JPH0516737B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field of the Present Invention> The present invention is a method for grouping a plurality of articles, such as confectionery, fruits, vegetables, etc., whose individual weights vary so that they have a substantially constant weight. This invention relates to a combination weighing device that is used when filling bags into bags.

<Prior Art> (Fig. 4) Even if an attempt is made to group together a plurality of objects to be weighed whose individual weights vary by a set weight, an error will occur between the set weight and the set weight. This error becomes more significant as the average weight of each object to be weighed increases.

To solve this problem, a combination weighing device as shown in FIG. 4 has conventionally been used.

That is, in this combination weighing device, objects to be weighed in an amount corresponding to approximately a fraction of the set weight are placed in the plurality of weighing hoppers 2 ₁ to 2 _o , respectively, to the feeders 1 ₁ to 1 _o.
The weighing devices 3 ₁ to 3 _o provided for each of the weighing hoppers 2 ₁ to 2 _o weigh the objects to be weighed, respectively. And this measuring instrument 3 ₁
Based on the output of ~ _3o , calculate the combination weight for all different combinations. Among these combination weights, for example, the combination with the smallest difference from the set weight and within the range of the upper limit value and lower limit value is selected, and the object to be weighed in the selected weighing hopper is discharged. Then, gather at the group shoot 4 or the like.

However, the set weight value, number of combinations, upper limit value, lower limit value, parameters for controlling the feeding force of each feeder, etc. differ depending on the type of object to be weighed. Each time a change is made, it is necessary to manually change these setting values one by one, which is a cumbersome task.

In order to solve this problem, as described in Japanese Utility Model Application Publication No. 59-27425 and Japanese Patent Application Publication No. 59-46517, each setting value necessary for weighing is stored in advance for each type of object to be weighed. Store it in your memory and when you need it,
These set values were read out all at once from the memory to switch between each set value.

However, even if the feeding power control parameters are constant, the amount supplied by each feeder varies greatly depending on environmental conditions such as temperature and humidity, increasing the probability that an optimal combination will not be obtained. This results in a decrease in efficiency.

For this reason, in conventional combination weighing devices, in order to stabilize the supply amount to the weighing hopper of each feeder, the average supply amount for each feeder is determined, and the feed force control is performed so that this average supply amount always approaches the target weight. Parameters are automatically controlled.

<Problems to be Solved by the Present Invention> However, the conventional device disclosed in JP-A No. 59-46517, which only has the function of recalling one set of parameters from a memory and setting them to each part, cannot automatically control the feeder feeding force. It has been difficult to reuse parameters changed by

In addition, in the case of the combination weighing device of Utility Model Application Publication No. 59-27425, which has a function that allows parameters such as feeder feeding force (vibration time) to be changed by manual key operation,
There was an inconvenience that if the called parameters were changed, the parameters before the change could no longer be used.

An object of the present invention is to provide a combination weighing device that solves the above problems.

<An embodiment of the present invention> (Figs. 1 to 3) Fig. 1 is a schematic diagram of a combination weighing device according to an embodiment of the invention.

In FIG. 1, reference numeral 11 is a feeder that sequentially supplies objects to be weighed to a circular feeder 12. N intermediate hoppers 14 are provided below the periphery of the circular feeder 12.
₁ to 14 _o are arranged in a circle, each with feeder 1
A plurality of objects to be weighed are supplied via 3 ₁ to 13 _o . Weighing hoppers 16 ₁ to 16 _o are installed below the intermediate hoppers 14 ₁ to 14 _o , respectively. The objects to be weighed stored in the intermediate hoppers 14 ₁ to 14 _o are
When the discharge gates 15 ₁ to 15 _o are opened, the samples are dropped into the weighing hoppers 16 ₁ to 16 _o , respectively.

Weighing devices 17 ₁ to 17 _o are installed in the weighing hoppers 16 ₁ to 16 _o , respectively. Measuring instrument 17 ₁ ~
17 _o weighs a plurality of objects to be weighed accommodated in weighing hoppers 16 ₁ to 16 _o , respectively, and outputs the weighed values.

A collection chute 19 is installed below the weighing hoppers 16 ₁ to 16 _o . Weighing hopper 16 ₁ ~
When the discharge gates 18 1 to 18 _o of the weighing hoppers 16 ₁ to 16 _o are opened, the objects to be weighed stored in the weighing hoppers _{16 o} fall into the collection chute 19 .

A packaging machine 21 is installed below the collection chute 19. At the bottom of the collection chute 19, a timing hopper 20 is provided which opens at regular intervals or in synchronization with the packaging machine 21.

The discharge gates 18 ₁ to 18 _o are the combined discharge device 2
The opening/closing is controlled by the discharge control device 27 of No. 4.

The measured values from the scales 17 ₁ to 17 _o are sent to the measured value storage circuit 25 and feeder control circuit 37 of the combined discharge device 24 . The weighing value storage circuit 25 stores the weighing values of the objects contained in the weighing hoppers 16 ₁ to 16 _o , respectively.

The combination setting circuit 26 determines the combined weight of the objects to be weighed based on the weight signals of the objects stored in each of the weighing hoppers 16 ₁ to 16 _o stored in the weighing value storage circuit 25.
Calculate all different combinations, and select the weighing hopper combination that has the smallest difference between the combination weight and the set weight and is within the range of the upper limit value and lower limit value as the optimal combination. , outputs a combination selection signal for the selected combination.

Upon receiving the combination selection signal, the discharge control device 27 opens a designated one of the discharge gates 18 ₁ to 18 _o , and after a certain period of time, opens the discharge gate of the intermediate hopper to the weighing hopper that has already been discharged. Perform opening/closing control to open.

The production control device 28 integrates the total weight of the objects to be weighed selected and discharged by the combination selection circuit 26 and the number of combination discharges, thereby managing the production status of each product type.

That is, the total weight values of the objects to be weighed selected and discharged by the combination selection circuit 26 are sequentially input to the adder 29. The adder 29 adds the value stored in the production weight storage 30 and the total weight value, and stores the addition result in the production weight storage 30 via a switch 31 that is turned ON each time the total weight value is input.

Further, the combination discharge signal from the combination selection circuit 26 is counted by a counter 32.

Memory value of production weight memory 30 and counter 32
The counting results are stored in a setting circuit 52, which will be described later, via switches 33 and 34, respectively, at the end of the weighing operation for one type of product.
5 and 36.

On the other hand, the feeder control circuit 37 determines, based on each input weight value, that the amount of objects to be weighed supplied from each feeder is set to a predetermined target weight (for example, a weight obtained by dividing the set weight by the number of combined hoppers). The feeding force parameters of the feeders 13 ₁ to 13 _o to approach the feeders 13 1 to 13 o are respectively calculated, and the feeding forces of each of the feeders 13 ₁ to 13 _o are respectively controlled based on the calculated parameters.

The feeder control circuit 37 is configured as shown in FIG. 2, for example.

In the figure, the adders 38 ₁ to 38 _o add the measured values input from the scales 17 ₁ to 17 _o and the values stored in the weight accumulation memories 39 ₁ to 39 _o , and the addition results are The weight is newly stored in the weight accumulation storage units 39 ₁ - 39 _o via the switches 40 ₁ - 40 _o . On the other hand, in the adders 41 ₁ to 41 _o , the values stored in the feeding force parameter integration memories 42 ₁ to 42 _o are added to the feeding force parameters at the current stage, and the addition results are sent via the switches 43 ₁ to 43 _o . , are newly stored in the sending force parameter integration storage units 42 ₁ to 42 _o .

Note that the switches 40 ₁ to 40 _o and the switches 43 ₁ to 43 _o are switches that are turned ON in synchronization with the input of the weighing value, and the feeding force parameters are based on the vibration amplitude and vibration time of the vibrator of the feeder. It is a parameter based on

In the dividers 44 ₁ to 44 _o , the weight accumulation memory 39
₁ to 39 _o Sending force parameter integration memory 4
The stored values from 2 ₁ to 42 _o are divided. Multiplier 45 _{1
.about.45.sub.o} , the target weight W/M per hopper set in the setting circuit 52, which will be described later, is multiplied by the division results from the dividers _44.sub.1 to _44.sub.o.

Therefore, the multiplication output of the multipliers 45 ₁ to 45 _o is the ratio of the weight calculation result ΣW and the feeding force parameter calculation result ΣF to the target weight per hopper Wm (W/
The result of multiplying by M), that is, Wm・(ΣF)/(ΣW)...(1), and in the above equation, if K is the number of times of supply, Wm(K/ΣW)(ΣF/K)... It is equivalent to (2). This formula (2) is obtained by multiplying the ratio of the average feed amount up to the number of feeds K and the target weight Wm by the average value of the feeding force parameter, and the calculation result shows that the average feed amount is less than the target value. When it is large, it will be smaller than the average value of the feed force parameter, and when the average supply amount is smaller than the target value, it will be larger than the average value of the feed force parameter, and the next time the feed will always change in the direction of bringing the average feed rate closer to the target value. The force parameters are shown.

The multiplication results from the multipliers 45 ₁ to 45 _o are sent to the sending force parameter memory 4 via switches 46 ₁ to 46 _o that are turned on every predetermined number of times of measurement (for example, every P times).
7 ₁ to 47 _o .

The values stored in the sending power parameter memories 47 ₁ to 47 _o are stored in the adders 41 ₁ to 41 _o and the timer circuits 48 ₁ to 4
8 sent to _o .

The timer circuits 48 ₁ to 48 _o output drive signals having vibration amplitudes and vibration times according to the values stored in the sending force parameter memories 47 ₁ to 47 _o . Timer circuit 4
The drive signals from 8 ₁ to 48 _o are output to each feeder drive circuit 49 ₁ to 49 _o , respectively.

The feeder drive circuits 49 ₁ to 49 _o amplify the drive signals from the timer circuits 48 ₁ to 48 _o and drive the feeders 13 ₁ to 13 _o , respectively.

Note that the values stored in the feeding force parameter memory devices 47 ₁ to 47 _o are initialized from a setting circuit 52 to be described later via switches 50 1 to 50 o at the start of the weighing operation for one type of product, and the values stored in the feeding force parameter storage units 47 1 to 47 o are initialized via switches 50 ₁ to 50 _o from a setting circuit 52 to be described later. At the end of the operation, the final stored values of the sending force parameter memories 47 ₁ - 47 _o are outputted to the setting circuit 52 via the switches 51 ₁ - 51 _o and stored therein. In addition, switch 5
0 ₁ to 50 _o are initial setting means of this measuring device, and switches 51 ₁ to 51 _o are initial value updating means.

The setting circuit 52 includes the combination discharge device 24 described above,
Production control device 28 and feeder control circuit 37
Output the necessary setting values for each product type,
Perform initial settings for weighing operation.

FIG. 3 is a diagram schematically showing the setting circuit 52. As shown in FIG.

In the figure, a numeric keypad 53 is used to input initial values of each set value for weighing a new product and to specify a storage area. The command key 24 is a setting key 5 for inputting and setting each setting value of the new model.
4a, a call key 54b for calling each setting value corresponding to the product type, and a storage key 54c for instructing storage. Control circuit 55
uses the numeric keypad 53 and command key 54 to transfer each setting value stored in the recall parameter memory 56 to the specified area A ₁ of the product type parameter memory 57.
~A _n , and also type-specific parameter memory 5
Among the setting values stored in the designated areas A ₁ to _{A n} of 7, each setting value of the specified product type is called into the calling parameter memory 56.

The recall parameter memory 56 stores various setting values (setting weight a ₁ , upper limit a ₂ , lower limit a ₃ , number of combined hoppers) necessary for the weighing operation of the specified product.
a ₄ , target weight per hopper a ₅ , feeder feeding force parameters b ₁ , b ₂ , ... b _o , total production quantity c ₁ , total production weight c ₂ ) are stored and set, and each of these set values ,
It is output to the combination discharge device 24, the production control device 28, and the feeder control circuit 37.

Further, setting values that change during the weighing operation, such as the feeder power parameters b ₁ to _bo and the total production quantity c ₁ , are stored and updated with the final values when the weighing of the product type is completed. In addition, the call parameter memory 5
The stored value of 6 is displayed by the display circuit 58.

The type-specific parameter memory 57 stores each set value necessary for a weighing operation for each type.

<Operation of the above embodiment> Next, the operation of the combination weighing device according to the above embodiment will be described.

For example, when starting a weighing operation for a new product, press the setting key 54a of the setting circuit 52 to store the set weight a ₁ and upper limit in the recall parameter memory 56.
a ₂ , lower limit a ₃ , number of combined hoppers a ₄ , and target weight per hopper a ₅ are input and set in sequence using the numeric keypad 53. Next, set feeder feeding force parameters b ₁ , b ₂ , ... b _o to values that seem appropriate, and set the total production quantity c ₁ and total production weight c ₂ to zero since it is a new product. .

Here, when the weighing operation is started, each setting value necessary for combination selection is set from the recall parameter memory 56 to the combination selection circuit 26, and the feeding force parameters b ₁ , b ₂ , ... b _o of each feeder are set. is initially set in the feeding force parameter memory 47 ₁ - 47 _o via the switches 50 ₁ - 50 _o of the feeder control circuit 37, and the feeder 13 ₁ -
13 _o is driven.

The object to be weighed is supplied to intermediate hoppers 14 1 to 14 _o by feeders 13 ₁ to 13 _o , respectively, via the feeder ₁₁ and the circular feeder 12.
4 ₁ to 14 _o are accommodated in each weighing hopper 16 ₁ to 16 _o , and weighed by scales 17 ₁ to 17 _o , respectively.

The measured value storage circuit 25 stores the measured values for each weighing hopper from the measuring instruments 17 ₁ to 17 _o .

The combination selection circuit 26 calculates, based on the stored weighing values, the combined weights of the combinations of weighing hoppers with the number of combined hoppers a ₄ for all different combinations, and calculates the combination weight that has the smallest difference from the set weight a ₁ ,
A combination of weighing hoppers within the range of upper limit _a2 and lower limit _a3 is selected, and a combination selection signal is sent to the discharge control device 27.

The discharge control device 27 opens the discharge gate of the weighing hopper designated by the combination selection signal and causes the discharge to the collection chute 19. The objects to be weighed are grouped together in a collection chute 19, and when a timing hopper 20 is opened, they fall into a packaging machine 21 and are packed into bags. Next, the combination is determined in the same manner using the remaining weighing hoppers, and the combination is discharged.

Simultaneously with this combined discharge, the total weight value of the discharged objects to be weighed is sent to the adder 29 of the production control device 28. At this time, the production weight storage device 30
This total weight value is stored in the production weight memory 30 since it has been reset by the zero set in the recall parameter memory 56. Further, the combination ejection signal is input to the counter 32, but at this time, the count of the counter 32 is preset to zero set in the recall memory 56, so the count of the counter 32 becomes "1".

The weighing hopper that has already been discharged receives the object to be weighed via the feeder and the intermediate hopper, and the weighing device outputs the weighing value for the newly accommodated weighing hopper. In this way, while discharging and filling the weighing hoppers continuously, combined discharges are performed one after another, and the production weight memory 30 stores the total production weight of the product type, and the counter 32 stores the total production weight of the product type. The total number of products produced will be accumulated and stored.

In addition, the measured values from each measuring device 17 ₁ to 17 _o are as follows:
Adder 38 ₁ of feeder control circuit 37 for each measurement
38 _o .

_Here , for example, _the weight values _{W 1 ,} W ₂ , . Further, the stored value b ₁ of the sending power parameter memory 47 ₁ initialized by the setting circuit 52 is also sequentially added by the adder 41 ₁ in synchronization with this,
The transmission force parameter is integrated and stored in the integrated storage unit 42 ₁ .

When the P-th weighing value Wp is added, the switch 46 ₁ is turned on, so that the stored value W ₁ +W ₂ +...+Wp of the weight accumulation memory 39 ₁ is obtained in the sending force parameter accumulation memory 42 ₁ The value obtained by dividing the measured value P×b ₁ of , multiplied by the target weight a ₄ per hopper, that is, [(P×b ₁ )/(W ₂ +W ₂ +…+Wp)]×a ₄ is updated and stored in the feeding force parameter storage 47 ₁ as a new feeding force parameter b ₁ ′, and the feeding force of the feeder from the next time onwards is driven by the feeding force corresponding to this feeding force parameter b ₁ ′, The supply amount from the next supply is controlled so that it approaches the target weight MW. Exactly the same control is performed for the other feeders 13 ₂ to 13 _o , and the feeding force parameters of each feeder are automatically updated.

Next, when finishing the weighing of the above types, each switch 51 ₁ to 51 _o of the feeder control circuit 37 is turned on at the end of the weighing operation, and furthermore, the switches 33 and 34 of the production control device 28 are turned on. The final sending force parameters stored in the sending force parameter memories 47 ₁ to 47 _o are stored in the calling parameter memory 56 of the setting circuit 52 . Further, the final stored values of the production weight storage unit 30 and the counter 32 are also stored in the same manner.

Here, by pressing the storage key 54c of the setting circuit 52 and specifying the area A ₁ , A _{2 ,} . Each initial setting value is stored in the type parameter memory 57.

Therefore, when weighing the above types again,
By pressing the call key 54b of the setting device 52 and specifying the area of the type parameter memory 57 stored last time using the numeric keypad 53, each initial setting value necessary for weighing will be output to the call parameter memory 56, and the final setting value from the previous measurement will be output. The weighing operation can be performed immediately from the weighing state.

Note that, as described above, the feeding force parameters stored in the recall parameter memory 56 can be initialized to the feeder control circuit 37 via the switches 50 ₁ to 50 _o that are turned on at the start of the next metering operation. When restarting the weighing operation of a variety of objects to be weighed after a short period of suspension, the parameters may be set directly from the recall parameter memory 56 to the feeder control circuit 37.

In addition, if the metering operation of a product whose feed force parameters have been automatically updated significantly due to long-term continuous operation is completed, and if the operation will not be performed for a long time, the feed force parameters that have been significantly updated may be If the force parameter is not updated and stored in the product type parameter 57, the feed force parameter before being updated can be used as the initial feed force parameter for the next operation of this product type.

<Other embodiments of the present invention> In addition, each setting value necessary for measurement in the above embodiment,
A control parameter that controls the speed of the entire weighing operation may be added as a set value for each product type.

Further, the feeder control circuit 37 is not limited to the above embodiment, and for example, the feeder control circuit 37 calculates the feeding force parameter from the difference between the average value of the measured values A times and the target weight per hopper. Therefore, the supply amount may be trend-controlled.

<Effects of the Present Invention> Since the combination weighing device of the present invention is configured as described above, it is possible to initialize the feeding force parameters of each feeder recalled from the type parameter storage means to the feeder control means. Of course, it is possible to temporarily store the feeding force parameters of each feeder that have been automatically updated by the feeder control means in the recall parameter storage means, and then set this stored value directly to the feeder control means as initial parameters again. The parameters can be freely stored in the type parameter storage means as initial parameters for the next operation, and the best parameters can be set according to the metering operation situation.

[Brief explanation of the drawing]

Fig. 1 is a schematic block diagram of a combination weighing device according to an embodiment of the present invention, Fig. 2 is a schematic block diagram showing a feeder control circuit of an embodiment, and Fig. 3 is a schematic diagram showing a setting circuit of an embodiment. It is a block diagram. Fourth
The figure is a schematic configuration diagram of a conventional combination weighing device. 13 ₁ ~ 13 _o ... feeder, 16 ₁ ~ 16 _o ......
Weighing hopper, 17 ₁ ~ 17 _o ...Measuring device, 24...
Combination discharge device, 28... Production control device, 37...
...Feeder control circuit, 38 ₁ to 38 _o ... Adder,
39 ₁ to 39 _o ...Weight integration memory circuit, 41 ₁ to 4
1 _o ... Adder, 42 ₁ to 42 _o ... Sending force parameter integration memory, 44 ₁ to 44 _o ... Divider, 45 ₁
~45 _o ...Divider, 47 ₁ ~47 _o ... Transmission power parameter memory, 48 ₁ ~48 _o ... Timer circuit, 4
9 ₁ to 49 _o ... feeder drive circuit, 52 ... setting circuit, 53 ... numeric keypad, 54 ... command key, 5
4b... call key, 54... storage key, 55...
Control circuit, 56...Recall parameter memory, 57
...Type-specific parameter memory.

Claims (1)

[Scope of Claims] 1. A plurality of weighing hoppers 16 ₁ to 16 _o , a plurality of weighing instruments 17 ₁ to 17 _o that respectively weigh objects to be weighed supplied to the plurality of weighing hoppers, and the plurality of weighing instruments. a combination discharging device 24 that selects the optimal combination of the objects to be weighed weighed by the respective weighing values based on each weighing value and discharges the selected objects to be weighed; A plurality of feeders 13 _{1 to 13} feed objects to be weighed into empty weighing hoppers among the plurality of weighing hoppers by force, respectively.
13 _o , and based on the weighing signals from the plurality of weighing instruments,
a feeder control circuit 37 that automatically updates the parameters in a direction that brings the next amount of objects to be weighed from each feeder to each weighing hopper closer to a predetermined amount; and a plurality of initial parameters corresponding to the initial feeding force of each feeder. , a type-specific parameter storage means 57 that is stored in advance for each type of object to be weighed, and calling means 54b, 55 that retrieves initial parameters of a desired type from the type-specific parameter storage means.
and a call parameter storage means 56 for storing a plurality of initial parameters of the specified product called up by the call means, and a call parameter storage means 56 that stores the plurality of parameters stored in the call parameter storage means as initial parameters for the plurality of feeders. initial setting means 50 ₁ to 50 _o that initializes the feeder control means as follows; and initial value updating means 51 ₁ that updates and stores a plurality of parameters automatically updated by the feeder control means in the call parameter storage means. ~51 _o
and storage means 54c and 55 for storing the parameters stored in the call parameter storage means in the type parameter storage means.