JPH0715399B2 - Weighing method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a weighing method of a weighing device that weighs objects to be weighed and discharges the objects to be weighed in combination based on the weighing result.

<Problems to be Solved with Prior Art> (FIGS. 8 to 9) Conventionally, a combination-type weighing device has been used to efficiently pack articles having a variation in weight into a predetermined amount and package them. There is.

In this type of weighing device, the objects to be weighed are supplied to a plurality of weighing units (including hoppers and scales), and the weighed objects are combined and discharged in a set amount. There is.

In recent years, therefore, there is a demand for packing not only the same type of objects to be weighed but also several different types of objects to be weighed with high accuracy and high speed in one bag.

When performing such combination weighing of different types of products, as shown in FIG. 8, the weighing units 1A, 1B, 1C divided into, for example, three groups for each type, select a predetermined amount of combination for each type. Then, the selected objects to be weighed are collectively discharged through the chute 2, but various methods have heretofore been used as the selection method.

Hereinafter, a conventional weighing method will be described with reference to FIG. 9 showing the selection operation for each product type with respect to the discharge request signal P.REQ from the packaging machine side or the like.

The first conventional method as shown in FIG. 9 (a) is to select the weighing units 1A, 1B and 1C and output the discharge request signal.
Simultaneously carry out at the nth input timing (Pn) of P.REQ, and simultaneously perform the selected three kinds of objects to be weighed An, Bn, Cn (9th
This is a method of discharging at the timing indicated by the Δ mark in the figure).

This weighing method requires only a short time from the input of the discharge request signal P.REQ to the discharge of the selected objects to be weighed, and high-speed operation is possible. Since they are performed independently, the difference between the set amount determined for each product type and the actual amount of the selected product is added for three product types, and the total amount of the mixed product has a large deviation from the desired amount. There's a problem.

As a solution to this, as shown in FIG. 9 (b),
At the nth input timing of the discharge request signal P.REQ, the selection operation of the weighing units 1A and 1B is performed first, and the selection amount of the combination of the weighing unit 1C is corrected based on the selection result and the desired total amount. Then, there is also a second method of discharging the selected three kinds of objects to be weighed An, Bn, Cn after performing the selecting operation of the measuring unit 1C.

However, with such a weighing method, the emission request signal
The time from the input of P.REQ until a mixed product is obtained takes almost twice as long as that in the first method, and there is a problem that the discharge capacity (the number of discharges per hour) is remarkably reduced.

As described above, the conventional weighing method cannot satisfy both the precision and the discharge capacity, and cannot meet the demand from the user side for highly accurate mixed discharge of various kinds of products.

An object of the present invention is to provide a weighing method that solves such a problem.

<Means for Solving the Problems> In order to solve the problems, in the weighing method of the present invention, among the objects to be weighed supplied to the plurality of weighing hoppers, the total of the weighing values is a set value. Using a plurality of combination weighing units for selecting a combination of objects to be weighed that are close to or equal to each other, participate in each combination of each combination weighing unit, and collect the selected objects to be weighed into one chute to combine the respective weighings. In a weighing method in which an amount of the object to be weighed that is close to the total of the set values of the units is obtained, among the plurality of combination weighing units of the plurality of sets, selected from participating in the combination and released from each predetermined combination weighing unit. The object to be weighed is temporarily stopped at a stop point on the upstream side of the chute, and the weight of the object to be weighed temporarily stopped and the predetermined combination weighing unit are installed. The step of correcting the set value of another combination weighing unit different from the predetermined combination weighing unit by the difference from the value, and the object to be weighed which is selected in combination by the other combination weighing unit based on the corrected set value. Is discharged to the chute together with the objects to be weighed stopped at the stopping point.

<Operation> As described above, according to the weighing method of the present invention, the objects that have been selected as a combination in the previous stage and are discharged from the predetermined assembly and weighing unit are temporarily stopped at the stopping point on the upstream side of the chute. The weighing object is combined and selected by another combination weighing unit in the next step based on the set value corrected by the difference between the weight of the staying weighing object and the set value of the predetermined combination weighing unit. It is discharged to the chute together with the weighing object.

<Embodiment of the present invention> (FIGS. 1 to 4) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view showing a combination type weighing device to which the present invention is applied, and FIG. 2 is a plan view of FIG.

In these figures, 1 is a base formed in a square shape, and four legs 2 are provided at four corners of the lower surface 1a.

On the upper surface 1b of the base 1, three combination weighing units 10, 20, and 30 as weighing units are intensively arranged at substantially equal distances with their outer peripheral portions adjacent to each other.

The combination weighing units 10, 20, 30 are formed identically, and the objects to be weighed dropped and supplied from above are received by circular umbrella-shaped circular feeders 11, 21, 31 and the circular feeders 11,
It supplies to 10 radiant feeders 12, 22, 32 arranged radially around 21, 31, respectively, and stores the objects to be weighed in appropriate amounts in intermediate hoppers 13, 23, 33 provided at the upper part of the outer peripheral portion. To do.

Below the intermediate hoppers 13, 23, 33, the weighing hoppers 14, 24, 34 for receiving the objects to be weighed discharged from the intermediate hoppers 13, 23, 33 and detecting the weight values are the same as the weighing units, respectively. It is arranged annularly on the circumference.

The weighing hoppers 14, 24, 34 are internally partitioned to form two storage portions 15, 16, 25, 26 (35 and 36 not shown), and the intermediate hoppers 13, 23, 33 are The objects to be weighed can be selectively supplied to the storage unit, and the objects to be weighed supplied to the storage unit are weighed by a weighing device (not shown) provided for each weighing hopper 14, 24, 34. .

This weighing is performed by subtracting the weighing value before the object to be weighed is stored in any of the storing portions from the weighing value after the storage.

The assembling / assembling weighing units 10, 20, 30 perform a combination calculation of the measured values of the weighed objects, select a combination close to each set amount, and select the selected objects in each weighing hopper. The combined weighing units 10, 20, and 30 are discharged from the storage portion of.

At the bottom of each combination weighing unit 10, 20, 30 is a collecting chute 1 for collectively discharging the objects to be weighed discharged from the weighing hoppers 14, 24, 34 for each combination weighing unit.
7, 27, 37 are provided.

A discharge hopper for temporarily storing and then discharging the objects to be weighed discharged from the collecting chutes 17, 27, 37 at the discharge ports 17a (27a, 37a are not shown) of the collecting chutes 17, 27, 37.
18 (28 and 38 are not shown) are provided.

Below the combination weighing units 10, 20, 30 formed in this way, a gutter shape for receiving the objects to be weighed from the respective discharge hoppers 18 (28, 38) and guiding them below the center of the base 1. The discharge chutes 40, 41, 42 formed in the above are provided.

Intermediate shutters 40a, 41a, 42a are provided in the middle of the respective discharge chutes 40, 41, 42 to temporarily hold the objects to be weighed discharged from the respective discharge hoppers 18 (28, 38) as shown in FIG. ing. The intermediate shutter is for simultaneously discharging the objects to be weighed discharged from each combination weighing unit with a time lag due to the difference in the fall distance to the integrated chute 45 described later and appropriately mixing them.

The discharge chutes 40, 41, 42 are provided so as to be inclined so that their discharge sides are in contact with the inner peripheral wall of the general chute 45 arranged below the center of the base 1, and the objects to be weighed from the discharge chutes are This comprehensive shoot 45 will be put together.

By providing this discharge chute, the size of the opening of the general chute 45 can be made very small, and maintenance and the like will be very easy.

Below the outlet 45a of the integrated chute 45, the integrated chute 4
Receive the object to be weighed from 5 and move the object to the left and right (first
In the figure), a sorting hopper 46 for alternately sorting and discharging is arranged. The distribution hopper 46 is provided to make up for the fact that the carrying capacity of the packaging conveyor 60, which will be described later, is lower than the discharging capacity of the combination weighing unit.

As shown in FIG. 1, the spacing between the sorting hoppers 47 and 48 is set to be equal to the spacing between the packaging trays 61 conveyed on the packaging conveyor 60 arranged so as to pass through the lower portion of the weighing device. The objects to be weighed discharged from the input hoppers 47 and 48 are supplied to the adjacent packaging trays 61, respectively.

The packaging conveyor 60 intermittently transports the packaging tray 61 at a transportation pitch that is twice the distance between the packaging trays 61.

In the figure, 51, 52, 53 are each combination weighing units 10, 20,
A supply conveyor for supplying the objects to be weighed to 30 from above, 18a (28a, 38a not shown), 40b, 41b, 42 in the figure.
b, 46a, 46b and 47a, 48a are respectively discharge hoppers 18
(28, 38), discharge chute 40, 41, 42, sorting hopper 4
6, and drive devices for driving the opening and closing of the input hoppers 47 and 48, which have a well-known structure and will not be described in detail.

In addition, reference numeral 55 in the figure is hung on the lower surface 1a of the base 1 via a pillar 55a, and is a general chute 45, a sorting hopper 46, and a charging hopper.
It is a support plate for supporting 47 and 48.

The control of the weighing device formed as described above is performed by each control unit 7 in each combination weighing unit 10, 20, 30 as shown in FIG.
0, 80, 90 and the discharge controller 100.

In FIG. 4, the control units 70, 80, 90 are configured in substantially the same manner, and 71, 81, 91 are stored in the respective storage units based on the measurement value signal from the measuring instrument (not shown). The weight value calculator 72, 82, 92 for calculating the weight value of the object to be weighed is a weight value storage unit for storing the weight value for each storage part calculated by the weight value calculator 71, 81, 91. is there.

73, 83, 93 receive the discharge request signal P.REQ, perform a combination calculation of the stored values stored in the weighing value storage units 72, 82, 92, and set the respective setting units 74, 84, 94. This is a combination selection unit that selects a combination close to the set amount.

The combination selection units 73 and 83 of the control units 70 and 80 respectively control the deviation amount between the set amount set in the selection units 74 and 84 and the total measurement value of the objects to be weighed which are actually combined and selected. It is sent to the section 90.

The control unit 90 adds the both deviation amounts and the set amount set in the setting unit 94 in advance by the adder 95, and sets the addition output as a new set amount in the setting unit 94 via the switch 96. .

77, 87 and 97 are the product name and setting section of the object to be weighed.
This is a display unit that displays the set amount that is the combination target for each combination weighing unit initially set to 74, 84, 94, the deviation amount for each combination selection with respect to this set amount, and the accumulated amount, etc. By confirming the display on the display section, the operation state (correction state of the set amount, etc.) of each combination weighing unit can be easily monitored.

78, 88 and 98 open and close the weighing hoppers that store the objects to be weighed selected by the combination selection units 73, 83 and 93 to collect the objects to be weighed in the selected storage units into the chute 17, 27. , 37 for discharging to the discharge hoppers 18, 28, 38, and opening and closing the discharge hoppers 18, 28, 38 at a predetermined timing.

Further, the discharge supply control units 78, 88, 98 drive the radiant feeder to supply a new object to be weighed to the empty intermediate hopper.

Of the discharge supply control units 78, 88, 98, the discharge supply control unit 98 of the combination weighing unit 30 fixes the discharge hopper (38) in the open state at all times, and discharges the objects selected for combination. When this is done, the discharge signal T is output to the other discharge supply control units 78 and 88.

On the other hand, the discharge supply control units 78 and 88 are formed so as to open the respective discharge hoppers 18 (28) in response to the discharge signal T, and until the discharge hoppers 18 (28) become empty, Control so that the selected weighing object is not discharged to the discharge hopper.

Therefore, among the objects to be weighed that have been combined and selected by each of the combination weighing units 10, 20, and 30 almost at the same time, the objects to be weighed selected by the combination weighing unit 30 are the combination weighing unit 10, when the combination is selected in the previous stage. The discharge hopper 18 (2
The discharge hopper is discharged to the discharge chute 40, 41, 42 side together with the object to be weighed discharged to 8), but the object to be weighed selected by the combination weighing unit 10, 20 is empty.
It will be stored in 18 (28).

The combination selection operation of the combination weighing units 10, 20, 30 is activated by the discharge request signal P.REQ from the discharge control unit 100.

The discharge control unit 100 includes the drive devices 40b, 41b, 42b, 46a, 46b.
And 47a and 48a are controlled to control the objects to be weighed on the wrapping conveyor 60.
The intermediate shutter opening / closing unit 101 for opening / closing the intermediate shutters 40a, 41a, 42a at the same time, and the distribution hopper opening / closing unit for alternately driving the driving devices 46a, 46b of the distribution hopper 46. 102 and input hopper 4
The feeding hopper opening / closing unit 103 is configured to alternately drive 7 and 48 driving devices 47a and 48a.

The respective opening / closing sections 101, 102, 103 of the discharge control section 100 are formed so as to operate in a predetermined order.

That is, the loading hopper opening / closing unit 103 alternately opens and closes the loading hoppers 47 and 48 each time receiving a loading request signal from the packaging conveyor 60 or the like to load the objects to be weighed into the packaging tray 61, and the sorting hopper opening / closing unit 102. When any one of the input hoppers 47 and 48 becomes empty, the corresponding driving device side of the sorting hopper 46 is operated to supply the object to be weighed.

When the sorting hopper 46 becomes empty, the intermediate shutter opening / closing unit 101 simultaneously opens and closes the intermediate shutters 40a, 41a, 42a to supply the stagnation object to be weighed to the sorting hopper 46, and each combination selecting unit 73. , 83, and 93, the discharge request signal P.REQ is sent to start the next combination selection operation.

The result of addition by the adder 95 is the discharge request signal P.REQ.
It is set in the setting unit 94 via the switch 96 which is turned on by.

<Operation of the Embodiment> (FIG. 5) Next, the operation of the embodiment will be described.

Prior to the description of the operation, different weighing objects A, B, and C are combined and weighed from the transport conveyors 51 and 5253, respectively.
It is assumed that each of the control units 70 is supplied to 10, 20, and 30, and each of the control units 70 is configured to appropriately mix the objects A, B, and C to be measured in predetermined amounts and discharge a desired total amount of the mixed product. , 80,
It is assumed that a predetermined set amount is set in the setting units 74, 84 and 94 of 90.

The loading hoppers 47, 48 and the sorting hopper 46 have the objects to be weighed A, B selected by the combination weighing units 10, 20, 30, respectively.
A mixed product of C is supplied, and intermediate shutters 40a, 41a,
The objects to be weighed A, B, C selected and discharged from the combination weighing units 10, 20, 30 are stagnant at 42a, respectively, and further, the discharge chute 18 (28) of the combination weighing units 10, 20 is held.
It is assumed that the objects to be weighed A and B that have already been selected are already stored in.

First, when a loading request signal is input from the packaging conveyor 60 to the loading hopper opening / closing unit 103, for example, the loading hopper 48 side is opened and closed, and the mixed product stored in the loading hopper 48 is loaded into the packaging tray 61.

When the feeding hopper 48 is empty, the sorting hopper opening / closing unit 102 stores the mixed product from the sorting hopper 46 in the feeding hopper 48.

When the sorting hopper 46 becomes empty, the intermediate shutter opening / closing unit 101 simultaneously opens / closes the intermediate shutters 40a, 41a, 42a, and the objects to be weighed A, B, C that are stagnant are integrated into the chute 45.
The mixed product is stored in the sorting hopper 46 via the and is mixed appropriately.

Further, since the discharge request signal P.REQ is input to the combination selection units 73, 83, 93 and the switch 96 of the combination weighing units 10, 20, 30 together with this opening / closing, the combination selection of the measurement units 10, 20 is already performed. A deviation amount between the combined measurement value of the objects A and B to be weighed and stored in the discharge chute 18 (28) selected by the weighing units 10 and 20 and set in the setting unit 94. The combination selection in the combination weighing unit 30 is started with the addition result of the amount as a new set amount.

The deviation amount, the initial set amount (target amount) integrated deviation amount, and the like are displayed on the respective display units 77, 87, 97.

When the combination selection is completed in the combination weighing unit 30, the selected object to be weighed C is discharged from the weighing hopper by the discharge supply control unit 98.

The discharged to-be-measured object C stagnates in the intermediate shutter 42a portion of the discharge chute 42 via the discharge hopper (38) which is opened in advance.

Also, along with this discharge, other combination weighing units 10, 20
Since the discharge signal T is sent to the discharge hopper,
The objects A and B stored in 18 (28) are also discharged,
The discharge chutes 40 and 41 are stagnated in the intermediate shutters 40a and 41a, respectively.

When the objects to be weighed are discharged from the discharge hopper 18 (28), the combination weighing units 10 and 20 collectively discharge the objects to be weighed selected at this time to the discharge hopper 18 (28) and The deviation amount according to the weighing result is sent to the combination weighing unit 30.

In the empty storage of each combination weighing unit 10, 20, 30 a new object to be weighed is stored and weighed by the discharge supply control units 78, 88, 98 from the intermediate hopper, respectively The hopper is supplied with the objects to be weighed from the radiation feeders 12, 22, and 32, respectively.

On the other hand, when the next input request signal is input to the input hopper opening / closing unit 103, the input hopper 47 side is opened and closed, and the mixed product is input to the adjacent packaging tray 61.

The packaging conveyor 60 thus has two packaging trays.
When the mixed product is loaded into 61, it is transported by one transport pitch (twice the spacing of the packaging tray 61) to prepare for the next loading.

When the input hopper 47 becomes empty, the mixed product is supplied from the sorting hopper 46 in the same manner as described above, and the intermediate shutters 40a, 41a, 42.
a is opened and closed, and a new mixed product is stored in the sorting hopper 46.

Further, since the discharge request signal P.REQ is output from the intermediate shutter opening / closing unit 101 to the combination weighing units 10, 20, 30 as described above, the combination selection operation is restarted, and the same measurement operation is repeated thereafter. However, each combination weighing unit 10, 20, 3 for the discharge request signal P.REQ during this operation
A timing chart showing the relationship between the combination selection operation of 0 and the ejection operation is as shown in FIG.

That is, objects to be weighed which n-th ejection request signal committee P _n is chosen discharged been input, the objects to be weighed to discharge request signal P _n-1 before the are selected are entered in the combination weighing units 10, 20 Object A
It becomes a mixed product of _n-1 , B _n-1 and the object to be weighed C _n selected by the combination weighing unit 30 when the discharge request signal P _n is input.

Further, as is apparent from FIG. 5, the time until the discharge request signal is input and the three types of objects to be weighed that can be combined are discharged is almost the same as the selected discharge time by one weighing unit. In addition, since the number of weighing units per one weighing unit is large, it is possible to discharge the mixed product with high accuracy and high speed.

In this embodiment, the deviation amounts of the combination selection in the combination weighing units 10 and 20 are simultaneously sent to the combination weighing unit 30 and added to correct the set amount.
The deviation amount of the combination weighing unit 10 is set to the combination weighing unit 20.
To the combination weighing unit 20, and the addition result may be sent to the combination weighing unit 30. By doing so, there is an advantage that each combination weighing unit can be made common.

Although FIG. 5 shows only the selected discharge operation of each combination weighing unit in response to the discharge request signal, the discharge chute
The operation speed of the discharge path from 40, 41, 42 to the input hoppers 47, 48 can be very high speed (only operates in a predetermined order), which limits the discharge capacity of this weighing device. is not.

<Other Embodiments of the Present Invention> (FIGS. 6 to 7) In the above embodiment, three kinds of measuring units were used to carry out mixed weighing of different kinds, but the weighing unit of the present invention is
It is not necessary to have an independent housing as in the above-mentioned embodiment, and it may be provided in the same housing as long as it has a function of weighing and weighing objects to be discharged. .

Further, in the above embodiment, the objects to be discharged at the next discharge request timing are stored in the discharge hopper in a state of being collected by the collecting chute and are stopped, but a part of the weighing is performed. Holding hoppers for staying may be provided below the weighing hoppers of the units, and the holding hoppers may discharge directly to the integrated chute (having a larger diameter than the integrated chute of the above embodiment).

Further, in the above-mentioned embodiment, the set amount of the combination selection in the third weighing unit is corrected based on the deviation amount of the combination selection in the two weighing units. As shown, one weighing unit 110 has two stages of holding means 111, 112 and one weighing unit 120 has one.
Provided stage of holding means 121 (similar means and discharge hoppers in said embodiment) holding the objects to be weighed A _n of the holding means 112 means 1
The objects to be weighed B _{n + 1 of} 21 may be discharged via the chute 150 together with the objects to be weighed C _{n + 2} selected and discharged by the weighing unit 130.

In this case, the set amount for the combination selection of the weighing unit 120 is corrected according to the combination selection result of the weighing unit 110, and the set amount for the combination selection of the weighing unit 130 is further calculated based on the combination selection result of the weighing unit 120. Can be corrected (sequential correction).

Further, in the above-described embodiment, the combination selecting operation of the three weighing units is performed almost at the same time, but this is the case where the interval of the discharge request timing can be minimized, and as shown in FIG. The combination selection operation of the combination weighing units 10 and 20 may be delayed with respect to the request signal P.REQ from the combination weighing unit 30. As a result, the objects to be weighed that have been combined and selected by the combination weighing units 10 and 20 are selected. Can be discharged to the discharge hopper without delay, and the operation of the combination weighing units 10 and 20 can be simplified.

<Effects of the Present Invention> As described above, in the weighing method of the present invention, the combination is selected and discharged from the predetermined combination weighing unit in the previous stage, and temporarily stopped at the stopping point on the upstream side of the chute. The object to be weighed is combined and selected in the next stage by another combination weighing unit based on the set value corrected by the difference between the weight of the stopped object to be weighed and the set value of the predetermined combination weighing unit. Since it is discharged to the chute together with the objects to be weighed, even when mixing and discharging objects of different types to be weighed, etc.
Highly accurate and high speed weighing is possible.

[Brief description of drawings]

FIG. 1 is a front view showing the appearance of an embodiment of a weighing device to which the present invention is applied, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is an enlarged view of a part of FIG. FIG. 4 is a block diagram showing a control unit of one embodiment, FIG. 5 is a timing chart diagram showing an operation of a main part of one embodiment, and FIG. 6 is a schematic explanatory diagram showing another embodiment of the present invention. , FIG. 7 is a timing chart showing the operation of another embodiment of the present invention. FIG. 8 is a schematic explanatory view showing an example of a conventional device, and FIGS. 9 (a) and 9 (b) are timing charts showing an operation example of the conventional device. 10, 20, 30 ... Combination weighing unit, 70, 80, 90 ... Control unit, 100 ... Discharge control unit, P.REQ ... Discharge request signal.

Claims (1)

[Claims] 1. A plurality of combination weighing units for selecting a combination of the objects to be weighed, the total of the weighing values being close to or equal to a set value among a plurality of weighing objects supplied to a plurality of weighing hoppers. In the weighing method, the objects to be weighed selected by participating in the respective combinations of the combination weighing units are collected in one chute to obtain the objects to be weighed in an amount close to the sum of the set values of the respective combination weighing units. Among the plurality of sets of combination weighing units, the objects to be weighed which are selected by participating in the combination and discharged from a predetermined combination weighing unit are temporarily stopped at a stopping point on the upstream side of the chute, and Other combination weighing units that differ from the predetermined combination weighing unit only by the difference between the weight of the object to be weighed and the set value of the predetermined combination weighing unit. The set value of the set value, and the other combination weighing unit discharges the objects to be weighed, which are combined and selected based on the corrected set values, to the chute together with the objects to be weighed retained at the stop location. And a step of performing.