Brian Collins -- Collins Cycle Engine ![](0logo.gif) [rexresearch.com](../index.htm) --- Brian COLLINS Collins Cycle Engine --- **Popular Science - Vol. 236, No. 1 - Jan 1990 - Page 56** **books.google.com/books?id=8odMlvCz19IC** Designed by inventor Brian Collins in Perth, Australia, the power plant departs significantly from conventional engines, two-stroke or otherwise... ![](p2a.jpg) ![](p1.jpg) ![](p2.jpg) ![](p3.jpg) --- Excerpts from Collins Motor Corporation Ltd Literature, ca. 1980 History of the Collins Engine Several years ago Mr Brian Collins began a project to design an efficient multi-fueled engine. During the course of development a unique air/fuel induction system was designed, and is now known as the 'Collins Cycle'. This cycle is the principle which enables the Collins Engine to utilize efficiently many different fuels. The first engine to incorporate Collins Cycle was a 700 cc four chambered Mark 1 model. The Collins Cycle radically altered the traditional engine design by eliminating valves and associated parts; in fact, the engine has only five moving parts. The operating performance of the MK1 has been remarkable. A prototype engine, lacking sophistication and requiring optimizing to realize its full potential, will start instantaneously on a variety of fuels, idle and accelerate effortlessly from 250 rpm - 3000 rpm, and has run for many accumulated hours without the slightest problem. An emission test conducted while the MK1 engine was running LPG produced a carbon monoxide emission level too minute be recorded on the test equipment. A miniature 16 cc version was built to investigate the feasibility of adapting the Collins Engine concept into a very small mechanical unit, particularly suited to a handheld power source application. A third engine, a 2 liter MK II similar to the MK I but fitted with an integrated lubrication and cooling as installed in a vehicle in April 1979. Operating Principle The Collins engine is a four-firing system, utilizing a breakthrough in efficient combustion technology known as the Collins Cycle, whereby four chambers produce the equivalent work output as that of a conventional 8-cylinder engine. Engine Components The engine consists of a circular aluminum alloy block, four junk heads, four firing chambers and an orbiting yoke mounted on a single-throw crankshaft. Engine Description The junk heads are inserted from the outside, into the open ends the cylindrical firing chambers. These low mass firing chambers reciprocate in cast iron-lined bores, machined rain the engine block, in one plane, at 90 degrees to each other. The motion of the chambers is controlled by a unique sliding connection to a square orbiting yoke which is journaled to the crankshaft. It should be noted that, when the junk head is positioned in the firing chamber, and located on the block, the important pumping chamber is formed. Lubrication The MK II engine is lubricated oil, pumped from a reservoir, through ducted oil ways in the crankshaft Balancing It is a straightforward operation to balance the engine internally, and a turbine-like smoothness. Cooling The MK II version has a standard integrated liquid cooling system consisting of a water pump, radiator and thermostatically controlled fan. Due to the engine's particular design, adiabatic cooling effect takes place when a charge of air is drawn into the pumping chamber at each cycle, and forced through the air transfer ports into the firing chamber. This adiabatically co led air swirls around in the inner walls of the chamber, assisting to absorb the residual heat after each firing cycle. How the Engine Operates A clean charge of air is pumped into the hemispherical firing chamber every cycle, forcing the expended charge out of the ported system. The fuel is injected into the incoming turbulent air stream producing an excellent air/fuel mix. The air/fuel mixture is fired by centrally located spark plug, producing an ideal flame propagation, which results in a clean burn. Fuels A particular feature of the engine is its ability run on a variety of fuels, including natural gas, liquid petroleum gas, hydrogen, petrol, diesel, grain alcohol, and methane. Ignition Ignition is by a standard coil and electronic distributor the spark plugs, situated in the center of the junk heads. The junk heads can be adjusted to vary the compression ratio from 6:1, to 18:1. The spark plugs may be replaced with diesel injectors for compression ignition. Other Design Features & Advantages Perhaps the Collins Engine's most important feature is its simplicity. The engine consists of five major moving parts and a crankshaft, utilizing largely conventional automotive type components, for example, standard rings and bearings. In addition, all wearing surfaces employ known technology. The design eliminates the problems of a valve train with its associated machining costs, engine timing problems and noise factors. The engine can be manufactured on conventional machine tools requiring minimum supervision and in approximately half the time required to manufacture a conventional 8-cylinder engine. During the course of the engine's operation, it produces large volumes of compressed air that may be used for brakes, air motors, and other pneumatic control systems. --- Excerpt: A Preliminary Appraisal of the Collins Engine, Mark I Model Brief Description of the Engine The Collins Engine MK I, 700 cc capacity, operates basically on the pressure scavenged 2-stroke principle. Four cylinders or combustion chambers are mounted radially around the engine body; the pistons are static, being integral with the head reciprocating member comprising the firing chamber and shoe; power is transmitted to a single throw crankshaft through an orbiting yoke; each power chamber is self-contained. Normal aspiration induces a charge of air through a reed valve, into a mixing void around a cylinder ( volume being 50% in excess of the swept volume ); on closing of the reed valve, pressure develops prior to uncovering of the charging port, pressure charging and scavenging the firing chamber. Conventional piston rings are employed throughout where pressure sealing is required. --- **US4331108** **Radial engine** Inventor: COLLINS BRIAN S EC: F01B1/06B // F01B1/06K4 // F01B13/06B IPC: F01B1/06 // F01B13/06 // F01B15/02 This invention relates to a rotary engine. In particular the invention relates to an engine of the form disclosed in Australian Document No. 466936. In one form the invention resides in a displacement engine comprising a substantially cylindrical housing, a rotor rotatably mounted in said housing on an axis parallel with the longitudinal central axis of the housing, a plurality of tubular elements each slidably mounted over fixed piston elements projecting substantially radially inwardly from the housing, said tubular elements being closed at their inner ends and held at their inner end in slidable and/or rolling engagement with the circumferential outer surface of the rotor, said rotor being such as to cause reciprocation of the tubular elements over the piston elements upon the rotation of the rotor, such that the volume of the space defined by the interior of the tubular member and the piston element varies with the rotation of the rotor; the wall of the housing surrounding each side of each piston element being such as to define a slot such that the side walls of the tubular element are sealingly and slidably engaged in the slot, wherein a pumping space formed between the walls of the tubular element and the sides of the slot being of variable volume with the reciprocation of the tubular element and being provided with a fluid inlet port in the housing and a port through the cylinder at least one of which, with the reciprocation of the tubular element, opens into the space defined between the interior of the tubular member and the piston to pump fluid into that space. The invention will be more fully understood in the light of the following description of one specific embodiment. The description is made with reference to the accompanying drawings of which: **FIG. 1 is a sectional elevation of an engine according to the embodiment along line 1--1 of FIG. 2; and;** **![](us1.jpg)****FIG. 2 is a sectional elevation along 2--2 of FIG. 1**. ![](us2.jpg) The embodiment shown in the drawings comprises a housing 11 having a number of circumferentially inwardly radially directed piston elements 13 mounted to its inner surface. Each piston element 13 has a cylinder 15 mounted thereon for sliding radial reciprocating movement on the piston element. The formation of the piston elements 13 in the housing 11 is such that the walls of the housing extend radially inwardly around the periphery of the piston element to define a slot 17 having the form of an annular cavity around the piston elements 13 and having the same transverse configuration as the piston element 13. The inner walls of the cylinder 15 are sealingly engaged on their inner curved surfaces by the piston element 13. The open end of the cylinders 15 are provided with outwardly extending flanges 21 which sealingly and slidably engage the outer wall of the slots 17. The piston element 13 is formed such that it is separable from the casing and is provided with an axial passage for accommodating a spark plug 41 at its inner end. The electrodes of the spark plug have direct communication with the combustion chamber formed between the interior of the cylinder 15 and the piston 13. The axial passageway opens to the exterior of the piston to permit access to the spark plug for servicing. The inner end of the cylinder 15 is slidably mounted to the periphery of a rotor 43 which is substantially square in shape and is rotatably mounted on an eccentric crankshaft 45 which is rotatably mounted in the casing on an axis substantially in alignment with the casings central longitudinal axis whereby with rotation of the crankshaft the rotor executes an orbital motion within the casings. As mentioned the cylinders 15 are formed at their open ends with an outwardly directed annular flange 21, the outer edge of which sealingly engages the outer wall of the slot 17. At the upper end of the slot 17 the outer wall thereof at the region adjacent the top of the piston and above, has a reduced diameter portion 47 such that the outer walls of the cylinder 15 are sealingly engaged thereby. As a result the intermediate spaced A formed between the flange 21, the outer wall of the cylinder 15 and the reduced diameter portion 47 of the outer wall of the slot 17 is of variable volume as the cylinder 15 reciprocates in the slot 17. This intermediate space A is in communication with an air supply through a one way valve 30 and intake port 29 (see FIG. 2) and periodically with the interior of the combustion chamber B through a feed port 35 formed through the wall of the cylinder 15 (see FIG. 1). Such periodic communication occurs when the cylinder has approached almost the end of its upstroke, the intermediate space A is at its minimal volume and the combustion chamber B is at its maximum volume. The combustion chamber B exhausts the spent gases through a port 37 provided in the wall of the cylinder 15 and which also opens to an exhaust port 31 formed in the housing 11 when the cylinder 15 is approaching the end of its upstroke (see FIG. 2). A further port 53 is provided in the wall of the cylinder 15 which opens to a mating port 51 in the housing 11 when the cylinder is at the end of its upstroke. Lubrication for the movement of cylinders 15 in the slots 17 and the sliding of the inner ends of the cylinders 15 on the rotor 43 is effected by a periodic supply of lubricant from an oil sump 19. Lubricant for the engine is pumped from the oil sump 19, mounted to the underside of the casing, to an axial passage 23 formed in the crankshaft 45. The axial passage 23 opens into a radial passage 25 in the crankshaft which with rotation of the crankshaft 45 periodically communicates with four equally rotationally spaced radial passage ways 26 formed in the rotor 43 which in turn open onto one of the faces of the rotor 43. The opening of each radial passage 26 in the rotor is located such that with reciprocation of the cylinder 15 on the rotor the radial passage 25 periodically communicates with a further passage 27 formed in the cylinder which opens into the space between the adjacent surfaces of the cylinder 15 and the slot 17. A drainage passage 28 permits the drainage of lubricant into the rotor space and sump 19. The openings of the passageway 27 onto the opposed surfaces of the cylinder 15 and slot 17 comprise a series of openings spaced around both faces of the cylinder 15 and opening into a slot formed in both faces. The slot in both faces supports an oil ring (not shown) which controls the flow of lubricant such that only a thin film of lubricant is introduced onto the opposed faces of the cylinder 15 and slot 17. By means of this arrangement a supply of lubricant is delivered onto the opposed faces of the cylinder 15 and the slot 17 and between the opposed faces of the inner end of the cylinder 15 and the rotor 43. The action of the motor will be described from a point where the volume of the combustion chamber B is at a minimum volume (i.e. ignition). During the expansion of the combustion chamber the space A defined between the walls and the flange 21 of the cylinder and the exterior wall of the slot 17 is reduced and the air which was introduced through the port 29 in the casing and one way valve 30 is compressed until, when the cylinder is at the lower reaches of its stroke the air is permitted to flow into the combustion chamber B from the space A just after the exhaust gases have been vented away through ports 37 and 31 in the cylinder and casing respectively. The entry of the air from the space A into the combustion chamber B serves to scavange the remaining exhaust gases from the combustion chamber while the cooling caused by the expansion of the air in the combustion chamber serves in cooling the combustion chamber. At the bottom of its downward stroke a quantity of fuel is injected into the combustion chamber B through ports 51 and 53 in the casing and cylinder respectively whereupon the cylinder begins its upward stroke to ignition and more air is drawn into the intake space A. However while the invention has been described in terms of a two stroke cycle the engine is equally applicable to a four stroke cycle. In order to reduce the problems of wear the interior cylindrical face of the cylinder may be provided with a wear resistant liner while the exterior face of the slot 17 which is in sliding engagement with the external face of the cylinder may also be provided with a wear resistant liner. The provision of such a liner facilitates the manufacture of the components by casting without the need for machining or hardening of faces of the components. The piston 13 is removable via a head structure 59 which is separable from the casing 11. The head structure has formed within it, a cavity 61 for the flow of coolant through the head structure 59. The space C defined in the slot 17 by the edge of the piston 13 is of variable volume with the reciprocation of the cylinder 15 over the piston 13. This space C may be used as a pumping space for pumping lubricant between the corresponding spaces of each cylinder. Alternatively this space C may be used as an air compressor to provide a forced air supply to the inlet port 29 for the air intake space A. It should be appreciated that the scope of the invention need not be limited to the particular scope of the embodiment described herein. In addition the invention is applicable to any engine incorporating a reciprocating cylinder and static piston and need not be restricted to those of the form disclosed in Australian Pat. No. 466936. --- **AU3053277****ENGINE WITH RECIPROCATING CYLINDERS AND STATIONARY PISTONS** Inventor: COLLINS BRIAN STANLEY Also published as: FR2371577 (A1) JP53081805 (A) DE2751675 (A1) DE2751675 (C2) The present invention relates to an engine similar to the engine described and shown in the statement of Australian Patent No. 466,936. The engine of the invention comprises a casing substantially cylindrical rotor mounted in the housing and rotating about an axis parallel to that of the housing, a plurality of tubular elements which interact with mobile or fixed-organs s' extending radially inwardly of the housing and acting as a piston the tubular elements being closed at one of their ends and bonded to the same ends, the rotor so that each tubular element can slide relative to a fixed member so the volume delimited by the inside of a tubular element and the corresponding fixed member varies with the rotation of the rotor, stationary members each having an annular groove in which slides the blind open end of the tubular element corresponding forming two other variable volumes including a pump, the passages and conduits of the intake and exhaust is also suitable provided in the housing, the tubular elements and the fixed components. In the accompanying drawings, given by way of example **Figure 1 is a sectional elevation of a motor according to the invention along line 1-1 of FIG 2;** **![](fr1.jpg)****Figure 2 is a sectional view along line 2-2 of Figure 1.** ![](fr2.jpg) The engine shown in the drawing comprises a circular housing 11 provided at its periphery and extending radially inwardly of the casing, a number of bodies 13, in this case four, based acting pistons. Each member 13 cooperates with a tubular member 15 corresponding to a movable cylinder slidable relative to alternative member 13. Each member 13 comprises a first tubular portion 13a central (eg cylinder) having one end 13b (toward the center) and a closed end provided with a flange 13c on the basis of an end of a second tubular portion 13d in two parts 17 and 47, part 47 having a shoulder. inside. Each tubular member 15 (acting as a cylinder) comprises a tube closed at one 15a of its ends, 15b, the other end being provided with a collar 21. The inner surface of the tube 15a slides sealing in the first tubular portion 13a of central member 13 so that the side face of the flange 21 slides simultaneously, also tightly, in the second tubular portion 13d of the member 13. With this arrangement is delimited between a body 13 and a tubular element 15, three different volumes variables - An annular space between a face C of the collar 21, the first and second tubular portions 13a and 13d, and the flange 13c; - A volume B between the closed end 13b of the central tubular part 13a and the inner surface of the tube 15a, and - An intermediate space A between the other side of the collar 21, the second tubular portion 13d and the outer surface of the tube 15a. A spark plug 41 is mounted on the wall 13b closing the extreme interior of the first tubular portion 13a, the electrodes of spark plug lead in zone B. Thanks to the tubular configuration of the member 13 the plug 41 is accessible from outside the housing 11. The closed portion 15b of each tube 15 is connected at 22 to a rotor 43 (square outer shape if it has four tubular elements) rotating on a pin 45 of a crankshaft 46, crank pin whose axis is parallel to that of the housing. The tubular elements 15 are therefore entrafnes and animated by a reciprocating: Volumes A, B and C therefore vary dependent manner. The link 22 is provided by a pad 23 secured to the tube 15 and slide in a groove 24 formed in the rotor 43. Alternatively, the shoe 23 can be replaced by a roller. The intermediate space A communicates, via an intake pipe 29 provided with a valve 30 with a source delivering air and depending on the position of a tubular element 15, with the volume chamber B through a passage 35 formed in the side wall of tube 15a. The introduction of air occurs when the element 15 is approaching the end of its stroke (bottom dead center, that is to say, the farthest from the center), volume B is then almost maximum and A volume almost minimal. The combustion gases escape through a passage 37 formed in the side wall of the tube 15a and a pipe 31 passing through the part 47 and the housing 11. The portion 37 and the pipe 31 are connected when the tubular member 15 is adjacent the bottom dead center. Another passage 51 is formed in the wall of the tube 15a and communicates, also in the vicinity of bottom dead center, with a channel 53 work side part 47 and the housing 11. By the passage 51 and the pipe 53, a quantity of fuel is then injected. Then air is introduced into the chamber A. The explosion occurred when the volume is minimal B (top dead center). When A decreases the volume relaxation and air in this volume (Introduced by line 29) is compressed to near the bottom dead center where it is blown into the combustion chamber (maximum volume B) just after the exhaust gas passage 37 and the pipe 31. The supply air sweeps the residual exhaust gas. The foregoing description is made on a combustion engine in two stages. The invention can also be applied to an internal combustion engine with four-stroke or other types of motor, for example a compressed air motor. To minimize the problem of friction portions of the tubular member 15 in contact with the wear of the member 13 corresponding provision was made liners 55 and 57. It possible to envisage a molding manufacturing and possibly avoid machining and thermal treatment that would otherwise be necessary. The volume C can be used to pump lubricant-parties acting on contact element 15 and member 13. In other cases, the volume C can be used to compress the air we then have a compressor that injects air (line 29) in the volume A. The invention can be applied to any machine comprising a piston cooperating with a cylinder and is not limited to the type of engine described in Australian Patent No. 466,936. --- **AU6476074 // AU466936** **ROTARY ENGINE** Inventor: COLLINS BRIAN STANLEY EC: F01B13/04T // F01B15/02 IPC: F01B13/04 // F01B15/02 THIS INVENTION relates to a rotary internal combustion engine. In one form the invention resides in an internal combustion engine comprising a substantially cylindrical housing, a rotor rotatably mounted in said housing on an axis parallel to the longitudinal central axis of the housing; a plurality of tubular elements each slidably mounted over fixed piston elements projecting substantially radially inwardly from the housing, said tubular elements being closed at their inner ends and held at their inner end in slidable and/or rolling engagement with the circumferential outer surface of the rotor, said rotor being such as to cause reciprocation of the tubular elements over the piston elements, upon rotation of the rotor such that the volume of the spaces defined by the interiors of the tubular elements and the piston elements varies with the rotation of the rotor; each space having ignition means and fuel inlet and exhaust outlet means~provided therewith. Unless otherwise specified the term "rotor" should be taken to include an eccentrically mounted rotor having either rotary, or orbital movement or an oval rotor rotating about a cnetral axis, or the like. The movement of the rotor within the casing may be one in which the rotor rotates about a central or eccentric axis or one in which the rotor orbits an eccentric axis. In a preferred form the U shaped chambers are attached to the rotor by means of bearings, preferably the bearings are fitted to the end of the chamber and are mounted in a channel or groove formed in the rotor. The invention will be more fully understood in the light of the following description of two specific embodiments of the invention. The following description is made with reference to the accompanying drawings. **Figure 1 is a sectional view of an engine according to the invention having a rotating rotor.** **![](au46a.jpg)****Figure 2 is a sectional view of an engine according to the invention having an orbital rotor.** ![](au46b.jpg) The embodiment of figure 1 comprises a cylindrical casing 10 having a series of annular slots 12 in its inner peripheral surface. There is mounted in each slot 12 for radial sliding motion therein a cylindrical chamber 14 closed at its innermost end. The portions 16 formed by the slots 12 acting as stationary pistons within the chamber and being provided with sealing means between the walls of the chamber 14 and the portion 16 in the form of sealing rings 18. The portion 16 may be formed integrally in the casing or may be part of a "head" structure 21 as shown which is removable from the casing. In either case the portion 16 at its innermost end carries inlet and exhaust valves and a sparking plug. Rotor 23 is substantially oval in shape and is mounted for rotation on central drive shaft 25. Each chamber 14 is provided with an extension piece 27 having a bearing member 29 which is engaged by a milled annular slot 30 in one end of the rotor. The extension 2'7 is further provided with a gear wheel 32 which engages ring gear 34 to assist in guiding the movement of the rotor in relation to the chamber and absorb some of the load between the two components. The chambers are preferably off set from the radial orientation as shown in order to cause the transfer of motion to be more efficient. Operation of the valves is via pull rods of the type shown as 36, the pull rods for the inlet and exhaust valves are operated by two suitably shaped cams mounted on the drive shaft. To illustrate the operation of the engine chamber A shall be taken as being in the state of ignition and the rotor shall be rotating in a clockwise direction. As a result of ignition an inwardly applied force is applied to the chamber which is transmitted through the gear 32. Chamber F is undergoing the power stroke while chamber E is undergoing the exhaust stroke, the end of which stroke is represented by D. Chamber C has completed the intake stroke while chamber B is undergoing the compression stroke prior to ignition. According to this embodiment for each revolution of the drive shaft each chamber fires once. The embodiment of figure 2 comprises a casing 110 having annular slots 112 equally spaced on its inner surface and having chambers 114 mounted in the slots for radial sliding motion therein. As before the stationary piston 116 may be formed integrally in the casing or formed as shown, integrally in the head 121. A rotor 123 is counted on shaft 125 such that it executes an orbital notion, within the casing. The rotor is polygonal in shape and is provided with milled slots 130 in one end in wrich bearing members 129 of each chamber are engaged. The bearing members being mounted upon extension pieces 127 of each chamber. As in the previous embodiment inlet and exhaust valves are provided at the inner end of pistons 116 and are operated by pushrods in rubbing contact with cams driven from the drive shaft 125. In operation each chamber requires two cycles of the a rotor for each ignition. For illustration chamber shall be taken as undergoing ignition and the movement of the rotor is clockwise. After ignition an inwardly directed force by the chamber is transmitted to the rotor 123 over the contact surface. One complete cycle of the rotor involves the power and exhaust stroke while a further complete cycle involves the intake and compression strokes. A two cycle system can also be used in both embodiments. While the invention has been described with reference to cylindrical chambers sliding in annular slots it need not be so limited. Each chamber may take the form of an elongated channel member mounted in adjacent longitudinal slots with suitable sealing being provided between the ends of the channels and end plates or the ends of the channels may be closed off. Similarly the chambers may have any suitable shaped cross-sectional configuration. While the invention has been described in terms of an oval centrally rotating rotor and an orbiting polygonal rotor the invention need not be so limited. It is within the scope of the invention to include any other form of circulating rotor. The invention while being described in terms of an internal combustion engine having intake valves, exhaust valves, and sparking plugs may also be applied to diesel engines, petrol injected engines, steam engines, compressors, hydraulic motors, hydraulic pump and electric motors and the like. ---