The concepts of the present invention encompass a form of rotary machines embodying parallel and splayed axis shafts with eccentric and non-eccentric rotors. In the prior art, the axis of rotation is through the geometric center of the rotor, thereby limiting the possible configurations. Typical rotary engine patents use parallel axis configurations meaning that the axes of rotation are parallel to each other and all rotors rotate in a planar circular arc perpendicular to these axes. The shifting of the center of rotation away from the center of geometry (i.e., eccentricity) allows for multiple rotor configurations (four, five, and six). This concept of eccentricity has remained unused in rotor design because no one has sought to modify the basic philosophy of the prior Colbourne rotary concept and its relative uniqueness and simplicity. Of the many innovations that extend from the Colbourne concept, none of them have strayed from the fundamental concept of the Colbourne theme.
In addition, and related to this concept of eccentricity, is the concept of radial axis machines where the axis of rotation is skewed or tilted in a radial pattern around a central fixed axis. The tilting of the axis causes varying degrees of eccentricity to occur in the rotor design. This skewing condition of the axes culminates when the radial axes are perpendicular to each other at 90 degrees and eccentricity is zero. Moving from parallel axis to radial axis machines, where the axis of rotation is not parallel to the axes of adjacent rotors, allows for a greater diversity of rotary machines not before envisioned. This movement of the axis from parallel to radial generates machines where the rotors do not rotate on a plane but rotate on spherical surface.
History shows multiple patents that describe three or four rotor machines that are all based on parallel axis. This creates a machine where all rotors are revolving about parallel axis shafts and their construction geometries and rotational movements are on a planar surface. In addition, the axis of rotation falls directly through the center of the rotor shape (zero eccentricity). This limits the possible configurations to groupings of three or four rotors. Due to the geometries involved with keeping the rotors tangent to each other as they rotate through 360 degrees, parallel axis machines with a single volume chamber cannot be defined with more than four rotors. This does not mean that they can not be placed together in adjacent groupings to create more than one chamber, but in all cases, there can not be more than four rotors either applying work to or extracting work from the cycle of the machine.
In an eccentric configuration, the axis is moved off the center of the oval shaped rotor (referred to as eccentricity). This results in an extension of the four-rotor design and allows for the creation of five- and six-rotor configurations where six is the maximum practical configuration. Although seven rotors and above is geometrically possible, the resulting rotor configuration is not practical, since the resulting shape would not allow for a reasonable mechanical configuration. For example, the inclusion of an output shaft.
In the past, four-rotor design has been the basis for rotary machines. The introduction of eccentricity allows for five and six flat or planar rotor configurations. Five and six rotor configurations expose more surface area to the chamber, thereby increasing their possibility to do work for each machine cycle which also use the “teardrop” shape rotor where one tip has a radius and the other tip forms a vertex. These five- and six-rotor configurations create a natural port as the rotors move through their cycle.
It is true that the four-rotor configuration could be scaled or have multiple groupings to equal this work gain, but that would require a significant increase in machine size. Thus the five- and six-rotor rotary machines are far more efficient for a given physical size.
Although this machine depicts a typical arrangement for an engine configuration, this concept of eccentric rotors on a rotary machine could apply to other embodiments such as pumps. To get the rotors to work in unison and in co-rotation, a gear set is required that provides the phasing of the rotors to produce the working chamber.
The concept of eccentricity in rotor definition has not been used because no one has sought to modify the basic philosophy of the Colbourne rotary concept from its relative uniqueness and simplicity. Of the many innovations that extend from the innate beauty and simplicity of the Colbourne concept, none have strayed from the fundamental concept of the Colbourne theme until the ideas set fourth in this document.
The introduction of eccentricity into the rotary configuration creates the following benefits over existing parallel axis configurations: The dynamic (moving) porting simplifies the methods of engine cycling; Allows for multiple (4+) rotor configurations, operating in both parallel axis and non parallel axis configurations; Increased torque outputs due to the induced lever arm created from the offset axis; Increased work output due to the increased surface area the multiple rotors (4+) permit for a given chamber volume; Reduced physical size required to configure the machine; Larger chamber volumes for a given physical size; Easy assembly using bevel gears.
For parallel axis systems, the rotors are all moving on planes perpendicular to the axis of rotation.
The introduction of a radius tip at one or both ends of the rotor affects the eccentricity, thereby shifting the rotor rotation axis from the center of the rotor geometry. The addition of a radius tip causes several desirable outcomes: Radius tips create a chamber volume, which can be altered in size based on the application of the machine; A radius tip produces a complimentary surface that as the rotors interact with each other, there is more surface area in tangential contact rather than a singular vertex; A radius tip also creates a region of the rotor suitable for the placement of a load-bearing crankshaft.
Radial axis configurations of the rotary engine have also not been exploited in the past. Parallel axis embodiments are the common machine configuration. The introduction of eccentricity into the basic four-rotor configurations has allowed the creation of five- and six-rotor rotary machines. Eccentricity also allows us to move to radial axis configurations where the axis of rotor shafts are not parallel, but can be splayed from a central axis to form a right circular cone.
When one introduces a radial angle into the axis of rotation, the rotors can no longer operate in a planar or flat environment but must now rotate relative to a spherical surface. This radial angle or “splaying” of the shafts off of parallel introduces an eccentricity formed at the apex angles by the mapping of standard flat shapes (squares, pentagons and hexagons) onto spherical surfaces. Eccentricity is now formed naturally due to the radial array unlike in the flat conditions where one has the option to introduce it into their design. When dealing with radial arrays and spherical surfaces, there is a solution where the tip radius will maintain tangential contact with the sides of the adjacent rotor as it passes through its 360-degree cycle for any given amount of eccentricity due to apex angle and tip radius.
The addition of a radial tip is essential in the creation of a machine. As discussed previously, the radius tip allows for a volumetric area for either combustion or pump activities. The construction process is the same for the six-rotor lobe as it is for all other rotor designs. As with all other configurations described in this document, the resultant curve for the “long” side of the rotors is not a second order constant radius arc. It is a third order spline. Failure to describe it as such will yield rotor designs that will not work in “real life” applications.
A rotary machine having a plurality of rotor spindles conically arranged. An internal combustion machine: Having a plurality of rotor blades; Having a plurality of rotor spindles; Where each rotor blade has a rotor spindle attached thereto; the rotor spindles rotating about their centerlines; Where the centerlines of the rotor shafts are configured to lie on the surface of an imaginary cone.
A rotary machine utilizing a beveled planetary gear driven by rotor spindle pinion gears. An internal combustion machine: Having a plurality of rotor blades; Having a plurality of rotor spindles. Where each rotor blade has a rotor spindle attached thereto; the rotor spindles rotating about their center lines; Where the rotor spindles have pinion gears configured to mate with and turn a beveled (or conical) planetary gear mounted or formed on an output shaft.
A rotary machine having a plurality of rotor blades where the upper surface of the rotor blades lies on the surface of an imaginary sphere. An internal combustion machine: Having a plurality of rotor blades; Having a plurality of rotor spindles. Where each rotor blade has a rotor spindle attached thereto; the rotor spindles rotating about their centerlines; Where the top surfaces of the rotor blades lie on the surface of an imaginary sphere.
A rotary machine having rotor blades rotating about an axis that is offset from the center of the cross-sectional area of the blade. An internal combustion machine: Having a plurality of rotor blades; Where each rotor blade has a rotor spindle attached thereto; the rotor spindles rotating about their centerlines. Where the rotor spindles are attached to the rotor blades at a point that is offset from the center of the cross sectional area of the rotor blades.
A rotor blade for a rotary machine having a near “teardrop” shaped cross-section. The cross section is roughly an ellipse but with one pointed end. Changes to the shape of the cross section allow for the control of the compression ratio of the machine.
The invention comprises a rotary engine or pump having a plurality of rotor blades. The engine components may be constructed of ceramic or metal or composites thereof. Rotor shafts or spindles extend through each of the rotor blades (one rotor spindle per rotor blade). The rotor blades are housed in an area defining a combustion chamber. The combustion chamber is sealed with the exception of exhaust and intake ports and any orifices needed for ignition related elements.
The centerlines of each of the rotor spindles are canted at an angle from vertical, with each centerline lying of the surface of an imaginary cone. The top surface of each of the rotors is curved. The curvature matches that of the surface of a sphere of a given radius. The cross sectional area of the rotor blades gradually reduces/tapers from a maximum at the top of the blades to a minimum at the bottom of the blades—that is the blade are larger at the top than at the bottom. The rotor blades are fixed to the rotor spindles such that when the rotor blades rotate, so do their respective spindles. The rotor blades rotate about the centerlines of the rotor spindles.
The rotor blades of the five-rotor design have a “tear-drop” shaped cross-section. Also, in the five-rotor deign, the rotor blades are mounted to the rotor spindle at a point offset from the center of the cross sectional area of the blades (the cross section lying in a plane orthogonal to the rotor spindle centerline). In contrast, the rotor blades of the four-rotor design are mounted to the rotor spindles at the center (or nearly so) of the cross sectional area of the rotor blades and the rotor blades are symmetrical on either side of the rotor spindle with the exception of a small flat “notch” on one side of the rotors. The shapes of the rotor cross sections in both designs are derived from segments of second and third order curves.
The top of the rotor spindle extends beyond the rotor blade for a distance sufficient to allow for the installation of a bearing to hold the centerline of the shafts substantially stationary while allowing the spindles to rotate. A conical shaped bearing comprising a number of tapered needle bearings may be used to allow the spindles to rotate freely.
The lower or distal ends of the rotor shafts have tapered gears mounted thereto or formed thereon. The tapering of the gears is matched to the tapering of a planetary gear on an output shaft. A conically shaped sun gear sits in the center of the rotor spindles and holds the spindles in place against the output shaft. This gearing is configured for zero (or minimal) backlash operation. Any torque generated by forces applied to the rotor blades is therefore transferred through the rotor shafts to the central output shaft.
The gearing at the end of the rotor shafts also ensures that the rotor blades rotates synchronously. The timing of the rotor blades is adjusted so that during their rotation (or during a portion of their rotation in the five-rotor designs) each of the rotor blades is in contact (or nearly so) with an adjacent rotor blade. A volume inside the engine between the rotor blades is isolated. As the blades continue to rotate, the isolated volume decreases until a minimum volume is reached. After the point of minimum volume is reached, further rotation results in the isolated volume expanding in size. In the five-rotor design, the isolated volume is eventually released as the rotor blades continue to rotate.
In operation as an engine, a fuel mixture is introduced through an intake port. The fuel mixture is preferably hydrogen and oxygen, but a petroleum vapor (gasoline, etc.) and air mixture can be used. As the rotor blades rotate to form the isolated volume, the isolated volume then contains the fuel mixture. The fuel mixture is compressed as rotation continues until the point of greatest compression occurs. Just beyond the point of greatest compression, the isolated volume begins to expand and the fuel mixture is ignited. Ignition is preferably achieved through the use of a laser directed from the top center of the combustion chamber. The use of a laser can provide a cylindrical wave front for the resulting combustion as opposed to a spherical wave front that would be produced if a conventional point source of ignition were used. Spark plugs can, however, be utilized as well as other ignition methods, such as dieseling. The conical wave front combustion is preferred since the combustion forces would provide a more uniform pressure to the faces of the rotor blades.
As combustion progresses, the rotor blades are forced to turn as the isolated volume expands. After full expansion has occurred, an exhaust port is opened to allow the gasses inside the combustion chamber to escape. The cycle then begins again.
The engine may be configured as a two or four cycle engine or as a pump or compressor.
Other objects, features, and advantages of the present invention will be apparent from the written description and the drawings in which:
The splayed axis, four-rotor, four-cycle engine is illustrated in
The present invention comprises a rotary machine having a plurality of rotor blades (at least three) driven by the combustion of a fuel mixture. The machine components may be constructed of ceramic or metal or composites thereof. Rotor shafts or spindles extend through each of the rotor blades (one rotor spindle per rotor blade). The rotor blades are housed in an area defining a combustion chamber. The combustion chamber is sealed with the exception of exhaust and intake ports and any orifices needed for ignition related elements.
Referring specifically to
The centerlines of each of the rotor spindles are canted at an angle from central axis, with each centerline lying on the surface of an imaginary cone where the imaginary cone has a vertex angle less than 180 degrees and more than 0 degrees.
The rotor blades of the four-rotor design have an “oval” shaped cross-section as can be seen in
The rotor blades are fixed to the rotor spindles such that when the rotor blades rotate so do their respective spindles. The rotor blades rotate about the centerlines of the rotor spindles. In the four-rotor design, the rotor blades are mounted to the rotor spindles at the near center (slight eccentricity) of the cross sectional area of the rotor blades, and the rotor blades are near symmetrical with a small notch on one end of the rotors. In the five-rotor design, the rotor blades are mounted to the rotor spindles at a point significantly offset from the center of the cross sectional area of the blades (the cross section lying in a plane orthogonal to the rotor spindle centerline). The shapes of the rotor cross sections in both designs are custom designed based on splay angle, tip radius, sphere radius, and the number of rotors as shown in previous discussions.
The top of the rotor spindle extends beyond the rotor blade for a distance sufficient to allow for the installation of a bearing to hold the centerline of the shafts substantially stationary while allowing the spindles to rotate. A conical shaped bearing comprising a number of tapered needle bearings may be used to allow the spindles to rotate freely.
The lower or distal ends of the rotor shafts have tapered gears mounted thereto or formed thereon. The tapering of the gears is matched to the tapering of a planetary gear on an output shaft. The tapered pinion gears on the rotor spindles fit inside a “cupped” area of the output shaft. A conically shaped sun gear sits in the center of the rotor spindles and holds the spindles in place against the output shaft. This gearing is configured for zero (or minimal) backlash operation. Any torque generated by forces applied to the rotor blades is therefore transferred through the rotor shafts to the central output shaft.
The gearing at the end of the rotor shafts also ensures that the rotor blades rotate synchronously. The timing of the rotor blades is adjusted so that during a portion of their rotation each of the rotor blades is in contact (or nearly so) with an adjacent rotor blade.
The engine operation described below is, a four rotor, radial axis rotary engine configured to run in a four-cycle (stroke) configuration. Due to the radial axis configuration, the rotors are rotating on a spherical surface, and due to the eccentricity, the axis of rotation is offset from the center of the rotor shape creating a larger lever arm to perform work on during the combustion process. As the rotors rotate about their axis through 360 degrees, they create a variable sized chamber that undergoes compression and exhaust cycles. Power from the process is passed through beveled planetary gear set which is connected to a Power Take Off (PTO) ring gear which can then be attached to other devices such as transmissions, pumps, etc. as required. Intake and exhaust gases flow through the main pinion shafts and due to the placement of the intake and exhaust ports on the rotors themselves, we simplify the porting of this engine. Intake gases come in from a manifold affixed to the top of the engine case and exhaust gases are expelled down the same pinion shafts and out through the PTO. This process is illustrated in
In operation, (this description refers to the four-rotor design) a fuel mixture is introduced through an intake port. The fuel mixture is preferably hydrogen and oxygen, but a petroleum vapor (gasoline, etc.) and air mixture can be used. As the rotor blades rotate to form the isolated volume, the isolated volume then contains the fuel mixture. The fuel mixture is compressed as rotation continues until the point of greatest compression occurs. Just beyond the point of greatest compression, the isolated volume begins to expand and the fuel mixture is ignited. Ignition is achieved through the use of a spark plug fired from the top center of the combustion chamber.
Continuing with the combustion process, the rotor blades are forced to turn as the isolated volume expands. Eventually the rotor blades are no longer in contact with one another and the trapped volume of combusted gas is allowed to escape into the remainder of the combustion chamber. At this time the exhaust port is opened to allow the gasses inside the combustion chamber to escape. A vacuum may optionally pull these gasses out of the combustion chamber. The cycle then begins again.
It is the nature of this set of four rotors to revolve in a phased co-rotation at equal angular velocities provided by a beveled planetary gear set in which a range of reduction ratios may suit such purposes of the engine.
Intake and exhaust channels run through the (central) bores of the rotors and lead to ports on the sides of the rotors near the end of the 180 degree tip, with intake ports on the following side, exhaust ports on the leading side. In this configuration, the requisite porting channels are confined to the rotors only, leaving normal plenums effecting engine casing design.
The rotors are set on splayed axes, a configuration that expresses the invention of this design. Splay angles lead to a reporting of the rotor profile without effectively compromising the application of the four-cycle internal combustion process to this mechanism. Some of the advantages of containing a four-cycle internal combustion process in a rotary engine: fewer parts, smoother work cycle, higher power for size ratio, and a complete four-cycle process in one revolution of the rotors.
In addition, the offsetting of the rotor from the shaft (eccentricity) exposes a leveraging area on the face of the rotors that increases as the combustion progresses thereby increasing the available torque. The ‘eccentricity’ also effects the duration that the rotors remain in sliding (abutted) contact. There is a period of about 90 degrees, from 135 degrees to 225 degrees, in which a slight and gradual separation of the rotors occur (this compares to the overlap period in reciprocating piston engines). This separation is a function that follows as a result of splaying the axes but is of no consequence to the performance of the engine; the advantage of the ‘overlap’ in the reciprocating piston, internal combustion engine is not so viable in this design due to the nature of the rotor porting in this engine. If necessary, overlap is an option if the ports are arranged to sweep across each other. As it turns out, the period of slight separation of the rotors is of little consequence or little advantage and is a result of eccentricity.
The four semi-circular peripheral rotor pockets (volume between the rotors and the engine casing) work to our advantage. They are washed/fed by the intake rotor ports and create a volume for cooling as the rotors turn. During certain angles of rotation, some of the cooler gases are forced into the rotor exhaust ports diluting the exhaust and possibly providing oxygen for ‘after-burn’. In general, these swept volumes have no direct effect on the four-cycle process. Due to the shape of the rotors and the casing, the rotors freely clear the pockets (i.e., no sliding contact). The term Pocket Volume is used to describe the areas around the rotors throughout the cycle. It is not to be confused with the combustion chamber.
Based on the following diagrams, the basic cycles of the embodiment are described in roughly 15-degree increments.
Zero degrees (FIG. 9)—Engine is at TDC. fuel/air mixture is already in the central chamber and under pressure waiting for spark to ignite. Exhaust gasses from previous cycle are in the surrounding pocket volumes being ported through the leading edge of the rotor and out through the pinion shaft where it is exhausted from the engine. Throughout the expansion power cycle, pocket vapor (air) is driven into the exhaust ports at tips of rotors (approximately through 90 degrees of rotation). Pocket volume is at a maximum and combustion chamber volume at minimum. Maximum rotor surface exposed to pocket vapor.
Approximately 90 degrees (FIG. 10)—Exhaust ports are opening to the combustion chamber; exhaust cycle extends under rotor contact effectively to 150 degrees with another 30 degrees to “B.D.C.”.
135 degrees to 180 degrees (FIG. 11)—Rotors gradually separate after 180 degrees—Ports are in alignment for overlap. Overlap may extend as much as 20 degrees. In
Approximately 190 degrees (FIG. 12)—Intake ports open into central cavity. Exhaust ports open into pocket volume. Initial contact between the blades is made. During this portion of the rotation a volume inside the machine is isolated. As the blades continue to rotate the isolated volume decreases until a minimum volume is reached.
190 degrees to 270 degrees—Intake cycle. Exhaust ports are charged with pocket air.
Approximately 275 degrees—Compression cycle begins. Exhaust ports are ‘buffered’ by pocket air, hot side of rotors are cooled in pocket air, and Intake ports are charging pocket volume
360 degrees (FIG. 13)—After the point of minimum volume is reached, further rotation results with isolated volume expanding in size. Ignition occurs depending on timing advance.
The power stroke (cycle) lasts approximately 75 degrees.
At the 135 position, in which rotors are ‘square’ to each other, the point of tangency between the upper face of the rotor side and the short end tip radius begins to separate. The short rotor end tip radius can remain in tangency until this position due to the declining curvature of the true arc of the rotor side profile because of the eccentricity expressed at the 15° splay.
The ‘overlap’ end profile appears to be a ≈90 degree arc but is in fact two ≈45 degree splines symmetrical about the major axis of the rotor—the two splines meant to remain in contact (tangency) to (with) the ‘upper’ rotor sides. This leaves compression and expansion strokes in rubbing contact for 135 degrees, and effective closure for approximately 165°.
At 225 degrees is where the tip radius on the end of the rotor begins tangency with adjacent upper rotor side at the end of the overlap.
Another porting method involves the use of opposing pairs of head ports; one pair for exhaust and the other for intake. This is not a preferable porting method, but still works.
In
As seen in
Referring to
The fuel/air mixture is fed into four of the eight chambers due to low pressures generated by rotor movement. These four chamber act as intake and pre-compression chambers. Check valves are used to control the direction of the fuel/air mixture flow. During this intake cycle, the alternate four chambers are in their working cycle of firing and combustion. As the rotors 128 continue to rotate, the fuel/air mixture then passes from the pre-compression chambers into the adjacent chamber via transport channels that become open or “exposed” as the rotors pass over inlet ports. This is phased to coincide with the compression and firing of the adjacent chambers. The cycle then repeats itself in an alternating sequence creating the two cycles of the engine.
The operation of the two-cycle engine 120 is illustrated in
The spark plug 126 fires and the rotors 128 are turned due to expansion of the gases. The rotor 128 is at approximately 100 degrees in its expansion cycle in
At approximately 120 degrees
At 180 degrees (
At approximately 230 degrees (
In
In
Six identical, bi-polar rotors 156 cooperate in spherical order creating eight cavities. Operating pressures are exerted evenly on both ends of the rotor with all six rotors 156 co-rotating in the same angular direction and at the same angular velocity. Input design parameters include the radius of the operating sphere and the tip radius of the rotors 156. The embodiment shows a planetary gear set used to transfer torque evenly and to synchronize the machine. This gear set can be internal or mounted externally to the rotors 156 as required.
In operation, steam or compressed air is channeled into the center spherical chamber through the main rotor shafts 152. All porting, venting and intake is done by the opening (exposing) or closing (hiding) of ports by the rotation of internal parts as they rotate through 360 degrees. Rotating valves connected through a planetary gear set, phased with the rotation of the rotors, allow the “fuel” to pass into the rotor chambers to extract the work. Once the work has been done, the spent fuel is released through openings at the leading ends of the rotors and vented through channels 157 in the rotors 156. As the rotor 156 rotates, the channels 157 align with output vents 153 in the engine case 151. The internal rotary valve assembly 163 uses a set of transfer pinions 167 set between the beveled gears 164 on the rims of the rotary valves 163. The transfer pinions 167 allow for the direct transfer of torque from opposing rotors.
In
Although the pictured embodiment is of a pump, the concepts and basic machine philosophies can be easily adapted to work as combustion engines also.
A parallel five lobe machine 175 can be configured into (but not limited to) a combustion engine (four- or two-stroke), steam or pneumatic engine, or fluid pump.
“Dual Acting Pump” refers to a pump that is pumping and sucking fluid simultaneously during various parts of the stroke or cycle of the engine. A piston style dual acting pump is pumping fluid on one side if the piston and sucking fluid on the other. The Parallel Five lobe cycle is based on rotation of the lobes 184 where various positions and sides of the lobes determine whether the lobe is drawing or pushing fluid.
An examination of the pump reveals that there are two distinct chambers within the pump. One chamber 192 is between the lobes and the outer wall of the pump and the other 191 is towards the center of the pump whenever the lobes seal against themselves. During the cycle of the pump, ports 1-5 (182) will always be working in the same direction, meaning that fluid is either coming into the pump 175 through ports 1-5 simultaneously or exiting the pump 175 simultaneously. Whereas port six (190) will always be acting in an opposite manner as compared to ports 1-5. Within the manifold 180, uni-directional valves open and close at each port location. For example, when the inner chamber is sucking fluid, the input valve will open and the output valve will shut automatically (i.e., pressure controlled). The valves would then reverse their position to allow fluid to flow from the pump.
The basic operation of the pump through one complete cycle is as follows.
In position #1 of
This position shows the two chambers of fluid movement. The top dead center position creates the smallest inner chamber 191 area (center of the pump) defined by the tips of the lobes 184. In this position, the smallest amount of fluid exists in the inner chamber 191 with the largest amount of fluid between the sides of the lobes and the sidewalls of the pump housing (outer chambers 192). At the top dead center position, the inner chamber has just finished pumping fluid out and the outer chambers have just finished sucking fluid in.
In position #2 of
At each corner of the pentagon shaped manifold 180 is a pair of ports 182. One port is for extracting fluid from a reservoir into the pump (sucking) and the other is for pushing the fluid out of the pump. Inside each port is an automatic valve that will only allow fluid to flow one way based on pressure differentials, i.e., one valve will only open into the pump and the other will open out from the pump.
The sixth pair of ports 190 is in the center of the pump manifold and acts the same as the ports on the corners. The center ports are of a different diameter. The diameters of the ports are adjusted based on the size of the pump, lobe geometry and the amount of eccentricity. The five corner ports 182 are working together and opposite the center port 190, which must be taken into account when calculating flow volumes in and out.
The position shown in
At approximately 90 degrees of rotation, the tangency seal between the lobes 184 is about to separate. The actual angle of rotation that this occurs depends on the tip radius of the lobes 184 and therefore the radius of the sides of the lobe. At this stage, the fluid volume of the inner chamber 191 is at a maximum and the fluid volume of the outer chamber is at a minimum.
This is the end of the work cycle of the pump. For about 180 degrees of rotation (90 to 270 degrees) the tangency connection between the rotors 184 is separated and pressures between the two chambers are equalized.
In
As the lobes 184 break away from being tangential to one another, the inner and outer chambers (191,192) combine into one big chamber. During this time of “no contact” between the lobes, fluid is not flowing in or out of the pump, therefore resulting in a dead zone of the rotation.
An optional design in a pump configurations would be to combine two five lobe pumps and time them to be 180 degrees out of phase so that there is a continuous pump pressure through an entire cycle and therefore eliminate the dead zone.
In
At the end of the dead zone, contact between the lobes occurs again thus sealing the inner chamber from the outer chamber 192. At this position, the inner chamber 191 is at maximum volume while the outer chamber 192 is at minimum volume. During the next few degrees of rotation, the power stroke of the pump begins, and fluid will begin to be pushed out of the inner chamber 191 and drawn into the outer chamber 192.
The power stroke is shown in
From 270 through 360 degrees of rotation, the pump 175 is exhausting fluids from the inner chamber 191 and sucking fluids into the outer chambers 192. This is the reverse flow scenario that occurred from 0-90 degrees of rotation.
In summary, the pump is working from 270 degrees through 360 (i.e., 0 degrees) to 90 degrees and is idle from 90 to 270 degrees. The inner chamber 191 switches from pumping to sucking at 0 degrees top dead center at the same time the outer chambers 192 go from sucking to pumping thus the dual acting nature of the pump.
The rotation of the lobes originates from a shaft at the bottom of the pump. The gearing configuration shown is 1:1 but the pump can be geared up or down as required.
This application claims the benefit of U.S. Provisional Application No. 60/662,941, filed Mar. 16, 2005.
Number | Date | Country | |
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60662941 | Mar 2005 | US |
Number | Date | Country | |
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Parent | 11378118 | Mar 2006 | US |
Child | 12168654 | US |
Number | Date | Country | |
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Parent | 12168654 | Jul 2008 | US |
Child | 12207377 | US |