Rand cam engine
Encyclopedia
The RadMax engine, also known as Ram-cam or Rand-cam engine is a pistonless rotary engine
being developed by Reg/Regi Technologies Inc.
has a cylindrical housing, and the interior surface of either end of the housing forms a sinusoidal cam, such that the displacement along the engine's axis of any point on the interior surface varies sinusoidally as
, each cam having two 'peaks' and two 'valleys'. The two cams at either end are offset by 
with respect to each other, such that the peaks of one end line up with the troughs of the other end and the interior of the engine between the two cams has constant length along the axis of the engine at all points.
Between these two sinusoidal surfaces, a cylindrical rotor occupies almost all the cylindrical space between the two cams, and holds a series of vanes, 12 in current designs, dividing the interior space into 12 segments. The vanes make contact with both cams at either end of the housing, and move freely up and down these sinusoidal tracks through slots in the rotor.
The spaces between the rotor and each cam, and between the vanes, form combustion chambers whose volume varies in an approximately sinusoidal manner as they are swept around the engine, and into the cams at either end are inlaid induction, exhaust and fuel injection ports at appropriate points around the cycle, so each of the 24 rotating combustion chambers goes through a complete 4-stroke combustion cycle as it rotates.
This engine was invented by the Canadian inventor James McCann.
output. Whereas a 4-cycle
piston engine's piston is only powered only once every second turn of the crankshaft, and a Wankel engine is powered once each turn of the e-shaft, a Rand-cam engine is powered 24 times per revolution of its main shaft. It can also achieve high compression ratio
s for diesel
operation.
stage. According to their published information, the prototype will deliver 42 bhp from a unit only 6 inches (152.4 mm) wide by 6 inches (152.4 mm) long with a weight of 40 pounds (18.1 kg). That is a weight/power ratio of about 1:1. It can run on ethanol
, natural gas
, diesel, LPG
(propane) or hydrogen
. There are immediate plans to demonstrate the engine. The first intended users are military contractors.
corporation developed this concept for a hydrostatic piston actuating mechanism for big diesel engines.
Pistonless rotary engine
A pistonless rotary engine is an internal combustion engine that does not use pistons in the way a reciprocating engine does, but instead uses one or more rotors, sometimes called rotary pistons...
being developed by Reg/Regi Technologies Inc.
Design
The engineEngine
An engine or motor is a machine designed to convert energy into useful mechanical motion. Heat engines, including internal combustion engines and external combustion engines burn a fuel to create heat which is then used to create motion...
has a cylindrical housing, and the interior surface of either end of the housing forms a sinusoidal cam, such that the displacement along the engine's axis of any point on the interior surface varies sinusoidally as
, each cam having two 'peaks' and two 'valleys'. The two cams at either end are offset by with respect to each other, such that the peaks of one end line up with the troughs of the other end and the interior of the engine between the two cams has constant length along the axis of the engine at all points.Between these two sinusoidal surfaces, a cylindrical rotor occupies almost all the cylindrical space between the two cams, and holds a series of vanes, 12 in current designs, dividing the interior space into 12 segments. The vanes make contact with both cams at either end of the housing, and move freely up and down these sinusoidal tracks through slots in the rotor.
The spaces between the rotor and each cam, and between the vanes, form combustion chambers whose volume varies in an approximately sinusoidal manner as they are swept around the engine, and into the cams at either end are inlaid induction, exhaust and fuel injection ports at appropriate points around the cycle, so each of the 24 rotating combustion chambers goes through a complete 4-stroke combustion cycle as it rotates.
This engine was invented by the Canadian inventor James McCann.
Advantages
The claimed advantages of the rand-cam engine are its compactness and its powerPower (physics)
In physics, power is the rate at which energy is transferred, used, or transformed. For example, the rate at which a light bulb transforms electrical energy into heat and light is measured in watts—the more wattage, the more power, or equivalently the more electrical energy is used per unit...
output. Whereas a 4-cycle
Four-stroke cycle
A four-stroke engine, also known as four-cycle, is an internal combustion engine in which the piston completes four separate strokes—intake, compression, power, and exhaust—during two separate revolutions of the engine's crankshaft, and one single thermodynamic cycle.There are two...
piston engine's piston is only powered only once every second turn of the crankshaft, and a Wankel engine is powered once each turn of the e-shaft, a Rand-cam engine is powered 24 times per revolution of its main shaft. It can also achieve high compression ratio
Compression ratio
The 'compression ratio' of an internal-combustion engine or external combustion engine is a value that represents the ratio of the volume of its combustion chamber from its largest capacity to its smallest capacity...
s for diesel
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
operation.
Current status
The engine is currently under development by the US based company Regi U.S., Inc and has reportedly reached the prototypePrototype
A prototype is an early sample or model built to test a concept or process or to act as a thing to be replicated or learned from.The word prototype derives from the Greek πρωτότυπον , "primitive form", neutral of πρωτότυπος , "original, primitive", from πρῶτος , "first" and τύπος ,...
stage. According to their published information, the prototype will deliver 42 bhp from a unit only 6 inches (152.4 mm) wide by 6 inches (152.4 mm) long with a weight of 40 pounds (18.1 kg). That is a weight/power ratio of about 1:1. It can run on ethanol
Ethanol
Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...
, natural gas
Natural gas
Natural gas is a naturally occurring gas mixture consisting primarily of methane, typically with 0–20% higher hydrocarbons . It is found associated with other hydrocarbon fuel, in coal beds, as methane clathrates, and is an important fuel source and a major feedstock for fertilizers.Most natural...
, diesel, LPG
Liquified petroleum gas
Liquefied petroleum gas is a flammable mixture of hydrocarbon gases used as a fuel in heating appliances and vehicles. It is increasingly used as an aerosol propellant and a refrigerant, replacing chlorofluorocarbons in an effort to reduce damage to the ozone layer...
(propane) or hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
. There are immediate plans to demonstrate the engine. The first intended users are military contractors.
Rand cam pump
Similar technology has been proposed for pumps and hydraulic motors. The KruppKrupp
The Krupp family , a prominent 400-year-old German dynasty from Essen, have become famous for their steel production and for their manufacture of ammunition and armaments. The family business, known as Friedrich Krupp AG Hoesch-Krupp, was the largest company in Europe at the beginning of the 20th...
corporation developed this concept for a hydrostatic piston actuating mechanism for big diesel engines.