FLUID PROPULSION DEVICE

DESCRIPTION Background Art The present invention relates to a device for propelling a fluid or a pump, and more particularly concerns a device moving a fluid or attached body through a medium such as water.

Naval architects have long recognized the significant disadvantages of screw propeller technology, and more recently impeller technology, for moving a vessel through water. For example, such technology has a relatively narrow range of efficiency, limited by propeller stall at low speeds and cavitations at high speeds. Cavitation occurs when the leading edge of the propeller or impeller creates a pressure less than the ambient water pressure causing the fluid medium to rupture and create vapor bubbles which, upon their implosive collapse, cause pitting on the propeller surface and also a highly distinctive acoustic signature. Cavitation is the limiting parameter on high-speed marine propellers. In terms of efficiency, propellers not only impart a huge amount of wasted angular momentum to the propelled water stream, but also shed tip vortices, which contribute to the overall drag of the propeller system and lower the overall propulsive efficiency. The inherent large angular inertia and angular momentum prevents the propeller or impeller system from achieving high forward burst speeds and high stopping speeds. In addition, the propeller system has an asymmetrical efficiency between the ahead and astern modes, since it is designed primarily for forward propulsion. Propeller and impeller systems are also highly susceptible to damage. Even comparatively minor damage to the blades causes a significant degradation in performance. Thus, it is a disadvantage in maintaining present propeller systems in good working condition for a long period of time without degradation of the propeller and results in decreased efficiency of the system.

Propeller and impeller systems also require a rotary transmission system, which imposes a huge disadvantage on the propulsion system due to its large mass, vulnerability to break down (principally at rotary seals), and its large angular inertia and angular momentum. The disadvantage of rotary transmission systems further includes the need for sealing at the fluid/system interface. This inevitably results in leakage into the vessel and inefficient operation of the system.

Maintainability of propeller and impeller systems is also a problem. Because present propeller and impeller systems use rotary transmission systems, maintenance of such systems can be time consuming and problematic. Often when propellers need repair or replacement, the

entire propeller shaft, including bearings, seals, and the like must be removed as well. This results in significant amount of work, time and expense. Thus, there is a need for a propulsion system that is easily replaced or maintained, that is easily accessed for repair and maintenance, and that does not require removal of associated equipment during such repair or maintenance. Several patents disclose linear pumps for propelling a vessel through water and moving a fluid, including U.S. Patent Nos. 6,352,455; 6,464,476 and 6,607,368, the contents of which are hereby incorporated by reference in their entirety. Another patent, U.S. 6,860,770, discloses a method and device for low-noise underwater propulsion and for reducing hull drag, the contents of which are hereby incorporated by reference in their entirety. Another disadvantage of present propeller and impeller systems is noise. In many marine and submarine vessels, noise is a significant factor in maintaining stealth. In particular, military craft, such as surface ships and submarines require significantly reduced noise levels for all systems in order to avoid detection by a third party and also to improve detection of third parties, with a lower acoustic signal/noise threshold. Thus, there is a need for a propulsion system that operates at relatively low sound and vibration levels so as to avoid detection by any third party and improves its own acoustic detection ability.

Summary In accordance with one embodiment of the present invention, a propulsion device is provided. The device includes first and second end plate assemblies. The first end plate assembly has a first end cap and a first drive member thereon. The drive member has a plurality of arcuate openings extending radially and tangentially outwardly from the inner radius of said first drive member. The second end plate assembly is spaced apart from the first end plate assembly. The second end plate assembly has a second end cap and a second drive member. The second drive member has a plurality of arcuate openings extending radially and tangentially outwardly from an inner radius of the second drive member. The propulsion device further includes inner and outer chambers. The outer chamber is sealably formed between the first and second end plate assemblies. The outer chamber has at least one outer chamber intake valve located on the first end plate assembly and at least one outer chamber exhaust valve located on the second end plate assembly. The inner chamber is concentrically located within the outer chamber and between the first and second end plate assemblies. The inner chamber has at least one inner chamber intake valve located on said first end plate assembly and at least one inner chamber exhaust valve located on said second end plate assembly. The inner chamber comprising a plurality of elongated, overlapping, v-shaped plate members longitudinally aligned

between the first and second end plate assemblies. Each v-shaped plate member has an apex and two side portions extending angularly from the apex. The side portions form an obtuse angle therebetween. Each end of the end plate member is slidably connected to the first and second end drive members. The propulsion device also includes a power source for rotating the first and second drive members. In use, the volume of said inner chamber expands when said first and second end drive members rotate causing the v-shaped plate members to move radially outward causing fluid to flow into the inner chamber from the inner chamber intake valve. As volume in the inner chamber expands, volume in the outer chamber decreases and thus fluid flows out of the outer chamber through the outer chamber exhaust valve. Similarly, the volume of the inner chamber then decreases when the first and second drive members are rotated in the opposed direction causing the v-shaped plate members of the inner chamber to move radially inward thus causing fluid to flow out of the inner chamber through the inner chamber exhaust valve. As volume in the inner chamber declines, volume in the outer chamber increases as fluid is drawn in through the outer chamber intake valve. The continuous flow of fluid through the inner and outer chambers creates a propulsion force for moving a vessel through a body of fluid.

An alternative aspect of the present invention involves a pump. The pump of the present invention includes first and second end plate assemblies. The end plate assemblies are spaced apart from one another. The pump of the present invention further includes an outer chamber sealably formed between the end plate assemblies. The outer chamber has at least one outer chamber intake valve located on the first end plate assembly and at least one outer chamber exhaust valve located on said second end plate assembly. The pump of the present invention further includes an inner chamber concentrically located within the outer chamber and between the first and second end plate assemblies. The inner chamber has at least one inner chamber intake valve located on the first end plate assembly and at least one inner chamber exhaust valve located on the second end plate assembly. The inner chamber comprises a plurality of elongated, overlapping, v-shaped plate members longitudinally aligned between the first and second end plate assemblies. Each v-shaped plate member has an apex and two side portions extending angularly from the apex. The side portions forming an obtuse angle therebetween. Each end of the end plate member is slidably connected to the first and second end plate assemblies. The pump of the present invention further includes a drive means for moving the v-shaped plate members between contracted and expanded positions. In use, when the drive means causes the v-shaped plate members to move radially outward, the volume of the inner chamber expands, causing fluid to flow into the inner chamber from the inner chamber intake valve. As volume in the inner chamber expands, volume in the outer chamber decreases and thus fluid flows out of

the outer chamber from the outer chamber exhaust valve. Similarly, when the drive means causes the v-shaped plate members to move radially inward, the volume of the inner chamber then decreases, thus causing fluid to flow out of the inner chamber through the inner chamber exhaust valve. As volume in the inner chamber declines, volume in the outer chamber increases as fluid is drawn in through the outer chamber intake valve.

Features and advantages of the present invention will become more apparent in light of the following detailed description of some embodiments thereof, as illustrated in the accompanying figures. As will be realized, the invention is capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and the description are to be regarded as illustrative in nature, and not as restrictive.

Brief Description Of The Drawings

FIG. 1 is an exploded perspective view of a fluid propulsion device according to the present invention. FIGs. 2 and 3 are front views of an intake end plate assembly for use with the fluid propulsion device shown in FIG.l.

FIGs. 4 and 5 are front views of an exhaust end plate assembly for use with the fluid propulsion device shown in FIG.1.

FIGs. 6 is an exploded elevation view of the intake end plate assembly shown in FIGs. 2 and 3.

FIGs. 7 is an exploded elevation view of the exhaust end plate assembly shown in FIGs. 4 and 5.

FIG. 8 is an exploded elevation view of a fluid propulsion device according to the present invention with the end plate assemblies exploded away from the ends of the outer housing.

FIG. 9 is an exploded perspective view of another embodiment of a fluid propulsion device according to the present invention wherein a portion of the outer housing has been cut away.

FIGs. 10 and 11 are exploded perspective views of a third embodiment of a fluid propulsion device according to the present invention wherein the end plate assemblies are exploded away from the ends of the outer housing and shown in a fully closed position and a fully open position, respectively, and wherein a portion of the intake valve is shown in phantom.

FIG. 12 is an exploded perspective end view of a portion of the fluid propulsion device according to the present invention wherein the end plate assemblies are exploded away from the ends of the outer housing and including a diverter valve.

FIG. 13 is a close up perspective view of the diverter valve shown in FIG. 15 in an open position and a closed position.

FIG. 14 is a perspective view of a rigid plate member for use with the fluid propulsion device shown in FIG.1.

FIG. 15 is a schematic cross-section view of the fluid propulsion device shown in FIG.l.

FIG. 16 is a perspective view of a portion of the fluid propulsion device shown in FIG.l including a motor.

Figure 17 is a perspective sectional of an alternative embodiment of the present invention.

Figure 18 is a schematic representation of the operation of an alternative embodiment of the present invention. Figure 19 is a front view of an alternative embodiment of the present invention as fitted to a shallow water craft.

Figure 20 is a schematic representation of the present invention where the propulsion units are connected in series.

Figure 21 is a schematic representation of an alternative embodiment of the invention shown in Figure 20.

Figure 22 A&B are sectional and front views of the present invention with the use of a liner enclosing the inner and outer chambers.

Figure 23 is a front view of an alternative embodiment of the present invention incorporating a cutter head.

Detailed Description

An embodiment of a fluid propulsion device according to the present invention is shown in Figure. 1 and generally designated at 40. The device 40 comprises a hollow, cylindrical outer housing 42 and a hollow, quasi-cylindrical inner shell 44 disposed within the outer housing 42. The inner shell 44 is preferably concentric about the central longitudinal axis of the outer housing 42.

End plate assemblies 46, 48 are adapted to be sealingly fixed at each end of the outer housing 42. Referring to Figures. 2-5, each end plate assembly 46, 48 comprises an end cap 45, a drive plate 47, and a capture ring 49. The end cap 45 is a circular disc having a large central opening 58 and a plurality of openings 62 circumferentially spaced adjacent to the periphery of the end cap 45. The end cap 45 has a plurality of radial slots 60 (Figure. 1) extending between the central opening 58 and the peripheral openings 62. The drive plate 47 is also a circular disc having a large central opening 59. The drive plate 47 has a plurality of circumferentially spaced arcuate openings 61, which extend radially and tangentially outwardly from the central opening 59. Referring to Figures 6 and 7, the drive plate 47 is rotatably received in a corresponding recess in the outer surface of the end cap 45. The capture ring 49 is fixed to a shoulder in the outer surface of the end cap 45 for holding the drive plate 47 in place for rotation with respect to the end cap 45.

As best seen in Figure 8, the length of the inner shell 44 is such that the ends of the inner housing engage the flat inner surface of the end caps 45 when the end plate assemblies 46, 48 are secured to the outer housing 42. The inner surfaces of the end caps 45 may be coated with TEFLON®, a fine diamond material, or a similar substance to create a sealing, low friction surface between the ends of the inner shell 44 and the end caps 45.

When the fluid propulsion device 40 is assembled, the inner shell 44 and the end caps 45 define an inner chamber 54. An outer chamber 56 is defined by the outer surface of the inner shell 44, the inner surface of the outer housing 42 and the end caps 45. hi one embodiment, the outer housing 42, inner shell 44 and end plate assemblies 46, 48 may be made from a substantially rigid material. For example, metals resistant to corrosion, such as coated carbon steel, certain stainless steels and bronze, are suitable. High impact plastic, toughened rubber, laminates or composites, or a combination of these materials, can also be used for the material of the fluid propulsion device 40.

When the end plate assemblies 46, 48 are mounted to the outer housing 42, the central opening 58 in the end caps 45 opens into the inner chamber 54 of the inner shell 44 for allowing fluid flow into and out of the inner chamber 54. The peripheral ports 62 in the end caps 45 open into the outer chamber 56 for allowing fluid flow into and out of the outer chamber 56. One end plate assembly 46 functions as a leading, or intake, end plate and the other end plate assembly 48 functions as a trailing, or exhaust, end plate.

Referring to Figures. 1 and 9, one-way valves 66 are disposed in the central opening 58 in the end caps 45. The valve 66 in the intake end plate assembly 46 opens into the inner chamber 54 and functions as an intake valve, and the valve 66 in the exhaust end plate assembly

48 opens into the inner chamber 54 and functions as an exhaust valve. Similarly, valves (not shown) may also be disposed in the peripheral ports 62 in the end caps 45 opening into the outer chamber 56 and function as intake valves and exhaust valves. The intake valves and exhaust valves cooperate to facilitate selective unidirectional fluid flow through the fluid propulsion device 40 from the intake end plate assembly 46 to the exhaust end plate assembly 48.

Preferably, the valves 66 opening into the inner chamber 54 are full bore valves so that a solid body with a diameter less than the bore of the valves can pass through the fluid propulsion device 40. Although the fluid propulsion device 40 shown in the FIGs. and described herein has a single opening 58 in each end cap 45 opening into the inner chamber 54 and a plurality of openings 62 in each end cap 45 opening into the outer chamber 56, it is understood that any number of openings into the inner chamber 54 or the outer chamber 56 may be provided. Moreover, the number of openings in one end cap 45 into a respective chamber does not have to equal the number of openings in the opposite end cap 45 into the same chamber.

The Figures illustrate use of COTs-type (commercial off the shelf) check valves 66 , which may comprise polymer reeds, or pointed flaps, that are in a full flow configuration similar to that of a human heart valve. It is understood that other conventional one-way valves may be used with the fluid propulsion device 40 according to the present invention, including, but not limited to, check valves, as well as flapper, bicuspid, ball-and-seat, and disk-and-seat type valves. The valves may be cushioned or silenced and may be closed completely or incompletely. Further, the valves may be positioned in the central opening 58 in the end caps 45 as shown in the figures, or the valves may be positioned upstream or downstream of the end plate assemblies 46, 48 as long as they are in fluid communication with the inner and outer chambers 54, 56. For example, Figures 10 and 11 show valves 66 positioned in the outer ends of cowling members 68 affixed over each of the end plate assemblies 46, 48. Alternatively, a diverter valve assembly 70 may be provided (Figure 12). The diverter valve assembly 70 may be mounted on one or both end plate assemblies 46, 48. The diverter valve assembly 70 functions as a one-way valve for the either the inner chamber 54 or the outer chamber 56. In use, the diverter valve assembly 70 can selectively allow fluid flow into or out of either the inner chamber 54 or the outer chamber 56 while preventing back-flow through the associated end cap 45. For example, Figure 12 shows a diverter valve assembly 70 associated with the exhaust end plate assembly 48. Flow from the outer chamber 56 is allowed when the diverter valve assembly 70 is in the closed position (Figure 13). Flow from the inner chamber 54 is allowed when the diverter valve assembly 70 is open. In this embodiment of the fluid

propulsion device 40, the plurality of peripheral openings 62 into the outer chamber 56 are flow- through openings.

Referring now to Figure 14, the inner shell 44 comprises a plurality of elongated, overlapping V-shaped plate members 80. The plate members 80 include an apex portion 82 and two side portions 84, 86 extending angularly away from the apex portion 82. The shape of the plate members 80 results in an inner housing 44 which generally resembles a multi-faceted cylinder wherein each plate member 80 provides a facet of the cylinder. The number of facets of the multi-faceted cylinder may range from about 4 to about 16. The preferred number of facets is about six. The side portions 84, 86 form an obtuse angle 85 relative to each other. In the case of six facets, the angle 85 between each of the two side portions would be 120 degrees.

The plate members 80 slide relative to one another in the planes of the adjacent side portions 84, 86, which motion causes expansion and contraction of the inner shell 44. In one embodiment, a first side portion 84 of each plate member 80 has a longitudinal groove 88 open at each end. The plate members 80 are arranged such that the second side portion 86 of each plate member 80 is slidingly received in the groove 88 in the first side portion 84 of an adjacent plate member 80 in a tongue-and-groove arrangement (Figure 15). To facilitate the sliding motion of the plate members 80, the plate members may be coated with a lubricant, or the plate members 80 may be made of a self-lubricating material, which also provides a seal. Alternatively, elongated rubber wiper blades (not shown) may be axially disposed between the grooves 88 for providing a seal between adjacent plate members 80. A system including a motor 92 is operatively connected to a drive plate 47 for driving the rotation of the drive plate 47 is shown in Figure 16.

It is understood that the relative sliding motion of the plate members 80 can be accomplished by any of a number of means. For example, the inner shell 44 may be comprised of plate members 80 wherein both side portions 84, 86 of alternating plate members 80 have either grooves or are solid. In another embodiment, not shown in the figures, the overlapping side portions 84, 86 of the plate members 80 include a plurality of keyways longitudinally spaced along the first side portion 84. The keyways movably fit into a plurality of corresponding keyways in the second side portion 86 of an adjacent plate member. In a further embodiment, both side portions 84, 86 of the plate members 80 have a plurality of longitudinally spaced grooves which slidingly fit into corresponding grooves in the adjacent plate member.

A drive mechanism is provided for displacing the plate members 80 inwardly and outwardly for causing expansion and contraction of the inner shell 44. In the embodiment as shown most particularly in Figure 8, pins 90 are fixed to the apex portion 82 at the ends of each

plate member 80. The pins 90 are operatively connected to a drive mechanism for moving the pins 90 radially inwardly and outwardly. A suitable drive mechanism in this embodiment comprises the end plate assemblies 46, 48, including the drive plates 47. Specifically, each pin 90 extends through one of the radial slots 60 in the end caps 45 and is received in one of the arcuate openings 61 in the drive plates 47. The inner ends of the openings 61 correspond to the minimum diameter of the inner shell 44, and the outer ends of the openings 61 correspond to the maximum diameter of the inner shell 44. Rotation of the drive plates 47 in one-direction causes the pins 90 to move inwardly in the slots 60 in the end caps 45 and openings in the drive plates 47, and rotation of the drive plates 47 in the other direction causes the pins 90 to move outwardly in the slots 60 and the openings 61.

Direct drive mechanisms are also suitable. For example, a piston (not shown) may be operatively connected to each plate member 80 for pulling or pushing the plate members 80 radially outwardly or inwardly, respectively. Another form of direct drive mechanism may comprise at least one linear motor (not shown) operatively associated with each plate member 80. For example, a plurality of radial electric motors coupled with a worm gear may be used to drive the plate members 80. It is understood that any conventional linear drive mechanism may be employed within the scope of the present invention.

In another embodiment of a direct drive mechanism, magnetic force may be used to expand and contract the inner shell 44. In this embodiment, the plate members 80 are electromagnetically powered, or may comprise a permanent magnet or a combination of permanent and electromagnets. For example, a portion of each plate member 80 may be formed from electromagnetic material or house an electromagnet. Power to the plate members 80 may be cyclically varied for reversing the polarity and controlling relative movement of the plate members 80. A coiled electronic field can be used to produce a solenoid-like movement of the plate members 80.

The selected drive mechanism is preferably actuated by umbilical power sources, that is, hydraulically, pneumatically, electrically and the like, or using a self-contained source, such as batteries. A control assembly or a programmable logic controller (not shown), such as a computer, may regulate operation of the fluid propulsion device 40 for cyclically controlling the expansion and contraction of the inner shell 44 in a manner which varies the volume of the inner chamber 54 and the outer chamber 56 thereby propelling fluid through the device 40. Low power consumption of the fluid propulsion device 40, coupled with the ability to pulse power, makes the device 40 function well with renewable energy sources, such as solar, wave or wind power. In such an implementation, the batteries operatively associated with the fluid propulsion

device 40 can be charged from the renewable energy source. The batteries can be tapped when necessary for, for example, station keeping of a vessel or a continuously sensing survey vessel patrolling a prescribed route.

The fluid propulsion device 40 according to the present invention may be constructed utilizing dimensions appropriate to a desired application. Because of the absence of gearing, a transmission shaft and a lubrication system, the size of the device 40 is scalable for a wide range of applications ranging from a tiny arterial pump to a propulsion unit for an icebreaker, for example, or a station-keeping propulsion unit for a semi-submersible oil-drilling rig. An important parameter is the length to diameter ratio, wherein the diameter is the maximum expanded diameter of the inner chamber 54 of the device 40. For example, where a compact fluid propulsion device 40 is required to deliver a large number of thrusts in bursts, the ratio can be as low as about 1.5:1. Whereas, a fluid propulsion device 40 which is required to deliver high speeds or sustained performance at high efficiency, the length to diameter ratio can be as high as about 12:1. For a normal range of applications, a ratio of about 4: 1 is suitable. In use, the sequential expansion and contraction of the inner shell 44 results in variation of the volume of the inner chamber 54 and the outer chamber 56, which causes intake and discharge of water from the chambers 54, 56. In the embodiment shown in the figures, on the expansion stroke, the drive plates 47 are turned in a counter-clockwise direction causing the pins 90 to move radially outwardly in the openings 61 in the drive plates 47 and the slots 60 in the end plates 45. As the pins 90 move outwardly, the plate members 80 separate, sliding with respect to one another and causing the volume of the inner shell 44 to expand. Upon expansion of the inner shell 44, fluid is drawn into the inner chamber 54 through the one-way valve 66 in the opening 58 in the intake end plate 45 while the one-way valve 66 in the exhaust end plate 45 remains closed. Concurrently with the expansion of the inner shell 44, the outer chamber 56 will decrease in volume, expelling the fluid in the outer chamber 56 through the ports 62 in the exhaust end plate 45. When the expansion stroke is completed, the inner chamber 54 is full with fluid and the outer chamber 56 is exhausted.

The contraction stroke is initiated by turning the drive plates 47 in the opposite direction causing the pins 90 to move radially inwardly in the openings 61 in the drive plates 47 and the slots 60 in the end plates 45. As the pins 90 move inwardly, the second side portions 86 of the plate members 80 slide into the grooves 88 of the first side portions 86 of the immediately adjacent plate members 80, thereby decreasing the diameter of the inner shell 44 resulting in a decrease in the volume of the inner chamber 54. Upon contraction of the inner shell 44, fluid is drawn into the outer chamber 56 through the openings 62 in the intake end plate 45. The one-

way valve 66 in the opening 58 in the exhaust end plate 45 opens for expelling the fluid in the inner chamber 56, while the one-way valve 66 in the intake end plate 45 closes. When the contraction stroke is completed, the outer chamber 56 is full with fluid and the inner chamber 54 is exhausted. Cyclical expansion and contraction of the inner shell 44 generates a substantially continuous flow of fluid through the end plate assemblies 46, 48. The discharge of fluid produces thrust. The stroke length in either direction may be full or partial.

The contraction and expansion of the inner housing 44 provides a quasi-square wave propulsion, which is superimposed upon the inner chamber from the outer chamber. In order to make propulsion smoother, the drive plates 47 can be made to move out-of-phase with one another. In this implementation, on the expansion stroke, the drive plate 47 associated with the intake end plate assembly 46 turns first, expanding the inner shell 44 at the intake end, followed by the drive plate 47 associated with the exhaust end plate assembly 48, which begins to expand after the inner shell 44 at the intake end is almost fully expanded. When the drive plate 47 at the exhaust end plate assembly 48 is fully rotated, the drive plate 47 at the intake end plate end assembly 46 reverses for contraction of the intake end of the inner shell 44. Reversal of the drive plate 47 at the exhaust end plate assembly 48 begins after the inner shell 44 at the intake end plate assembly 46 is almost fully contracted.

Another means for eliminating peaks in the propulsion curve is to use semi-rigid material for the plate members 80. Semi-rigid plate members 80 will flex upon initiation of a contraction stroke or an expansion stroke and return the stored potential energy at the end of the stroke. The flexure absorbs some of the stress on the initiation of the expansion and contraction strokes and yields up this force at the end of the stroke.

In the embodiment of the fluid propulsion device 40 according to the present invention including the diverter valve assembly 70, fluid flow through the device 40 can be reversed when the diverter valves are used in conjunction with chamber openings 58, 62. Since the device 40 is fully symmetrical, a reversal of the diverter valve assemblies 70, in opposition at the end of the device 40 with respect to the input and output chambers, effectively reverses the fluid flow through the device 40. In this manner, forward propulsion of the device 40 can be quickly and efficiently switched to reverse propulsion.

In one application, the fluid propulsion device 40 may be secured to a vehicle. The vehicle may be a vessel which the device 40 moves or propels through a fluid body, such as a body of water. This arrangement may have particular utility in powering submarines, underwater pods, boats or ships. A fluid propulsion device 40, or a plurality of devices, engaged with a

vessel may provide relatively quiet propulsion. The fluid propulsion device 40 can also enhance the maneuverability of a conventional marine vessel when used as either a bow thruster, an active rudder, or both. In addition, because there is no propeller or impeller, the system is more efficient and there is less maintenance and repair. This results in a more efficient, more reliable, less expensive system.

In addition, because the propulsion system of the present invention is essentially self- contained, it is easy to repair and replace. In the event of a system failure, a new system may be installed in a relatively short period of time where the conventional systems required weeks or months to repair or conduct routine maintenance. Also, because there are fewer moving parts, the system of the present invention is less likely to fail and thus less likely to need repair or maintenance.

The fluid propulsion device 40 according to the present invention 40 may also be used as a linear pump for moving fluid, such as water, oil, air, and the like. The device 40 may be used to move any fluid in numerous industrial, commercial, recreational, medical, astronautical, aeronautical, or military applications, including sewer systems, wastewater treatment, and the like. In another application, the fluid propulsion device 40 may be used to move fluids necessary to hydraulically operate machinery and equipment, including, but not limited to, submarines, boats, airplanes, aerospace and spacecraft. In all such applications, the flexibility in the dimensions of the fluid propulsion device 40 allows the device to be positioned within a conduit contiguous with current piping.

As a pump, the present invention is also self contained. As such, its replacement is easy and quick. Because it is an in-line component, the pump of the present invention may be replaced quickly and cleanly. If the pump of the present invention needs replacement, it can be easily isolated, removed and replaced. This minimizes any down time of the system and costs as a result of lost productivity. It should also be noted that because the present invention is self contained, it may be easily and inexpensively retrofitted on equipment and systems presently using conventional technology.

The fluid propulsion device 40 according to the present invention is particularly well- suited for pumping blood via an intracorporeal or extra-corporeal bridge to a transplant or a total cardiac replacement patient. When used to pump blood, the fluid propulsion device 40 desirably has a pulse flow which allows for a physiological pause at the end of a stroke.

The fluid propulsion device according to the present invention has many advantages, including very few moving parts. Unlike a conventional screw propulsion system, the fluid propulsion device 40 has no transmission parts, such as gears or a shaft, and no rotating parts.

Use of umbilical power sources allows the fluid propulsion device 40 to be freely rotated. Maneuverability of a body in an aquatic medium can be achieved by rotating the propulsion unit with respect to the axis of the umbilical power source, which provides directional thrust and steering in a horizontal plane or dive control in a vertical plane for submersibles. Moreover, the fluid propulsion device 40 can be positioned outside of the slipstream of a vessel. This implementation is particularly suited for submersibles. The ability to pulse the fluid propulsion device 40 to achieve the degree of propulsion required is also significant. The fluid propulsion device 40 may be manufactured to offer a high power-to-weight ratio. The size and lightweight, low inertia, and high efficiency use of the fluid propulsion device 40 may allow the vessel to carry an extra payload or obtain an increased range.

One alternative arrangement with respect to the present invention involves the orientation of the moveable plates that form the inner chamber, as shown in Figure 17. The embodiment 100 includes six plates 102 that overlap each other to form an alternative inner chamber 103. The plates 102 include a base member 104 and two side members, a first side member 106, and a second side memberl08. The side members, 106, 108 extend angularly from the base member 104. The plates 102 are oriented so that a first plate 110 overlaps a second plate 112 at the first side member 106 and a third plate 114 overlaps the second plate at the second side member 108. This configuration is repeated for all six plates so that there are three plates that form an inner circle. These include the second 112, fourth 116 and sixth 120 plates, which are overlapped by an outer circle formed by the first 110, third 114 and fifth 118 plates. Each plate 102 is fixed to a rod 122 that is slides within a rounded lobe hexagonal trackl23 within a drive plate 124 as previously described with respect to the first embodiment. Here, however, the drive plate 124 does not oscillate from a first to a second position, as previously described, but rotates continuously. As the rods move in the rounded lobe hexagonal track 123, they move radially inward and outward. This, in turn, results in the plates moving radially inward and outward, which results in the inner chamber 103 contracting and expanding. The inlet and outlet valves 66 function as described above. The contraction and expansion of the plates 102 that form the inner chamber 103 result in creating a propulsion force that is used to move a vessel through a body of fluid. It is understood that the embodiment 100 described immediately above forms a hexagonally shaped inner chamber 103. However, it is anticipated that a greater or lesser number of plates may be used to form differently shaped inner chambers. For example, four plates may be used to form a square shaped inner chamber. Alternatively, eight plates may be used to form an octagonally shaped inner chamber.

It should also be noted that the drive plate 124 for the alternative embodiment described above may be used in previous embodiments. The rotary action of the drive plate 124 may be used in lieu of the oscillating drive plates 47 described earlier.

As stated above, a greater or lesser number of plates may be used to form the inner chamber. As such, the angles of each side member of each plate would also change. In the embodiments described herein, six plates have been used to form a hexagonal cylindrically shaped inner chamber. As such each angle formed by the side members measures approximately 120 degrees therebetween. It is understood and appreciated that greater or fewer plates may be used to form an inner chamber. For example, eight plates may be used to form an inner chamber. In such a case each side member of a plate would measure 135 degrees therebetween.

Alternatively, five plates may be used to form an inner chamber. As such, each side member of such a plate would measure 108 degrees.

The overlap design of the inner chamber as described with respect to the second embodiment has particular application where significant power is needed. This would include certain industrial uses, particularly where slurries are involved. In such cases, large stresses may be exerted on the plates 102 that form the inner chamber. In such cases, the overlap design is preferable as the stresses on the plates may be more effectively distributed in the overlap design of the second embodiment. Moreover, the plates 102 may be reinforced on their non-sealing surface with ribbing. In particular, the plates that form the outer circle could be reinforced as needed, cantilever-style, on their upper apex and the plates that form the inner circle may be reinforced on their inner apex by an angle bracket.

Another measure that may be taken where the invention is used in power applications (such as industrial slurry applications) is to provide independent drive means for each plate. As discussed above with respect to the first embodiment, separate drive means may be used for each plate. Such means may include hydraulic or pneumatic driven actuators. Alternatively a ring motor may be used that actuates a series of cams. It is envisioned that such an arrangement could result in the actuators acting on each plate or a single action with passive return arrangement where the inner and outer plates act alternately.

A further aspect of the invention applies in cases where unidirectional flow is desired. The invention involves the elimination of the one way exhaust valves 66 from the inner and outer chamber. The function of the exhaust valve is emulated by decreasing the diameter of the exhaust port. This can be accomplished and still maintain unidirectional flow from the one way valve 66 of the inner and outer chambers by creating a cone shape 126 (as shown in Figure 18 A & B), or series of concentric tubes of decreasing outer diameter at the aft end of the device 40

(not shown). The cone shaped piece 126 is fixed to the outer housing 42. Even though the one way valve from the discharge of the inner chamber is no longer in existence and is replaced by an open port 127, the cone shaped piece 126 helps to prevent any backflow through the port. In use, when the intake valve of the inner chamber is closed, as indicated in Figure 18A with an "X", the intake valve of the outer chamber is opened and is indicated with arrows. It should be noted that the forward and aft valves of each chamber are 90 degrees out of phase with each other. For example, when the forward end of the intake valve of the inner chamber is fully open as indicated by the arrow in Figure 18B the aft end is just beginning to open. Similarly, when the forward end of the inner chamber intake valve is closed, as shown in Figure 18 A, the aft end is just starting to close. Similarly, when the forward end of the intake valve of the outer chamber is open, the aft end of the exhaust opening of the outer chamber is just beginning to open. Likewise, when the forward end of the intake valve for the outer chamber is closed, as indicated by "X'"s in Figure 18B, the aft end of the exhaust port is just beginning to close. It has been found that the length of the device 40 is preferably 1.5 times the maximum diameter of the outer housing 42.

It should be noted that a further advantage of the present invention is its ability to function as a propulsion device in extremely shallow water. It is not necessary that the device 40 be fully immersed in the fluid medium of the particular application. In a marine application, the device 40 may be built into the hull 128 of a shallow water craft 130, as shown in Figure 19. A first scoop 132 provides the inlet flow of fluid and a second scoop 134 acts as a discharge nozzle. Because the motor is a full bore type, where there is nothing to block the throat of the device and cause it to jam, it is capable of ingesting surface flotsam, solid particulate matter, such as sand and/or gravel, without damage to the device 40. In addition, because there are no moving parts external to the device, use of the device in this application minimizes any damage to marine life. Yet a further embodiment 136 of the present invention is shown schematically in Figure

20. In sum, this embodiment 136 is a plurality of the device 40 of the first embodiment placed in series. The embodiment 136 includes a first device 40 (not shown). The discharge from the inner chamber of the first unit and all subsequent units, shown by arrow A, moves via a check valve into a central pipe 138 of the embodiment 136. The central pipe 138 runs along the length of the embodiment 136. The discharge from the outer chamber of the first unit and all subsequent units, except the last unit, moves into the intake valve of the inner chamber of the next unit. For example, the discharge from the outer chamber of the first unit moves into the intake valve of the second unit. On the expansion stroke, the outer chamber pulls in fluid from the exterior housing 140 of the outer chamber 142 through gill-like slits 144. The discharge from

the inner chamber of the second and subsequent units moves as indicated by arrow B into the central pipe 138 via one-way valves. The discharge of the outer chamber of the last unit in series discharges into the body of fluid in which the embodiment is immersed, as shown by arrow C. The resulting operation of the devices in series acts to create a peristaltic effect and moves fluid along a length to increase propulsion speed without compromising sound or vibration. The overall effect of the intake valves or "gill-like" slits for the outer chamber serves to maintain the boundary flow layer close to the body of the embodiment 136. The concept underlying the series of units is to maintain a low form to drag ratio for high speed applications.

It is anticipated that there is at least on alternative configuration to the system of units in series described above and shown in Figure 20. Figure 20 shows a system of units in series where the central pipe is internally located concentrically inside the inner chamber. In an alternative configuration 169, a central conduit 172 is located externally to the units, but in fluid communication with the inner and outer chambers. As shown in Figure 21, a first arrow D in the intake flow of fluid into the intake valve for the inner chamber of the first alternate unit 170. The second arrow E indicates the intake flow into the intake valve for the outer chamber of the first alternate unit 170. For all units 160, the discharge valves of the inner chamber are in fluid communication with the central conduit 172. Similarly to the previous design, the discharge flow from the outer chamber of the first unit is in fluid communication to the intake valve of the inner chamber of the succeeding unit as indicated by arrow F. The intake valves for the outer chamber for the second and subsequent units are also the same as the previous design in that they are located on the exterior of the outer chamber and are made of one or more gill-like slits 174.

Further alterations may be made to the present invention to convert the embodiments discussed above from propulsion devices into pumps. This can be easily achieved by simply attaching tubing or piping to the intake ports and exhaust outlets of the inner and outer chambers. In one particular application of the present invention in use as a pump, the flows of the inner and outer chambers may be opposed. This may be accomplished by reversing the direction of the intake and exhaust valves of either the inner chamber or the outer chamber so that the discharge of fluid from the inner chamber has a direction opposite from the discharge of fluid from the outer chamber. Another advantage of the present invention in use as a pump, is that it is easily maintained not easily subject to damage or repair. There are no rotating parts, thus there is no risk of jamming or wear due to rotation within the pump housing. Further, because there are no parts that may seize or jam due to the type of material within the housing, there are fewer problems with wear or corrosion of parts. Because the pump is a full bore type pump, it can

handle many different types of medium through it, such as slurries, sewage, granular material, including air fluidized particular matter, as well as highly viscous materials such as molasses, molten plastics and the like.

A further improvement of the present invention over the prior art is with the addition of a removable bladder or lining within the inner and outer chambers. It is anticipated that a disposable lining or bladder may be attached to form a lining around the perimeter of both the inner and outer chambers of the present invention. As shown in Figure 22 A & B, a further alternative embodiment 146 is shown with inner 148 and outer chambers 150. The outer chamber 150 has an outer liner 152 disposed therein. The outer liner consists essentially of an elongated inner tube having an inner portion 154 and an outer portion 156 and completely enclosing the volume of the outer chamber 150 therein. The inner chamber 148 has a tubular lining 158 surrounding the outer surface 160 of the inner chamber. Both liners are pleated so that they can expand and contract without rupturing. The liners may contain a suitable lubricant on the exterior surface to aid in installation and removal. These disposable liners will enable the pump of the present invention to fully seal the inner and outer chambers. The addition of a removable and disposable bladder is particularly applicable in applications where the contents of either chamber may be toxic or hazardous or difficult to handle. These would include toxic and/or high temperature products, corrosive materials, hazardous and bio-hazardous materials, sterile products, contaminants, or sewage. It is anticipated that the liners would completely enclose the inner and outer chambers and be made of sufficiently flexible material to follow the expansions and contractions of the inner chamber 148. Moreover, the liners would be made of a sufficiently strong material to ensure that they would withstand the operational conditions and would not rupture during use. It is anticipated that such materials may include but not be limited to neoprene, rubber, high density plastic, soft plastic, or even flexible metal. A suitably flexible substrate for the liners may be coated with a appropriately resistant material depending on the fluid handled.

A pump of the present invention incorporating a lining of the inner and outer chambers as described above would have several advantages over existing prior art. First, a pump of the present invention could be used in a number of different applications where the internal surfaces of the inner and outer chambers do not need to be made of particular material to withstand exposure to certain toxic or corrosive environments. Second, because the liners are completely removable and disposable, changing over the pump's use is easy, efficient and will not result in any contamination of one product in production by another. For example, in a paint application, one color may be used and the line changed over to a different color used in the same pump with

no contamination of color in the production line. Second, the pump of the present invention may be used in a number of different applications, thus the purchase and service of the pumps can be unified and simplified rather than using specific pumps for each individual application. This saves on the purchase price as well as any repair costs or replacement parts during the course of the pump life. In addition, the liners or bladders may be switched out of a particular pump in a matter of minutes. This minimizes "down" time of the pump and the operation, as well as saves on costs and productivity.

A further advantage of the present invention used as a pump is that because it has no rotating parts, material that is moved through the pump is not macerated. This feature is particularly advantageous when using it in the area of bio-medical applications and formulations. Maceration of certain bio-medical and pharmaceutical particulate needs to be prevented in order to optimize such formulations. For example, certain pharmaceutical formulations are manufactured with the initial particulate being coated multiple times. This results in a certain extended release profile as the coating layers are digested once the drug is consumed. If the particulate coating is damaged during the manufacturing process, the body may metabolize too much of the drug particulate too quickly. This could result in the defective product causing harm to the consumer and the drug being pulled from the market at a loss to the manufacturer. Thus, the elimination of the potential for maceration of the material within the pump is a significant improvement over the prior art. Another advantage of the present invention used as a pump is that as such, its footprint is extremely small. In use as a pump, the present invention may be configured so that the size of the device for any particular application may be altered so that the device can easily be used in remote or tight fitting applications, such as in wells, etc. The design of the present pump invention is ideal for downhole applications where pumping is required. Because of the advantages over rotary pumps discussed above, the present invention can easily pass sand or shale or other abrasive materials with no damage to the pump. In addition, the internal components of the present invention can be easily and quickly changed out at low cost and to maximize productivity.

There is a further advantage to the application of the present pump invention. It is anticipated that the present pump invention may be modified to a further alternative embodiment 180 to incorporate a rotary cutter head 182 located adjacent to the intake valve 184 of the inner chamber as shown in Figure 23. When oriented vertically, this pump may be used to dredge sand, gravel, shell or other abrasive materials. It is anticipated that the outer chamber would include a filter at its intake valve so that the fluid moving therethrough included mainly smaller

particulate matter and fluid. It is further anticipated that the inner chamber would operate full bore so as to handle material with larger dimensions. It is also anticipated that the power activation means would be pneumatic and that the air discharge would be vented in such as way as to assist with the overall lift of the dredged material. A further advantage of the present pump invention is the ability to manufacture the components of the device so that they are interchangeable and easily packaged for shipment. It is anticipated that the present pump invention may be manufactured so that both the inner and outer chambers may be made of multiple components capable of remote assembly. For example, it is anticipated that the outer housing may be made into two half-shell components bolted together at the time of assembly. As a result of this interchangeable design and ease of assembly at a remote location, the present invention may be distributed in large quantities to areas in need of pumps such as disaster afflicted areas, third world countries, and any other remote or isolated area where the pumping of sewage, water, fuel or the like is needed.

A further advantage of the present pump invention is that it may be made into lengths of irrigation pipe and coupled with a solar power means for use as a solar powered irrigation system. The system could function passively to create a completely efficient irrigation network.

It should be noted that because the present pump invention has a measured stroke delineated by one way valves, it is suitable for use in the process industry where existing dosimeter pumps are used. This includes but is not limited to food processing, chemical, oil and gas, and pharmaceutical industries.

One of ordinary skill in the propulsion and pumping arts will quickly recognize that the invention has other applications in many different environments. It will also be understood by someone of ordinary skill in the art that the functionality of the present invention may vary widely. In fact, many embodiments and implementations are possible. The following claims are in no way intended to limit the scope of the invention to the specific embodiments described. In addition, the recitation "means for" is intended to evoke a means-plus-function reading of an element in a claim, whereas, any elements that do not specifically use the recitation "means for," are not intended to be read as means-plus-function elements, even if they otherwise include the word "means." It should be understood by those skilled in the art that the foregoing modifications as well as various other changes, omissions and additions may be made without parting from the spirit and scope of the present invention.