Mechanism configurable as pump or engine

Abstract

On parallel rotation axes and configured to be counter-rotating at a ratio of 2:3 are a cavity rotor including a substantially cylindrical rotor body with three evenly spaced cavities to its periphery, and a lobe rotor including a substantially cylindrical rotor body with two diametrically opposed lobes protruding from the rotor body. During a full rotation, at least portions of the rotors sweep the walls and ends of a housing enclosure, and as each lobe intersects each cavity, the two cavity apexes sweep the convex surfaces of the lobe, and between each intersect at least portions of the cavity rotor body sweep portions of the lobe rotor body.

Description

Mechanism configurable as Pump or Engine

[0001] The present invention relates generally to pumps and engines that have intermeshing rotors.

[0002] US. Pat. No 3472445 (published Oct. 1969) and GB-A-1304394 (Jan. 24, 1973) both disclose air compressors having intermeshing counter-rotating lobed rotors contained within a housing. The lobes sweep the housing wall to provide the main compression effect but a transient chamber of reducing volume is formed between the rotor lobes over part of their rotational path to exhaust the compressed charge.

[0003] GB-A-1505853 (published March 30, 1978) discloses a rotary engine having a pair of intermeshing rotors having truncated cycloidal lobes driven by intermeshing gears to compress fuel / air mixture in combustion zones form by the intermeshing rotors. The rotors are mounted on shafts that are geared together in a 1:1 speed ratio.

[0004] US. Pat. 4971002 (Nov. 20, 1990) discloses an internal combustion engine including a compressor and an expander having multi-lobed intermeshing rotors rotatably installed in a casing.

[0005] US. Pat. No 5329900 (published Jul. 10, 1994) discloses a rotary engine having separate chambers wherein each chamber has inside a rotor with three cavities intermeshing a rotor with two lobes. Each cavity has one apex where it meets the rotor body, and the apex does not sweep the convex lobe surface.

[0006] It would be useful to provide a rotary engine or equivalent pump that provides improvements over existing prior art in at least one of:efficiency;pressure output;power to weight ratio.

[0007] It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

[0008] All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinency of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

[0009] Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

[0010] In a first aspect of the present invention, there is provided a mechanism for use in a fluid pump or engine. Preferably, the mechanism includes a housing, rotatable within which are a cavity rotor and lobe rotor. Preferably, the said cavity rotor and the said lobe rotor have substantially parallel rotation axes and are configured to be counter-rotating in use, at a ratio of 2:3 rotations per cycle. Preferably, the diameter of the cavity rotor portion of the housing is approximately 1.2 times the distance between the axes of the two said rotors. Preferably the diameter of the lobe rotor portion is approximately 1.5 times the distance between the axes of the two rotors, however other ratios will work with a compromise between efficiency and robustness. Preferably the housing enclosure includes a cavity rotor portion, a lobe rotor portion and an overlapping area where the rotors intermesh. Preferably the housing enclosure includes chamber ends, wherein during rotation of the said rotors, at least portions of each cavity rotor and lobe rotor sweep the inner surface of the enclosure ends. Preferably the cavity rotor and the lobe rotor are each mounted on rotatable bearings, located in the housing end plates. Preferably the rotors may be synchronised by pinions, gears, belts or chains of other systems that are operatively connected to the rotors.

[0011] As used herein the term “cavity rotor” refers to the said cavity rotor, which preferably, includes a substantially cylindrical rotor body with three identical cavities in the entire length of the rotor body, the said three cavities extending transversely to a rotation axis of the cavity rotor and evenly spaced about a periphery of the cavity rotor transverse to the cavity rotor axis. As used herein the term “cavity” refers to a cavity in the cavity rotor, which preferably, includes a substantially concave cavity surface meeting each outer rotor surface, the two said substantially concave cavity surfaces may also meet each other toward the back of the cavity or alternatively may be separated by another shaped surface such as convex or flat. At the junctions of the cavity surface and the outer body surfaces are six apexes. As used herein the term “cavity forward apex” refers to a junction of the cavity surface and the rotor body outer surface that faces the direction of rotation of the cavity rotor. As used herein the term “cavity rear apex” refers to the apex that faces opposite the direction of rotation, Preferably, the cavities may be minimally sized for the lobe rotor to sweep in some embodiments, such as a pump or a compressed air or steam engine, or in other embodiments, such as combustion engines, the cavities may have greater depth and intricate shape in order for the engine to achieve the desired compression ratio and burn pattern. Preferably, the curved outer surfaces extending between the cavities are substantially concentric with the axis of rotation of the cavity rotor and of similar diameter to the corresponding section of the housing. Preferably at least portions of the cavity rotor body outer surface are configured to sweep an inner surface of the cavity rotor chamber during use.

[0012] As used herein the term “lobe rotor” refers to the said lobe rotor, which preferably, includes a substantially cylindrical rotor body with two diametrically opposed lobes protruding from the entire length of the rotor body and extending transversely to a rotation axis of the lobe rotor. As used herein the term “lobe” refers to a lobe of the lobe rotor, which preferably, includes a leading convex surface, an outer lobe surface, and a trailing convex surface. Preferably, each convex leading and trailing surface meets at an apex with the outer surface of the lobe. Preferably, the outer surface of the lobe may be minimal such that the two convex lobe surfaces meet the outer surface at a common point, or the outer surface may be substantially concentric with the axis of rotation of the lobe rotor. Preferably the outer surface is configured to sweep an inner surface of the corresponding lobe rotor chamber during use.

[0013] Preferably, during rotation of the lobe rotor and the cavity rotor, in the space where the rotors intermesh, a lobe intersects a cavity, and a cavity rear apex sweeps a said leading convex surface of the lobe rotor, and a cavity forward apex sweeps a said trailing convex surface of the lobe rotor. Preferably, as the said rotation continues, the cavity forward apex sweeps to the inner end of a said trailing convex surface, at which time at least portions of the said cavity rotor outer body surface sweep at least portions of the said lobe rotor body surface until the next cavity is intersected by the next lobe. Preferably, a full cycle of the said mechanism includes two rotations of the cavity rotor, such that each cavity has been intersected by each lobe, and the rotors have returned to the starting position.

[0014] Preferably, during the use of the mechanism, as the said rotors turn, one lobe is travelling towards the next cavity intersect, and one lobe is travelling away from the previous cavity intersect. The volume of the empty space in front of the leading surface of the lobe that is travelling towards a cavity intersect reduces until the middle of the lobe has rotated into the middle of the cavity. As used herein the term “reduction chamber” refers to this reducing space. As a lobe travels away from a cavity intersect the volume of empty space between the cavity and the lobe trailing surface increases. As used herein the term “expansion chamber” refers to this increasing space.

[0015] Preferably, the mechanism includes at least one inlet port and one outlet port, formed in the housing wall or end plates. Depending on the mechanisms embodiment, the ports may open and close as the rotors cover and uncover the openings, or alternatively the ports may be controlled by other means such as valves or injection ports. The said inlet and outlet ports need to be located to suit the embodiment of the mechanism, a pump will require different port configurations to an engine. Some embodiments may require multiple ports, such as inside the rotor intersecting area, and outside the rotor intersecting area of both the reduction and expansion chambers.

[0016] A preferred embodiment of the mechanism may be used in pumping applications, this configuration has the inlet port(s) located in the expansion chamber, and the outlet port(s) are located in the reduction chamber. During use, inlet port(s) into the increasing space of the expansion chamber allows fluid to be drawn into the mechanism, and then by the rotation of the lobe rotor, the fluid is transferred to the reduction chamber, where outlet port(s) allows the fluid to escape the decreasing space. The location of the outlet port(s) can affect the pressure of the fluid exiting the device. For example a large port can be located outside the rotor intersecting area of the reduction chamber to allow the fluid to escape at lower pressure, compared to having only a port inside the intersecting area of the reduction chamber which would cause the fluid to be compressed inside the reduction chamber, until the rotating rotors expose the higher pressure outlet port.

[0017] A preferred embodiment of the mechanism may be included in a pumping configuration that provides both higher and lower pressure fluid output, by including independently controllable outlet ports. Such an example could be used to create a supercharger for a vehicle that doubles as a compressor to capture existing kinetic energy, for example during braking. Under regular operation of the vehicle the larger low pressure port is open delivering air to the engine, however during regenerative braking only the smaller higher pressure port is open, in order to compress the air, and then force it out of the device at higher pressure and into a tank for future uses, such as immediate engine boost, engine start, or to run air driven accessories for examples.

[0018] Another preferred embodiment of the mechanism is for inclusion in a fluid pressure driven engine configuration. In such an example high pressure fluid such as compressed gas or steam is introduced at the inlet port(s) into the expansion chamber, pushing between the cavity rotor surfaces and trailing lobe surface, generating rotational power as the expansion chamber is pressured to increase in size to accommodate the increased fluid volume. Preferably inlet ports would be located both inside and outside of the rotor intersecting area of the reduction chamber.

[0019] Other preferred embodiments of the mechanism are for inclusion in internal combustion engine configurations. Preferably, during the mechanism cycle, each time a lobe passes through the middle of a cavity compressed air and fuel are ignited. The explosion creates pressure on the lobe trailing surface, pushing it out of the cavity and away from the cavity rotor. The expanding gases remain trapped within the expansion chamber until the expansion area increases to its maximum size, at which time the outlet port opens.

[0020] A preferred embodiment of the mechanism may be included in an internal combustion engine that is naturally aspirated. Preferably, the explosion and power stroke utilize part of the expansion chamber, including the rotor intersect area, and the second part of the expansion chamber is used to draw air into the mechanism. Preferably, as a lobe rotates into the reduction chamber, prior to reaching the rotor intersect area, it compresses the air in front of the leading lobe surface to 2:1 ratio, at which time an alignment of the two rotors simultaneously opens two passageways. One passageway allows some of the compressed air to push through a notch between the rotors into the chamber space in front, wherein the expansion of the exploded gases has occurred and an outlet port is open, and a second passageway allows the compressed air to push into the approaching cavity, wherein another exhaust port is open. Preferably, the rush of incoming air pushes the expanded gases through the open exhaust outlet ports. Preferably the ports will then close and the lobe will continue to travel towards the approaching cavity. Preferably fuel is then injected and mixes with the compressing air, and the mixture is pushed into the back of the cavity by the intermeshing lobe, wherein the mixture is ignited and the cycle continues.

[0021] Another preferred embodiment may include the naturally aspirated embodiment described above with the further addition of an identical second lobe rotor and apparatus located adjacent to the cavity rotor diametrically opposite the first lobe rotor, such that a second reduction and expansion chamber is formed, thus doubling the engine capacity.

[0022] A preferred embodiment of the mechanism may be configured for forced air aspiration. Preferably, the combustion and power stroke utilize as much of the expansion chamber as possible. Preferably Inlet and outlet ports are located to facilitate a supercharger or other forced air device that provides pressurized air to clear spent exhaust gases from the engine mechanism while reloading the reduction chamber. A preferred embodiment may include active gateways between a portion of the cavity rotor and the adjacent housing in order to allow combustion gases contained in the cavity to continue to expand into the expansion chamber after the cavity has rotated to align with the cavity rotor housing surface portion.

[0023] The gateway may be created by a section of the housing moving, or alternatively by a section of the cavity rotor moving, preferably, controlled by interaction with the lobe rotor. Alternatively a passageway through the housing from the cavity rotor portion to the lobe rotor portion will also allow the pressurized gases in the cavity to continue to pass into the expansion chamber. Similar gateways or passageways may be included between the reduction chamber and approaching cavity to facilitate the cavity to be cleared of exhaust gases and reloaded with air.

[0024] Another preferred embodiment may include features of the forced air embodiment described above, without the supercharger, but with the further addition of a third rotor and associated apparatus that is used to draw air into the mechanism, and deliver it to the reduction chamber. The additional rotor may be either cavity or lobe depending on configuration. Such configurations may have asymmetrical reduction and expansion chambers, which may improve engine efficiency by expanding the explosive pressure to a greater volume before it is expelled from the mechanism.

[0025] Another preferred embodiment of the mechanism may include configuration wherein the outer apexes of each lobe sweep the inner surfaces of each cavity, which results in the cavity being divided into two portions as the lobe passes through it. As used herein the term “leading cavity portion” refers to the area between the leading convex lobe surface and the concave cavity surface that extends from the trailing cavity apex to where it is being swept by the outer lobe surface. As used herein the term “trailing cavity portion” refers to the area between the trailing convex lobe surface and the concave cavity surface that extends from the leading cavity apex to where it is being swept by the outer lobe surface. Preferably during operation, as each lobe passes through each cavity, a suitable amount of high pressure air to achieve the desired compression ratio is injected directly into the trailing cavity portion, wherein preferably, high pressure fuel injection occurs simultaneously either premixed with the air or by way of separate injector, and the mixture is ignited. Preferably, such an embodiment may also include variable injection timing, such that the combustion zone is at its smallest size prior to the lobe reaching the middle of the cavity, and gets bigger as the lobe progresses. Early injection into the smaller chamber would require less air and fuel to achieve the desired compression rate, and would allow the combustion gases to have an expansion ratio much higher than the compression ratio, a desirable characteristic for efficiency. Whereas delayed injection would require more fuel and air and would result in lower expansion ratios. Such an embodiment would be suitable for a variable workloads, utilizing the delayed injection and larger chamber under heavy workload, and the early injection and smaller chamber being utilized under light workload.

[0026] Preferably, in some embodiments each cavity and lobe rotor may be composed of several attached parts, such as a hub with hinged rotor sectors that can contact the chamber walls, to enable active sealing of the chamber. The hinged rotor sectors may also automatically open and close gateways between the rotors and the housing during the engine cycle. Preferably the hinged rotor sectors may be balanced to centrifugal energy to limit the amount of friction occurring between contacting component surfaces. Alternatively the hinged rotor sectors may also retract the contact points to a fine clearance at high RPM, in order to reduce friction at a time when air has less time to escape. Preferably material more suitable for mechanical seals than that which the rotor components are constructed from, can also be provided at the tip and / or ends of the rotor sectors.

[0027] The preferred embodiments for use in internal combustion engines may be configured for operation with any suitable combustible fuel such as hydrogen, petrol, diesel, or biofuel, for example. Preferably, the fuel may be injected directly into the combustion chamber, alternatively it may be premixed with the air supply.

[0028] Preferably, ignition may occur due to compression, or alternatively due to spark ignition from sparkplugs or other suitable components.

[0029] Preferably the motive output from an engine embodiment may be taken from any of the rotating shafts, or alternatively output from the engine may be taken from the flow into or out of the engine.

[0030] Preferably, an engine embodiment may use the flow of air to cool the components. Alternatively, the engine may use liquid coolants to control the temperature of the components.

[0031] Preferably, the engine may be started by injecting compressed air into the decompression phase of the combustion chamber. Alternatively a starter motor may be required.

[0032] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.

[0033] Reference herein is made to various aspects and embodiments of the present invention. For clarity and to aid prolixity every possible combination, iteration or permutation of features, aspects and embodiments are not described explicitly. Thus, it should be appreciated that the disclosure herein includes any combination, iteration, multiple or permutation unless explicitly and specifically excluded.

[0034] The order in which aspects, embodiments, features or descriptions occur in this description should not be interpreted to necessarily require the preceding aspects, embodiments, features or descriptions.

[0035] Reference throughout this specification to the singular should be interpreted to include the plural and vice versa unless specifically stated otherwise.

[0036] The invention consists in the foregoing and also envisages constructions of which the following gives examples only.

[0037] Although specific advantages have been enumerated above, various embodiments may include some, none, or all of the enumerated advantages.

[0038] Other technical advantages may become readily apparent to one of ordinary skill in the art after review of the following figures and description.

[0039] It should be understood at the outset that, although exemplary embodiments are illustrated in the figures and described below, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should in no way be limited to the exemplary implementations and techniques illustrated in the drawings and described below.

[0040] Unless otherwise specifically noted, articles depicted in the drawings are not necessarily drawn to scale.

[0041] Modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein without departing from the scope of the disclosure. For example, the components of the systems and apparatuses may be integrated or separated. Moreover, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components and the methods described may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. As used in this document, “each” refers to each member of a set or each member of a subset of a set.

[0042] Unless otherwise specified, it should be appreciated that references to directions in the following description such as side, above or below are for reference only, and should not be considered limiting.

[0043] The present invention will now be described with reference to the accompanying drawings in which Figures 1 to 23 are schematics of preferred embodiments of the Mechanism.

[0044] shows a mechanism according to one embodiment, and is shown without ports

[0045] shows a mechanism according to a second embodiment, and is configured as a pump or supercharger.

[0046] shows a mechanism according to a second embodiment, and is configured as a pump or supercharger in compressor mode.

[0047] shows a mechanism according to a second embodiment, and is configured as a pump or supercharger in compressor mode.

[0048] shows a mechanism according to a third embodiment, and is configured as a naturally aspirated internal combustion engine.

[0049] shows a mechanism according to a third embodiment, and is configured as a naturally aspirated internal combustion engine.

[0050] shows a mechanism according to a third embodiment, and is configured as a naturally aspirated internal combustion engine.

[0051] shows a mechanism according to a third embodiment, and is configured as a naturally aspirated internal combustion engine.

[0052] shows a mechanism according to a forth embodiment, and is configured as a naturally aspirated internal combustion engine including the addition of a 2ndidentical lobe rotor and associated components that create a 2ndcombustion chamber within an enlarged housing.

[0053] Figures 10 shows a mechanism according to a fifth embodiment and is configured as an internal combustion engine that requires a supercharger or other forced air system to operate, the rotors are divided into further parts including hubs with hinged segments that interact with each other and the housing wall to open passages between the cavities and the lobe rotor air space.

[0054] Figures 11 shows a mechanism according to a fifth embodiment as an internal combustion engine.

[0055] Figures 12 shows a mechanism according to a fifth embodiment as an internal combustion engine.

[0056] Figures 13 shows a mechanism according to a fifth embodiment as an internal combustion engine.

[0057] Figures 14 shows a mechanism according to sixth embodiment and is configured as an internal combustion engine that requires a supercharger or other forced air system to operate, the housing has two hinged portions that are synchronised to open and close during the cycle, to open passages between the cavities and the lobe rotor air space.

[0058] Figures 15 shows a mechanism according to sixth embodiment and is configured as an internal combustion engine.

[0059] Figures 16 shows a mechanism according to sixth embodiment and is configured as an internal combustion engine..

[0060] Figures 17 shows a mechanism according to sixth embodiment and is configured as an internal combustion engine.

[0061] Figures 18 shows a mechanism according to seventh embodiment, and is configured as a naturally aspirated internal combustion engine, an additional cavity rotor and other components are added that bring together features of the supercharger in Figures 2 to 4 and the engine of Figures 14 to 17 within the same housing.

[0062] Figures 19 shows a mechanism according to seventh embodiment, and is configured as a naturally aspirated internal combustion engine.

[0063] Figures 20 shows a mechanism according to seventh embodiment, and is configured as a naturally aspirated internal combustion engine.

[0064] shows a mechanism according to eighth embodiment, and configuration is a similar engine design to Figures 18 to 20 wherein the rotors are split into further parts including hubs with hinged segments that interact with each other and the housing wall, in order to seal the combustion chamber, reduction and expansion areas.

[0065] shows a mechanism according to ninth embodiment, and is configured as a naturally aspirated internal combustion engine, an additional lobe rotor and other components are added that bring together features of the supercharger in Figures 2 to 4 and the engine of Figures 14 to 17 within the same housing.

[0066] Figures 23 shows a mechanism according to 10th embodiment, and is configured as an internal combustion engine with two combustion zones, and includes high pressure air and high pressure fuel injected directly into the combustion areas immediately prior to ignition.

[0067] Referring to, a mechanism 1 suitable for configuration as an engine or pump is shown. Rotatable within a housing 41 are a cavity rotor 40 and a lobe rotor 48. The cavity rotor 40 rotates anticlockwise, it includes a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it is a substantially cylindrical rotor body 3 with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing convex surface 73a, 73b, which each meet the rotor body 3 at close to perpendicular angle. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotor 48. As the rotors rotate the space 44 grows in size (expansion chamber), the growing volume can be used to harness the energy of expanding combustion gases, or alternatively a port (not shown) can be included that will allow gases or liquids to be drawn into the device. Meanwhile the area 49 reduces in size (reduction chamber), the contents are then pushed into the cavity 42b, or alternatively a port or ports (not shown) can allow the contents to escape the mechanism.

[0068] shows the inventive mechanism configured as an air pump or supercharger. Rotatable within a housing 41 are a cavity rotor 40 and a lobe rotor 48. The cavity rotor 40 rotates anticlockwise, it includes a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it is a substantially cylindrical rotor body 3 with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotor 48. As the rotors 40 and 48 rotate the expansion chamber 44 increases in size causing air to be drawn in through the large inlet port 45. Meanwhile on the opposite side of the lobe rotor 48 the reduction chamber 49 is shrinking in size, causing the air to be pushed into the large outlet port 68. Meanwhile the air space in the cavity 42b is also shrinking as the lobe 47 intersects, pushing air into the small outlet port 50.

[0069] shows the pump or supercharger ofin compressor / regenerative braking mode. The reduction chamber 49 is reducing in size as the lobe 47 rotates towards the cavity 42b, the large outlet port 68 is closed causing the air pressure to increase.

[0070] also shows the pump or supercharger ofin compressor / regenerative braking mode. The reduction chamber 49 is now contained within the cavity 42b. The small outlet port 50 is open, allowing the substantially pressurized air to escape the mechanism.

[0071] shows an example of how the mechanism can be configured as a naturally aspirated internal combustion engine 1. Rotatable within a housing 41 are a cavity rotor 40 and a lobe rotor 48. The cavity rotor 40 rotates anticlockwise, it includes a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it is a substantially cylindrical rotor body 3 with two diametrically opposed notches 72a, 72b and two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotor 48. The outlet port 65 is closed by the rotating valve 67. As the rotors 40 and 48 rotate the expansion chamber 44 increases in size, causing air to be drawn in through the inlet port 63. On the opposite side of the lobe rotor 48 the reduction chamber 49 is shrinking in size, causing the air pressure to increase. The cavity 42b is intermeshed by the lobe 47, and the compressed air and fuel mixture within has been ignited.

[0072] shows the engine ofafter further advanced rotation. The outlet port 65 remains closed by the outlet valve 67. The expansion chamber 44 has increased in size as the combustion pressure has effect. The intermediate chamber 43 contains a charge of air, ready for the next sequence. The reduction chamber 49 contains air under increasing pressure. The cavity 42c contains combustion gases that are still under considerable pressure. The cavity 62a also contains exhaust gases, however, the cavity rotor 40 has rotated to expose the outlet port 64 and much of the pressure has been relieved as the gases are able to escape.

[0073] shows the engine of Figures 5 and 6 after further advanced rotation. Simultaneously, the rear cavity 70a has rotated clear of the housing 41 and opened the cavity 42a to the reduction chamber 49, and the lobe rotor 48 has rotated to align the notch 72a with the cavity rotor 40 thus opening a passageway between the two rotors. The pressurized air contained in the reduction chamber 49 is simultaneously released into the cavity 42a where it flushes remaining exhaust gases through the outlet port 64, and the expansion chamber 44 where it flushes the exhaust gases through the outlet 65 via the exhaust valve 67 and exit passage 66.

[0074] shows the engine of Figures 5 to 7 after further advanced rotation. The exhaust valve 67 is closed and the expansion chamber 44 contains flushed air. The holding chamber 43 contains a charge of air for the next sequence. The reduction chamber 49 including the cavity 42a, contains the air for the next combustion event, and the fuel 60 has been introduced. The cavities 42b, 42c contain exhaust gases.

[0075] shows an engine mechanism similar to the engine of figures 5 to 8, as shown in, but with the addition of a 2ndidentical lobe rotor 76 and associated valve 79 and passageways 73, 78, 80, 81, 82. This forms a 2ndcombustion chamber 42c on the left side of the cavity rotor within an enlarged housing 41, wherein ignition has just occurred. A second reduction chamber 75 contains air that is starting to be compressed, and the expansion chamber 77 is also filled with air and is still drawing air through the port 78.

[0076] shows an example of how the mechanism can be configured as an internal combustion engine. The engine 1 includes a housing 41 defining a chamber rotatable within which are a cavity rotor 40 and a lobe rotor 48. The cavity rotor 40 rotates anticlockwise, it includes a hub 11 with three outer segments 13a, 13b, 13c attached via pivot pins 12a, 12b, 12c, and intersegment seals 14a, 14b, 14c which together form a cylinder with three evenly spaced cavities 42a, 42b, 42c and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it includes a hub 10 with leading sections 23a, 23b and trailing sections 22a, 22b connected to it which combine to substantially form a cylinder with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. Ideally the lobe rotor sections 22a, 22b, 23a, 23b are balanced and are spring loaded as indicated by the direction arrows. The cavities 42a, 42b, 42c are configured to interact with the lobes 46, 47 of the intake rotor to define a combustion chamber. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotor 48.

[0077] Air with boosted pressure is allowed into the engine 1 through the inlet port 5 via the synchronized rotating valve 6, and also, when each cavity 42a, 42b, 42c aligns to allow it, through the inlet port 16.

[0078] Exhaust gases exit the engine 1 through the outlet port 15 as each cavity 42a, 42b, 42c aligns to allow it, and through the opening 29 via rotating valve 8, to initially the turbo port 7(goes to turbo), and then the exhaust flushing port 9.

[0079] With reference to, the cavity 42a is releasing exhaust gas pressure through the outlet port 15. Cavity 42c contains decompressing combustion gases from the most recent combustion event. The intermediate chamber 43 contains partially decompressed combustion gases that are about to be sent to the turbo port 7. The reduction chamber 49 is shrinking, and as the cavity rotor segment 13b interacts with the lobe rotor hub 10, a passageway 4 is opening between the housing 41 and the rotor segment 13b allowing the air to move into the cavity 42b.

[0080] shows the engine mechanism ofafter further advanced rotation. The cavity 42a is aligned with the inlet port 16 and the outlet port 15 allowing the cavity to be flushed out by air with boosted pressure. The cavity 42c contains expanding combustion gases which are able to flow through the passageway 18 into the expansion chamber 44. The intermediate chamber 43 contains the remaining exhaust gases from the previous combustion event which did not go to the turbo port 7, the rotating exhaust valve 8 is opening the outlet 29 to the turbo bypass port 9, and with the inlet valve 6 open, pressurized air from the turbo or supercharger is flowing in, and is flushing the exhaust gas out. The reduction chamber 49 is shrinking, it contains air with increasing pressure that is being forced through the passageway 4 into the cavity 42b.

[0081] shows the engine mechanism of Figures 10 and 11 after further advanced rotation. The cavity 42a contains clear air that is reaching boost pressure. The cavity 42c contains expanding combustion gases which are continuing to flow through the passageway 18 into the expansion chamber 44. The exhaust valve 8 is now closed and the intermediate chamber 43 is filled with clean air that is filling with boost pressure. The air in the reduction chamber 49 is being compressed into the cavity 42b.

[0082] shows the engine mechanism of Figures 10-12 after further advanced rotation. The cavity 42b contains air with boosted pressure. Combustion gases continue to push from the cavity 42c through the passage 18 into the growing expansion chamber 44. The reduction chamber 49 is shrinking in size, it contains air with boosted pressure that is now being compressed. The cavity 42a contains compressed air mixed with fuel and ignition is happening.

[0083] Figures 14 shows an example of how the mechanism can be configured as an internal combustion engine. The engine 1 includes a housing 41 defining a chamber, rotatable within which are a cavity rotor 40 and a lobe rotor 48. The cavity rotor 40 rotates anticlockwise, and has a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it is a substantially cylindrical rotor body 3 with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotor 48. The expansion gate 85 and compression gate 87 are synchronized to open and close during the engine cycle.shows the expansion gate 85 open, the combustion gases are decompressing from the cavity 42a through the passage 96 into the expansion chamber 44. The holding chamber 43 is being flushed out through the outlet 93 as air with boosted pressure floods into the inlet 89. The cavity 42c contains compressed air mixed with fuel, the compression gate 87 is closed. The cavity 42b contains exhaust gas which has decompressed through the outlet port 86.

[0084] shows the engine mechanism ofafter further advanced rotation. The expansion gate 85 open, the combustion gases are further decompressing from the cavity 42a through the passage 96 into the expansion chamber 44. The outlet port 93 remains closed. The intermediate chamber 43 contains air with boosted pressure, the inlet 89 is open allowing air to continue to enter, and with the compression gate 87 open, the air travels through the passage 97 into the cavity 42b, flushing exhaust gases into the outlet port 86. The cavity 42c contains air mixed with fuel that has been compressed within the reduction chamber 49, which is currently entirely contained within the cavity 42c, approaching the ignition phase.

[0085] shows the engine mechanism of Figures 14 and 15 after further advanced rotation. The expansion gate 85 is open, the combustion gases are further decompressing from the cavity 42a through the passage 96 into the expansion chamber 44. The outlet port 93 is closed. The reduction chamber 49 including the cavity 42b contain air with boosted pressure, the inlet port 89 is closed. The compression gate 87 is open allowing air to move from the shrinking space 88 through the passage 97 into the cavity 42b. In the cavity 42c ignition is occurring.

[0086] shows the engine mechanism of Figures 14 -16 after further advanced rotation. The expansion gate 85 is almost closed, the cavity 42a and expansion chamber 44 both contain expanded gases and are about to be isolated from each other as the passage 96 closes. The outlet port 93 is about to open. The compression gate 87 remains open allowing air to move from the shrinking reduction chamber 49 through the passage 97 into the cavity 42b. The cavity 42c contains expanding combustion gases.

[0087] shows an example of how the mechanism can be configured as an internal combustion engine. The engine 1 includes a housing 41 defining a chamber, rotatable within which are two cavity rotors 40, 120 and a lobe rotor 48. A first cavity rotor 40 rotates anticlockwise, and has a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a substantially concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it has a substantially cylindrical rotor body 3 with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. A second cavity rotor 120 rotates anticlockwise, and has a substantially cylindrical rotor body 17 with 3 evenly spaced cavities 112a, 112b, 112c, each with a passage 108a, 108b, 108c to the outer rotor body 17. The ratio is two rotations of the cavity rotors 40, 120 to three rotations of the lobe rotor 48. The surfaces of the rotors are shaped so that as one of the lobes passes through a corresponding cavity, the tips of the cavity sweeps the surfaces of the lobe. Mounted from the housing are synchronized exhaust valve 110, intake valve 106, and expansion gate 85 which is controlled by a cam 118.shows the expansion gate 85 open allowing combustion gases to pass from the cavity 42c through the passage 96 into the expansion chamber 44. The rotating exhaust valve 110 is closed. The cavity 112c of the second cavity rotor 120 is reducing in size as the lobe 46 enters, the air contained is being pushed through the passage 108c into the reduction chamber 49, this puts pressure on the air within, which causes it to be pushed into the passage 119 past the open valve 106 and further passage 104 arriving at the cavity 42b where it flushes exhaust gas through the outlet port 103. The other two cavities 112b and 112a of the second cavity rotor 120 also contain clean air. The cavity 42a contains compressed air and fuel that is being ignited.

[0088] Figure 19 shows the cavity 42c containing exhaust gases, now isolated from the expansion chamber 44 due to the gate 85 closing. The exhaust valve 110 has opened allowing the exhaust gases in the space 114 to begin exiting through the outlet ports 111 and 109. The cavities 112a, 112b, 112c, 42b and reduction chamber 49 contain clean air. The cavity 42a contains expanding combustion gases.

[0089] shows the cavity 42c containing exhaust gases. The combustion gases in the cavity 42a are expanding into the expansion chamber 44. The shrinking space 142 is expelling exhaust gases through the passages 111 and 109 as the exhaust valve 110 is open. The cavities 112b and 112a contain air, and the cavity 112c is drawing air into the engine through the inlet port 121. The reduction chamber 49 and the cavity 42b contain air that is being compressed, fuel 60 is being injected.

[0090] shows the engine of Figures 18 to 20 with modification of the cavity rotor 40 to be compiled of a hub 11, pivoting rotor segments 13a, 13b, 13c, and intersegment seals 14a, 14b 14c. Each cavity rotor segment is spring loaded towards the housing wall, and is designed to allow the compressed gas push between the rotor segments in order to put pressure on the sealing surface. For example between the cavity rotor segments 13c and 13a is a passage 140c ending at the intersegment seal 14a, pushing each seal 13c, 13a towards the housing wall. The lobe rotor 48 is compiled of a hub 10 and pivoting rotor segments 22a, 22b, 23a, 23b, each spring loaded towards the housing wall, and is designed to allow the compressed gas to get between the rotor segment and the lobe rotor hub 10 in order to put pressure on the sealing surface. For example between the cavity rotor segments 13c and 13a is a passage 140c ending at the intersegment seal 14a, pushing each seal 13c, 13a towards the housing wall. The expanding combustion gases in the cavity 42a are moving through the open gate 85 and passage 96 into the expansion chamber 44. The space 114 is shrinking and the exhaust gases within are being pushed through the passages 111, 109 and open exhaust valve 110. The pocket of air in the cavity 112b is helping to force the gas out. A turbo charger (not shown) may be ideal for increasing the size of the air pocket which the exhaust gases push against during this part of the cycle. The cavities 112a 112b are filled with air and the growing space 105 will continue to draw air into the engine through the inlet port 21 via the passages 107, 119 and control valve 106. In the cavity 102b a mixture of air and fuel is being compressed.

[0091] shows a naturally aspirated internal combustion engine. The engine 1 includes a housing 41 defining a chamber, rotatable within which a cavity rotor 40, and two lobe rotors 140, 48. The cavity rotor 40 rotates anticlockwise, it includes a hub 11 with three outer segments 13a, 13b, 13c attached, and intersegment seals 14a, 14b, 14c which together form a cylinder with three evenly spaced cavities 42a, 42b, 42c and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotor 48 rotates clockwise, it includes a hub 10 with leading sections 23a, 23b and trailing sections 22a, 22b connected to it, which combine to substantially form a cylinder with two diametrically opposed lobes 46, 47 protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. Ideally the lobe rotor sections 22a, 22b, 23a, 23b are balanced and are spring loaded towards the housing 41. A second lobe rotor 140 rotates clockwise, and has a substantially cylindrical rotor body 150 with two diametrically opposed lobes 151, 152 protruding from it. Each lobe has a leading convex surface 153a, 153b, and a trailing surface 154a, 154b. The ratio is two rotations of the cavity rotor 40, to three rotations of the lobe rotors 48, 140. The surfaces of the rotors are shaped so that as one of the lobes passes through a corresponding cavity, the tips of the cavity sweeps the surfaces of the lobe. Mounted from the housing are synchronized valves 67, 148 and expansion gate 85 which is controlled by a cam 118.depicts air being drawn into the growing space 164 below the lobe rotor 150 through the inlet port 142. In the chamber area 141 ahead of the lobe 152 is a charge of fresh air. The lobe rotor 150 has just stopped sending air through the passage 162, and is now heading into the cavity 42a, which currently contains expanded combustion gases from the second most recent ignition event that are being pushed out a small outlet port 166. In the cavity 42c and the expansion chamber 44 are expanding combustion gases from the most recent ignition event, the expansion gate 85 has opened to allow the cavity 42c to remain connected to the expansion chamber 44. The exhaust valve 67 has rotated to block the outlet 65, likewise the inlet passage 149 is closed by the valve 148, as the intermediate chamber 43 has just been flushed out and readied for the next compression event. Fuel 167 is being added to the compressing air in the reduction chamber 49 including the cavity 42b.

[0092] Figures 23 shows another configuration of the inventive mechanism as an internal combustion engine, wherein from a tank the required amount of pre-compressed air to achieve the desired compression ratio and fuel are injected directly into the combustion chamber and immediately ignited. Rotatable within a housing 41 are a cavity rotor 40 and two lobe rotors 48a, 48b. The cavity rotor 40 rotates anticlockwise, it has a substantially cylindrical rotor body 2 with three evenly spaced cavities 42a, 42b, 42c, and each cavity has two apexes where a concave surface of the cavity meets the outer cylinder wall, the forward facing apexes 69a, 69b, 69c, and the rearward facing apexes 70a, 70b, 70c. The lobe rotors 48a, 48b rotate clockwise, they each have a substantially cylindrical rotor body 3 with two diametrically opposed lobes 46a, 46b, 47a, 47b protruding from it. Each lobe has a leading convex surface 71a, 71b, and a trailing surface 73a, 73b. The ratio is two rotations of the cavity rotor 40 to three rotations of the lobe rotors 48a, 48b. Expansion gates 85a, 85b are synchronized to open and close during the engine cycle.depicts the engine in operation. The reduction chamber 49a is pushing exhaust gases from the fifth most recent combustion event through the outlet 207. The lobe 47a has divided cavity 42b into two parts 42ba, 42bb wherein a combination of compressed fuel and air that is about to be injected and ignited. The expansion chamber 44b including the cavity 42a contains expanding gases from the most recent combustion event. The intermediate chamber 43 has expanding gases from the third most recent combustion event. The reduction chamber 49b including cavity 42c contains expanded gases from the fourth most recent combustion event that are being expelled through the exhaust port outlets 204, 205. The expansion chamber 44a contains expanding gases from the second most recent combustion event.

Claims

A mechanism for use in a fluid pump or engine, the mechanism including:at least a housing;at least a first rotatable lobe rotor located in a corresponding lobe rotor chamber of the housing, the lobe rotor including a rotor body and two diametrically opposed lobes protruding from the rotor body and extending transversely to a rotation axis of the lobe rotor, the two lobes including a leading convex surface, a trailing convex surface, and an outer lobe surface, the outer surface configured to sweep an inner surface of the corresponding lobe rotor chamber during use;at least a first cavity rotor located in a corresponding cavity rotor chamber of the housing, the cavity rotor including a substantially cylindrical rotor body with three cavities in the rotor body, the three said cavities extending transversely to a rotation axis of the cavity rotor and evenly spaced about a periphery of the cavity rotor transverse to the cavity rotor axis, the junctions of each cavity surface and the rotor body outer surface creating a forward apex that faces the direction of rotation of the said cavity rotor, and a rear apex that faces opposite the direction of rotation, wherein portions of the rotor body are configured to sweep an inner surface of the cavity rotor chamber in use;at least one inlet port, andat least one outlet port,wherein the cavity rotor chamber and lobe rotor chamber are conjoined such that the housing includes a cavity rotor area, a lobe rotor area and an overlapping area where the rotors intersect, andwherein the housing enclosure includes chamber ends, and at least portions of each lobe rotor and cavity rotor sweep the chamber ends, andwherein the said first lobe rotor and the said first cavity rotor have substantially parallel rotation axes and are configured to be counter-rotating in use, andwherein the cavity rotor and lobe rotor rotate in use at a ratio of 2:3 rotations per cycle. andwherein during rotation of the lobe rotor and the cavity rotor, a said lobe intersects a said cavity of the cavity rotor, and at least the rearward facing apex of the cavity sweeps the leading convex surface of the lobe, and the forward facing apex of the cavity sweeps the trailing convex surface of the lobe, and between each cavity intersect at least portions of the cavity rotor body sweep portions of the lobe rotor body.The mechanism as claimed in claim 1, wherein the cavities of the cavity rotor include a forward concave surface that faces the direction of rotation of the cavity rotor, and a rearward concave surface that faces opposite the direction of rotation of the cavity rotor, wherein the lobe rotor and cavity rotor are shaped such that in use as an outer lobe surface sweeps the into the middle of the cavity, then the said cavity is temporarily divided into a cavity leading portion defined by the said cavity rearward concave surface and a lobe leading convex surface, and a cavity trailing portion defined by the said cavity forward surface and intersecting lobe trailing convex surface.The mechanism of any one of the preceding claims, wherein the distance between the cavity rotor and lobe rotor rotation axes is approximately 1.25 times the diameter of the lobe rotor body, adjacent a said lobe.The mechanism of any one of the preceding claims, wherein a diameter of the cavity rotor is approximately 1.2 times the distance between the cavity rotor and lobe rotor rotation axes.The mechanism of any one of the preceding claims, wherein the inlet and outlet port(s) are located to permit fluid to enter the housing, and exit the housing, wherein the ports are controllable to selectively permit passage of fluid there through.The mechanism as claimed in any one of the preceding claims, further including a second lobe rotor and corresponding lobe rotor chamber located on an opposing side of the cavity rotor, wherein the first lobe rotor and second lobe rotor are synchronised for rotation in the same direction and speed.The mechanism as claimed in any one of the preceding claims, further including a second cavity rotor and corresponding cavity rotor chamber located on an opposing side of the lobe rotor, wherein the first lobe rotor and second lobe rotor are synchronised for rotation in the same direction and speed.The mechanism as claimed in claim 7, wherein the second cavity rotor includes passages that allow air to pass between a cavity of the second cavity rotor and a rotor body outer surface of the second cavity rotor.The mechanism as claimed in any one of the preceding claims, further including at least one gate in the housing, the at least one gate synchronised to open and close in order to allow fluid to flow between a cavity of the cavity rotor and a void formed between the lobe rotor and lobe rotor chamber inner surface and chamber ends.The mechanism of any one of the preceding claims, further including passageways through the housing that allow fluid to flow between a said cavity and a void formed between the lobe rotor and lobe rotor chamber inner surface.The mechanism of any one of the preceding claims, wherein the cavity rotor body and lobe rotor body are formed from combined parts that include hubs and movably attached rotor segments that have contacting surfaces configured to contact the corresponding inner chamber wall and adjacent rotor, thereby enabling active sealing of the corresponding chambers.The mechanism as claimed in claim 11, wherein the movably attached rotor segments are balanced to the centrifugal energy of the mechanism thereby minimising friction occurring between contacting component surfaces.The mechanism of any one of the preceding claims, wherein the cavity rotor body and lobe rotor body are formed from parts that include hubs and movably attached rotor segments that have contacting surfaces configured to contact the corresponding inner chamber wall and adjacent rotor, thereby enabling active sealing of the corresponding chambers, and wherein the hinged rotor sections are balanced such that when a RPM threshold is reached the contacting surfaces move closer to their hub axes and temporarily have a fine clearance from the chamber inner wall, in order to reduce frictional energy loss.The mechanism of any one of the preceding claims wherein portions of the said lobe and cavity rotors include replaceable contacting surface portions, such that material that is more suitable for mechanical sealing than what the rotor components are constructed from can be fitted to the rotor tips.The mechanism as claimed in the preceding claim 2, wherein at least one inlet port is located in the overlapping area of the chamber such that compressed fluid can be introduced into the said cavity trailing portion, an area defined by a said forward concave surface of the cavity and a said lobe trailing convex surface and the housing ends, such that the mechanism can operate as a compressed air or other compressed gas powered engine wherein the rotors are forced to turn as the fluid is introduced.The mechanism as claimed in the preceding claims 15, wherein at least one fuel port is located in the overlapping area of the chamber such that high pressure fuel and air can be introduced into the said cavity trailing portion and immediately ignited.The mechanism as claimed in the preceding claim 16, wherein the said inlet and fuel ports are located in the said trailing cavity portion are injection ports that can be activated at a variety of degrees as a lobe passes through a cavity such that the mechanism can operate as an engine that has a variable sized combustion area, and which enables the engine to ignite a smaller than capacity fuel and air load that can then be expanded to have a greater expansion than compression ratio, before being expelled from the engine.An internal combustion engine including a mechanism as claimed in any one of the preceding claims, wherein the rotor body of the lobe rotor includes diametrically opposed recesses situated approximately halfway circumferentially between each said lobe, such that during part of a cycle of the mechanism a lobe rotor recess aligns with an outer surface of the cavity rotor body to create a passage for fluid that is trapped beside one lobe and compressed during part of the cycle to egress via the recess into the adjacent space beside the other lobe.An internal combustion engine including a mechanism as claimed in any one of the preceding claims, wherein the rotor body of the cavity rotor includes three evenly spaced recesses situated approximately halfway circumferentially between each cavity, such that during part of a cycle of the mechanism a cavity rotor recess aligns with an outer surface of the lobe rotor body to create a passage for fluid that is trapped beside one lobe and compressed during part of the cycle to egress via the recess into the adjacent space beside the other lobe.An internal combustion engine, including a mechanism as claimed in any one of the preceding claims, wherein the rotors are formed from hubs with movably attached rotor segments that enable active sealing of the corresponding chambers with contacting surfaces of the rotor segments, and wherein the hinged rotor segments automatically open and close passageways between the cavity and lobe rotors and the housing as the rotor segments sweep the inner surfaces of the chambers such that during part of the engine cycle at least one hinged cavity rotor segment interacts with the said lobe rotor body to open at least one passageway between the cavity rotor and the cavity rotor housing portion to allow fluid to flow between a said cavity and a corresponding space adjacent to the lobe rotor.A fluid pump, including the mechanism of any one of claims 1-20.An engine, including the mechanism of any one of claims 1-20.

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