| 摘要 |
<p>The appts. has an AC generator (112) followed by an amplifier (113) to power a probe coil (114) part which passes piece parts (116) under test. The probe output is amplified (118) and applied to a Fourier analysis circuit (120). This comprises an A/D converter (126) whose output is entered into a RAM (128). The sampled data is applied to a calculator circuit in which a PROM contains data blocks for harmonic coefficients of the samples in the RAM. - A counter provides addressing control and enables the sinc or cosine series algorithm to be selected. A multiplexer output is passed to an accumulator to produce the real and imaginary parts of the harmonics. A microprocessor provides control through a sequencer for all the operations and the resultant output (122) is processed (124) to operate an ejector (125) for the piece. USAB- US4630229 A The circuit comprises an analog-digital converter, a random access memory, and calcuating means comprising a PROM, a counter, a multiplier, an accumulator and a sequencer. The sequencer circuit is able to transmit pulses to the counter, to control the reading of the samples in the acquisition memory and, simultaneously, the reading in the block of the coefficient memory of the coefficients cos 2 pin/N. The reading of the samples in the acquisition memory is controlled as to the simultaneous reading in the first block of the coefficient memory of coefficients sin 2 pin/N and for each reading of the sample and a coefficient, to control the multiplier and then the accumulator and then reiterate the controlling and reading with the second block of the coefficient memory and so on up to the last block is controlled by the circuit.</p> |
