Internal-combustion engines – Free piston – Single chamber; one piston
Reexamination Certificate
2002-04-17
2004-04-20
Yuen, Henry C. (Department: 3747)
Internal-combustion engines
Free piston
Single chamber; one piston
C123S0510AC, C123S053600
Reexamination Certificate
active
06722322
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to internal combustion engines and, more particularly, to internal combustion engines in which a common cylinder and a common piston are shared between a pair of alternate combustion chambers. More specifically, this invention relates to an internal combustion engine of the four-stroke type with a reciprocating piston member which partitions a common cylinder to form two combustion chambers.
BACKGROUND OF THE INVENTION
Internal combustion engines are widely used as power plants for many equipment and apparatuses such as automobiles, power generators, pumps, compressors, ships, tractors, machines, and aeroplanes. In order to supply adequate power, conventional internal combustion engines are generally formed by connecting a plurality of alternately combusting cylinders together. Bach cylinder of an internal combustion engine generally includes a hollow combustion chamber inside which there is disposed a linearly and reciprocally moveable piston member.
In general, the piston is driven towards the cylinder head, which is usually the ceiling of a cylinder, to compress the gaseous fuel mixture introduced into the cylinder during one part of the engine cycle. The subsequent timely combustion of the compressed fuel causes an explosion to drive the piston away from the cylinder head. This movement also drives the connecting power transmission mechanism to deliver the resulting mechanical power outside of the cylinder for the intended use.
In general, 1) fuel intake, 2) compression, 3) combustion and 4) exhaustion are the typical steps involved in a complete engine operation cycle of a conventional four-stroke internal combustion engine. Because an engine cylinder must withstand the enormous explosive force during the engine operating cycles, internal combustion engines are typically made of steel, wrought iron or other ferrous or non-ferrous metal alloys which are inherently heavy and bulky. Since a plurality of engine cylinders are usually connected together to provide sufficient power output as well as for smooth engine operation, the weight of engines becomes an important factor to negotiate if to improve the efficiency of an engine is to be improved. In general, engine designers endeavour to minimize the engine weight-to-power output ratio, or, alternatively, to maximise the power-to-weight ratio per combustion cylinder. Also, in a multi-cylinder engine, usually only one cylinder delivers power at a time which means that the instantaneous power generating engine must also drive the remaining non-power generating pistons and the connecting mechanism. Therefore, it will be beneficial if the connecting mechanism or parts between cylinders can be minimized for a given set of cylinders.
For example, U.S. Pat. No. 6,318,309 describes an internal combustion engine in which two pistons are reciprocatively disposed in each cylinder thereby forming combustion chambers at each end of the cylinder plus a third combustion chamber between the pistons. However, two sets of rather complicated piston connecting rods are required and a third piston is responsible for a specific combustion chamber area not served by the other pistons. U.S. Pat. No. 3,010,440 teaches another example of an internal combustion engine having more than one piston disposed in a single cylinder in which each piston covers its own combustion chamber which is not served by the other piston.
In a conventional four-stroke cycle internal combustion engine, the complete engine operating cycle of fuel intake, compression, combustion and exhaust requires two cycles of linearly reciprocal motion of the piston member. In other words, the piston member has to move up and down twice in order to complete a single engine cycle. Since the engine cycle involving fuel combustion is the only power generating cycle, the other piston cycle is non-power generating but power consuming, noting that the piston is usually always connected to an external load. Hence, it will be highly beneficial if there can be provided an improved internal combustion engine or engine topology which can overcome or at least mitigate the short-comings associated with the afore-said disadvantages of conventional internal combustion engine.
OBJECT OF THE INVENTION
Hence, it is an object of the present invention to provide an improved internal combustion engine or engine topology which overcome or, at least, mitigate disadvantages associated with conventional internal combustion engines. More specifically, it is an object of the present invention to provide an improved internal combustion engine or engine topology which serves to improve engine performance by reducing the engine weight-to-power output ratio. It is also an object of the present invention to provide an internal combustion engine or engine topology in which the piston only needs to go through a single set of leniently reciprocal motion in order to complete the fuel intake, compression, explosion and exhaust cycles of an engine operation. As a minimum, it is at least an object of the present invention to provide the public with a choice of a novel internal combustion engine or engine topology to be described hereinafter.
SUMMARY OF THE INVENTION
In view of the afore-said objectives and according to the present invention, there is provided an internal combustion engine including at least one engine cylinder, said cylinder includes a cylinder cavity with first and second cylinder heads which are interconnected by a cylinder wall, said cylinder includes a piston member which is slidably movement within said cavity and between a first and a second extreme position intermediate between said first and second cylinder heads, said piston member partitions said cavity into a first and a second combustion chambers which are in alternate combustion when in normal engine operation.
Preferably, said engine further including a slidable diaphram member in each said combustion chamber, said diaphram member includes a spacer separating a cylinder head and the corresponding piston surface of a combustion chamber, whereby defining the minimum volume of said combustion chamber.
Preferably, said engine further including a slidable member disposed in each said combustion chambers and partitioning said combustion chamber in to a first compartment with one end being a cylinder head and a second compartment with one end being said piston, said first and second compartments are generally not mutually communicable except at a specific position of said diaphram member at which position combustible gas in said first compartment will be transferred to said second compartment during normal engine operations.
Preferably, during normal engine operations, combustion occurs in said second compartment of one combustion chamber, that is, in the enclosed space between said diaphram and said piston, such that, during combustion, said piston are driven away from said diaphram and pushed towards the other chamber to compress said other chamber.
Preferably, said engine further including means to drive said diaphram towards said piston to remove exhaust from said cylinder subsequent to each combustion involving the chamber comprising said diaphram.
Preferably, combustible gaseous fuel is introduced into said first compartment of said combustion chamber at the time when exhaust is being removed from said second compartment of said chamber.
Preferably, combustible fuel is introduced into said first compartment through a valve aperture, said aperture when aligned with a specific part on said diaphram forms a communication path between said first and second compartments, thereby allowing compressed gaseous fuel to be transferred from said first compartment into the adjacent second compartment.
Preferably, combustion in one combustion chamber forces said piston and the diaphram member of another chamber to move towards the cylinder head of that another chamber to compress the gaseous fuel in said first compartment of that other chamber during normal engine operation.
Preferably, said cylinder is characteri
Benton Jason
Burns Doane Swecker & Mathis L.L.P.
Yuen Henry C.
LandOfFree
Internal combustion engine does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Internal combustion engine, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal combustion engine will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3244098