GB2133474A - A rotary internal-combustion engine - Google Patents

Abstract

The engine comprises a multi- lobed rotor (RO) mounted for rotation (R) within a housing (H), working chambers (CH) being formed between the rotor and the housing by vanes (V), which are supported at their mid- portions by guides (VG) allowing the vanes to undergo both sliding and oscillating movements. The radially outer portions of the vanes are connected to rotor-driven crankshafts (CS), which rotate in the opposite direction to the rotor, the speed ratio being equal to the number of rotor lobes (GL) and (PL). The vanes are thus maintained in gas-tight sliding contact with the rotor periphery. Gases are admitted to, and expelled from, the working chambers via ports (IP) (EP) in the rotor and ports in housing side covers, Fig. 3. The rotor may have a generally square configuration, Figs. 6 and 7. <IMAGE>

Description

SPECIFICATION A rotary internal combustion engine This invention relates to rotary internal combustion engines. It is well known that power is wasted in reciprocating piston combustion engines due to the factthatthe pistons are caused to be moved first one way and then the other, and power is obviously consumed in continuously stopping and starting the pistons for each new piston stroke. Known rotary internal combustion engines also waste power in that the rotors ofthese engines tend to oscillate and again power is consumed by this oscillatory motion.It is an aimofthe present invention to provide a rotating variable -volume device which will function in the manner of a rotary internal combustion engine, in which the power developed within the engine is applied to the periphery ofthe rotor and substantially in the direction ofthe rotor, so that the rotor is continuously rotated in one direction withoutthe application of excessive reciprocating forces tending to impede its progress in a substantially circular forward direction.Accordingly, this invention provides a rotary internal combustion engine which will operate on the four cycle principle, comprising a rotor having a plurality of peripheral lobe portions formed at equiangular intervals, mounted for rotation within a housing and side covers, the housing having substan tially circular inner profile.A plurality of discrete variable volume gas compression chambers formed between the rotor housing and side covers, by a plurality of vanes, which are each mounted in the housing for radial and oscillating motion by means of substantially gas -tight oscillating vane guide members. The outer radial portions of the vanes are each attached to eccentrically rotatable crankshafts which are located in an outer radial portion of the housing and are synchronously connected by gearing means to the rotorshaftin a mannerwherebythe crankshafts are caused to rotate in a counterwise or opposite direction to the rotor and ata ratio directly equal to the number of lobes with which the rotor is equipped, thereby an engine having a rotor with two lobes will havecrankshafts which are geared to rotate twice per each revolution of the engine rotor, likewise an engine having four lobes will have crankshafts which are geared to rotate fourtimes per each revolution ofthe engine rotor. The vanes each having attachment to the crankshafts will be caused therebyto rotate with the crankshafts at their outer radial portions also in a counterwise direction to the rotor.The vanes having rotation at their outer radial portions are each disposed radially inward, extending towards the periphery ofthe engine rotor, and are each slideably located in the housing by means ofsubstantially gas tight oscillating vane guide members, the said vane guide members may be of modularof unitconstruction and are located within substantially circular appertures formed in the housing. The described action of vanes rotatable in a counterwise direction to the rotor at their outer radial portions and slideably located within the oscillating vane guide members, having a combined effect whereby in operation of the engine, the inner radial portions ofthe vanes may be maintained in substantial gas -tight slidable contact with the rotor periphery throughout all phases of engine operation.The inner radial portions of the vanes being provided with sealing elements which may be spring biased or pressure assisted, sealing elements are also provided in the rotorfaces and the side covers.

The rotor is formed for rotation within the engine housing, advantageously having an even number of lobe portions, equidistantly spaced at the rotor periphery, the said lobe portions are evenly divided into two types of lobe which are gas lobes and power lobes, to effect the necessary induction, compression, power and exhaust phases ofthe engine cycle. The gas lobes having the same profile as the power lobes, but are provided with conduit appertures or ports adjacentthe apex ofthe lobe, for the admittance and expulsion of gases. The appertures or ports on the leading side ofthe lobe providing the exhaust phases, and ports on the trailing side ofthe lobe providing the induction phases of the engine. The ports will preferably be formed at advantageous locations in the gas lobe periphery whereby in operation of the engine.The inlet port will be caused to pass into a chamber of the engine atthe same time that the exhaust port is caused to pass from the chamber on the opposite side of the gas lobe, performing a similar function to the opening and closing of the inletand exhaust valves or valve timing overlap atT.D.C. in a conventional reciprocating four stroke engine.The rotor which may be of modular or single construction could have substantially circular gallery's formed in the sides of the rotor face for providing constant conduit transfer of gases from the ports in the rotor peripheryto the gas inlet ports and gas outlet ports which may be formed in the engine side covers, an alternative means of admitting gasestoandfromthe engine could be effected via apperture's provided in the rotor shaft-through the axis of the engine.

Whilst an engine of the present invention may be constructed having any practical number of chambers formed between the vanes, which may not necessarily be spaced at equiangular intervals, advantageously the engine housing and side covers could be constructed according to a geometric formula in a manner whereby the crankshaft centres and the vane guide centres would be formed at specific radial locations in the engine housing and side covers in a manner whereby their radial distance from each other, would be substantially equal to the radial distance ofthe vane guide centres from the engine axis -- d ivided by the numberoflobesformed on the rotor periphery, a rotary engine of the present invention when constructed in accordance with th is formula could have vanes which are maintained in constant sliding contact with the rotor periphery and are also maintained at a substantial 90 degree attitude to the tangeant ofthe rotor periphery throughout all phases of engine operation.An embodiment ofthe engine mayhavevane'swhich are not maintained ata substantial 90 degree attitude with the tangeant of the rotorthroughoutthe engine cycle, accordingly there- by, the location of vane guide centres and crankshaft centres, may not necessarily be geometrically related to the engine axis orthe number of rotor lobes, and the rotor profile ofthis embodiment would be formed of a shape solelyforgas -tight sliding contact with the loci of the vane seals.

Whilst a preferred embodiment of the engine would be constructed having a rotor equipped with an even number of rotor lobes, an alternative embodiment may be constructed having a rotor equipped with an odd or uneven number of lobes and could not therefore be evenly divided into power lobes and gas lobes, such an engine may have one or more lobes which are adapted to repeat any of the induction, compression, power and exhaust phases ofthe engine cycle, or may be adapted to perform a function of any adjacent lobe.

In the construction of an engine ofthe present invention, combustion chambers are formed around the periphery ofthe rotor by vanes, these vanes would preferably be arranged in the housing at equal angular intervals, and any practical number of vanes may be employed for the optimum function ofthe engine.It may however be desired to construct an engine having combustion chambers of unequal adjacent proportions, accordingly the vanes could be arranged in the housing at unequal angular intervals, it will be appreciatied that a variable - volume rotatable device of the present invention may be constructed having a rotorwith any number of lobe portions which are adapted to include peripheral porting arrangements adjacentto the apex of the lobe, an embodiment thus constructed could be used substantially solely for the pumping of fluids or gases, furthermore a preferred embodiment of the engine would include sparking plugs orfuel injectors to provide the ignition phases of the engine, or alternatively may be driven by compressed gases which may be supplied from an external source.Cooling and lubrication ofthe engine and engine rotor may be effected by means of conduit appertures formed in the engine components. An embodiment ofthe invention will now be described solely by way of example and with reference to the accompanying drawings in which: Fig 1: is a schematic view of a preferredembodi- ment ofthe rotary engine in accordance with the present invention, and illustrates a two lobed embodimenttaken from the inlet side, through the axis ofthe engine with the side covers removed.

Fig 2: is a schematic view of a suitable gearing arrangement for a two lobed embodiment ofthe engine taken from the exhaust side of the engine on the opposite side to Fig 1: with the gear cover removed.

Fig 3: is a schematic cross section at right angles to Fig 1: viewed from direction D.

Figs4 & 5: are schematic views of a two lobed rotor as in Fig 1: illustrating means of admitting gases to and from the engine.

Fig 6: is a schematic view of a four lobed embodiment ofthe engine through the engine axis with the side covers removed.

Fig 7: is a schematic perspective view of a four lobed rotorasin Fig 6: illustratinginletandexhaustports and inlet gallery.

Referring now to the drawings Figs: 1 to 4 and in particularto Fig 1: there is shown a rotary internal combustion engine which is a two lobed embodiment of the present invention and comprises a rotor (RO) having two lobes (PL) and (GL) formed at opposite sides ofthe rotor periphery (RP) and are spaced at equiangular intervals from the rotor axis (AX).The rotor (RO) is mounted for rotation (R) within a housing (H) and side covers (SC), the housing (H) having a substantially circular inner profile (PR). Variable volume gas- compression chambers 1,2,3,4,5, and 6 areformed between the housing (H),the rotor periphery (RP) and side covers (SC), by six vanes (V), which are radially disposedfromthe rotor periphery (RP) and are each located within substantially circular shaped appertures in the housing (Hl byvane guides (VG), providing the vanes (V) with substantially gas tight, sliding and oscillating motion at their mid portions. The vanes (V) are each attached attheir outer radial portionsto crankshafts (CS).The crankshafts (CS) are each connected to the rotor shaft by gears (RG) (G) and (CG) and are constructed and assembled in a manner whereby the crankshafts (CS) will be caused to rotate in the opposite direction to the rotor (RO) and at a ratio equal to the number of rotor lobes (PL) and (GL), accordingly therefore a two lobed embodiment ofthe engine as in Figs: 1,2 and 3 is provided with gears (RG), (G) and (CG) for effecting the crankshaft rotation (CR) at twice the speed ofthe rotor (RO), ortwo revolutions ofthe crankshafts (CS) per each 360 degrees counterwise revolution of the rotor (RO),thevanes (V), havingattachmenttothe crankshafts (CS) are caused to rotate with crankshafts (CS) attheirouter radial portions, also in a counterwise direction to the rotor (RO), and attheir mid portions are caused to slide in a radial and oscillating mannerwithin the vane guides (VG) which are located within substantially circular shaped appertures formed in the housing (H).The described action of vanes (V) which are caused to rotate in a counterwise direction to the rotor (RO) attheir outer radial portions -whilst sliding and oscillating within the engine housing (H) having a combined effect, whereby the inner radial portions of the vanes (V) are maintained in a substantially gas -tight sliding contact with the rotor periphery (RP) throughout all phases of engine rotation, inner radial portions of the vanes (V) being provided with seal elements (VS) which may be spring biased or pressure assisted. The rotor (RO) ofthe engine in Fig: 1 is constructed having two lobes (PL) and (GL).The gas lobe (GL) is provided with an inlet port (IP) onthetrailing side ofthe lobe (GL)and is connected in a conduit mannerto a substantially circular induction gallery (IG) formed in the rotor side face, the induction gallery (IG) is in constant rotatable communication with a gas inlet port (GI) formed in the side cover (SC) of the engine, thereby providing a constant uninterrupted supply of gas to the chambers (CH), the leading side ofthe gas lobes (GL) is provided with an exhaust port (EP) which is connected in a conduit mannerto a substantially circular exhaust gallery (EG)formed in the rotorsideface on the opposite of the rotor (RO) from the induction gallery (IG). The exhaust gallery (EG) is in constant rotatable communication with a gas outlet port (GO) formed in the side cover (SC) on the opposite side ofthe engine from the gas inlet port(GI), gas seals (GS) and (RS) are provided in the side covers (SC) and the rotor side faces forthe containment of gases, an alternative method of admitting gases to the engine isdiagrama- tically illustrated in Fig: 5 whereby gas is admitted to the engine via a conduit apperture in the rotor shaft (RT) passing through the axis (AX) of rotor to the inlet port (IP). Gases may be expelled from the chambers (CH) by way of the exhaust port (EP) and passed through theapperture formed in the rotor shaft (RT) on the opposite side of the engine.Refering now to Figs: 6and7 and in particularto Fig: 6which is an embodiment of the present invention having eight gas - compression chambers (CH) numbered 1,2,3,4,5,6, 7, and 8 and is equipped with a four lobed rotor (RO) having two gas lobes (GL) formed atopposite sides of the rotor (RO) and spaced at angular intervals of 180 degrees, two power lobes (PL) are provided on opposite sides ofthe rotor (RO) and are equidistantly interspaced from the gas lobes (G L) at angular intervals of90 degrees, the gas lobes (GL) each being provided with an inlet port (IP) and an exhaust port (EP).The operation of this embodiment of the invention (Fig 6) is substantially as described for Figs: 1,2, and 3, and differs mainly in thatthe crankshafts (CS) would be geared to rotate at a ratio of 4to 1 in a counterwise direction to the engine rotor (RO), and the engine components could be constructed according to the geometric diagrams in Figs: 16 and 17, and in operation ofthe engine (Fig 6) would also be igniting simultaneously at opposite sides ofthe rotor.A rotary engine of the present invention may be constructed in a mannerwhereby, in addition to the necessary requirement of having vanes (Vì which are maintained in constant gas - tight sliding contact with the rotor periphery(RP)throughoutAll phases of engine rotation a further requirement ofthe engine construction may be that the vanes (V) are also desired to be constantly maintained at a substantial 90 degree attitude to the rotor periphery(RP) throughoutall phases of engine rotation,this 90 degree attitude can be achieved by the correct radial placement of the vane guide centres (VGC) and the crankshaft centres (CC) in the engine housing (H) and side covers (SC) and is refered to as the 90 degree condition (90C) in Figs 16 and 17.Referring now to Fig: 6, there is shown a quartersection of a two lobed rotor(RO) constructed on a base line (BS) and in Fig: 17there is shown a quarter section of a four lobed rotor (RO) constructed on a base line (BS).In the construction of an engine having any number of rotor lobes, the optimum radial location of the vane guide centres (VGC) may be selected at a distance (A) from the engine axis (AX), this distance (A) when divided by the number of rotor lobes will provide the optimum radial distance (B) between the vane guide centres (VGC) and the crankshaft centres (CC), by way of example:- dimension (B) in Fig: 16 would be obtained by dividing dimension (A) bytwo, and dimension (B) in Fig: 17 would be obtained by dividing dimension (A) by four.

There is diagramatically shown in Figs: 16 and 17 crankshafts (CS) which are spaced at equal angular intervals of 45 degrees and 22.5 degrees on the circumference of the radial crankshaft centre line (CC) these angular intervals of 45 degrees and 22.5degrees are each equal to a 90 degree portion of the engine divided by the total number rotor lobes (PL) and (GL) and are also equal to the angular rotation required of the engine rotor (RO) to effect a 90 degree rotation of the crankshafts (CS) whereby the eccentric crankpin portion (CP) ofthe crankshaft (CS) will be rotated from 0 degrees on the base line (BS) to position (E) atwhich position the vane (V) will be at or near its maximum angle of deviation to the radial line from the engine axis (AX), and the vane (90C) will be maintained substantially at 90 degrees to the tangeant of the rotor periphery (RP).

The profile ofthe rotor periphery (RP) is defined collectively by the radius (RC) ofthe crankpin portion (CP) ofthe crankshaft and the radial locations of the vane guide centres (VGC) relativetothecrankshaft centres (CC), the lobe portion (P) ofthe rotor (RO) which is defined between the base line (BS) and the extended vane line (D) is a radius generated from point (C) which is the point where the extended vane line (D) intersects the base line (BS).

The operation of the engine will now be described with reference to the accompanying drawings and in particularto Figs: 1 and 3, where in is shown a two lobed rotor (RO) mounted for rotation (R) within a stationary housing (H) and a fully expanded chamber (CH) (No: 1) which at this phase of the engine cycle, would be filled with exhaust gases. The engine rotor now rotates in direction (R) and the lobe portion (GL) ofthe rotor (RO) will be passed into the chamber (CH) (No: 1) and as the volume ofthe chamber (CH) decreases, exhaust gases will be forced from the chamber (CH) passing through the exhaust port (EP) in the rotor periphery (RP) to the exhaust gallery (EG) formed in the rotor (RO) side face, the exhaust gases are now passed into the exhaust outlet (EO) formed in the engine side cover (SC).When the apex ofthe gas lobe (GL) is at or nearthe centre of the chamber (CH) then the chamber (CH) will be emptied of gases and the exhaust port (EP) passes from the chamber (CH) at the same timethe induction port (IP) passes into the chamber (CH), thus commencing the induction phase ofthe engine cycle, as the rotor (RO) continues in direction (R) the chamber (CH) expands, and gas is drawn into the chamber (CH) through the induction port (IP) from the gas inlet port (GI) formed in the engine side cover (SC) via the substantially circular induction gallery (IG) formed in the rotor (RO) side face. When the induction port (IP) passes from the chamber (CH), the chamber (CH) will nowbefully expanded and contain a volume of gas. The power lobe (PL) portion of the rotor (RO) now passes into the chamber (CH) thus commencing the compression phase of the engine cycle. The rotor (RO) continuing in direction (R) now compresses the gas, until the apex ofthe power lobe (PL) is at or nearthe centre ofthe cham ber (CH), the chamber (CH) wil I now be at its minimum volume and maximum compression, the gas may now be ignited by a sparking plug (SP) or similar means of ignition, or fuel injection etc.The ignited gas now expands in the chamber (CH) thrusting the trailing side ofthe power lobe (PL) in a forward direction (R) continuing until the chamber (CH) is fully expanded, and the exhaust port(EP) on the leading side of the gas lobe (GL) now passes into the cham ber (CH) and the chamber (CH) will be ready to recommence the engine cycle, whilst the action of one chamber (CH) (No: 1) only has been described, it is to be appreciated that the same sequence of engine phases will occur consecutively on all other engine chambers (CH), this is illustrated in Figs: 8 to 15, and shows a power lobe (PL) of the rotor (RO) at its maximum pointofcompression, igniting on No: 1 chamber (CH) in Fig 8, and expanding whilst the rotor (RO) rotates in a forward direction (R) progressing at intervals of 10 degrees.When the rotor (RO) has rotated through 60 degrees in Fig: 15 the power lobe (PL) is now at its maximum point of compression on No: 2 chamber (CH) and will now be igniting on this chamber(CH) (No:2) although itwill be seen that No: 1 chamber (CH) is notyetfully expanded, furthermore on a four lobed embodiment ofthe engine (Fig 6) the same sequence of events will occur simultaneously on opposite sides ofthe rotor (RO).

Cooling of the engine and engine rotor (RO) may be effected by passing fluid through passages (EC) formed in the engine components, it isto be appreci ated that the embodiments ofthe engine described within, have been given by way of example only and that alternative embodiments may be employed. Thus forexamplethe number and shape ofthe rotor lobes (G L) and (PL), the number of gas - compression chambers (CH), and the shape ofthe substantially circular inner profile (PR) ofthe engine housing (H). A variation in engine capacity per rotor (RO) can be achieved by increasing or decreasing the diameter of the engine rotor (RO) and housing (H) or the width of the rotor (RO) and housing (H), furthermore, alternative embodiments may be constructed having two or more rotors (R) on a common axis (AX) and included within a wider housing (H).

Claims (10)

1. A rotary internal combustion engine comprising: a rotor having a plurality of peripheral lobe portions formed at equiangular intervals; mounted for rotation within a housing and side covers; the said housing having substantially circular inner profile; a plurality of discrete variable - volume gas compression chambers formed at equal or unequal angular intervals and defined between the said rotor the housing and side covers; by a plurality of vanes each disposed radially from the peripheryofthe rotor tangeant at a substantial 90 degree or perpendicular attitude; and located attheir mid portions within substantially circular shaped appertures formed in the housing; each said vane having substantially gas tightvane guide members located between the mid portion ofthe vanes and the substantially circular shaped appertures in the housing; providing radial and oscillating motion of the vanes; the vanes each having means for attachment attheir outer radial portions to eccentrically rotatable crankshafts; each said crankshaft mounted for rotation within the outer radial portion of the housing; the crankshafts each having gearing arrangement co-ordinate with the rotor effecting rotation ofthe outer radial portions of the vanes in a counterwise or opposite direction to the rotor; the said gearing arrangement providing rotation ofthe crankshafts in a counterwise direction to the rotor and synchronised in a mannerwherebythe crankshafts will be caused to rotate at a ratio equal to the number of peripheral lobe portions on the rotor per each 360 degrees counterwise revolution ofthe rotor, thus an engine having two rotor lobes, would have crankshafts which are geared to rotate twice per each counterwise revolution of the rotor, likewise an engine having four rotor lobes would have crankshafts which are geared to rotate fourtimes per each counterwise revolution ofthe rotor; the inner radial portions ofthe said vanes being provided with sealing arrangementforsubstantially constant gas -tight slideable contact with the rotor peripherythroughout all engine operation; whereby in use ofthe engine; compressed gas can be ignited when a power lobe portion of the rotor passes into the chambersformed between the housing the side covers and vanes; to impart powerto the periphery ofthe rotor substantially solely in the direction of rotation ofthe rotor; gases can be admitted to the engine via conduit apperture arrangements in the trailing portion ofthe periphery; gases may be expelled from the engine by conduit apperture arrangements in the leading portion of the rotor lobe periphery.

2. Arotaryinternal combustion engine according to claim 1: having a rotor profile formed for sliding gas tight contact with the inner radial portions of the vanes throughout ail phases of engine rotation.

3. A rotary internal combustion engine according to claim 2: having crankshaft centres and vane guide centres which are located in the engine housing at a radial distance from each other which is substantially equal to the radial distance of the vane guide centres from the engine axis - divided bythe total number of rotor lobes.

4. A rotary internal combustion engine according to claim 3: having radial slideable and oscilating vanes which are caused to remain in a substantial 90 degree or perpendicular gas -tight attitude to thetangeant of the rotor peripherythroughout all phases of engine operation.

5. A rotary internal combustion engine according to claim 2: having a rotor equipped with even number of lobe portions which are evenly divided into two kinds of lobe; one half the number of lobes having appertures adjacentthe apex ofthe lobe to provide induction and exhaust phases ofthe engine cycle; and an equal number of equidistantly interspaced lobes providing the compression and power phases of the engine cycle.

6. A rotary internal combustion engine according to claim 2: having an even or uneven number of rotor lobes whereby one or more lobes ofthe rotor may be used to repeat any cycle ofthe engine: orto perform the same function of any adjacent rotor lobe.

7. A rotary internal combustion engine according to claim 1: whereby an embodiment of the present invention may be constructed to include a rotor having any number of lobe portions which are adapted to include peripheral porting arrangements adjacent to the apex ofthe lobe, an embodiment thus constructed could be used substantially solely for the pumping offluids or gases.

8. A rotary internal combustion engine according to any previous claim having any number of rotor lobes and any number of engine chambers which are defined by vanes which are each attached at their outer radial portions to eccentrically rotatable crank shafts which are each caused to rotate in an opposite or counterwise direction to a rotor having a periphery shape formed for constant sliding contact with the inner radial portions of the vanes.

9. A rotary internal combustion engine substantially as described herein with reference to and as illustrated in the accompanying drawings.

10. A rotary internal combustion engine as claimed in claim 1: substantially as herein before described.