GB2464267A - Rotary inlet and exhaust valves eg for i.c. engines - Google Patents

Abstract

A rotary valve 1 controls flow 4, 7 into and out of a chamber 5, or adjacent chambers 5. The rotary valve may be used as its own bearing 1,12 to eliminate the need for additional bearings eg by providing a bearing shell (12, fig. 11) around the valve. A space-saving combined rotary valve allows the use of Siamese inlet 13 and exhaust 14 ports. The rotary valve may be used, in any multiple, with any fuel type of four-stroke engine and with any drive mechanism. For example, fig.7, two space-saving combined rotary valves 1 may be mounted on a common shaft 8 in an in-line four cylinder engine 10 or two such shafts may be used in a flat six-cylinder engine (11, fig.8). In other arrangements for an inline four-cylinder engine, two parallel valve shafts are used having a total of four (fig. 9) or three (fig. 10) rotary valves. The rotary valve may be used to produce new engine types or replacement cylinder heads for existing engines. The rotary valve may be used in other applications including industrial or commercial systems or devices.

Description

Space Saving Combined Rotary Valve

Description

This invention relates to a method of controlling flow into and out of a chamber.

The initial application for this device is to control the inlet and exhaust gases of four stroke engines.

Other applications for this device may follow including industrial applications (e.g. pumps or flow control).

A four-stroke engine consists of four stages of operation which are made up of an induction stroke, a compression stroke, a power stroke and an exhaust stroke. The induction and exhaust strokes are the stages of the cycle that the inlet and exhaust gases are moved into and out of the combustion chamber.

Most current four stroke engines use a combination of camshafts, springs and "mushroom headed" valves to control the inlet and exhaust gases. This arrangement has been used successfully for many years but has several drawbacks including: * Complexity Many moving parts are required which entail detailed construction and maintenance procedures.

* Mass The space required to house the parts causes the cylinder head to be bulky and heavy.

* Flow limitation The head and stem of the valve restricts gas flow into and out of the combustion chamber. This is more noticeable at higher engine speeds.

* Damage As the valve heads intrude into the combustion chamber any failure of the valve timing system may cause catastrophic damage to the engine concerned.

* Speed limitation Due to the inertia problems of valves the maximum speed of the engine is limited by its valve gear. This often manifests itself as "valve bounce".

A Combined Inlet and Exhaust Rotary Valve (CIERV) reduces the complexity and mass of the cylinder head whilst improving the gas flow and eliminating the possibility of "valve bounce". The CIERV also eliminates the possibility of damage, from piston-to-valve contact, due to valve timing system failure.

The CIERV may be used with any type of fuel (e.g. Petrol, Diesel, LPG etc).

A CIERV cylinder head may be produced to replace an existing conventional overhead cam (OHC) cylinder head using the original camshaft drive system.

The CIERV concept has existed, in various forms, from the early part of the 20th century and is not able to be patented.

The Space Saving Combined Rotary Valve (SSCRV) combines the rotary valves for a pair of combustion chambers together and may also be used as the bearing that supports the combined valves and any associated shafts.

The SSCRV will be described with reference to the following accompanying drawings: Figure 1 shows a simplified view of the SSCRV Figure 2 shows a simplified "cut away" view of the SSCRV Figure 3 shows a simplified "cut away" view of the SSCRV during the induction stroke Figure 4 shows a simplified "cut away" view of the SSCRV during the exhaust stroke Figure 5 shows a simplified view of a shaft driven SSCRV Figure 6 shows a simplified view of a gear driven SSCRV Figure 7 shows a simplified view of the SSCRV used on an "inline' four-cylinder engine Figure 8 shows a simplified view of the SSCRV used on a "flat" six-cylinder engine Figure 9 shows a simplified view of "dual" SSCRVs used on an "inline" four-cylinder engine Figure 10 shows a simplified view of "staggered" SSCRVs used on an "inline" four-cylinder engine Figure 11 shows a simplified view of an SSCRV used as its own bearing Figure 12 shows a simplified view of an SSCRV used in a "Siamese" port cylinder head The SSCRV is a cylindrical (or spherical or any complex combination of the two) device that has flow passageways through it that allows gas flow into and out of the combustion chamber.

Figure 1 shows a single SSCRV (1) that rotates about the axis (2) with the passageway (3) opening visible.

Figure 2 shows "side on" a cut away view of a single SSCRV (1) that rotates about the axis (2) with the passageway (3) visible. Note that the passageway does not need to be "straight", as shown in figure 2, but may be curved or two "straight" passageways connected.

The SSCRV rotates, controlled by (although not necessarily driven by) the engines crank position, to allow air/fuel mixture into the combustion chamber during the induction stroke and burnt exhaust gases out of the chamber during the exhaust stroke.

Figure 3 shows the SSCRV (1), during the induction stroke, allowing the fuel/air mixture (4) into the combustion chamber (5) while the piston (6) travels downward.

Figure 4 shows the SSCRV (1), during the exhaust stroke, allowing the exhaust gases (7) Out of the combustion chamber (5) while the piston (6) travels upward.

The SSCRV may be mounted on a shaft or driven by other means (eg gears or chain).

Figure 5 shows a shaft (8) driven SSCRV (1).

Figure 6 shows a gear driven SSCRV (1) where the gear (9) is attached to the SSCRV.

The SSCRV may be used singly (ie one per cylinder) or in multiples (eg two per cylinder) on any variation of four stroke engine (eg "inline" four cylinder, "flat" six cylinder, "vee" eight cylinder etc).

Figure 7 shows a simplified view of 2 SSCRVs (1) used, on a common shaft (8), with an "inline" four-cylinder engine (10).

Figure 8 shows a simplified view of 4 (i.e. two SSCRV per shaft), SSCRVs (1) used, on two shafts (8), with a "flat" (or horizontally opposed) six-cylinder engine (11).

The SSCRV may be used one per cylinder (or pair of cylinders) or used in other combinations and arrangements.

Figure 9 shows a simplified view of 4 SSCRVs (1) used, on 2 shafts (8), with an "inline" four-cylinder engine (10).

Figure 10 shows a simplified view of 3 SSCRVs (1) used, on 2 shafts (8), with an "inline" four-cylinder engine (10).

The SSCRV may be used as a load-bearing surface to eliminate the need for additional bearings on the common shafts or individual SSCRVs.

Figure 11 shows a simplified view of a SSCRV (1) used, on a shaft (8), with bearing shells (12) around it. The passageways (3) are shown coming through the bearing shells in this instance but "partial" bearing shells (eg covering only 270 degrees of the SSCRV) may be used.

The SSCRV may be used as an independent intake/exhaust valve per cylinder or used to produce "Siamese" ports where separate cylinders use the same inlet and exhaust ports on the cylinder head.

Using this "Siamese" arrangement would reduce the number of inlet and exhaust ports a cylinder head would need and would allow for a more compact and lighter design.

Figure 12 shows a "top down" cut away view of a SSCRV (1)that rotates about the axis (2) with the passageways (3) shown in a parallel twin cylinder engine. The single inlet port (13) and exhaust port (14) are shown between the chambers (5). Notes

1. The SSCRV is described above, as it would be used in a four-stroke internal combustion engine. All of the design features mentioned may be used in other applications to control flow into a chamber or adjacent chambers (e.g. pumps etc).

2. Most of the figures show the SSCRV with vertical and horizontal faces but angled faces or curved faces may be used if necessary (see figure 1). An angled face SSCRV would maintain a more even combustion chamber wall thickness in the majority of four stroke engines.

Claims (5)

1. Claims 1. A rotary valve that controls flow into and out of a chamber.
2. 2. A rotary valve that may be used to control flow into and out of a pair of adjacent chambers.
3. 3. A rotary valve that allows "Siamese" inlet and exhaust ports between a pair of adjacent chambers.
4. 4. A rotary valve that may be used as its own bearing.
5. 5. A rotary valve that may be used, in conjunction with other parts, to upgrade an existing valve system (eg replacement cylinder head).