AU2008201574B2 - "Martin" cross-flow, 4 stroke side-valve engine - Google Patents

Description

PATENT SPECIFICATION Page 1 of 11 2 8 th Oct.. 2009 Complete Specification Entitled: Improvements in or related to Side-Valve Internal Combustion Engines. Applicant: Wesley David Martin. Actual Inventor: Wesley David Martin. Invention Title: "MARTIN" Cross-Flow, 4 Stroke Side-Valve Engine. Related Art: Diagrammatic views of only two examples of it's Invention principles in drawing Numbers: M1001, M1002 and M1003. Specification Application No: 2008201574. The Invention relates to improvements in devices for Internal Combustion Engines known as Side-Valve designs, which may be defined as 4 stroke engines having their Inlet and Exhaust Valves contained substantially within the Cylinder Block and not within the Cylinder Head as in Overhead-Valve or Overhead-Cam design Engines. There is a requirement for an improved efficient low cost simplified device. Aims of the Proposed Invention: The object of the present design is to produce an Engine which is substantially free from disadvantages inherent in existing Side-Valve designs, while providing performance similar to existing Overhead -Valve design Engines; but with the economical advantage of being easier to manufacture and maintain than Overhead Valve Engines due to its' designed simplicity; with reduced material mass and minimum number of components, which also results in a reduced dimensional profile. It would be ideal for industrial purposes, for example as motive power for Welders, Compressors, Generators, Mowers etc. but more importantly, very suited in multi cylinder configuration for combination with Electric Motors in Hybrid Vehicles because of its ability to safely operate continuously at maximum power output. Previously a number of designs have been produced using Side-Valves; however, these attempts have been unsatisfactory for the following reasons: (A )Those using Slide-Valves fail due to inadequate sealing against combustion pressures and suffer high energy losses through excessive friction in valve motion. (B) In the common type using Poppet Valves, their power/capacity ratio has been inferior due to their Inlet and Exhaust Valves being situated adjacent to each other, thereby forcing the Inlet Valve to absorb much of the intense heat from the Exhaust Valve. This then heats the incoming Fuel/Air mixture, reducing its' weight and volume and consequently its effectiveness in power generation.

Page 2 of 11 (C) A further disadvantage is the Inlet and Exhaust gases have conflicting, shared flow paths into and out of the Cylinder during the Valve 'overlap' ( that period from the commencement of opening of the Inlet Valve to the final closing of the Exhaust Valve), thereby seriously hindering the extraction of exhaust gas and its' potential positive effect on the induction of the Fuel/Air charge. (D) In most existing designs there is a lack of effective adjustment to Valve 'overlap' (E) In all existing designs, there is a lack of ability to achieve optimum compression ratios in relation to their Cylinder capacity. (F) In all existing designs, the approach of the Inlet and Exhaust Ports to their Valves is not straight and direct enough to the underside of the Valve heads, to facilitate ease of entry of the Fuel/Air mixture and efficient evacuation of the combustion products. The PROPOSED DESIGN overcomes these disadvantages as follows: (1) By positioning the Valves as far apart as is practical, thereby separating their flow paths and thus leaving the incoming Fuel/Air mixture in a unheated state, which gives it maximum weight by volume for optimum combustion pressures, plus the added benefit of the Inlet charge cooling the Exhaust Valve once the latter has closed. (2) The tremendous influence of the 'overlap' period in valve timing in Internal Combustion Engines cannot be overstressed, as it has a big effect on Gas throughput and consequently, Engine performance. In Engine design, the ability to adjust 'overlap' is significant, depending on the duty requirements and Fuel used. Super-charging and Turbo-charging and also low speed, high torque Work Engines require reduced 'overlap', while high speed, naturally aspirated Race Engines need serious increases. There are varying ranges between these extremes, which may occupy from approximately 50 to as much as 150 degrees of Crankshaft rotation. The PROPOSED DESIGN is very flexible in its ability to adjust 'overlap' by using separate Inlet and Exhaust Camshafts, so making Valve timing adaptable to any use. (3) The ability of an Engine to achieve sufficient compression of the Fuel/Air mixture, is of paramount importance for its' combustion to develop maximum power. The PROPOSED DESIGN of this Specification is very capable in this respect, having its two Valve to Cylinder passageways cross-sections, restricted to no more than the area equivalent to that required for the Valves' maximum Gas throughput. Their lengths are restricted by the rising domed shape of the Cylinder Head, imparting very generous entry areas to and exit from, the Cylinder. The domed-top Piston at its' top of travel, is closely matched to the shape of the Cylinder Head, creating 'squish' (acceleration of Fuel particle turbulence, to assist combustion and flame-front travel). These measures compact the combustion zone area, enabling suitable compression ratios to be achieved, (with the Valves and Ports being proportionally dimensioned to suit the Cylinder capacity).

Page 3 of 11 (4) The approach of the Inlet and Exhaust Ports to the Valves has a marked effect on the breathing efficiency of an Engine, (that is, its ability to completely fill the Cylinder with Fuel/Air mixture and exhaust all of the products of combustion). The PROPOSED DESIGN achieves the optimum, by the Ports being aligned to the Valves at approximately 45 degrees to the Cylinder centre line, giving the tuned intake column effect of the Fuel/Air mixture, an unimpeded direct flow to the Inlet Valve and similarly, easy exit for the products of combustion from the Exhaust Valve, this encouraged by the tuned exhaust system.

EDITORIAL NOTE APPLICATION NUMBER - 2008201574 It should be noted that the next page is numbered 8.

Page 8 of 11 Text for Related Art: Drawing No: M1001 Diagrammatic sectioned view. Not shown are: Crankcase; Oil Pump for lubrication; Fins or Jackets; Water Pump & Radiator etc. for cooling; Alternator & Spark Plug generation systems; Valve Spring covers; Fuel supply systems. Drawing No: M1002 Diagrammatic Plan of Cylinder Head (S) from combustion-chamber side, with Valve heads super-imposed to show location. Drawing No: M1003 Diagrammatic sectioned view of 'V' type Engine. The Inlet Ports are offset to introduce swirl in the combustion chamber and to allow room for separate Carburettors or Injectors. Cylinders are offset to allow both Conrods to pivot on a common Crank Pin. Cylinders and Heads are identical both sides for low cost manufacture. The Cam wheels are shown with (optional) Gear wheel drives from % time Pinion. Wesley D. Martin.

EDITORIAL NOTE APPLICATION NUMBER - 2008201574 It should be noted that the next page is numbered 4.