Patent ID: 6857448
Filing Date: 2005-02-22
Classification: F23K,F23N,Y10T

Abstract:
1. A control apparatus for simultaneously controlling flow rates of a first fluid and a second fluid, the first fluid being a liquid and the second fluid being a gas, the apparatus comprising: a control valve for controlling the flow rate of the first fluid, the control valve being a needle valve; a bleed device for bleeding the second fluid; the needle valve being operatively connected to the bleed device by a control member, whereby as the control valve is opened progressively greater amounts to increase flow of the first fluid, the bleed device is progressively closed to decrease bleeding of the second fluid, and, as the control valve is closed progressively greater amounts to decrease flow of the first fluid, the bleed device is progressively opened to increase bleeding of the second fluid; and a valve body having a cavity therein and a valve member releasably connected to the control member and rotatably received within the cavity, the bleed device being on the valve member, the cavity having a female threaded portion which threadedly receives a male threaded portion of the valve member, whereby rotation of the control member moves the valve member axially within the cavity to open or close the bleed device, the needle valve including a shank having a valve tip, the shank being received by the valve member, the shank being releasably connected to the control member, whereby, when the control member is connected to the valve member and to the shank, rotation of the control member in a first rotational direction moves the valve tip toward a valve seat to close the needle valve and rotation of the control member in a second rotational direction, opposite the first rotational direction, moves the valve tip away from the valve seat to open the needle valve.