JP6395417B2 - Cylinder head gasket - Google Patents

Description

  The present invention relates to a cylinder head gasket constituting an internal combustion engine.

  2. Description of the Related Art Conventionally, a flow path such as a cooling flow path is provided inside an internal combustion engine in order to quickly perform cooling by circulating a coolant through the internal combustion engine. With regard to this cooling flow path, a specific arrangement and shape of the cooling flow path is disclosed in, for example, Patent Document 1 in order to efficiently cool a portion where the temperature easily rises in the internal combustion engine. Yes. In such Patent Document 1, a water jacket that is a cooling flow path provided in a cylinder block has a tip that protrudes so as to drive the coolant toward a place where the distance between two adjacent combustion chambers becomes the shortest. A portion having an opening shape is provided.

JP 2002-309996 A

An object of the present invention is to flow cooling water to a location closest to the cylinder to further promote cooling of the combustion chamber .

  In order to achieve such an object, the present invention takes the following measures.

That is, a cylinder head gasket according to the present invention is disposed between a cylinder block and a cylinder head of an internal combustion engine having a plurality of cylinders, and includes a bore of the cylinder block and a ceiling portion of a combustion chamber of the cylinder head. A plurality of combustion chamber holes interposed between and a cooling hole communicating with a cooling passage for flowing a cooling liquid provided in the cylinder block and the cylinder head, the cooling hole comprising : It has an opening for cooling the combustion chamber that is positioned between two adjacent combustion chamber holes and has a substantially V shape in plan view , and is an edge closer to the combustion chamber hole in the opening for cooling the combustion chamber The driving edge is closer to the combustion chamber hole than the opening of the cooling flow path of the cylinder block overlapping the opening for cooling the combustion chamber in plan view, and the driving edge is cooled in the combustion chamber in plan view. Is substantially equal to or slightly closer to the edge of the opening of the cooling flow path of the cylinder head that overlaps the opening for cooling, and is further away from the combustion chamber hole in the opening for cooling the combustion chamber. A protrusion is formed on the edge to project the material along the shape of the driving edge, the protrusion covers the opening of the cooling passage of the cylinder block in plan view, and the protrusion is in plan view. It covers the opening of the cooling flow path of the cylinder head .

  If it is such, since the flow of the coolant flowing through the opening for cooling the combustion chamber is guided in the direction toward the combustion chamber hole by the protrusion, cooling of the combustion chamber is effectively promoted. As a result, an improvement in anti-knocking performance is expected, and as a result, an increase in thermomechanical conversion efficiency that suppresses retarding of the ignition timing to prevent knocking, that is, an increase in fuel consumption can be brought about. Further, by improving the cooling performance of the combustion chamber, the shape of the combustion chamber, particularly the cylinder head in plan view, can be made closer to a perfect circle so that friction can be reduced.

  ADVANTAGE OF THE INVENTION According to this invention, the structure of the internal combustion engine which can improve cooling performance effectively can be provided.

1 is a schematic external view according to an embodiment of the present invention. Structure explanatory drawing which concerns on the same embodiment. The A section enlarged view which concerns on FIG. Explanatory drawing which concerns on the prior art of this invention.

  An embodiment of the present invention will be described with reference to the drawings. In FIG. 1, the outline | summary of the internal combustion engine for vehicles which is a structure in this embodiment is shown. The internal combustion engine of the present embodiment is, for example, a port injection type four-stroke spark ignition engine, and includes three cylinders 1a, 1b, and 1c. These cylinders 1a, 1b and 1c are arranged in series. In this internal combustion engine, the cylinder block 2 constituting the cylinder bore 2a, the plate-like gasket 3 and the cylinder head 4 constituting the combustion chamber ceiling 4a are formed from the lower side so as to constitute the cylinders 1a, 1b and 1c. It is firmly fixed by welding and fastening in the state of being stacked in this order. In order to avoid an excessive temperature rise due to combustion of each cylinder 1a, 1b, 1c, the internal combustion engine has a water jacket which is a cooling flow path for flowing a coolant, i.e., a coolant, over the cylinder block 2, gasket 3 and cylinder head 4. 5 is formed.

  The gasket 3 includes a welded portion 31 that is welded to the cylinder block 2 and the cylinder head 4 by welding, and cooling that constitutes the cylinders 1a, 1b, and 1c, that is, the combustion chamber holes 32 and the water jacket 5 for constituting the combustion chamber. And an opening 30 including a use hole 33. In other words, the combustion chamber hole 32 is interposed between the cylinder bore 2 a formed in the cylinder block 2 and the ceiling portion 4 a of the combustion chamber of the cylinder head 4. The water jacket 5 is configured with both the cylinder block 2 and the cylinder head 4, and communicates with the water jacket 5 at the cooling hole 33.

  FIG. 2 is a configuration explanatory view showing the cylinder block 2 by a broken line, the outer shape of the cylinder head 4 by a two-dot chain line, and a welded portion 31 and an opening 30 of the gasket 3.

In the cylinder block 2, a large opening is provided in order to allow the cooling water to flow widely around the cylinders 1 a, 1 b, and 1 c, and in the cylinder head 4, the cylinder block 4 is located in a position close to the two adjacent combustion chamber holes 32. The driving portion 40 having a triangular shape in plan view is positioned. The drive-in portion 40 is an opening having an area larger in plan view than the cooling hole 33 of the cylinder head gasket 3 overlapping in plan view.

  Therefore, the cylinder head gasket as the gasket 3 according to the present embodiment is interposed between the cylinder block 2 and the cylinder head 4 and has a combustion chamber hole 32 and a cooling hole 33 constituting a combustion chamber. The cooling hole 33 has a combustion chamber cooling port 34 that is an opening for cooling the combustion chamber located between the two adjacent combustion chamber holes 32, and the combustion chamber cooling port 34 includes two adjacent combustion chamber cooling ports 34. It is characterized by having a projecting portion 35 provided by projecting the material so that the coolant flows toward the place where the combustion chamber hole 32 is closest.

  Hereinafter, the configuration of the combustion chamber cooling port 34 will be described.

  As shown in FIG. 3, the combustion chamber cooling port 34 includes a driving edge 36 formed by denting the shape to a level approximately equal to the shape of the driving portion 40 in plan view, and a material along the shape of the driving edge 36. It has a generally arrowhead shape in a plan view in which a protruding portion 35 formed by protruding is formed. In other words, the combustion chamber cooling port 34 has a substantially V shape in plan view. Here, in the present embodiment, the shape of the driving edge 36 is substantially the same as that of the driving portion 40 in a plan view. It may be formed in a recess. In other words, the driving edge 36 may not protrude into the water jacket 5 even if there is a dimensional error.

  By adopting such a shape, the cylinder head so that the cooling water flowing from the cylinder block 2 side through the driving portion 40 on the cylinder head 4 side of the water jacket 5 is inclined toward the driving edge 36 by hitting the protruding portion 35. 4 will flow through. That is, the cooling water flows so as to concentrate in the portion of the driving edge 36 closest to the cylinders 1a, 1b, and 1c, so that the cooling of the cylinders 1a, 1b, and 1c, that is, the combustion chamber is further promoted.

  In contrast, FIG. 4 illustrates the structure of the conventional gasket 3. In the figure, components corresponding to the components of the present embodiment are denoted by the same reference numerals, and description thereof is omitted. In such a gasket 3, the cooling hole 33 overlapping the driving portion 40 forms a substantially circular shape at a position away from the combustion chamber hole 32, so that the cooling water passing through the cooling hole 33 is driven in. In the portion 40, the flow is preferentially performed on the side farther from the wider cylinders 1a, 1b, and 1c, and the effect of sufficiently cooling the cylinders 1a, 1b, and 1c cannot be obtained.

  With the configuration as described above, in the gasket 3 which is the cylinder head gasket according to the present embodiment, the coolant flowing through the combustion chamber cooling port 34 is guided in the direction toward the combustion chamber hole 32 by the protruding portion 35. Therefore, cooling of the combustion chamber, that is, the cylinders 1a, 1b, and 1c is effectively promoted. As a result, an improvement in anti-knocking performance is expected, and as a result, an increase in thermomechanical efficiency, that is, an increase in fuel consumption can be brought about by suppressing retarding of the ignition timing to prevent knocking.

  In particular, according to the present embodiment, by improving the cooling performance, the shape of the cylinder bores 2a of the cylinders 1a, 1b, and 1c, particularly the cylinder block 2 is set to a shape closer to a perfect circle to reduce friction. Since knocking resistance can be ensured even if it is damped, it contributes to further improvement in fuel efficiency that has led to a reduction in mechanical loss.

  Although the embodiment of the present invention has been described above, the specific configuration of each unit is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

  For example, in the above-described embodiment, the aspect in which the present invention is applied to an internal combustion engine having three cylinders is disclosed, but the number of cylinders is not limited. In addition, the specific mode such as the specific flow path shape of the water jacket and the material and thickness dimensions of the cylinder head gasket are not limited to those of the above embodiment, and various modes including the existing ones are available. Can be applied.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  The present invention can be used as a cylinder head gasket used in an internal combustion engine.

2 ... Cylinder block 3 ... Gasket 32 ... Combustion chamber hole 33 ... Cooling hole 34 ... Combustion chamber cooling opening (combustion chamber cooling port)
35 ... Projection 4 ... Cylinder head 5 ... Cooling channel (water jacket)

Claims (1)

A cylinder head gasket disposed between a cylinder block and a cylinder head of an internal combustion engine having a plurality of cylinders ,
A plurality of combustion chamber holes interposed between a bore of the cylinder block and a ceiling portion of the combustion chamber of the cylinder head, and a cooling flow path for flowing a coolant provided in the cylinder block and the cylinder head ; and a cooling hole,
The cooling hole has an opening for cooling the combustion chamber which is located between two adjacent combustion chamber holes and has a substantially V shape in plan view ;
The driving edge, which is the edge closer to the combustion chamber hole in the combustion chamber cooling opening , is located closer to the combustion chamber hole than the opening of the cooling flow path of the cylinder block overlapping the combustion chamber cooling opening in plan view. The approach edge is substantially the same as or slightly closer to the edge of the opening of the cooling flow path of the cylinder head that overlaps the opening for cooling the combustion chamber in plan view. ,
In the opening for cooling the combustion chamber, at the edge farther from the combustion chamber hole, a protruding portion is formed by protruding the material along the shape of the driving edge, and the protruding portion is a cooling of the cylinder block in plan view. A cylinder head gasket that covers the opening of the flow path and has the protruding portion that covers the opening of the cooling flow path of the cylinder head in plan view .

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