HK1128318B - Improved valve seal assembly for rotary valve engine - Google Patents

Description

Improved valve seal assembly for rotary valve engine

Field of the invention

The present invention relates to an internal combustion engine of the piston-cylinder type having a spherical rotary valve assembly for introducing a fuel/air mixture into the cylinder and evacuating exhaust gases, in particular to a float valve seal for such a rotary valve assembly and means for regulating pressure in a valve, especially in valves for long-stroke, high-compression engines such as diesel engines.

Background

The present inventors are concerned more here with internal combustion engines of the piston-cylinder type, and in particular how to replace the poppet valve system, comprising the poppet valve, the spring, the seat and the associated camshaft, with a spherical rotary valve assembly in order to introduce the fuel-air mixture into the cylinder and to evacuate the exhaust gases. The applicant is also the signed inventor of the following patents: U.S. patent No. 4,989,576 "internal combustion engine"; us patent No. 4,944,261 "spherical rotary valve assembly for internal combustion engines"; us patent No. 4,953,527 "spherical rotary valve assembly for internal combustion engines"; U.S. patent No. 4,976,232 "valve seals for rotary valve engines"; us patent No. 4,989,558 "spherical rotary valve assembly for internal combustion engines"; U.S. patent No. 5,109,814 "spherical rotary valve"; U.S. patent No. 5,361,739, "spherical rotary valve assembly" for use in rotary valve internal combustion engines; U.S. patent No. 6,308,676B 1, "cooling system for rotary valve engine", and still pending U.S. patent application No. 10/280,293. The foregoing U.S. patents are incorporated herein by reference to the extent and detail listed therein.

The valve seal described in applicant's prior patent is a floating valve seal within a valve seat. The valve seals are located within the lower half of the split cylinder head assembly adjacent to the cylinder intake and exhaust ports. A biasing means is located within the valve seat and the valve seal is located above the biasing means. The upper surface of the valve seal is arcuate in shape to conform to the perimeter of a spherical rotary intake valve or a spherical rotary exhaust valve assembly. The lower body of the valve seal seated in the valve seat has one or more sealing rings therearound in annular sealing contact with the outer wall of the valve seat. In this design the valve seal floats within the valve seat with a slight gap between the inner wall of the valve seat and the valve seal so that compressed gas can enter the valve seat through the gap and pressurize the area between the valve seal and the valve seat during the compression stroke, which in turn causes the valve seal to make airtight sealing contact with the spherical rotary intake and exhaust valves.

In a short stroke engine, the rotary valve assembly operates without modification due to the shorter stroke of the piston and the resulting pressure generated. However, in long stroke engines such as diesel engines, the compression ratio is much greater than in conventional internal combustion engines, and this compression actually causes detonation of the fuel/air mixture at significantly higher pressures, which causes excessive pressure on the floating valve seal and contact with the spherical rotary intake or exhaust valve, and therefore the valve seal of the diesel rotary valve assembly needs to be structurally modified.

The present invention, the subject of this application, relates to such floating valve seals and the means for regulating pressure therein.

Summary of The Invention

It is an object of the present invention to provide a new and improved valve seal for a rotary valve engine.

It is another object of the present invention to provide a new and improved valve seal for a rotary valve engine wherein the ceramic insert of the valve seal is positioned within a locking angle to increase service life.

It is a further object of the present invention to provide a new and improved valve seal for a rotary valve engine wherein a hermetic seal is maintained by the pressure generated within the cylinder and combustion chamber.

It is a further object of the present invention to provide a novel and improved valve seal for a spherical rotary valve assembly which does not require external lubrication.

It is a further object of the present invention to provide a new and improved valve, valve seal and cylinder head/combustion chamber arrangement for a rotary valve engine.

It is a further object of the present invention to provide a new and improved float valve seal arrangement for a rotary valve engine assembly which regulates pressure within the valve seal.

The present invention provides a valve seal for a rotary valve assembly of a piston and cylinder type internal combustion engine, such as a diesel engine, wherein the cylinder head/combustion chamber is designed for high compression and long stroke, and the rotary valve and valve seal are positioned in relation to allow the cylinder to be charged with a fuel/air mixture and to exhaust gases, and to regulate the pressure within the valve seal and valve seat, thereby regulating the pressure between the valve seal and rotary valve.

Brief description of the drawingsMing dynasty

These and other advantages and improvements of the present invention will become apparent, particularly upon reference to the following drawings wherein:

FIG. 1 is an end view cross-section illustration of a spherical rotary valve assembly cylinder head showing the relationship of the spherical rotary valve to the cylinder, piston and valve seal;

FIG. 2 is a top view of the improved valve seal of the present invention;

FIG. 3 is a side view of the improved valve seal and valve seat of the present invention taken along plane 3-3 of FIG. 2; and

FIG. 4 is a top view of the pressure adjustment ring of the improved valve seal of the present invention.

Detailed description of the invention

Referring to FIG. 1, there is shown an end cross-sectional view of one embodiment of a spherical rotary valve assembly of the applicant's earlier patent detailing the relationship of a rotary intake valve 10 enclosed within a split cylinder head assembly upper half 12 and lower half 14 with its surroundings. The split cylinder head assembly is secured to an engine block having a cylinder 16 with a piston 18 reciprocally movable within the cylinder 16.

The split cylinder head assembly has an upper half 12 and a lower half 14 defining a drum-like receiving cavity 20 within which the rotary intake valve 10 is seated on a shaft 22 extending through a central bore 24 of the rotary intake valve 10. As detailed in earlier patents of the applicant previously disclosed, the rotary intake valve 10 communicates the fuel and air intake port 26 with the cylinder 16 by means of a bore 30 disposed in the spherical surface 21 of the rotary valve 10, in turn aligned with an intake port 32 to the cylinder 16.

The intake valve 10, rotating on the shaft 22 inside the drum-like housing cavity 20, is in contact with a valve seal 35 placed in an annular groove 38 around the inlet port 32 to the cylinder 16. The valve seal 35 has the following functions: a seal is provided during the intake stroke to ensure that the fuel/air mixture is communicated from the rotary intake valve 10 into the cylinder 16. A seal is provided in conjunction with the rotary intake valve 10 during the compression stroke to ensure that ignition of the fuel/air mixture occurs within the cylinder 16 without migration into the drum-like receiving cavity 20. In addition, a seal is provided with the rotary intake valve 10 during the exhaust stroke to ensure exhaust gas is expelled through the rotary exhaust valve.

The description herein of the valve seal is made with respect to the rotary intake valve shown in fig. 1. For a rotary exhaust valve in a spherical rotary valve assembly, the valve seal is of the same design and serves the same purpose and function as disclosed in the applicant's previously identified patents. It is also understood that each cylinder has at least one rotary intake valve and at least one rotary exhaust valve, and that each valve has a valve seal.

Referring now to fig. 2 and 3, a top view and a cut-away view, respectively, of an improved valve seal is shown showing the valve body 37 and ceramic carbon insert lube ring 52, as will be described in greater detail below. When the valve seal 36 is seated within the annular groove or seat 38, the central bore 40 of the valve seal 36 may be aligned with the inlet port 32. The upper annular surface 42 of the valve body 37 is curved toward the center of the inward hole 40 with a curvature corresponding to the curvature 23 of the spherical surface of the rotary intake valve 10. The upper surface 42 of the valve body 37 is formed with an annular groove 44 formed by an inner sidewall 46 and an outer sidewall 48. The inner sidewall 46 forms an angle of 90 degrees and the outer sidewall 48 forms an angle of less than 90 degrees. The annular groove 44 is adapted to receive a ceramic carbon insert lube ring 52. The ceramic carbon insert lube ring 52 is positioned within the annular groove 44 such that its upper surface 54 corresponds to the curvature of the upper surface 42 of the valve body 37. The carbon insert lube ring is fitted to the valve body 37 by heating the valve body 37 to slightly expand it and then inserting the lube ring 52 into the heated annular groove 44. The valve body 37 is then cooled. Since the outer side wall 48 of the annular groove is slightly offset 90 degrees in the direction of the inner side wall 46, the lube ring 52 is locked in place by this "locking angle" and can be assured to stay in this position, despite how hot the valve seal 36 can become during combustion in an internal combustion engine. This is particularly important when the internal combustion engine to which the valve seal is attached is powered by natural gas or diesel, because it can generate much higher temperatures and pressures than conventional gasoline fuels.

The outer side wall 54 of the valve seal 36 is stepped and formed with a spaced annular rib 56 to receive and seat at least one sealing ring 58 that functions much like a piston ring to establish a seal between the side wall 54 of the valve seal 36 and the periphery of the annular groove or seat 38 around the inlet port 32. Only one rib 56 and one sealing ring 58 are shown in this embodiment. However, if the depth of the sidewall 54 is increased, the number of seal rings may also be increased.

Contact between the valve body and the rotary intake valve 10 is maintained by an annular disc spring 60 seated in a valve seat annular receiving groove. In doing so, the pressure to be maintained upward on the valve body is between 1 and 4 ounces.

In addition, a pressure adjustment ring 64 is disposed on the inner wall 62 of the valve seat 38. In applicants' previous embodiment, increased gas pressure in the cylinder during compression and power strokes has been used to increase the seal between the valve body and the rotary valve periphery by using annular passage 66. It has been found that the increased compression in the valve seat during the compression and power strokes of a short stroke engine does not require regulation. However, in long stroke and high compression engines such as diesel engines, the pressure within the valve seat that increases the contact of the valve body with the peripheral surface of the rotary valve must be adjusted or the seal will have a braking effect on the rotation of the rotary valve. Accordingly, the pressure adjustment ring 64 is positioned within the annular groove 65 in the inner wall of the valve seat 38 on the path of the compressed gas from the cylinder during the compression and power strokes such that the pressure adjustment ring 64 does not contact the inner annular surface of the valve body 36. A plurality of orifices 66 are formed in the outer circumference of the pressure adjustment ring 64 and pressurized gas from the cylinder may flow through the orifices 66 into the valve seat 38 below the valve body 36, thereby reducing the pressure build-up of the peripheral surface of the rotary valve on the valve body. Fig. 4 is a top view of the pressure adjustment ring of the present invention. The aperture 66 is in the form of a semi-circular aperture formed in the outer periphery of the sealing ring 64.

Heretofore, applicants' "floating" valve seal body has been to allow the compressed combustion gases from both the compression and power strokes to flow into the valve seat through the annular gap 66 between the inner peripheral wall of the valve body and the inner peripheral wall of the valve seat 38. The pressure adjustment ring 64 serves to restrict the passage of the compressed gas through the path, which it blocks, leaving only a plurality of orifices 66 for introducing the compressed gas into the valve seat 38 below the valve body 36. The number of orifices 66 may vary depending on the stroke and compression of the engine as measured by suitable measurement techniques.

The applicant/inventor has appreciated from the valve seal and valve seat of the previous prototype that the valve seat should be a friction fit in an annular groove in the lower half of the split cylinder head assembly. The valve and valve seat of the present invention may also be friction fit within such an annular groove. However, since the valve and valve seat of the present invention are directed to engines having much higher compression and long strokes than those found in conventional automotive internal combustion engines, the valve seat may be externally threaded onto the outer peripheral surface 70, or may be threaded into an annular groove in the lower half of the cylinder head assembly.

Although the present invention has been described in connection with exemplary embodiments thereof, it should be understood that many modifications and variations may be made by those skilled in the art without departing from the spirit and scope of the invention, and it is therefore apparent that the invention is limited only by the appended claims and their equivalents.

Claims (5)

1. A valve seal for a rotary valve assembly of an internal combustion engine of the piston-cylinder type having high compression and long stroke, the rotary valve assembly being disposed within a two-piece cylinder head defining a plurality of drum-like receiving cavities for receiving rotary intake and rotary exhaust valves having spherical portions defined by two parallel planes of the ball, said planes being symmetrically disposed about the center of said ball defining a spherical periphery and planar end walls, said rotary intake and rotary exhaust valves being mounted on axle means within said drum-like receiving cavities in airtight sealing contact with an intake port and an exhaust port respectively, said rotary intake and rotary exhaust valves having passages therethrough for the introduction or cessation of fuel-air mixtures into the engine and the evacuation of exhaust gases from the engine respectively, said rotary intake valve and said rotary exhaust valve being in airtight sealing contact with said intake port and said exhaust port, respectively, by a valve seal and a valve seat having:

a valve body member of substantially circular cross-section, said valve body member having an arcuate annular upper surface conforming to the spherical periphery of said intake valve or said exhaust valve, a through bore defined by an inner circular sidewall conforming to said bore of said intake port or said exhaust port, an annular receiving groove formed in said arcuate upper surface around said bore for receiving a lubricating insert ring, said lubricating insert ring having a chordal upper surface complementary to said arcuate upper surface of said valve body member;

said valve body member further having a peripheral sidewall with a plurality of mounting ribs formed thereon for positioning a plurality of sealing rings about said peripheral sidewall of said valve body member to sealingly engage said valve body member with said outer wall of said valve seat;

said valve seat having an outer wall and an inner wall defining an annular groove for receiving said valve body, said inner wall of said valve seat having an annular groove formed in an inner surface thereof for receiving a pressure adjustment ring in contact with said valve body, said pressure adjustment ring having a plurality of passages therethrough for the passage of compressed gas during the compression and power strokes of said engine to apply upward sealing pressure to said valve body.

2. A valve seal for a rotary valve assembly according to claim 1 wherein said pressure adjustment ring passages are semi-circular and are formed on the outer peripheral surface of said pressure adjustment ring.

3. A valve seal for a rotary valve assembly according to claim 1 wherein the number of said passages in said pressure regulator ring determines the upward pressure required to be applied to said valve body.

4. A valve seal for a rotary valve assembly according to claim 1 wherein said valve seat is frictionally received in a groove in said two-piece cylinder head.

5. A valve seal for a rotary valve assembly according to claim 1 wherein said valve seat is threadably secured in an annular groove in said two-piece cylinder head.