operated, the cup 1 is tilted toward the receiving box 4, and the fruit falls into the receiving box 4 and is sorted.

FIG. 2 is a side view of the measuring device 7, and FIG. 3 is a front view of its internal structure. In the figure, 10 is the fruit placed on the cup 1, and 11 is the fruit placed on the cup 1.
A cup support device is supported so that it can be rotated and tilted to the left in FIG. 15 is a mounting member for attaching the cup support device 11 to the chains 13 and 14; 16 and 17 are the chains 1;
18 is a pin rail for supporting the sliding pin 12 provided along the chain 13, and 19 is a conveyor support frame. The pin rail 18 has only a portion of the measuring device 7 removed, and a guide rail 71 of the measuring device 7 is fixed to this portion in parallel with the pin rail 18. A weighing rail 72 is arranged parallel to the guide rail 71. As shown in FIG. 3, the guide rail 71 fixed to the top surface of the weighing device has an elongated hole 71a formed along the longitudinal direction, and has a front side (left side in the figure) and a rear side (left side in the figure) in the center of the top surface. Recesses 71 each having an inclined surface (on the right)
b is formed. The weighing rail 72 is disposed in the elongated hole 71a facing the recess 71b. In addition, 73 is a weighing table fixed to the center part of the lower surface of the weighing rail 72, and 74 is this weighing table 73.
75 is a diaphragm type load cell consisting of a mechanical/electric transducer such as a piezoelectric element that supports the lower surface of the weighing platform 73, and 76 is a cell base that supports the load cell 75. The base 77 is a screw for adjusting the vertical position of the cell base 76.

The cup support device 11 is
Since it is supported via a point-parallel link mechanism,
You can move up and down while maintaining your posture. Therefore, when the cup 1 is conveyed in the direction of the arrow and the sliding pin 12 rides on the weighing rail 72 from the front (left) pin rail 18 via the guide rail 71, the fruit 10, the cup 1, and the cup support device 11, the entire load of the sliding pin 12, etc. is applied to this weighing rail 72. The initial load of the weighing rail 72, weighing platform 73, etc. is always applied to the load cell 75, but when the cup 1 passes over the weighing rail 72, the above-mentioned total load is further applied, and the load cell 75 receives the load according to its characteristics. A voltage proportional to the load is output.

FIG. 3 is a front view of the classification device 6. In the figure, reference numeral 20 denotes a classification recess formed in the pin rail 18 within the range of the receiving box 4 and having a longitudinal inclination;
1 is a classification rail provided at the front end of the classification recess 20 so as to be rotatable downward about a support shaft 22, 23 is a cam that moves the classification rail 21 up and down, 24 is a rotary solenoid that rotates the cam 23, and 25 is a classification rail. A classification auxiliary rail 27 is provided at the rear end of the recess 20 so as to be rotatable upward about a support shaft 26.
This is an auxiliary rail installed above the here,
When the rotary solenoid 24 is not operating, the classification rail 21 is in a horizontal position parallel to the pin rail 18, so the sliding pin 12 moves from the classification rail 21 over the auxiliary rail 27, and the cup 1 is tilted. do not. However, when the rotary solenoid 24 is operated in response to the classification command signal, the classification rail 21 takes an inclined position due to the rotation of the cam 23, so the sliding pin 12 moves from the classification rail 21 through the classification recess 20. . As a result, the supporting position of the sliding pin 12 is lowered, so the cup supporting device 11b is lowered, the cup 1 is tilted, and the fruit 1 is lowered.
0 falls into the receiving box 4. When the sliding pin 12 reaches the rear end of the classification recess 20, the classification auxiliary rail 2
5 and return to the top of the pin rail 18. After passing the sliding pin 12, the classification auxiliary rail 25 returns to its original horizontal position due to its own weight. Therefore, when a cup carrying fruit to be sorted in a certain receiving box reaches the sorting rail of this receiving box, the data processing device sends a sorting command signal to the rotary solenoid to tilt the sorting rail. When transmitted, the fruit falls into a receiving box and is sorted.

FIG. 5 is an explanatory view of the reference detection means for designating the cup number, with A showing a front view and B showing a side view. Reference numeral 28 designates a detection portion extending downward and fixed to the lower part of the attachment member 15 of a specific one of the cups 1, and 29 designates a photoelectric switch formed in a U-shape. The photoelectric switch 29 consists of a light emitter and a light receiver that receives the light projected from the light emitter, and when the detector 28 passes between them, the light is blocked, so the photoelectric switch 29 sends out a detection signal. This photoelectric switch 29 is placed immediately before the metering device 7.

FIG. 6 is a block diagram of the control circuit. The electric signal corresponding to the load value output from the load cell of the weighing device 7 is amplified by the amplifying section 31 and passed through the filter 3.
After the noise is removed in step 2 and converted into a digital signal by the A/D converter 33, the signal is sent to the sampling circuit 3.
Enter 4. Note that 35 is an A/D converter control device for controlling the A/D converter 33. The electrical signal output from the load cell has the shape of a rectangular wave with the time width of the sliding pin passing over the weighing rail, but the peak value of the wave changes depending on the time during the time span, so there is only one point. Instead of measuring just one point, several points are sampled and measured, and the sample value averaging circuit 36 calculates the average value. This average value output is input to a comparison/judgment circuit 37 to judge whether there is fruit on the cup. The standard setting device 38 stores in advance a standard setting value, which is the maximum value of the empty cup load, that is, the tare weight, plus a certain value, and the average value output input to the comparison judgment circuit 37 is compared with this standard setting value. be done. The average value output is smaller than the reference set value when no fruit is placed, and is determined to be fruitless, and is inputted to the storage device 39 as an empty cup signal, and is larger than the reference set value when fruit is placed. It is determined that there is fruit, and the fruit is inputted to the fruit data processing device 40 as a placement cup signal.

On the other hand, the number recognition circuit 41 receives the electric signal from the weighing device 7 and the detection signal from the photoelectric switch 29, and identifies the cup that passes through the weighing device 7 and is measured immediately after the detection signal is input as, for example, the No. 1 cup. It recognizes the cup, sends an address designation signal to the storage device 39, counts the electric signal output every time the cup passes the measuring device 7, and sequentially recognizes the second cup, the third cup, and so on. and sends an addressing signal. Then, when the first cup is measured, no fruit is placed on it and an empty cup signal is input to the storage device 39. The corresponding address is designated and the empty cup signal is read and stored in the storage element at that address. At this time, the previously stored content is updated with new content.

When the second cup is measured, a fruit is placed on the fruit, and when the placed cup signal is input to the subtraction circuit 42 of the fruit data processing device 40, the address designation signal input to the storage device 39 at the same time is Therefore, the address corresponding to the second cup is specified,
The empty cup signal of the second cup already stored in the storage element at this address is read out and sent to the subtraction circuit 42. At this time, the same data is rewritten so that the empty cup signal of the second cup does not disappear from the storage device 39.

In the subtraction circuit 42, the empty cup signal of the second cup is subtracted from the placed cup signal of the second cup, and a weighing signal corresponding to the fruit weight is calculated. This weighing signal is converted into a gram value in a gram conversion circuit 43, and further compared with a classification value preset in a class weight division value circuit 45 in a class determination circuit 44. As a result, the position where the fruit should be classified is determined, and a classification command signal is input and latched into the preset counter 46 corresponding to the measured fruit classification value. The preset counter 46 receives the electrical signal pulses output from the measuring device 7 every time one cup passes, and counts the number of pulses. When the cup carrying the measured fruit is transported to the position where it is to be classified, the preset counter 46 counts a predetermined number of pulses and sends a classification command signal to the classification device 6 placed at that position. do. In this way, the fruit is placed in a receiving box with a class weight classification value corresponding to its weight.

In such a configuration, if the conveyor is run once with empty cups before starting the fruit sorting process,
The load outputs of all the cups are input to the storage device 39 as empty cup signals, and the previous contents are updated and stored in the address corresponding to the cup number.

Then, when the fruit sorting operation is started, each loaded cup signal is subtracted by the empty cup signal of that cup number, and the weight value of only the fruit is calculated. Since empty cups may occur during fruit sorting due to omission of placement, etc., the empty cup signal is updated to the latest value by these empty cups. Generally, the loading rate is 80 to 90%, so 10 to 20% of empty cups occur randomly every round, and the empty cup signals of these cups are updated sequentially. Therefore, after many rounds, the initial empty cup signal for almost all cups will be updated.

In this device, the cup load, or tare weight, of empty cups is sequentially updated and stored before and during the fruit sorting process, and the tare weight is subtracted from the total weight of the placed cup, so that only the fruit can be stored. Weight is measured accurately. There is also a method of measuring the average tare weight of empty cups in advance and subtracting this value from the weight of all placed cups, but this method will reduce the variation in the weight of empty cups (about ±2g even immediately after production). Errors occur due to influence.
In addition, the sensitivity of the load cell and the degree of amplification of the amplifier vary depending on temperature drift, and for example, the output value will be larger when the temperature is high in the afternoon than when the temperature is low in the morning. An error will occur. Furthermore, the tare weight of an empty cup may fluctuate if mud gets on the cup or if water soaks into the sponge provided on the cup for cushioning, causing errors. However, if you update the content of the empty cup signal in the storage device by making one round before starting work, as with this device, when you measure the weight of the placed cup, you can subtract the latest tare weight of that cup. The weight of the placed fruit is measured, and the effects of these errors are all removed, resulting in a highly accurate measurement value.

In addition, since this device can measure all cup loads with one weighing device, the device is compact, equipment costs are reduced, and adjustment work for the weighing device is also simplified. In addition, since the weighing device measures electronically, the weighing speed is faster and the accuracy is higher.
The processing capacity is more than twice that of the conventional one.

As described above, according to the automatic weight sorting device of the present invention, the weighing accuracy of the objects to be sorted is increased, so that accurate weight classification is possible and the sorting work efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a plan view of an embodiment of the automatic weight sorting device according to the present invention, FIG. 2 is a side view of the weighing device, FIG. 3 is a front view of its internal structure, and FIG. 4 is a front view of the classification device. FIG. 5 is an explanatory diagram of the reference detection means, and FIG. 6 is a block diagram of the control circuit. 1... Cup, 2... Drive section, 3... Driven section,
4... Receiving box, 6... Classifying device, 7... Weighing device, 12... Sliding pin, 13, 14... Chain, 18... Pin rail, 72... Weighing rail,
75...Load cell, 28...Detection section, 29...
Photoelectric switch, 39... Storage device, 40... Fruit data processing device, 41... Number recognition circuit.

Claims (1)

[Scope of Claims] 1. A conveyor means for conveying a plurality of cups on which objects to be sorted are mounted at predetermined intervals, and a conveyor means provided in a conveyance path of the cups to measure the cup load and to adjust the cup load according to the load. A weighing device that outputs an electric signal, a plurality of weight class classification devices installed in series in a conveyance path behind the weighing device, and a receiving box provided on each side of the path of each classification device, a detecting section provided on one of the cups and serving as a cup number reference; a reference detecting means for detecting passage of the detecting section; and a number for recognizing the number of each cup based on the output of the reference detecting means. a recognition means, which compares the electric signal outputted from the weighing device with a reference setting value corresponding to an empty cup load, outputs an empty cup signal when the cup does not carry the object to be sorted; comparing and determining means for outputting a loaded cup signal when the cup is loaded with the object to be sorted; A storage device for updating and writing, and a weight value of the object to be sorted is calculated by subtracting the empty cup signal of the cup stored in the storage device from the placed cup signal, and a class weight corresponding to the weight value is calculated. The classification device is equipped with a data processing device that sends a classification signal at the timing when the measured cups are conveyed to the classification device, and the classification device is operated by the classification signal to separate the objects to be sorted by their weight. Automatic weight sorting device that sorts by weight class.