WO2007075047A1

WO2007075047A1 - Rotary engine having piston

Info

Publication number: WO2007075047A1
Application number: PCT/KR2006/005770
Authority: WO
Inventors: Sung-Duck Kim; Radislav Shin
Original assignee: Sung-Duck Kim; Radislav Shin
Priority date: 2005-12-27
Filing date: 2006-12-27
Publication date: 2007-07-05
Also published as: KR100680558B1

Abstract

Provided is a rotary engine having pistons. The rotary engine having pistons includes: a stator in which an air inhalation hole and a combustion gas exhaust hole are formed; a rotor installed at the stator to freely rotate; at least one cylinder formed in the rotor and corresponding to an air inhalation hole and a combustion gas exhaust hole; at least one piston installed inside the cylinder; a fuel supply device; an ignition device; a power conversion device; and a piston ascending and descending induction device. Mechanical efficiency, driving property and durability are greatly improved, shock, friction, noise, and vibration are reduced.

Description

ROTARY ENGINE HAVING PISTON

TECHNICAL FIELD

The present invention relates to a rotary engine, and more particularly, to a rotary engine having pistons, in which a plurality of ascending and descending pistons are installed inside a rotator, the rotator is rotated using an explosive force of a fuel and simultaneously forcible ascending and descending motions of the pistons are induced and forcible exhaust of a fuel gas and forcible inhalation of air by the pistons are possible, so that all of the disadvantages of a conventional internal combustion engine and a conventional rotary engine are overcome and only the advantages of the conventional internal combustion engine and the conventional rotary engine are utilized. Thus, the efficiency and performance of the rotary engine can be greatly increased.

BACKGROUND ART

Conventionally, internal combustion engines, which are widely used in a variety of vehicles, vessels, air planes, tractors, and engine cars, are configured such that a plurality of pistons that linearly move are installed inside a cylinder of an internal combustion engine, the pistons descend due to an explosive force of a fuel, a crank rod connected to the pistons is connected to a crank shaft and thus, linearly descending motions of the pistons are changed into a rotative motion of the crank shaft in order to obtain a rotative power. In addition, a combustion gas, which is generated in the pistons, allows the crank shaft, which rotates using the descending motions of the other adjacent pistons that are exploded subsequently, to forcibly ascend the pistons using the crank rod, and in this case, an exhaustion valve that is disposed above a cylinder is opened to forcibly exhaust the combustion gas. In addition, the inhalation of air that is inhaled into the pistons allows the crank shaft, which rotates using the descending motions of the other adjacent pistons that are exploded subsequently, to forcibly descend the pistons using the crank rod, and in this case, an inhalation valve that is disposed above the cylinder is opened to forcibly inhale air that is inhaled into the pistons. However, in conventional internal combustion engines, shock and friction from the pistons are uniformly applied to the crank shaft during the mechanical conversion of a linear motion into a rotative motion of the crank shaft and the crank rod. Thus, the conventional internal combustion engines have problems in that severe noise and vibration occur, mechanical durability is lowered, efficiency is greatly reduced and material that is weak to shock, such as ceramics, cannot be used.

There are also problems in that the pistons and the crank shaft are disposed in a line, and also, due to unnecessary components such as the inhalation valve and the exhaustion valve, the size of the rotary engine increases. The structure of the conventional internal combustion engine is very complicated due to an increase in the number of components, and thus, the repair or maintenance thereof is complicated and the size of the conventional internal combustion engine cannot be reduced.

To solve these problems, a rotary engine has been developed, wherein the rotary engine has a simple structure in which a plurality of explosive spaces are disposed inside a rotor at equal angles, an air inhalation hole and a gas exhaust hole are installed outside the rotor, fuel is supplied to the explosive spaces and the fuel is exploded. When the explosive spaces are rotated by a rotative force of the rotor and communicate the gas exhaust hole, a combustion gas is naturally exhausted and when the explosive spaces communicate the air inhalation hole, the air is naturally inhaled by the pistons. However, the disadvantages of conventional internal combustion engines are not solved by the rotary engine, and there are serious problems of the rotary engine in that an internal combustion gas is not completely exhausted and the air is not completely inhaled so that a driving property and efficiency of the rotary engine are very lowered, a complete combustion is not performed such that the rotary engine is not environmentally friendly and during a low-speed rotation, inhalation and exhaust are insufficient and during a high-speed rotation, over-inhalation and over-exhaustion occur. In addition, in conventional rotary engines, effective and long-term sealing between a rotor and each cylinder is not easily performed and thus, it is also difficult to mechanically implement conventional rotary engines. DETAILED DESCRIPTION OF THE INVENTION

TECHNICAL PROBLEM

The present invention provides a rotary engine having pistons in which a linear motion of a piston can be smoothly converted into a rotation motion of a rotation portion using the piston that ascends and descends inside of a cylinder that is inclined with respect to the rotation portion along a long groove and using an interlocking shaft rod that is guided by an elliptical track so that a mechanical efficiency, a driving property and a durability of the rotary engine are greatly improved, shock, friction, noise, and vibration of the rotary engine are reduced and the rotary engine can be manufactured using various materials, such as ceramics.

The present invention also provides a rotary engine having pistons in which a plurality of pistons is disposed in one rotation portion at equal angles, the structure of the rotary engine is comparatively simple such that the number of components in the rotary engine is reduced, a repair or a maintenance of the rotary engine is easy, and an ultra-miniaturization and a high output of the rotary engine can be implemented.

The present invention also provides a rotary engine having pistons in which an internal combustion gas is forcibly and completely exhaust, air is forcibly and completely inhaled so that a full combustion is possible, the rotary engine is environmentally friendly, the inhalation of sufficient air and sufficient combustion gas during a low-speed or high-speed rotation is performed, an operating performance of the rotary engine is excellent, a rigid sealing between the rotation portion and each cylinder is possible so that an excellent mechanical performance can be obtained.

TECHNICAL SOLUTION According to an aspect of the present invention, there is provided a rotary engine having pistons, the rotary engine including: a stator in which an air inhalation hole and a combustion gas exhaust hole are formed; a rotor installed at the stator to freely rotate; at least one cylinder formed in the rotor and corresponding to an air inhalation hole and a combustion gas exhaust hole; at least one piston installed inside the cylinder so that a linear reciprocating motion can be made in such a way that air can be inhaled from the air inhalation hole by reducing pressure of an inside of the cylinder and the combustion gas can be exhausted through the combustion gas exhaust hole by pressurizing the inside of the cylinders; a fuel supply device installed at the stator and supplying a fuel to the inside of the cylinder; an ignition device installed at the stator and igniting the fuel supplied together with air inhaled into the cylinder; a power conversion device converting a descending expansion motion of the piston caused by an explosive force of the fuel inside the cylinder into a rotation motion of the rotation portion; and a piston ascending and descending induction device inducing a forcible ascending exhaustion motion and a forcible descending inhalation motion of the piston using a rotative force of the rotator.

The stator may include: a housing in which a rotation space in which the rotor can rotate is provided; and a front cover and a rear cover installed to cover the front and rear sides of the housing using a fixture so that the front cover and the rear cover can be attached to and detached from the front and rear sides of the housing, respectively, and the front cover and the rear cover sealing the rotation space using a sealing member, and the rotor may include: a rotation shaft whose both ends perforating the front cover and the rear cover and a spline being formed in the middle of the rotation shaft; and a cylindrical rotation portion in which three cylinders that are obliquely disposed to be inclined with a predetermined angle from a rotation center of the rotation shaft are installed on the circumferential surface of the rotation portion at equal angles, and wherein the piston is installed in the three cylinders, respectively, which are disposed at equal angles based on the rotation shaft of the rotation portion, so that the piston can ascend and descend freely.

The power conversion device may include: a piston rod whose one end being connected to a head pin of the piston so that the piston rod can be freely pivoted around the head pin at a predetermined angle; an interlocking shaft rod being hinge-coupled to the other end of the piston rod and having a protruding shape to a predetermined length from the rotor; and long groove members installed in the front and rear of the rotation portion, respectively, so that the long groove members can be attached to and detached from the rotation portion using the fixture, the long groove members being inclined at a predetermined angle with respect to an ascending and descending direction of the cylinder and in which a long groove for respectively guiding the both ends of the interlocking shaft rod is formed.

The piston ascending and descending induction device may include a piston ascending and descending guide groove installed in the front cover and the rear cover, so as to guide each of the both ends of the interlocking shaft rod and having an elliptical track in which a long shaft distant from the rotation shaft and a short shaft close to the rotation shaft are repeatedly rotated.

The elliptical track of the piston ascending and descending guide groove may include: a piston descending expansion section in which the piston is descended so that a rotative force of the rotation portion can be generated by an explosive force of a fuel from a first TDC (top dead center) to a first BDC (bottom dead center) after ignition; a piston ascending exhaustion section in which the piston is forcibly ascended so that a fuel gas can be forcibly exhausted from the first BDC to a second TDC; a piston descending inhalation section in which the piston is forcibly descended so that air can be inhaled from the second TDC to a second BDC; and a piston ascending pressurization section in which the piston is forcibly ascended so that air can be pressurized from the second BDC to the first TDC.

When a plurality of cylinders is installed at the rotor, the rotary engine may further include a cylinder sealing device sealing respective cylinders, and the cylinder sealing device may include: a sealing plate installed in a sealing groove formed on the circumference of the rotation portion to extend in a circumferential direction by a restoration force of the spring; and a pressure transmission tube transmitting the air pressure inside the cylinder to the sealing groove during fuel explosion and assisting circumferential extension of the sealing plate.

ADVANTAGEOUS EFFECTS

As described above, in the rotary engine having a plurality of pistons according to the present invention, mechanical efficiency, driving property and durability of the rotary engine are greatly improved, shock, friction, noise, and vibration are reduced so that the rotary engine can be manufactured using various materials, such as ceramics. The structure of the rotary engine is comparatively simple since the number of components of the rotary engine is reduced, repair or maintenance of the rotary engine is easy, ultra-miniaturization and high output of the rotary engine can be implemented, full combustion is performed and the rotary engine is environment friendly, the inhalation of sufficient air and sufficient combustion gas during a low-speed or high-speed rotation, an operating performance is excellent, and rigid sealing between the rotation portion and each cylinder is possible so that an excellent mechanical performance can be obtained.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a rotary engine having pistons according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of the components of the rotary engine of FIG. 1 , according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view taken along a line M-Il of FIG. 1 , according to an embodiment of the present invention.

FIG. 4 is a cross-sectional view taken along a line IV-IV of FIG. 1 , according to an embodiment of the present invention.

FIG. 5 is an enlarged cross-sectional view of one of the pistons of FIG. 3 during a fuel explosion, according to an embodiment of the present invention.

FIG. 6 is a conceptual view illustrating the state where one of the pistons moves in a guide groove of FIG. 2, according to an embodiment of the present invention.

FIG. 7 is a perspective view illustrating an operating state of a cylinder sealing device of FIG. 5, according to an embodiment of the present invention.

MODE OF THE INVENTION

The present invention will now be described more fully with reference to the accompanying drawings, in which an exemplary embodiment of the invention are shown. Firstly, referring to FIGS. 1 through 4, a rotary engine according to an embodiment of the present invention includes a stator 1 , a rotor 2, three cylinders 3, a plurality of pistons 4, a fuel supply device 5, an ignition device 6, a plurality of power conversion devices 7, and piston ascending and descending induction devices 8.

In the present embodiment, as illustrated in FIG. 2, the stator 1 is in a non-operating state based on the rotor 2 and includes a housing 9, a front cover 10, and a rear cover 11.

In detail, a rotation space in which the rotor 2 can rotate is provided inside the housing 9 of the stator 1 , an air inhalation hole 9a is formed in one side of a lower inner portion of the housing 9 and a combustion gas exhaust hole 9b is formed in another side of the lower inner portion of the housing 9, and the fuel supply device 5 and the ignition device 6, which will be described later, are formed in an upper portion of the housing 9.

In addition, the front cover 10 and the rear cover 11 are installed to cover the front and rear sides of the housing 9 using a plurality of fixtures 12 such as bolts or screws, so that the front cover 10 and the rear cover 11 can be attached to and detached from the front and rear sides of the housing 9, respectively, and the front cover 10 and the rear cover 11 seal the rotation space of the housing 9 using sealing members 13, such as gaskets, installed between the housing 9 and the front cover 10 or the rear cover 11. As illustrated in FIG. 2, the rotor 2 is installed to freely rotate in the rotation space of the housing 9 of the stator 1 and includes a rotation shaft 14 and a rotation portion 15.

In detail, both ends of the rotation shaft 14 protrude from the front cover 10 and the rear cover 11 , and a spline is formed in the middle of the rotation shaft 14 so that the spline is key-coupled to the rotation portion 15 and is rotated.

In addition, as illustrated in FIGS. 2 and 3, the rotation portion 15 is key-coupled to the spline of the rotation shaft 14 and has a cylindrical shape in which three cylinders

3, which are obliquely disposed to be inclined with a predetermined angle (at least 0-90 degrees) from the rotation center of the rotation shaft 14, are formed in the circumferential surface of the rotation portion 15 at equal angles from each other.

In detail, the three cylinders 3 are formed in the rotation portion 15 of the rotor 2 to correspond to the air inhalation hole 9a and the combustion gas exhaust hole 9b that are formed in the housing 9. In addition, the pistons 4 are installed inside the three cylinders 3 so that a linear reciprocating motion can be made in such a way that air can be inhaled through the air inhalation hole 9a by reducing pressure in the inside of the three cylinders 3 and a combustion gas can be exhausted through the combustion gas exhaust hole 9b by pressurizing the inside of the three cylinders 3. The pistons 4 are installed in the three cylinders 3 that are disposed at equal angles from each other with respect to the rotation shaft 14 of the rotation portion 15 so that the pistons 4 can ascend and descend freely within the three cylinders 3.

The fuel supply device 5 is installed at one side of the upper portion of the housing 9 of the stator 1 and supplies fuel to the inside of the three cylinders 3. Preferably, as illustrated in FIGS. 3 and 5, an injector, which is formed in the upper portion of the housing 9 of the stator 1 and sprays fuel at a high pressure into a combustion space full of air through a nozzle, may be used as the fuel supply device 5.

In addition, the ignition device 6 is installed at another side of the upper portion of the housing 9 of the stator 1 and ignites the supplied fuel mixed with the air in the three cylinders 3. Preferably, an electrical ignition device for generating an electrical spark may be used as the ignition device 6, as illustrated in FIGS. 3 and 5.

In the present embodiment, the functions of the fuel supply device 5 and the ignition device 6 are already well-known to one skilled the art and the functions are widely used and may be easily modified within the scope of the invention. As illustrated in FIGS. 2, 3, and 5, the power conversion device 7 converts a descending expansion motion of the piston 4 that is caused by an explosive force F of the fuel inside a cylinder 3, which is one of the cylinders 3, into a rotation motion of the rotation portion 15. The power conversion device 7 includes a piston rod 16, an interlocking shaft rod 17, and a long groove member 18.

In detail, one end of the piston rod 16 is connected to a head pin 19 of a piston 4, which is one of the pistons 4, so that the piston rod 16 can be freely pivoted around the head pin 19 at a predetermined angle, and the other end of the piston rod 16 is hinge-coupled to the interlocking shaft rod 17 so that the piston rod 16 connects the piston 4 and the interlocking shaft rod 17 and constitutes a joint.

In addition, the interlocking shaft rod 17 is coupled to the other end of the piston rod 16 so that the interlocking shaft rod 17 can freely rotate, and the interlocking shaft rod 17 has a predetermined length that is longer than the width of the rotation portion 15 such that both ends of the interlocking shaft rod protrude the rotation portion 15. In addition, the long groove member 18 is installed in the front and rear of the rotation portion 15, respectively, so that the long groove member 18 can be attached to and detached from the rotation portion 15 using a fixture 12, which is one of the fixtures 12, such as a bolt or screw. The long groove member 18 is inclined at a predetermined angle corresponding to an ascending and descending direction of the cylinder 3, and a long groove 20 for respectively guiding both ends of the interlocking shaft rod 17 is formed in the long groove member 18. In the present embodiment, preferably, the lengthwise direction of the long groove 20 is directed toward the rotation shaft 14.

Thus, as illustrated in FIG. 5, when the fuel that is mixed with air explodes in the combustion space, a force in an inclined direction of the piston 4, that is, an explosive force F, is generated. However, the explosive force F is converted into a descending force S and a rotative force K using the interlocking shaft rod 17 that is guided by the long groove 20, and due to the rotative force K, a rotation moment is generated by a distance multiplied with the center of the rotation shaft 14 so that a descending motion of the piston 4 due to the explosive force F can be converted into a rotative motion of the rotation portion 15.

The piston ascending and descending induction device 8 induces a forcible ascending exhaustion motion and a forcible descending inhalation motion of the piston 4 using a rotative force of the rotator 2. As illustrated in FIGS. 2, 3, and 6, two piston ascending and descending induction devices 8 are respectively installed in the front cover 10 and the rear cover 11 , respectively, so as to guide each of both ends of the interlocking shaft rod 17 and each piston ascending and descending induction device 8 includes a piston ascending and descending guide groove 22 having an elliptical track 21 , in which a long shaft distant from the rotation shaft 14 and a short shaft close to the rotation shaft 14 are repeatedly rotated.

As illustrated in FIG. 6, the elliptical track 21 of the piston ascending and descending guide groove 22 sequentially includes a piston descending expansion section (A-B), a piston ascending exhaustion section (B-C), a piston descending inhalation section (C-D)₁ and a piston ascending pressurization section (D-A).

In detail, as illustrated in FIG. 6 and in FIG. 3, in the piston descending expansion section A-B, the piston 4 is descended by the explosive force F of a fuel so that a rotative force of the rotation portion 15 can be generated by the explosive force F of the fuel during the phase from a first top dead center (TDC) position (A) to a first bottom dead center (BDC) position (B) after ignition.

Subsequently, in the piston ascending exhaustion section B-C, the piston 4 is forcibly ascended so that a fuel gas can be forcibly exhausted during the phase from the first BDC position (B) to a second TDC position (C).

In this case, the force used to forcibly ascend the piston 4 depends on an inertial force of the rotating portion 15 generated in the piston descending expansion section A-B and the explosive force F of another adjacent piston 4.

Subsequently, in the piston descending inhalation section (C-D), the piston 4 is forcibly descended so that air can be inhaled during the phase from the second TDC position (C) to a second BDC position (D). Even in this case, the force used to forcibly descend the piston 4 depends on an inertial force of the rotation portion 15 generated in the piston descending expansion section (A-B) and the explosive force F of another adjacent piston 4.

Subsequently, in the piston ascending pressurization section (D-A), the piston 4 is forcibly ascended so that air can be pressurized during the phase from the second BDC position (D) to the first TDC position (A).

Even in this case, the force used to forcibly ascend the piston 4 depends on an inertial force of the rotation portion 15 generated in the piston descending expansion section (A-B) and the explosive force of another adjacent piston 4.

Subsequently, as long as the fuel is constantly supplied and ignition is performed, the interlocking shaft rod 17 repeatedly rotates sequentially along the above-described piston descending expansion section (A-B), the piston ascending exhaustion section

(B-C), the piston descending inhalation section (C-D), and the piston ascending pressurization section (D-A). Hence, in an operation of the rotary engine having pistons 4 along with the interlocking shaft rod 17 that is guided by the elliptical track 21 of the piston ascending and descending guide groove 22 and rotates along an elliptical track 21 , as illustrated in

FIGS. 3 and 6 and in the above-described piston descending expansion section (A-B), the fuel and air inside the combustion space are ignited by the ignition device 16, and due to the explosive force F, the rotation portion 15 is rotated by a rotative force K and simultaneously, the piston 4 is descended by the interlocking shaft rod 17 that is guided by the long groove 20 and the elliptical track 21.

Subsequently, in the above-described piston ascending exhaustion section (B-C), due to the inertial force of the rotation portion 15 generated in the piston descending expansion section (A-B) and the explosive force of another adjacent piston 4, the piston

4 is forcibly guided by the long groove 20 and the elliptical track 21 and is forcibly ascended so that the combustion gas can be forcibly exhausted.

In this case, the pressure inside the cylinder is increased by the ascended piston

4, and as in the lower right piston 4 of FIG. 3, when the combustion gas due to the increased pressure passes through the combustion gas exhaust hole 9b, most of the combustion gas can be exhausted to the outside.

Subsequently, in the above-described piston descending inhalation section (C-D), due to the inertial force of the rotation portion 15 generated in the piston descending expansion section (A-B) and the explosive force of another adjacent piston 4, the piston 4, for which exhaust of the combustion gas is completed, is forcibly guided by the long groove 20 and the elliptical track 21 and is forcibly descended so that air can be inhaled.

In this case, the pressure inside the cylinder 3 is increased by the descended piston 4, and as in the lower left piston 4 of FIG. 3, when the air inside the cylinder 3 of the reduced pressure passes through the air inhalation hole 9a, fresh air can be inhaled from the outside.

Subsequently, in the above-described piston ascending pressurization section

(D-A), due to the inertial force of the rotation portion 15 generated in the piston descending expansion section (A-B) and the explosive force of another adjacent piston 4, the piston 4, for which exhaust of the combustion gas is completed, is forcibly guided by the long groove 20 and the elliptical track 21 and is forcibly ascended so that the inhaled air can be forcibly pressurized.

In this case, the pressure inside the cylinder 3 is increased by the ascended piston 4, and as in the upper piston 4 of FIG. 3, the air inhaled into the cylinder 3 can be sufficiently pressurized for an easier explosion.

Subsequently, when the piston 4 reaches the first TDC (A) position, the fuel is sprayed into the cylinder 3 from the fuel supply device 5 and the ignition device 6 ignites the pressurized air and fuel, and explodes the pressurized air and fuel. Then, the piston 4 repeatedly performs the above-described piston descending expansion process, the piston ascending exhaustion process, the piston descending inhalation process, the piston ascending pressurization process and explosion process so that the rotation portion 15 can be constantly rotated.

As illustrated in FIGS. 5 and 7, the rotary engine having pistons 4 further includes cylinder sealing devices 23 for sealing the respective three cylinders 3, wherein each cylinder sealing device 23 includes a sealing plate 24 and pressure transmission tubes 25.

In detail, the sealing plate 24 is installed in a sealing groove 26 formed in the circumference of the rotation portion 15 to extend in a circumferential direction by a restoration force of the spring 27, and the pressure transmission tubes 25 transmit the air pressure inside the cylinder 3 to the sealing groove 26 during a fuel explosion and assist the circumferential extension of the sealing plate 24. Thus, as illustrated in FIG. 7, the sealing plate 24 is closely attached to the housing 9 by the restoration force of the spring 27 and seals the three cylinders 3 so that high-pressure fuel gas generated during an explosion cannot leak toward another cylinders 3 or to the outside. Furthermore, since the high-pressure combustion gas during an explosion is transmitted to the sealing groove 26 through the pressure transmission tube 25 and assist the sealing plate 24 to be closely attached to the housing 9, a more rigid sealing is possible, and if pressure of the combustion gas is reduced after an explosion, the assisting action is reduced by the pressure of the air inside the cylinder 3 so that the rotating portion 15 can be smoothly rotated.

As illustrated in FIG. 1, in the rotary engine having pistons 4 according to the present invention, it is obvious to one skilled in the art that a controller 28 for controlling the fuel supply device 5 and the ignition device 6 can be installed. In detail, a sensor 29 for sensing a rotation angle is installed at the rotation portion 15 or the rotation shaft 14, and the controller 28 applies a control signal to the fuel supply device 5 and the ignition device 6, respectively, in response to a signal applied from the sensor 29 with respect to a rotation angle of the rotation shaft 14. Thus, in the rotary engine having pistons according to the present invention, a plurality of components having complicated shapes, such as a crank shaft, a crank rod, an inhalation valve, and an exhaustion valve, is not necessary, the explosive force of the piston can be divergently guided to the long groove and the elliptical track, and a plurality of pistons is installed at one rotation portion such that shock or friction is small, noise and vibration are reduced, mechanical durability and efficiency are greatly improved and the rotary engine can be sufficiently used in a material that is weak to shock, such as ceramics.

In addition, in the rotary engine having pistons according to the present invention, the size of the rotary engine can be reduced, the structure of the rotary engine is comparatively simple and repair or maintenance is easy, the combustion gas is completely exhausted, air is completely inhaled and driving property and efficiency are greatly improved, full combustion is performed, the rotary engine is environment friendly, the inhalation of the sufficient air and the sufficient combustion gas during low-speed or high-speed rotation, effective and long-term sealing between the rotation portion and each cylinder is easily performed and the rotary engine can be easily implemented.

The above-described embodiments are just illustrative and it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. Accordingly, the ultimate technical protection scope of the present invention will be defined by the technical spirit of the invention described in the following claims.

Claims

1. A rotary engine having pistons: a stator in which an air inhalation hole and a combustion gas exhaust hole are formed; a rotor installed at the stator to freely rotate; at least one cylinder formed in the rotor and corresponding to an air inhalation hole and a combustion gas exhaust hole; at least one piston installed inside the cylinder so that a linear reciprocating motion can be made in such a way that air can be inhaled from the air inhalation hole by reducing pressure of an inside of the cylinder and the combustion gas can be exhausted through the combustion gas exhaust hole by pressurizing the inside of the cylinders; a fuel supply device installed at the stator and supplying a fuel to the inside of the cylinder; an ignition device installed at the stator and igniting the fuel supplied together with air inhaled into the cylinder; a power conversion device converting a descending expansion motion of the piston caused by an explosive force of the fuel inside the cylinder into a rotation motion of the rotation portion; and a piston ascending and descending induction device inducing a forcible ascending exhaustion motion and a forcible descending inhalation motion of the piston using a rotative force of the rotator.

2. The rotary engine of claim 1 , wherein the stator comprises: a housing in which a rotation space in which the rotor can rotate is provided; and a front cover and a rear cover installed to cover the front and rear sides of the housing using a fixture so that the front cover and the rear cover can be attached to and detached from the front and rear sides of the housing, respectively, and the front cover and the rear cover sealing the rotation space using a sealing member, and wherein the rotor comprises: a rotation shaft whose both ends perforating the front cover and the rear cover and a spline being formed in the middle of the rotation shaft; and a cylindrical rotation portion in which three cylinders that are obliquely disposed to be inclined with a predetermined angle from a rotation center of the rotation shaft are installed on the circumferential surface of the rotation portion at equal angles, and wherein the piston is installed in the three cylinders, respectively, which are disposed at equal angles based on the rotation shaft of the rotation portion, so that the piston can ascend and descend freely.

3. The rotary engine of claim 2, wherein the power conversion device comprises: a piston rod whose one end being connected to a head pin of the piston so that the piston rod can be freely pivoted around the head pin at a predetermined angle; an interlocking shaft rod being hinge-coupled to the other end of the piston rod and having a protruding shape to a predetermined length from the rotor; and long groove members installed in the front and rear of the rotation portion, respectively, so that the long groove members can be attached to and detached from the rotation portion using the fixture, the long groove members being inclined at a predetermined angle with respect to an ascending and descending direction of the cylinder and in which a long groove for respectively guiding the both ends of the interlocking shaft rod is formed.

4. The rotary engine of claim 3, wherein the piston ascending and descending induction device comprises a piston ascending and descending guide groove installed in the front cover and the rear cover, so as to guide each of the both ends of the interlocking shaft rod and having an elliptical track in which a long shaft distant from the rotation shaft and a short shaft close to the rotation shaft are repeatedly rotated.

5. The rotary engine of claim 4, wherein the elliptical track of the piston ascending and descending guide groove comprises: a piston descending expansion section in which the piston is descended so that a rotative force of the rotation portion can be generated by an explosive force of a fuel from a first TDC (top dead center) to a first BDC (bottom dead center) after ignition; a piston ascending exhaustion section in which the piston is forcibly ascended so that a fuel gas can be forcibly exhausted from the first BDC to a second TDC; a piston descending inhalation section in which the piston is forcibly descended so that air can be inhaled from the second TDC to a second BDC; and a piston ascending pressurization section in which the piston is forcibly ascended so that air can be pressurized from the second BDC to the first TDC.

6. The rotary engine of claim 1 , wherein, when a plurality of cylinders is installed at the rotor, the rotary engine further comprises a cylinder sealing device sealing respective cylinders, and wherein the cylinder sealing device comprises: a sealing plate installed in a sealing groove formed on the circumference of the rotation portion to extend in a circumferential direction by a restoration force of the spring; and a pressure transmission tube transmitting the air pressure inside the cylinder to the sealing groove during fuel explosion and assisting circumferential extension of the sealing plate.

7. The rotary engine of claim 1 , further comprising: a sensor sensing a rotation angle of the rotor; and a controller applying a control signal to the fuel supply device and the ignition device, respectively, in response to a signal applied from the sensor with respect to a rotation angle of the rotation shaft.