JP2001317991A - Electronic balance/weighing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electronic balance/weighing machine, capable of weighing after a suitable warm-up operation. SOLUTION: After power-on, a CPU2 reads the energizing time from a timer 3, reads the power-off time and temperature characteristic data of a load detector 5 from a memory 4, calculated the time required for warm-up operation, using a warm-up operation time calculating means 20, displays the lapsed time and the required time for the warm-up operation on a display 1, and reports that the weighing machine is in a weight display mode ready for weighing, after the warm-up operation ends.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic balance / scale which requires a warm-up operation for a predetermined time before use. In addition, the present invention relates to a so-called electronic balance such as a load cell type or a tuning fork type using a so-called electronic balance or strain gauge, such as an electromagnetic force balance type, or a so-called electronic balance such as a capacitance type, and furthermore, an electric weighing device by other methods The term electronic balance / scale also includes such electronic weighing devices.

[0002]

2. Description of the Related Art Electronic balances / scales take in digitally converted data of load data (output signals) from a load detecting section having a load sensor, and average the finite n data by a moving average or the like. To the sensitivity coefficient, or
It is configured to convert to a mass value by arithmetic processing such as multiplication by a span coefficient, determine a weighed value, and display the weighed value on a display.

In this type of electronic balance / scale, the load detector has a temperature drift (temperature dependency), and a temperature error (sensitivity error) of the load detector caused by a rise in temperature after the power is turned on. In general, a warm-up operation is performed for a predetermined time until a stable temperature state is obtained.

[0004]

However, conventional electronic balances / scales do not have a function for informing a user that a warm-up operation is being performed, and the measurer himself has been required to warm-up since the start of power-on. Driving hours had to be managed. Therefore, weighing (measurement) starts without sufficient warming-up operation being performed, that is, by the end of the warming-up operation in which the load detector reaches the temperature stable state, thereby causing a temperature drift. Is displayed on a display device as a display device or printed out by a printer.

[0005] However, from the displayed value,
A distinction is made between whether the measured value (measured value) is unreliable and inaccurate measured value data affected by temperature drift or reliable and accurate measured value data without the effect of temperature drift (determination). Because it is not possible, an incorrect measurement result affected by the temperature drift may be adopted as a correct measurement value. Further, the warm-up operation time may be extended so as not to be affected by the temperature drift. However, in this case, the warm-up operation is performed more than necessary, and the work efficiency until the end of the measurement is deteriorated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an electronic balance / scale capable of performing measurement after a proper warm-up operation.

[0007]

In order to solve the above-mentioned problems, an electronic balance / scale according to the present invention is provided with a function of notifying that a warm-up operation is being performed. , When the power was off, or
A warm-up operation time calculating means for calculating a time to perform a warm-up operation based on the temperature of the load detection unit at the time of power-on; and a warm-up operation being performed based on the time calculated by the warm-up operation time calculating means. It is realized by the notification means to notify whether or not

More specifically, a storage device storing information relating to the temperature characteristics of the load detector, and information stored in the storage device are read out when the power is turned on, and the power supply is cut off based on the information. A warm-up operation time calculating means for calculating a warm-up operation time required for the load detector to reach a temperature stable state in accordance with the power-off time, and a warm-up operation calculated by the warm-up operation time calculation means. Based on driving time,
And an informing means for informing whether or not the warm-up operation is being performed.

According to a first aspect of the present invention, a clock device for generating a signal indicating time is used to calculate a power-off time during which power has been cut off, and a signal from the clock device when the power is cut off. Power-off time storage processing means for storing a power-off time in the storage device, and a power-off time for calculating a power-off time from a signal from the clock device and a power-off time stored in the storage device when power is turned on. Time calculating means.

In this respect, an example of the information stored in the storage device is data indicating a relationship between a power-off time and a warm-up operation time, and the warm-up operation time calculating means uses the data based on the data. The warm-up operation time is calculated from the power-off time.

In this respect, another example of the information stored in the storage device includes first data indicating a relationship between a power-off time and a temperature of the load detection unit, and a temperature of the load detection unit. This is second data indicating a relationship with the warm-up operation time, wherein the warm-up operation time calculation means calculates the temperature of the load detection unit from the first data based on the power-off time, and calculates the temperature. The warm-up operation time is calculated from the second data based on the second data.

Further, from this viewpoint, still another example of the information stored in the storage device is a function for deriving a warm-up operation time using a power-off time as a variable, and the warm-up operation time calculation means uses the function. Is used to calculate the warm-up operation time from the power-off time.

According to a second aspect of the present invention, a storage device that stores information on temperature characteristics of a load detector, and information that is stored in the storage device when power is turned on is read out. A warm-up operation time calculation unit that calculates a warm-up operation time required for the load detection unit to reach a temperature stable state according to the temperature of the load detection unit when the power is turned on,
And a notifying unit for notifying whether or not a warm-up operation is being performed based on the warm-up operation time calculated by the warm-up operation time calculating unit.

In this respect, the load detecting section has a temperature sensor for detecting the temperature of the load detecting section.

In this aspect, the information stored in the storage device is data relating to a temperature characteristic indicating a relationship between the temperature of the load detector at power-on and the warm-up operation time. The calculating means calculates the warm-up operation time from the temperature of the load detection unit when the power is turned on based on the data.

In the present invention, it is preferable that the warm-up operation time calculating means sets a required maximum warm-up operation time when power is supplied for the first time. The display device for displaying the weighed value obtained by processing the load data from the detection unit can also be used.

The electronic balance / scale according to the present invention having such a configuration can measure the weight after proper warm-up operation, so that the inherent heat transfer characteristics of the mechanical parts and the electronic parts constituting the electronic balance / scale. The measurement error caused by the temperature drift due to the measurement can be eliminated. As a result, it is possible to prevent a measurement value during the warm-up operation or a measurement value having a temperature drift from being adopted as a correct measurement value.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the electronic balance / scale according to the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a schematic configuration of an embodiment of an electronic balance / scale according to the present invention, and FIG.
FIG. 2 is a block diagram functionally illustrating a (central processing unit).

Normally, the electronic balance / scale transmits the measurement data detected by the load detector 5 having a load sensor to the CPU 2.
Is converted into a weight value (mass value) by arithmetic processing such as multiplication by a sensitivity coefficient or a span coefficient, and the weighed value is displayed on the display device 1. The mechanical components and the electronic components constituting the load detection unit 5 have their own heat transfer characteristics, and due to a temperature change accompanying heat generation after energization, a measurement error due to a temperature drift occurs until the temperature becomes stable at a constant temperature. Therefore, in order to eliminate the measurement error, the electronic balance / scale needs a warm-up operation until the load detector 5 reaches a certain temperature.

In the first embodiment of the present invention, the warm-up operation time calculating means 20 realized by the CPU 2 calculates the warm-up operation time based on the power-off time. In order to calculate the power-off time, a clock device 3 and a storage device 4 that emit a signal indicating the time are provided. The CPU 2 stores a power-off time in the storage device 4 based on a signal from the clock device 3 when the power is turned off.
And a power-off time calculating means 24 for calculating a power-off time from a signal from the clock device 3 when the power is turned on and a power-off time stored in the storage device 4.

The display control means 26 displays the remaining time of the warm-up operation on the display device 1 during the warm-up operation based on the output from the warm-up operation time calculating means 20, and elapses the necessary warm-up operation time. If so, the display device 1 is controlled so that the weighed value obtained by processing the load data from the load detector 5 can be displayed.

When the power is turned on to the electronic balance / scale, time data is stored in the storage device 4 from the clock device 3 via the CPU 2 at regular intervals. The storage of the time by the storage device 4 is performed as needed until the power is turned off. When the power is turned off, the update of the time information is interrupted, and the time data lastly stored in the storage device 4 becomes the power-off time. . Further, the storage device 4 stores temperature characteristic data as information such as heat transfer characteristics of the load detection unit 5.

When the power is turned on again, the CPU 2
Read time data from. At that time, the power supply cutoff time and the temperature characteristic data of the load detector 5 are read from the storage device 4. Then, the CPU 2 calculates the time during which the power of the electronic balance / scale is shut off from the current energizing time and the power shut-off time of the previous use, and obtains a temperature stable state from the temperature characteristic data of the load detecting unit 5. Calculate the warm-up operation time required until it is completed.

The CPU 2 displays the required required warm-up operation time and the elapsed time of the warm-up operation on the display device 1, and the user determines whether or not weighing is possible based on the display contents of the display device 1. . When the required warm-up operation time elapses, CP
The display device 1 displays that the measurement is enabled by U2. When power is first supplied to the electronic balance / scale, since there is no previous power-off time information, the necessary maximum warm-up operation time is displayed, and the warm-up operation is performed based on this time.

FIGS. 3 and 4 show a flowchart of a series of processing operations according to the first embodiment of the present invention.
When the power is turned on, the time data is read from the clock device 3 even during the warm-up operation, and the elapsed time and the time required for the warm-up operation are displayed on the display device 1. Then, after the warm-up operation is completed, the weight is displayed to inform that the weighing is possible.

Specifically, the operation is first turned on and energized (S1). When the power is turned on for the first time, the warm-up operation time is set to the maximum (S6).
Processing is performed in S5 (S2). In S3 to S5, the CPU
Numeral 2 reads the energization time from the timepiece device 3, reads the power-off time at the last use and the temperature characteristic data of the load detector 5 from the storage device 4, and calculates and sets the time required for the warm-up operation. After the warm-up operation time is set, the time during the warm-up operation is measured, and the warm-up operation is performed while displaying information on the time (S7 to S10). When the warm-up operation time elapses, the weight can be measured (S9), and the interval timer starts (S11).

When the object to be measured is placed on the weighing pan of the load detector 5, the CPU 2 weighs (S12) and displays the weighed value (S1).
Perform 3), and if the interval time has not elapsed, ST1
2 (S14), after the elapse of the interval time (S14)
If so, the weighing value and the time are stored in the storage device (S15),
The interval timer is cleared (S16). When the weighing is continuously performed, the process proceeds to S11 (S1).
7) When the use is stopped, the power is cut off (S1).
8). The CPU 2 needs to read the time from the clock device 3 at regular time intervals in order to store the power cutoff time in the storage device 4. The interval timer is a counter for measuring an interval for reading the time.

If the suspension time (power interruption time) from the end time when the device was used immediately before to the power supply reactivation time is short, the time required for the warm-up operation is also small. Since the required warm-up operation time is calculated based on the power-off time from the end time when the device was used immediately before to the power-on time, appropriate warm-up operation and efficient measurement should be performed. Can be.

In order to realize the function of this embodiment, as an example of information on the temperature characteristics, the storage device 4 in FIGS. 1 and 2 stores the temperature characteristic data of the load detector shown in FIG. 5 and the data shown in FIG. Necessary warm-up operation time data is stored. The load detection unit 5 in FIGS. 1 and 2 generates heat with a constant calorific value during operation, converges to a certain temperature with the operation time, and becomes equilibrium at that temperature to stabilize the weighing value.

FIG. 5 shows the temperature characteristic of the load detector 5, which has been constant during operation, and decreases with time due to the power cutoff. The on-axis time Tn represents a time during which it can be considered that there is no temperature drop of the load detector, and the temperature of the load detector at that time is t1. The temperature characteristic data is obtained by calculating an approximate expression at the time of temperature adjustment, and is stored in the storage device 4. The temperature characteristic data indicating the relationship between the power-off time and the temperature of the load detector after the power-off stored in the storage device 4 in FIGS. 1 and 2 is not an approximate expression, but the characteristic diagram itself shown in FIG. It may be.

The load detector has a specific heat value,
FIG. 6 shows the relationship between the amount of generated heat as a parameter and the warm-up operation time required from the start of operation or the restart of operation to the equilibrium temperature. This characteristic diagram shows that the operation shut-off time is short, and the higher the temperature of the load detector 5 when the operation is resumed, the shorter the time required to reach the equilibrium temperature, that is, the shorter the required warm-up operation time. I have. The calorific value of the load detector can be grasped by an experiment, and FIGS.
Is stored in the storage device 4 shown in FIG. In addition, an approximate expression indicating the relationship with the warm-up operation time required from the start of the operation or the restart of the operation until the equilibrium temperature is reached is also obtained at the time of adjustment and stored in the storage device 4. The data indicating the relationship between the load detector temperature and the required warm-up operation time stored in the storage device 4 in FIGS. 1 and 2 is not an approximate expression but the characteristic diagram itself shown in FIG. Is also good.

The operation for obtaining the warm-up operation time using the data shown in FIGS. 5 and 6 is performed as follows. When the operation is started or when the operation is restarted, the CPU 2 reads the approximate expression shown in FIG. Next, the power-off time and the power-on time are read to determine the power-off time. As a result, the power cutoff time T0 is obtained, and the temperature t0 of the load detection unit is obtained from FIG. The data shown in FIG. 6 is read from the storage device 14, and the warm-up operation time is obtained from the obtained temperature t0 of the load detector. When the temperature of the load detection unit obtained from the power-off time is lower than t1, the warm-up operation time is obtained in this manner. In the embodiment, the temperature of the load detector is t
If it is higher than 1, the warm-up operation is not required.

FIGS. 7 and 8 show an example of the display screen of the display device 1. FIG. During the warm-up operation, as shown in FIG. 7, a symbol t indicating the warm-up operation and a display for clearly identifying that the display is not a weight display, for example, "STAND-B"
In addition to the display of "Y", a time display indicating the remaining warm-up operation time is performed. Of course, the display of symbols and characters is merely an example.
The PU 2 performs a weight display on the display device 1 as shown in FIG. 8 to notify that the measurement is possible. As an example of the weight display, unlike the warm-up operation display,
The display of “STAND-BY” disappears, and the symbols and characters indicating the warm-up operation time also disappear. Then the weight unit is displayed. Of course, this weight display is also an example.

In another embodiment of the present invention, the warm-up operation time calculating means 20 shown in FIG. 2 is based on the temperature of the load detector 5 at the time of power-on, and stores the power-on time stored in the storage device 4. The warm-up operation time is calculated from the data indicating the relationship between the temperature of the load detector 5 and the warm-up operation time. for that reason,
The load detecting section 5 includes a temperature sensor 6 for detecting a temperature, and the temperature sensor 6 constantly monitors the temperature of the load detecting section 5. The temperature sensor is usually provided near the load sensor of the load detection unit.

FIG. 9 is a flowchart showing the operation of this embodiment.
Shown in This chart corresponds to steps S1 to S6 in the flowchart of FIG. 3, and the operation after step S7 is the same as that shown in FIG. When the power is supplied (S1), the required maximum warm-up operation time is set for the first time (S6), but when the operation is restarted, the temperature is detected by the temperature sensor 6 (S3).
'), The data indicating the relationship between the temperature of the load detector 5 and the warm-up operation time when the power is turned on is read from the storage device 4 (S4).
'), A warm-up operation time is obtained from the data based on the detected temperature (S5).

FIG. 10 shows data stored in the storage device 4 in FIGS. 1 and 2 for realizing this embodiment. The relationship between the temperature of the load detector and the required warm-up operation time when the power is turned on. It is shown. Such a curve of the temperature characteristic is also obtained in the storage device 4 by obtaining an approximate expression at the time of temperature adjustment. The temperature at the time of turning on the power is measured by a temperature sensor 6 provided in the load detection unit 5. The calorific value of the load detector 5 can be grasped in an experimental stage of product development, and is also stored in the storage device 4.

The operations of steps S3 'and S4' in FIG. 9 are specifically performed as follows. When the power is turned on, the CPU 2 first reads the approximate expression of the characteristic curve in FIG.
Next, the temperature of the load detector 5 (the temperature at power-on) is measured. The warm-up operation time is obtained from the temperature. In the electronic balance / scale, the temperature sensor 6 is always provided in the load detection unit 5 in order to perform sensitivity calibration (correction) for a change in ambient temperature. Therefore, it is not necessary to separately provide a temperature sensor, and the warm-up operation time can be obtained by using the temperature sensor for sensitivity calibration.

In the embodiment, the storage device stores data or an approximate expression indicating information relating to the temperature characteristics of the load detecting section. Instead, the power supply cutoff time or the temperature of the load detecting section when the power is turned on is stored instead. May be stored as a variable to derive the warm-up operation time. In that case, CPU
Calculates the warm-up operation time from the power-off time or the temperature of the load detector when the power is turned on by using the function.

Further, in the embodiment, as a notification means, a display device for displaying a weighing (weight) value indicates that the weighing is enabled by displaying the weight, but a display for indicating that the weighing is enabled. Then, it is not limited to this. Further, in addition to visually appealing notification by the display of the embodiment, during warm-up operation by voice or buzzer, may be a notification to appeal to the auditory whether warm-up operation has been completed, in this case, The notification (warning) function provided in the CPU can be used.

[0040]

The electronic balance / scale according to the present invention is configured as described above, so that the weight can be measured after a proper warm-up operation, so that the mechanical parts and components constituting the electronic balance / scale can be measured. It is possible to eliminate a measurement error caused by a temperature drift due to a specific heat transfer characteristic of each electronic component. As a result, it is possible to prevent a weighing value during the warm-up operation or a weighing value having a temperature drift during the warm-up operation from being adopted as a correct weighing value.

[Brief description of the drawings]

FIG. 1 is a block diagram schematically showing one embodiment of an electronic balance / scale according to the present invention.

FIG. 2 is a block diagram functionally showing a CPU in the block diagram of FIG. 1;

FIG. 3 is a flowchart of a series of processing operations according to an embodiment of the present invention.

FIG. 4 is a flowchart of a series of processing operations according to an embodiment of the present invention.

FIG. 5 is a characteristic diagram illustrating a relationship between a power-off time and a temperature of a load detection unit after the power is turned off.

FIG. 6 is a characteristic diagram showing a relationship between a load detection unit temperature and a required warm-up operation time.

FIG. 7 is a diagram illustrating an example of a display state during a warm-up operation on the display surface of the display device.

FIG. 8 is a diagram illustrating an example of a state of weight display on a display surface of a display device.

FIG. 9 is a flowchart of a series of processing operations according to another embodiment of the present invention.

FIG. 10 is a characteristic diagram showing another example of the temperature characteristic data of the load detection unit, showing a relationship between the temperature of the load detection unit during energization and a necessary warm-up operation time.

[Explanation of symbols]

1: Display device 2: CPU 20: Warm-up operation time calculation means 22: Power-off time storage processing means 24: Power-off time calculation means 26: Display control means 3: Clock device 4: Storage device 5: Load detector 6: Temperature sensor

Claims (12)

[Claims] 1. An electronic balance / scale having a warm-up operation function for processing load data from a load detection unit to obtain a weighing value, wherein a function for informing whether or not a warm-up operation is provided is provided. Electronic balance / scale with special features. 2. The electronic balance / scale according to claim 1, wherein the function of notifying whether or not the warm-up operation is being performed is a time during which the power is turned off, or a temperature of the load detection unit when the power is turned on. A warm-up operation time calculating means for calculating a warm-up operation time required for the load detecting section to reach a temperature stable state based on the warm-up time. An electronic balance / scale, which is realized by a notifying means for notifying whether or not driving is being performed. 3. A storage device for storing information on temperature characteristics of a load detector, and information stored in the storage device when power is turned on, and power is cut off based on the information. A warm-up operation time calculation unit that calculates a warm-up operation time required for the load detection unit to reach the temperature stable state according to the time, and a warm-up operation time calculated by the warm-up operation time calculation unit. And an informing means for informing whether or not the warm-up operation is being performed. 4. The electronic balance / scale according to claim 3, wherein the power supply cutoff time is calculated based on a clock device that issues a signal representing a time, and based on a signal from the clock device when the power supply is cut off. Power-off time storage processing means for storing a power-off time in the storage means; and a power-off time for calculating a power-off time from a signal from the clock device and a power-off time stored in the storage device when power is turned on. An electronic balance / scale comprising a calculating means. 5. The electronic balance / scale according to claim 3, wherein the information stored in the storage device is data indicating a relationship between a power-off time and a warm-up operation time, and the warm-up operation is performed. The electronic balance / scale, wherein the time calculating means calculates the warm-up operation time from the power-off time based on the data. 6. The electronic balance / scale according to claim 3, wherein the information stored in the storage device is first data indicating a relationship between a power-off time and a temperature of the load detection unit;
And a second data indicating a relationship between the temperature of the load detector and the warm-up operation time, wherein the warm-up operation time calculator calculates the temperature of the load detector from the first data based on the power-off time. An electronic balance / scale for calculating a warm-up operation time from the second data based on the calculated temperature. 7. The electronic balance / scale according to claim 3, wherein the information stored in the storage device is a function for deriving a warm-up operation time using a power-off time as a variable.
The electronic balance / scale according to claim 1, wherein said warm-up operation time calculating means calculates the warm-up operation time from a power-off time using said function. 8. A storage device for storing information relating to temperature characteristics of a load detection unit, and information stored in the storage device when power is turned on. A warm-up operation time calculating unit that calculates a warm-up operation time required for the load detection unit to reach the temperature stable state according to the temperature, and a warm-up operation time calculated by the warm-up operation time calculation unit. And an informing means for informing whether or not the warm-up operation is being performed. 9. The electronic balance / scale according to claim 8, wherein a temperature sensor for detecting a temperature of the load detector is provided in the load detector. 10. The electronic balance / scale according to claim 8, wherein the information stored in the storage device is a temperature characteristic indicating a relationship between a temperature of the load detection unit at power-on and a warm-up operation time. Wherein the warm-up operation time calculating means calculates the warm-up operation time from the temperature of the load detection unit when the power is turned on based on the data. 11. The electronic balance / scale according to claim 3, wherein said warm-up operation time calculating means sets a required maximum warm-up operation time when power is supplied for the first time. An electronic balance / scale, characterized in that: 12. The electronic balance / scale according to claim 3, wherein the notifying means is a display device for displaying a weighing value obtained by processing data of the load detecting unit. An electronic balance / scale characterized by the following.