JP2990465B2 - Combination weighing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for distributing articles supplied to a dispersing device by an article carry-in device to a plurality of weighing sections, and for weighing the articles weighed in each weighing section based on the measured values. The present invention relates to a combination weighing device for performing combination discharge.

[0002]

2. Description of the Related Art In order to combine articles having variations in individual weight by a target amount,
Conventionally, a combination weighing device shown in FIG. 6 has been used.

In this combination weighing apparatus, an article carry-in conveyor 1 carries articles in an article receiver 1a into a top 2a of a dispersion feeder 2, and a circular umbrella-shaped dispersion feeder 2 has a top 2a.
Feeder 3 arranged on the outer periphery of the article received by
₁ vibration dispersed to to 3 _n direction, the radiating feeders 3 ₁ to 3
_n means that each intermediate hopper 4
Articles are supplied to each of ₁ to 4 _n almost every predetermined amount.

[0004] supplied to the intermediate hopper 4 ₁ to 4 _n articles are supplied to the weighing hopper 5 ₁ to 5 _n, is metered by the respective meter 6 ₁ to 6 _n.

[0005] When receiving the combination request signal from a packaging machine (not shown) or the like, the combination selection circuit 10 receiving the measurement value signals from the respective weighing devices 6 _{1 to} 6 _n performs the combination calculation of the measurement values. A combination within a predetermined target weight range is selected, and a selection signal is output to the weighing hopper opening / closing circuit 11.

A weighing hopper opening / closing circuit 11 receiving a selection signal
Simultaneously open and close the weighing hoppers selected for the combination, discharge the articles to the collecting chute 7, and collectively discharge them to the packaging machine or the like.

On the other hand, the intermediate hopper opening / closing circuit 12 causes articles to be supplied from the intermediate hopper corresponding to the empty weighing hopper, and the radiation feeder driving circuit 13 supplies new articles from the radiation feeder corresponding to the empty intermediate hopper. Supply the goods.

The dispersion feeder driving circuit 14 always drives the dispersion feeder 2 to vibrate except when all the radiation feeders are continuously stopped for a predetermined time.

When the amount of articles on the dispersion feeder 2 is reduced to a predetermined amount or less while the combination discharging operation is repeatedly performed, the articles are replenished from the article carry-in conveyor 1.

As shown in FIG. 7, this reduction in the amount of articles
Floodlight 1 for projecting light that traverses over the top of the dispersion feeder 2
5 and a light receiver 16 that receives light from the light emitter 15, and the light reception signal is input to a level determination circuit 17.

The level determination circuit 17 is provided to block light incident on the light receiver 16 by a disturbing object, light shielding by an article being carried in, falling, or light reception by a gap or the like generated between articles at the top of the dispersion feeder 2. to eliminate the influence of light, such as by the disturbance light, it is composed of a retrigger type timer circuit or the like, since the light receiver 16 is changed to the light receiving state from the non-light-receiving state, the receiving state a predetermined time (T _oN) At the time of continuation, an activation signal for activating the article loading by the article loading conveyor 1 is output. Conversely, when the state changes from the light receiving state to the non-light receiving state, the non-light receiving state changes for a predetermined time (T
_OFF ) Stops the output of the start signal when continued.

Accordingly, as shown in FIG. 8A, the article amount (height) on the dispersion feeder 2 is reduced from the time t ₁ at which the light emitting / receiving level R is reduced to the time t ₂ at which the T _ON time is further elapsed, at which time the article is removed. the article carrying-by input conveyor 1 is started, the article weight from time t ₃ when increased to R, at t ₄ has passed more T _OFF time, the article conveyed is stopped, the article of the dispersion feeder 2 is substantially projecting The light reception level R is regulated.

However, since the work of replenishing the goods in the goods receiver 1a of the goods carry-in conveyor 1 often depends on the manual connection with the production line, the discharge amount of the goods carry-in conveyor 1 per unit time is large. fluctuate.

When articles are carried into the dispersion feeder 2 in a state where the amount of discharge per unit time is large, a large quantity of articles is carried during the T _OFF time as shown in FIG. 8B. Will be.

When a large amount of articles is carried in such a short time, a large variation in the quantity of the articles appears as a variation in the quantity of the articles discharged from each radiation feeder. A high-precision combination cannot be obtained with a weighing device for which an article supply is desired.

On the other hand, when the articles are carried into the dispersion feeder 2 in a state where the discharge amount per unit time is small, as shown in FIG. Extremely long. In this state, the shortage state of the articles continues for a long time, so that a highly accurate combination cannot be obtained.

Further, in this shortage state, if the discharge amount from the article carry-in conveyor 1 is further reduced, the carry-in amount cannot be sufficient for the amount of articles consumed by the weighing and discharging operation, and the operation of the weighing device is stopped. There is also a situation that must be done.

An object of the present invention is to provide a combination weighing device which solves this problem.

[0019]

In order to solve the above-mentioned problems, a combination weighing device according to the present invention comprises a plurality of weighing sections for weighing articles received by an article receiver with a weighing device, and weighing the articles by the weighing sections. Among the articles, a combination in which the combination of the weighing values is within a predetermined range is selected, and a combination discharging means for discharging the selected articles from the weighing section, and the articles received at a predetermined receiving location are sent to the plurality of weighing sections. Dispersed into a plurality of corresponding paths, to the weighing unit from which the articles are discharged by the combination discharge means, a distributed supply device that supplies the articles from the corresponding paths,
An article amount detecting means for detecting that the amount of the article on the dispersion supply device has decreased to a predetermined amount or less, and an article in a receiving place of the dispersion supply apparatus while receiving a detection signal from the article amount detection means. And a total discharge detecting means for detecting the total discharge amount of the articles combined and discharged from the weighing unit within a predetermined period, and from the article carry-in device to the dispersion feeder within the predetermined period. The carry-in frequency detecting means for detecting the carry-in frequency or carry-in cumulative time in which the article was carried in as the carry-in frequency, the total discharge amount detected by the total discharge amount detecting means, and the carry-in frequency detected by the carry-in frequency detecting means. The average carry-in amount calculating means for calculating an average carry-in amount per unit carry-in frequency of the article carry-in device during the predetermined period, and the average carry-in amount calculated by the average carry-in amount calculating means are: In a direction approaching to the amount, and a carry-control means for variably controlling the article carrying-force of the article carrying apparatus.

[0020]

Since the combination weighing device of the present invention is configured as described above, when the combination discharge of articles from the weighing section continues for a predetermined period, the total discharge amount is detected, and the article discharge device during this period detects the total discharge amount. An article carry-in time or number is detected, and a carry-in quantity per time or a carry-in quantity per time is calculated. Then, the carry-in input of the article carry-in device is controlled so that the calculated value approaches a predetermined value.

[0021]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a combination weighing device according to one embodiment.

This combination weighing apparatus is similar to the above-mentioned conventional apparatus, in that an article carrying conveyor 1, which is an article carrying apparatus,
Top 2a of the dispersion feeder 2 to form a radiation feeders 3 ₁ to 3 _n and the intermediate hopper 4 ₁ dispersion feeder with to 4 _n
The goods are supplied to. Articles distributed on the dispersion feeder 2, the radiating feeders 3 ₁ to 3 _n and the intermediate hopper 4 ₁
It is supplied to the weighing hoppers 5 ₁ to 5 _n through to 4 _n.

The articles contained in the weighing hopper 5 ₁ to 5 _n is metered at each meter 6 ₁ to 6 _n. The weighing signal of each weighing device is output to the combination selection circuit 10.

[0025] Combination selection circuit 10, as shown in FIG. 2, a memory 10a for storing the weighing signal from each measuring instrument 6 ₁ to 6 _n, are configured and combined adder 10b, the determination unit 10c .

Upon receiving the combination request signal, the combination adder 10b sequentially performs the combination addition of the weighing values stored in the memory 10a in accordance with different combination patterns, and sequentially outputs the added value to the decision unit 10c to make a decision. The combination pattern at the time of receiving the pattern holding signal from the container 10c is held and the combination pattern is output to the weighing hopper opening / closing circuit 11 as a selection signal.

The determiner 10c determines whether or not the addition result of the combination adder 10b falls within a preset target weight range. When the addition result falls within the target weight range, the pattern is sent to the combination adder 10b. Output the hold signal.

The weighing hopper opening / closing circuit 11 (see FIG. 1)
The weighing hopper selected for the combination is opened and closed, and the combined articles are collectively discharged through the collecting chute 7.

The intermediate hopper opening / closing circuit 12 opens and closes the intermediate hopper corresponding to the empty weighing hopper to supply new articles to the weighing hopper, and the radiation feeder driving circuit 13 controls the radiation corresponding to the empty intermediate hopper. The feeder is driven to supply new articles to the intermediate hopper.

The dispersion feeder drive circuit 14, the radiation feeders 3 ₁ to 3 _n is in while being driven with no intervals or the predetermined time T _B, continuously drives the dispersion feeder 2,
All radiation feeders stops and the state is stopped subsequent T _B time driving the dispersion feeder 2.

On the other hand, the light receiver 1 for receiving the light of the light projector 15
The light receiving signal from 6 is input to the level determination circuit 17.

The start signal from the level determination circuit 17 is input to the carry-in frequency detection circuit 20 and the conveyor speed control circuit 25.

The carry-in frequency detection circuit 20 accumulates the time during which the activation signal is output from the level determination circuit 17 until a reset signal described later is received.

On the other hand, every time the total emission detecting circuit 21 receives the pattern holding signal from the decision unit 10c of the combination selection circuit 10, the total output detection circuit 21 integrates the addition output of the combination adder 10b at that time and outputs the integrated value. I do.

The average carry-in amount calculating circuit 22 receives a latch pulse from a latch pulse output circuit 31, which will be described later, and latches the integrated value from the total discharge amount detecting circuit 21 and the integrated value from the carry-in frequency detecting circuit 20. Then, the total discharge amount is divided by the cumulative carry-in time, and the calculation result is output to the conveyor speed control circuit 25 as an average carry-in amount per unit time.

If the calculation result from the average carry-in amount calculation circuit 22 is larger than the preset target amount Wr, the conveyor speed control circuit 25 carries in the article carry-in amount corresponding to the difference from the next carry-in. Decrease the speed of the conveyor 1.

Conversely, the latched calculation result is the target amount Wr
If the number is less, the speed of the article carrying conveyor 1 is increased.

As the target amount Wr, for example, the product of the combination target weight and the number of times the combination request signal is input per unit time (ie, the expected discharge amount W ₀ per unit time)
Is set twice in advance.

Each time the timer circuit 30 receives a reset pulse from the reset pulse generation circuit 32, it outputs a high-level timer pulse to the latch pulse generation circuit 31 for a predetermined time (Th) as shown in FIG. Output.

The latch pulse generation circuit 31 outputs a latch pulse to the average carry-in amount calculation circuit 22 and the reset pulse generation circuit 32 every time the timer pulse falls to a low level, as shown in FIG.

The reset pulse generation circuit 32 receives a latch pulse from the latch pulse generation circuit 31 or a start signal input by operating a switch (not shown), as shown in FIG. Thus, a reset pulse is output at a timing slightly delayed, which can be ignored with respect to Th. The reset pulse restarts the timer circuit 30 and resets the carry-in frequency detection circuit 20 and the total discharge amount detection circuit 21.

Next, the operation of the combination weighing device will be described.

Now, on the dispersion feeder 2, the light emitting and receiving
The operation is started in a state where articles are supplied in a state higher than 5 and 16 and the weighed hoppers 5 _{1 to} 5 _n contain weighed articles. It is assumed that a signal is input.

Therefore, the timer circuit 30 is started almost in synchronization with the start of operation, and the carry-in frequency detection circuit 2
0 and the output value of the total emission amount detection circuit 21 are reset to zero.

Here, when the combination request signal is input from the packaging machine, the combination addition of the weighing values stored in the memory 10a of the combination selection circuit 10 is started by the combination adder 10b according to different combination patterns. When a combination addition value that falls within the set weight range is output, the determination unit 10
From c, the pattern holding signal is output to the combination adder 10b and the total discharge amount detection circuit 21.

For this reason, a combination selection signal is output from the combination adder 10b to the weighing hopper opening / closing circuit 11, and the articles selected for the combination are simultaneously discharged from the weighing hopper.
It is housed in a packaging machine or the like via the collecting chute 7.

Further, the total discharge amount detection circuit 21
0c, the combination adder 1
The output value of 0b is stored as the first discharge amount.

A new article is supplied to the empty weighing hopper from the intermediate hopper opened and closed by the intermediate hopper opening and closing circuit 12. The radiation feeder corresponding to the empty intermediate hopper is driven by the radiation feeder driving circuit 13 for a predetermined time, and a new article is supplied to the intermediate hopper.

The dispersion feeder 2, a state where all of the radiation feeders is stopped, unless it continues for a predetermined time T _B above, to distribute the continuous article to each radiation feeder direction.

Thereafter, similarly, each time a combination request signal is input, a combination is selected, and when a combination within the set weight range is selected, the combination article is discharged. For this reason,
The output value of the total emission amount detection circuit 21 is determined while the combination request signal is continuously input as shown in FIG.
Increases with time after start of operation t ₀ as shown in the figure (b).

On the other hand, if the articles on the dispersion feeder 2 become lower than the light emission / reception level R during such a series of weighing and discharging operations, a start signal is output from the level determination circuit 17.

While the weighing and discharging operation is repeated, as shown in FIG. 4C, when the amount of articles on the dispersion feeder 2 has decreased below the light emitting / receiving level R, the T _ON time has elapsed ( At t ₁ ), a start signal is output from the level determination circuit 17, and the article carry-in conveyor 1 is driven to carry in the article at a predetermined initial speed V ₀ , as shown in FIG.

When the first article carry-in is started and the T _OFF time has elapsed since the quantity of articles on the distributed feeder 2 has reached the light emitting / receiving level R (at t ₂ ), the output of the start signal from the level determination circuit 17 is performed. Stops, and the drive of the article carrying-in conveyor 1 is stopped. The carry-in time T _{d1 at} this time is stored in the carry-in frequency detection circuit 20 as an initial value of integration.

Similarly, every time the amount of articles on the dispersion feeder 2 decreases below the light emitting / receiving level R, the article carry-in conveyor 1 is driven to replenish articles, and their carry-in times are integrated.

Then, the total discharge amount W ₁ and the total carry-in time Td at time t ₃ when the time Th (time until the output of the timer circuit 30 falls) from time t ₀ is latched in the average carry-in amount calculation circuit 22. is, W ₁ / Td, _{i.e., W 1 / (Td 1 +} Td 2 + ... + Td m) is calculated.

The result of this calculation is output to the conveyor speed control circuit 25 as an average carry-in amount per unit time of the article carry-in conveyor 1 from t ₀ to t ₃ .

If the slope from t ₁ to t _{2 in} FIG. 4C is more than twice as large as the slope of the discharge amount in FIG. 4B, (the carry-in amount per unit time is large). In the case, the calculation result of the average carry-in amount calculation circuit 22 is larger than the target amount Wr.

[0058] Therefore, from the next article loading (t _4:00), carrying the articles it is performed at a rate of the initial velocity V ₀ slower V _1.

Due to the variable speed, the fluctuation of the article amount of the dispersion feeder 2 is reduced.

Conversely, when the carry-in amount per unit time from the article carry-in conveyor 1 is smaller than the target amount Wr, the carrying speed of the article carry-in conveyor 1 is changed to a state faster than the previous speed.

As described above, the average carry-in amount of the article carry-in conveyor 1 per unit time is detected every Th time, and the speed of the article carry-in conveyor 1 is variably controlled in a direction in which the value approaches the target amount. Variations in the amount of articles on the dispersion feeder 2 due to the state of article supply to the article carry-in conveyor 1 can be reduced, and operation can be continued while maintaining highly accurate combination weighing.

[0062] Incidentally, the convenience of the packaging machine or the like, the driving state is not input a combination request signal is T _B time lasted t ₆ o'clock dispersion feeder 2 o'clock t ₅ as shown in FIG. 4 (a) is stopped You. The article of the dispersion feeder 2 in this state is not reduced, again the combined request signal is one of the radiation feeders Izure entered at t ₇ being driven, are again dispersion feeder 2 driven.

In this embodiment, a conveyor-type apparatus is used as the article carrying-in apparatus. However, when the conveying force of the vibration-feeder-type article carrying-in apparatus is varied, the vibration intensity may be varied.

When a bucket-type carry-in device is used, the total amount of discharged articles divided by the number of buckets ejected within a predetermined period is closer to the target amount, and the input amount to each bucket is increased. Can be changed.

In the above-described embodiment, the decrease in the number of articles on the dispersion feeder 2 is detected by the light emitter / receiver. However, this is not a limitation of the present invention. For example, the dispersion feeder 2 is placed on a scale. When the weight detection value of the weigher becomes equal to or less than a predetermined value, a new article may be supplied.
In this case, if a natural dispersion type, that is, a dispersion feeder that does not vibrate is used, the weight of the scale can be easily detected.

In the above embodiment, the dispersion feeder 2
Although radiation feeders 3 ₁ to 3 _n and the intermediate hopper 4 ₁ dispersion feeder by to 4 _n has been formed, the form was omitted intermediate hopper or, as shown in FIG. 5, the article receiving portion 4
A plurality of feeders 42, 4 arranged in parallel
The same can be applied to a weighing device having a dispersion feeder that carries out the dispersion in 2, 42,.

In the above-described embodiment, the carrying force of the article carrying-in device is changed every Th time. However, the carrying force or the combined discharging number of the article carrying-in device may be performed every predetermined number of times. Good.

Further, in the above-described embodiment, each weighing section is constituted by the weighing hopper and the weighing device. However, the weighing hopper is provided with a plurality of article storing sections, and the weighing of the articles stored in each of the storing sections is performed. The present invention can be similarly applied to a combination weighing apparatus having a weighing unit of a type calculated from the output of a container or a type in which articles weighed by one weighing hopper are transferred to another hopper.

In the above-described embodiment, the total discharge amount of the combined discharged articles is obtained by integrating the addition results of the combination selection circuit 10. However, the combination weighing apparatus in which the discharge hopper 8 is provided below the collecting chute 7 is provided. In this case, the amount of articles stored in the discharge hopper may be measured and the measured values may be integrated.

[0070]

As described above, the combination weighing device according to the present invention is based on the combined discharge amount of articles within a predetermined period and the frequency (time or number) of articles carried in from the article carrying device during that period. The average carry-in amount per unit frequency of the article carry-in device is detected, and the carry-in amount of the article carry-in device is variably controlled so that the detected value approaches the target carry-in amount.

For this reason, it is possible to suppress a change in the amount of articles on the dispersing feeder in a stable state without causing an article shortage, to stabilize the quantity of articles supplied to each measuring section, and to perform highly accurate weighing. Become.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a block diagram of a main part of one embodiment.

FIG. 3 is a timing chart of a main part of one embodiment.

FIG. 4 is a timing chart showing the operation of one embodiment.

FIG. 5 is a perspective view showing a main part of another embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a conventional device.

FIG. 7 is a schematic diagram for explaining the operation of the conventional device.

FIG. 8 is a diagram showing a change in the amount of articles on a dispersion feeder of a conventional apparatus.

[Explanation of symbols]

1 article carrying conveyor 2 the dispersion feeder 3 ₁ to 3 _n radiating feeders 4 ₁ to 4 _n intermediate hopper 5 ₁ to 5 _n weighing hoppers 6 ₁ to 6 _n meter 7 collecting chute 10 combination selection circuit 10a memory 10b combined adder 10c determines Unit 11 Weighing hopper opening and closing circuit 12 Intermediate hopper opening and closing circuit 13 Radiation feeder drive circuit 14 Distributed feeder drive circuit 15 Emitter 16 Receiver 17 Level judgment circuit 20 Loading frequency detection circuit 21 Total discharge amount detection circuit 22 Average carry-in amount calculation circuit 25 Conveyor speed Control circuit 30 Timer circuit 31 Latch pulse generation circuit 32 Reset pulse generation circuit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-30725 (JP, A) JP-A-60-10125 (JP, A) JP-A-60-179616 (JP, A) 34432 (JP, U) Fully open 1988-200129 (JP, U) Fully open 1983 58-60238 (JP, U) (58) Fields studied (Int. Cl. ⁶ , DB name) G01G 19/387

Claims (1)

(57) [Claims] 1. A plurality of weighing units for weighing articles received by an article receiver with a weighing device, and a combination of weighed values within each of the weighing units, the combination of which is within a predetermined range. A combination discharging means for discharging the selected article from the weighing unit, and dispersing the articles received at a predetermined receiving location to a plurality of paths corresponding to the plurality of weighing units, and discharging the article by the combination discharging means. A dispense feeder that supplies the articles from the corresponding path to the weighing unit; an article quantity detection unit that detects that the quantity of the articles on the dispense feeder has decreased to a predetermined amount or less; and While receiving the detection signal, an article carry-in device that carries in an article to a receiving place of the distributed supply device, and a total discharge detection unit that detects a total discharge amount of the articles combined and discharged from the weighing unit within a predetermined period. Within the predetermined period A carry-frequency detecting means for detecting the article carrying-carrying number article to the distributed supply on is carried from the apparatus or carrying cumulative time as carrying power, and the total emission amount detected by the total discharge amount detection means,
An average carry-in amount calculating unit that calculates an average carry-in amount per unit carry-in frequency of the article carry-in device within the predetermined period based on the carry-in frequency detected by the carry-in frequency detecting unit, and an average carry-in amount calculation unit. A combination control device for variably controlling an article carry-in input of the article carry-in device in a direction in which the obtained average carry-in amount approaches a predetermined amount.