SU658706A1 - Arrangement for shaping reference of harmonic signals - Google Patents

Description

(54) DEVICE FOR FORMING SUPPORT HARMONIC SIGNALS

This invention relates to the conversion of non-electric bodies. values in electric harmonic signature. Arrangements for supporting harmonic signals are known, containing disks on which transparent and opaque areas are located, or teeth with disks and sensors connected via an amplifier-limiter to the first harmonic generator of the electrical signal l. The disadvantage of such devices is the difficulty of making the forming unit, which reduces the reliability of the device. The closest in technical solution to the present invention is a device for forming operatic impulses, which contains a tag with a label fixed on the shaft and a sensor connected through an amplifier-limiter to the integrator 2. The disadvantage of this device is also relatively low accuracy. improving the accuracy of the device for forming reference harmonic signals. This goal is achieved due to the fact that in the device the tags are located along the perimeter of the discs in I equal sectors, and the length of the marks within each sector is 1/2) where 1 is OD, 2 ..., (AND -1 ). FIG. 1 shows a block diagram of the proposed device; in fig. 2 is a diagram illustrating the operation of the device. A device for generating reference harmonic signals (see FIG. 1) contains a disk 1 with marks 2, a sensor 3, an amplifier-limiter 4 and an integrator 5. The disk 1 is fixed on the shaft, which causes the rotation of the Prn to rotate the disk 1 of the label. 2, applied along its perimeter according to a certain law, passes by the sensor .3, which produces an electrical signal. The latter is amplified and limited in amplification.

it is integrated into integrator 5. The labels can be phase mechanical, made in the form of recesses and protrusions around the perimeter of the metal disk or light-contrast. In the first case, a magnetic head is used as a sensor, in the second photo head. The signals received at the output of the amplifier-limiter 4 have a certain shape and law of change, which are determined by the law of marking marks 2 along the perimeter of the disk 1.

Let disk 1 be divided into 1.2 sectors. In sector 1 (see Fig. 1), from left to right, there is a light-contrast mark (shaded area), then a gap equal to the length of the mark, again a mark, etc. When sector 1 passes by the reference sensor 3, if the disk is rotated counterclockwise and the amplifier-limiter 4 connected to sensor 3 is received, an electrical signal is generated, one period of which is shown in FIG. 2, a, which is a direct symmetrical voltage (square wave). Here conditionally, the presence of a label corresponds to a signal with an amplitude of + 1, and the gap (i.e. no label) corresponds to a signal with an amplitude of 1. The average value of such a signal is O, which follows (see Fig. 2, a) from the equality of areas above and below the mean value line (marked with a dashed line) v For the signal shown in FIG. 2, a, the lines of the mean and zero value coincide. The electrical signal corresponding to the marks in sector P is shown in FIG. 2, b; in this case, the length of the mark is three times the length of the gap. The average value of such a signal is O, 5OO. In sector 111, the length of the label relative to the length of the gap is chosen such that the average value of the signal (see Fig. 2., c) is equal to 0.866. There are no gaps in sector IV; the corresponding signal (see Fig. 2 g) has an average value of 1, LLC, etc.

Note that the values of these average values are equal, respectively, to the values of ripos of the angles o, i, 30, 6O, 90, and t, d. Thus, when the disk rotates, the output of the sensor 3 produces pulses of different duration, and their average values vary sinusoidally with a frequency equal to the rotor rotation frequency.

i.e., pulse width modulation (PWM) takes place. The accuracy of the formation of a sinusoidal law is determined by the accuracy of forming the values of individual angles. Therefore, the more the disk is divided into, the closer to the sinusoidal the law of change will be. The total length of the label within the sector is calculated under the condition that the disk is divided into AND sectors. Denote by Y the part which is the total length of the mark within the arc of the sector along the perimeter of the length of the arc - 2TCR

where R is the radius of the disk

gi sector

P

then the expression for -J is:

2ll

i

T Td + sin-pi O; 1st, - (, 2 ... Si-1)

With 1 AO 3-0.5, t. e. half of the total length of the sector G along the perimeter (this length

where R is the radius of the disk) is equal to

Claims (2)

Understands the label, and the other half is a gap. This means that sector I corresponds to a square electric signal of the square wave type. With 1 1, 75. In this case, in sector I, the total length of the label is 3/4 of the whole arc within the sector, i.e., the electrical signal corresponding to sector II is as shown in FIG. 2, b. When, ZZZO, 933, i.e., most of the arc length of sector III along the perimeter is occupied by a mark (more than 0, 9), the gap remains 0.67 of the entire perimeter within the sector. The average value of the electric signal (see FIG. 2, c), corresponding to the IJI sector, is equal to 0.866. The verification of the mean value is very simple: it must be ensured that the area under the line of the mean value is equal to the area above it. Having received (see Fig. 2, c) that the pulse width is equal to two, the area above the curve (1-0.86 xO, 933 must be equal to the square of the lower part (1 + 0.966) xO, O7, i.e. these the areas are equal to each other and equal to the number 0.125022. Thus, it can be seen that the choice of label length in sector III equal to O, 933 from the perimeter within the sector, results in a number for the average value of the electrical signal equal to 0.866, which corresponds to Sin6O. In sector IV (1, 3), the entire arc length of the sector along the perimeter is occupied under the label. Consequently, the average value of the corresponding signal is equal to 1. All the values 5, 6 or for the part that is the mark length within the sector from the entire perimeter can be obtained. Thus, with the selected partitioning of disk 1 into a known number and the selected value of the radius R, the arc length of the sector around the perimeter is equal to / i-. Then, the mark length is calculated, it is equal for each ltR of each sector. Thus, the reference signal is formed as a sequence of impulses of fixed amplitude, the duration of which is sinusoidally from the law, so the average values obtained signals are also changed sinusoidally with a frequency equal to the frequency of rotation of the rotor. Integrating this latitude-modulated signal over time by integrator 5 receives a sinusoidal voltage. 066 The invention The device for forming the reference harmonic signals containing a tag with tags attached to the shaft, a sensor connected via an amplifier-limiter to the integrator, distinguishes itself with the fact that, in order to improve the accuracy of the device, the marks are located along the perimeter of the disk in And in the sectors, and the length of the labels in the distribution of each sector is l / 2j (t-fr5itl 1 "O.lJi ... (P-1). Sources of information taken into account during the examination 1.Agaykin DI and Other sensors of control and regulation, M., Mashinostroenie, 1965, pp. 46O-467. 2. The patent of Germany No. 2122967, cl. Q O1 M 1/22, 1971. FiL