JPS60112325A - Automatic correction signal processor - Google Patents

Abstract

PURPOSE:To omit a potentiometer for control of zero and span and also to attain an automatic correcting job by storing the corrected values of both the zero and span for each point of measurement and calculating the measured value sent from a detector with said corrected value to obtain the corrected measurement value. CONSTITUTION:The input signal of each point of measurement is first set at 0(mV) and applied through each of terminals 11, 12.... A central processor 6 drives S1, S2... of a switch 2 to digitize the data obtained during the input 0(mV) of each point of measurement by an A/D converter 3 to obtain data of alpha1, alpha2.... These data are stored in a memory 7. Then the input signal is set at the span value, and the correction values obtained when the span reference voltage Es(mV) is applied are stored in the memory 7 in the form of beta1 and beta2.... Thus the corrected value is obtained for both zer and span controls. The measurement values obtained by S1, S2... of the switch 2 are corrected by the zero and the span stored in the memory 7 for each point of measurement. Thus the corected measurement value is obtained and displayed on a display device 5 or delivered via an output part 8.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical field to which the invention pertains The present invention relates to a signal processing device, and in particular to an automatic signal processing device that digitizes a signal from a detector such as a thermocouple and processes this signal in accordance with the application. The present invention relates to a calibration type signal processing device.

(b) Prior Art Conventionally, multi-point input switching devices using relays or semiconductor FL (T switches) have been used in various measuring devices, but in particular low mV switching devices such as thermocouples require switching Due to the relationship between the leakage current of the "ON" resistor, the bias current of the amplifier connected to this, and the input impedance, there will be a slight difference between the input value and the value output from the switch. Since this problem also occurs at each measurement point, it has been impossible to perform common zero adjustment and span adjustment at each measurement point on the output side of the switching device.

Therefore, in the past, zero adjustment was performed for each measurement point.
Since it was necessary to install a potentiometer for span adjustment, as the number of measurement points increases, not only does it take a lot of time to adjust, but the circuitry is also complicated9, resulting in high costs.

(e) Object of the Invention The present invention has been made to solve these drawbacks, and therefore, an object of the present invention is to eliminate the adjustment mechanism such as a potentiometer, and to provide a relatively simple and inexpensive method. It is an object of the present invention to provide a new signal processing device of an automatic calibration type that can be configured, easily and automatically adjusted.

(d) Structure of the Invention In order to achieve the above object, the automatic calibration signal processing device according to the present invention comprises an A/D converter that receives a measurement value signal from a detector and converts the signal into a digital signal, and a setting device that commands an operation; a storage device that applies a reference voltage to an input terminal in advance, measures zero and span correction values of a measurement point according to commands from the setting device, and stores these correction values; 0 (e) Embodiments of the Invention Next, preferred embodiments of the present invention will be described. One embodiment will be specifically described with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. In the figure, measurement value signals are supplied from various detectors to the input terminals 11 and 12 and the concave curve 1n, respectively, and these input measurement value signals are sent to the nwitch 511S2 of the long switch 2.
, concave curve...incorporated by switching Sn,
The Φ converter 3 converts the signal into a digital signal. This digitized signal is input to the central processing unit 6 and subjected to calculations such as linearization, and then stored in the storage device 7.

This data is normally compared with the set value manually set by the setting device 4 with reference to the display 5, and the central processing unit 6 outputs the result as an adjustment signal or an alarm signal from the output section 8. Alternatively, it is used in various signal processing devices, such as displaying input and calculated data on the display 5 or outputting it to a printing device via the output unit 8.

In such a device, it is necessary to connect a reference human input signal to an input terminal during device manufacture or before use, and to adjust each measurement point to within a predetermined accuracy. In this device, this is performed by connecting a reference voltage generator to the input terminals 11, 12, . . . , and applying a human signal. Initially, the input signal of each measurement point is applied as Q (m'V), and the setting device 4 gives a command to collect the Q (mV) correction value to the central processing unit 6. [61-
t, the data at the time of input Q (mV) of each measurement point is converted into ~1000 by converter 3 by driving 81, S2, ......Sn of switch 2. Digitized α11α2, ・・・・・・・・・ α! It is stored in the storage device 7 as system data. When all point measurements are completed, the central processing unit 6 indicates on the display 5 that the zero point measurement is complete.

Next, set the human signal to the span value and span reference voltage Es
Similarly, the correction values when applying (mV) are β1, β2...
By storing it in the storage device 7 as βn, this signal processing device can obtain the zero adjustment and span shrine correction values, and the central processing device 6 can obtain the input value by performing the following calculation. The true value Et corresponding to is obtained.

An example of the operation flow of the present invention is shown in FIG. 2.

If the measured value obtained by the switch 81 of the switch 2 is shifted from El, the calibrated measured value (true value) Etx is obtained, collected at each measurement point in the same way, and stored in the storage device 7. By correcting with stored zero and span correction values,
Calibrated measurements can be obtained without using zero or span adjustment potentiometers.

As the storage device 7, if a non-volatile read/write memory is used that does not lose its stored contents even if the telephone number disappears, the telephone number,
When "OFF", this correction value is retained without being lost and can be used again. In addition, although the above embodiment was explained using a system equipped with a highly effective multi-point switching device, this calibration force method can also be applied to a single-point measurement force method that does not use a multi-point switching device. It is naturally effective because errors are also corrected.

In this embodiment, for convenience of explanation, it has been explained that each channel is calibrated at the same time, but it goes without saying that a specific channel can be specified and correction values can be collected only for that channel.

(f) As described in the detailed description of the invention, the present invention captures human input signals ~Φ
The converter converts the signal into a digital signal, the central processing unit calculates the signal, and the data is stored in the storage device.The zero and span standards are set in advance before inputting the measurement data from the detector. A signal characterized in that a voltage is input, zero and span correction values are stored for each measurement point, and a calibrated measurement value is obtained by calculating the measurement value from the detector using the correction value. Therefore, zero and span adjustment potentiometers are not required, and the calibration work is automated, resulting in great labor-saving effects and high reliability at low cost.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG.
The figure is a chart showing an example of the operational flow of the present invention. 11.12, in... e input terminal, 2... input switch 1.3... A/D converter, 4... setting device, 5...
・Display device, 6...Central processing unit, 7. Chugoku Registrar Patent Applicant Okura Electric Co., Ltd. Agent Patent Attorney Yutabe Kumagai" (C) To the Mountain 2. Recessed Procedural Amendments 1980 April 4th Director of the Japan Patent Office Kazuo Wakasugi Indication of the case 1982 Patent Application No. 220345 2 Name of the invention Automatic calibration signal processing device 3 Relationship with the Ministry case for amendment Patent applicant address Suginami, Tokyo Ward Narita Nishi 3-20-8 Name
Okura Electric Co., Ltd. Representative Representative Director Uki Okura 2016 Agent address - 1632 Shukugawara, Tama-ku, Yozaki City, Kanagawa Prefecture Dia Palace Noborito No. 2407 Detailed description of the invention column and drawing 4 Contents of amendment ■1 In formula (1) on page 5, line 20 of the specification of the present application, r(1+J
Correct "Yes" to "r(1-J"). 1. On page 6, line 7 of the same page, "non-volatile generation" is replaced with "recurrence".
I am corrected. 1. Correct Figure 2(b) as shown in the attached sheet. ρ's first run (entered Es territory V) (b) 2nd Kasumi

Claims (1)

[Claims] An A/D converter that takes in a measured value signal from a detector and converts the signal into a digital signal, a setting device that commands the operation of the device, and a reference voltage applied to the input terminal in advance to receive commands from the setting device. a storage device that measures zero and span correction values at measurement points and stores the correction values; and a storage device that stores the correction values at the measurement point, and performs calculations on the digital signal during measurement using the correction values stored in this storage device to obtain calibration data. An automatic calibration signal processing device characterized by comprising a central processing unit.