Throttle valve

A valve body is enlarged to contain the area of throttling vanes which are mounted on actuating shafts; the body is tapered along with the vanes to provide a loss of body area which is uniform to the throat section of the valve body; regulation of the vanes is accomplished by the shafts which extend outwardly of the valve body.

BACKGROUND OF THE INVENTION 
The control of fluids have in the past been usually accomplished with 
standard ball, butterfly, globe needle or plug valves. In effecting such 
fluid control, the control valves cause turbulence, cavitation, erosion, 
vibration and noise under certain regulating conditions. Present 
environmental considerations require noiseless regulation and with little 
or no cavitation effect. To meet the requirements, special valves, such as 
those with stacked plates, have been proposed but these are extremely 
costly. 
A general object of the present invention is to provide a fluid flow 
regulatory valve which is simple in construction and positive in 
operation. 
Still another object of the present invention is to provide fluid flow 
regulatory valve utilizing the venturi principle. 
Yet another object of the present invention is to provide adjustable 
regulators within a valve to regulate the fluid flow therethrough. 
A further object of the present invention is to provide a regulatory valve 
following the venturi principle of controlled flow path causing any 
cavitation bubbles to implode harmlessly in the flow stream. 
A still further object of the present invention is to provide a fluid flow 
control valve having a hydraulic shape which drastically reduces the 
potential for cavitation thereby reducing the potential for metal removal. 
SUMMARY OF THE INVENTION 
The body of the valve is enlarged to contain the area of the control vanes 
which are selectively positionable by means of a drive shaft. The body is 
tapered along the vanes to provide a loss of body area which is uniform to 
the throat section. An increase in body area is effected from the throat 
section which may either be within the valve body or as an added pipeline 
section. The control vanes are configured to fit the contour of the 
internal body cavity. The tapered portion of the valve body may be varied 
by in angular reduction according to control requirements. The vane drive 
shaft is supported in trunnion bearings and shaft seals are provided to 
prevent leakage. Also, the joint space between the ends of the vanes 
adjacent the interior surface of the valve body are also provided with 
seals to prevent material leakage around the vanes.

DESCRIPTION OF THE INVENTION 
In the drawings the reference number 10 indicates the valve of the present 
invention. The valve includes a cylindrical body 12 having an enlarged 
flanged inlet 14. The body 12 is reduced in diameter from the inlet 14 as 
at 16 to provide a loss in body area to provide a throat section 17. From 
the throat section 17, the valve body area is increased as at 18. The end 
of the increased body portion 18 is provided with a flange 19 and the 
opening therein constitutes the outlet of the valve. 
Within the reduced portion 16 of the valve body there is provided a pair of 
control vanes 22 and 23. The vanes 22 and 23 are best described as being 
similar in configuration to one-half of a mollusk shell. Each of the vanes 
22 and 23 conform to the interior wall surface configuration exhibiting a 
similar tapered configuration conforming to the taper of the interior of 
the valve body and in the same direction. As shown, each vane 22 and 23 
has the center portion of its free end relieved as at 26 and 27, 
respectively. Thus, with the vanes 22 and 23 in a closed position, the 
relieved portions 26 and 27 of the vanes cooperate to define a restricted 
fluid flow opening 31 to permit a predetermined minimum of controlled flow 
through the valve. The provision of the minimum opening 31 with the vanes 
closed ensures that high velocity of the fluid is not experienced, thus 
preventing erosion and cavitation potential. The size of the opening 31 is 
preferred to be within 5 percent of the maximum area of the throat section 
17. 
The vanes are dimensioned so that in a closed position the vane 23 fits 
fairly close within the vane 22 as depicted in FIG. 4. This prevents 
excessive fluid leakage through the lips of the vanes. 
The vanes 22 and 23 are each positionable and are arranged to move 
simultaneously and at the same rate. To this end, a drive shaft 32 is 
provided and is drivenly engaged in a boss 33 formed on the inner end of 
the vane 22. The shaft is journalled in bosses 36 and 37 of a housing 38 
formed in the valve body 12. Shaft seals are provided to prevent leakage. 
A similar arrangement is provided for the vane 23 wherein a shaft 41 
extends through and is drivenly engaged in a boss 42 formed on the end of 
the vane 23. The shaft 41 is journalled in bosses 43 and 44 of a housing 
46 formed in the valve body 12. 
For the purpose of effecting simultaneous movement of the vanes 22 and 23, 
there is provided a cross shaft 51, as shown in FIG. 1. The ends of the 
cross shaft 51 are engaged in worm gear drive boxes 52 and 53 which 
operate to transfer the rotary drive of shaft 51 to the shafts 32 and 41 
in a well known manner. Drive input to the shaft 51 is accomplished by 
means of an actuator 56, the output shaft (not shown) extends into the 
gear box 52 and is drivenly connected to the shaft 51. The actuator 56 
herein shown is manually operable; however, it will be appreciated that a 
power operated actuator can be employed to good advantage. In utilizing a 
power actuator, a control signal will be utilized to operate the actuator 
rather than the manual control wheel 57 associated with the manual 
actuator 56. 
By varying the angular position of the vanes 22 and 23, the flow of fluid 
through the valve is varied and the fluid follows the contour of the 
vanes. This control as exercised by the vanes on the fluid provides a wide 
range of control with no harmful cavitation.