JPH0749992B2 - Electronic balance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an electronic balance. The present invention can be applied not only to a so-called electronic balance having an electromagnetic force balance mechanism or the like, but also to a so-called electronic balance having a load cell or the like as a load sensor.

<Prior Art> Generally, an electronic balance performs A-D conversion of a voltage value output according to a load value, performs temperature correction calculation and span calculation using this digital conversion data, and displays a weighing value to be displayed. The value is determined and digitally displayed. However, if the measured value is determined by one piece of data, the measured value will change momentarily due to disturbances and various other causes. The value is determined by the conversion.
The averaging number of the data, that is, the averaging time is automatically switched by a measurer by a dip switch or by using a digital filter in accordance with the degree of dispersion of the AD conversion data. There is one. Generally, the averaging time is set longer as the degree of data variation is larger to stabilize the display value.

<Problems to be solved by the invention> However, for a while immediately after placing the weighing object on the plate,
In a place where vibration is particularly large, the displayed value fluctuates even if an appropriate averaging time is set, and the fluctuation range is extremely difficult to read because it is a digital display. There was a problem that it was difficult to evaluate sex.

<Means for Solving Problems> The present invention has been made to solve the above problems, and its configuration will be described with reference to the basic conceptual diagram shown in FIG. The load detector b is determined by the determining means a.
In the balance that determines the measured value and digitally displays it on the display device c by averaging the load data sampled moment by moment using a predetermined plurality of pieces of information, information on the fluctuation range between the load data to be averaged is displayed. It is characterized by including the data variation information calculating means d to be obtained and the data variation information displaying means e for displaying information relating to the obtained variation range.

<Operation> In addition to displaying the measured value, information related to the fluctuation range between the load data used to determine the measured value will also be displayed, indicating how reliable the current measured value is. You can see at a glance what it is.

<Example> An example of the present invention will be described below with reference to the drawings.

FIG. 2 is a block diagram showing the system configuration of the embodiment of the present invention.

The load detection mechanism 1 generates a voltage signal corresponding to the load on the plate 1a, and this signal is digitized by the A / D converter 2 and taken into the arithmetic control unit 3 at a constant sampling cycle.

The arithmetic and control unit 3 is mainly composed of a microcomputer, and has a CPU 31, a ROM 32, a RAM 33, and an input port 34 for taking in data from the A / D converter 2 described above, and a weighing value W described later. And an output port 35 and an interface circuit 36 for outputting the calculation result of the standard deviation σ.

A driver 4a for driving the digital display 4 for displaying the weighing value W and a bar graph display 5 for displaying the standard deviation σ are provided to the arithmetic and control unit 3 via the interface circuit 36.
A driver 5a for driving the is connected.

The load data taken from the input port 34 is RA
The data is sequentially shifted and stored in the data storage area in M33. The ROM 32 performs the temperature correction calculation on the data in the RAM 33 based on the temperature information from the temperature sensor (not shown), and also converts it into the mass or weight value by multiplying the set span coefficient, etc. In addition to the known formula for calculating the measured value W that determines the measured value W by averaging a predetermined number of data, the formula for calculating the standard deviation σ between the data used for calculating the measured value W is written. There is. In this formula, for example, if the number of data used to obtain the metric value W is N, each data is di (i = 1 to N), and the average value of this data di is It is represented by. Then, each time the latest data is sampled, the weight value W and the standard deviation σ are calculated and displayed on the digital display 4 and the bar graph display 5, respectively.

FIG. 3 is an external view of the embodiment of the present invention described above, and FIG. 4 is an enlarged front view of the display panel portion P thereof. On the display panel P, adjacent to the digital display 4 for displaying the measured value W,
A bar graph display 5 for displaying the standard deviation σ is provided. This bar graph indicator 5 is a display element 5b such as an LED.
The display elements 5b ...
By turning on / off the light of 5b, the standard deviation σ can be displayed in an analog manner as a whole. That is, for example, if five display elements 5b are associated with one digit of the calculated standard deviation σ, the standard deviation σ can be displayed with a resolution of 0.2 digit by lighting one display element 5b.

With the configuration described above, when the measurement value W is read, the measurer can simultaneously know the information related to the fluctuation range of the load data used in obtaining the measurement value W.

Note that the information regarding the fluctuation range of the data is not limited to the standard deviation of the data, and the amount indicating the degree of other fluctuations,
Of course, it may be dispersed, for example.

<Effect of the Invention> As described above, according to the present invention, since the information related to the fluctuation range between the sampling data of the load used for the calculation of the measured value is calculated and displayed together with the measured value, It is possible to know at a glance how reliable the present measurement display value is.

In addition, by displaying the information related to the fluctuation range in a bar graph in an analog manner, the information can be sensuously read quickly, and even if the information itself related to the fluctuation range fluctuates a little. It is preferable because it can be read. Furthermore, the conventional electronic balance can be implemented by simply adding a plurality of display elements, their drivers, and some software, which is highly practicable and has a low cost burden for its implementation.

[Brief description of drawings]

 FIG. 1 is a basic conceptual diagram showing the constitution of the present invention, FIG. 2 is a block diagram showing the constitution of an embodiment of the present invention, FIG. 3 is its external view, and FIG. 4 is an enlarged front view of its display panel P. is there. 1 ... Load detection mechanism 1a ... Plate 2 ... A-D converter 3 ... Computational control unit 4 ... Digital display 5 ... Bar graph display 5b ... 5b ... Display element

Claims (2)

[Claims] 1. A balance for averaging load data sampled momentarily from a load detecting unit by using a predetermined plurality of data to determine a measured value and digitally displaying the same on a display, the load data to be averaged. An electronic balance comprising: a data variation information calculation means for obtaining information relating to a variation range between the two; and a data variation information display means for displaying the obtained information. 2. The electronic device according to claim 1, wherein the data variation information display means is an analog bar graph display in which a plurality of display elements are continuously arranged. Balance.