| 摘要 |
<p>An apparatus and method for controlling the flow rate of refrigerant to a refrigeration device is provided. The system includes a mixing chamber (18, 20) that retains and produces the product, a compressor (54) and an evaporator (60, 62) secured to the exterior of the mixing chamber for providing freezing of the product being produced within it. The system further includes an expansion valve (66, 68) coupled to the evaporator that regulates the flow of the refrigerant through the evaporator. A scraper (38, 40) rotatably mounted within the mixing chamber is provided for scraping the frozen product from the interior surface of the mixing chamber. A beater motor (46, 48) rotates the scraper. An electronic control (14) is provided for controlling the refrigeration cycle. The electronic control employs a microprocessor which is operated in accordance with an algorithm for controlling the operation of the expansion valve. The microprocessor periodically receives signals from the beater motor indicative of the viscosity of the product being produced within the mixing chamber. The electronic control transmits signals to turn the compressor on and off and adjust the position of the valve in response to the signals received from the beater motor so as to control the rate of refrigerant flowing through the evaporator.</p> |
