| 摘要 |
A fuel control system, throttle valve unit therefor and methods of making the same are provided, the system comprising a burner, a source of fuel for the burner, and a throttle valve unit for interconnecting the source to the burner, the throttle valve unit having a movable valve member and a valve seat controlled by the valve member, the throttle valve unit having an electrically operated unit operatively associated with the valve member to control the position of the valve member relative to the valve seat so as to control the flame height at the burner, the electrically operated unit comprising a fixed magnet unit and a movable magnet unit each of which is adapted to provide a magnetic field that will react with the other magnetic field, one of the magnet units having an electrical conductor that is adapted to vary the force of its magnetic field in relation to the magnitude of an electrical current passing therethrough whereby the valve member is adapted to be positioned relative to the valve seat in relation to the effect created between the magnetic fields. |
