JP3426312B2 - Combination weighing method and 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 combination weighing device for combining and weighing objects to be weighed using a plurality of weighing hoppers having a plurality of storage chambers, and more particularly to a zero point correction thereof.

[0002]

2. Description of the Related Art Generally, when packing objects such as confectionery and pickles that have different weights by target weight, the objects stored in a plurality of weighing hoppers are combined and weighed. A combination weighing device is used. Among the weighing devices of this type, there is a combination weighing device that obtains a large number of combinations by providing a plurality of storage chambers in each weighing hopper.

In this conventional combination weighing device, the objects to be weighed are selectively supplied from a pool hopper to a plurality of storage chambers provided in each weighing hopper and weighed. After the zero point correction, a combination calculation is performed to select a combination of storage chambers within an allowable range based on the target value, and the storage chambers are opened by the opening / closing means to discharge the objects to be weighed.

Here, the zero-point correction value is initially set by the weighing value obtained by weighing the empty weighing hopper weight at the start of the combination weighing. However, during the weighing operation, the zero point shifts due to the drift of the weighing machine due to temperature change or aging and the residue of the object to be weighed attached to the weighing hopper, which causes a weighing error.Therefore, reset the zero point correction value at any time. It is necessary to do it.

In this case, conventionally, the weight detection signal when all the storage chambers of the target weighing hopper are emptied,
It is reset as the zero correction value. For example, a device that resets the zero correction value after waiting for multiple storage chambers of the weighing hopper to be selected and emptied at the same time (see Japanese Examined Patent Publication No. 5-77247), or the target weighing hopper once A device has been proposed in which the weighing hopper is preferentially or forcibly participated in the combination weighing in order to empty it, and the zero point is corrected after discharging (Japanese Patent Publication No. 5-77248 and Japanese Patent Publication No. 5-77249). (See the official gazette).

[0006]

However, these devices have the following problems. As described above, since it is unlikely that all the storage chambers of the target weighing hopper will be emptied at the same time, the zero adjustment will be delayed and the resetting efficiency will be poor. On the other hand, if the weighing hoppers are preferentially or forcibly joined in the combination weighing to empty all the storage chambers of the target weighing hoppers, the combination pattern will be limited, and the weight will fall within the allowable weight range. However, there is a problem in that the frequency of occurrence of so-called errors increases and the efficiency of weighing work decreases, and the number of combinations near the upper limit within the allowable range increases, resulting in a poor production yield.

An object of the present invention is to solve the above problems and to provide a combination weighing device capable of efficiently performing zero correction and realizing highly accurate and high-speed weighing of an object to be weighed.

[0008]

[0009]

[0010]

[Means for Solving the Problems] To achieve the above object
In the combination weighing method according to claim 1 of the present invention,
Weighed from one storage room of the target specific weighing hopper
When an item is discharged from the pool hopper to its storage room
After prohibiting the supply of the objects to be weighed,
Import the measured weight of the object as the first measured value, and
Place the object to be weighed in another storage room of the above specific weighing hopper.
One of the above storages from the pool hopper when stored
Supply the objects to be weighed into the chamber and store it in each storage chamber at that time.
The total measured weight of the objects to be weighed is taken as the second weighing value.
In addition, the objects to be weighed are stored in the above one storage chamber.
The other storage room above depending on the combination selected.
To discharge the objects to be weighed, and then from the pool hopper to the above
Prohibit the supply of the objects to be weighed to the storage room of the
Import the measured weight of the object to be weighed in the delivery room as the third weight value
If there is another storage room, the above storage room
As the above-mentioned one storage room, the above-mentioned taking-in operation is repeated.
Then, the measured values after the 4th are taken in and
To a predetermined performance based on the third and fourth measured values
When the combination of the first step of performing a calculation and setting a new zero correction value and the combination within the above allowable range are not selected, all the storage chambers of the specific weighing hopper are opened to discharge the objects to be weighed. And a second step of setting a new zero-point correction value based on the empty weight of the weighing hopper, and when the combination within the allowable range is not selected during execution of the first step, the second step Execute with priority.

A combination weighing device according to a second aspect of the present invention is a zero point setting pair.
An object to be weighed from one storage room of a particular weighing hopper
Is discharged from the pool hopper to its storage room.
Prohibiting the supply of weighing items and measuring the remaining storage rooms
Import the measured weight of the quantity as the first measurement value, and then
The object to be weighed is stored in the other storage chamber of the above specific weighing hopper.
In the above condition, from the pool hopper to the above one storage room
The objects to be weighed are supplied and stored in each storage chamber at that time.
Import the total measured weight of the measured objects as the second weight value.
In addition, the object to be weighed is stored in the one storage chamber
, The other storage chamber is covered by the combination selection.
Weigh out the sample, and then collect the other items from the pool hopper.
Ban the supply of objects to be weighed into the storage room, and then store the rest
Import the measured weight of the object to be measured as the third measured value,
If there is another storage room, move the above storage room up.
As one storage room, repeat the above loading operation
A signal sequential acquisition means for acquiring the fourth and subsequent measured values, and
Based on the first to third and fourth and subsequent measured values
First zero point that performs constant calculation and sets a new zero point correction value
Setting means, and further, when a combination within the allowable range is not selected, an error discharge opening command signal for opening all storage chambers of a specific weighing hopper to discharge the object to be weighed is opened / closed by the opening / closing means. Secondly, a new zero point correction value is set based on the error discharge command means that is output to the device and the empty weight of the specific weighing hopper from which the object is discharged.
When the combination of the zero point setting means and the allowable range is not selected, the error discharge command means and the second zero point setting means are given priority over the setting of the new zero point correction value by the first zero point setting means. And operation control means.

A combination weighing method according to a third aspect is the combination weighing method according to the first aspect , further, all storage chambers of a specific weighing hopper are opened at a predetermined zero point setting request timing to discharge the objects to be weighed. In the state where the third step of setting a new zero point correction value based on the weight of the weighing hopper is provided and the first step and the second step are not executed,
When the predetermined zero-point setting request timing for the specific weighing hopper is reached, the third step is executed with priority over the second step.

A combination weighing device according to claim 4 claims
In the combination weighing device according to the item 2 , further, forced discharge command means for discharging all objects to be weighed by opening all the storage chambers of a specific weighing hopper at a predetermined zero point setting request timing.
A third zero point setting means for setting a new zero point correction value on the basis of the weight of the specific weighing hopper from which the object to be weighed is discharged, and the priority operation control means uses the first and second zero point setting means. When the predetermined zero point setting request timing for the specific weighing hopper is reached without setting the zero point correction value, the forced discharge command means and the third zero point setting means are preferentially operated.

[0014]

[0015]

According to the invention of claim 1 or 2, the zero point setting pair
In multiple storage rooms of a specific weighing hopper, which is an elephant,
When the objects to be weighed are alternately supplied and discharged, the objects to be weighed
The weight detection signal of the weighing hopper is sequentially supplied every time it is supplied and discharged.
Is taken in as a measured value, and specified based on these measured values.
When a combination within the allowable range based on the target value is not selected in the first step of resetting the zero point correction value by performing the calculation of , the new zero point correction value of the new step Priority is given to the 2nd process over the setting, and "error discharge" is performed for all storage chambers of the specific weighing hopper for which the zero point is set.
Then, a new zero point correction value is set based on the weight of the weighing hopper. Therefore, "alternate discharge" in the first step
Even if the zero point setting is not performed at an appropriate timing by "error discharge", the zero point is reliably reset.

Further, according to the invention of claim 3 or 4, the "alternate discharge" of the invention of claim 1 or 2 or
When the specified zero point setting request timing for a specific weighing hopper is reached without setting a new zero point correction value due to "error discharge" , all storage chambers of the specific weighing hopper for which zero point is set are "forced discharged". Then, a new zero correction value is set based on the weight of the weighing hopper. Therefore, the zero point resetting is surely performed by the "forced discharge" at the predetermined zero point setting timing.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of a mechanical portion of a combination weighing device according to an embodiment of the present invention. The objects to be weighed sent from a supply conveyor (not shown) are collected in the center of the dispersion feeder 4 via the supply chute 2. Then, the vibration of the dispersion feeder 4 causes the radiation feeder 6 (6 _{1 to} 6 _N ) to be distributed and supplied. Then, the objects to be weighed is by vibration of the radiation feeder 6, after being temporarily pooled in accordance with the measurement operation is sent to the pool hoppers 8 (8 ₁ ~8 _N), the discharge gate 16 (16 ₁ to 16 _N ) and 18 (181 to ₁ )
8 _N ) is opened, and the weighing hopper 10 (10 ₁ to 1)
0 _N ), a plurality of storage chambers 20 (two in this example)
It is turned on (20 ₁ ~20 _N) and 22 (22 ₁ ~22 _N). The weight detector 12 (12 _{1 to} 12 _N ) measures the weight of the object to be weighed put into each of the storage chambers 20 and 22 and outputs an analog weight detection signal. The objects to be weighed which weight was measured, the discharge gate 24 (24 ₁ ~24 _N) and 26 (26 ₁ ~26 _N) is opened, is set in the collecting chute 14, it is discharged to the discharge chute 48.

FIG. 2 shows a block diagram of the control unit of this combination weighing device. An analog weight detection signal of each of the storage chambers 20 and 22 of the weighing hopper 10 output from the weight detector 12 is amplified by an amplifier 50, converted into a digital weight detection signal by an A / D converter 52, and a signal sequential acquisition means. 34 and combination calculation means (CPU) 36.

The combination calculation means 36 corrects the zero point of the weighing hopper 10 and selects a combination of the storage chambers 20 and 22 within an allowable range based on the target value to drive the opening command signal S1 to the second gate. It outputs to the means 60, the discharge gates 24 and 26 of the selected storage chamber are opened, and the objects to be weighed are discharged to the discharge chute 48 via the collecting chute 14. The second gate driving means 60 and the discharge gates 24 and 26 constitute the opening / closing means of the weighing hopper 10.

Here, the zero-point correction value WE0 initially set by the initial zero-point setting means 54 for the weighing hopper 10.
Is an amplifier 50 due to a temperature change or a time change during the weighing operation.
Due to the drift of the
Depending on the amount of pickles, etc., the amount of the objects to be weighed attached to the weighing hopper 10 may change, so it is necessary to reset at a predetermined timing.

For this reason, in the present apparatus, the first zero point setting means 38 takes into account the variation of the zero point error so as not to limit the combination pattern, and to make a new setting without emptying all the weighing hoppers for which the zero points are set. A zero point correction value is set to prevent a measurement error. Hereinafter, the operation of setting the zero point correction value will be described with reference to the schematic diagram of FIG. 3 by taking the weighing hopper 10 ₁ as an example.

Now, WE is a zero point error (zero point deviation),
Wa is the weight of the object to be weighed Ma initially loaded into the storage chamber 20 ₁ , Wb is the weight of the object to be weighed Mb initially loaded into the storage chamber 22 ₁ , and Wh is the weight of the object to be weighed Ma in the storage chamber 20 _1. It is the weight of the object Mh to be weighed after being discharged. The zero point setting request generation means 56 measures the predetermined timing, for example, the time, the number of times of participation in the combination for each weighing hopper, and specifies the weighing hopper to be the zero point setting target when the predetermined number is reached. In this state, in FIG. 3A, the weight W0 of the specific weighing hopper 10 ₁ accommodating the objects Ma and Mb to be weighed is measured by the weighing unit 12 ₁ . The zero point error at this time has already deviated from the initial value WE0 set by the initial zero point setting means 54, and if this is WE1 (121 in the figure), the weight W0 is expressed as W0 = Wa + Wb + WE1.

Next, referring to FIG. 3B, the storage chamber 20 ₁
It is assumed that the object Ma to be measured is used for combined weighing and discharged. At this time, the zero point setting request generation means 56
The pool hopper 8 is prohibited by prohibiting the driving of the gate driving means 58.
₁ of the discharge gate 16 _1, 18 ₁ are closed, the weighing hoppers 1
The supply for 0 ₁ is stopped. In this state, the weight W1 which is the first measured value of the weighing hopper 10 ₁ is represented by the following equation. W1 = Wb + WE1 (1)

Next, referring to FIG. 3C, the storage chamber 20 ₁
The object Mh to be weighed is put into the container and the weight W2 which is the second measured value of the weighing hopper 10 ₁ is measured. W2 = Wb + WE1 + Wh (2) From these equations (1) and (2), WH that does not include WE1 can be obtained as in the following equation. Wh = W2-W1 (3)

Next, referring to FIG. 3D, the object to be weighed Mh is measured.
When the object to be weighed Mb is selected and discharged while the object is continuously stored in the storage chamber 20 ₁ , the weight W3 as the third measured value of the weighing hopper 10 ₁ is measured. W3 = Wh + WE1 (4) Substituting equation (3) into equation (4), the zero point error WE1 becomes
It is calculated by the following formula. WE1 = W3−Wh = W3− (W2−W1) The zero point error WE1 thus obtained is set as a new zero point correction value by the first zero point setting means 38. In addition, in FIG. 3D, when the object Mb is not selected but the object Mh is selected, the process returns to FIG. 3B and the states of FIGS. Wait for to occur.

In this way, the present apparatus calculates the zero-point correction value by "alternately discharging" the objects to be weighed in each storage chamber without emptying the two storage chambers of the weighing hopper for which the zero point is to be set at the same time. And set the zero point (zero point setting by alternate discharge).

Next, FIG. 4 shows a case where the storage chamber of the weighing hopper 10 is of a three-chamber type. In this case, the third storage chamber is treated as the first storage chamber and the signal acquisition operation shown in FIG. 3 is repeated to set the zero point. That is, WE is a zero point error, Wa is the weight of the object to be weighed Ma initially loaded into the storage chamber 72 ₁ , and Wb is the object to be weighed M in the storage chamber 74 _1.
Let bc be the weight of the object Mc to be weighed in the storage chamber 76 ₁ and Wk be the weight of the object Mk to be weighed after the object Ma has been discharged into the storage chamber 72 ₁ . Also, Wm
Is the weight of the object Mm to be weighed after the object Mb has been discharged into the storage chamber 74 ₁ .

In FIG. 4A, the objects to be weighed Ma, Mb, M
The weight W0 of the weighing hopper 10 ₁ accommodating c is measured including the zero point error WE1 (123 in the figure) at this time. W0 = Wa + Wb + Wc + WE1

Next, referring to FIG. 4B, the storage chamber 72 ₁
It is assumed that the object Ma to be measured is selected and discharged by combination weighing. The weight W1 which is the first weighing value of the weighing hopper 10 ₁ at this time is measured in the state of the zero point error WE1 and is represented by the following equation. W1 = Wb + Wc + WE1 (5) At this time, the supply from the pool hopper 8 ₁ to the weighing hopper 10 ₁ is similarly stopped. Next, FIG.
In (C), the object Mk to be weighed is put into the storage chamber 72 ₁ , and the weight W2 which is the second weighing value of the weighing hopper 10 ₁ is measured. W2 = Wk + Wb + Wc + WE1 (6) From these equations (5) and (6), WH without WE3 can be obtained. Wk = W2-W1 (7)

Next, in FIG. 4D, the object to be weighed Mb is
Is selected and discharged, the weight W3 which is the third measured value of the weighing hopper 10 ₁ is measured. W3 = Wk + Wc + WE1 (8) At this time, the supply from the pool hopper 8 ₁ to the weighing hopper 10 ₁ is similarly stopped. Next, FIG.
In (E), the object Mm to be weighed is put into the storage chamber 74 ₁ and the weight W4 as the fourth measured value of the weighing hopper 10 ₁ is measured. W4 = Wk + Wm + Wc + WE1 (9) From these equations (8) and (9), Wm that does not include WE1 can be obtained. Wm = W4 -W3 (10)

Next, referring to FIG. 4 (F), the object Mc to be weighed is
Is selected and discharged, the weight W of the weighing hopper 10 ₁
5 is measured. W5 = Wk + Wm + WE1 (11) When the equations (7) and (10) are substituted into the equation (11), the zero-point set value WE3 is expressed as the following equation. WE1 = W5-Wk-Wm = W5- (W2-W1)-(W4-W3) The first zero point setting means 38 sets this zero point error WE1 as a new zero point correction value (zero point setting by alternate discharge).

Next, FIG. 5 shows the configuration of the control unit of the combination weighing device according to another embodiment of the present invention. In addition to FIG. 2, this control unit further includes a second zero point setting means 62, a third zero point setting means 64, a priority operation control means 66, an error discharge command means 68, and a forced discharge command means 70.

In this device, the combination calculation means (CP
U) 36 has a built-in counter that counts the number of times each weighing hopper has participated in the combination, and the count value of one of the weighing hoppers reaches the predetermined first count value that requires zero resetting. Then, the weighing hopper is recognized as a specific weighing hopper, and the "alternate discharge" system of FIG. 2 is entered. In this state, when the combination of the storage chambers is not selected within the allowable range of the target weight, that is, when an error occurs, the combination calculation means (CPU) 36 gives the error selection signal C2 to the priority operation control means 66. To be In response to the error selection signal C2, the priority operation control means 66 operates the error ejection command means 68 in preference to the output of the combination selection signal C1 in the "alternate ejection" system. The error discharge command means 68 outputs an error discharge opening command signal S2 to the second gate drive means 60 to open all the storage chambers 20 and 22 of the specific weighing hopper 10, which is the zero point setting target, and to close the storage chambers. Discharge the sample. At this time, the combination calculation is not performed. And the second
The zero point setting means 44 sets a new zero point correction value based on the weight detection signal indicating the weight of the weighing hopper 10 from which the object to be weighed has been discharged (zero point setting due to error discharge).

Further, the first and second zero point setting means 3
When a new zero point correction value is not set by 8, 62 and the counter becomes the second count value exceeding the first count value, and it is not preferable that the zero point is further delayed, the combination calculation means (CPU) ) 36, the forced selection signal C3 is given to the priority operation control means 66. The priority operation control means 66 activates the forced ejection command means 70 by the forced selection signal C3 in preference to the combination selection signal C1 and the error selection signal C2. Forced discharge command means 7
0 outputs the forced discharge opening command signal S3 to the second gate driving means 60 to open all the storage chambers 20 and 22 of the specific weighing hopper 10 and discharge the objects to be weighed.
At this time, similarly, the combination calculation is not performed. Then, the third zero point setting means 64 sets a new zero point correction value based on the weight detection signal indicating the weight of the weighing hopper 10 from which the object to be weighed is discharged (zero point setting by forced discharge).

In this way, this apparatus can surely execute the zero point reset by the "error discharge" and the "forced discharge" even when the zero point setting by the "alternate discharge" is not performed at an appropriate timing.

It should be noted that only "alternate discharge" and "error discharge" may be performed in this priority order and "forced discharge" may not be performed.

Note that the objects to be weighed that have been subjected to error discharge or forced discharge are defectively discharged from the defective discharge chute 52 by switching the sorting gate 50 in FIG. Normally, the defective discharge chute 52 is closed, and the objects to be weighed are discharged toward the packing machine discharge chute 54.

[0038]

[0039]

As described above, the invention of claim 1 or 2 is as follows.
According to the report, the number of specific weighing hoppers for which the zero point is to be set
In the storage room, the objects to be weighed are alternately supplied and discharged.
Occasionally, each time the object to be weighed is supplied or discharged
The weight detection signal of the hopper is taken in as the measured value, and these
Reset the zero correction value by performing a predetermined calculation based on the measured value.
When the combination within the allowable range based on the target value is not selected in the 1st process, the "alternate discharge" of the 1st process
Based on the weight of the weighing hopper after "error-discharging" all the storage chambers of the specific weighing hopper for which the zero is set, prioritizing the second step over setting a new zero correction value Set a new zero point correction value. Therefore, the
Even if the zero point setting by the "alternate discharge" in one process is not performed at an appropriate timing, the zero point resetting is surely performed by the "error discharge".

Further, according to the invention of claim 3 or 4, the "alternate discharge" of the invention of claim 1 or 2 or
When a predetermined zero point setting request timing is reached for a specific weighing hopper without setting a new zero point correction value due to "error discharge" , all storage chambers of the specific weighing hopper for which the zero point is set are "forced". Then, a new zero correction value is set based on the weight of the weighing hopper. Therefore, the zero point resetting is surely performed by the "forced discharge" at the predetermined zero point setting timing.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic side view of a combination weighing device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a control unit of the combination weighing device.

FIG. 3 is a schematic diagram showing a state in which a zero correction value is set.

FIG. 4 is a schematic diagram showing a state in which a zero correction value is set.

FIG. 5 is a diagram showing a configuration of a control unit of a combination weighing device according to another embodiment of the present invention.

[Explanation of symbols]

8 ₁ to 8 _N ... pool hoppers, 10 ₁ ~10 _N ... weighing hoppers, 12 ₁ ~12 _N ... weight detector, 16 ₁ ~16 _{N, 1}
8 ₁ to 18 _N , 24 _{1 to} 24 _N , 26 _{1 to} 26 _N ... Ejection gate, 34 ... Signal sequential acquisition means, 36 ... Combination calculation means (CPU), 38 ... First zero point setting means, 54 ... Initial zero point Setting means, 56 ... Zero setting request generating means, 58 ... First
Gate driving means, 60 ... Second gate driving means.

Claims (4)

(57) [Claims] 1. A plurality of storage chambers provided in each weighing hopper
Selectively supplies the objects to be weighed, weighs, and stores
Allowance based on target value by combining and calculating the weight of each room
Select a combination of storage compartments within the range and set them
A combination weighing method that opens and discharges the objects to be weighed
, One storage room for the specific weighing hopper for which the zero point is set.
When the objects to be weighed are discharged from the pool hopper,
After prohibiting the supply of the objects to be weighed to the delivery room,
Import the measured weight of the object to be weighed in the delivery room as the first measured value
Then, measure the other storage chamber of the above specific weighing hopper.
From the pool hopper with the items stored,
Supply the objects to be weighed into one storage room, and each storage room at that time
The total measured weight of the objects stored in the
And the object to be weighed is stored in the one storage chamber.
In this state, weighed items from other storage chambers can be selected by selecting the combination.
After discharging the items, from the pool hopper to the other storage room above
Prohibit the supply of the objects to be weighed to the
Import the measured weight of the object to be measured as the third measurement value, and if there is another storage room, move the above storage room up.
As one storage room, repeat the above loading operation
Based on these 1st to 3rd and 4th and later measured values,
1st process of setting a new zero correction value by performing a predetermined calculation by
However, if a combination within the allowable range is not selected, all storage chambers of the specific weighing hopper are opened to discharge the objects to be weighed, and then a new weight is calculated based on the empty weight of the weighing hopper. And a second step of setting a zero-point correction value, and when the combination within the allowable range is not selected during the execution of the first step, the combination weighing method preferentially executes the second step. 2. A weighing hopper having a plurality of storage chambers and a weight detection signal for weighing the objects to be weighed stored in the storage chambers.
The weight detector that outputs the signal and the objects to be weighed are selectively supplied to the storage chambers of the weighing hopper.
A pool hopper to be supplied and the weight detection signal are combined and calculated, and the target value is used as a reference.
Select a combination of storage rooms that is within the allowable range, and select
Combination calculation means for outputting weighing hopper opening command signal
And open the storage room of the weighing hopper based on the opening command signal.
Combination weighing device having opening / closing means for discharging the object to be weighed
In the storage, is it one storage room for the specific weighing hopper for which the zero point is set?
When the objects to be weighed are discharged from the pool hopper,
After prohibiting the supply of the objects to be weighed to the delivery room,
Import the measured weight of the object to be weighed in the delivery room as the first measured value
Then, measure the other storage chamber of the above specific weighing hopper.
From the pool hopper with the items stored,
Supply the objects to be weighed into one storage room, and each storage room at that time
The total measured weight of the objects stored in the
And the object to be weighed is stored in the one storage chamber.
In this state, weighed items from other storage chambers can be selected by selecting the combination.
After discharging the items, from the pool hopper to the other storage room above
Prohibit the supply of the objects to be weighed to the
Import the measured weight of the object to be measured as the third measurement value, and if there is another storage room, move the above storage room up.
As one storage room, repeat the above loading operation
A signal sequential acquisition means for acquiring the fourth and subsequent measurement values, and based on these first to third and fourth measurement values
First, the predetermined calculation is performed to set a new zero point correction value.
Zero point setting means is further provided, and when a combination within the allowable range is not selected, an error discharge opening command signal for opening all storage chambers of a specific weighing hopper and discharging the object to be measured is opened and closed. Means for outputting to the means, a second zero point setting means for setting a new zero point correction value based on the empty weight of the specific weighing hopper from which the object to be weighed is discharged, and within the allowable range. If no combination of
A combination weighing device comprising: an error discharge command means and a priority operation control means for operating the second zero point setting means in preference to setting a new zero point correction value by the zero point setting means. 3. The combination weighing method according to claim 1 , further comprising: opening all storage chambers of a specific weighing hopper at a predetermined zero point setting request timing to discharge the objects to be weighed, and then discharging the weighing hopper. When a predetermined zero point setting request timing is reached for the specific weighing hopper in a state in which the third step for setting a new zero point correction value based on the weight is provided and the first step and the second step are not executed , A combination weighing method which preferentially executes the third step. 4. The combination weighing device according to claim 2 , further comprising: forced discharge command means for discharging all objects to be weighed by opening all storage chambers of a specific weighing hopper at a predetermined zero point setting request timing. Third zero point setting means for setting a new zero point correction value based on the weight of the specific weighing hopper from which the object has been discharged, and the priority operation control means includes new zero points by the first and second zero point setting means. A combination weighing device characterized in that when the predetermined zero point setting request timing is reached for the specific weighing hopper without setting the correction value, the forced discharge command means and the third zero point setting means are preferentially operated. .