SU480100A1 - The converter of an angle of rotation of a shaft in a code - Google Patents

Description

one

The invention relates to the field of automation, and in particular to devices for automatic control and monitoring.

A known angle-code converter, a pulse generator, a multi-bit scale binary circuit, a synchronous biii multiphase voltage source, a phase shifter, a phase pulse driver, and a coincidence circuit are known.

The disadvantages of the known converter are low reliability and accuracy.

In order to eliminate these drawbacks, a frequency multiplier, separation units for positive and negative readout pulses are introduced into the proposed converter. The phase shifter and frequency multiplier are connected directly to a variable voltage power source. The first input of the frequency divider is connected to the output of the positive sampling pulse selection unit, the second to the output of the frequency multiplier, the third to the output of the negative sampling output unit, the fourth to the output of the zero allocation unit and one of the inputs of the selection pulse unit. The first output of the frequency divider is connected to another input of the allocation unit of the selective counting pulses, and the second - to another input of the selection unit of the negative counting pulses.

FIG. 1 shows the structural scheme of the proposed converter.

The converter contains a frequency multiplier 1, a frequency divider 2 with a discretely varying division factor of +1, a selection unit for positive counting pulses 3, a selection unit for negative counting pulses 4, a phase shifter 5, and a selection unit zero 6.

FIG. Figure 2 shows the output timing diagrams of the operation of converter elements for a frequency multiplier factor, m -8.

FIG. 2, and the time diagram of the operation of the frequency multiplier is indicated; 2.6 is the source of the thread with a frequency of co; 2, в - phase shifter; 2, g - block allocation zero; 2, d - output I frequency divider (first large-scale grid); 2, e - output II of the frequency divider (the second wide grid); 2, W - unit for the selection of negative counting pulses; 2,3 - block selection of positive reference pulses.

The Converter operates as follows.

The supply voltage of the form t / osin () (Fig. 2, b) is applied to the inputs of frequency multiplier 1 and phase shifter 5. From the output of the frequency multiplier, clock pulses with frequency fn-fn are fed to input II of frequency divider 2.

A voltage of the form / 151p co / + f1 (/) from the output of the phase shifter (Fig. 2, c) is supplied to the allocation unit pool 6, from the output of which pulses with a frequency of modulating voltage are followed (Fig. 2, d). From the output of this block, the pulses arrive at the second inputs of the block for selecting the reference pulses 3, 4 and on the input IV of the frequency divider.

2, with the first pulse includes a frequency divider.

From outputs I and II of frequency divider 2, the pulses of the first and second scale grids are displaced one with respect to the other by 2 m,

where is the clock period

/"Yes

(Fig. 2, c and 2, e).

The pulses of the scale grids are respectively fed to the inputs I of the allocation units of positive and negative counting pulses 3, 4. Moreover, when the frequency divider 2 is turned on, the pulses of the scale grids take such a position that the pulses of the allocation unit zero 6 fall into the interval 2, caused by the offset between the pulses of the grids (Fig 2, g, 2, d and 2, e).

Obviously, in this case, the pulses of the allocation unit zero 6 alternate at the inputs of the selection units of the reference pulses 3, 4 with the pulses of the scale grids, and there are no pulses at the outputs of the blocks 3, 4.

Each block 3, 4 is designed in such a way that the counting pulses at the input appear only if one of the inputs (any) has two pulses of the order, one after the other, and the second impulse causes the appearance of the output impulse.

If the phase shifter is not fixed, then the frequency of the arrival of pulses from the output of the zero allocation unit and the scale grids from the outputs of divider 2 are equal and the pulses are fixed one relative to another.

Suppose that the rotor is phase-shifted, the tel 5 rotates in the direction in which the frequency of pulses arriving at the inputs of blocks II

3.4 from the output of the allocation unit zero 6 decreases, i.e., the pulses from the output of block 6 are shifted to the right relative to the pulses of the scale grids from frequency divider 2 arriving at the inputs I of circuits 3, 4 (Fig. 2, g, 2, g and 2, e).

 only the rotor of the phase shifter will rotate at such an angle that the pulses from the output of block 6 are shifted to the right so that their alternation with the pulses of the second scale grid is disrupted, and at the inputs of block 4 so that two pulses 3 and 4 (5 and 6) of the second scale grid ( Fig. 2, e) is received at the input I of block 4, then the second of these pulses 4 (6) will cause the output of this block (at the output of the converter) of the read pulse containing information about the angle of rotation of the shaft (c | ) ig. 2, f, times ti (/ 2).

In addition, from the output of block 4, this pulse arrives at the input III of frequency divider 2, after which the latter emits the following pulses of scale grids not after a period equal to m-t, but after a period of (m-j-l) t. In this case, the pulses of the block 6 are alternated again with the pulses of the scale grids at the inputs of the blocks 3, 4.

After working off one extended period, frequency divider 2 continues to give impulses of large-scale grids with a period equal to тт :.

When the rotor of the phase shifter 5 rotates in the opposite direction, the frequency of pulses arriving at the inputs P of blocks 3, 4 from the output of the allocation unit zero 6. increases, i.e. the pulses from the output of block 6 are shifted to the left relative to the pulses of the scale grids from frequency divider 2 (Fig. 2 g

2, d and 2, e).

As soon as the rotor of the phase shifter is rotated at such an angle that the pulses from the output of the block, the selection 6 is shifted to the left so that their alternation with the pulses of the first scale grid at the inputs of the block 3 is disturbed, so that two pulses 9 and 10 from the output of block 6 (Fig. 2 , d) an additional input is sent to the input II of block 3, then the second of these pulses 10 will cause the output of this block (to

the output of the converter of the reference pulse, containing information about the magnitude of the angle of rotation of the shaft (Fig. 2, at the moment of time t). In addition, from the output of block 3, this pulse arrives at the first input of frequency divider 2, after which the last produces the following pulses of scale grids not after a period equal to tni, but after a period of (t -1) t. In this case, the pulses of block 6 again alternate with the pulses of scale grids at the inputs

blocks 3, 4.

After working off one shortened period, frequency divider 2 continues to generate pulses of scale grids with a period equal to mt.

Thus, when a counting pulse appears at one of the transducer outputs, the pulses of the main grids are discretely shifted towards the shift of the pulse of the allocation unit zero 6 relative to the pulses

scale grids.

It is also obvious that each reference (output) pulse of the converter corresponds to the rotation of the rotor of the phase shifter, and hence the shaft, by one quantum of the angle K, equal to

2t.

/. -,

rt

where p is the number of pairs of poles of the phase shifter; ,14.

From the above description and timing diagram (in Fig. 2), it is clear that the maximum frequency at the output of the converter cannot exceed half the frequency of the supply voltage / n / 2, since only in this case the necessary shift of the scaled grids can be made. Therefore, the maximum permissible speed of the phase shifter can be defined as the product of the angle quantum by half the frequency of the power supply / n D- / P 2 rt. From the formula (1) it can be seen that to increase the somax it is necessary to increase the frequency of the power supply. The subject of the invention A shaft rotation angle converter into a code comprising a phase shifter, the output of which is connected to the input of the allocation unit zero, and a frequency divider, characterized in that, in order to increase the reliability and accuracy of operation of the converter, a frequency multiplier, allocation units positive and negative are entered into it counting pulses; wherein the phase shifter and frequency multiplier are connected directly to a variable voltage power source; the first input of the frequency divider is connected to the output of the positive dead pulse separation unit, the second to the output of the frequency multiplier, the third to the output of the negative sampling output block, the fourth to the output of the zero allocation unit and one of the inputs of the selection pulse pulses; The first output of the frequency divider is connected to another input of the positive pulse selection unit, and its second output to another input of the negative sample pulse output unit.

Output

Output

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