Patent Abstract:
A controlled-clearance sealing compressor device that provides precision rotor centering directly with respect to the stator housing, vane centering with respect to rotor (not the stator) and the dynamic balance design of the gliders required for practical single and dual vane devices. The devices uses roller bearings to control the radial position of the vane and control rods or pins are used to control axial positioning of the vane, its ‘centralization’ with respect to the rotor and the endplates. The positive displacement rotary vane compressors and vacuum pumps have friction reduction, efficiency enhancement and exceedingly long operating life as a result of the non-contact gas sealing of the process gas within the rotary vane compressors and vacuum pumps. In an embodiment the positive displacement compressing device is used in transportation vehicles.

Full Description:
This is a Divisional of Application of Ser. No. 11/219,481 filed on Sep. 2, 2005, now U.S. Pat. No. 7,740,460 titled “Controlled-Clearance Sealing Compressor Devices” which is a continuation-in-part of U.S. patent application Ser. No. 11/198,773 filed on Aug. 5, 2005 titles: “Reversible Valving Systems for Use in Pumps and Compressing Devices ” now U.S. Pat. No. 7,491,037. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to positive displacement rotary vane compressors and vacuum pumps and, in particular, to methods, systems, apparatus and devices that provide a mechanically-governed, positive-displacement, non-contact sealing compression or vacuum device that uses roller bearings to control the radial position of the vane and uses control rods or pins to control the axial position of the vane with respect to the rotor and the endplates. 
     BACKGROUND AND PRIOR ART 
     U.S. Pat. No. 5,087,183, issued on Feb. 11, 1992 to Edwards, the applicant of the present patent application, and entitled “Rotary Vane Machine with Simplified Anti-Friction Positive Bi-Axial Vane Motion Control” discloses a means for constraining, in a precision fashion, the circumferential motion of the vane so that the tip of the vane does not engage the inner bore of the stator housing, but is close enough to provide adequate gas sealing. Machines produced according to the &#39;183 patent have significantly less friction than conventional contact vane machines. The Edwards &#39;183 patent also discloses the use of roller bearings as the anti-friction element and includes use of one, two or three vanes. 
     Vane centering (attaining accurate axial positioning to avoid side contact between the vane ends and the stator endplates) is easily achieved through the use of ball bearings as taught, for example, in U.S. Pat. No. 5,374,172, issued on Dec. 20, 1994 to Edwards, and entitled “Rotary UniVane Gas Compressor.” Further, axially positioning through the use ball bearings is commonly used in both alternating and direct current electric motors as well as in contact-sealing vane compressors. Also made of record is U.S. Pat. No. 5,160,252 issued on Nov. 3, 1992 which is a continuation-in-part of the &#39;183 patent. 
     In prior art multiple vane machines, the radial and tangential velocities of the vanes are constantly varying with respect to one another and, thus require the use of special segmented bearings that allow each vane to vary in speed independent of the other vanes. U.S. Pat. No. 5,374,172 issued on Dec. 20, 1994 to Edwards, discloses a single rotating vane machine. Unlike multi-vane machines of the prior art at the time, conventional dual race bearings are used to control the radial non-contact location of the single vane. Additionally, means are provided for dynamically balancing the rotating rotor and vane. Machines produced according to the &#39;172 patent are characterized by having very low mechanical friction and excellent gas sealing, and are hence, very energy efficient. 
     U.S. Pat. No. 6,503,071 issued on Jan. 7, 2003 to Edwards, discloses a high-speed UniVane® fluid-handling device. This single vane gas displacement apparatus comprises a stator housing with a right cylindrical bore enclosing an eccentrically mounted rotor which also has a radial slot in which is movably radially positioned a single vane. The vane is tethered to antifriction vane guide assemblies concentric with the housing bore. Then vane has a pre-selected center of gravity located proximate to the housing bore axis. An option is to have a port in the vane for ducting high-pressure gas to the inlet side to react against the rotor slot to reduce vane contact therewith. 
     U.S. Pat. No. 6,623,261 issued on Sep. 23, 2003, also to Edwards, discloses a single-degree-of-freedom controlled-clearance UniVane® fluid-handling machine. In this patent, the rotor has a rotational axis and carries at least one vane which is supported by a vane guide apparatus for rotation about a stator axis which is spaced from the rotor axis a preselected amount and where both the rotor and vane have axial flat surfaces which are rotated adjacent to stationary flat surfaces of a stator or stator endplates. The patent discloses a provision for axial adjustment of the vane with respect to the flat surface of the stator endplates and independently provides an adjustment of the rotor end surfaces with respect to the stator end surfaces. 
     The single vane and double vane apparatus of the present invention embody two important distinctions from the prior art UniVane® patents (U.S. Pat. Nos. 5,374,172, 6,503,071, 6,623,261). First, roller bearings are used to control the radial position of the vane and second, axial positioning control rods or pins are used to dictate the axial position of the vane (its ‘centralization’) with respect to the rotor and the endplates. The prior art UniVane patents teach the use of a second set of ball bearings that simultaneously control both the radial and axial location of the vane and operate with respect to the stator endplates and not the rotor. 
     Unlike the prior art, the present invention teaches specific means to achieve the practical use of both a single vane and a dual vane device in which problems of dynamic balance and precision radial vane centering is achieved through the use of roller bearings; not ball bearings. The embodiments taught herein primarily encompass the application of precision rotor centering directly with respect to the stator housing, vane centering with respect to rotor (not the stator) and the dynamic balance design of the gliders required for practical single and dual vane devices. 
     SUMMARY OF THE INVENTION 
     A primary objective of the invention is to provide new methods, systems, apparatus and devices that provide a mechanically-governed, positive-displacement, non-contact sealing compression or vacuum device. 
     A second objective of the invention is to provide new methods, systems, apparatus and devices to provide a positive displacement rotary vane compressors and vacuum pumps that embrace the basic concept of friction reduction, and efficiency enhancement and exceedingly long operating life through the creation of specific means that result in non-contact gas sealing of the process gas. 
     A third objective of the invention is to provide new methods, systems, apparatus and devices that provide a mechanism whose moving parts exercise precision repetitive internal motion at a level of accuracy required to insure that the moving parts do not contact the static, non-moving parts of the machine and, simultaneously, maintain internal sealing clearance gaps small enough to keep internal leakage acceptably small in order to yield high efficiency. 
     A fourth objective of the invention is to provide new methods, systems, apparatus and devices to provide precision rotor centering directly with respect to the stator housing, vane centering with respect to rotor (not the stator) and the dynamic balance design of the gliders required for practical single and dual vane devices. 
     A fifth objective of the invention is to provide new methods, systems, apparatus and devices that uses roller bearings to control the radial position of the vane. 
     A sixth objective of the invention is to provide new methods, systems, apparatus and devices that uses axial positioning control rods or pins to control the axial position of the vane, its centralization, with respect to the rotor and the endplates. 
     A seventh objective of the present invention is to provide new methods, systems, apparatus and devices for a DuoVane machine wherein the second vane blocks the noise pulse inherent to the incomplete emptying of the volume at the discharge valve assembly in the MonoVane unit to provide both a quieter and considerably smaller machine. 
     An eighth objective of the present invention is to provide new methods, systems, apparatus and devices for a positive-displacement, non-contact sealing compression device for circulating hydrogen, ionized or deionized water and hydrogen or an alternative fuel. 
     A ninth objective of the present invention is to provide new methods, systems, apparatus and devices for a positive-displacement, non-contact sealing compression device for fuel cell applications for use with transportation devices, such as cars, trucks, busses and the like. 
     A tenth objective of the present invention is to provide new methods, systems, apparatus and devices for high efficiency, low-pressure, non-lubricated air compressors and hydrogen circulators. 
     An eleventh objective of the present invention is to provide new methods, systems, apparatus and devices to provide a compressor for use in life sciences, semiconductor processing, medical device, vacuum pump applications, and for pond aeration systems at golf courses. 
     A twelfth objective of the present invention is to provide new methods, systems, apparatus and devices to provide a compressor for use as a reversible refrigerant compressors, and miniature compressors and vacuum pumps. 
     A thirteenth objective of the present invention is to provide new methods, systems, apparatus and devices to provide a compressor or vacuum device that is lubricant-free. 
     A fourteenth objective of the present invention is to provide new methods, systems, apparatus and devices to provide compressor or vacuum devices that are non-contact and virtually frictionless. 
     The methods, systems, apparatus and devices of the present invention provide a positive displacement apparatus having a stator housing having an interior bore therethrough, a first and a second endplate connected to the stator housing at each end of the interior bore to form a compression or vacuum chamber. A rotor having a rotor shaft is positioned in the interior bore such that one end of the rotor shaft is connected to an external power source for rotating the rotor within the interior bore. A rotor centering device is used for centering the rotor with respect to the stator housing to prevent the rotating rotor from contacting the interior bore and the first and second endplates. A rotating vane assembly having at least one vane and a vane centering device for connecting the rotating vane assembly to the rotor shaft and centering at least one vane with respect to the rotor. The rotor centering device controls a radial position of the rotating vane assembly and the vane centering device controls an axial position of rotating vane assembly to prevent contact of the at least one vane with the stationary compression chamber components. 
     In an embodiment, rotating vane assembly includes one vane. In another embodiment, the vane assembly includes a first and a second vane positioned approximately 180° apart, such that as the first vane and the second vane rotate the second vane blocks a noise pulse inherent to the incomplete emptying of the volume at the discharge valve assembly to provide a quieter compression apparatus. 
     Summarily, the embodiments taught in the present invention described herein primarily encompass the application of precision rotor centering directly with respect to the stator housing, vane centering with respect to rotor (not the stator) and the dynamic balance design of the gliders required for practical single and dual vane devices. 
     Further objects and advantages of this invention will be apparent from the following detailed description of preferred embodiments which are illustrated schematically in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIGS. 1   a  and  1   b  are a front view and a side view, respectively, of an orbital MonoVane device according to the present invention. 
         FIGS. 2   a  and  2   b  shows a disassembled front view and side view, respectively, of the orbital MonoVane device shown in  FIGS. 1   a  and  1   b , respectively. 
         FIGS. 3   a  and  3   b  are a side view and corresponding front view, respectively, showing the use of roller bearings to control the radial location of the vane with respect to a rotor centered with respect to the stator and the use of a centering control rod to control the vane&#39;s axial location. 
         FIG. 3   c  is an expanded view showing the use of roller bearings to control the radial location of the vane with respect to a rotor centered with respect to the stator and the use of a centering control rod to control the vane&#39;s axial location in separated views. 
         FIGS. 4   a ,  4   b  and  4   c  show alternative examples of the vane-centralizing positional control rod and the mating passage accommodating the control rod. 
         FIG. 5   a  shows front view of the DuoVane embodiments of the present invention wherein the roller bearings are placed on the OD of the glider rings. 
         FIG. 5   b  shows a side view of the DuoVane embodiment shown in  FIG. 5   a.    
         FIGS. 6   a  and  6   b  show expanded front and side views, respectively, of the DuoVane apparatus shown in  FIGS. 5   a  and  5   b , respectively, showing additional detail. 
         FIG. 7   a  is a front view showing another example of the DuoVane apparatus. 
         FIG. 7   b  is a side view of the DuoVane machine shown in  FIG. 7   a.    
         FIG. 8   a  is a front view showing additional detail of the rotating components of the DuoVane assembly shown in  FIG. 7   b.    
         FIGS. 8   b  and  8   c  show a front view of the rotating vane assembly and the vane counter balance, respectively, from one side. 
         FIGS. 8   d  and  8   e  show a front view of the rotating vane assembly and the vane counter balance, respectively, from an opposite side. 
         FIG. 9  shows another example of the DuoVane apparatus embodiment shown in  FIG. 8 . 
         FIG. 10   a  shows yet another example of the DuoVane apparatus embodiment shown in  FIG. 5   a  through  FIG. 9 . 
         FIGS. 10   b  and  10   c  show a front view of the rotating vane assembly and the vane counter balance, respectively, shown in  FIG. 10   a  from one side. 
         FIGS. 10   d  and  10   e  show a front view of the rotating vane assembly and the vane counter balance, respectively, shown in  FIG. 10   a  from an opposite side. 
         FIG. 11  shows yet another example of the DuoVane apparatus embodiment shown in  FIG. 5   a  through  FIG. 9 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its application to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation. 
     The following is a list of the reference numbers used in the drawings and the detailed specification to identify components: 
     
       
         
               
               
               
             
           
               
                   
                   
               
             
             
               
                   
                  5 
                 inlet manifold 
               
               
                   
                  10 
                 left endplate 
               
               
                   
                  15 
                 discharge manifold 
               
               
                   
                  20 
                 stator 
               
               
                   
                  30 
                 right endplate 
               
               
                   
                  40 
                 rotor 
               
               
                   
                  42 
                 void region 
               
               
                   
                  44 
                 rotor slot 
               
               
                   
                  50 
                 vane 
               
               
                   
                  52 
                 axle through-hole 
               
               
                   
                  54 
                 vane slot 
               
               
                   
                  56 
                 vane hole 
               
               
                   
                  56a 
                 vane hole 
               
               
                   
                  57 
                 vane hole 
               
               
                   
                  60 
                 roller bearing 
               
               
                   
                  62 
                 glider races 
               
               
                   
                  64 
                 counterbalance voids 
               
               
                   
                  70 
                 vane axle 
               
               
                   
                  72 
                 cross-hole 
               
               
                   
                  82 
                 vane ring spacer 
               
               
                   
                  80 
                 glider race post 
               
               
                   
                  90 
                 control rod 
               
               
                   
                  91 
                 control rod 
               
               
                   
                 100 
                 rotor shaft 
               
               
                   
                 103 
                 hole 
               
               
                   
                 104 
                 shaft hole 
               
               
                   
                 110 
                 ball bearing 
               
               
                   
                 140 
                 rotor 
               
               
                   
                 144 
                 first rotor slot 
               
               
                   
                 145 
                 second rotor slot 
               
               
                   
                 150 
                 first vane 
               
               
                   
                 151 
                 second vane 
               
               
                   
                 152 
                 axle through hole 
               
               
                   
                 153 
                 axle through hole 
               
               
                   
                 156 
                 vane hole 
               
               
                   
                 157 
                 vane hole 
               
               
                   
                 161 
                 roller bearings 
               
               
                   
                 162 
                 first glider race 
               
               
                   
                 163 
                 second glider race 
               
               
                   
                 170 
                 discharge valve assembly 
               
               
                   
                 180 
                 vane axle 
               
               
                   
                 181 
                 vane axle 
               
               
                   
                 190 
                 control rod 
               
               
                   
                 191 
                 centering rod 
               
               
                   
                 240 
                 rotor 
               
               
                   
                 250 
                 vane 
               
               
                   
                 251 
                 vane 
               
               
                   
                 257 
                 centering rod 
               
               
                   
                 261 
                 bearings 
               
               
                   
                 262 
                 glider racers 
               
               
                   
                 263 
                 glider racers 
               
               
                   
                 265 
                 bearing mount 
               
               
                   
                 270 
                 vane axle stub 
               
               
                   
                 270a 
                 snap ring 
               
               
                   
                 271 
                 vane axle stub 
               
               
                   
                 271a 
                 snap ring 
               
               
                   
                 275 
                 vane axle pass-through void 
               
               
                   
                 276 
                 hot dog-shaped voids 
               
               
                   
                 277 
                 voids 
               
               
                   
                 280 
                 vane bearing rings 
               
               
                   
                 282 
                 balance voids 
               
               
                   
                 285 
                 vane 
               
               
                   
                 286 
                 endplate 
               
               
                   
                 286a 
                 extension 
               
               
                   
                 287 
                 cross slots 
               
               
                   
                 290 
                 axle stubs 
               
               
                   
                   
               
             
          
         
       
     
     The methods, systems, apparatus and devices of the present invention provide very exact mechanical devices that rigidly holds rotating compressor parts in precision cyclic paths of continuous motion that do not engage or touch the non-rotating components. The non-engagement distance, the leakage clearance is small enough to insure that the gas being processed by the compressor has only minimal leakage during inlet, compression and discharge. In the preferred embodiment of the present invention, the rotating rotor and its accompanying vane or vanes are positioned securely within their non-rotating stator such that they do not rub against the inner surfaces of this stationary cavity which includes both opposing endplates and the interior bore of the stator housing. 
     The present invention provides two new non-contact sealing compressors and variations thereof herein after called MonoVane for the single-vane version and DuoVane for the dual-vane version. Certain embodiments are less expensive to manufacture and operate at much higher pressures, including refrigerant compressor pressures with the use of a lubricant. 
     Both the MonoVane and DuoVane embodiments use roller bearings to control the radial position of the vane and use control rods or pins to control axial positioning of the vane, its ‘centralization’ with respect to the rotor and the endplates. The prior art devices used a second set of ball bearings to simultaneously control both the radial and axial location of the vane and operated with respect to the stator endplates and not the rotor. 
     This centering of the rotating part is achieved because ball bearings hold both radial and axial positioning. On the other hand, roller bearings, while capable of withstanding very significant loads and are generally much less expensive than ball bearings, only position radially, they have no significant capability of constraining items in the axial direction. 
     In compressing and vacuum devices it is very important to insure that the vane, as well as the rotor, does not rub against either of the stator endplates. The present invention provides mechanisms and structures that accommodate the requirement of precise radial vane positioning with the use of roller bearings that do not provide axial position control. 
     A method for determining the structural requirements to provide apparatus and devices according to the present invention includes the following steps. First, the rotor is accurately located with respect to the stator. Having the rotor location determined, the vane is precisely located with respect to the rotor, and not the stator. The accurate axial vane location with respect to the rotor, and therefore the stator, is achieved using control rods that are firmly and accurately installed within the vane slot and rotor shaft to engage a precision hole in the vane to hold the vane in the desired axial position. 
     There is no essential difference in the action of the DuoVane machine and the MonoVane except that by using two vanes the displacement is essentially doubled and the second vane blocks the noise pulse inherent to the incomplete emptying of the volume at the discharge valve assembly in a single-vane unit. Thus, the additional complication involved in the DuoVane does offer both a quieter and considerably smaller machine. 
     Both the MonoVane and the DuoVane operate in essentially the same manner. Specifically, when the rotor shaft  100  is rotated from an external mechanical/electrical power source, air is induced into the compressor through the inlet manifold  5 , is compressed in the volume of the compression chamber created by the outer diameter of the rotor  40 , the internal bore of stator housing  20 , the vane  50  and the sealing and confinement actions of endplates  10  and  30 . 
     When the compression pressure slightly exceeds the pressure within the discharge manifold  15 , the discharge valve assembly opens and permits the pressurized fluid to pass through the compressor and flow through the outlet manifold  15  and flows to its particular objective as dictated by a given application or use. Thus, the compressor simply pulls the gas (often, air) into itself, compresses the gas and expels it. 
     The MonoVane and DuoVane devices are non-contact and virtually frictionless machines that can be applied to many application and the operating parameters may be adjusted to meet the needs of the particular application. For example, according to the present invention the MonoVane and DuoVane devices may be configured for alternative flow rates, inlet pressures, boost pressures and gas density based on the application in which the device is used. More specifically, the device may be configured for a flow rate that is within a range of approximately 20 LPM up to approximately 5000 LPM. Correspondingly, the devices may be configured for an inlet pressure within a range of approximately 0 to approximately 35,000 kPa and a boost pressure of approximately 0 to approximately 250 kPa. 
     One example of an application is for fuel cell applications for use with transportation devices, such as cars, trucks, busses and the like. The devices can be used for circulating hydrogen, ionized or deionized water and hydrogen or an alternative fuel. Other uses include high efficiency, low-pressure, non-lubricated air compressors and hydrogen circulators, compressor for use in life sciences, semiconductor processing, medical device, vacuum pump applications, for pond aeration systems at golf courses, reversible refrigerant compressors, and miniature compressors and vacuum pumps. While a variety of application has been provided, those skilled in the art will appreciate that the devices of the present invention may be used for alternative applications. 
     First Embodiment—MonoVane 
       FIGS. 1   a  and  1   b  are a front view and a side view, respectively, of the Orbital MonoVane mechanism of the present invention. As shown, the MonoVane device uses a combination of roller bearings to govern the radial vane tip position and an axial positioning element embedded in the rotor and rotor shaft and operating in concert with a mating precision radial hole in the vane to use the rotor for centering the vane. The ball bearings also centralize the rotor location within the stator.  FIGS. 2   a  and  2   b  show the separated layout of the assembly shown in  FIGS. 1   a  and  1   b  and, therefore, further illustrates the details of this invention embodiment. 
     Referring to  FIGS. 3   a  and  3   b  in conjunction with  FIGS. 1   a ,  1   b  and  FIGS. 2   a  and  2   b , the device consists principally of left endplate  10 , stator  20 , right endplate  30 , rotor  40 , and vane  50 . In the configurations shown, rotor shaft  100  is firmly attached to the rotor body  40  by any means known to the art. Rotor rotation occurs when sufficient power is applied to the rotor shaft  100 , which is held and positioned by bearings  110 . As a direct result, the vane  50 , contained within the rotor slot  44 , is propelled in circular motion by the rotor  40  within the stator  20  cavity. The rotor  40  can be confined to its radial and axial position by, in addition to ball bearings  110 , a variety of other conventional bearings such as tapered roller bearings, combinations of roller bearings for the radial location of the rotor shaft  100  and roller thrust bearings for the rotor&#39;s axial location with respect to the stator  20 , as well as roller bearing/ball thrust bearing combinations. 
     In order to enable the machine to become nearly frictionless, however, in addition to insuring that the rotor  40  does not touch either left endplate  10  or right endplate  30  or the stator  20  through rotor centering, other subcomponents are required to insure that the vane  50  does not rub against the stationary parts (i.e.: the stator bore and the inner surfaces of the endplates). Vane axle  70  engages the axle through-hole  52  in vane  50 . The ends of these axles are fastened in usual ways to the inner glider races  62  that operate within the roller bearings  60  (drawn-cup caged type shown here) installed within left and right endplates  10  and  30 , respectively. The circular outer diameter of glider races  62  can be slightly crowned to accommodate slight misalignments of the bearings  60  and glider races  62 . The rollers of roller bearings  60  can also be crowned to accommodate the same conditions. 
     Vane ring spacer  82  provides additional mass to help counter-balance the mass of the vane  50  and vane axle  70 . Counterbalance voids  64  are shaped holes placed in glider races  62  and are sized such that they insure that the rotating vane assembly is dynamically balanced about its center of rotation. Other means known to the art of dynamic balancing can be applied to balance the rotating vane subassembly. This subassembly, again consisting of the vane  50 , vane axle  70  both glider races  62  and the spacer  82 , controls the precise radial location of the vane tip, whose radius is coincident with the center of the vane axle  70 . 
     While roller bearings can take high loads, they lack the ability to control axial vane drift, a back-and-forth motion that would cause wear and friction of the vane sides against the endplates. The present invention overcomes that problem through the use of a centralizing or positioning control rod  90  that is firmly attached to rotor shaft  100  as shown in  FIGS. 1 and 2 , inserted into a hole  103  that is placed in the rotor shaft  100  in the middle of the rotor slot  44  of rotor  40 . 
     In the preferred embodiment, this control rod  90  precisely engages vane hole  56  of vane  50  and prevents axial, side-to-side motion of the vane  50  in rotor slot  44  of rotor  40 . Vane axle  70  is fitted with cross-hole  72  that is large enough to accommodate both the diameter and shape of the control rod  90  and approximately +/− 15° relative angular motion between the vane  50 , control rod  90  and its respective vane axle  70 . While a single control rod  90  is shown, numerous other means can be substituted, such as multiple-rods or conjugate surfaces between the rotor  40  and the vane  50  that will serve to axially anchor the vane to the rotor  40 . 
       FIGS. 3   a  and  3   b  shows a side view and a front view, respectively, of the MonoVane device and  FIG. 3   c  is a disassembled side view of the device shown in  FIGS. 3   a  and  3   b .  FIGS. 3   a ,  3   b  and  3   c  show the use of roller bearings  60  to control the radial location of the vane  50  with respect to the rotor  40  which is centered with respect to the stator  20  and shows the use of a centering control rod  90  to control the vane&#39;s  50  axial location. The rotor  40  is fixed with respect to the stator housing  20  as previously described. However, the centering control rod  91  is fixed in the vane  50  and reciprocates within a precision radial hole  104  within the rotor slot  44  bottom and the rotor shaft  100 . 
     As shown in  FIGS. 3   a  and  3   b , the inverse variant of the control rod method is show wherein an alternative control rod  91  is fixed to the vane  50  within vane hole  57  and reciprocates within shaft hole  104  that passes through the bottom of the vane slot  54 , through the rotor shaft  100  and into the void region  42 . This void  42  is shaped so it can both dynamically balance the rotor  40  to make up for the void  42  comprising the vane slot  44  ( FIG. 2 ) and to accommodate the relative motion of the glider race post  80  and vane axle  70  ( FIG. 1 ). 
       FIGS. 4   a  and  4   b  shows alternative embodiments of the vane-centralizing positional control rod and the mating passage accommodating the control rod  90  and alternatively, control rod  90 . In the example shown in  FIG. 4   a , the control rod  90  has flattened sides wherein the flat sides reduce the positioning accuracy requirement of the location of control rod  90  and disallow inadvertent pressure build-up within the vane hole  56 . This example relieves undesired forces that may arise as slight tolerance stack-ups occur between the vane hole  56 , the vane  40  and the vane slot  44 . 
       FIG. 4   b  shows a round control rod  90  used with a round hole  56  in the vane  50 .  FIG. 4   c  shows that a round control rod  90  could be used within a hole  56   a  that is ‘race track’ in shape and orthogonal to the vane slot  54  to avoid stack-up of tolerances that could lead to contact friction between the control rod  92  and the hole  56   a  and the vane  50  within the vane slot  54 . Recall that there is virtually no axial forces for the control rod  90  to control due to the nearly exact axial symmetry of the compressor and, therefore, the side-to-side fluid forces acting on the vane  50  are very approximately zero, but are strong enough to cause an axial drift and contact with the endplates, resulting in friction and wear if they are not positively held in the correct central axial location. Control rod  90  or alternative control rod  99 , can be hollow ( FIG. 4   c ) and be fitted with cross-holes which can be used both to relieve pressure build-up at the tips of control rods  90  ( FIG. 4   b ) and  91  ( FIG. 4   a ) and to distribute lubricant when used with lubricated machines. 
     As previously described,  FIGS. 1 and 2  show the rotor shaft  100  held in place using ball bearings  110 . In the preferred embodiment, rotor centralization requires that several dimensional conditions be met. In addition to insuring that parts are produced with acceptable precision regarding rotor concentricity, outside diameter and orthogonality of the opposing rotor faces with respect to the bearing surfaces of the rotor shaft. It is important that acceptable tolerances be reached. Further, there is the need for adequate assembled parallelism of the inner surfaces of the endplates, alignment of the rotor bearing bores and a sufficient decrimental difference between the rotor and vane length and the inner span between the endplates, ie: the physical clearance. 
     After satisfying the manufacturing accuracy requirements, the challenge becomes the specific axial location of the bearings such that their position insures centrality of the rotor. This requirement is achieved in a variety of ways, the most obvious of which involves particularly tight manufacturing tolerances so that the rotor will be in the proper place immediately upon assembly. Less accurate machining would add a requirement for the measurement and placement of selective spacers or alternative compensation components. Regardless of the manufacturing method, in the preferred embodiment, the proper placements of the bearings, and, consequentially, the rotor is a primary key to non-contact sealing in the devices of the present invention. 
     Second Embodiment—DuoVane Device 
     The DuoVane machine is a two-vane version of the MonoVane machine described above. Briefly, it contains a second similar, but not identical, set of subcomponents that enable it to carry the second vane in essentially the same way as the MonoVane machine carries the single vane. An example of a DuoVane machine shown in  FIGS. 5 and 6  consists principally of left endplate  10 , stator  20 , right endplate  30 , rotor  140 , and vanes  150  and  151 . In the configurations shown, rotor shaft  100  is firmly attached to the rotor body  140  by any means known to the art. Rotor rotation occurs when sufficient power is applied to the rotor shaft  100 , which is held and positioned by bearings  161 . As a direct result, the vanes  150  and  151 , contained within the rotor slots  144  and  145 , respectively, are propelled in circular motion by the rotor  140  within the stator  20  cavity. 
     Referring to  FIGS. 5   a  and  5   b  and  FIGS. 6   a  and  6   b , as previously described in regard to the MonoVane device, other subcomponents are required to insure that the vanes  150  and  151  do not rub against the stationary parts (i.e.: the stator bore and the inner surfaces of the endplates). Vane axles  180  and  181  engage the axle through-hole  152  and  153  in vanes  150  and  151 , respectively. The ends of these axles are fastened in usual ways to the inner glider races  162  and  163  that operate within the roller bearings  161  (drawn-cup caged type shown here) installed within left and right endplates  10  and  30 , respectively. The circular outer diameter of glider races can be slightly crowned to accommodate slight misalignments of the bearings  161  and glider races  162  and  163 . The rollers of roller bearings  161  can also be crowned to accommodate the same conditions. In the preferred embodiment, this control rod  190  precisely engage vane holes  156  and  157  of vanes  150  and  151 , respectively, and prevents axial, side-to-side motion of the vanes  150  and  151  in rotor slots  144  and  145 , respectively, of rotor  140 . 
     As shown in  FIG. 5   a , addition of the second vane  151  allows nearly twice the displacement of a machine using a single vane, regardless of the type. Further, with the inclusion of a second vane  151 , there is always a vane closing at the inlet port  5  slightly before the discharge port is reached by the leading vane  150 . This is a very important feature from the standpoint of noise containment because as the leading vane  150  passes the discharge port  15 , there is a small volume of high pressure gas that produces a noise pulse of un-expelled gas that travels back around to the outlet port. With one vane  50 , the noise is able to flow out the inlet port  5  and be clearly heard. In the two vane machine, the second vane  151  closes the inlet port  5  before the leading vane  150  reaches the outlet port  15 . The second vane  151  blocks the inherent noise pulse from reaching the environment and recovers the small previously not-discharged mass. This results in a much quieter and slightly more volumetric-efficient compressor. 
       FIGS. 5 through 9  show alternative embodiments of the DuoVane machine. For example,  FIGS. 5 and 6  show the use of a two-piece centering rod  191  with glider races  162  and  163  that run inside the roller bearings  161 . Although a single control is shown, because of dimensional tolerances arising between the opposing vane slots during manufacture, independent control rods  191  that can accommodate positional variations may be used for each vane  150  and  151 . 
       FIGS. 5   a  and  5   b  show a front and side view, respectively, of the DuoVane (double-vane) embodiments wherein the roller bearings  161  are placed on the outside diameter of the glider rings  162  and  163 .  FIGS. 6   a  and  6   b  show an unassembled view of the machine shown in  FIGS. 5   a  and  5   b , respectively, showing additional detail. The DuoVane machines shown in  FIGS. 5 and 6  use roller bearings  161  such that the outside circumference of the glider rings  162  and  163  ride within bearings  261  that are installed in the bearing housings of endplates  10  and  30 . 
       FIG. 7  shows a similar embodiment to the embodiment shown in  FIGS. 5   a ,  5   b ,  6   a  and  6   c . In this embodiment, glider rings  262  and  263  ride on the outside of the roller bearings  261 . As shown, the roller bearings  261  are located on a bearing mount  265  that is concentric with the inside diameter of the stator bore of stator housing  20 .  FIGS. 8   a - e  shows additional detail of the assembly shown in  FIG. 7 , without showing the non-rotating components.  FIG. 8   a  shows a front view of the rotating components of the DuoVane assembly shown in  FIG. 7   b ;  FIGS. 8   b  and  8   c  show a front view of the rotating vane assembly and the vane counter balance, respectively, from one side and  FIGS. 8   d  and  8   e  show a front view of the rotating vane assembly and the vane counter balance, respectively, from an opposite side. In the preferred embodiment, this centering control rod  257  precisely engages vane holes of vanes  250  and  251  and prevents axial, side-to-side motion of the vanes  250  and  251  in rotor slots of rotor  240 . 
       FIG. 9  shows yet another embodiment quite similar to other DuoVane embodiments described above. The difference with the embodiment shown in  FIG. 9  is that instead of having vane axles extend across the entire vane  250  and  251 , vane axle stubs  270  and  271  are used and, as shown, are held in place by snap rings  270   a  and  271   a , respectively, or any other fastening means known to the art can be used to achieve the attachment or, in some designs a fastener is not required. Use of vane axle stubs relieves the need for cross-hole  72  in vane axle  70  ( FIG. 1 ) and also slightly eases the balancing of the rotating mechanism. 
       FIGS. 10 and 11  illustrate yet another embodiment also similar to the other DuoVane embodiments described above. The difference in the embodiment shown in  FIGS. 10 and 11  as compared to, say,  FIGS. 8 and 9 , is that the roller bearings  261  and bearing rings  280  straddle the vanes  285  (on each of the vane ends) and thus eliminate the overhang of stub axles  270  shown in  FIG. 9 . This embodiment not only stiffens the mechanism, but also shortens the machine somewhat. Also, the four vane bearing rings  280  equipped with balance voids  282  are all identical. Note as well, that the extensions  286   a  of endplates  286  (only one endplate is shown) provide the inner race for the bearings  261 , much as shown in  FIG. 7  with bearing mounts  265 . Also, as illustrated in the foregoing embodiments, the axle vane positioning rods  257  are used to keep the vanes centered within the endplates  286 . Finally, note that cross-slots  287  in vanes  285  are present to accommodate clearance for the in-board set of vane bearing rings  280 . 
     As previously discussed in regard to the MonoVane machine, the rotating vane/vane glider ring assemblies must be dynamically balanced about their center of rotation. In the case of the DuoVane machine two sets of rotating assemblies must reside with one another in a cooperative fashion. This is achieved by providing a vane axle pass-through void  275  as shown in  FIGS. 8 and 9 , so that the second vane  251  can simultaneously receive accurate radial and axial position control and to insure collective dynamic balance of the rotating vane assemblies that is required for proper machine operation. 
       FIG. 10   a  shows yet another example of the DuoVane apparatus embodiment shown in  FIG. 5   a  through  FIG. 9 ,  FIGS. 10   b  and  10   c  show a front view of the rotating vane assembly and the vane counter balance, respectively, shown in  FIG. 10   a  from one side and  FIGS. 10   d  and  10   e  show a front view of the rotating vane assembly and the vane counter balance, respectively, shown in  FIG. 10   a  from an opposite side. 
     In connection with achieving dynamic machine balance, as shown in  FIGS. 8 ,  9 ,  10  and  11  the ‘hot dog’—shaped voids  276 ,  277  and  282  (virtually any accommodating void shape would do) are present to counter-balance vane  251  and its companion vane axle stubs  270  and  271 . While the shaped voids  276  and  277  are shown as having a ‘hot dog’ shape, voids having alternative shapes may be substituted. These voids  276  and  277  are sized and located to insure that the outer rotating assembly, axially speaking, the one spanning the inner rotating assembly, renders the collective center of gravity very close to the actual rotational axis of the rotating assembly, thus canceling any centripetal out-of-balance forces. Voids, although the voids may be somewhat different, are also required in the glider rings of the ‘inner’ rotating assembly. These are shown specifically in  FIG. 9  as voids  276  which are, in this illustration, more pervasive (larger) than void  277  the vane axle pass through voids  275 . This is because the pass-through void  275  increases the mass void required to dynamically balance the axially inner rotating vane subassembly. 
     While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended.

Technology Classification (CPC): 5