×

Flow control device

  • US 5,983,937 A
  • Filed: 02/04/1997
  • Issued: 11/16/1999
  • Est. Priority Date: 02/05/1996
  • Status: Expired due to Fees
First Claim
Patent Images

1. A flow control device for controlling fluid flowing in a fluid passage, comprising:

  • a valve body disposed within said fluid passage, said valve body having a shutoff portion for prohibiting flow of fluid and a first and a second opening for allowing flow of the fluid, said second opening being smaller than said first opening, said valve body being movable between a first position in which said fluid passage is fully closed by said shutoff portion, a second position in which said fluid passage is opened by said first opening and a third position in which said fluid passage is opened by said second opening;

    valve body operating means for moving said valve body between said first, second and third positions; and

    control means for electrically performing a first duty control for said valve body operating means, said first duty cycle comprising repeated movement of said valve body between said first position and said third position, said valve body remaining in said first position for a first specified time period and said valve body remaining in said third position for a second specified time period.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×