JP2009085592A - Electronic balance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic balance capable of automatically canceling sensitivity calibration during a measuring operation. <P>SOLUTION: The electronic balance which calibrates sensitivity at prescribed periods is provided with an infrared sensor 13 for sensing the presence of a gauger. An arithmetic and control part 3 checks whether the temperature detected by a temperature sensor 22 and a temperature change within every prescribed period of time have exceeded a specific range and a calibration period of time, checks whether the gauger has been sensed or not in the case that they have exceeded them, and transmits control signals in the case that the gauger has been sensed to halt the operations of a weight addition and removal mechanism 4 and reject sensitivity calibration. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic balance and an electronic balance, and more particularly to an electronic balance and an electronic balance having an automatic calibration function.

  In conventional electronic balances, the internal weight is generally sent to the load detector every time the internal temperature itself or the temperature change exceeds a specified value or the time for sensitivity calibration set in advance by the user is reached. An automatic sensitivity calibration function that corrects the measurement sensitivity by adding and subtracting is provided (see Patent Document 1).

JP-A-3-54420

For conventional electronic balances, if automatic sensitivity calibration of the electronic balance that is performed at a temperature change or time set by the user is set, the automatic sensitivity is required if no sample is placed on the weighing pan of the electronic balance even during weighing. Since the calibration is activated, there is a problem that it must be canceled by key operation.
The present invention has been made in view of such circumstances, and automatically cancels the automatic sensitivity calibration in the middle of the weighing operation without the user's key operation, eliminating unnecessary troublesome operations during the user's weighing operation. The purpose is to provide an electronic balance.

  In order to achieve the above object, the electronic balance of the present invention includes a built-in weight and a weight addition / deletion mechanism, and automatically calibrates sensitivity or sensitivity and linearity when a temperature change or a calibration time interval exceeds a certain value. In an electronic balance equipped with an automatic calibration function, the sensor for detecting the weighing person who operates the electronic balance and the automatic calibration cancellation that automatically cancels the automatic calibration while this sensor is sensing the weighing person It has a mechanism.

  The electronic balance of the present invention automatically cancels the automatic sensitivity calibration during the weighing operation, so the sensitivity calibration is not performed during the weighing operation. It is no longer necessary to interrupt the operation, and it is possible to perform a stable weighing operation while being free from unnecessary troublesome operations during the weighing operation.

  Embodiments of the electronic balance of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing an appearance of an electronic balance according to an embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the electronic balance. As shown in FIG. 1, the electronic balance has a tray 11 supported on a main body 1, a power switch 12 at the rear of the side, an infrared sensor 13 at the top of the front, and a display unit 17 for displaying a measured value at the front. A calibration key 14 for instructing calibration of measurement sensitivity performed by driving a built-in weight, which will be described later, a range key 15 and a unit key 16 for selecting a measurement range and unit of measurement values, etc. ing.

  As shown in FIG. 2, the main body 1 has a weight adding and removing mechanism 4 for loading a built-in weight 41, a load detecting unit 2 for detecting a load load of the object to be measured and the built-in weight 41, and a weight detection signal for weight measurement. A calculation control unit 3 for converting the value into a value and outputting the measurement value data to the display unit 17 is incorporated.

  The load detection unit 2 is loaded with an object to be weighed on the tray 11 or a built-in weight 41, a load detection mechanism 21 for detecting the load, a temperature sensor 22 for detecting the temperature inside the load detection unit 2, and a future sensor The switch 23 is configured to periodically switch the detection signal according to a control signal from the arithmetic control unit 3, and the A / D converter 24 converts the output signal into a digital signal.

  The arithmetic control unit 3 is mainly composed of a microcomputer, and includes a CPU 31 for performing arithmetic processing, an initial startup program for setting a measurement range and a measurement unit after power-on and sensitivity calibration, and a dish load. An arithmetic processing program for detecting and converting to a measured value and an arithmetic control program including a calibration determination program for taking in an output signal of the infrared sensor 13 and an output signal of the temperature sensor 22 and determining whether to perform sensitivity calibration are stored. A ROM 32, a RAM 33 for storing input data, calculation data, calculation parameters, and the like, and an input / output interface 34 for connecting various input / output devices to be described later to the calculation control unit 3.

  The input / output interface 34 includes a calibration key 14 for automatically operating the A / D converter 24, the temperature sensor 22, and the built-in weight 41 to perform sensitivity calibration, a range key 15 for selecting a measurement range, and a measurement. An operation key group such as a unit key 16 for selecting a unit, an infrared sensor 13 for detecting the presence of a measurer, and a display unit 17 for displaying a measured value are connected.

  The weighing operation of the electronic balance having the above configuration will be described with reference to the flowcharts of FIGS. When the power is turned on (S1), the predetermined measurement range and measurement unit are set by the initial setting program, and the zero point and the measurement sensitivity are calibrated by adding and removing the internal weight 41 by the sensitivity calibration program (S2). The weighing is executed (S3).

  Every time the weighing is performed (S3), it is checked whether the preset calibration interval time has reached the specified T time (S4), and the calibration interval time has not reached T time, and the load detection unit 2 is equal to or less than the specified value A (S5), or if the temperature Ta is B or more and C or less (S6), the measured value is displayed on the display unit 17 and the next measurement is performed (S3). .

  Further, when the calibration interval time reaches T time (S4), or when the temperature change ΔTa is larger than A (S5), or when the temperature Ta is lower than B and higher than C (S6), the infrared sensor 13 is measured. Is detected (S8), the sensitivity calibration is passed (S9), the measured value is displayed on the display unit 17 (S7), and the next measurement is performed (S3). On the other hand, when the infrared sensor 13 does not sense the weighing person (S8), sensitivity calibration is executed (S10), the measured value is displayed on the display unit 17, and the next weighing is performed (S3).

  In the above embodiment, sensitivity calibration is performed using one inner copper, but sensitivity and linearity calibration can be performed simultaneously by using two identical inner coppers. The present invention is not limited to the above-described embodiments, and various modifications can be considered. For example, although an infrared sensor is used to detect a measurer, a detection sensor using radio waves or ultrasonic waves may be used.

  The present invention is used for electronic balances and scales.

It is a perspective view which shows the external appearance of an electronic balance. It is a block diagram which shows the structure of the electronic balance by an Example. It is a flowchart figure explaining operation | movement of an electronic balance.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 11 Receptacle 12 Power switch 13 Infrared sensor 14 Calibration key 15 Range key 16 Unit key 17 Display part 2 Load detection part 21 Load detection mechanism 22 Temperature sensor 23 Switch 24 A / D converter 3 Calculation control part 31 CPU
32 ROM
33 RAM
34 Interface 4 Weight control mechanism 41 Built-in weight

Claims (1)

An electronic balance equipped with an internal weight and its weight addition / deletion mechanism, and with an automatic calibration function that automatically calibrates sensitivity or sensitivity and linearity when the temperature change or calibration time interval exceeds a certain value. An electronic balance comprising a sensor for sensing a weighing person to be operated and an automatic calibration canceling mechanism for automatically canceling automatic calibration while the weighing person senses the weighing person.

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