WO2013048262A1

WO2013048262A1 - An internal combustion engine

Info

Publication number: WO2013048262A1
Application number: PCT/NZ2012/000174
Authority: WO
Inventors: Roger John Smith
Original assignee: Hieff Engine Company Limited
Priority date: 2011-09-30
Filing date: 2012-09-28
Publication date: 2013-04-04
Also published as: NZ595493A; AU2012268837A1

Abstract

An internal combustion engine which produces improved torque over known engines. The engine comprises a piston configured to move within a piston cylinder throughout a stroke cycle; a rotatable crankshaft comprising a crankshaft cam surface; a piston connecting rod pivotally connected to the piston; a crankshaft timing rod pivotally connected to the piston connecting rod at a conrod joint and to the crankshaft; a rocker arm configured to contact the crankshaft cam surface during its rotation cycle and to the conrod joint to move same to form a working crank angle between the piston connecting rod and the crankshaft timing rod when the piston is at its top dead centre (TDC) position and at its position of maximum displacement within the piston cylinder to slow the travel of the piston through the TDC and maximum displacement positions during the piston stroke for a predetermined angle of rotation of the crankshaft.

Description

AN INTERNAL COMBUSTION ENGINE

STATEMENT OF CORRESPONDING APPLICATIONS

The present application is based on the provisional specification filed in relation to New Zealand Patent Application No. 595493.

TECHNICAL FIELD

The invention relates to improvements in an internal combustion engine. In particular, the present invention relates to an improvement in the connecting rod and crankshaft mechanism of an internal combustion engine which may allow for greater efficiency and increased torque.

BACKGROUND ART

A conventional internal combustion engine of the type used to power passenger vehicles such as cars utilises an array of pistons each enclosed in a piston cylinder. Each piston is connected to a crankshaft via a connecting rod which converts the linear motion of the piston to rotary motion on the crankshaft.

It is well recognised in the engineering world that the present design of the internal combustion engine is highly inefficient in that a vast amount of the energy expended from the time of combustion to the completion of the expansion stroke, is utilised for displacing the piston and crankshaft from their top dead centre position (TDC) with little torque being developed by the crankshaft until the rotation of the crankshaft produces a workable lever of the connecting rod. By the time a workable lever is produced on the crankshaft the loss of workable pressure is already evident.

Conventional internal combustion engines are built with the axis of the piston cylinder and the axis of rotation of the crankshaft sharing a common plane. Many attempts have been made over the years to increase the efficiency of the conventional engine design. One such attempt involves laterally offsetting the axis of rotation of the crankshaft from the axis of the piston cylinder. If the crankshaft is configured appropriately, the engine may benefit through increased torque placed on the crankshaft as well as a reduction in frictional forces between the piston and the piston cylinder.

However, when the crankshaft is offset, one problem that results is that a conventional connecting rod will hit either the piston skirt or the bottom edge of the piston cylinder due to the increased angle between the connecting rod and the axis of the piston cylinder. It should also be noted that by increasing the length of the connecting rod the return stroke angle can be reduced, thereby decreasing the frictional forces between the pistons and the piston cylinders.

Some engine designs have increased the length of the connecting rod to try and improve the dwell of the piston at top dead centre thereby increasing combustion pressure generated in the combustion chamber at top dead centre, but engine designers have found this does little to increases the torque and horsepower output of the engine.

There have been a number of inventions where the connecting rod is adjustable in length by utilising mechanical and/or electronic devices. This is achieved by configuring the connecting rod with a flexible join in its length which allows the connecting rod to be moved at the join thereby altering the length between the crankshaft journal and the wrist pin of the piston.

One such example of this configuration is disclosed in US Patent No. 7,021 ,254. Here the engine configuration demonstrates that the connecting rod join when displaced sideways will alter the length of the two connecting points between the crankshaft journal and the piston wrist pin.

The purpose of this configuration is to move the piston towards or away from the connecting rod connecting point while the engine is running to alter the length of the connecting rod to suit different cylinder pressure loads. As the cylinder pressure drops due to a light throttle position, the piston will move towards the connecting rod causing it to straighten and become longer and thereby raising the compression ratio of the engine.

However, a disadvantage of this mechanism is that it requires constant adjustment during the running of the engine. Also, it does not address the problem of providing an efficient working angle or lever while there is high pressure in the cylinder and hence increased torque output.

Later developments of engines utilizing a connecting rod with a flexible join along its length have at least one electronic device attached to the flexible joint by means of a lever or other attachment mechanism. The electronic device(s) can be programmed to raise or lower the piston via the connecting rod as the crankshaft reaches its TDC position. The disadvantage of this type of arrangement is that reliability can be impaired being reliant on electric power.

US 7,174,863 discloses a rocking mechanism that is attached to the connecting rod. The purpose of this mechanism is to alter the capacity of the engine while it is running. However, a disadvantage of this mechanism is that it requires constant adjustment during the running of the engine. Again, there is no arrangement that will allow an efficient working angle lever while there is high cylinder pressure and hence increased torque output.

WO 03/008785A1 discloses a split cycle engine developed by the Scuderi Group which has two paired cylinders, one for compression of the air/fuel mixture and the other for the combustion power stroke. The split cycle design has been known since the early 1900s. However, the 'Scuderi Engine' is configured to fire after top dead centre (TDC), a feature which distinguishes it from previous split cycle engines.

In particular, the compression cylinder receives the air/fuel mixture on the downward stroke and compresses this mixture on the upward/compression stroke. The compressed mixture is released into a crossover chamber between the two cylinders as the piston reaches TDC position. The valve to access the cross over chamber is opened prior to the piston reaching its TDC position and closes prior to TDC.

The combustion cylinder forces the exhaust gases out of the exhaust valve which opens as the piston rises to its TDC position. This valve closes at TDC with the inlet valve opening as the piston commences on the downward power stroke. The combustion starts between 11 and 15° after TDC and continues to 23° after TDC.

However, the Scuderi engine does not solve the problem of having a working lever when the piston is at the top of the cylinder as the angle on the crank is zero at TDC and there is no working lever. The Scuderi engine configuration attempts to maintain pressure in the combustion cylinder by storing the air/fuel mixture in the cross over chamber and releasing this into the combustion chamber after TDC.

A disadvantage of this engine is that during the combustion stroke, pressure is falling in the combustion chamber and cylinder as the piston is travelling down the cylinder during the power stroke while it is creating a working angle on the crank. The result of this configuration is that this arrangement is no different from a conventional engine where pressure falls as the piston goes from TDC with no angle on the crankshaft to a lower cylinder pressure as the piston travels down the cylinder in order to create a working angle on the crank.

A further distinction of the Scuderi engine over conventional internal combustion engines is that it uses one cylinder to compress the air/fuel mixture and stores it in a crossover chamber.

However, this engine configuration does not create extra pressure as the volume of the air/fuel mixture is limited to the volume of the cylinder. This is the same as the combustion cylinder and hence no different to the limitations on cylinder volume for that of a conventional Otto Cycle engine. The compressed air/fuel mixture of the Scuderi engine is also released into the combustion chamber as the piston is displacing volume as it travels down the cylinder.

A further feature of the Scuderi engine is the firing of the flame after TDC which results in the air/fuel mixture expanding as the flame burns. Nevertheless, the pressure is being expended as the piston travels down the cylinder

The applicant has observed that it would be advantageous to have an improved internal combustion engine which addresses the foregoing problems.

It is an object of the present invention to address the foregoing problems or at least to provide the public with a useful choice.

All references, including any patents or patent applications cited in this specification are hereby incorporated by reference. No admission is made that any reference constitutes prior art. The discussion of the references states what their authors assert, and the applicants reserve the right to challenge the accuracy and pertinence of the cited documents. It will be clearly understood that, although a number of prior art publications are referred to herein, this reference does not constitute an admission that any of these documents form part of the common general knowledge in the art, in New Zealand or in any other country.

It is acknowledged that the term 'comprise' may, under varying jurisdictions, be attributed with either an exclusive or an inclusive meaning. For the purpose of this specification, and unless otherwise noted, the term 'comprise' shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non- specified components or elements. This rationale will also be used when the term 'comprised' or 'comprising' is used in relation to one or more steps in a method or process.

Further aspects and advantages of the present invention will become apparent from the ensuing description which is given by way of example only.

DISCLOSURE OF THE INVENTION

According to one aspect of the present invention there is provided an internal combustion engine comprising:

• a piston configured to move within a piston cylinder throughout a stroke cycle;

• a rotatable crankshaft comprising a crankshaft cam surface; and

• a connecting rod assembly comprising: o a piston connecting rod pivotally connected at one end to the piston; and

o a crankshaft timing rod pivotally connected at one end to the piston connecting rod at a conrod joint and at another end to the crankshaft

• a rocker arm configured to contact the profile of the crankshaft cam surface during its rotation cycle at one end and connected to the conrod joint at another end wherein the rocker arm is configured to move the conrod joint as the rocker arm moves on the crankshaft cam surface to form a working crank angle between the piston connecting rod and the crankshaft timing rod when the piston is at its top dead centre (TDC) position and at its position of maximum displacement within the piston cylinder during a piston stroke cycle, to slow the travel of the piston through the TDC position and the position of maximum

displacement during the piston stroke for a predetermined angle of rotation of the crankshaft.

In this way the crankshaft and connecting rod assembly are configured to allow the maximum pressure developed in the combustion chamber to be transferred to increased output torque on the piston at a time when the piston is close to top dead centre (TDC).

Preferably, the rocker arm is connected to the conrod joint via a rocker arm connecting rod connected to the conrod joint at one end and the rocker arm at another end.

More preferably, the rocker arm is connected to the conrod joint at an angle of less than 90 degrees.

Preferably, the predetermined angle and rotation of the crankshaft may be between 0.1° to 40° where the piston is held at its TDC position.

More preferably, the predetermined angle and rotation of the crankshaft may be 10-15° where the piston is held at its TDC position.

More preferably still, the predetermined angle and rotation of the crankshaft may be 12° where the piston is held at its TDC position.

As will be appreciated by those skilled in the art, the topmost position towards the cover end side of the cylinder in an internal combustion engine is known as the top dead centre (TDC) position. The rotation of the crankshaft in an internal combustion engine causes the piston in the cylinder to rise and fall. It is well known by those skilled in the art that when the crankshaft rotates at least one degree from TDC position there occurs in the cylinder what is known as displacement. The displacement of the cylinder may be a small amount, but nevertheless there is displacement or an increase in volume above the top of the piston and is a characteristic of internal combustion engines. In this way there is a period of dwell where the piston is held at the top dead centre position during a combustion stroke of the piston within the piston cylinder such that there is no displacement of the piston until an efficient working angle is achieved by the crankshaft and connecting rod assemblies. Only after increasing the working angle on the crankshaft and connecting rod assemblies to a more efficient angle does displacement take place. This piston dwell at the top of the cylinder allows the crankshaft to continue rotation until an efficient working lever is established such that an efficient lever can be exerted on the crankshaft without producing more stroke.

The typical range for maximum pressure developed in the combustion chamber may be between 600-1300 psi. However, it should be appreciated by those skilled in the art that this range should not be seen as limiting in the embodiments envisaged for this invention. For example, peak pressure is not constant and may vary from stroke to stroke in a single cylinder even at a constant throttle position as the intake manifold has pressure pulses which can affect the reloading of the incoming charge for each cycle.

The above configuration contrasts with that of a crankshaft and connecting rod assembly of a conventional internal combustion engine in which the piston is directly in line with the crankshaft at TDC such that no torque is developed at this point in the engine cycle.

Therefore, it is envisaged that the crankshaft and connecting rod assembly configuration disclosed in this specification may achieve greater torque output from a conventional crankshaft and connecting rod mechanism.

Preferably, the effective combined length of the piston connecting rod and the timing rod is varied throughout its working cycle by up to 10% without increasing the stroke length of the piston within the piston cylinder.

BRIEF DESCRIPTION OF DRAWINGS

Further aspects of the present invention will become apparent from the following description which is given by way of example only and with reference to the accompanying figures in which:

Figure 1 shows a diagrammatic representation of a first preferred embodiment of an internal combustion engine with crankshaft at TDC (0° of rotation);

Figure 2 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 30° clockwise;

Figure 3 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 90°;

Figure 4 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 180°;

Figure 5 shows the same preferred embodiment of Figure 1, but with the crankshaft rotated 270°;

Figure 6 shows the same preferred embodiment of Figure 1, but with the crankshaft rotated 340°;

Figure 7 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 360°;

Figure 8 shows the same preferred embodiment of Figure 1 , but the crankshaft rotated

390°;

Figure 9 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 400°;

Figure 10 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 450°;

Figure 11 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 540°;

Figure 12 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 630°;

Figure 13 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 700°;

Figure 14 shows the same preferred embodiment of Figure 1 , but with the crankshaft rotated 720°;

Figure 15 shows a simulated pressure graph of cylinder pressure/force on a piston versus rotation of crankshaft;

Figure 16 shows a graph of crankshaft output force or torque versus rotation of crankshaft in a conventional internal combustion engine;

Figure 17 shows a graph of crankshaft output force or torque versus rotation of crankshaft in a non displacement engine;

Figure 18 shows the same preferred embodiment as Figure 1 , but with detail of the distance between the piston pin centre and crankshaft journal centre at TDC (0° of rotation);

Figure 19 shows the same preferred embodiment as Figure 18, but with detail of the distance between the piston pin centre and crankshaft journal centre during rotation of 20° clockwise;

Figure 20 shows the same preferred embodiment as Figure 18, but with detail of the distance between the piston pin centre and crankshaft journal centre during rotation of 40° clockwise;

Figure 21 shows the same preferred embodiment as Figure 18, but with detail of the distance between the piston pin centre and crankshaft journal centre during rotation of 60° clockwise;

Figure 22 shows the same preferred embodiment as Figure 18, but with detail of the distance between the piston pin centre and crankshaft journal centre during rotation of 720° clockwise;

Figure 23 shows the same preferred embodiment as Figure 18, but with detail of the distance between the piston pin centre and crankshaft journal centre during rotation of 180° clockwise;

Figure 24 shows a diagrammatic representation of alternative embodiment of a cam operated internal combustion engine with crankshaft at TDC (0° of rotation);

Figure 25 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 15° clockwise;

Figure 26 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 20° clockwise;

Figure 27 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 30° clockwise;

Figure 28 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 60° clockwise;

Figure 29 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 75° clockwise;

Figure 30 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 120° clockwise; Figure 31 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 300° clockwise;

Figure 32 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 320° clockwise;

Figure 33 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 330° clockwise;

Figure 34 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 340° clockwise;

Figure 35 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 350° clockwise;

Figure 36 shows the same preferred embodiment of Figure 24, but with the crankshaft rotated 360° clockwise;

Figure 37 shows a diagrammatic representation of a crankshaft according to a second preferred embodiment of an internal combustion engine;

Figure 38 shows a diagrammatic representation of a second preferred embodiment of an internal combustion engine using the crankshaft shown in Figure 37 with the crankshaft rotated 12° clockwise from TDC (0° of rotation);

Figure 39 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 60° clockwise;

Figure 40 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 100° clockwise;

Figure 41 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 180° clockwise;

Figure 42 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 240° clockwise;

Figure 43 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 300° clockwise;

Figure 44 shows the same preferred embodiment of Figure 38, but with the crankshaft rotated 360° clockwise;

Figure 45 shows a graph of torque output (IbF) versus rotation of crankshaft (rpm) in a standard engine compared to the non-displacement engine of the present invention according to the third preferred embodiment in a first run;

Figure 46 shows a graph of torque output (IbF) versus rotation of crankshaft (rpm) in a standard engine compared to the non-displacement engine of the present invention according to the third preferred embodiment in a second run; and

Figure 47 shows a graph of pressure (lb) versus rotation of crankshaft (rpm) in a standard engine compared to the non-displacement engine of the present invention according to the third preferred embodiment.

SUMMARY OF THE INVENTION

The present invention can achieve an advanced connecting rod lever angle past crankshaft top dead center (TDC) position with the piston at its TDC position in relation to the piston cylinder. In addition the connecting rod is longer in length than a conventional connecting rod which is commonly set at half the length of the stroke. These elements improve torque over an equivalent standard engine. In addition a longer dwell time of the piston at its TDC position as a result of this configuration of the connecting rod and crankshaft improves combustion efficiency of the engine over an equivalent standard engine.

The aim of the present invention is to improve on the areas of standard internal combustion engines which have inherent inefficiencies. The piston head and cylinder designs were considered to be highly developed with little room for substantial efficiency gains. It was considered that the inefficiencies in converting cylinder pressure to output torque lay with the geometric arrangement of the connecting rod and its attachment to the crankshaft which creates poor working angles while there is peak cylinder pressure.

In a conventional internal combustion engine using a piston, crankshaft, and connecting rod assembly, the rotation of the crankshaft causes displacement of the piston or an increase in piston cylinder volume from the crankshaft TDC position during its rotation cycle. This increase in cylinder volume causes a loss of pressure in the piston cylinder and the crankshaft is not able to be easily rotated to get work done from the cylinder pressure as there is no leverage on the connecting rod to work with when the piston is at TDC or (i.e. 0°). Furthermore, there is only a very small connecting rod lever available for getting work done for the next 30° of crankshaft rotation. As the crankshaft rotates and the connecting rod lever angle increases to get more work done, there is a continuous drop in the cylinder pressure throughout a further 60° of rotation which results in minimal pressure remaining for the crankshaft to get work done. Some engine designers have tried to produce a dwell period at piston TDC position by offsetting the crankshaft centre from the centerline of the piston cylinder and have used both short and long connecting rods with this arrangement. However, this arrangement also does not produce a true piston dwell period. The moment the crankshaft is rotated 1 degree the piston moves and displaces volume albeit a small amount.

Also, having a longer connecting rod will allow displacement to be slowed down by a very small amount, but the connection of the connecting rod to the crankshaft attachment centre is delayed until the pressure has dropped in the piston cylinder. Therefore, the longer connecting rod will not stop the displacement of the piston from its TDC position in a conventional engine arrangement.

It is envisaged the non displacement engine of the present invention prevents any change in cylinder volume occurring while the engine is building peak pressure either during the combustion period when peak cylinder pressure is building or when peak pressure has occurred.

DETAILED DESCRIPTION INCLUDING BEST MODES

First Preferred Embodiment

A first preferred form of the present invention in the form of an internal combustion engine is depicted in Figures 1 to 23.

It should be appreciated by those skilled in the art that only the essential components of the engine are shown for clarity and that other components such as valve lifters, electronic control modules, cam belts etc are well known in the industry and need not be described or shown in the specification.

Figure 1 - Crankshaft at TDC (0° of rotation)

With reference to Figure 1 , an engine 100 is shown with rotatable crankshaft 102 in the TDC position 130. A piston 108 is at the top of cylinder 120 and the crankshaft is rotating in a clockwise direction as indicated by arrow 142. The piston 108 is being held in the cylinder 120 uppermost positions with the configuration where the piston connecting rod 106 is connected to crankshaft timing rod 104 which in turn is connected to the crankshaft 102 and rocker arm connecting rod 114. As can be seen, the piston connecting rod 106 and the crankshaft timing rod 104 are no longer vertically aligned as indicated by dotted line 144. This configuration allows the total distance between piston pin centre 146 and crankshaft journal centre 148 to be shortened.

The angle of the connecting rod 106 and the angle of the timing rod 104 are controlled by rocker arm 112 which is attached to crankshaft cam 110. A slide-able surface 132 is configured so that the rocker arm 112 follows cam profile 150 and is free to move on pin 152 which is attached to crankcase 18 and is connected to a rocker arm connecting rod 114. The rocker arm connecting rod 114 controls the angle of the piston connecting rod 106 and the crankshaft timing rod 104 so that the piston 108 will stay at the top of the cylinder 120 while the crankshaft 102 rotates in a clockwise direction as indicated by arrow 142.

As described later in the rotation cycle, inlet valve 124 controls the amount of fuel/air mixture charge introduced into the piston cylinder 108. Exhaust valve 126 opens to allow exhaust gas to discharge from the cylinder 108 after combustion with spark plug 128.

Figure 2 - Crankshaft rotated 30° clockwise

With reference to Figure 2, the crankshaft 102 has rotated in a clockwise direction as indicated by arrow 142 and has reached a rotation of 30° as shown by the crank position 130. The distance between the piston pin centre 146 and the crankshaft journal centre 148 has lengthened due to the straightening effect of the piston connecting rod 106 and the crankshaft timing rod 104. This configuration has allowed the piston 108 to stay in its uppermost position in the cylinder 120. No displacement of the cylinder volume 154 has occurred in the cylinder 120 during the 30° of rotation of the crankshaft 130 as the crankshaft cam profile 150 is dimensioned to move the rocker arm 112 which in turn moves the rocker arm connecting rod 114. This effectively straightens the piston connecting rod 106 and the crankshaft timing rod 104 from the conrod joint 158 to maintain the piston 108 in its uppermost position during this 30° of rotation as indicated by line 130.

During this cycle of rotation, the crankshaft cam 110 moves the rocker arm 112 which in turn pushes the rocker arm connecting rod 114 towards and just past the centerline and the conrod joint 158. As the conrod joint 158 is attached to the piston connecting rod 106 and the crankshaft timing rod 104, this causes the piston connecting rod 106 and the crankshaft timing rod 104 to become more aligned with respect to each other. In conventional internal combustion engines, the crankshaft 102 turning 30 ° would cause the piston 108 to move down the cylinder 120. However, in the non displacement engine, the piston connecting rod 106 and the crankshaft timing rod 104 have effectively lengthened from the crankshaft journal centre 148 and the piston pin centre 146 keeping the piston 108 in its uppermost position in the cylinder 120. At this time the intake valve 124 can be prepared to open as the piston 108 moves down the cylinder 120 to allow air and fuel to enter the cylinder 120 to begin the induction process.

Figure 3 - Crankshaft rotated 90° clockwise

With reference to Figure 3, the crankshaft 102 has rotated 90° in a clockwise direction as indicated by arrow 142. Here, the piston 108 moves down the cylinder 120 and the inlet valve 124 is open and a mixture of air and fuel 134 enters the cylinder. The crankshaft cam profile 150 is configured to allow the rocker arm 112 and the rocker arm connecting rod 114 to keep the piston connecting rod 106 and the crankshaft timing rod 104 in a vertical alignment similar to that of a conventional internal combustion engine.

Figure 4 - Crankshaft rotated 180° clockwise

With reference to Figure 4, the crankshaft 102 has rotated 180° in a clockwise direction relative to Figure 1 as indicated by arrow 142. Here the piston 108 has reached its bottommost position. The intake charge 134 has entered the cylinder 120 and the inlet valve 124 is closed. The crankshaft cam profile 150 is dimensioned to allow the piston connecting rod 106 and the crankshaft timing rod 104 to remain at a required angle to allow compression of the intake air/fuel mixture charge 134 to proceed.

Figure 5 - Crankshaft rotated 270° clockwise

With reference to Figure 5, the crankshaft 102 has rotated 270° relative to Figure 1 as indicated by arrow 142 and is now 90° from its top dead centre (TDC) position as shown by the crank position 130. The crankshaft cam profile 150 is dimensioned to keep the rocker arm 112 and the attached rocker arm connecting rod 114 in the required position so that the piston connecting rod 106 and the crankshaft timing rod 104 are aligned to move the piston 108 towards to top of the cylinder 120 while compression of the intake charge 134 occurs.

Figure 6 - Crankshaft rotated 340° clockwise

With reference to Figure 6, the crankshaft 102 has rotated in a clockwise direction 340° relative to Figure 1 as indicated by arrow 142 and the crankshaft 102 is now 20° before its TDC position as shown by the crankshaft position 130. The crankshaft cam profile 150 is dimensioned to allow the rocker arm 1 2 to move in such a way that through its attachment to the rocker arm connecting rod 114 which is attached to the piston connecting rod 106 and the crankshaft timing rod 104 provides an angle to occur at conrod joint 158 such that the distance between the piston pin center 146 and the crankshaft journal centre 148 is reduced in length. This configuration allows the piston 108 to reach its uppermost position in the cylinder 120 before its TDC position. This position begins a period whereby the piston 108 remains in its uppermost position in the cylinder 120 for the next 50° of crankshaft 102 rotation without moving up or down i.e. no displacement in volume occurs in the cylinder 120.

Figure 7 - Crankshaft rotated 360° clockwise

With reference to Figure 7, the crankshaft 102 has rotated in a clockwise direction a full 360° relative to Figure 1 as indicated by arrow 142 where the piston 108 has now had a dwell of 20° crankshaft 102 position in the uppermost position in the cylinder 120. As the crankshaft 102 has moved to its TDC position 130, the crankshaft cam profile 150 being dimensioned to allow the rocker arm 112 and the rocker arm connecting rod 114 to move in such a way that a greater angle is now evident at the conrod joint 158 where the piston connecting rod 106 and the crankshaft timing rod 104 are connected. At this position the distance between the crankshaft journal centre 130 and the piston pin centre 146 has been reduced further to keep the piston 108 at the uppermost position in the cylinder 120. Following this cycle of rotation, there is a further 30° of crankshaft rotation before the piston 108 will move from its uppermost position in the cylinder 120. The spark plug 128 can be ignited to raise the pressure of the compressed charge 134 to start building cylinder 120 pressure.

Figure 8 - Crankshaft rotated 390° clockwise

With reference to Figure 8, the crankshaft 102 has rotated in a clockwise direction a further 30° since the position shown in Figure 7 and has now rotated a total of 390° relative to Figure 1. The piston 108 has remained in its uppermost position in the cylinder 120 and has not been displaced from its uppermost position for 50° since the position as shown in Figure 6. The piston 108 has remained stationary in the uppermost position in the cylinder 120 owing to the crankshaft cam 110 having a profile 150 that is dimensioned to move the rocker arm 112, the rocker arm connecting rod 114, the attachment conrod joint 158 of the piston connecting rod 106 and the crankshaft timing rod 104 towards and just past the centerline position 156 of engine 100. This configuration allows the distance between the piston pin centre 146 and the crankshaft journal centre 148 to increase in distance. During this cycle the crankshaft 102 is now advanced by 30° indicated by arrow 130 from the TDC position 156 so there is an efficient lever established on the crankshaft 102 while there is high pressure in the cylinder 120.

Figure 9 - Crankshaft rotated 400° clockwise

With reference to Figure 9, the crankshaft 102 has rotated in a clockwise direction a further 10° since the position shown in Figure 8 and has now rotated a total of 400° relative to Figure 1. This is now 40° after crankshaft 102 TDC position as indicated by crankshaft position 130. The crankshaft cam profile 150 is dimensioned so that it has moved the rocker arm 112 and the rocker arm connecting rod 114 to the furthest point past the centre line 156. This results in the piston connecting rod 106 and the crankshaft timing rod 104 to straighten where the distance between the piston pin centre 146 and the crankshaft journal centre 148 is at its greatest. This configuration further delays the travel of the piston 108 down the cylinder 120 from its uppermost position. The pressured gas 162 in the cylinder 120 is still at a relatively high pressure due to only a small displacement of the piston 108 in the cylinder 120 from the TDC position. During this cycle high torque can be achieved from engine 100 with this configuration as the crankshaft 102 has advanced 40° from its TDC position and where an efficient lever on the crankshaft 102 has been established to get work done while the cylinder pressure 162 is higher than would normally be associated with a conventional engine. The crankshaft rotating 40° in a conventional engine would result in a subsequent loss of pressure.

Figure 10 - Crankshaft rotated 450° clockwise

With reference to Figure 10, the crankshaft 102 has rotated in a clockwise direction a total of 450° relative to Figure 1 as indicated by arrow 142 which is now 90° as indicated by crankshaft position 130 from the crankshaft TDC vertical alignment position 144. The piston 108 has moved down the cylinder 120 and the pressured gas 162 in the cylinder is reducing in pressure. The profile of the crankshaft cam 150 is configured to maintain a suitable angle on the piston connecting rod 106 and the crankshaft timing rod 104 to allow work to be performed and produce rotational energy 142.

Figure 11 - Crankshaft rotated 540° clockwise

With reference to Figure 11 , the crankshaft 102 has rotated in a clockwise direction a total of 540° relative to Figure 1 as indicated by arrow 142 which is now 180° from the TDC vertical alignment centre line 144. The pressured gas 162 is now at a low pressure and the piston 108 has reached the bottom of its travel in the cylinder 120. The low pressure gas has now become the exhaust gas 136 that will be discharged from the engine 100. The exhaust valve 126 opens and the crankshaft 102 will continue to turn in the direction as indicated by arrow 142. The crankshaft cam profile 150 is dimensioned to maintain the piston connecting rod 106 and the crankshaft timing rod 104 in a suitable position for the next phase of expelling the exhaust gasses 136 from the engine cylinder 120.

Figure 12 - Crankshaft rotated 630° clockwise

With reference to Figure 12, the crankshaft 102 has now rotated in a clockwise direction a total of 630° relative to Figure 1 as indicated by arrow 142 which is now 90° as indicated by line 30 before the crankshaft vertical TDC alignment position 144. During this cycle, the exhaust gas 136 is expelled by the rising of piston 108 in the cylinder 120 and the exhaust valve 126 remains open. The crankshaft cam profile 150 is dimensioned to maintain the piston connecting rod 106 and the crankshaft timing rod 104 in a suitable angle for pushing the piston 108 towards the top of the cylinder 120 to remove the exhaust gas 136 from the cylinder 120.

Figure 13 - Crankshaft rotated 700° clockwise

With reference to Figure 13, the crankshaft 102 has now rotated in a clockwise direction a total of 700° relative to Figure 1 as indicated by arrow 142 and is now 20° before the TDC crankshaft vertical alignment position 144. The piston 108 has now reached its uppermost position in the cylinder 120. The exhaust gas 136 has been expelled from the cylinder 120 and the exhaust valve 126 is now closed. This is the beginning of the 50° dwell 164 while the crankshaft 102 rotates 50° where the piston 108 will remain in its uppermost position in the cylinder 120 without any displacement occurring. The crankshaft cam profile 150 is dimensioned so as to create an angle to form at the pin attachment 158 for the piston connecting rod 106 and the crankshaft timing rod 104. As previously described, the distance between the piston pin centre 146 and the crankshaft journal centre 148 will continue to decrease in length to keep the piston 108 in its uppermost position during the next 20 degrees of rotation of the crankshaft 102. For the next 30 degrees of crankshaft rotation 142 (see also Figure 8), the distance between the piston pin centre 146 and the crankshaft journal centre 148 will increase in length to keep the piston 108 stationary in its uppermost position in the cylinder and prevent the piston 108 from moving up or down in the cylinder 120 while the crankshaft 102 rotates during this cycle.

Figure 14 - Crankshaft rotated 720° clockwise

With reference to Figure 14, the crankshaft 102 has rotated in a clockwise direction a total of 720° relative to Figure 1 as indicated by arrow 142 which completes one cycle of rotation. The engine 100 shows the crankshaft 102 in the common TDC 130 position. The piston 108 is still at the top of the cylinder 120 and is being held in the cylinder 120 uppermost position by the configuration where the piston connecting rod 106 is connected to the timing rod 104 which in turn is connected to the crankshaft 102 and the rocker arm connecting rod 114 as previously described. The piston connecting rod 106 and the crankshaft timing rod 104 are angled as a result of the crankshaft cam profile 150 and assembly as previously described.

The angle of the connecting rod 106 and the angle of the timing rod 104 are controlled by the rocker arm 112 which is attached to the crankshaft cam 1 0. A slide-able surface 132 is configured so that the rocker arm 112 follows the cam profile 150 and is free to move on pin 152 which is attached to the crankcase 118 and is connected to the rocker arm connecting rod 114. The rocker arm connecting rod 114 controls the angle of the piston connecting rod 106 and the crankshaft timing rod 104 so that the piston 108 will stay at the top of the cylinder 120 while the crankshaft 102 rotates in a clockwise direction as indicated by arrow 142. It should be appreciated by those skilled in the art that the period of dwell or non displacement shown in this preferred embodiment is up to 50°. However, this should not be seen as a limitation on the embodiments envisaged for this invention and other engine configurations may conceivably result in up to 90° period of dwell as a result of modifications in the crankshaft cam profile 150 and/or lever lengths.

The movement of the rocker arm 112 in relation to the rocker arm connecting rod 114 is minimal to minimize frictional losses. Frictional losses are incurred as the slide-able surface 132 moves over the cam profile 150 and in the bearings (such as conrod joint 158).

Example 1: Comparison of performance of conventional engine versus non displacement engine according to first preferred embodiment

In order to demonstrate the theory of the non displacement engine, two engine models were built of the same capacity and stroke. One model was that of a conventional engine and the other a non displacement engine. These two models were used to provide data to confirm if there would be any output gains over conventional engine technology, for example to test whether or not the non displacement engine of the present invention could produce more power from the same pressure in the cylinder during the working cycle from TDC position to 90° after TDC position.

First, a simulated pressure graph was created that gave a measurement of cylinder pressure or force on the piston of the two models. On the simulated pressure graph, peak pressure was applied at 10° after TDC position (as is commonly seen in engines so as to not disadvantage the convention engine over the non displacement engine technology).

This simulated pressure graph was then converted to grams in weight, so that an appropriate weight could be applied to the top of the piston from TDC position through to 90° after TDC position. Care was taken throughout this procedure to ensure that the piston and connecting rod assembly of each model was balanced to a neutral state. This was to avoid the issue of an extra application of force being applied to the crankshaft or reduction in output as a result of engine imbalance for each model.

Figure 15 shows the simulated pressure graph that was used to calculate and test the two models for output torque from the crankshaft.

The two engine models were tested by a simple arm of a given length being attached to the crankshaft, and the arm was able to be moved in increments of 10° starting from TDC position to 90° after TDC position. This arm was configured with a sharp pivot point at the end which was placed on a digital scale to obtain a readout in grams. For example, Figure 15 shows 600 grams of weight placed on top of the piston at TDC position and 700 grams of weight at 10° after TDC position and so on.

Conventional engine test results

With reference to Figure 16, the conventional engine model was tested using the above method of placing a known weight on top of the piston and then reading the weight (or equivalent recovered torque) from the digital scale. This method is effectively a type of dynamometer to demonstrate the work done by the crankshaft from a known weight placed on top of the piston. The output graph showed no work was achieved at TDC position when the weight of 600 grams was placed on top of the piston. At 10° after TDC position when the peak amount of 700 grams of weight was applied to the top of the piston, approximately 18 grams of feree was produced as torque from the crankshaft. The output gradually improved as a more efficient working angle appeared on the crankshaft to get work done.

Non displacement engine test results

With reference to Figure 17, the testing of the non displacement engine model according to the first preferred embodiment of the present invention was conducted to find the comparative difference between existing piston, crankshaft and connecting rod assemblies of conventional engines and the non displacement engine design. Although the non displacement engine utilises existing piston, crankshaft and connecting rod componentry, the difference with the non displacement engine over a conventional engine set up is that modifications have been made to the configuration of the crankshaft and connecting rod assemblies as previously described. In fact, the connecting rod still has a fixed wristpin application to the piston and a solid attachment to the crankshaft journal as per a conventional engine. However, modifications to the crankshaft and connecting rod assemblies gives a modified expansion cycle to get work done which results in the following differences and allows for more torque to be produced from the crankshaft:

1. The piston rises to its TDC position as per a conventional engine, but then dwells for a period of 40 degrees of rotation of the crankshaft without displacing the piston from the TDC position. This design configuration allows a more complete combustion cycle that begins with the piston starting its dwell cycle, with no alteration of combustion shape or capacity during the entire combustion period.

2. This 40 degrees of piston dwell allows the crankshaft to advance to a given position so that at the end of the dwell period of the piston, there is now a more efficient working lever on the crankshaft to get more work done while there is peak pressure in the cylinder relative to a conventional engine design. 3. As there is a dwell of 40 degrees where the piston does not move from its TDC position, the crankshaft connecting rod big end journal centre point, or the length of the lever on the crankshaft is required to be lengthened to compensate for this loss of linear motion. For example, if an engine had a stroke of 86 mm, the throw on the crankshaft would need to be 43 mm offset from the centerline of the crankshaft. The non displacement engine design requires the lever to be lengthened by 48.12mm (12%) so that the same stroke of 86 mm is achieved. The resulting configuration also contributes to the increased output of the engine relative to conventional engine design.

Demonstration of the varying distance between the piston pin centre and crankshaft journal centre during rotation and piston dwell

Figure 18 shows the piston at TDC position where the crankshaft journal is inline with the centre of the piston. The engine is configured with 2 connecting rods joined at the centre each with a length of 96.5 mm, the total length of the connecting rods being 193 mm. Since the 2 connecting rods are angled the distance between the piston wrist pin and the crankshaft journal centre is 161.64 mm.

Here the piston on arrival at the TDC position (at the top of the cylinder) stays at the uppermost position for a given period of dwell without displacing any volume. This allows the crankshaft to advance to where it has a good working angle and a large working lever to better utilise the pressure in the cylinder to get more work done.

A conventional engine arrangement has no lever to work with at the TDC position, and when most conventional engines achieve peak pressure in the cylinder, the lever of the crankshaft is minimal.

The non displacement engine can keep the piston stationary at the top of the cylinder for a set period of rotation of the crankshaft from 1° to 90° after the crankshaft has become vertically aligned with the centre piston wrist pin by virtue of the conjoint arrangement of the connecting rods (see also figures 1 to 14 where one of the connecting rods also has been referred to as a timing rod). As aforementioned, as the piston dwells at the uppermost position in the cylinder for a set rotation of the crankshaft, the crankshaft can rotate in a given direction for a set period of time without any displacement in the cylinder taking place.

Since the crankshaft can rotate in a given direction for a set period whereby the piston remains in the uppermost position (TDC), the lever length of the crankshaft in the non-displacement engine is configured to become longer than that would expected in a conventional engine arrangement. It is well known by those skilled in the art that the levers on a crankshaft where the connecting rod is attached to are set in their length to produce the stroke of an engine. For example, if the lever on a crankshaft is 40 mm, then the stroke produced in the cylinder would be 80 mm. It should be noted that some engine designs can have variable strokes, but in these engines the length of the crankshaft lever is what sets the maximum stroke in the cylinder.

Since the non-displacement engine is configured to allow the crankshaft to rotate and keep the piston in the uppermost position in the cylinder for a designated period, the rotation of the crankshaft is no longer producing stroke in the cylinder. To compensate for this loss of stroke in the cylinder, the lever length of the crankshaft journal where the connecting rod is attached is required to be lengthened. This increase in the lever length of the crankshaft connecting rod journal may be increased from 10% to 45% in length. This lengthening of the working lever of a crankshaft can beneficial to produce more torque from the pressure in the cylinder and is shown in Figures 19 to 23 as follows:

Figure 19 shows that the crankshaft has rotated 20° and the piston is still at its TDC position. The distance between the piston wrist pin centre has lengthened to 164.63 mm.

Figure 20 shows that the crankshaft has rotated 40° from the vertical position as shown in Figure 18. The piston is still at the top of the cylinder at TDC position. With the 2 connecting rods becoming more aligned the distance between the piston writs pin and the crankshaft journal centre has now lengthened to 172.99 mm.

Figure 21 shows that the crankshaft has rotated 60° from the vertical position as shown in Figure 18. There has been no displacement occurring in the cylinder and the piston is still at TDC position. It can be seen that as the 2 connecting rods are becoming straighter, the distance between the piston wrist pin centre and the crankshaft journal centre has now lengthened to 184.90 mm.

Figure 22 shows that the crankshaft has rotated 72° from the vertical position as shown in Figure 18. The piston is still at the top of the cylinder at TDC position, but the engine is now ready to start displacing volume with the turning of the crankshaft. The 2 connecting rods have become aligned with each other so now the length between the piston wrist pin centre and the crankshaft journal centre is at its maximum length of 193 mm.

Figure 23 shows that the crankshaft has rotated 180° and full displacement of the cylinder has taken place. As shown in Figures 18 to 23, the crankshaft journal centre is 40 mm from the centre of the crankshaft where rotation occurs. This 40 mm throw on the crankshaft journal centre would normally produce 80 mm of stroke in the cylinder, but because the crankshaft has rotated 72° without producing any linear stroke, the crankshaft journal centre needs to be lengthened giving the crankshaft a larger lever to compensate. For example, the lever on the crankshaft is lengthened to 55.68 mm to compensate for this loss of vertical linear motion. This is an increase of more than 39% which also increases the torque output of the engine.

Second Preferred Embodiment

Figures 24 to 36 show an alternative engine configuration configured to slow the piston travel down through TDC position in addition to the ability to hold the piston at the TDC position of the stroke for a predetermined angle of rotation of the crank shaft.

In this embodiment the piston is substantially slowed down in its travel to achieve a greater angle on the crankshaft to provide a better working lever relative to a conventional engine while comparatively higher working pressure is still present in the cylinder.

The applicant has found that they can achieve this advantage by utilising a milder crankshaft cam profile and altering the geometry of the connecting rod and rocker arm assemblies. A further advantage of using a milder cam profile is that less work is expended leading to a more fuel efficient engine.

This alternative engine configuration retains the existing crankshaft 102 as would be found in a conventional engine along with a connecting rod or timing rod 104. However, a second connecting rod 106 links with a rocker arm 112 and is joined to the top of the timing rod 104 which in turn is attached to the piston 108.

A crank shaft cam 110 can be profiled or shaped to provide counterbalance on the crankshaft 102 or as with a conventional engine, a counterweight can be utilised on the crankshaft 102 to balance the engine during rotation to achieve the same result.

In this embodiment, the crankshaft cam 110 is attached to the crankshaft webbing 167 or is positioned on an offset shaft which is turned by the crankshaft 102 with its counterweight (normally found between the crankshaft big end and the main bearings). Either of these two configurations controls the height of the piston 108 as it moves towards and away from its TDC position.

The crankshaft cam profile 150 is configured to cause the piston 108 to dwell at TDC position for a number of degrees during crankshaft 102 rotation. This dwell period ranges from 1-90°.

A purpose of the crankshaft cam profile 150 is that it can slow down the piston 108 from TDC position and after TDC position so an efficient working angle on the crankshaft 102 resulting in work done while there is still high pressure in the cylinder. Furthermore, the crankshaft cam profile 150 is configured to speed up the piston 108 travel from compressing an incoming charge of air to reach TDC position or as above, the crankshaft cam profile 150 slows down the piston as it travels towards TDC position. It should be appreciated by those skilled in the art that the crankshaft cam profile 150 can be shaped or dimensioned depending on what engine characteristics are required for any given application without departing from the scope of the present invention.

In this embodiment, attached to the top of the timing rod 104 is another connecting rod or rocker connecting rod 114. This in turn is attached to the rocker arm 112. The bottom end of rocker arm 112 includes a bottom arm 165 with a bearing 132 at one end and a rod 168 that fits into a slide known as the rocker slide 166. This configuration keeps the rocker arm 112 substantially parallel to the centre axis of the crankshaft 102. The bearing 132 on the bottom arm 165 runs on the crankshaft cam profile 150.

The above engine geometry allows an efficient working lever to be established on the crankshaft 102 relative to a conventional engine resulting in more work being done while there is still high pressure in the cylinder.

The embodiment shown in Figures 24-36 is an exemplary configuration which utilises a 40 mm throw on the crankshaft 102 while providing a 73 mm of stroke. The operation of this smaller capacity engine is now described further below.

Figure 24 - Crankshaft at TDC position (0° of rotation)

With reference to Figure 24, an engine is shown with crankshaft 102 in its uppermost position. A piston 108 is at TDC position and the crankshaft 102 is rotating in a clockwise direction. The connecting rod 106 and timing rod 104 are angled and retained in position by the rocker arm 112 assembly. The crankshaft cam 110 keeps which is attached to the bottom arm 165 and can move according to the cam profile 150 by being able to slide into the rocker slide 166.

Figure 25 - Crankshaft rotated 15° clockwise

With reference to Figure 25, the crankshaft 102 has turned clockwise in the direction of the arrow 142 by 15 degrees, and the profile of the crankshaft cam 110 has caused the connecting rod 106 and the timing rod 104 to straighten. This configuration has kept the piston 108 in its uppermost position in the cylinder 120.

Figure 26 - Crankshaft rotated 20° clockwise

With reference to Figure 26, the crankshaft 102 has turned 20 degrees clockwise in the direction of the arrow 142 and the piston 108 is just starting to move from the top of the cylinder 120 and has finished its dwell period. Since the rocker arm 112 is attached to the bottom arm 165 with its bearing 132, it is now travelling on a set radius on the crankshaft cam 110 and there will be no movement of the rocker arm 112 for the next 80 degrees.

Figure 27 - Crankshaft rotated 30° clockwise

With reference to Figure 27, the crankshaft 102 is turning clockwise in the direction of the arrow 142 by 30.30 degrees, the crankshaft cam 110 has caused the connecting rod 106 and the timing rod 104 to straighten further and it has kept both the piston 108 near the top of the cylinder 120 and the pressure 162 high in the cylinder 120 while the crankshaft 102 now has an efficient working angle to get work done.

Figure 28 - Crankshaft rotated 60° clockwise

With reference to Figure 28, the crankshaft cam 110 with the bottom arm bearing 132 and the bottom arm 165 (and as previously described for the previous engine embodiment) has now caused the connecting rod 106 and the timing rod 104 to become almost parallel with the crankshaft 102 having turned clockwise 60 degrees in the direction of the arrow 142. This has kept the piston 108 high in the cylinder 120 and there is still good pressure 162 to get work done. The bottom arm 165 being concentric with the rocker slide 166 keeps the bottom arm 165 substantially parallel to the crankshaft axis.

Figure 29 - Crankshaft rotated 75° clockwise

With reference to Figure 29, the crankshaft 102 has rotated 75.04 degrees clockwise in the direction of arrow 142. Here the cylinder pressure 162 is approximately the same as a conventional engine would have at 60 degrees rotation using the same connecting rod 106 and timing rod 104 length joined together as per a single connecting rod. The crankshaft cam 110 will keep the connecting rod 106 and the timing rod 104 parallel with respect to each other to minimise the frictional losses during the turning of the crankshaft 102 for the rocker arm assembly 112, 165 and 166 working against the crankshaft cam 110.

Figure 30 - Crankshaft rotated 120° clockwise

With reference to Figure 30, the crankshaft 102 continues to turn in a clockwise direction indicated by arrow 142 and the crankshaft cam 1 0 profile keeps the connecting rod 106 and the timing rod 104 parallel by adjusting the rocker arm assembly 112, 132, 165 and 166.

Figure 31 - Crankshaft rotated 300° clockwise

With reference to Figure 31 , by the time the crankshaft 102 has travelled 300 degrees from TDC position or is now 60.96 degrees before TDC position, the crankshaft cam 110 profile has started to cause the connecting rod 106 and the timing rod 104 to begin to angle. This will cause the piston 108 to start to slow down in its travel towards the top of the cylinder 120. The bottom arm 165 and the rocker slide 166 allows the rocker arm 112 to move freely.

Figure 32 - Crankshaft rotated 320° clockwise

With reference to Figure 32, with the crankshaft 102 now having rotated 320 degrees from TDC position or is now 40.01 degrees before TDC position, the crankshaft cam 110 profile has caused the rocker arm 112 assembly 165 and 166 to move the connecting rod 106 and the timing rod 104 to a more angled position causing the piston 108 to slow as it nears the top of the cylinder 120.

Figure 33 - Crankshaft rotated 330° clockwise

With reference to Figure 33, further angles on the connecting rod 106 and the timing rod 104 has occurred with the crankshaft 102 now having rotated 330 degrees clockwise 142 and is now 30.50 degrees before TDC position. This again has slowed the piston 108 as it nears the top of the cylinder 120.

Figure 34 - Crankshaft rotated 340° clockwise

With reference to Figure 34, as the piston 108 nears the top of the cylinder 120, the crankshaft cam 110 profile with the bearing 132 and the bottom arm 165 and the rocker arm 112 has caused the connecting rod 106 and the timing rod 104 to be at a greater angle which has almost slowed the piston down for the TDC position in the cylinder 120.

Figure 35 - Crankshaft rotated 350° clockwise

With reference to Figure 35, with the crankshaft 102 positioned at 10.66 degrees before TDC position. The piston 108 is now almost stationary. The rocker arm 112 and the bottom arm 165 with its bearing 132 rolling against the cam 110 has pulled the connecting rod 106 and the timing rod 104 nearly to its greatest angle. The rocker slide 166 allows for this movement.

Figure 36 - Crankshaft rotated 360° clockwise

With reference to Figure 36, the crankshaft 102 has now completed a full turn in a clockwise direction indicated by arrow 142. Here, the piston 108 will begin its dwell time at the top of the cylinder 120. The connecting rod 106 and the timing rod 104 are now at its most angled position. The crankshaft cam 110 profile will keep this angle for the dwell period of the piston 108 for approximately 20 degrees to allow the crankshaft 102 journal to advance to an efficient working angle while the cylinder pressure is high. Rocker arm 112, bottom arm 165, bottom arm bearing 132 and rocker arm slide 166 all manage to work together to achieve this geometry. Third Preferred Embodiment

A third preferred form of the present invention in the form of an internal combustion engine is depicted in Figures 37 to 44. This embodiment is an exemplary configuration which utilises a 44.65 mm throw (or crank offset distance) on the crankshaft 102 with a connecting rod length of 151.25 mm while providing 82 mm of stroke.

Figure 37- Crankshaft

In Fig 37 a crankshaft 100 for a single cylinder is shown with an offset journal 149 for attachment of the connecting rod (not shown) where offset journal 149 center 148 is offset from the crankshaft center axis 165 by 44.65 mm (151 ). The stroke of the engine 100 is set at 82 mm. Conventional engines have the offset connecting rod journal center 148 from the crank center 165 set at 41 mm if the cylinder was to have a piston to travel its full distance of 82 mm but the non-displacement engine of the present invention uses a longer lever without forming additional stroke. This longer effective offset connecting rod journal allows the engine of the present invention to produce more torque without producing more piston travel.

The crankshaft balance webbing 103 is used to balance the engine. The crankshaft 100 also has webbing cams 110 and 111 as part of the crankshaft arrangement. It is the crankshaft webbing 110 and 111 that controls the piston height in the cylinder and how much piston travel is achieved in the cylinder.

Figure 38- Crankshaft rotated 12° clockwise

In Fig 38 the crankshaft 102 is positioned at 12 degrees 130 after the crankshaft 102 TDC position and the piston 108 has now reached its uppermost position in the cylinder 120 at piston TDC position 01.

The connecting rod 106 and the timing rod 104 are at an angle from the vertical line that runs from the crankshaft center 149 to the piston pin center 146. The connecting rod and timing rod are held in their angled position by means of a rocker arm 114 that is attached to a rocker 112. This rocker 112 pivots on a pin 152 and has at the bottom a flexible join 155 that allows the rocker 112 to move in any direction it needs to move. The flexible join 155 is connected to the rocker slider 153. The rocker slider 153 is kept in its proper position by the slider base 163 and sliding surfaces or bearings 154 that are in contact with the crank webbing 110 and 111. The crank webbing 110 and 111 have a cam profile 150 that controls the piston height and motion as the piston 108 travels up and down the cylinder 120. The 12 degree angle of the crankshaft produces more toque than would normally be had in a engine from the cylinder 120 pressure.

Figure 39- Crankshaft rotated 60° clockwise In fig 39 the crankshaft 102 has now traveled 60 degrees from its TDC position moving 142 in a clockwise direction. The piston 108 has traveled down the cylinder 120 and the connecting rod 106 and the timing rod 104 are becoming straighter and not being so angled.

Frictional losses have been kept low due to the rocker slider 153 having sliding surfaces or bearings 154 in contact with the crankshaft cams 110 and 111. The crank cams 110 and 111 have a perfect radius so the sliding surfaces or bearings 154 in contact with the cam profile 150 has limited amount of work to be done. It is during this phase that the rocker slider 153 and the rocker 152 which is connected to the rocker arm 114 have no movement for 90 degrees of crankshaft rotation.

Figure 40- Crankshaft rotated 100° clockwise

The crankshaft 102 has rotated in a clockwise direction 142 and has now traveled 100 degrees from its TDC position 130. From the piston 08 TDC position and the distance it has traveled in the cylinder 120 the rocker 112 and the rocker slider 153 have not moved as the sliding surface or bearings 154 have been in contact with the crank cams 110 and 111 and up to this point there has been a perfect radii for the sliding surfaces or bearings 154 to work on. The rocker arm 114 has been motionless where it is attached to the rocker 112 except it has moved down in position where it joins the center of the connecting rod 106 and the timing rod 104. This motion of the stationary rocker slider 153 and the rocker 112 being fixed to the connecting rod 106 and the timing rod 104 by means of the rocker arm 114 has caused the connecting rod 106 and the timing rod 104 to become aligned with each other. This straightening of the connecting rod 106 and the timing rod 104 has slowed down the piston 108 travel in the cylinder 120.

Figure 41- Crankshaft rotated 180° clockwise

The crankshaft has turned 142 180 degrees 130 to where the piston 108 has reached the bottom of the cylinder 120. The motion of the rocker 112 and the rocker slider 153 being held in its correct position by the rocker slider base 163 and the sliding surfaces or bearings 154 being held by the crank cams 110 and 111 has kept the connecting rod 106 and the timing rod 104 in a vertical or aligned position.

Figure 42- Crankshaft rotated 240° clockwise

The crankshaft 102 turning in the direction of arrow 142 and it is now at 120 degrees 130 before its TDC position. The piston 108 is now travelling up the cylinder 120. The connecting rod 106 and the timing rod 104 are still parallel to each other. This parallel configuration is managed by the rocker arm 114 being attached to the rocker 112 which is attached to the rocker slider 153 by means of the flexible join 155. The sliding movement of the rocker slider 153 is managed by the crank cams 110 and 111.

Figure 43- Crankshaft rotated 300° clockwise

Fig 43 shows the crank 102 having traveled to 60 degrees 130 before its TDC position. The piston 108 is now nearing the top of the cylinder 120. At this crank angle the connecting rod 106 is held vertical while the timing rod 104 is moving the piston 108 higher in the cylinder 120. The rocker slider is being influenced by the cams 110 and 111 which move the rocker 112 accordingly and by means of the rocker arm 114 the connecting rod 106 and the timing rod 104 are kept in an acceptable position.

Figure 44- Crankshaft rotated 360° clockwise

The crankshaft has now reached its TDC position but the piston 108 has further distance to travel in the cylinder 120 to reach its TDC position 101. It is not until the crankshaft has traveled past its TDC position by another 10 degrees after TDC position will the piston 108 reach its topmost position in the cylinder 120. The higher torque produced by the engine of the present invention is due to the fact that the crank angle remains advanced over a normal engine. This advanced crank angle is managed by the crank cams 110 and 111 whereby the sliding surfaces or bearings 154 are moved accordingly to the shape of the cams 110 and 111. These surfaces 142 being attached to the rocker slide 153 move the rocker 112 and the rocker arm 114 so that the connecting rod 106 and the timing rod 104 are positioned in such a way as to raise or lower the piston during part of the cycle.

Example 2: Comparison of performance of conventional engine versus non displacement engine according to third preferred embodiment

With reference to Figure 45 the torque output (newton meters) of a standard engine compared to the non-displacement engine of the present invention according to the third preferred embodiment is shown. At 1200 rpm and 14.2% throttle position the results show a 49% improvement in torque output. With reference to Figure 46 at 1200 rpm and 14 % throttle position the engine of the present invention shows a 49% improvement in torque output over a standard engine. 1200rpm simulates a light throttle setting.

With reference to Figure 47 at 2000 rpm and 100% throttle position the engine of the present invention shows a 35% improvement in torque output over peak torque of a standard engine at 14 % throttle position and 1200 rpm. 2000 rpm simulates a full throttle setting.

Figures 45 to 47 show that the engine of the present invention has a greater improvement in torque over a standard engine with a light throttle setting. As most engines operate in a light throttle position for most of their running life the improved efficiency of the engine of the present invention will be have a greater advantage.

Those skilled in the art will appreciate that the extra torque generated from the gains shown in Figures 45 to 47 are much higher in real world use as the increased torque will allow lower RPM of the engines and less time under full acceleration. The engine of the present invention will likely achieve higher efficiency gains of in excess of the 50%.

Advantages of the non displacement engine of the present invention over a conventional engine

• There is a period of dwell where the piston stays at the top of the cylinder during the combustion period. This results in a more efficient combustion. In particular, by the piston not falling down the cylinder as in a conventional engine during this combustion period, the pressure rise may be greater causing the carbon molecules to become in closer contact with the oxygen molecules resulting in better oxidization and more complete combustion which results in improved efficiency.

• The piston dwelling at the top of the cylinder allows non displacement of the piston while the crankshaft continues to rotate. This produces a more efficient lever relative to a conventional engine resulting in work done while there is still high pressure in the cylinder. Therefore, more torque output may be produced from the engine.

• As there is no displacement taking place during the dwell period where the piston remains at the top of the cylinder for a set period of time, the crankshaft continues to rotate which allows a larger throw on the crank journal to produce a set stroke of an engine. For example, if the crankshaft journal is manufactured at a length of 56.6 mm (as shown in Figures 1 - 14) the stroke of the engine would usually be 132.20 mm. However, as the piston is not displacing any volume for a period of 50 degrees of crankshaft rotation, the stroke has decreased by 10 mm to 122.20 mm. A lever length of 10% longer can be used to return the stroke to the equivalent length of 132.20 mm. A longer lever may produce more torque from the engine, but will not increase the stroke.

• Unlike other engines which utilise a flexible connecting rod, the non displacement engine uses an adjustable connecting rod assembly to cause a stationary period for the piston to dwell at TDC position during the time of the complete combustion process of an engine. This dwell time is adjustable by altering the geometric arrangement of the crankshaft cam and the lever lengths and fastening positions to suit different sizes and types of engines. • Furthermore, the non displacement engine uses the adjustable connecting rod assembly to allow the crankshaft to advance to a more efficient working angle and hence lever to produce rotational force while there is peak pressure in the cylinder. Again, the amount of lever length that can be achieved is easily adjustable by altering the geometric arrangement of the crankshaft cam and the lever lengths and fastening positions of the levers to suit different sizes and types of engines.

• In view of the connecting rod and crankshaft mechanism of the present invention being mechanical in operation, improved reliability over electrically operated piston displacement engines.

• Relatively low cost of production in that the engine of the present invention uses standard piston and cylinder technology with a modified connecting rod and crankshaft. In addition, the piston speed of the engine of the present invention is similar to the piston speed of standard engines resulting in a similar piston wear rate. The modification to the crankshaft is relatively minor consisting of changes to the attachment points of the connecting rod to the crankshaft.

In summary, the applicant's invention includes a crankshaft and connecting rod assembly configured to slow piston travel through top dead centre position of a stroke cycle or hold the piston at the top dead centre position for a predetermined angle of rotation of the crankshaft. This allows peak pressure to occur while a more efficient lever length is established on the crankshaft to produce more torque.

It should be appreciated by those skilled in the art that other variations which achieve the above principle may include but are not limited to a one way clutch mechanism with a secondary Output shaft. Also, an engine which includes a moving head operated by a rocker on top of a piston such that the moving head is timed to the piston so that peak pressure occurs when the connecting rod connected to the crankshaft has an efficient working lever. A further variant may include a moveable piston top based on top of a piston body where cam, levers or electronic mechanisms may be used to keep the piston top at peak pressure until an efficient working angle is established on the crankshaft.

It should also be appreciated by those skilled in the art that the description and drawings show crankshaft rotation in a clockwise direction. However, the engine may conceivably be configured to operate in an anti-clockwise direction.

Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope thereof as defined in the appended claims.

Claims

WHAT WE CLAIM IS:

1. An internal combustion engine comprising:

• a rotatable crankshaft comprising a crankshaft cam surface; and

• a connecting rod assembly comprising:

o a piston connecting rod pivotally connected at one end to the piston; and

2. An internal combustion engine as claimed in claim 1 wherein the rocker arm is connected to the conrod joint via a rocker arm connecting rod connected to the conrod joint at one end and the rocker arm at another end.

3. An internal combustion engine as claimed in claim 2 wherein the rocker arm is connected to the conrod joint at an angle of less than 90 degrees.

4. An internal combustion engine as claimed in claim 1 wherein the working crank angle between the piston connecting rod and the crankshaft timing rod is between 0.1° to 40° where the piston is held at its TDC position.

5. An internal combustion engine as claimed in claim 4 wherein the working crank angle between the piston connecting rod and the crankshaft timing rod is between 10° to 15° where the piston is held at its TDC position.

6. An internal combustion engine as claimed in claim 5 wherein the working crank angle between the piston connecting rod and the crankshaft timing rod may be may be 12° where the piston is held at its TDC position.

7. An internal combustion engine as claimed in any one of claims 1 to 6 wherein the effective combined length of the piston connecting rod and the timing rod is varied throughout its working cycle by up to 10% without increasing the stroke length of the piston within the piston cylinder.