Patents Assigned to Thompson Manufacturing Co.
  • Patent number: 4206901
    Abstract: A metering apparatus for controlling the rate of closure of a pressure-actuated valve of a type normally used in irrigation systems. When a pressure-actuated valve is closing, fluid from a supply line must flow into a pressure-actuating chamber, gradually filling it to force the valve's plug member against its seat. The metering apparatus is a compressible spring through which fluid must flow to enter this pressure-actuating chamber. As the valve closes, it compresses the spring through which the fluid must flow, thereby restricting the rate of flow into the pressure-actuating chamber. This reduction in flow reduces the rate at which the valve's plug member approaches its seat in an exponential manner, allowing rapid closure at first which is reduced considerably as the plug approaches its seat.
    Type: Grant
    Filed: October 11, 1977
    Date of Patent: June 10, 1980
    Assignee: Thompson Manufacturing Co.
    Inventor: Tom Williams