JP2946131B2 - Cylinder head of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder head for an internal combustion engine.

[0002]

2. Description of the Related Art In a cylinder head which is separate from a block, as shown in FIG. 5, a plurality of head bolts 101, 1 are inserted through the cylinder head vertically.
At 02, it is tightened and fixed. These head bolts usually consist of six bolts and are arranged so as to surround the periphery of the cylinder 103 so that the circumference of the cylinder 103 of the gasket provided between the cylinder head and the cylinder head seat surface of the cylinder block is completely formed. I try to make them adhere. At this time, in the portion of the push rod hole 104 for the intake / exhaust valve provided outside the cylinder 103, the head bolt 101 is connected to the push rod hole 10
4 and closer to the center.
The auxiliary bolt 105 is inserted into the outside of the housing to complete the sealing at this portion.

[0003]

As described above, conventionally, a head bolt is arranged in a push rod hole portion, and an auxiliary bolt is provided outside the push rod hole, so that a head seat in this portion is provided. The surface seal is reinforced. For that purpose, it is necessary to provide space for inserting the head bolts on both the inside and outside of the push rod hole. However, recently, it has become difficult to take such space due to the light and compact size of the engine. However, there was a disadvantage that the sealing was insufficient. In particular, recent engines tend to have higher in-cylinder pressure due to higher output, and sealing problems are severe. An object of the present invention is to realize a cylinder head structure capable of improving the sealing performance of the cylinder head seat surface even when the head bolt is arranged only outside the push rod portion as described above.

[0004]

In order to solve the above-mentioned problems, according to the present invention, a vertical rib 5 in a vertical direction corresponding to a head bolt located outside the push rod holes 2 and 3 of the cylinder head 1 is provided. Form. Further, horizontal ribs 6 and 7 for transmitting the tightening force of the head bolts from the head bolts on both sides of the head bolt to the vertical ribs 5 are provided.
It is integrally formed on at least one of the upper surface and the lower surface of the ceiling portion 8 of the cylinder head 1.

In the above description, it is conceivable that the horizontal ribs 6 and 7 are formed on the upper and lower surfaces of the ceiling 8 of the cylinder head 1. In this case, the lower ribs 6 are provided with cutouts 10 and 11 serving as air passages in the cooling water chamber 9 for passing air and water vapor mixed in the cooling water. Further, the lower rib 6 is arranged so as to limit the amount of cooling water passing through the upper portion of the exhaust port 12.
To avoid overcooling. This is because in engines with a turbocharger that collects and reuses the energy of exhaust gas, and in cogeneration type engines that use the heat, when the exhaust gas is supercooled and its temperature decreases, their efficiency decreases. For this reason, by appropriately arranging such ribs, it is possible to obtain an engine that is more efficient than conventional ones. On the other hand, the push rod holes 2 and 3 are also used as return holes for circulating the lubricating oil in the valve arm chamber 4 above the cylinder head 1 to the oil pan side. In order to make the lubricating oil flow smoothly into the push rod holes 2, 3, a notch 1
3 and 14 are formed. At this time, the amount of lubricating oil that drops from the push rod holes 2 and 3 is not the same on the intake valve side and the exhaust valve side. It is desirable to control the amount of lubricating oil by changing the size of the cutout portion in accordance with the required amount of oil so as to efficiently carry out the heating and prevent the occurrence of uneven temperature. This can be controlled according to the necessity of cooling and lubrication of the peripheral walls of the push rod holes 2 and 3.

[0006]

The tightening force of the head bolts outside the push rod holes 2 and 3 is transmitted to the center of the cylinder head 1 seating surface of the cylinder block via the vertical ribs 5, and further, the tightening force of the head bolts on both sides thereof. Is transmitted to the vertical ribs 5 through the horizontal ribs and similarly to the center side of the head seating surface.

[0007]

FIG. 2 shows an upper surface of the cylinder head 1. FIG. The cylinder head 1 of this embodiment is used for a three-cylinder engine, and has, in the center thereof, an exhaust valve insertion hole 18 and an intake valve insertion hole for each cylinder 17 along the arrangement direction of the cylinders 17 of the cylinder block. 19 are formed. Outside the valve insertion holes 18 and 19 in a direction perpendicular to the cylinder arrangement direction, a push rod hole 2 for an exhaust valve corresponding to the exhaust valve insertion hole 18 and an intake valve corresponding to the intake valve insertion hole 19 are formed. The push rod hole 3 is formed to penetrate the cylinder head 1 up and down. A mounting base 20 for the valve arm support member is mounted between the push rod holes 2 and 3 and the valve insertion holes 18 and 19 so as to protrude upward.

Further, a rib-shaped projecting wall 21 for mounting the valve arm chamber 4 of FIG. 1 around the valve insertion holes 18 and 19 and the push rod holes 2 and 3 and the mounting base 20 is provided.
It is formed integrally. Six head bolt holes 22, 23, 24 are provided for each cylinder 17 so as to penetrate from the upper surface to the lower surface of the projecting wall 21 and the cylinder head 1.
These cylinders 17 are formed in a state of being surrounded by a circle. However, adjacent cylinders 17, 17 ...
Are designed to share the two head bolt holes 23, 24.

As shown in FIGS. 1 and 4, a cooling water chamber 9 is formed inside the cylinder head 1, and inside the cooling water chamber 9, the inside of the head bolt holes outside the push rod holes 2 and 3 is formed. The vertical ribs 5 in the vertical direction are integrally formed so as to protrude from the wall of the cylinder head 1 toward the center. The upper end of the vertical rib 5 is continuous with the ceiling surrounding the upper part of the cooling water chamber 9, and the lower end is also continuous with the bottom wall.

Similarly, a push rod hole 2 is formed on the lower surface of the ceiling in the cooling water chamber 9 from the upper end of the vertical rib 5.
3 Head bolt hole 2 on both sides of outer head bolt hole 22
Two horizontal ribs 6, 6 extending toward 3, 23 are integrally formed. According to the present invention, the horizontal rib 6 has notches 10 and 11 at its tip, and
So as not to obstruct the flow of air and steam flowing along
It constitutes an air passage. In the cylinder head 1, an exhaust port 12 is provided which extends from the vicinity of the center of the lower surface of the cylinder head 1 to the side surface of the cylinder head 1 while being isolated from the cooling water chamber 9. Since the cooling water is provided above the exhaust port 12, the flow rate of the cooling water flowing above the exhaust port 12 is limited, thereby preventing the exhaust gas from being excessively cooled.

Next, on the upper surface of the ceiling portion 8 of the cylinder head 1, similarly, the head bolt holes 23, 23 on both sides of the push rod holes 2, 3 and the head bolt holes 22 on the outside are formed.
Upper horizontal ribs 7, 7 extending toward positions corresponding to the upper ends of the vertical ribs 5 are provided integrally.

The ends of the upper horizontal ribs 7, 7 on the side of the vertical ribs 5 are cut out 13 and 14, respectively, so that
The lubricating oil in the upper valve arm chamber 4 constitutes passages 29 and 30 for flowing toward the outer push rod holes 2 and 3. The cutout portion is made larger on the side flowing into the push rod hole 2 on the exhaust valve side than on the other side, so that a larger amount of lubricating oil flows relatively on the exhaust valve side than on the intake valve side. . Further, as described above, the cut-out upper horizontal ribs 7 and the lower horizontal ribs 6 have their ends overlapped with each other up and down.
The tightening force of the head bolts inserted into the head bolt holes 23 on both sides is effectively transmitted without interruption on the way. The cylinder head 1
Immediately above the vertical ribs 5 on the upper surface, another horizontal rib 31 is provided, which connects from the upper part of the outer head bolt hole 22 to the mounting base 20 of the valve arm support member.
The tightening force of the outer head bolt is also
, And also efficiently transmit the tightening force of the adjacent head bolts.

[0013]

As described above, according to the present invention, the longitudinal rib for transmitting the tightening force of the head bolt outside the push rod hole to the center of the cylinder head seating surface of the cylinder block is provided. Even in a compact cylinder head in which a head bolt cannot be provided on the inside, there is an effect that the sealing performance at the center of the seating surface can be improved. Not only that, the tightening force of the head bolts on both sides of the outer head bolt is transmitted to the vertical ribs by the horizontal ribs on the upper surface or the lower surface of the cylinder head ceiling or both, so that the in-cylinder pressure is high. Even in a high-power engine, sufficient sealing performance can be obtained. In addition, when a horizontal rib is provided on the lower surface of the ceiling, a part of the horizontal rib is cut out to provide an air passage, so that air or water vapor stays in the ceiling, and insufficient cooling of the upper portion of the point. Therefore, there is an effect that a problem such as the lubricating oil in the valve arm chamber being scorched can be prevented.

At this time, since the horizontal ribs are provided above the exhaust port, the flow rate of the cooling water flowing above the exhaust port is restricted, thereby lowering the efficiency of the exhaust turbine turbocharger due to the supercooling of the exhaust gas. Alternatively, a decrease in the efficiency of the cogeneration system can be prevented. On the other hand, when a horizontal rib is provided on the upper surface of the cylinder head ceiling, a cutout serving as a lubricating oil passage is provided in the horizontal rib, so that the circulation of the lubricating oil to the push rod hole is not hindered. There is a difference in size between the notch on the side that returns to the push rod hole on the side and the notch on the side that returns to the push rod hole on the intake valve side, and if necessary, lubrication that flows through both push rod holes. Controlling the amount of oil has the effect of providing the most efficient lubrication.

[Brief description of the drawings]

FIG. 1 is a sectional view of a cylinder head according to an embodiment of the present invention, which is a longitudinal sectional view taken along line AA of FIG.

FIG. 2 is a top view of the cylinder head showing the embodiment of the present invention.

FIG. 3 is a sectional view taken along line CC of FIG. 1;

FIG. 4 is a sectional view taken along line BB of FIG. 2;

FIG. 5 is a plan view of a main part showing a conventional cylinder head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder head 2 Push rod hole 3 Push rod hole 5 Vertical rib 6 Horizontal rib 7 Horizontal rib 8 Ceiling 9 Cooling water chamber 10 Notch 11 Notch 12 Exhaust port 13 Notch 14 Notch 17 Cylinder 22 Head bolt hole 23 Head Bolt hole 29 Lubricating oil passage 30 Lubricating oil passage

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02F 1/24 F02F 1/40

Claims (6)

(57) [Claims] 1. A bolt which is inserted through a cylinder head so as to surround a cylinder and which tightens and fixes the cylinder head to a cylinder block. The bolt corresponds to a head bolt located outside a push rod hole of the cylinder head. A vertical rib for transmitting the tightening force of the head bolt to the center of the cylinder head seating surface of the cylinder block is integrally formed on the inner surface of the cylinder head. A cylinder head for an internal combustion engine, wherein a horizontal rib for transmitting a tightening force of the head bolt to the vertical rib is formed integrally with at least one of an upper surface and a lower surface of a ceiling portion of the cylinder head. 2. A cylinder for an internal combustion engine according to claim 1, wherein a horizontal rib is provided in a cooling water chamber at a lower surface of a ceiling portion of the cylinder head, and a part of the horizontal rib is cut off to form an air passage. head. 3. A cylinder head for an internal combustion engine according to claim 2, wherein a horizontal rib is provided at a position to limit a flow rate of the cooling water flowing above the exhaust port in the cylinder head. 4. A horizontal rib is provided on an upper surface of a ceiling portion of a cylinder head, and a cutout for passing lubricating oil from a center side of the cylinder head toward a push rod hole is formed in the horizontal rib. The cylinder head for an internal combustion engine according to any one of claims 1 to 3. 5. A device in which notches for lubricating oil are provided corresponding to both a push rod hole for an exhaust valve and a push rod hole for an intake valve, wherein a push rod hole which requires a larger amount of lubricating oil is provided. 5. The cylinder head according to claim 4, wherein the corresponding notch is larger than the other notch. 6. A cylinder head having horizontal ribs provided on both upper and lower surfaces of a ceiling portion thereof, wherein a notch for passing lubricating oil flowing from the center of the cylinder head toward the push rod hole is provided in the upper horizontal rib, and a lower horizontal rib is provided in the lower horizontal rib. 2. A cylinder head for an internal combustion engine according to claim 1, wherein notches for the air passage are formed, and the upper and lower horizontal ribs overlap each other.