Nagata cycle rotary engine

Abstract

An internal combustion rotary engine consisting of casing (1) housing a rotor positioned slightly off-center of drive shaft (7) allowing A to displace the fuel/air mixture about the engine chamber. (2) Separating vanes (3) create separate chamber rooms (23) within the engine. Each separate chamber room (23) has its own capability to accomplish the four Otto cycles; intake, compression, combustion and exhaust in a 720-degree rotation of rotor (2). Each chamber room (23) also has its own method for combustion (8) as well as a set of intake valves (4) and exhaust valves (5) which draw in and expel the fuel/air mixture, respectively.

Description

DESCRIPTION

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] This invention relates to rotary engines.

[0003] 2. Description of the Prior Art

[0004] Since the invention of the rotary pump in 1588 by Ramelli, the concept of a properly functioning internal combustion rotary engine has been the “Holy Grail” of engine design. The only rotary engine to be mass-produced was the Wankel Rotary Engine. Even since its first mass production in the 1970's, the rotary engine has not enjoyed widespread production or success.

[0005] The main advantage of the rotary engine is, as its name implies, is rotational energy. Unlike the piston engine, a crankshaft and complex set of connecting rods are not needed to convert the up and down motion of a piston into rotational energy. This conserves energy, weight and manufacturing costs. Rotary engines also are known for their small size and high power to weight ratio.

[0006] Historically, rotary engines have been plagued by several problems. Leakage under pressure has been a problem with designs since Ramelli first invented the rotary pump. Later internal combustion designs all had overheating as a common design fault. In the 1970's, General Motors abandoned an ambitious rotary engine project due to strict new environmental regulations on vehicle emissions. Additionally, rotary engines have had gas mileage far below the industry standard and are notorious for needing major engine seal repairs.

[0007] Several improvements to the Wankel design have been implemented One such improvement is the apex seal which serves to reduce friction and fuel loss through leakage under pressure. Significant problems with the design still exist:

[0008] (a) There are engine vibration problems. The rotor chums in such a way as to cause it to vibrate. A balance weight must be added to decrease these vibrations. Even with this added weight there are still noticeable vibrations. The weight, of course, reduces overall efficiency.

[0009] (b) There are friction problems. Indeed all engines have friction problems. Rotary engine designs however, have considerable friction. In the Wankel design, the rotor must make three rotations inside the engine chamber for the drive shaft to rotate once. This 3:1 rotor to drive shaft causes friction and heat problems.

[0010] (c) There is difficulty manufacturing the engine. To date only the Mazda RX-7 uses a rotary engine design. Other companies have constructed test engines, but have not mass-produced them.

[0011] (d) There is a waste problem with the fuel/air mixture leaking under pressure. In most designs, including the Wankel, a small amount of the fuel/air mixture used for combustion is lost during the engine rotation process. This is a design flaw. In the Wankel design's case, as the rotor rotates, there is also a point where some of the fuel/air mixture escapes via the exhaust port.

[0012] (e) There is difficulty in repairing the engine. Problems inside the rotor chamber are very difficult to get to.

SUMMARY OF THE INVENTION

[0013] Accordingly, the previous disadvantages are remedied in our invention. Several objects and advantages of the invention are:

[0014] (a) to provide an engine that has a low level of vibration without the use of balancing weights thus allowing for a lighter engine;

[0015] (b) to provide an engine with greatly reduced engine friction;

[0016] (c) to provide an engine that is relatively easy to manufacture;

[0017] (d) to provide an engine that comprises few parts;

[0018] (e) to provide an engine that is smaller and more compact than existing ones;

[0019] (f) to provide an engine that conserves the fuel/air mixture.

[0020] Further objects and advantages are to provide an engine that because of the above listed objects and advantages will allow for superior gas mileage and performance.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 shows an end view of an engine design incorporating an eccentric shaft with 6 chambers. Swivel-type separating vanes are attached to the rotor. This design incorporates a timing belt/chain to activate the valves.

[0022] FIG. 2 shows an end view of a four-chamber design attached directly to the main drive shaft with spring-loaded vanes, one of the possible embodiments of the design. This design incorporates a stationary gear to manipulate the timing gears and activate the valves.

[0023] FIG. 3 shows a simplified side view of the same four-chamber style engine as in FIG. 2.

[0024] FIG. 4 shows an end view of a four-chamber engine design with an eccentric shaft.

[0025] FIG. 5 shows a side view of the same four-chamber style engine as in FIG. 4.

[0026] FIG. 6 shows an end view of a variation of the design with sparkplugs and ports contained within the rotor. The rotor in this case, is stationary and the outer casing rotates.

[0027] FIG. 7 shows a side view of FIG. 6.

[0028] FIG. 8 show an end view of an engine design with an eccentric shaft with 4 chambers. Swivel vanes are attached to the engine casing in this embodiment

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] The engine has a casing (1), which can be of various shapes. The rotor (2), which also can be of various shapes, is contained inside casing (1) and sits slightly off center of the drive shaft. Separating vanes (3), create separate chamber rooms within the engine. Each engine chamber contains the means to intake, compress, combust, and expel a fuel mixture. This process enables the engine to create rotational energy.

[0030] An embodiment of the present invention is illustrated in FIG. 1.

[0031] The engine has a casing (1), which in this case, is a hexagon shape. The rotor (2), which is also a hexagon shape, is contained inside casing (1). Swivel-type separating vanes (3), create separate chambers (23) within the engine. Fuel/air mixture enters each engine chamber through an in-take port (17), and intake valve (4). Valve spring (26) applies constant pressure on the valve to keep it closed. The motion of rotor (2) then compresses the fuel/air mixture and combusts it using sparkplug (8) Expended gas is then expelled through exhaust valve (5) and exhaust port (18). Combustion causes rotor (2) to move about the chamber.

[0032] This motion is converted to rotational energy with eccentric shaft (21) causing drive shaft (7) to rotate as the action is repeated in another chamber.

[0033] For every two rotations of rotor (2) camshaft (9) rotates once. As camshaft (9) rotates, it moves cam (6), which in turn acts to manipulate rocker arm (25). It is this manipulation of rocker arm (25) which causes intake valves (4) and exhaust valves (5) to open and close in each chamber room (23).

[0034] The opening and dosing of the aforementioned valves accomplish replenishment of the fuel air mixture inside each separate chamber room (23). In this embodiment, the fuel/air mixture travels through the intake port (17) and then travels through intake valve (4) and is sucked into the airtight chamber room (23) created by rotor (2) and separating vanes (3). After combustion, the spent gas leaves the chamber through exhaust valve (5) into the exhaust port (18). From there the spent gas exits the engine.

[0035] Instead of using gears in this process other possible variations of this design include; using belts, chains, or nuts to rotate camshaft (9). There are also various possibilities envisioned for the separating vane system. An embodiment of one such possibility can be seen in FIG. 1 where swivel vanes are attached to the rotor and slide freely in and out of vane hole (34) and vane slot (31). FIG. 8 depicts a design with swivel vanes attached to engine casing (1) and sliding freely in and out of vane hole (34) and vane slot (31) located in the rotor in this embodiment. Sliding vanes which move through the rotor are another possibility for the separating vane system.

[0036] Any number of separating vanes (3) can be incorporated to allow for any number of chamber rooms (23). Any number of intake valves (4) and exhaust valves (5) may also be used. To prevent friction a ball bearing (16) or similar system can easily be installed for the separating vanes (3) Furthermore, a crank and cam shaft can accomplish the same vane manipulation. It should also be noted that variations of the design with or without an eccentric shaft are possible as represented in FIG. 4 and FIG. 2 respectively.

[0037] Given that the area where the rotor comes closest to the chamber wall in FIG. 1 with the spark plug being located at 0 degrees., 180 degrees marks the area where the rotor is furthest from the chamber wall. From 0 degrees to 180 degrees the intake valve is open. As the intake valve opens, the fuel air mixture enters the engine chamber.

[0038] From 180 degree to 360 degrees the intake valve is dosed and no l air mixture enters the chamber. At this time the fuel air mixture in the chamber is compressed. As the rotor nears a complete 360-degree cycle and the fuel air mixture is at its highest point of compression the spark plugs ignite. This combustion causes a rapid increase in chamber pressure causing the rotor to rotate. This occurs from 360 degrees to 540 degrees. After this point the exhaust valve opens and the spent gas is purged through the rotor and out the timing side exhaust hole. This purging process occurs from 540 degrees to 720 degrees.

[0039] Explanation of Four Engine Cycles:

[0040] Cycle one-intake process 0-180 degrees

[0041] Cycle two-compression press 180-360 degrees=one rotation

[0042] Cycle three-combustion process 360-540 degrees

[0043] Cycle four-purge process 540-720 degrees=two rotations

[0044] This invention achieves the same results in two rotations as does a conventional for-stroke internal combustion engine.

[0045] Accordingly, the reader will see that the invention described here has numerous advantages over existing designs. This invention is smaller and lighter than existing designs. Additionally, the advantages described will allow for superior gas mileage and performance in that this invention; solves vibration problems; eliminates the need for balance weights; has greatly reduced engine friction compared to the piston engine and existing rotor engine models; is easy to manufacture; solves existing rotary engine fuel/air mixture waste problems and is easy to maintain and repair because of its simplicity.

[0046] Although the description above contains many specificities, these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the presently preferred embodiments of the engine. For example the engine can have any number of separating vanes or a slightly different shaped engine casing, etc.

[0047] Thus the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.

[0048] Parts List

[0049] 1) Casing 17) Intake port

[0050] 2) Rotor 18) Exhaust port

[0051] 3) Separating vanes 21) Eccentric shaft

[0052] 4) Intake valve 22) Side seal

[0053] 5) Exhaust valve 23) Chamber room

[0054] 6) Cam 24) Vane spring

[0055] 7) Drive shaft 25) Rocker arm

[0056] 8) Spark plug or injector 26) Valve spring

[0057] 9) Cam shaft 31) Separating vane slot

[0058] 10) Timing gear 33) Timing belt

[0059] 11) Stationary gear 34) Separating vane hole

[0060] 12) Side casing 35) Separating vane swivel

[0061] 16) Shaft support bearings

Claims

1. A rotary engine, comprising: A housing defining a chamber having an interior surface and ends and a central chamber axis passing therethrough; a drive shaft disposed within the chamber and having a longitudinal drive shaft axis parallel to the chamber axis; a rotor situated slightly off center of the drive shaft; three or more separating vanes dividing the engine chamber into separate chamber rooms; said chamber rooms containing intake and exhaust ports as well as a means to combust the fuel air mixture; said chamber also containing intake valves in fluid communication with an intake port to permit a fuel/air mixture to enter the chamber, said intake valves serving to regulate the amount of fuel/air mixture which may enter the chamber; a combustion mechanism existing in each individual chamber; said chamber also containing exhaust valves in fluid communication with an exhaust port to permit spent fuel/air mixture to exit the chamber; said exhaust valves serving to regulate the amount of fuel/air mixture which may exit the chamber, said intake and exhaust valves are connected to the drive shaft via a timing system for the purpose of opening and closing the valves.

2) Whereas the rotor is situated slightly off center of the drive shaft (as in claim 1), an eccentric shaft exists to transfer the engine motion into rotational motion.

3) Separating vanes pivotably attached to the rotor or the engine-casing wall, said vanes are able to remain in contact with the rotor or the engine-casing by having maneuverability within a vane hole and vane slot to house said vanes at full displacement.