JP6223861B2 - Meter - Google Patents

Description

  The present invention relates to a measuring instrument. In particular, the present invention relates to a weight signal filtering process of a weighing device in which a quantitative weighing (for example, packing) of an object to be weighed is performed.

  In a measuring instrument, also called a digital scale, a filter that assumes a fundamental vibration of several Hz that can be generally regarded as the natural frequency of the measuring instrument itself is fixedly incorporated. The weighing instrument includes an amplifier that amplifies the weight signal of the weight sensor, an analog filter that removes a high-frequency noise signal included in the weight signal, and an A / D converter that A / D converts the analog weight signal. That is, the analog weight signal is digitized by the A / D converter at sampling time intervals, and is read into the arithmetic circuit via the I / O circuit in time series as the sampling weight signal.

  Here, a moving average calculation filter that best attenuates the natural vibration of the measuring instrument is provided inside the calculation circuit, and the moving weighted sampling weight signal is displayed as a weight value. Such a moving average calculation filter is described in Patent Documents 1 and 2, and various improvements for the moving average calculation filter have already been proposed.

  For example, Patent Document 3 describes that a filter constant that is different in stages in the increasing / decreasing direction is provided in an arithmetic circuit of a measuring instrument, centering on a filter constant having a standard characteristic in a standard environment. Then, it has been proposed to provide a filter constant manual changing means capable of manually selecting the filter constant on the operation unit of the measuring instrument.

  In Patent Document 4, the CPU functions as a plurality of digital filters having characteristics capable of removing noise signals having different frequencies, and also functions as a filter selector that selects one of the output signals of each filter. An example is given.

JP 62-280625 A Japanese Patent Laid-Open No. 3-170031 JP 2006-78410 A JP 2003-207387 A

  In general, a combination weigher is known as a device for taking out a combination of objects to be weighed close to a target weight. A combination weigher is a type of weighing device that has a plurality of weighing instruments (balances) and can perform a combined operation of the weights of objects to be weighed by the weighing machines. In combination calculation, the combined weight of the objects to be weighed by the combination is closest to the target weight of the objects to be weighed (but not lower than the target weight) and within the appropriate range of the target weight (the upper limit value of the target weight and the target weight) A combination of measuring instruments is selected. The batch (lumb) of the objects to be weighed on the weighing machine thus selected is taken out by an appropriate method. Combination weighers are classified into three types: fully automatic, semi-automatic, and manual, depending on the method of loading the objects to be weighed and the method of taking out the objects from the weigher. Yes. In the fully automatic combination weigher, the input of the object to be weighed into the measuring instrument and the removal of the object to be weighed from the measuring instrument are all performed automatically. In the semi-automatic combination weigher, only an object to be weighed into a weighing instrument (or a corresponding supply hopper) is manually operated by an operator. In the manual combination weigher, both the input of the object to be weighed into the measuring instrument and the removal of the object to be weighed from the measuring instrument are performed manually by the operator.

  With the combination weighers described above, the weight of the object to be weighed can be displayed, but it is not possible for an operator to put or place the object to be weighed on an individual weighing instrument while viewing the weight display during operation. Absent.

  On the other hand, depending on the form of the object to be weighed (for example, a product that is difficult to automatically supply to the measuring instrument, a product that has an irregular shape, etc.) or the amount of the object to be weighed, the above combination weigher may not be used. In some cases, it may be preferable for an operator to manually select combinations of objects to be weighed that fall within an appropriate amount range of the objects to be weighed using a single weighing instrument while visually checking the display on the display unit.

  In this case, control of the response speed of display on the display unit is considered to be important for improving the efficiency of the operator's weighing work. However, in the conventional example, improvement in the efficiency of the weighing work in which the operator manually performs quantitative packing of the objects to be weighed while visually checking the display on the display unit has not been sufficiently studied. That is, the aspect of the aspect of the present invention is that the response speed of display on the display unit is changed according to the weight of the object to be weighed on the placement unit. As far as the present inventor is aware, there is no conventional example.

  One aspect of the present invention has been made in view of such circumstances, and in comparison with the prior art, the efficiency of weighing work in which an operator manually performs quantitative packing of objects to be weighed while visually checking the display on the display unit. An object of the present invention is to provide a measuring instrument capable of improving the above.

  In order to solve the above-described problem, a measuring instrument according to one aspect of the present invention is configured to follow the increase / decrease in the weight of the weighing object on the placing unit on which the weighing object is placed, and the weighing object on the placing part. A display unit that sequentially displays weight or a deviation of the weight from a predetermined weight value, and a controller that outputs a weight display value or a deviation display value on the display unit, The amount of change from the weight of the object to be weighed placed on the previous placement unit at the time prior to the start of the weighing operation of the approximate weight of the object to be weighed on the entry unit is outside the predetermined weight range (however, the weighing operation starts (Excluding the weight range corresponding to the vicinity of the weight of the weighing instrument at the previous time)), the weight that changes following the increase / decrease of the weight of the object to be weighed compared to the case in the predetermined weight range Increase the response speed of display or deviation display.

  As a result, when the above-mentioned amount of change in the approximate weight of the object to be weighed is outside the predetermined weight range when the operator manually performs the quantitative filling of the object to be weighed while visually observing the display on the display unit. Can increase the response speed of the weight display or the deviation display in accordance with the increase / decrease in the weight of the object to be weighed placed on the placing part, so that the operator can quickly identify the actual change amount of the object to be weighed. Therefore, the efficiency of the weighing work can be improved. Moreover, when this variation | change_quantity is in the predetermined weight range, flickering of these displays can be suppressed by making the response speed of a weight display or a deviation display slow. Therefore, the weighing work can be performed with high accuracy.

  According to one aspect of the present invention, it is possible to obtain a measuring instrument capable of improving the efficiency of a weighing operation in which a worker manually performs quantitative packing of an object to be weighed while visually checking the display on the display unit.

Drawing 1 is a figure showing an example of a measuring instrument of an embodiment. FIG. 2 is a flowchart illustrating an example of the operation of the measuring instrument according to the embodiment. Drawing 3 is a figure showing an example of a display by a measuring instrument of an embodiment. Drawing 4 is a figure showing an example of a measuring instrument of modification 1 of an embodiment.

(Embodiment)
[Background to obtaining this embodiment]
The present inventor has earnestly studied to improve the efficiency of the weighing work in which the operator manually performs quantitative packing of the objects to be weighed while observing the display on the display unit, and has obtained the following knowledge. Here, the case where the addition weighing method is adopted as the weighing operation will be described as an example.

  The degree of flickering of the weight display is affected by the magnitude of the amplitude of vibration noise remaining in the weight signal after filtering. In other words, the vibration noise included in the weight signal of the measuring instrument includes the influence of wind that is difficult to specify the frequency in addition to the basic vibration. Further, the period of the fundamental vibration that actually occurs during use does not always coincide with the time for obtaining the average value of the moving average calculation filter.

  Excluding noise with a period close to the average value calculation time or a period of an integer from the attenuation characteristic of the moving average calculation filter, in general, the longer the average value is calculated, the longer the noise attenuation of the weight signal. The effect is great. That is, the greater the number of sampling data for moving average calculation, the greater the noise attenuation effect of the weight signal. At the same time, the larger the number of sampling data, the slower the output response of the filter. Therefore, when the number of sampling data is increased, the response speed of the weight display based on the output of the filter becomes slow, but the flicker of the weight display is less likely to occur. On the other hand, if the number of sampling data is reduced, flickering of the weight display is likely to occur, but the response speed of the weight display based on the output of the filter is increased by increasing the response of the filter output.

  By the way, the weighing instrument sets an upper limit value and a lower limit value of the weight of the object to be weighed, and performs the quantitative packing (for example, packing) of the object to be weighed by setting the weight range of the object to be weighed between them as an appropriate range. May be. In this case, conventionally, the filter processing is performed with the noise attenuation effect of the weight signal constant regardless of the weight of the object to be weighed. For this reason, when the noise attenuation effect of the weight signal is relatively weak, the weight display changes quickly at the initial stage where the object to be weighed starts to be placed on the placement unit, but at the final stage close to the appropriate amount range, the weight display is performed. Flickering easily occurs. When the noise attenuation effect of the weight signal is relatively strong, the waiting time of the operator increases at the initial stage where the object to be weighed is started to be placed on the mounting part, due to a decrease in the response speed of the weight display. In the final stage close to, flickering of weight display can be suppressed.

  By the way, the present inventor, in the quantitative stuffing work of the objects to be weighed, when the operator places the objects to be weighed in order on the placement part of the weighing instrument, if the weight of the objects to be weighed is close to the appropriate range, It was found that only the approximate weight was confirmed in other cases.

  For example, the operator first places an object that is clearly lighter than the lower limit of the appropriate amount range of the object to be measured on the mounting table, and checks the approximate weight of the object to be measured on the display unit. Next, an object to be weighed is empirically selected whose total weight of the object to be weighed is still slightly lighter than the lower limit value of the appropriate amount range of the object to be weighed, and this is additionally placed on the mounting table. Bring the total weight of the sample close to the appropriate range for the item to be weighed. Finally, fine adjustment is performed so that the total weight of the objects to be weighed falls within the applicable range of the objects to be weighed.

  In such weighing work, the operator promptly determines the approximate weight of the objects to be weighed on the mounting table when the total weight of the objects to be weighed on the mounting table is significantly outside the appropriate range of the objects to be weighed. By checking, the object to be weighed can be added or taken out quickly. However, for the purpose of suppressing the flickering of the weight display, if the noise attenuation effect of the weight signal is uniformly increased regardless of the weight of the object to be weighed, the total weight of the objects to be weighed on the mounting table will be within the appropriate range of the object to be weighed. In a stage far from the above, the response speed of the weight display becomes slow, and eventually the identification of the approximate weight of the object to be weighed by the operator is delayed, so that the efficiency of the weighing work is lowered.

  Therefore, the measuring instrument according to the first aspect of the present invention follows the increase or decrease of the weight of the weighing object on the loading part and the weighing object on the loading part. A display unit in which a deviation from a predetermined weight value is sequentially displayed, and a controller that outputs a weight display value or a deviation display value on the display unit, and the controller is an object to be weighed on the mounting unit. The amount of change from the weight of the object to be weighed placed on the placing part before the start of the weighing operation is outside the predetermined weight range (however, the weight of the measuring instrument before the start of the weighing operation) In the case of (except the weight range corresponding to the vicinity of), the response speed of the weight display or the deviation display that changes following the increase / decrease in the weight of the object to be measured is made faster than in the predetermined weight range.

  According to such a configuration, it is possible to improve the efficiency of the weighing work in which the operator manually performs the quantitative packing of the objects to be weighed while visually checking the display on the display unit.

  For example, when the weight of the object to be weighed is far from the appropriate range, the noise attenuation effect of the weight signal in the filter processing is relatively weakened, but the response speed of the filter is increased, so that the weight display or deviation display described above is performed. The response speed can be increased, and consequently the efficiency of the operator's weighing work can be improved. When the weight of an object to be weighed approaches the appropriate range, the filter response speed is slowed by relatively increasing the noise attenuation effect of the weight signal, but the above flickering of weight display or deviation display is suppressed. it can.

  Further, the measuring instrument according to the second aspect of the present invention is the measuring instrument according to the first aspect, wherein a predetermined amount is set for each of a lower limit value and an upper limit value of an appropriate amount range of the object to be weighed or a target weight of the object to be weighed. Means are provided for setting the weight range.

  Further, the weighing instrument according to the third aspect of the present invention is the weighing instrument according to the first or second aspect, in which the controller does not change the weight display value or the weight display value or the deviation display response speed. Means are provided for maintaining the continuity of the deviation display value.

  Further, the measuring instrument according to the fourth aspect of the present invention is the measuring instrument according to any one of the first to third aspects, wherein the controller is predetermined in the vicinity of the weight of the measuring instrument before the start of the weighing operation. The response speed of weight display or deviation display is made slower than when the weight is out of the range.

  According to such a configuration, for example, in the vicinity of the zero point of the weighing instrument in the additive weighing method, flickering of the weight display can be suppressed by relatively increasing the noise attenuation effect of the weight signal. Therefore, the operator can easily determine whether or not zero calibration is necessary.

  Hereinafter, specific examples of the present embodiment will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals throughout all the drawings, and redundant description thereof is omitted. Moreover, this embodiment is not limited to the following specific examples.

[Device configuration]
Drawing 1 is a figure showing an example of a measuring instrument of an embodiment. FIG. 1 shows an automatic digital pan scale 10 that is an example of a weighing instrument 10. In the digital upper pan automatic balance 10, an upper limit value and a lower limit value of the weight of an object to be weighed are set, and the weight range of the object to be weighed between them is set as an appropriate amount range (for example, a pack of objects to be weighed (for example, a pack) Stuffing) is performed.

  As shown in FIG. 1, the digital upper plate automatic balance 10 includes a weighing unit 11, a main body 15, and a controller 20.

  The weighing unit 11 includes a weighing pan 12 (mounting unit) on which an object to be weighed is placed, and a weight sensor 13 such as a load cell that supports the weighing pan 12 and can weigh the object to be weighed on the weighing pan 12. . The weight sensor 13 of the weighing unit 11 is connected to the controller 20 via a known signal processing circuit (for example, an amplifier or an A / D converter) (not shown). Thereby, the weight of the object to be weighed on the weighing pan 12 is sequentially weighed by the weight sensor 13 and input to the controller 20.

  An operation unit 16 and a display unit 17 are disposed on the front surface of the main body 15. The operation unit 16 functions as means for inputting operations such as operation start and operation stop of the digital upper plate automatic balance 10 and various operation conditions of the digital upper plate automatic balance 10 to the controller 20. That is, by using the operation unit 16, various input signals by the operator's operation are input to the controller 20 and stored in the storage unit of the controller 20. For example, in the present embodiment, the operation unit 16 has a predetermined weight range of the approximate weight of the object to be measured (details) for each lower limit value and upper limit value of the appropriate amount range of the object to be measured, or for each target weight of the object to be measured. Functions as a means for setting (described later).

  The display unit 17 functions as means for indicating the weight of the object to be weighed, the state of the scale, a stable lamp for displaying weight, a determination lamp, and the like (details will be described later).

  The controller 20 is stored in the housing of the main body 15, performs a filter process of the weight signal of the weight sensor 13, and guides the weight of the object to be measured based on the weight signal after the filter process. As this filter processing, for example, moving average calculation of sampling data of a weight signal can be exemplified. Since the moving average calculation is well known, detailed description is omitted.

  Further, the controller 20 outputs a weight display value to the display unit 17, acquires the approximate weight of the object to be measured based on the weight signal before the filter process, and determines the noise attenuation effect of the weight signal in the filter process. The factor to be set is set based on this approximate weight. Thereby, the response speed of the weight display of the display part 17 can be changed.

  As a factor for determining the noise attenuation effect, for example, the number of sampling data for moving average calculation can be exemplified. That is, if the number of sampling data is increased, the noise attenuation effect of the weight signal in the moving average calculation becomes stronger. Then, the response speed of the weight display becomes slow, but the flicker of the weight display hardly occurs. If the number of sampling data is small, the noise attenuation effect of the weight signal in the moving average calculation is weakened. Then, flickering of the weight display is likely to occur, but the response speed of the weight display is increased.

  Here, if the number of sampling data for filter processing for moving average calculation is simply changed for a certain weight of the object to be weighed, the continuity of the filter output value (weight display value) is lost, and the number of sampling data is changed. The weight display value fluctuates due to. For example, in order to obtain the average value of sampling data with different numbers, if a shift register with different number of cell memories is prepared and the weight average value is switched according to the contents of the shift register at a certain weight of the object to be weighed, the weight display value Loss of continuity.

  Therefore, in the present embodiment, the controller 20 includes means for maintaining the continuity of the weight display value even when the response speed of the weight display of the display unit 17 is changed. For example, even when switching from a case where the number of sampling data is small to a case where the number is large, the continuity of the weight display value can be maintained by the following method.

  As an example, when a shift register for a moving average calculation filter with the number of sampling data “5” is provided, the weight display value is obtained by averaging the weight values stored in the five cell memories of the shift register. Consider a case where the weight display value falls within a predetermined weight range and a moving average calculation filter with the number of sampling data “10” is applied. In this case, in the shift register for the moving average calculation filter with the number of sampling data “10”, each of the above five data is moved into each of the five cell memories on the side where new data is stored. In each of the five cell memories into which old data is stored, the average value of the above five data is stored. And if these are made into the initial value, the continuity of the weight display value can be maintained. In other words, when the number of sampling data is changed, the initial value of the filter processing for the moving average calculation after the change is changed to prevent the filter output value (weight display value) from changing. It is better to match the value derived in the average calculation process.

  In the above, the moving average filter has been described as an example of the filter. However, for example, a cyclic low-pass filter may be used. In this case, the time constant can be changed to change the attenuation characteristics and response speed, but the continuity of the weight display value is maintained by maintaining the continuity of the output value of the filter. The initial value of the filter after switching is matched with the output value of the filter before switching the time constant.

  As described above, the digital upper pan automatic balance 10 according to the present embodiment can improve the efficiency of the weighing operation in which the operator manually performs quantitative packing of the objects to be weighed while visually checking the weight display. That is, in the present embodiment, the controller 20 determines the predetermined weight when the approximate weight of the object to be weighed on the weighing pan 12 is outside the predetermined weight range (excluding the weight range corresponding to the vicinity of the zero point). The response speed of the above weight display that changes following the increase / decrease in the weight of the object to be weighed is made faster than that in the range. For example, when the weight of the object to be weighed is far from the appropriate amount range, the response speed of the weight display can be increased by relatively weakening the noise attenuation effect of the weight signal in the filter processing. Further, when the weight of the object to be weighed approaches the appropriate range, flickering of the weight display can be suppressed by relatively increasing the noise attenuation effect of the weight signal. In addition, as a weight range corresponding to the zero point vicinity, the weight range below the minimum measurement amount of the digital upper plate automatic balance 10 can be illustrated as mentioned later, for example.

  The controller 20 may have any configuration as long as it has a control function. For example, the controller 20 includes a calculation unit and a storage unit. As a calculating part, MPU and CPU can be illustrated, for example. An example of the storage unit is a memory. The controller 20 may be composed of a single controller that performs centralized control, or may be composed of a plurality of controllers that perform distributed control in cooperation with each other.

[Operation]
FIG. 2 is a flowchart illustrating an example of the operation of the measuring instrument according to the embodiment. Drawing 3 is a figure showing an example of a display by a measuring instrument of an embodiment. The following operations are performed by the control program of the controller 20. Here, the following operation will be described by taking a digital scale having a weighing capacity of 3000 g, a scale weight of 1 g, and a minimum measurement amount of 20 g as an example. Further, in the quantitative packing (for example, packing) of the objects to be weighed by the digital upper pan automatic balance 10, the lower limit value (WD) and upper limit value (WU) and the stable permissible ratio (SR) of the weight of the object to be weighed are set. Can be set. Therefore, in the present embodiment, the following operation will be described assuming that WD = 300 g, WU = 320 g, and SR = 10%.

  First, when power is turned on to the digital pan automatic balance 10, WDnear (= WD−WD × SR = 270 g) and WUnear (= WU + WU × SR≈350 g) are calculated in step S1. That is, in the present embodiment, the threshold (WDnear, WUnear) of the predetermined weight range of the approximate weight (Wp) of the object to be weighed is used as the reference and the lower limit value (WD) and the upper limit value (WU) of the appropriate amount range of the object to be weighed. Is set. And the factor which determines the noise attenuation effect of the weight signal in a filter process is changed with this threshold value (WDnear, WUnear) as follows.

  When the object to be weighed is placed on the weighing pan 12 of the digital upper pan automatic balance 10, the controller 20 acquires the approximate weight (Wp) of the object to be weighed based on the weight signal before the filter processing (step S2).

  Then, it is determined whether or not the approximate weight (Wp) of the object to be weighed is larger than the minimum measurement amount (20 g) (step S3).

  Here, when the approximate weight (Wp) of the object to be weighed is not more than the minimum measurement amount (20 g), the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong (step S7), and the process proceeds to step S8. move on. For example, when the filtering process is a moving average calculation of sampling data of a weight signal, the number of sampling data for the moving average calculation is increased. That is, the controller 20 changes in accordance with the increase / decrease in the weight of the object to be weighed near the zero point of the automatic digital pan balance 10 as compared with the case where the approximate weight (Wp) of the object to be weighed is outside the predetermined weight range. The response speed of the weight display on the display unit 17 is reduced by reducing the response speed of the filter. Thereby, near the zero point of the digital upper pan automatic balance 10, flickering of weight display can be suppressed by relatively strengthening the noise attenuation effect of the weight signal. Therefore, the operator can easily determine whether or not zero calibration is necessary.

  On the other hand, if the approximate weight (Wp) of the object to be weighed is larger than the minimum measured amount (20 g), the process proceeds to the next determination step, and is the approximate weight (Wp) of the object to be weighed larger than WDnear (270 g)? It is determined whether or not (step S4).

  Here, when the approximate weight (Wp) of the object to be weighed is WDnear (270 g) or less, the noise attenuation effect of the weight signal in the filter processing is set to be relatively weak (step S6), and the process proceeds to step S8. For example, when the filtering process is a moving average calculation of sampling data of a weight signal, the number of sampling data for the moving average calculation is reduced. Thereby, when the approximate weight (Wp) of the object to be weighed is sufficiently small from the appropriate amount range (300 g-320 g), the response speed of the weight display can be increased by relatively weakening the noise attenuation effect of the weight signal.

  On the other hand, when the approximate weight (Wp) of the object to be weighed is larger than WDnear (270 g), the process proceeds to the next determination step, and whether or not the approximate weight (Wp) of the object to be weighed is larger than WUnear (350 g). Is determined (step S5).

  Here, when the approximate weight (Wp) of the object to be weighed is larger than WUnear (350 g), the noise attenuation effect of the weight signal in the filter processing is set to be relatively weak (step S6), and the process proceeds to step S8. . For example, when the filtering process is a moving average calculation of sampling data of a weight signal, the number of sampling data for the moving average calculation is reduced. Thereby, when the approximate weight (Wp) of the object to be weighed is sufficiently large from the appropriate amount range (300 g-320 g), the response speed of the weight display can be increased by relatively weakening the noise attenuation effect of the weight signal.

  On the other hand, when the approximate weight (Wp) of the object to be weighed is WUnear (350 g) or less, the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong (step S7), and the process proceeds to step S8. For example, when the filtering process is a moving average calculation of sampling data of a weight signal, the number of sampling data for the moving average calculation is increased. As a result, when the approximate weight (Wp) of the object to be weighed is within the appropriate amount range (300 g-320 g) or approaches the appropriate amount range, the response speed of the filter is slowed and the noise attenuation effect of the weight signal is relatively strong. By doing so, flickering of weight display can be suppressed.

  Next, the controller 20 performs a filter process on the weight signal of the weight sensor 13, and derives the weight (W) of the object to be measured based on the weight signal after the filter process (step S8).

  And it is determined whether the weight (W) of a to-be-measured object is larger than the minimum measurement amount (20g) (step S9).

  Here, when the weight (W) of the object to be weighed is equal to or less than the minimum measurement amount (20 g), as shown by reference numeral 100 in FIG. 3, the zero point display is shown and the determination lamp is turned off (step S15). At this time, since the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong, flickering of the weight display hardly occurs.

  On the other hand, when the weight (W) of the object to be weighed is larger than the minimum measurement amount (20 g), the process proceeds to the next determination step, and whether or not the weight (W) of the object to be weighed is larger than WD (300 g). Is determined (step S10).

  Here, when the weight (W) of the object to be weighed is WD (300 g) or less, as shown by reference numerals 101 and 102 in FIG. 3, the determination lamp lights in red (sign for determining the lightness of the object to be weighed) ( Step S14). At this time, if the approximate weight (Wp) of the object to be weighed is WDnear (270 g) or less, the noise attenuation effect of the weight signal in the filter processing is set to be relatively weak as shown by reference numeral 101 in FIG. Therefore, the response speed of the weight display becomes faster. If the approximate weight (Wp) of the object to be weighed is greater than WDnear (270 g), the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong as indicated by reference numeral 102 in FIG. As a result, the display stabilization lamp is lit and flickering of the weight display is unlikely to occur.

  On the other hand, when the weight (W) of the object to be weighed is larger than WD (300 g), the process proceeds to the next determination step, and it is determined whether or not the weight (W) of the object to be weighed is larger than WU (320 g). (Step S11).

  Here, when the weight (W) of the object to be weighed is larger than WU (320 g), as shown by reference numerals 104 and 105 of FIG. (Step S12). At this time, if the approximate weight (Wp) of the object to be weighed is larger than WUnear (350 g), as shown by reference numeral 105 in FIG. Since the setting is weak, the response speed of the weight display becomes faster. If the approximate weight (Wp) of the object to be weighed is not more than WUnear (350 g), the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong as shown by reference numeral 104 in FIG. Therefore, the display stabilization lamp is lit and flickering of the weight display is unlikely to occur.

  On the other hand, when the weight (W) of the object to be weighed is equal to or less than WU (320 g), the determination lamp is lit in blue (sign for determining the appropriate amount of the object to be weighed) as indicated by reference numeral 103 in FIG. 3 (step S13). . At this time, since the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong, the display stabilization lamp is turned on, and flickering of the weight display is unlikely to occur.

  In addition, the weight of said to-be-measured object is an illustration, Comprising: It is not limited to this example.

(Modification 1)
In the above embodiment, the digital upper plate automatic balance 10 is exemplified as the weighing instrument 10, but is not limited thereto.

  Drawing 4 is a figure showing an example of a measuring instrument of modification 1 of an embodiment. FIG. 4 shows a digital platform scale 30 which is an example of the present measuring instrument 30. In the digital platform 30, the upper limit value and the lower limit value of the weight of the object to be weighed are set, and the weight range of the object to be weighed between them is set as an appropriate amount range, and the quantitative weighing (for example, packing) of the object to be weighed is performed. Done.

  As shown in FIG. 4, the digital platform scale 30 includes a weighing unit 31, an operation display unit 35, and a controller 40.

  The weighing unit 31 includes a weighing table 32 (mounting unit) on which an object to be weighed is placed, and a weight sensor 33 such as a load cell that supports the weighing table 32 and can measure the weight of the object to be weighed on the weighing table 32. . The weight sensor 33 of the weighing unit 31 is connected to the controller 40 via a well-known signal processing circuit (not shown) (for example, an amplifier or an A / D converter). As a result, the weight of the object to be weighed on the weighing platform 32 is sequentially weighed by the weight sensor 33 and input to the controller 40.

  The operation display unit 35 includes an operation unit 36 and a display unit 37. The operation unit 36 functions as means for inputting operations such as operation start and operation stop of the digital platform balance 30 and various operation conditions of the digital platform balance 30 to the controller 40. That is, by using the operation unit 36, various input signals by the operator's operation are input to the controller 40 and stored in the storage unit of the controller 40. For example, in this modification, the operation unit 36 sets a predetermined weight range of the approximate weight of the object to be weighed for each lower limit value and upper limit value of the appropriate amount range of the object to be weighed or for each target weight of the object to be weighed. It functions as a means to do.

  The display unit 37 functions as means for indicating the weight of the object to be weighed, the state of the scale, a stable lamp for displaying the weight, a determination lamp, and the like.

  The controller 40 is stored in the housing of the operation display unit 35, performs the weight signal filtering process of the weight sensor 33, and guides the weight of the object to be weighed based on the weight signal after the filtering process.

  The control function of the controller 40 and the display function of the display unit 37 are the same as the control function of the controller 20 and the display function of the display unit 17 of the embodiment, respectively, and detailed description thereof is omitted.

(Modification 2)
In the above embodiment, the threshold (WDnear, WUnear) of the predetermined weight range of the approximate weight (Wp) of the object to be weighed is based on the lower limit value (WD) and upper limit value (WU) of the appropriate amount range of the object to be weighed. However, it is not limited to this. For example, even if a threshold value of a predetermined weight range of the approximate weight of the object to be weighed is set based on the target weight of the object to be weighed, and a factor that determines the noise attenuation effect of the weight signal in the filter processing is changed by this threshold value. I do not care. In the above-described embodiment, the example in which the stable permissible ratio (SR) is set is described. However, the stable permissible weight (gram) may be set.

(Modification 3)
In the above-described embodiment, the quantitative filling operation is to place the object to be weighed on the weighing pan from the state in which there is no object to be weighed on the weighing pan 12 of the digital upper plate automatic balance 10 until a predetermined weight value is reached. Although the example which employ | adopted what is called an addition measurement system was described, it is not restricted to this. The present technology can also be applied to a so-called subtractive weighing method in which a large number of objects to be weighed are first placed on a weighing pan and a predetermined amount of objects to be weighed are removed therefrom.

  For example, first, assuming that 1075 g of an object to be weighed is placed on the weighing pan, when a weighing operation for removing an object to be weighed by a predetermined weight of 100 g is performed, 975 g becomes the predetermined target weight due to the weight reduction.

  Until the weight of the object to be weighed is close to 975 g, the weight is displayed with a quick response so that the removal operation can proceed quickly, and the filter is made to have a slow response at around the first 1075 g and around 975 g. In addition to displaying the weight with a slow response, the damping characteristic of the vibration signal is sufficiently increased so that the predetermined weight of 100 g can be stored as 975 g which is a stable target weight value after the weight reduction.

  In this method, the weight value of the object to be weighed on the weighing pan may be directly displayed on the display unit. However, the deviation from the predetermined weight value of the object to be removed is displayed on the display unit. When the value is near the predetermined weight value or near 0, the filter is made to have a slow response, the vibration signal attenuation characteristics are enhanced, and the deviation is displayed with the slow response so that the operator can read the stable deviation. May be. In other ranges, the filter response is made faster so that the deviation is displayed with a quick response, so that the operator can efficiently remove the object to be weighed toward a predetermined amount. Also good.

  Even in the addition weighing method, the deviation of the weight value of the object on the weighing pan from the predetermined weight value may be displayed on the display unit. Also in this case, when the deviation is close to 0, it is preferable to make the filter have a slow response and enhance the attenuation characteristics of the vibration signal so that the deviation is displayed with a slow response.

(Modification 4)
In the above embodiment, the number of sampling data for the moving average calculation is exemplified as a factor for determining the noise attenuation effect of the weight signal in the filter processing. However, the present invention is not limited to this. For example, the factor of determining the noise attenuation effect of the weight signal in the filter processing may be the number of moving averages when a plurality of moving averages are taken for sampling data.

(Modification 5)
In the above embodiment, when the approximate weight (Wp) of the object to be weighed is not more than the minimum measured amount (20 g) in Step S3, and when the approximate weight (Wp) of the object to be weighed is WUnear (350g) or less in Step S5. However, the flow proceeds to step S7, and the flow is such that the noise attenuation effect of the weight signal in the filter processing is set to be relatively strong. For example, the noise attenuation effect of the weight signal may be increased or decreased between the two.

  One embodiment of the present invention can improve the efficiency of weighing work in which an operator manually performs quantitative packing of objects to be weighed while visually checking the display on the display unit. Therefore, one embodiment of the present invention can be used, for example, in a measuring instrument for quantitatively filling an object to be weighed.

10 Weighing machine (digital pan automatic weighing machine)
DESCRIPTION OF SYMBOLS 11 Weighing part 12 Weighing pan 13 Weight sensor 15 Main body 16 Operation part 17 Display part 20 Controller

Claims (7)

The weight of the object to be weighed or the deviation from the predetermined weight value is sequentially displayed following the increase / decrease in the weight of the object to be weighed on the placing part and the weight of the object to be weighed on the placing part. And a weight sensor for weighing the object to be weighed on the placement unit, and the weight signal of the weight sensor is filtered to perform the filter processing based on the weight signal after the filtering process. guides the weight of weighed, a controller for outputting a weight display or deviation display value on the display unit, a measuring instrument Ru provided with,
The controller determines that the amount of change in the approximate weight of the object to be weighed on the placement unit from the weight of the object to be weighed placed on the placement unit before the start of the weighing operation is When the weight is outside the predetermined weight range excluding the weight range corresponding to the vicinity of the weight of the weighing instrument at the point of time, the increase / decrease of the weight of the object to be weighed is followed as compared with the case within the predetermined weight range. A measuring device for setting a factor for determining a noise attenuation effect of the weight signal in the filter processing so that a response speed of a weight display or a deviation display that changes with time is increased . 2. The measuring instrument according to claim 1, wherein the filtering process is a moving average calculation of sampling data of the weight signal, and a factor that determines a noise attenuation effect of the weight signal is the number of the sampling data. The measuring device according to claim 1, wherein the filter processing is low-pass filter processing of the weight signal, and a factor that determines a noise attenuation effect of the weight signal is a time constant of the low-pass filter. Wherein each lower limit and upper limit of an appropriate amount range of the objects to be weighed, or the each target weight of the objects to be weighed, according to any of claims 1 -3 comprising means for setting said predetermined weight range Scales. Wherein the controller, even if you change the response speed of the weight display or the deviation display, in any one of claims 1 -4 comprising means for maintaining the continuity of the weight display value or the deviation display value The measuring instrument described. The controller may change the initial value of the filter processing after the change so that the continuity of the weight display value or the deviation display value is maintained even when the response speed of the weight display or the deviation display is changed. The measuring device according to any one of claims 1 to 4, wherein the weighing device is made to coincide with a derived value of the filtering process. The controller slows down the response speed of the weight display or the deviation display in the vicinity of the weight of the measuring instrument before the start of the weighing operation, as compared with a case outside the predetermined weight range. 7. The measuring instrument according to any one of 6 .

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