SU1174801A2 - Stroboscopic pressure indicator - Google Patents

Description

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Fig. 1 The invention relates to instrumentation J, in particular, to devices for recording periodic processes of piston machines. According to the main author. St. No. 618669 is known a stroboscopic pressure indicator, comprising a pressure sensor connected to an analog-to-digital converter, the output of which is connected to a digital indicator of a piston position sensor, a generator of recording start pulses, one input of which is connected to a trigger input of an analog-digital converter (ADC), and the other is with the first input of a digital meter of time intervals, the output of which is connected to the input of the digital accumulator by the CID of the known device are a small range AND is low accuracy of measurements. The purpose of the invention is to expand the range and increase the accuracy of the measurement of the ordinates of the periodic process, Ka Figure 1 shows a diagram of the stroboscopic pressure indicator; Fig. 2 is a sequence diagram for understanding the operation of the stroboscopic pressure indicator; FIG. 3 shows the control unit for the capacity of the ADC indicator of the indicator, the Stroboscopic pressure indicator contains a periodic sensor 1 installed on a piston machine, an ADC 3, a start-registration pulse generator, a digital storage device 5, a piston position sensor 6, a digital meter 7. time intervals and unit 8 for controlling the capacity of the ADC counter. A unit with a counter capacity T, T ..., T., an analog-to-digital converter ADC consists of a control unit (CU), a decoder (LH) and keys K., (,, K, K. 20, K. The stroboscopic pressure indicator works as follows: when registering a periodic process v from sensor 1 installed on a piston machine 2, the ordinates are converted into a digital code in ADC 3. The value of the capacity of the ADC counter is less than the order values of the process make cyclical overflows (turnovers), after which incomplete filling The ADC counter will register the remainder by module whose value is equal to the ADC counter capacitance, the residual value S is recorded in the digital accumulator Before each measurement of the periodic process ordinates the ADC capacitance value is set using the control unit 8. Each value of the ADC counter capacitance capacity module corresponds to its own cyclogram, built on the recorded residues in the digital storage device 5. The set of cyclograms in the system of residual classes restores the recorded periodic process to the positional oh system I- / I-h - g R 4- 1 1 / (where y is the magnitude of the ordinates in the positional system; - modular residues; MW, C, .. pp is the range of measurement of the ordinates; C /, f modules or capacitance counters ADC; -ortogonal bases of the system of residual classes; ha ,. - the weight of the orthogonal basis, determined from the relation S-igf- - eic, is a positive integer. The capacitance of the ADC counter is changed with the help of keys that are controlled from the CU through the decoder W. In the initial state, before starting the measurements, the triggers jTy, TjT are set to O. Then, the number of pulses corresponding to the ordinate value is input to the ADC counter. y (fig. 2). At this, the counter performs cyclic overflows (turnovers), after which it stops at an incomplete filling, the value of which is equal to the remainder of dividing the number of pulses received at the input of counter A. C-1 (ksg 2 - 1). Then the input of the meter of the control unit is fed from the start-up register generator 4 (FIG. 1) to a pulse that changes the state of the counter of the control unit. The latter changes the state of the keys through the secondary key in such a way that The incoming impulse to set the ADC counter to 0 sets it to state C and the number of pulses corresponding to the ordinate value yj is fed to the input of the ADC counter.When counting pulses, the ADC counter also performs cyclic overflows. After each overflow, a pulse appears at the output of the ADC counter, which sets the counter to the state C through the corresponding keys ... As a result, when the ordinate is measured, the capacitance of the counter ,, Z -1 - g TTP 2 kA ADP is equal to C. at the end of cyclic overflows, the ADC counter registers the remainder of dividing the number of pulses corresponding to the ordinate y, by the capacitance Cr. When measuring ordinates

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““ .F 1 V, similarly, with the pulse of the generator of the start-registration generator, the ADC counter is set to the state, respectively, d, s ;, .... s; and cyclic overflows the ADC counter performs, I L. Grip capacitances (Ja - r1 Sdlaks С -4 max t, “Then, when measuring ordinates, the capacity of the ADC counter is set to q, csI I described, the process of changing the capacitance of the ADC counter is repeating In the next period of the process, the measurement of the ordinates y, y fn i / tim yr .-- m 7 y is carried out with the capacities of the ADC counter, respectively, equal to С, -, 0, - + ..., 2. , at the end of a set of information, each sample of the process y (t) is represented by a set of residues Sy, Sj, ... I, S f ,.

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Claims (1)

STROBOSCOPIC PRESSURE INDICATOR No. 618669, which includes the fact that, in order to expand the measurement range and improve accuracy, a counter capacity control unit for the analog-to-digital converter is introduced into it, the control input of which is connected to the output of the capacity control unit of the counter of the analog-to-digital converter, and the control input the latter - with the output of the pulse generator start registration,, G SU,. „1174801 1 .1174801