JP2012149581A - Internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal combustion engine that effectively improves fuel consumption by improving knocking resistance.SOLUTION: The internal combustion engine includes a pair of ribs, i.e., a third rib 27 and a fourth rib 29 projected from the upper wall 13 of a water chamber 17 of a cylinder head 1, facing each other in the moving direction of cooling water W and disposed in front of and behind a combustion chamber 5. The third rib 27 and the fourth rib 29 have recesses 37, 41 formed by denting parts close to the center of the combustion chamber 5 on projection ends 35, 39.

Description

  The present invention relates to an internal combustion engine including a cylinder head configured so that a cooling water flow flows in a predetermined direction.

  2. Description of the Related Art Conventionally, various internal combustion engines have been proposed that include a cylinder head in which a plurality of cylinders are integrally formed so that a cooling water flow flows in a predetermined direction (see, for example, Patent Document 1). In the device disclosed in the patent document, a flow of cooling water is promoted by providing a control rib formed by protruding a wall surface in a water chamber through which cooling water flows.

  However, in the conventional flow of cooling water in the water chamber of an internal combustion engine, including those described in the above-mentioned patent documents, the temperature of the combustion chamber can be reduced overall, but the ignition plug and the ignition plug If the temperature at the center of the combustion chamber in which the is placed becomes high, the possibility of knocking also increases. Until now, the compression ratio has been set in consideration of the possibility of knocking that occurs in this way, so the compression ratio could not be increased.

JP 2003-286896 A

  The present invention focuses on reducing the temperature in the vicinity of the center of the combustion chamber as described above, and it is possible to improve the fuel efficiency effectively by improving the knock resistance and improving the compression ratio. It aims at providing the internal combustion engine which can be performed.

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

  That is, the internal combustion engine according to the present invention is an internal combustion engine including a cylinder head that flows in the water chamber when the cooling water moves in the front-rear direction, and the ribs that form a pair protruding from the wall of the water chamber are provided with the cooling water. The ribs are provided in front of and behind the combustion chamber so as to face each other in the moving direction, and the rib has a recess formed by recessing a portion of the protruding edge adjacent to the center of the combustion chamber.

  In such a case, by increasing the flow rate of the cooling water at the center of the combustion chamber, the temperature near the center of the combustion chamber and the temperature of the spark plug attached to the center of the fuel chamber can be effectively reduced. it can. Thereby, the compression ratio can be increased by improving the knock resistance, and as a result, the fuel consumption of the internal combustion engine can be effectively improved.

  Further, in order to further promote the flow of the cooling water near the center of the combustion chamber, it is preferable that the rib is curved so as to approach the center of the combustion chamber.

  According to the present invention, the compression ratio can be increased by improving the knock resistance, and consequently the fuel consumption of the internal combustion engine can be effectively improved.

The center front sectional view of the cylinder head concerning one embodiment of the present invention. Structure explanatory drawing which concerns on the same embodiment. FIG. 3 is an end view taken along the line II in FIG. 2. II-II line end view concerning FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In FIGS. 1 and 2, the behavior of the cooling water W flowing is schematically shown by thick arrows.

  As shown in FIGS. 1 and 2, the cylinder head 1 of the internal combustion engine according to the present embodiment is applied to an internal combustion engine that is an in-line two-cylinder engine, for example. Is provided with an oil jacket 3. A spark plug mounting hole 7 is formed at the center of each combustion chamber 5 at the bottom of the cylinder head 1 so as to face the combustion chamber 5 formed on the lower surface thereof. A pair of exhaust valve ports 9 is formed in one of the spark plug mounting holes 7, and an intake valve port 11 is formed in the other. The exhaust valve port 9 is connected to an exhaust port (not shown) formed in the lower part of the cylinder head 1 so as to open one side surface thereof. The intake valve port 11 is also connected to an intake port (not shown) formed in the lower part of the cylinder head 1 so as to open to the other side surface. In the lower part of the cylinder head 1, a water chamber 17 is formed from the oil jacket 3 through the upper wall 13 and from the upper part of the combustion chamber 5 through the lower wall 15. The cooling water W can flow in the water chamber 17 while moving in the front-rear direction, so that the cooling water W can cool the upper portion of the combustion chamber 5 and the oil jacket 3.

  This water chamber 17 has four ribs 23, 25, 27, 29 provided so as to project from the cooling water inlet 19, the cooling water outlet 21, and the upper wall 13, that is, first from the front side. The rib 23, the second rib 25, the third rib 27, and the fourth rib 29 are provided. In the present embodiment, for convenience of explanation, the direction from the cooling water inlet 19 to which the cooling water W moves to the cooling water outlet 21 will be referred to as the front-rear direction, the cooling water inlet 19 side being the front side, The outlet 21 side is described as the rear side.

  As shown in FIG. 2, the first rib 23 is provided in the vicinity of the cooling water inlet 19 so as to extend in an oblique direction, and is inclined so as to gradually decrease as the protruding end 31 protrudes backward. A protruding end 33 is formed.

  As shown in FIG. 2, the second rib 25 is provided to be curved so as to be close to the center of the front combustion chamber 5. The second rib 25 is set to have a shorter length than the other three ribs.

  Therefore, the internal combustion engine according to the present embodiment causes the pair of ribs that protrude from the upper wall 13 that is the wall of the water chamber 17 of the cylinder head 1, that is, the third rib 27 and the fourth rib 29 to move in the moving direction of the cooling water W. The third rib 27 and the fourth rib 29 are provided in front of and behind the combustion chamber 5 so as to face each other, and have recess portions 37 and 41 formed by recessing portions of the projecting ends 35 and 39 close to the center of the combustion chamber 5. It is characterized by that. Hereinafter, a specific configuration of the third rib 27 and the fourth rib 29 which are pairs of ribs according to the present invention will be described.

  As shown in FIGS. 2 to 4, the third rib 27 is formed to extend in the direction perpendicular to the front-rear direction in front of the center of the rear combustion chamber 5, that is, the spark plug mounting hole 7. Further, an intermediate portion of the third rib 27 is formed so as to be curved toward the center of the combustion chamber 5. A recessed portion 37 having a low protruding height is formed at a position closest to the spark plug mounting hole 7 at the protruding end 35 from which the third rib 27 protrudes.

  As shown in FIGS. 2 to 4, the fourth rib 29 is formed to extend in the direction orthogonal to the front-rear direction at the center of the rear combustion chamber 5, that is, behind the spark plug mounting hole 7. Similarly to the third rib 27, the middle portion of the fourth rib 29 is formed so as to be curved toward the center of the combustion chamber 5. A recessed portion 41 having a low protruding height is formed at a position closest to the spark plug mounting hole 7 at the protruding end 39 from which the fourth rib 29 protrudes.

  Subsequently, the flow of the cooling water W caused by the formation of the four ribs 23, 25, 27, 29 described above will be described with reference to FIGS. 1 and 2, but the flow is of course not shown. Needless to say, the flow is in a state where an exhaust valve or the like is attached.

  First, the cooling water W introduced from the cooling water introduction port 19 is appropriately dispersed also in the exhaust valve port 9 and the intake valve port 11 while flowing vigorously toward the spark plug mounting hole 7 by the first rib 23. The cooling water W that has passed through the vicinity of the spark plug mounting hole 7 is temporarily blocked by the second rib 25, so that the cooling water W between the outer surface of the spark plug mounting hole 7 and the central portion of the combustion chamber 5 and the second rib 25. By convection so that the cooling water W swirls vigorously, the spark plug and the center of the combustion chamber 5 are quickly cooled.

  Then, the cooling water W that has passed over the combustion chamber 5 on the front side is concentrated at a portion of the third rib 27 that is curved backward by the third rib 27. And since the hollow part 37 is provided in the location curved backward, the cooling water W flows from the hollow part 37 toward the rear spark plug mounting hole 7 vigorously, and the outer surface of the spark plug mounting hole 7 And between the center part of the combustion chamber 5 of the rear side, and the 3rd rib 27, the cooling water W will again convect so that it may swirl vigorously. Thereby, the spark plug and the center of the combustion chamber 5 are quickly cooled.

  Further, the cooling water W that has passed through the third rib passes through the spark plug mounting hole 7 and is then temporarily blocked by the fourth rib 29. The cooling water W also convects vigorously between the outer surface of the spark plug mounting hole 7 and the center of the combustion chamber 5 and the fourth rib 29. Thereafter, the cooling water W is promptly flowed from the recess formed in the fourth rib 29 toward the cooling water discharge port 21, whereby the center portion of the rear combustion chamber 5 and the spark plug mounting hole 7 and the fourth Water flow between the ribs 29 is further promoted. As a result, the spark plug mounting hole 7 and the center of the combustion chamber 5 are rapidly cooled here.

  By adopting the above-described configuration, the internal combustion engine having the cylinder head 1 according to the present embodiment is such that the cooling water W that has flowed through the water chamber 17 once is preferably concentrated at the center of the combustion chamber 5. Therefore, the flow rate of the cooling water W flowing through the center of the combustion chamber 5 can be effectively increased. Thereby, in particular, the temperature near the center of the combustion chamber 5 and the temperature of the spark plug attached to the center of the fuel chamber 5 can be effectively reduced. With such a configuration, the compression ratio can be set high by improving the knock resistance of the internal combustion engine. As a result, it contributes to the realization of an internal combustion engine that effectively improves fuel consumption.

  Further, in order to further promote the flow of the cooling water W near the center of the combustion chamber 5, the third rib 27 and the fourth rib 29 are brought close to the center of the combustion chamber 5 in the present embodiment. The shape is curved like this. Thus, the cooling effect can be further enhanced by further promoting the flow of the cooling water W in the central portion of the combustion chamber 5, that is, in the vicinity of the spark plug.

  In addition, in the present embodiment, the four ribs 23, 25, 27, and 29 are provided on the upper wall 13 that covers the oil jacket 3, so that not only the ignition plug and the combustion chamber 5 but also the oil jacket 3 is cooled. It has become more useful. That is, the heat of the lubricating oil in the oil jacket 3 can be actively released, and the increase in the lubricating oil temperature can be effectively prevented. Furthermore, in the present embodiment, by forming these four ribs 23, 25, 27, 29, the rigidity of the cylinder head 1 itself is effectively improved.

  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, although the aspect which provided the rib in the upper wall was disclosed in the said embodiment, of course, what provided in the lower wall and what provided the rib in both the upper wall and the lower wall may be sufficient. In the above embodiment, a two-cylinder internal combustion engine in which a water chamber is disposed above the combustion chamber is disclosed. For example, an internal combustion engine in which the combustion chamber and the water chamber are disposed in a horizontal direction or an inclined direction, or more than two cylinders. It may be a multi-cylinder internal combustion engine. Further, specific modes such as the specific shape of the ribs, the depth of the recesses, and the number of the recesses are not limited to those of the above embodiment, and various modes including the existing ones can be applied. it can.

  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 an internal combustion engine having a cylinder head configured such that a cooling water flow flows in a predetermined direction.

DESCRIPTION OF SYMBOLS 1 ... Cylinder head 5 ... Combustion chamber 13 ... Wall (upper wall)
17 ... Water chamber 27 ... Rib (third rib)
29 ... rib (fourth rib)
37, 41 ... depression 35, 39 ... protruding end W ... cooling water

Claims (2)

An internal combustion engine comprising a cylinder head that flows in a water chamber when cooling water moves in the front-rear direction,
A pair of ribs protruding from the wall of the water chamber are provided in front of and behind the combustion chamber so as to face the moving direction of the cooling water,
The internal combustion engine, wherein the rib has a recess formed by recessing a portion of the protruding edge adjacent to the center of the combustion chamber. The internal combustion engine according to claim 1, wherein the rib is curved so as to approach the center of the combustion chamber.

Images