FIELD OF INVENTION

[0001] The present invention relates to a cylinder head gasket for an internal combustion engine and more particularly to a gasket for mating the air intake manifold and the cylinder head.

BACKGROUND OF INVENTION

[0002] A gasket for mating two metallic components typically uses a thin material sandwiched between two components. This way the gasket material already occupies the irregular space between the two component's surfaces, from where the material passing through the two components could have leaked. Hence, there is no scope for the material passing through the two components to leak out from the said mating surfaces.

[0003] The above principle of gasket functioning is used to provide an enhanced sealing effect for the passage of fluids (including both air and liquids) through two components which are joined together.

[0004] The leak proofness of the joints depends up on the surface flatness achieved on the two mating parts. Various gaskets are being used in the industry for providing leak proofness in the joints of two components. A better leak proofness may be achieved by using a better gasket material, using various beading effect on the gaskets, using beads and the beading mechanism on the mating components, or by using plurality of gasket members on the mating components.

SUMMARY OF THE INVENTION

[0005] The current invention discloses a gasket used between intake pipe and cylinder head to arrest air leakage. Leakage from the air intake manifold may take place due to irregular pitch of mounting bolts. In addition to that, the surface roughness and flatness variation on the mating surfaces of the mating components also lead to leakage. The current invention provides a better sealing effect between the air intake manifold of an internal combustion engine and the cylinder head of the internal combustion engine by using a mating gasket characterized by following two characteristics.

[0006] The first characteristic of the disclosed gasket is that the said gasket has headings formed circumferentially on both the sides. The second characteristic of the gasket is that the beading on one side of the gasket is having an offset by a pre­determined distance from the circumference of the aperture of the gasket with respect to the beading on the other side. The gasket in the current invention is preferably formed with silicone rubber beading on both faces, which ensures the efficient leak proof ness of the mating j oint.

BRIEF DESCRIPTION OF DRAWINGS

Figure 1 illustrates a typical motorcycle.

Figure 2 illustrates the mating of cylinder head and air intake manifold of an engine.

Figure 3 illustrates the gasketting of the air intake manifold.

Figure 4 illustrates the two sides of the gasket and the headings there upon.

Figure 5 shows the cross section of the gasket with the profile of two headings facing the air intake manifold side.

DETAILED DESCRIPTION OF THE INVENTION

[0007] The current invention discloses an efficient sealing achieved between the joint at air intake manifold and the cylinder head of the internal combustion engine by using beading on gasket. The two headings on the sealing material are deformed according to the need of the mating surfaces to block all the passages for the air to pass through the minute gap between the surfaces of the mating components. An advantage with this two beading system as disclosed in the current invention is that, in extreme case of breaking of the inner bead facing the cylinder head, the beading facing towards the air intake manifold presses the said gasket and achieves the desired sealing effect.

[0008] The sealing effect as disclosed in the current invention is achieved by sandwiching a sealing material (gasket) in-between the air intake manifold and the cylinder head of the internal combustion engine. Both the sides of the sealing material are equipped with a circumferential beading, placed at a predetermined distance from the periphery of the aperture of the sealing material. This aperture is used for the passage of air through the said manifold.

[0009] The location of the headings on both the sides of the sealing material is also an essential element of the current invention wherein the beading on both the faces of the sealing material, are located with a pre-determined offset. The distance being such that, the cylinder head side beading is located at a larger distance from the outer periphery of the aperture of the intake manifold.

[00010] Figure 1 shows a motorcycle 11 comprising of a fuel tank 12, an engine 13, and an exhaust muffler 14. The fuel from the fuel tank 11 that enters engine 13 undergoes combustion inside the cylinder from which generated mechanical power is transferred to a wheel 15. Since, combustion of fuel is an exothermic reaction; a large amount of heat is generated in this process. Also as shown in Figure 1, one end of the exhaust muffler 14 is connected to the exhaust port of the engine 13. This exhaust port is located on the cylinder head 17 of the said engine 13. The exhaust gas passes through a catalytic converter 16, which is placed inside the exhaust muffler 14. The carrying away of burnt and unburnt gases during combustion through the exhaust muffler, increases its temperature and consequently the exhaust muffler attains a very high temperature while the vehicle is in use. The air induction and the exit of exhaust gases form a very important section of such a motorcycle.

[00011] Figure 2 shows the cylinder head 17 with the exploded view of mating portion of the air intake manifold 22 with the cylinder head. In the figure 2, the passage of air through the aperture 21 passes through the apertures on the sealing material 24 and finally enters into the aperture 25 on the cylinder head 17. The mating part 23 on the cylinder head 17 and the portion labeled 22 form the mating part and inbetween these two mating parts 23 and 22, resides the sealing material 24.

[00012] Figure 3 shows the sealing material 24 with the side of the sealing material facing the cylinder head. The sealing material 24 also has a beading element 31 located in a circumferential direction of the aperture at a pre determined distance from the sides of the aperture. The two apertures 32 on the sealing material 24 mate and coincide with the two apertures 33 on the air intake manifold 22 when they are assembled and tightened with the fasteners.

[00013] Figure 4 shows the two sides of the sealing material 24. The side labeled 42 faces towards the cylinder head and the side labeled 43 faces towards the air intake manifold. It is to be noticed that the distance of beading from the periphery of apertures 32 on face 42 is more than that of the distance of the beading from the periphery of aperture on face 43. In the same figure, the side view of the sealing material is shown. The offset between the location of the headings 45 and 46 is clearly visible. It is clear from the above description and the diagrams that the beading 46 belongs to the cylinder side and the beading 45 belongs to the beading on the air intake manifold side. The beading on the cylinder head side of the sealing material is denoted by 31/46 and 46 denotes the beading on the air intake manifold side of the sealing material. Figure 5 shows the sealing material 24 of the side facing the air intake manifold with the beading 41 and the beading 31. The face 43 belongs to the air intake manifold side.

We claim:

1. An internal combustion engine (13) comprising :an air intake manifold (22); a cylinder head (17) wherein the said cylinder head (17) is joined to the said air intake manifold (22); a sealing material (24) wherein the said sealing material (24) resides between the said air intake manifold (22) and the said cylinder head (17); the said sealing material (24) comprises of atleast one aperture (32) and atleast one beading (45,46) on both of its faces such that the said beading (45,46) surrounds the said aperture (32);
wherein the said beading (46) of the said sealing material (24) is placed at a larger pre-determined distance on the cylinder head side than the distance of the beading (45) on the said sealing material (24) on the air intake manifold side.

The internal combustion engine as claimed in Claim 1 wherein the beading (45, 46) distance from the aperture (32) of the sealing material (24) being determined by aperture sizes (25, 33) of cylinder head (17) and air intake manifold (22).

The internal combustion engine as claimed in Claim 1 wherein the beading (45, 46) is preferably made of silicone rubber.

The internal combustion engine as claimed in Claim 1 wherein the said sealing material (24) is preferably made of high temperature resistant material.