DD281661A5 - CIRCUIT ARRANGEMENT FOR DETECTING TURNING POINTS OF ANY POSSIBLE MEASUREMENT RATE - Google Patents

Abstract

The invention relates to a circuit arrangement for detecting inflection points of arbitrary Meszwertverlaeufe with temporal assignment of the same, especially in fast veraenderlichen processes in which analog electrical signals are pending. A sample and hold 1 are followed by an A / D converter 2 which is connected directly and via a shift register 3 to a subtractor 4, which in turn is coupled to a comparator 6 directly to a comparator 6 via a second shift register 5 Data output is connected to the clock input of a latch 8. Connected to the data input of the latch 8 is the data output of a counter 7 which, like the sample and hold and the shift registers, is coupled to a clock generator 9. At the data output of the catch register is the time of the inflection point. FIG {inflection point; Meszwertverlauf; Assignment, temporally; Sample and hold; A / D converter; subtractor; Shift register; comparator; Counter; Latch}

Description

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Title of the invention

Circuit arrangement for detecting inflection points of arbitrary measured value profiles

Fields of application of the invention

IULe invention relates to a circuit arrangement for temporally associated detection of inflection points of any Meßvertverläufe in the presence of electrical measurement signals, especially in the evaluation of indicator diagrams of Kolbendampfmasohinen ·

Characteristic of the known state of the art

Disadvantages are that a computer is required, high costs and a low processing speed. Last disadvantage makes the application impossible especially for fast-running processes The location of the turning points is also recognizable only after expiry of the seeded puncture * Furthermore, the use of analog differentiating circuits is known (eg B. Kuehne 1, C ": linear and non-linear analog circuits with operational amplifiers, military publishing house of the GDR, 1st edition 1982, DE-PS 220 363 6), analog differentiators are inaccurate and leave no temporal Assignment of turning points to «

Object of the invention

The aim of the invention is to provide a circuit arrangement with which, with reduced component expenditure, increased evaluation speed and high accuracy and reliability, inflection points can be determined in the case of measured value curves.

Explanation of the essence of invention

The invention is based on the teohnisohe object to develop a circuit arrangement with the inflection of rapidly varying analog signals inflection points can be determined and selected with temporal assignment ·

According to the invention the object is achieved in that a sample and hold an analog-to-digital converter is connected, the data output is connected on the one hand directly to a subtractor, on the other hand via a shift register with the second data input dioses subtractor · The data output of the subtractor is again to one directly to the other via a second shift register, coupled to a comparator · The data output of the! Comparator is connected to the clock input of a latch whose data input is connected to the data output of a counter · The clock inputs of the Sample and Hold, the two shift registers and the counter are connected to a clock generator.

The sound signal, which is pending as an analogue electrical signal, arrives at the input of the sample and hold and is clocked via the clock input with the clock coming from the clock · over the output of the sample, and hold reaches the «malog clocked signal to the input of the fnalog -Digltal converter, which provides a binary word at its data output, which corresponds to the value which is applied to the input of the A / D converter, · This binary word is applied to the data input of the shift register, which is also clocked, so that at the data output At the second data input of the subtract, the instantaneous signal coming from the A / D converter is present and is subtracted from the information present at the data output of the shift register Difference at the data output of the subtractor provided · This information is used with the following n Shift register again delayed by one clock * The information applied to the data output of the shift register is transferred to the data output of the subtractor

applied information by means of the! Comparator compared. The clock coming from the clock generator is counted with the counter so that the current counter reading is available at its data output. If a turning point has been reached, this time value is stored in the latch by the pulse appearing at the data output of the collimator. Thus, at the data output of the on-aggregate, the time is available at which the inflection point appeared and can be processed further · The circuit arrangement is capable of recognizing and storing any inflection point with its time value *

Bs is also possible to detect the temporal assignment of extreme values and the type of extreme values when the data input of the second shift register is directly connected to the data output of the A / D converter · At the data output of the subtractor is the first derivative of the input signal

Ausfühvungsbejapiel

The invention will be explained in more detail below with reference to an ELgur which shows the circuit arrangement *

A sample and hold 1 are followed by an analog-to-digital converter 2, which is connected directly and via a shift register 3 to a subtractor 4, which in turn is coupled directly to a comparator 6 via a second shift register 5, whose data output DO is connected to the clock input C of a latch 8. The Datenausgaog a counter 7 is connected to the data input DI of the Auffangregist3rs. The clock inputs C of the sample and hold 1, the shift registers 3 and 5 and the counter 7 are coupled to a clock generator 9.

Hit each clock in Sample and Hold 1, the analog input signal I ^ scanned and stored. The signal appearing at the output 0 of the sample and hold is converted in the analog-to-digital converter 2 into a 10-bit-wide word. This digital information is delayed by the shift register 3 for the duration of one clock.

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The information present at the data output DO of the analog-to-digital converter 2 is subtracted from the information present at the data output DO of the shift register 3 with the aid of the subtractor 4 and the difference is provided to the data output of the subtractor 4 · This information is the second shift register 5 again Clock delayed · By means of the comparator 6, the information applied by the shift register 5 and the subtracter 4 is compared. The clock is counted with the counter 7 and is present as a time value at the data output DO of the counter 7. If a turning point is reached, this time value is stored in the latch θ by the pulse appearing at the data output from the comparator 8. At the data output DO of the latch θ is thus as the output signal 0, the time at which the inflection point rail is

Claims (1)

claim Circuit arrangement for detecting inflection points of arbitrary measured value profiles with time allocation thereof, characterized in that a sample and hold (1) an analog-to-digital converter (2) is nachgesohaltet whose data output (DO) on the one hand directly to a subtractor (4), on the other hand is connected to the subtractor (4) via a shift register (3) and the data output (DO) of the subtractor (4) is coupled directly to a comparator (6) via a second shift register (5) whose data output ( DO) is connected to the clock input (C) of a latch (θ) and the data input (D1) of the latch (θ) is connected to the data output (DO) of a counter (7), wherein the simple and hold (i), the Shift registers (3); (5) and the counter (7) a clock generator (9) is connected upstream 1 stu