| 摘要 |
FIELD: food industry.SUBSTANCE: food products quality express evaluation device includes piezoelectric converters with probes, a high frequency generator, a low frequency pulse generator, a mixer, an amplifier, an output signal converter and an information display unit. The mixer is designed so that to enable generation of a signal at the output for shear surface waves excitation. For this purpose, the first input is connected to the low frequency generator via a former of pulse impact designed so that to enable low frequency rectangular pulse supply; the second input is connected to the output of the high frequency sinusoidal oscillations generator. A meter is connected to a binary-decimal decoder the output whereof is connected to the information display unit, the unit designed in the form of a liquid-crystal indicator. The mixer output is connected to the first converter (from the five converters) placed in the contact head centre and being the source of shear surface waves the receivers whereof simultaneously represent the four other converters (installed along the circumference at an identical distance from the central one) the outlets whereof are connected to the amplifier in the form of a summing amplifier. The amplifier is connected to the output signal converter including an integrator connected to the input of the Schmitt trigger the output whereof is connected to the trigger input for stopping counting.EFFECT: quality evaluation simplification and reliability improvement.2 dwg |
