Abstract:
A high-speed, high pressure rotary valve is provided comprising a valve body, a valve element which includes a plurality of passageways therethrough that is configured to be rotatably disposed within the valve body, and means for rotating the valve element within the valve body whereby a single rotation of the valve element results in the creation of multiple discrete flow paths through the rotary valve and multiple valve actuation cycles.

Description:
BACKGROUND  
         [0001]    A. Field of Invention  
           [0002]    This invention relates to the field of high pressure, high speed rotary valves. More specifically, this invention comprises a rotary valve with multiple flow paths that is capable of valve actuation cycle frequencies in excess of 2000 Hz at inlet pressures in excess of 600 psi.  
           [0003]    B. Description of Related Art  
           [0004]    Rotary valves are used in industry for a number of applications like controlling the flow of liquids to molds, regulating the flow of hydraulic fluids to control various machine functions, industrial process control, and controlling fluids which are directed against work pieces. The vast majority of these applications are conducted at low fluid pressures and at either low rotational speeds or through an indexed movement. These applications have been addressed through application of various known fluid regulation valve applications including gate valve, ball valves, butterfly valves, rotating shafts with various void designs and configurations, solenoid actuated valves of various designs, and valves designed with disks with multiple holes to redirect flow streams. These applications are generally acceptable for low speed, low pressure processes, but are not suitable for high speed, high pressure processes.  
           [0005]    For example, solenoid valves are effective for regulating fluid flow up to a frequency of approximately 300 Hz at a pressure of up to 200 psi. These limitations are primarily due to the physical design of the solenoid which relies upon the reciprocating motion of magnetic contacts and is therefore subject to significant acceleration and deceleration forces, particularly at higher frequencies. These forces, the resulting jarring action, and the frictional heat generated make these type valves subject to failure at high frequencies of actuation.  
           [0006]    Rotary valves employing multiple outlets have been used at frequencies up to 1000 Hz in applications where a low pressure differential between valve inlet and outlet ports is desired. These valves, however, are large and complex and necessarily have significant physical space requirements for the valve and for the appurtenant inlet and outlet piping.  
           [0007]    Other methods of regulating flow force the fluid to travel through various tortuous paths, changing directions prior to exiting the device. Such a method of turning and returning the flow stream results in time delays in the output stream, significant head loss, and can be quite mechanically complicated.  
           [0008]    Information relevant to attempts to address these problems can be found in U.S. Pat. Nos. 4,986,307, 4,345,228, 5,913,329, 6,269,838, 6,253,778, 5,988,586, 5,787,928, 5,758,689, 5,524,863, 5,305,986, 5,273,072, 5,255,715, 5,048,630, 4,658,859, 4,577,830, 4,231,545, 4,212,321, 4,177,834, 4,113,228, 3,941,351, 3,906,975, 3,774,634, 2,312,941, and 2,749,941. However, each one of these references suffers from one or more of the following disadvantages:  
           [0009]    1. The valve actuation cycle speed (frequency) of the valve is too low;  
           [0010]    2. The valve is large and physically complex;  
           [0011]    3. The valve creates significant head loss;  
           [0012]    4. The valve cannot satisfactorily operate at high inlet pressures; or  
           [0013]    5. The valve cannot create the necessary frequency or amplitude of flow perturbation.  
           [0014]    For the foregoing reasons, there is a need for a high-speed, high pressure rotary valve for controlling the flow of a fluid to produce high frequency fluid pulses or perturbations. Further, there is a need for such a valve which is relatively simple in design, compact in size, compatible with standardized piping systems, and suitable for high pressure applications with minimal head loss through the valve. Such a valve may be used in applications such as creating aerosols of liquids and gases (e.g., carburetion of fuels, pesticide application, paint spraying), fuel injection for engine systems, and as part of active noise cancellation systems for supersonic jet engines and other high energy noise production systems.  
         SUMMARY  
         [0015]    The present invention is directed to a high-speed, high pressure rotary valve that satisfies this need. The rotary valve comprises a valve body having an inlet and an outlet and a valve element rotatably disposed within the valve body. The valve element has a plurality of passageways therethrough, and is free to rotate within the valve body. Means are provided for rotating the valve element such that each complete rotation of the valve element creates a plurality of discrete flow paths through the valve body and the valve element and a plurality of discrete valve actuation cycles.  
           [0016]    Accordingly, several objects and advantages of the present invention are:  
           [0017]    1. Operation at valve actuation cycle frequencies of at least 2000 Hz;  
           [0018]    2. Operation at valve inlet pressures in excess of 600 psi;  
           [0019]    3. Production of high energy flow perturbations;  
           [0020]    4. Production of high sound pressure level sounds at discrete frequencies; and  
           [0021]    5. Small size and simple piping configurations. 
       
    
    
     DRAWINGS  
       [0022]    These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings wherein:  
         [0023]    [0023]FIG. 1 shows an assembly view of the rotary valve  11  of the present invention;  
         [0024]    [0024]FIG. 2 shows an exploded view of the rotary valve  11  of the present invention;  
         [0025]    [0025]FIG. 3 shows an upstream-end view of the main valve body of the rotary valve  11  of the present invention;  
         [0026]    [0026]FIG. 4 shows and a side view of the main valve body of the rotary valve  11  of the present invention;  
         [0027]    [0027]FIG. 5 shows a downstream-end view of the main valve body of the rotary valve  11  of the present invention;  
         [0028]    [0028]FIG. 6 shows a top view of the main valve body of the rotary valve  11  of the present invention;  
         [0029]    [0029]FIG. 7 shows a cross-sectional elevation view, along section line “ 1 - 1 ” of the main valve body of the rotary valve  11  of the present invention;  
         [0030]    [0030]FIG. 8 shows a side view of the downstream valve body of the rotary valve  11  of the present invention;  
         [0031]    [0031]FIG. 9 shows an upstream-end view of the downstream valve body of the rotary valve  11  of the present invention;  
         [0032]    [0032]FIG. 10 shows a cross-sectional view, along section line “ 2 - 2 ” of the downstream valve body of the rotary valve  11  of the present invention;  
         [0033]    [0033]FIG. 11A shows a top view of the valve ball of the rotary valve  11  of the present invention;  
         [0034]    [0034]FIG. 11B shows another top view of the valve ball of the rotary valve  11  of the present invention;  
         [0035]    [0035]FIG. 11C shows a side view of the valve ball of the rotary valve  11  of the present invention;  
         [0036]    [0036]FIG. 11D shows another side view of the valve ball of the rotary valve  11  of the present invention;  
         [0037]    [0037]FIG. 12 shows a cross-sectional view, along section line “AA” of the valve ball of the rotary valve  11  of the present invention;  
         [0038]    [0038]FIG. 13 shows an upstream-end view and a side view of the downstream seat of the rotary valve  11  of the present invention;  
         [0039]    [0039]FIG. 14 shows a cross-sectional view, along section line “ 4 - 4 ” of the downstream seat of the rotary valve  11  of the present invention;  
         [0040]    [0040]FIG. 15 shows an upstream-end view and a side view of the upstream seat of the rotary valve  11  of the present invention;  
         [0041]    [0041]FIG. 16 shows a cross-sectional view, along section line “ 5 - 5 ” of the upstream seat of the rotary valve  11  of the present invention;  
         [0042]    [0042]FIG. 17 shows a top view and a side view of the valve stem of the rotary valve  11  of the present invention;  
         [0043]    [0043]FIG. 18 shows test data of frequency (Hz) versus sound pressure level (dB) at a 500 psi input pressure;  
         [0044]    [0044]FIG. 19 shows test data of time (seconds) versus pressure (psi) at a 500 psi input pressure, with the pressure measurement taken ten diameters downstream of the valve body;  
         [0045]    [0045]FIG. 20 shows test data of frequency (Hz) versus sound pressure level (dB) at a 600 psi input pressure;  
         [0046]    [0046]FIG. 21 shows test data of time (seconds) versus pressure (psi) at a 600 psi input pressure, with the pressure measurement taken ten diameters downstream of the valve body; 
     
    
     DESCRIPTION  
       [0047]    With reference to FIG. 1, a rotary ball valve assembly  11  is shown, and in FIG. 2 the components of the assembly, i.e., the main valve body  21 , the downstream valve body  22 , the downstream valve seat  23 , the upstream seat  24 , the valve ball  25 , and the valve stem  26 , are shown.  
         [0048]    With reference to FIG. 3, the upstream end of main valve body  21  is shown. FIG. 4 shows a side view of the main valve body  21 , FIG. 5 shows an end view of the downstream end of main valve body  21 , FIG. 6 shows a plan view of main valve body  21 , and FIG. 7 shows a cross-sectional view, along section line “ 1 - 1 ” shown in FIG. 3, of main valve body  21 .  
         [0049]    With reference to FIG. 8, a side view of the downstream valve body  22  is shown. FIG. 9 shows an end view of the upstream end of the downstream valve body  22 . FIG. 10 is a cross sectional view, along section line “ 2 - 2 ” shown in FIG. 9, of the downstream valve body  22 .  
         [0050]    [0050]FIG. 11 shows four views of the valve ball  25 . FIG. 11A shows valve ball  25  with three separate flow paths therethrough. As positioned in FIG  11 A, valve ball  25  is in a closed position with respect to flow along a flow path defined by section line “ 3 - 3 .” FIG. 11B shows valve ball  25  in an open position with respect to flow along a flow path defined by section line “ 3 - 3 ” in FIG. 11A. FIG. 11C shows a side view of valve ball  25  corresponding to the top view shown in FIG. 11A, and FIG. 11D shows a side view of valve ball  25  corresponding to the top view shown in FIG. 11B. FIG. 12 shows a cross-sectional view, along section line “ 3 - 3 ” shown in FIG. 11A, of valve ball  25 .  
         [0051]    [0051]FIG. 13 shows a side view and an upstream end view of downstream seat  23 . FIG. 14 shows a cross-sectional view, along section line “ 4 - 4 ” shown in FIG. 13, of downstream seat  23 . FIG. 15 shows a side view and an upstream end view of upstream seat  24 . FIG. 16 shows a cross-sectional view, along section line “ 5 - 5 ” shown in FIG. 15, of upstream seat  24 . FIG. 17 shows a side view and a top view of valve stem  26 .  
         [0052]    [0052]FIG. 18 and FIG. 20 show a plot of frequency (Hz) versus sound pressure level (dB) at a 500 psi (FIG. 18) and a 600 psi inlet pressure (FIG. 20) with air as the test fluid. FIG. 19 and FIG. 21 show a plot of time (seconds) versus pressure (psi) at a 500 psi inlet pressure (FIG. 19) and at a 600 psi inlet pressure (FIG. 20).  
         [0053]    Referring again to FIG. 1 and FIG. 2, one embodiment of a high speed rotary ball valve  11  of the present invention includes a main valve body  21 , an upstream seat  24  which is removably received into the interior cavity  27  of main valve body  21 , a valve ball  25  that rotatably seats in interior cavity  27  in the interior of main valve body  21  between upstream seat  24  and downstream seat  23 . Downstream seat  23  is removably received into interior cavity  27  and the assembly of upstream seat  24 , valve ball  25 , and downstream seat  23  is held in position in interior cavity  27  by downstream valve body  22  which is removably received into main valve body  21 . Valve stem  26  is removably attached to valve ball  25  and extends through cavity  27  and through an opening  28  in main valve body  21 . The portion of valve stem  26  extending vertically from main valve body  21  (as shown in FIG. 1) is available for coupling to a high speed actuator (not shown). Valve stem  26  is sealed using conventional gaskets, packing, rings, or other similar type sealing means.  
         [0054]    The main valve body  21 , the upstream seat  24 , the downstream seat  23 , the valve stem  26 , the valve ball  25 , and the downstream valve body  22  are fabricated from a suitable material, such as a carbon steel, a stainless steel, a ceramic, a ceramet (name used in trade), a carbide alloy, a plastic, or a combination thereof. Materials which resist corrosion and erosion when exposed to the process fluid are preferred.  
         [0055]    The valve ball  25  includes a plurality of cylindrical central passageways  110  which extend horizontally (as viewed in FIG. 1) through the valve ball. The number of passageways is constrained by the diameter of valve ball  25  and the diameter of each passageway.  
         [0056]    The diameter of the valve ball  25  and the cavity  27  are sized so that valve ball  25  is rotatable within the cavity  27  about a vertical axis  13 . Valve ball  25  is supported by upstream seat  24  and downstream seat  23  and is free to rotate within cavity  27 . Both upstream seat  24  and downstream seat  23  are surfaced with a conventional sealing material appropriate for rotation of the valve ball at a high speed such as glass filled PTFE.  
         [0057]    In one embodiment of the valve ball  25 , as shown in FIG. 11A, valve ball  25  has three passageways  110  equally spaced around the circumference of the ball with each passageway  110  intersecting the vertical axis  13 . Passageways  110  are coplanar, of equal diameter, and equally spaced about the circumference of valve ball  25 . Valve ball  25  rotates about a vertical axis  13  that intersects each flow passageway at the center of the ball. As shown in the embodiment depicted in FIG. 11D, valve ball  25  has a slot milled in its top surface for receiving valve stem  26 . As shown in FIG. 2, the diameter of each passageway  110  closely approximates the diameter of the discharge  141  of the downstream seat  23 . It can be seen that, because of the positioning of the passageways  110 , each 360 degree rotation of valve ball  25  results in six valve actuation cycles (a valve actuation cycle is defined as the valve going from a closed to an open position and back to closed). Therefore, in one embodiment of the invention, it is possible to achieve a six to one multiplier effect in that one complete rotation of valve stem  26  results in six valve actuation cycles. It is possible to increase or decrease this multiplier by increasing or decreasing the number of passageways  110  through the valve ball  25 . Thus, a valve actuation cycle frequency of 2400 Hz can be achieved at a valve stem rotational speed of only 400 revolutions per second.  
         [0058]    The multiplier effect is dependent upon the number of passageways through valve ball  25 . For discontinuous flow (meaning the valve cycles between the fully open and the fully closed positions) it is necessary to include a separation between the passageways at least equal to the diameter of the discharge  141 . In this method of operation, the multiplier effect is then limited by the diameter of the valve ball  25 , and the diameter of the passageways through valve ball  25 . Non-discontinuous flow profiles can be obtained by closer spacing of the flow passageways. The profile of the pressure pulse produced by each valve actuation cycle can also be modified by enlarging the entrance and exit of each passageway while maintaining the interior diameter of each passageway. This modification allows flow to begin sooner and end later for each valve actuation cycle.  
         [0059]    [0059]FIG. 18 and FIG. 19 show operation of the valve of the present invention at a valve actuation cycle frequency of approximately 2300 Hz. At this speed, a sound pressure level of approximately 135 dB at a frequency of 2300 Hz is achieved. Similarly, FIG. 20 and FIG. 21 show operation of the valve of the present invention at a valve actuation cycle frequency of approximately 2200 Hz. At this speed, a sound pressure level of approximately 135 dB at a frequency of 2200 Hz is achieved. As can be seen, it is possible to produce high energy sound pressure levels at the same frequency as the valve actuation cycle frequency. Thus, by controlling valve actuation frequency, the resulting sound frequency can also be controlled. Any high-speed rotary actuator can be used to couple to valve stem  26  and provide rotary motion to valve ball  25 .  
         [0060]    In operation, a high pressure fluid such as, for example, air, steam, or a liquid, is supplied to the main valve body inlet  29 . As valve ball  25  rotates, valve actuation cycles occur and, as shown in FIG. 18 through FIG. 21, downstream pressure pulses or perturbations are produced along with a sound pressure characterized by a characteristic frequency equal to the valve actuation cycle frequency.  
         [0061]    Advantages  
         [0062]    The previously described versions of the invention have many advantages including valve actuation cycle frequencies of over 2000 Hz, small valve sizes and simple valve construction, valve operation at inlet pressures of at least 600 psi, production of high amplitude flow perturbations, low head loss through the valve, simple piping connection design, and the production of high-energy sound at controllable frequencies.  
         [0063]    Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. For example, the valve body may be composed of any other structure material capable of retaining valve ball  25  for rotational movement while also being capable of disassembly to allow maintenance, removal, and replacement of interior components of the valve assembly. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein.