SU734775A1 - Shaft angular position-to-code converter - Google Patents

Description

one

The invention is automatic and computerized and is intended to convert the angle of rotation of the shaft into a digital equivalent.

It is known that precision angle-code converters are usually reversed as two- or three-count systems, since improving the accuracy of a single-digit converter is limited by the technological difficulties of manufacturing the coding element (QE), the instrumental error of analog nodes, and the limiting quantization error determined by the boundary the speed of logic circuits, forming the reference part of the converter.

Measuring the angular position of the shaft with the help of multitouch transducers makes it necessary to coordinate neighboring readings in order to eliminate measurement errors equal to the weight of the least significant coarse reading (GD). To agree The reading of readings corrects the readings of the GO channel based on the results of the analysis of the readings of the GO channels and the exact readout (TO). The analysis of the readings and the adjustment carried out from the matching device, the logic of which is determined by the method adopted in the converter, to obtain the numerical equivalent of the angle.

One of the most common methods of converting an ambient into a code involves pre-transforming the angle into a change in the phase of an electrical signal and then into a time interval filled with stable frequency pulses, the number of which will be proportional to the desired movement of the shaft | l.

Claims (2)

The angle code in such converters is generated using HO and TO counters. The essence of the sample matching is that a matching bit (CP) is entered into the converter and the need to introduce an amendment to the GO is determined by a logical analysis of the indications of the higher bits of the TO and the CP, which is combined with the zero of the TO and the GO, which is achieved by the initial setting of the phase-shifter. with respect to the stator, so that the zero of GO coincides with any zero of it. The correction in the e-code case is entered by algebraically adding one with the GO indications, and for introducing the correction, the converter is supplied with combinational adders whose number is equal to the number of bits in the GO counter. In this case, there is no need for combinational adders. A further simplification of the matching device and the converter as a whole is achieved by organizing the zero shift of the GO relative to the zero TO by an angle equal to half of the matching zone. The block diagram of such a converter contains exact and coarse phase shifters interconnected, each of which is respectively through the first and second null - the detectors are connected to one of the inputs of the corresponding triggers, the outputs of which are connected to the first inputs of elements I. The output of the first element I is connected to one of the inputs From the counter of the exact readout, and the output of the second element I to the first input of the block for matching the readings. The power source is connected to phase shifters of precise and coarse readings, to the third zero detector and multiplier, the outputs of which are connected to the second inputs of elements I. The output of the third zero detector is connected to the input of the third trigger, the first output of which is connected to other inputs first and second triggers and co. the second input of the sample matching unit. The second output of the third trigger is connected to the third input of the sample matching unit, the output of which is connected to one of the inputs of the coarse count counter. The output of the counting counter is connected to the fourth flow of the sample matching unit 21. The known transducer has drawbacks. To obtain at the output of the converter a code corresponding to the angle of rotation of the shaft, it is necessary to combine the zero of the phase shifter TO with the zero of the shaft, and phase the rotator TH to set to such a position where the pulse increments of angle in the HO channel will be emitted in neighborhoods of points (2K + ), g (1) where K is the number of half halves of the poles of the TO sensor that fit into the angle I. To create a similar exhibition and accurately fix the phase shifters in the desired position only with the help of a mechanical unit that complicates the mounting of the stators and inserts gross error in the total error of the converter. In addition, recently, combined-type sensors, such as rotary transformers, in which the windings of TO and GO have a common magnetic core, have become used as phase shifters. In the case of the use of such phase shifters, it is impossible to carry out the mechanical turn of the phase shifter with respect to the phase shifter, since they have a common stator and rotor. The aim of the invention is to increase the reliability by expanding the permissible misalignment zone between the zero of the shaft and the zero of the exact counting phase shifter, as well as between the rough counting phase and the exact counting phaser by introducing corrections taking into account the true position of the phasers, into the GO and TO counters during initial installation and corrections to the resulting code. The goal is achieved t & l, that in the converter of the angle of rotation of the shaft in the code, the sealing devices and the adder are entered. The output of the first storage device is connected to the first input of the adder, the first output of the third trigger is connected to the input of the second and third transfer devices. The output of the second memory device is connected to another input of the counter of the exact count, the other outputs of which are connected to the second input of the adder. The first output of the third jamming device is connected to the horny input of the coarse counter to the fifth input of the sample matching unit, the output of the coarse counter is connected to the third input of the adder. The block diagram of the converter is shown in FIG. 1, in FIG. 2 is a diagram illustrating the definition of ps grass codes. The noBqDOTa angle converter of shaft 1 contains (see Fig. 1) a power source 2, a precision phase shifter 3 (PHTO), a phase calculator 4 coarse on counting (CVF), null detectors 5-7, triggers 8-10, multiply frequencies 11, elements AND 12, 13, meter 14, TO, counter 15 GO, block 16 matching samples, which consists of the element AND 17, triggers 18 and 19 and elements OR 20, 21, storing devices (memory) 22-24 25. As a FEGO, any C1-cosine angle sensor with one pair of full ones can be used: s (p 1); as an FWTO, both a sensor with a p 1, connected to the input shaft through a gear train, and a multi-pole angle sensor, which is preferable. The rotors of the WCF and FCH are rigidly connected to the input shaft. The stators are positioned relative to each other and their rotors in this way. So that in the initial state of the zero shaft, the current state fell into a null of the VPTO, and the zero CVT fell behind the zero of the shaft by one quarter of the TO. POLAR DIVISION WORKS AS FOLLOWS Converter. The rotors of PHVTO 3 and PHEG 4 are fixed on the shaft 1, the stats of the phase shifters are positioned relative to their rotors and relative to each other in an arbitrary manner. To determine the correction codes entered into the memory 22-24, the shaft 1 is turned to the zero position and it is determined how much the leading zero TO is offset relative to the zero of the zero shaft (see Fig. 2). It is possible to make such a measurement with the help of a converter, measuring, for example, the duration of time intervals formed by triggers 9 and 10 between the start and stop pulses. These spacing1 will be proportional in the GO channel — the angle of rotation of the zero FVGO 4 relative to the zero of the shaft and in the TO channel — the angle of rotation of the shaft that is closest to the Kul of the advancing shaft, the zero of the PHTO, i.e. g / - -2et:. 0- (Tm is where Sgo1C | o- measured lengths of the belt intervals in the GO and TH channels are cooTBeiCBeHHo ;; voltage supply voltage phase shifters; googol misalignment between zero shaft 2 and GO ;; .0 misalignment angle between zero shaft and the nearest leading shaft Zero; P is the number of pairs of poles of the PHTTO. The choice of correction codes is made as follows (see diagram in Fig. 2). 73 and 56 To match the samples, the zero of the GO must be shifted to the zone of matching the samples, i.e. in the first half of the first (counting from the zero of the shaft) poles TO. Therefore, the code of the amendment to the account The GO chip (matching bit) is equal to the number K, from the equality K (1) - Cros, (3) where the number of significant bits in the GO counter; the number of bits in the GO counter, including the matching bits; 2 -1 is the maximum number fixed in the GO counter (in conjunction with the matching bit), the number of full halves of the TO sensor poles being laid in the corner. The misalignment angle between the shaft zero and the GO corrected zero (angle), as shown in FIG. 2 is equal to: ft -, 4) Pro о V go-cho the remainder of the SL, after you read from it K the halves of the poles of the TO sensor. To perform the matching operation, it is also necessary that, in the initial position, the zero TO.c equals the zero of GO by one quarter of the pole division of the TO, i.e. zero TO must occupy the position indicated in FIG. 2 as adjusted for TO. Therefore, the loyravki code in the maintenance counter must correspond to the angle i-, equal to - (then A-In gto 2.R Correction to the resulting code is necessary to combine the corrected zero TO with the true zero of the shaft. This amendment should correspond to the angle. Corrections are entered into the memory once, when the converter is being adjusted, and the whole operation time is kept if the sensors are on the shaft during this period. It is reinstalled. The code of the correction in memory 23 is equal to the number K J - the integer in memory 22N ,, K, where the number of discretes placed in the corner of the packing T is equal to. The discrete converter is considered the cost of the reference value, determined by the equality of cS-hea n total number of bits in account chikah TO and GO, excluding the discharge agreement. A cop of the amendment to charger 24 is equal to the number of "M" where is an integer number of piscrites placed in a corner. For example, valve groups, e.g. performed on a series 134 microcircuit, the potential inputs of which are permanently connected to 5V buses or about & dy depending on which I or O should be stored in this cell. When applying to the second inputs of the elements And a pulse of interrogation at the outputs of the elements And there appears a pulsed coa corresponding to the number stored in this memory. When reinstalling the phasers on shaft 1, new corrections coi are entered into the memory by re-switching the memory busses. After making corrections to the charger, the converter is ready for operation. On the output signals of the power source 2, taken as a cp voltage and described by the equality 1 e) t, B null petector 5 w, the output sets are x pulses that coincide in time with the signal transition times Ujj from zero from the negative half-wave to positive, which affect the counting input of the trigger 8. Every two pulses arriving at the counting input of the trigger 8 are outputted from its outputs one start pulse and one co-pulse each time, and if the start pulse s is given input them pulse, then the matching pulse is output for each even input pulse {or vice versa). A star pulse is always separated from the matching pulse for a time equal to the duration of the onqpHoro voltage. From the start pulse, a conversion cycle begins. Zero detectors 6 and 7 form stop pulses at time instants coinciding with the points of zero crossing of signals from the negative half-wave to positive. The conversion cycle starts with a star pulse. The start-impulse performs recording in counters 14 and 15 of the TO and GO codes of amendments from memory 22 and 23. In addition, the strat-kn pulse sets the trigger 19 of the matching block to zero, and 73 5 the trigger 18, which is the match , in the state O or 1, depending on the code of the correction in memory 23. If the number Kd, determined from equality (3), is four, then in the lower category of memory 23 there is a zero and trigger 18 is set to zero by the start pulse to zero, and if K d is odd, then in the low-order de zU of memory 23 is the unit and the trigger 18 is set to one for the strata pulse. The need for such an installation of the trigger 18 is connected with the fact that only whole poles can be fixed in the TO 15 counter, and half of the poles are fixed in the matching category. The star-pulse also sets the triggers 9 and 10 into the unit, thereby allowing the passage of the filling pulses from the multiplier frequency 11 through the elements 12 and 13. As a result, codes 14 and 15 begin to form codes corresponding to the angles of rotation of the shaft 1 counted not from the true phase shifters, and from their adjusted positions. Stop impulses set the trigger; 9 and 1O are in the zero state, and the And 12, 13 elements are closed. The first conversion cycle ends there. Codes are recorded in the GO and TO counters. psi1or1daonal angles of rotation of the shaft, counted from the adjusted zeroes of phase shifters. In order to obtain in the counters 14 and 15 a number proportional to the angle of rotation of the shaft relative to a common reference point coinciding with the corrected zero TO, a matching operation is performed, i.e. matching pulse, generated in trigger 8, passes through the element 17, if the most significant bit of the TO 14 counter is after the end of the first conversion cycle in the state O. The matching pulse, which passed through the element 17, is added to the contents of the GO 15 counter only , if at the end of the first conversion cycle, trigger 18 remained in state 1, and trigger 19 in state O. To obtain at the output of the code converter a number proportional to the angle of rotation of the shaft relative to the true, not offset zero, shaft, p The resulting code is output to the computing device through the adder 25, which performs the algebraic layer (Live code correction code Y, with the code of the number recorded in the counters 14, 15 after 973 rie matching operations. The formula of the invention of the angle of rotation of the shaft kotz containing exact and coarse phase shifters, interconnected, each:, the first of which, respectively, through the first and second null detectors are connected to one of the inputs of the corresponding triggers, the outputs of the They are connected to the first inputs of the elements And, you, the stroke of the first element And are connected to one of the inputs of the counter of the exact count, and the output of the second element I to the first input of the block of the sample matching, the power source is connected to the phasers of the exact and coarse readings, to the third a null detector and a frequency multiplier whose outputs are connected to the second inputs of the AND elements, the output of the third null detector is connected to the input of the third trigger, the first output of which is connected to the other inputs of the first and second triggers and to the second input ode of the sample matching unit, the second output of the third trigger connects with the third .. input of the sample matching unit, the output of which is 28 27 751.0 th is connected to one of the inputs of the coarse counter, the output of the counter of the exact readout is connected to the fourth input of the sample matching unit, characterized in that, in order to increase the accuracy of the converter, the ycTpoiiCTBa and the adder, the output of the first memory device, are entered into it edpr1en with the first input of the adder, the first output of the third trigger is connected to the input of the second and third memory devices, the output of the second memory device is connected to another input of the counting meter of the exact count, other outputs first connected to the second input of the adder, the first output of the third storage device is connected to another primary coarse counting counter and the fifth input of the sample matching unit, the output of the coarse counting counter is connected to the third input of the adder. Sources of information taken into account in the examination 1.Zverev AE. Angular displacement transducer into a digital code. L., Energie, 1974, p. 153-156. 2. Zaeolokin A. K. Sequential converters of continuous quantities into numerical equivalents. M., Gosenergoizdat, 1962, p. 61-63 (prototype). four f R