CS205755B1 - Connection for feeding the phase convertors at measuring the position on the machine tools - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a circuit for supplying phase converters suitable in particular for measuring positions on machine tools.

Two voltages of the same amplitude phase shifted by 90 ° are used to supply the phase converters. These voltages have either sinusoidal or rectangular waveforms of 1: 1 duty cycle. Both of these methods have some disadvantages. For sinusoidal power supply, the accuracy depends on both the phase shift accuracy of the 90 ° excitation voltages, the exact setting of their equal amplitudes and the shape distortion of these voltages. Compliance with these criteria is circumferentially demanding in this type of power supply. Rectangular power supply eliminates many of these disadvantages, but requires a high-quality filter to eliminate higher harmonic frequencies at the output of the phase converter. The content of higher hormanic frequencies in the output signal of the phase converter is very high in this type of power supply, which adversely affects the achievable accuracy of the evaluation of the position of the converter.

Many of these disadvantages are overcome by the circuitry of the present invention, wherein the state counter output is coupled to a constant memory input whose first output is coupled to a first programmable counter input, the second constant memory output is coupled to a gated input of a phase flip-flop block. Y, the third constant memory output is coupled to the gate input of the phase X flip-flop block, the frequency source output is coupled to the second input of the programmable counter, the output of which is interconnected with the input of the I / O counter. X and Y, the flip-flop block output if X is connected to the phase X amplifier and the output of the phase-flip flip is coupled to the phase Y amplifier input, where the X and Y phase amplifier outputs are coupled to the X and Y inputs phase converter, the output of which is connected to the the filter stage and the filter output is connected to the input of the position evaluation block.

The advantage of the circuitry according to the invention over the current phase converter power supplies is that the phase offset and the equivalence of the excitation voltage amplitudes are maintained just as accurately as the rectangular power supply, but the phase converter output signal has an order of magnitude lower harmonic frequencies. and simplifies circuit control, in particular of the inverter output signal filter.

An example of power supply connection of phase converters according to the invention is shown in the figures. Giant.

FIG.

An example of a phase-to-phase excitation voltage waveform is shown.

In the block diagram, the output of the status counter 1 is connected to the input of the constant memory 2, the first output of which is connected to the first input of the programmable counter 4, the second output of the constant memory 2 is connected to the gating input of block 6 of phase. the constant is connected to the gating input of block X of the flip-flop of phase X, the output of the frequency source 3 is connected to the second input of the programmable counter -4, the output of which is connected with the input of the state counter 1 and the change inputs of blocks 5, 6 and Y, the output of Phase X flip-flop block 5 is connected to the input of Phase X amplifier 7 and the output of Phase Y flip-flop block 6 is connected to the input of Phase Y amplifier 8, the outputs of Phase X, Y amplifiers 7 are coupled to the inputs phase X and Y of the phase converter 9, the output of which is connected to the input of the filter 10 and the output of the filter 10 is connected to the input of the block 11 ' pooioihy.

The clock frequency from the frequency source 3 is fed to the input of the programmable counter 4, since it is divided by a number 1 and assigned to its input for parallel adjustment from the output of the 2 constant memory. The address of this memory is determined by the content of the jump counter 1. The output signal of the programmable counter 4 changes the status of the status counter 1 and is also connected to the changeover inputs of the flip-flops 5 and 6 of phases X and Y. The remaining two outputs are 2 constant memories. un & uij.í, Ikterry iz. The flip-flops 5 and 6 are supposed to change their state when the changeover signal is received. The phase excitation signal X and Y thus formed has, for example, the shape shown in Figure 2. This signal has a content of higher harmonic frequencies which have a significant influence on the position evaluation accuracy, substantially lower than the rectangular signal. The output signal of the flip-flops 5 and 6 of the phases X and Y, after amplification in amplifiers 7 and 8 of the phases X and Y, is applied to the input of the phase converter

9. The output signal of the phase converter 9, whose phase is proportional to the position, is devoid of higher harmonics in the 10th sinusoidal filter. the signal at the output of the filter 10 represents input information for the position evaluation block 11.

Claims (1)

SUBJECT Circuit for power supply of phase converters for position measuring on machine tools, characterized in that the output of the status counter (1j is connected to the constant memory input (2), the first output of which is connected to the first input of the programmable counter (4), ) constant is connected to gate input of block (6) of phase Y flip-flop, third output constant memory (2) is connected to gate input of block (5) of flip-flop. phase X, output of frequency source (3) is connected to second input of programmable a counter (4) of which YN ALEZU output is connected both to input of state counter (1) and to change inputs of phase and flip-flops blocks (5, 8), phase output of flip-flop phase (5) is connected to input of amplifier (7) of phase X and the output of the phase Y flip-flop block (6) is coupled to the input of the amplifier (8J of the phase Y), the outputs of the amplifiers (7, 8) of the phases X and Y being connected to the inputs of the phases X and Y. The output is (if connected with the iTtrium t (111)), and the filter output (10) is ipjmpojjlein is a location evaluation (11).