Title:
Rotary positive displacement engine
Kind Code:
A1


Abstract:
The rotary positive displacement engine includes a compressor housing having a compression chamber therein and a rotor housing having a rotor chamber therein. The rotor housing and compressor housing are in fluid communication and define a main housing having a first end plate, an opposing second end plate, and a center divider plate interposed therebetween, wherein the first and second end, and center divider plates are connected to the main housing. An output member is rotatably supported within the main housing and extends axially therefrom. A compressor is disposed within the compressor chamber and is mounted on the output member. An engine rotor is disposed within the rotor chamber and is mounted on the output member. An engine rotor working end portion defines a combustion chamber, wherein fuel is ignited to rotate the engine rotor, which, in turn, rotates the output shaft.



Inventors:
Gardner, Edmond J. (Elkton, MD, US)
Application Number:
10/996436
Publication Date:
06/08/2006
Filing Date:
11/26/2004
Primary Class:
Other Classes:
417/410.1
International Classes:
F04B35/04; F04B17/00
View Patent Images:
Related US Applications:



Primary Examiner:
TRIEU, THAI BA
Attorney, Agent or Firm:
Richard C. Litman (Alexandria, VA, US)
Claims:
I claim:

1. A rotary positive displacement engine, comprising: a first end plate, an opposing second end plate, and a center divider plate interposed therebetween; an output member rotatably supported within the end plates and the center divider plate and extending axially from the first and second end plates; a compressor housing mounted between the first plate and the center divider plate, the compressor housing having inner and outer surfaces, the inner surface defining a compression chamber therein; a compressor disposed within the compressor chamber and mounted on the output member; a rotor housing mounted between the center divider plate and the second end plate and having an inner and outer surfaces, the inner surface defining a rotor chamber therein, the rotor housing and the compressor housing being axially aligned and being in fluid communication to permit fluid flow therebetween; an engine rotor disposed within the rotor chamber and mounted on the output member, the engine rotor having at least one working end portion defining a combustion chamber; whereby a working fluid compressed by the compressor in the compression chamber is injected into the combustion chamber of the engine rotor for ignition thereof, thereby rotating the engine rotor and the output member about a central longitudinal axis.

2. The rotary positive displacement engine according to claim 1, further comprising an air and fuel intake port disposed in an upper portion of the compressor housing.

3. The rotary positive displacement engine according to claim 1, wherein a channel is disposed in a lower portion of the compressor housing, the channel being in communication with the compression chamber for storing the compressed working fluid.

4. The rotary positive displacement engine according to claim 3, wherein the centered divider plate has a metering port in communication with the channel.

5. The rotary positive displacement engine according to claim 4, wherein the engine rotor has a rotor intake port in communication with the metering port for injecting the compressed working fluid into the combustion chamber for ignition thereof.

6. The rotary positive displacement engine according to claim 1, further comprising an ignition port having an ignition device operatively connected thereto for igniting the working fluid in the combustion chamber, the ignition port being disposed at the lower portion of the rotor housing.

7. The rotary positive displacement engine according to claim 1, further comprising an exhaust port disposed in an upper portion of the rotor housing for exhausting gases out of the combustion chamber.

8. The rotary positive displacement engine according to claim 1, wherein the compressor is an orbiting scroll compressor.

9. The rotary positive displacement engine according to claim 1, wherein the compressor is a twin-screw compressor.

10. A rotary positive displacement engine, comprising: a main housing having a compressor side defined by a compressor housing and a rotor side defined by a rotor housing; the compressor housing having an inner surface, an outer surface, an inlet port, and discharge port, the inner surface defining a compression chamber therein, the rotor housing having an inner surface, outer surface, and an exhaust port, the inner surface defining a rotor chamber therein, the compressor housing being in communication with the rotor housing to permit fluid flow thereto; a channel disposed in lower portion of the compressor housing for storing compressed working fluid; a center divider plate interposed between the compressor housing and the rotor housing, the center divider plate having a metering port in communication with the channel for injecting the working fluid into the rotor side; an output shaft rotatably supported within the main housing and extending axially from the main housing; a compressor disposed within the compressor chamber, the compressor being rotatably mounted to the output shaft for compressing the working fluid; an engine rotor disposed within the rotor chamber, the engine rotor being rotatably mounted to the output shaft, the engine rotor having an inner circumference concentrically mounted to the output shaft for rational movement about a longitudinal axis and an outer circumference having at least one working end portion extending radially outward therefrom; and wherein the working fluid is compressed by the compressor in the compression chamber and is injected into the working end portion of the engine rotor for ignition thereof, and wherein the ignition of the working fluid causes expansion of gases, which rotates the engine rotor and the output member about the central longitudinal axis.

11. The rotary positive displacement engine according to claim 10, wherein the at least one working end portion includes a leading wall, a trailing wall, an opposing first and opposing second end portions, and recessed wall, the first end portion defining a first end wall, the second end portion defining a rotor intake port, the trailing wall having a greater surface area than the leading wall.

12. The rotary positive displacement engine according to claim 11, wherein a combustion chamber is defined between the leading wall, the trailing wall, first end wall, and recessed wall of the at least one working end portion and is further defined by rotor side portion of the center divider plate.

13. The rotary positive displacement engine according to claim 12, wherein the rotor intake port is in communication with the metering port and the combustion chamber.

14. The rotary positive displacement engine according to claim 13, wherein the at least one working end portion includes a second working end portion disposed on the rotor engine.

15. The rotary positive displacement engine according to claim 14, wherein the at least one working end portion and the second working end portion are oriented approximately 180° apart with respect to each other on the engine rotor.

16. The rotary positive displacement engine according to claim 10, further comprising a rear thrust restrictor configured for sealing engagement with the engine rotor.

17. The rotary positive displacement engine according to claim 10, wherein the working fluid is selected from the group consisting of air, fuel and air-fuel mixture.

18. The rotary positive displacement engine according to claim 10, wherein the at least one working end portion includes a rotor tip in continuous contact with inner surface of the rotor housing for sealing engagement therewith.

19. A method for imparting rotational energy to an output shaft from a working fluid, comprising the steps of: providing an engine comprising a main housing having a rotor housing with an engine rotor and a compressor housing with a compressor rotor; rotatably mounting the engine rotor and the compressor rotor to an output shaft extending axially from the main housing for producing rotational energy thereof; rotating the compressor rotor to a first position so as to draw working fluid into a compression chamber through an intake port disposed in the compressor housing; rotating the compressor rotor to a second position so as to substantially seal the compression chamber between compressor vanes and inner surface of the compressor housing; rotating the compressor chamber to a third position so as to compress the compression chamber and to discharge the compressed working fluid into a channel formed in the lower portion of the compressor housing; rotating the engine rotor to a first position to create a slightly negative charge in a combustion chamber disposed therein; rotating the engine rotor to a second position so as to align a rotor intake port with a metering port, which is in communication with the channel; injecting the working fluid from the metering port into the rotor intake port so as to charge the combustion chamber with the compressed working fluid; rotating the charged combustion chamber to a third position so as to substantially seal the combustion chamber and to position the combustion chamber adjacent to the ignition device disposed in lower portion of rotor housing; igniting the working fluid within the combustion chamber so as to form expanding gases within the combustion chamber to rotate the engine rotor; rotating the combustion chamber to a fourth position to increase the volume of the combustion chamber as the gases continue to expand; and rotating the combustion chamber to a fifth position so as to exhaust the gases through an exhaust port disposed in upper portion of the rotor housing.

Description:

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to internal combustion engines, and in particular, to a rotary positive displacement internal combustion engine.

2. Description of the Related Art

Reciprocating internal combustion engines are typically reciprocating four or two stroke spark ignition or compression ignition engines. The conventional reciprocating piston engine performs a four-phase combustion cycle within the same cylinder. For example, intake, compression, power and exhaust cycles are carried out in a single cylinder, which results is a large amount of thermal energy being taken away by waste gases as high-temperature exhaust. Additionally, there are losses in component forces as the power acting on the top to the piston is transmitted through the piston and connecting rod to the crankshaft. Moreover, operation of the intake and exhaust valves consumes engine power, and there are inertia losses as the valves and pistons are reciprocating.

Furthermore, reciprocating engines have inherent static an dynamic balancing problems due in part to vibration from the reversal of direction of the piston upon completion of each phase of the combustion cycle.

Rotary engines, such as the Wankel rotary engine, have been have been given consideration as an internal combustion engine that solves some of the inherent problems with reciprocating engines. The rotary engine has demonstrated some advantages over reciprocating piston engines, including smaller volumes, less inertia losses, reduced vibration, fewer components as compared with reciprocating piston-type engines, superior breathing, no valves because the rotor and its seals serve as valves, low-octane fuel requirement, low emissions, and no reciprocating imbalance. In addition, rotary engines generally exhibit an increased power-to-weight ratio due to a reduction of friction and an increase in efficiency derived from the rotary engine.

While rotary engines have demonstrated certain advantages over the reciprocating engine, there remains a need for an improved engine that has high power-to-mass ratio, a high efficiency and is relatively easy to manufacture. Thus, a rotary positive displacement engine solving the aforementioned problems is desired.

SUMMARY OF THE INVENTION

The rotary positive displacement engine includes a main housing having a compressor side, which is defined by a compressor housing, and a rotor side, which is defined by a rotor housing. An output shaft is rotatably supported within the main housing and extends axially from the main housing.

The compressor housing has an inner surface, an outer surface, an inlet port, and discharge port. The inner surface of the compressor housing is configured to define a compression chamber therein. A compressor is disposed within the compressor chamber and is rotatably mounted to the output shaft for compressing the working fluid. A channel is disposed in the lower portion of the compression chamber for storing the compressed working fluid.

A center divider plate is interposed between the compressor housing and the rotor housing. The center divider plate includes a metering port in communication with the channel for injecting the working fluid into the rotor side.

The rotor housing has an inner surface, an outer surface, and an exhaust port. The inner surface of the rotor housing is configured to define a rotor chamber therein. The compressor housing is in communication with the rotor housing so that a working fluid can flow from the compressor side to the rotor side. An engine rotor is disposed within the rotor chamber and is rotatably mounted to the output shaft. The engine rotor has an inner circumference concentrically mounted to the output shaft for rotational movement about a longitudinal axis, and an outer circumference that has at least one working end portion extending radially outward therefrom.

During operation of the rotary positive displacement engine, the working fluid is compressed by the compressor in the compression chamber and is injected into the working end portion of the engine rotor for ignition thereof, which, in turn, causes rotation of the engine rotor and the output shaft about the central longitudinal axis.

These and other features of the present invention will become readily apparent upon consideration of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a vertical section view of a rotary positive displacement engine according to the present invention as seen from the side.

FIG. 2 is an exploded view of the rotary positive displacement engine of FIG. 1.

FIG. 3 is a vertical section view of the engine of FIG. 1 as seen from an end, illustrating the interrelationship of the parts of the multiple vane compression chambers.

FIG. 4 is a section view of the engine of FIG. 1, further illustrating the interrelationship of the parts of the combustion chamber.

FIG. 5 is a diagrammatic front view of a center divider plate of the rotary positive displacement engine of FIG. 1.

FIGS. 6A, 6B, 6C and 6D are diagrammatic section views showing the operating sequence of the rotary positive displacement engine of FIG. 1.

Similar reference characters denote corresponding features consistently throughout the attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to a rotary positive displacement engine, indicated generally at 10 in the drawings. Referring to FIGS. 1-5, the rotary positive displacement engine 10 includes a compressor housing 20 joined to a rotor housing 60 to define a main housing 11 having a compressor side and a rotor side. The compressor housing 20 is in fluid communication with the rotor housing 60 to permit fluid flow therebetween, such that a working fluid, such as an air-fuel mixture, flows from the compressor side to the rotor side.

The main housing 11 includes a first end section 11a having a first end wall or plate 14. Opposite first end section. 11a is second end section 11b having a second end wall or plate 16. Interposed between the first and second end sections 11a and 11b, respectively, is an intermediate section 11c having a center divider wall or plate 40. The first and second end plates 14 and 16, respectively, and the center divider plate 40 are connected to the rotor housing 60 and compressor housing 20 by fasteners (not shown). The fasteners are not shown for clarity in the drawings; however, any fastener, such as a nut and bolt assembly, screws, rivets, bolts, pins, or dowels, can be employed as fasteners. Alternatively, the compressor housing 20, center divider plate 40, and rotor housing 60 can be integrally joined together by welding or the like.

An output member 12, such as, for example, a shaft, an axle, a spindle, or a rod, is rotatably supported within the main housing 11 and extends axially outward from the main housing 11 along longitudinal axis A. Preferably, the output shaft 12 extends axially from the first and second end plates 14 and 16, respectively, for operatively coupling objects thereto. The output shaft 12 is configured to concentrically mount the engine rotor 70 and compressor rotor 52 thereon for providing rotational energy thereof. Bearings 108, 110, and 112 are employed to rotatably mount the output shaft 12 in first and second end plates 14 and 16, and center divider plate 40. At least one oil passage or port 48 is disposed in the main housing 11 for lubricating various engine components. Preferably, at least one oil port 48 extends from the outer surface of the center divider plate 40 to the output shaft 12 for lubricating the various components of the rotary positive displacement engine 10, including bearing 110 and compressor vanes 54.

The rotor housing 60 has an outer surface 61 and inner surface 62. The inner surface 62 of the rotor housing 60 defines a rotor chamber 80 having a generally cylindrical or circular shape. The engine rotor 70 is disposed within the rotor chamber 80 and is coupled to the output shaft 12 by a suitable mounting means, such as fastener 102. The fastener 102 depicted in the drawings is a key and key seat assembly 104; however, a pin, sleeves, or grip springs can be employed too. Alternatively, the engine rotor 70 can be press-fit onto the output shaft 12 for rotational movement therewith.

The upper portion 66 of the rotor housing 60 includes an exhaust port 64. The lower portion 68 of the rotor housing 60 includes an ignition port 88 and rear thrust restrictor 90. At least one ignition or spark device 100 is operatively connected to the ignition port 88 for igniting fuel within a combustion chamber 116. At least one spark plug or glow plug can be utilized as the spark device 100. The rear thrust restrictor 90 is pivotally connected to the rotor housing 60 at pivot joint 98 and is configured to sealably engage the engine rotor 70 to form a second seal or back pressure seal 84. The rear thrust restrictor 90 includes a lever arm 92 in cooperation with a biasing member 96 and spring 94 for adjusting the amount of pressure or force being applied to the engine rotor 70 by the back pressure seal 84. The spring 94 is interposed between the lever arm 92 and the biasing member 96.

The engine rotor 70 is rotatably mounted within the rotor housing 60. The engine rotor 70 has an inner circumference configured to concentrically mount to the output shaft 12 for rotary movement about longitudinal axis A and an outer circumference having a generally cylindrical or circular configuration. The rotor 70 includes at least one, and preferably more than one, working end portions 114. Each working end portion 114 extends radially inward from the outer circumference of the engine rotor 70, which is generally circular, cylindrical, elliptical or oval-shaped. The working end portions 114 are oriented adjacent to the inner surface 62 of rotor housing 60. The working end portions 114 include a leading wall 118, a trailing wall 120, a first end portion 122, a second end portion 124, and recessed wall 126. The combustion chambers 116 are disposed within the working end portion 114. The first end portion 122 is configured to define a first end wall. The second end portion 124 is configured to define a rotor intake port 128.

Each combustion chamber 116 is defined by leading wall 118, trailing wall 120, and first end portion 122 of the working end portion 114. The combustion chamber 116 is furthered defined by the rotor side portion 42 of the center divider plate 40 and inner surface 62 of the rotor housing 60. The trailing wall 120 slopes rearward gradually, having a greater surface area than the leading wall 118, so that the force of the explosion exerts greater pressure against the leading wall 118. The combustion chamber 116 is in communication with rotor intake port 128, which is defined by the second end portion 128, and extends axially into the rotor 70. The rotor intake port 128 is in communication with metering port 46, which is disposed in center divider plate 40.

As shown in FIGS. 1, 2 and 5, the metering port 46 is generally orientated in the lower portion of the center divider plate 40 and extends from compressor side portion 44 to rotor side portion 42 of the center divider plate 40. The rotor intake port 128 and the metering port 46 are constructed and arranged to align with each other for communication therebetween as the engine rotor 70 rotates about longitudinal axis A. A seal 56 is disposed on the rotor side potion 42 of the center divider plate 40 to provide a seal between rotor intake port 128 and metering port 46. Additionally, the metering port 46 is in communication with channel 32. The metering port 44 is configured so that compressed air-fuel mixture contained in channel 32 of the compressor housing 20 flows through the center divider plate 40 and into the rotor intake port 128 to charge the combustion chamber 116 for ignition thereof.

As shown in FIGS. 1-6D, the leading wall 118 further defines rotor tip 130, which is in continuous contact with inner surface 62 of the rotor housing 60 and is configured for sealing engagement therewith. A forward pressure seal or first seal 82 is disposed at the leading wall 118 for forming a seal between the rotor tip 130 and the inner surface 62 of the rotor housing 60. Alternatively, the forward pressure seal 82 can integrally extend from the leading wall 118 or the rotor tip 130 can define the forward pressure seal 82. The leading wall 118 and the trailing wall 120 are oriented with respect to each other so that a cam 132 is defined therebetween to operatively engage the rear thrust restrictor 90 as the engine rotor 70 rotates in a clockwise direction as indicated by arrow B.

The compressor housing 20 includes an outer surface 21 and an inner surface 22. The inner surface 22 of the compressor housing 20 has a generally cylindrical or circular shape and defines a compressor or compression chamber 24 therein. A compressor 50 is disposed within the compression chamber 24 and is rotatably mounted to the output shaft 12 for compressing a working fluid, such as a gas, air, fuel, liquid, fluid, or a combination thereof, such as, for example, a gas-fluid mixture or air-fuel mixture. The compressor 50 illustrated in the drawings is a typical rotary-van compressor having a compressor rotor 52 and a plurality of compressor vanes 54. The compressor rotor 52 is coupled to the output shaft 12 by fastener 102, such as key and key seat assembly 104. Additionally, a pin, sleeve, or grip springs can be employed. Alternatively, the compressor rotor 52 can be press-fitted onto the output shaft 12 for rotation movement thereon.

Compressor 50 is shown for illustrative purposes, the construction of the compressor not being critical, and any suitable compressor can be utilized that is capable of compressing an air-fuel mixture. For example, a rolling-piston compressor, a twin-screw compressor, an orbiting scroll compressor, or a centrifugal compressor can be utilized to compress the air-fuel mixture entering into the compression chamber through an inlet port 30.

As shown in FIGS. 1-5, the inlet or air and intake port 30 is disposed at the upper portion 26 of the compressor housing 20. The inlet port 30 is configured to permit fluid flow of a working fluid, such as, an air-fuel mixture, to be drawn into the compressor chamber 24, which is formed by the compressor vanes 54 and inner surface 22. A storage element 32, such as a channel, conduit, or trough, is disposed at the lower portion of the compressor housing for storing the compressed air-fuel mixture. The channel 32 stores the compressed air-fuel mixture, until the engine rotor 70 rotates the rotor intake port 128 into alignment with the metering port 46, whereupon the compressed air-fuel mixture passes through the metering port 46 and is injected into the combustion chamber 116. The channel 32 is in communication with the compression chamber 24 for storing the compressed working fluid.

The channel 32 has a generally concave or semi-circular shape, which is defined by a top wall 134, an arcuate or curved bottom wall 136, and two opposing sidewalls 138 and 140, respectively. The top wall 134 is further defined by the inner surface 22 of the compressor housing 20. At least one discharge port 34 is disposed in the top wall 134 of the channel 32 for discharging the compressed air-fuel mixture from the compression chamber 24 into the channel 32. The channel 32 is in communication with the metering port 46 so as to inject the compressed air-fuel mixture through the metering port 46 and into the combustion chamber 116 as the rotor intake port 128 rotates in alignment with the metering port 46.

FIGS. 6A-6D depict the operating sequence of the rotary positive displacement engine 10. As compressor rotor 52 rotates in a clockwise direction, as indicted by arrow B, the compressor vanes 54 slidably engage with inner surface 22 of the compressor housing 20 to form compression chamber 24 therebetween. Hence, the compressor vanes 54, the compressor rotor 52, and the inner surface 22 of the compressor housing 20 define the compression chamber 24. At first positioned indicated by a compression chamber 24a, the compression chamber 24 is increasing in volume as the compressor rotor 52 rotates clockwise. This increase in volume creates a negative pressure, which causes or induces the air-fuel mixture to enter the compression chamber 24a through the air and intake port 30.

The increase in volume continues until the compression chamber 24 occupies the second position indicated by a compression chamber 24b. At compression chamber 24b, the combustion chamber 24 begins to diminish in volume as rotation of compressor rotor 52 continues in a clockwise direction. As the volume of compression chamber 24 is reduced, the air-fuel mixture contained within the compression chamber 24 is compressed causing it to become heated. At the third position indicated at combustion chamber 24c, the compressed air-fuel mixture discharges from the compression chamber 24 though the discharge port 34 and into channel 32. As the compression chamber 24 continues to rotate clockwise pass the discharge port 34, the compression chamber 24 begins to increase its volume as indicated by the fourth position at compression chamber 24d, where the cycle is repeated again at compression chamber 24a.

On the rotor side of the rotary positive displacement engine 10, since the engine rotor 70 and the compressor rotor 52 are concentrically mounted to the output shaft 12, the engine rotor 70 is simultaneously rotating in a clockwise direction, as indicated by arrow B. At the first position, indicated by a compression chamber 116a, the compression chamber 116 is increasing in volume as the engine rotor 70 rotates clockwise. This increase in volume creates a negative pressure, which facilitates the charging of the combustion chamber 116. As the combustion chamber 116 rotates into the second position indicated by combustion chamber 116b, the rotor intake port rotates in alignment with the metering port 46. The rotor intake port 128 is in communication with the metering port 46 so that compressed air-fuel mixture from channel 32 is injected into the slightly negatively charged combustion chamber 116b. This charges the combustion chamber 116 for ignition.

At the third position indicated by combustion chamber 116c, the trailing wall 120 has cleared the metering port 46 and the combustion chamber 116 is ignited. The rapidly expanding gases generate a force, which propels the leading wall 118 in a clockwise direction. The rear thrust restrictor 90 forms a back pressure seal that substantially prevents the expanding gases from exiting or blowing pass the trailing wall 120. The expansion of ignited gases within the combustion chamber 116c tends to expand with more force against the leading wall 118 of the combustion chamber 116, which rotates the engine rotor 70 in a clockwise direction along the direction indicated by arrow B. Moreover, as the volume of the combustion chamber 116 increases as the engine rotor 70 rotates about longitudinal axis A at the fourth positioned indicated at combustion chamber 116d, the rapidly expanding gases tends to further encourage rotation of the leading wall 118 in the clockwise direction.

The expansion of the combusting gases continues in combustion chamber 116d, until the combustion chamber 116 is rotated into the fifth position indicated by a combustion chamber 116e. At combustion chamber 116e, the expansion of combusting gases initiates the evacuation of combustion chamber 116e by allowing the expanding gases to follow the path of least resistance, which is out the exhaust port 64 that is in communication with the combustion chamber 116e.

The rotation of a leading wall 118 of one of the combustion chamber 116 also forces the other symmetrically opposing combustion chamber 116 to rotate in a clockwise direction. Since both combustion chambers 116 are oriented on the engine rotor 70 at approximately 180° apart with respect to each other, the rotary positive displacement engine 10 can be configured to fire twice per one revolution of the engine rotor 70. Therefore, there are two expansions and two compression cycles each revolution.

The rotary positive displacement engine 10 illustrated in the drawings has a cubic inch displacement of approximately 11.78 cubic inch displacement at 4 inches to center for a 23.56 cubic inch displacement per revolution. Advantageously, the power being generated from the rotary positive displacement engine 10 is transferred into rotational or circular motion, which can produce a high torque output.

Additionally, a plurality of combustion chambers 116 can be oriented on the engine rotor 70 to increase firing of the rotary positive displacement engine 10. Furthermore, a fuel injection system can be employed where fuel is injected into the combustion chamber 116.

It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims.





 
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