FR3059048B1 - INTERNAL COMBUSTION ENGINE HAVING NON-STRUCTURAL DISTRIBUTION CASE - Google Patents

Abstract

The invention relates to an internal combustion engine (20) comprising a cylinder block (7), a chain distribution drive system (3) located in a sealed chamber (19) enclosed between an outer face (18) of the cylinder block (7) and a timing cover (11), - the timing cover (11) being fixed to the cylinder block (7) in an oil-tight manner; - the combustion engine (20) comprising at least one engine support (8), characterized in that - the engine support (8) is fixed to the cylinder block (7) by a lug (12); - the timing cover (11) has an opening (13), laterally limited by an edge (21); - The opening (13) of the timing cover (11) allows the tab (12) to pass through the timing cover (11) to transmit the forces of the engine support (8) directly to the cylinder block (7).

Description

Internal combustion engine having a non-structural distribution casing

Technical Field The invention relates to an internal combustion engine of a motor vehicle whose distribution drive system comprises a chain.

State of the art

The distribution drive system comprised of at least one crank sprocket, a camshaft, a chain, a chain guide, a chain tensioner are enclosed in a lubricated environment. The drive of the distribution of an internal combustion engine by a chain requires a good lubrication thereof.

An internal combustion engine of a motor vehicle is suspended from the chassis of the vehicle by at least two attachment points located on either side of the engine. The positions of the fastening points on the engine, also called engine support or SMO, are optimized to minimize the transfer of engine stresses to the chassis of the vehicle. An engine support can thus be located in the drive zone of the distribution and more particularly in an area requiring to receive a timing case to ensure good lubrication of the distribution system.

When the engine support is positioned in an area intended to receive a timing case, it has already been proposed to arrange the engine support directly on the timing case.

One of the disadvantages of positioning an engine support on the timing case is that the timing case requires a suitable design to ensure the transfer of the engine forces to the chassis of the vehicle with good rigidity and to ensure a good seal of the timing case with cylinder block. The sizing of the timing case comprising an engine support generates a relatively high mass and a relatively large number of assembly points. The seal between the timing case comprising a motor support requires the use of a seal capable of providing a good seal and good rigidity. Seals offering rigidity and tightness generally do not allow easy disassembly of the timing case. Often the replacement of the gasket is necessary during dismantling and reassembly of the timing case. Summary of the invention

According to a first aspect, the inventors propose an internal combustion engine of a motor vehicle which comprises a cylinder block, a crankshaft, a valve control system comprising at least one camshaft and at least one drive chain of the shaft. cam follower by said crankshaft, said chain being located in a sealed chamber enclosed between an outer face of the cylinder block and a timing case, the timing case being secured to the cylinder block in an oil-tight manner; the combustion engine comprising at least one engine support; characterized in that the motor support is fixed to the cylinder block by a tab; the distribution casing has an opening, limited laterally by an edge; the opening of the timing case allows the tab to pass through the timing case to transmit the forces of the engine support directly to the cylinder block. The invention allows the decoupling of the sealing function of the necessary structural mechanical functions when the engine support is positioned in the area of the distribution case. The invention makes it possible to have a distribution casing whose only sealing function must be taken into account during its development. The invention makes it possible to simplify the sealed assembly of the distribution casing to the cylinder block because it allows the use of less expensive sealing means and easier to put in place. The invention allows during assembly, the use of fewer fasteners and a lower assembly accuracy. The invention guarantees excellent rigidity of the engine support because it is directly attached to the cylinder block. The invention makes it possible to have a distribution casing whose only sealing function allows the use of materials which make it possible to minimize the mass of the distribution casing and the overall cost of the function.

The cylinder block is also called a cylinder block and is part of the engine block.

The cylinder block comprises at least one cylinder, advantageously, it comprises a cylinder row.

Preferably, sealing means are interposed between the edge of the opening of the timing case and the lug.

The sealing means make it possible to guarantee a good oil seal at the edges of the opening of the distribution casing and of the lug allowing a mechanical connection between the engine support and the cylinder block.

Preferably, the sealing means are formed by a seal which is interposed between the edge of the opening of the distribution casing and the cylinder block so as to form a sealed connection.

Preferably, the seal is mounted in a groove located on the surface of the tab.

The presence of a groove on the surface of the tab allows easy positioning of the seal during assembly of the timing block to the cylinder block.

Preferably, the seal is an O-ring. The use of an O-ring makes it easy and inexpensive to replace it when disassembling and reassembling the timing case for a maintenance operation for example.

Preferably, the seal between the cylinder block and the distribution casing is formed by a peripheral O-ring interposed between the distribution casing and the cylinder block. The use of a peripheral O-ring makes it easy and inexpensive to replace it when disassembling and reassembling the timing case for a maintenance operation for example. The use of an O-ring for sealing the timing case is made possible because the assembly only provides the sealing function by decoupling the structural mechanical functions necessary when the SMO is positioned on the timing case.

Preferably, the O-ring is mounted in a groove located on the surface of the timing case.

The presence of a groove on the surface of the timing case allows easy positioning of the seal when assembling the timing block to the cylinder block.

Preferably, the seal between the cylinder block and the distribution casing is formed by a fluidized seal interposed between the distribution casing and the cylinder block.

Preferably, the distribution casing is made of plastic. The use of a polymer type plastic material allows the use of manufacturing processes such as injection molding to reduce manufacturing costs. It also greatly reduces the mass of the timing case. For example, the injection molding of the distribution casing makes it possible to produce a groove on its surface intended to receive an O-ring, for example.

Preferably, the distribution casing is made of polyhexamethylene adipamide (PA66). The use of Polyhexamethylene adipamide (PA66) is standard for automobile parts manufacturers.

Preferably, the distribution case is made of aluminum.

Preferably, the distribution case is made of pressed steel sheet.

Brief description of the figures

These aspects as well as other aspects of the invention will be clarified in the detailed description of particular embodiments of the invention, reference being made to the drawings of the figures, in which: the Figurel shows an exploded close-up view of an embodiment of the internal combustion engine of a motor vehicle, the timing case and the engine support according to the invention, the internal combustion engine of a motor vehicle and the distribution casing has sections indicated by the hatched areas; FIG. 2 shows an exploded view of an embodiment of the internal combustion engine of a motor vehicle, of the timing case and of the engine support according to the invention, the internal combustion engine of a motor vehicle and the timing case. has sections indicated by the hatched areas; - Figure 3 shows a perspective view of an outer face of the cylinder block comprising the drive system of the distribution and the engine support according to the invention.

The drawings of the figures are not to scale. Generally, similar elements are denoted by similar references in the figures. The presence of reference numbers in the drawings can not be considered as limiting, even when these numbers are indicated in the claims.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS OF THE INVENTION

FIG. 1 shows an exemplary embodiment of a motor vehicle internal combustion engine 20 and a distribution casing 11 according to the invention. The engine 20 comprises at least one cylinder, a movable hitch and a valve control system driven by a chain 3 via a crankshaft. Driven camshaft by timing chain requires lubrication of the chain. The distribution drive system consisting of crankshaft pinions 1 and camshaft 2, chain 3, chain guides 4 and chain tensioner 5 are confined in a sealed chamber 19 delimited by a crankcase. 11 and an outer face 18 of the cylinder block 7. The cylinder block 7 comprises a lug 12 on which is fixed a motor support 8. The lug 12 and the engine support 8 are arranged on the outer face 18 of the cylinder block 7 provided to receive the timing case 11. The distribution case 11 has an opening 13 through which the tab 12 and the engine support 8 can pass through the distribution case 11. The opening 13 in the distribution case 11 makes it possible to have a motor support 8 at the timing case 11 and transmit the forces of the engine support 8 to the cylinder block 7 via the tab 12. The sealing of the timing case 11 at the level of the support mote ur 8 is provided at the lug 12, with sealing means interposed between the lug 12 and the edge 21 of the opening 13. The sealing means at the lug 12 are for example a seal 14 , preferably the seal 14 is an O-ring.

In variant not shown, the gasket 14 is a gasket that is to say a seal obtained by depositing silicone at the interface of the parts to be assembled, which hardens after tightening ensuring a perfect seal.

Preferably, the seal 14 is mounted in a groove 15 located at the periphery of the tab 12. The tab 12 is for example of cylindrical shape. When assembling the timing case 11 to the cylinder block 7, the seal 14 is clamped between the edges 21 of the opening 13 and the tab 12 to ensure sealing.

The elements represented in dashed dots correspond to the distribution casing 11 in the closed position. In the closed position, the seal 14 is interposed between the edges 21 of the opening 13 of the distribution casing 11 and the lug 12 of the engine support 8.

FIG. 2 shows an exemplary embodiment of the motor vehicle internal combustion engine 20 and the distribution casing 11 according to the invention. The assembly between the timing case 11 and an outer face 18 of the cylinder block 7 forms an oil-tight chamber 19. The assembly of the distribution casing 11 to the cylinder block 7 is for example carried out by studs 10. The assembly of the distribution casing 11 on the outer face 18 of the cylinder block 7 forms a tight connection. The tightness of the assembly between the distribution case 11 and the outer face 18 of the cylinder block 7 is provided by a seal 16 preferably located at the periphery of the distribution case. The peripheral seal 16 is preferably an O-ring.

In variant not shown, the peripheral seal is a fluted joint.

The O-ring is mounted in a groove 17 located on the distribution casing 11 and preferably at the periphery of the distribution casing 11. The sealed chamber 19 formed between an outer face 18 of the cylinder block makes it possible to receive the drive system. the distribution of the motor 20. The sealed chamber 19 ensures good lubrication of the drive system of the distribution of the motor 20 and in particular of the chain 5. The groove 17 located on the timing case is for example made during the molding of it.

The elements represented in dashed dots correspond to the distribution casing 11 in the closed position. In the closed position, the seal 14 is interposed between the edges 21 of the opening 13 of the distribution case 11 and the lug 12 of the engine support 8. In the closed position, the seal 16 is clamped between the distribution case 11 and the face external cylinder block 18 to ensure the peripheral sealing of the timing case 11.The housing is made of a lightweight material. Since the engine support forces are transmitted directly to the cylinder block without passing through the timing case, the choice of material is extended. The distribution case 11 is for example injection molded. The distribution casing 11 is for example molded in polyhexamethylene adipamide (PA66) or in PA66GF30.

Alternatively, the distribution case 11 is for example aluminum, preferably with a thin wall or pressed steel sheet.

FIG. 3 shows an exemplary embodiment of the motor vehicle internal combustion engine 20 comprising a motor support 8 according to the invention. The distribution drive system composed of at least one crankshaft pinion 1, a camshaft 2, a chain 3, a chain guide 4, a chain tensioner 5 are located on an outer face 18 of the block cylinder 7. The engine support 8 is for example positioned on the same outer face 18 of the cylinder block 7 and comprises a lug 12 on which a groove 15 can receive a seal 14. When assembling the distribution case 11, the distribution drive system is then confined in a sealed chamber 19 to ensure good lubrication of the drive system of the distribution. The use of O-rings sealing is preferable when the timing case 11 is disassembled and reassembled for maintenance operations for example.

The main function of the distribution casing of the invention is a sealing function. The timing case allows good lubrication of the drive system of the motor 20 by chain 3 by ensuring containment of the oil inside the timing case 11 and watertightness to avoid contamination of the sealed chamber 19 with water which can affect the lubrication of the mechanical elements. The invention can also be described such that the decoupling of the sealing function of the structuring mechanical functions is made possible thanks to the opening 13 located in the distribution casing 11, by the tab 12 allowing the transfer of the forces of the motor support 8 to the cylinder block 7 and by the sealing means ensuring the tightness of the sealed chamber 19. This new architecture allows the use of lighter and less expensive materials for the manufacture of the timing case 11. The costs and the mass associated with the engine support function 8 on the same face of the cylinder block as the drive system of the distribution are thus reduced.

The present invention has been described in relation to specific embodiments, which have a purely illustrative value and should not be considered as limiting. In general, the present invention is not limited to the examples illustrated and / or described above. The use of the verbs "to understand", "to include", "to include", or any other variant, as well as their conjugations, can in no way exclude the presence of elements other than those mentioned. The use of the indefinite article "a", "an", or the definite article "the", "the" or "Γ", to introduce an element does not exclude the presence of a plurality of these elements. The reference numerals in the claims do not limit their scope.

In summary, the invention can also be described as follows. The invention relates to an internal combustion engine 20 which comprises a cylinder block 7, a chain distribution drive system 3 located in a sealed chamber 19 enclosed between an outer face 18 of the cylinder block 7 and a distribution casing 11, the distribution case 11 being fixed to the cylinder block 7 in an oil-tight manner; the combustion engine 20 comprising at least one engine support 8, characterized in that the engine support 8 is fixed to the cylinder block 7 by a lug 12; the distribution casing 11 has an opening 13, limited laterally by an edge 21; the opening 13 of the distribution casing 11 allows the lug 12 to pass through the distribution casing 11 to transmit the forces of the motor support 8 directly to the cylinder block 7.

Claims (9)

A motor vehicle internal combustion engine (20) having a cylinder block (7), a crankshaft (1), a valve control system comprising at least one camshaft (2) and at least one chain (3). ) driving the camshaft by said crankshaft (1), said chain (3) being located in a sealed chamber (19) enclosed between an outer face (18) of the cylinder block (7) and a timing case (11), the distribution casing (11) being made of plastic material and being fixed to the biocylinder (7) in an oil-tight manner; the combustion engine (20) having at least one engine support (8); characterized in that the motor support (8) is fixed to the cylinder block (7) by a tab (12); the distribution casing (11) has an opening (13) limited laterally by an edge (21); the opening (13) of the distribution casing (11) allows the lug (12) to pass through the distribution casing (11) in order to transmit the forces of the motor support (8) directly to the cylinder block (7). 2. Motor (20) according to the preceding claim, characterized in that sealing means are interposed between the edge (21) of the opening (13) of the timing case (11) and the lug (12). 3. Motor (20) according to any one of the preceding claims, characterized in that the sealing means are formed by a seal (14) which is interposed between the edge (21) of the opening (13) of the housing of distribution (11) and the cylinder block (7) so as to form a sealed connection. 4. Motor (20) according to the preceding claim, characterized in that the seal (14) is mounted in a groove (15) located on the surface of the lug (12). 5. Motor (20) according to any one of claims 3 or 4, characterized in that the seal (14) is an O-ring. 6. Motor (20) according to any one of the preceding claims, characterized in that the seal between the cylinder block (7) and the distribution casing (11) is formed by a seal (16) peripheral ring interposed between the timing case (11) and cylinder block (7). 7. Motor (20) according to the preceding claim, characterized in that the seal (16) peripheral ring is mounted in a groove (17) located on the surface of the timing case (11). 8. Motor (20) according to any one of claims 1 to 5, characterized in that the seal between the cylinder block (7) and the distribution casing (11) is formed by a seal (16) fiue interposed between the timing case (11) and the cylinder block (7). 9. Motor (20) according to any one of the preceding claims, characterized in that the distribution casing (11) is made of polyhexamethylene adipamide (PA66).