JP6708265B2 - electronic balance - Google Patents

Description

The present invention relates to an electronic balance for measuring the mass of a measuring object placed on a placing part.

The electronic balance includes a mounting part on which the measurement target is mounted, and a load detection part that detects the load of the measurement target mounted on the mounting part. In the electronic balance, the mass of the measuring object is measured based on the electric signal from the load detecting section in a state where the measuring object is placed on the placing section.

In such an electronic balance, the electric signal from the load detection unit may be unstable due to the influence of static electricity or the like. Specifically, the fluctuation range (variation) of the waveform indicating the electronic signal from the load detection unit becomes large, and it may be difficult to detect the signal value with a certain accuracy.
Therefore, an electronic balance provided with a static eliminator for removing static electricity of a measurement target has been proposed (for example, refer to Patent Document 1 below).

In the electronic balance described in Patent Document 1, the static eliminator is operated while the measurement target is placed on the placement part. Then, the load detection unit outputs a stable electric signal based on the measurement target object with the static electricity removed. In the electronic balance, the mass of the measuring object is measured based on this electric signal.

JP, 2016-173308, A

The conventional electronic balance as described above has a problem in that the static elimination operation may not be properly performed. Specifically, in the electronic balance, when the detection signal from the load detection unit is not stable, the cause may be the influence of static electricity or the influence other than static electricity. The effects other than static electricity include, for example, when the user touches the electronic balance to cause vibration, or when the temperature difference between room temperature and the electronic balance causes convection in the electronic balance. ..

When the cause of the unstable detection signal from the load detection unit is the influence of static electricity, it is necessary to perform the static elimination operation until the detection signal becomes stable. On the other hand, if the cause of the unstable detection signal from the load detector is something other than static electricity, wait until the vibration generated in the electronic balance subsides, or check the temperature difference between room temperature and the electronic balance. It is necessary to take measures such as doing.

Here, it is difficult for the user to visually check the display unit or the like to distinguish whether the cause of the unstable detection signal is the influence of static electricity or the influence other than static electricity. Therefore, if the cause of the unstable detection signal is the influence of static electricity, the user may mistakenly consider the cause to be an influence other than static electricity and take the above-mentioned action, or the detection signal may not be stable. Even if the influence is other than static electricity, the user may mistakenly determine the cause to be the influence of static electricity and uselessly perform static elimination operation.
The present invention has been made in view of the above circumstances, and an object thereof is to provide an electronic balance that can accurately determine the cause of a detected load value that is not stable.

(1) The electronic balance according to the present invention includes a mounting unit, a load detection unit, a static eliminator, a static elimination processing unit, and a determination processing unit. An object to be measured is placed on the placing unit. The load detection unit detects the load of the measurement target placed on the placement unit. The static eliminator removes static electricity from the measurement target placed on the placement unit. The static elimination processing unit controls the operation of the static eliminator. The determination processing unit, in the state where the measurement object is placed on the placement unit, by the control of the static elimination processing unit, when static elimination by the static eliminator is performed, the load detection before and after performing static elimination Based on the change in the swing width of the load detected by the unit, it is determined whether the swing width is due to static electricity.

When the value of the load detected by the load detection unit is not stable when the object to be measured is placed on the placement unit, there is a fluctuation (variation) in the value of the detected load. When the cause of the fluctuation in the detected load value is the influence of static electricity, static electricity is removed by removing the static electricity by the static eliminator, and the fluctuation range changes (decreases). On the other hand, when the cause of the fluctuation in the detected load value is an influence other than static electricity, the fluctuation of the load does not change even if the static eliminator performs static elimination.

According to the above-described configuration, the determination processing unit performs static elimination by the static eliminator, and based on the change in the swing width of the load detected by the load detection unit before and after the static elimination, the swing width is due to static electricity. Or not.

Therefore, when the value of the load detected by the load detection unit has a fluctuation (unstable) due to the influence of static electricity, it can be accurately determined that the cause is the influence of static electricity. Further, when the value of the load detected by the load detection unit has a fluctuation range due to an influence other than static electricity, it can be accurately determined that the cause is an influence other than static electricity.

(2) Further, when the determination processing unit determines that the swing width of the load detected by the load detection unit is due to static electricity, the static elimination processing unit until the swing width becomes less than the threshold value, The static elimination by the static eliminator may be repeated.

When the static elimination operation is performed in the electronic balance, the static elimination time is preferably increased or decreased according to the amount of static electricity. However, in the static eliminator of the conventional electronic balance, a predetermined static elimination time (for example, 10 seconds) is usually set in advance, and if the signal is not stable in one static elimination operation (static elimination operation for 10 seconds), The static elimination operation (the static elimination operation for 10 seconds) was performed once. In that case, for example, even if the static elimination was originally completed in 15 seconds, since the static elimination operation was performed for 20 seconds, the extra static elimination operation was performed. Therefore, there is a problem that the working time of the electronic balance becomes long.
According to the configuration described above, when the swing range of the load detected by the load detection unit is due to static electricity, the static eliminator can be operated as much as necessary to remove the static electricity of the measurement target.
Therefore, it is possible to prevent the working time of the electronic balance from increasing.

(3) Further, the electronic balance may further include a storage unit. The storage unit stores the static elimination time until the swing width of the load detected by the load detection unit becomes less than the threshold value in association with the identification information of the measurement target.

With such a configuration, it is possible to store an appropriate static elimination time corresponding to a predetermined measurement target in the storage unit.

(4) Further, the electronic balance may further include a static elimination time prediction processing unit. The static elimination time prediction processing unit, when the determination processing unit determines that the swing width of the load detected by the load detection unit is due to static electricity, based on the change in the swing width, the swing width. The static elimination time until is less than the threshold is predicted.

According to such a configuration, the static elimination time prediction processing unit can predict an appropriate static elimination time for removing static electricity of the measurement target.

(5) Further, the electronic balance may further include a storage unit. The storage unit stores the static elimination time predicted by the static elimination time prediction processing unit in association with the identification information of the measurement target.

With such a configuration, it is possible to store an appropriate static elimination time corresponding to a predetermined measurement target in the storage unit.

(6) Further, the static elimination processing unit may perform static elimination by the static eliminator based on the load of the measurement object being detected by the load detector.

With such a configuration, it is possible to automatically perform static elimination by the static eliminator based on the fact that the measurement target object is placed on the placing section.
Therefore, it is possible to omit the work of the user operating the operation unit to start the static elimination operation.

(7) Further, the electronic balance may further include an identification information reading unit and a charge removal time reading unit. The identification information reading unit reads the identification information of the measurement target placed on the placing unit. The static elimination time reading unit reads the static elimination time corresponding to the identification information read by the identification information reading unit from the storage unit. The static elimination processing unit may perform static elimination of the measurement target by the static eliminator for the static elimination time read by the static elimination time reading unit.

With such a configuration, it is possible to read the appropriate static elimination time corresponding to the measurement target placed on the placement unit from the storage unit. Then, it is possible to eliminate the static electricity of the measurement target for the appropriate static elimination time.

According to the present invention, the determination processing unit performs static elimination by the static eliminator, and based on the change in the swing width of the load detected by the load detection unit before and after the static elimination, is the swing width caused by static electricity? Determine whether or not. Therefore, when the value of the load detected by the load detection unit has a fluctuation range due to the influence of static electricity, it can be accurately determined that the cause is the influence of static electricity. Further, when the value of the load detected by the load detection unit has a fluctuation range due to an influence other than static electricity, it can be accurately determined that the cause is an influence other than static electricity.

It is a block diagram showing an example of composition of an electronic balance concerning a 1st embodiment of the present invention. It is a graph which showed the time change of the value of the load of the measuring object detected by the load primary detecting element. 3 is a flowchart showing an example of processing by the control unit of FIG. 1, showing processing from when a user operates the operation unit to when the charge removal time is stored in the storage unit. 3 is a flowchart showing an example of processing by the control unit of FIG. 1, showing processing from reading of the identification information of the measurement object to execution of the static elimination operation. It is a block diagram showing an example of composition of an electronic balance concerning a 2nd embodiment of the present invention. 6 is a flowchart showing an example of processing by the control unit of FIG. 5, showing processing from the detection of the load of the measurement object to the storage of the charge removal time in the storage unit.

1. Overall Configuration of Electronic Balance FIG. 1 is a block diagram showing a configuration example of an electronic balance according to a first embodiment of the present invention. This electronic balance is for measuring the mass of the measuring object W, and is provided with a mounting unit 1, a load detection unit 2, a static eliminator 3, an operation unit 4, a display unit 5, an identification information reading unit 6, and a storage unit. 7 and a control unit 8 and the like.

The mounting unit 1 is composed of, for example, a weighing dish, and the measurement object W is mounted on the upper surface thereof. In the electronic balance according to the present embodiment, in addition to the sample made of powder, various measurement objects W can be placed on the placing unit 1 to measure the mass. The periphery of the mounting portion 1 is covered with, for example, an openable/closable windshield case (not shown), and a weighing chamber is formed in the windshield case.

The load detection unit 2 detects the load of the measuring object W placed on the placing unit 1. Although not shown, in this example, the measurement object W is provided with an identification information holding unit that holds identification information for identifying the measurement object W such as a barcode or an IC tag.
By detecting the load received by the placement unit 1 from the measurement target W by the load detection unit 2, the mass of the measurement target W can be measured based on the load. As a method of detecting the load in the load detecting unit 2, an electromagnetic type or a load cell type can be exemplified.

When the load detection unit 2 is an electromagnetic type, for example, a magnet and a coil are provided in the load detection unit 2. In this case, an electric current is passed through the coil so that the electromagnetic force acts on the coil so that the load of the object W to be measured placed on the placing section 1 is balanced, and the object W to be measured is based on the current amount at that time. The load can be detected.

When the load detection unit 2 is of a load cell type, the strain detection unit 2 is provided with a flexure element formed of, for example, aluminum. In this case, when the measuring object W is placed on the placing part 1, the strain-generating body is bent, and the amount of the bending is detected as an electric signal by using a strain gauge or the like, and based on the electric signal. The load of the measuring object W can be detected. However, the load detection unit 2 is not limited to the electromagnetic type or the load cell type, and may be configured to detect the load by another detection method such as a tuning fork type.

The static eliminator 3 removes the static electricity of the measurement object W placed on the placement unit 1. Specifically, by spraying the ions generated in the static eliminator 3 onto the mounting unit 1, the static electricity of the measurement target W on the mounting unit 1 can be neutralized and removed without contact. However, the static eliminator 3 is not limited to the above-described configuration as long as it can remove static electricity accumulated in the measurement object W, and adopts a configuration that can remove static electricity in various other modes. can do.
The operation unit 4 is composed of, for example, a keyboard (switch).
The display unit 5 is composed of, for example, a liquid crystal display.

The identification information reading unit 6 is configured to read the identification information from the identification information holding unit associated with the measurement object W. The identification information reading unit 6 is composed of, for example, a bar code reader or an IC tag reader.

The storage unit 7 is composed of, for example, a hard disk or a RAM (Random Access Memory). The storage unit 7 stores a threshold value 71 and a plurality of static elimination information 72.

The threshold value 71 is information serving as a reference when the control unit 8 ends the operation of the static eliminator 3, and is stored in the storage unit 7 in advance. The threshold value 71 may be stored in the storage unit 7 based on the user's operation of the operation unit 4.

The static elimination information 72 is information on the static elimination time of the static eliminator 3, and includes identification information 721 and a static elimination time 722. The identification information 721 is information for identifying the measuring object W. The static elimination time 722 is information on the time for static elimination of the static eliminator 3. The identification information 721 and the static elimination time 722 are associated with each other.

The control unit 8 is configured to include, for example, a CPU (Central Processing Unit). The control unit 8 is electrically connected to the load detection unit 2, the static eliminator 3, the operation unit 4, the display unit 5, the identification information reading unit 6, the storage unit 7, and the like. In the present embodiment, the control unit 8 functions as the input reception unit 81, the charge removal time reading unit 82, the determination processing unit 83, the charge removal processing unit 84, the display processing unit 85, and the like by the CPU executing the program.

The input reception unit 81 receives an input of the operation content of the operation unit 4 by the user. In this example, the user operates the operation unit 4 to start the operation of the static eliminator 3. That is, the input receiving unit 81 receives an input for starting the operation of the static eliminator 3.
The static elimination time reading unit 82 reads the static elimination information 72 stored in the storage unit 7 based on the identification information read by the identification information reading unit 6.

The determination processing unit 83 determines, based on the detection signal of the load detection unit 2, whether or not static electricity is generated in the measuring object W placed on the placing unit 1. Specifically, when the value of the load (detection signal) detected by the load detection unit 2 has a fluctuation range (variation), the determination processing section 83 determines whether or not the fluctuation range is due to static electricity. To judge.

The static elimination processing unit 84 controls the operation of the static eliminator 3. Specifically, the static elimination processing unit 84 operates the static eliminator 3 based on the input acceptance unit 81 accepting the input. Further, the charge removal processing unit 84 operates the charge remover 3 based on the determination result of the determination processing unit 83, the detection signal of the load detection unit 2, and the threshold value 71 stored in the storage unit 7. Further, the charge removal processing unit 84 operates the charge remover 3 for a predetermined charge removal time based on the charge removal information 72 read by the charge removal time reading unit 82.
The display processing unit 85 controls the display on the display unit 5 based on the detection signal of the load detection unit 2 or the determination result of the determination processing unit 83.

2. Value of Load Detected by Load Detecting Section FIG. 2 is a graph showing changes with time of the load value of the measuring object W detected by the load detecting section 2. FIG. 2 shows the change over time in the value of the load when the measurement object W is charged with static electricity.

As shown in this graph, when the measurement object W is charged with static electricity, the load value of the measurement object W detected by the load detection unit 2 has a fluctuation range (variation). Specifically, a plurality of values different from the original load value A of the measuring object W are detected. In this graph, the swing width is the difference between the maximum value and the minimum value of the load for each predetermined time interval. This graph shows a state in which the swing width generated in the value of the load detected by the load detection unit 2 decreases as time passes as a result of the static electricity of the measurement object W being removed.

3. Control Operation of Control Unit FIG. 3 is a flowchart showing an example of a process performed by the control unit 8 and shows a process from when the user operates the operation unit 4 to when the charge removal time is stored in the storage unit 7. ing.

In this electronic balance, when the measurement target W is placed on the mounting unit 1, the identification information of the measurement target W is read by the identification information reading unit 6 and the load of the measurement target W is detected by the load detection unit 2. Detected by. In this example, it is assumed that the measurement object W that is charged with static electricity is placed on the placing unit 1. The display processing unit 85 causes the display unit 5 to display the value of the mass of the measuring object W based on the detection signal from the load detection unit 2. In this example, since the measurement target W is charged with static electricity, the value of the load (detection signal) detected by the load detection unit 2 has a large swing range as shown by B in FIG. Therefore, the display unit 5 displays an unstable value with a large shake amount.

Therefore, the user performs a predetermined operation on the operation unit 4 to start the operation of the static eliminator 3, such as pressing a static elimination button. When the operation unit 4 is operated, the input reception unit 81 receives an input signal from the operation unit 4 (YES in step S101).

Then, the static elimination processing unit 84 performs the operation of the static eliminator 3 once based on that the input reception unit 81 has received the input signal (the signal for starting the operation of the static eliminator 3) from the operation unit 4. (Step S102). In this example, the static elimination processing unit 84 operates the static eliminator 3 for several seconds as the operation of the static eliminator 3. Further, in FIG. 2, the timing at which the static elimination processing unit 84 operates the static eliminator 3 is represented as T ₁ .

At this time, the determination processing unit 83 determines whether or not the measurement target W is charged with static electricity before and after the timing T ₁ based on the change in the swing width of the load value detected by the load detection unit 2. It is determined whether or not the shake width is due to static electricity. Specifically, when the determination processing unit 83, which compares the amplitude of the load in front of the timing T _1, the amplitude of the load after the timing T _1, amplitude is small, It is determined that the cause of the fluctuation in the load value is the influence of static electricity, and when the fluctuation is almost unchanged or does not change, the cause of the fluctuation in the load value is the influence other than static electricity. It is determined that

In this example, than the load of the amplitude of the previous time T _1, since the amplitude of the load after the timing T ₁ is smaller (YES in step S103), determination processing section 83, load detection It is determined that the cause of the fluctuation in the load value detected by the unit 2 is the influence of static electricity (step S104).

Then, the static elimination processing unit 84 causes the static eliminator 3 to operate (re-static elimination) again (step S105). Further, the charge removal processing unit 84 reads the threshold value 71 from the storage unit 7, and while the fluctuation range of the load value detected by the load detection unit 2 is equal to or greater than the threshold value 71 (NO in step S106), the charge remover 3 is operated for a certain time. Operate repeatedly at intervals. In this example, the static elimination processing unit 84 operates the static eliminator 3 for a few seconds at regular time intervals, and the fluctuation range of the load value detected by the load detection unit 2 is at the timing indicated by T ₂ in FIG. It is less than the threshold value 71.

In this way, when the fluctuation range of the load value detected by the load detection unit 2 becomes less than the threshold value 71 (YES in step S106), the static elimination processing unit 84 ends the operation of the static eliminator 3. As a result, the static electricity of the measuring object W is removed, and the value indicating the mass of the measuring object W is displayed on the display unit 5 in a stable state.

The charge removal processing unit 84 stores the time (T ₂ −T ₁ ) until the fluctuation range of the load value detected by the load detection unit 2 becomes less than the threshold value 71 as the charge removal time 722 in the storage unit 7. At this time, the static elimination time 722 is stored in the storage unit 7 in association with the identification information of the measuring object W read by the identification information reading unit 6. The identification information at this time is the identification information 721.

Further, in the case of NO in step 103, that is, when the static eliminator 3 is operated once, when the fluctuation range of the value of the load detected by the load detection unit 2 does not substantially change or does not change, The determination processing unit 83 determines that the cause of the fluctuation in the load value detected by the load detection unit 2 is an influence other than static electricity (step S108).

Then, the display processing unit 85 displays, on the display unit 5, based on the determination result of the determination processing unit 83, that the value of the load detected by the load detection unit 2 has a fluctuation range due to an influence other than static electricity. (Step S109). As a result, the user who confirms this display can take appropriate measures such as waiting until the vibration generated in the electronic balance subsides or checking the temperature difference between the room temperature and the electronic balance. ..

FIG. 4 is a flowchart showing an example of the process performed by the control unit 8, and shows the process from the reading of the identification information of the measuring object W to the execution of the static elimination operation.
In the above description, the static elimination information 72 stored in the storage unit 7 is used as follows.

When the identification information reading unit 6 reads the identification information of the measurement target object W placed on the placing unit 1 and the identification information is stored as the identification information 721 in the storage unit 7 (step S201). The static elimination time reading unit 82 reads the static elimination time 722 corresponding to the identification information 721 (step 202).
Then, the static elimination processing section 84 operates the static eliminator 3 for the period of the static elimination time 722 to eliminate the static electricity of the measuring object W (step 203).

4. Action and Effect (1) According to the present embodiment, when the measurement object W is placed on the placement unit 1 of the electronic balance, the value of the load detected by the load detection unit 2 has a fluctuation range. In addition, when the static eliminator 3 performs the static elimination once, the determination processing unit 83 determines the swing width of the load value based on the change in the swing width of the load value detected by the load detection unit 2 before and after the static elimination operation. It is determined whether is caused by static electricity.

Therefore, when the value of the load detected by the load detection unit 2 has a fluctuation range due to the influence of static electricity, it can be accurately determined that the cause is the influence of static electricity. Further, when the value of the load detected by the load detection unit has a fluctuation range due to an influence other than static electricity, it can be accurately determined that the cause is an influence other than static electricity.

(2) According to the present embodiment, when the determination processing unit 83 determines that the cause of the fluctuation in the load value detected by the load detection unit 2 is the influence of static electricity (step S104), the static elimination processing unit 84 reads the threshold value 71 from the storage unit 7, and repeats the static eliminator 3 at regular time intervals until the fluctuation range of the load value detected by the load detection unit 2 becomes less than the threshold value 71. It is operated (step S105).

Therefore, when the fluctuation range of the load value detected by the load detection unit 2 is due to static electricity, the static eliminator 3 can be operated as necessary to remove the static electricity of the measurement object W.
Therefore, it is possible to prevent the working time of the electronic balance from increasing.

(3) According to the present embodiment, the storage unit 7 measures the time (T ₂ −T ₁ ) until the swing width of the load value detected by the load detection unit 2 becomes less than the threshold value 71. It is stored in the storage unit 7 in association with the identification information of the target object W.

Therefore, it is possible to store an appropriate static elimination time corresponding to a predetermined measurement object in the storage unit 7.

(4) According to the present embodiment, as a result of the identification information reading unit 6 reading the identification information of the measuring object W placed on the placing unit 1, the identification information is stored in the storage unit 7 as the identification information 721. If it is stored as (step S201), the static elimination time reading unit 82 reads the static elimination time 722 corresponding to the identification information 721 (step 202). Then, the static elimination processing section 84 operates the static eliminator 3 for the period of the static elimination time 722 to eliminate the static electricity of the measuring object W (step 203).

Therefore, an appropriate static elimination time corresponding to the measuring object W placed on the placing unit 1 is stored in the storage unit 7
Can be read from. Then, the measurement object W can be destaticized for the appropriate destaticization time.

5. Second Embodiment Hereinafter, an electronic balance according to a second embodiment of the present invention will be described with reference to FIGS. 5 and 6. In addition, about the same structure and method as 1st Embodiment, description is abbreviate|omitted by using the same code|symbol etc. as above.

As shown in FIG. 5, the electronic balance of the second embodiment is significantly different from the first embodiment in that the configuration of the operation unit 4 in the electronic balance of the first embodiment is not required.

(1) Overall Configuration of Electronic Balance Specifically, in the electronic balance of the second embodiment, the control unit 8 causes the static elimination time reading unit 82, the determination processing unit 83, and the static elimination processing unit to be executed by the CPU executing the program. 84, the display processing part 85, and the static elimination time prediction processing part 86. That is, in the electronic balance of the second embodiment, the control unit 8 does not have the input receiving unit 81, but has the static elimination time prediction processing unit 86 as a newly functioning processing unit.

The static elimination time prediction processing unit 86 predicts an appropriate static elimination time based on the determination result of the determination processing unit 83 and the value of the load detected by the load detection unit 2. Specifically, in the static elimination time prediction processing unit 86, the determination processing unit 83, based on the change in the swing width of the value of the load detected by the load detection unit 2, until the swing width becomes less than a predetermined threshold value. Predict the static elimination time.

(2) Control Operation of Control Unit FIG. 6 is a flowchart showing an example of the process performed by the control unit 8. From the detection of the load of the measuring object W to the storage of the static elimination time. The processing is shown.

In the electronic balance, when the electrostatically charged measurement target W is placed on the mounting unit 1, the identification information of the measurement target W is read by the identification information reading unit 6 and the load of the measurement target W is applied. It is detected by the detection unit 2 (YES in step S301).

Then, the static elimination processing unit 84 performs the operation of the static eliminator 3 once based on the fact that the load detector 2 detects the load (step S302). The contents of the operation of the static eliminator 3 under the control of the static elimination processing unit 84 are the same as those in the first embodiment.

Then, similarly to step 103 of the first embodiment, the determination processing unit 83 is based on the fact that the swing range of the load is small before and after the static elimination by the static eliminator 3 (YES in step S103), and the load detection unit. It is determined that the cause of the fluctuation in the load value detected by 2 is the influence of static electricity (step S304).

Then, the static elimination time prediction processing unit 86 predicts the static elimination time until the swing width becomes less than the predetermined threshold value based on the change (decrease) in the swing width of the load value detected by the load detection unit 2 ( Step S305). Specifically, the static elimination time prediction processing unit 86 is represented by a line with a predetermined slope that represents a decrease in the shake width, based on information about the shake width value (information about the maximum value and the minimum value) at a predetermined time. Derive a function (a function containing a given variable). Then, the static elimination time prediction processing unit 86 calculates the time until the swing width becomes less than the threshold value, based on the function. The threshold value at this time may be stored in the storage unit 7 as in the first embodiment.
Then, the static elimination processing section 84 operates the static eliminator 3 for the static elimination time predicted by the static elimination time prediction processing section 86 to eliminate the static electricity of the measuring object W (step 306).

When the operation of the static eliminator 3 ends, the display processing unit 85 causes the display unit 5 to display a value indicating the mass of the measuring object W based on the stable detection signal detected by the load detection unit 2 (step S307). .. Further, the static elimination time prediction processing unit 86 stores the predicted static elimination time in the storage unit 7 as the static elimination time 722 (step S308). At this time, the static elimination time 722 is stored in the storage unit 7 in association with the identification information of the measuring object W read by the identification information reading unit 6. The identification information at this time is the identification information 721.

If NO in step 303, as in steps S108 and 109 of the first embodiment, the determination processing unit 83 determines that the value of the load detected by the load detection unit 2 has a fluctuation range due to electrostatic discharge. (Step S309), and the display processing unit 85 displays on the display unit 5 that the value of the load detected by the load detection unit 2 has a fluctuation range due to the influence other than static electricity (step S309). Step S310).

Note that the same processing as steps 201 to 203 in FIG. 4 of the first embodiment is also executed in the second embodiment. In this case, the information stored in the storage unit 7 in step 308 is used.

(3) Effects of Second Embodiment (3-1) In the second embodiment, in the electronic balance, the control unit 8 has the static elimination time prediction processing unit 86 as a newly functioning processing unit. When the determination processing unit 83 determines that the cause of the fluctuation in the load value detected by the load detection unit 2 is the influence of static electricity, the static elimination time prediction processing unit 86 determines the fluctuation (step S304). Based on the change in width, the static elimination time until the shake width becomes less than the threshold value is predicted (step S305).

Therefore, the static elimination time prediction processing unit 86 can predict an appropriate static elimination time for removing the static electricity of the measurement object W.

(3-2) In addition, in the second embodiment, the charge removal time predicted by the charge removal time prediction processing unit 86 is stored in the storage unit 7 as the charge removal time 722 (step S308). At this time, the static elimination time 722 is stored in the storage unit 7 in association with the identification information of the measuring object W read by the identification information reading unit 6.

Therefore, it is possible to store an appropriate static elimination time corresponding to a predetermined measurement object in the storage unit.

(3-3) Further, in the second embodiment, the static elimination processing unit 84 performs the operation of the static eliminator 3 based on the fact that the load detection unit 2 detects the load (step S302).

Therefore, it is possible to automatically perform static elimination by the static eliminator 3 based on the fact that the measuring object W is placed on the placing unit 1.
As a result, it is possible to omit the work of the user operating the operation unit to start the static elimination operation.

6. Modified Example In the above-described first embodiment, when the determination processing unit 83 determines that the cause of the swing width in the value of the load detected by the load detection unit 2 is the influence of static electricity, the swing width is It has been described that the operation of the static eliminator 3 is automatically repeated at a constant time interval until it becomes less than the threshold value. However, in the first embodiment, when the determination processing unit 83 determines that the cause of the fluctuation in the load value detected by the load detection unit 2 is the influence of static electricity, the control of the display processing unit 85 is performed. The display unit 5 may display a message to prompt (propose) the static elimination operation. In this case, when the user performs a predetermined operation to operate the static eliminator 3 on the operation unit 4, the static eliminator processing unit 84 controls the static eliminator 3 to start operating. At this time, it is preferable that the display of the display unit 5 under the control of the display processing unit 85 be continuously performed until the swing width of the load value detected by the load detection unit 2 becomes less than the threshold value.

DESCRIPTION OF SYMBOLS 1 Placement part 2 Load detection part 3 Static eliminator 6 Identification information reading part 8 Control part 71 Threshold value 72 Static charge elimination information 82 Static charge time reading part 83 Judgment processing part 84 Static charge processing part 86 Static charge time prediction processing part 721 Identification information 722 Static charge time

Claims (7)

A mounting part on which the measuring object is mounted,
A load detection unit that detects the load of the measurement target placed on the placement unit,
A static eliminator that eliminates static electricity of the measurement target placed on the placement unit,
A static eliminator that controls the operation of the static eliminator,
With the object to be measured placed on the placement unit, by the control of the static elimination processing unit, when static elimination is performed by the static eliminator, the load detected by the load detection unit before and after performing static elimination. An electronic balance comprising: a determination processing unit that determines whether or not the swing width is due to static electricity based on a change in the swing width. When the determination processing unit determines that the swing width of the load detected by the load detection unit is due to static electricity, the static elimination processing unit performs static elimination by the static eliminator until the swing width becomes less than a threshold value. The electronic balance according to claim 1, wherein the above steps are repeated. The storage unit is further provided that stores a static elimination time until the swing width of the load detected by the load detection unit becomes less than the threshold value in association with the identification information of the measurement target. Electronic balance. When the determination processing unit determines that the swing width of the load detected by the load detection unit is due to static electricity, based on the change in the swing width, static elimination until the swing width becomes less than a threshold value The electronic balance according to claim 1, further comprising a static elimination time prediction processing unit that predicts time. The electronic balance according to claim 4, further comprising a storage unit that stores the static elimination time predicted by the static elimination time prediction processing unit in association with the identification information of the measurement target. The electronic balance according to claim 1, wherein the static elimination processing unit performs static elimination by the static eliminator based on the load of the measurement target being detected by the load detection unit. An identification information reading unit that reads the identification information of the measurement target placed on the placing unit,
A static elimination time reading unit that reads the static elimination time corresponding to the identification information read by the identification information reading unit from the storage unit;
The electronic balance according to claim 3, wherein the static elimination processing unit removes static electricity from the measurement target by the static eliminator for the static elimination time read by the static elimination time reading unit.

Images