JPS61132755A - Cylinder head structure - Google Patents

Abstract

PURPOSE:To improve strength to an expansion pressure and to form a uniform cooling water flow, by a method wherein a conical partition is formed integrally between the upper and the lower surface of a cylinder head. CONSTITUTION:A conical partition 20 is integrally formed in a cylinder head 2. The conical partition 20 has the one end integrally formed along an outer side part 21 of the upper surface of the cylinder head 2 and the other end formed such that the forward end is extended so as to surround a fuel injection nozzle containing cylinder part 8 and excellently control a cooling water flow in a jacket chamber 14. This permits improvement of rigidity of the cylinder head through dispersion of a load produced due to a expansion pressure in a cylinder and uniform production of a cooling water flow.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cylinder head of an internal combustion engine, and in particular, to regulating the flow of cooling water in the cylinder head, improving the rigidity of the cylinder head, and improving weight reduction. related to the cylinder head structure.

[Prior Art] Generally, the cylinder head of an internal combustion engine is exposed to explosion pressure and high-temperature combustion gas within the cylinder, and therefore requires sufficient strength and cooling.

Conventionally, a cylinder head structure as shown in FIG. 11 is known.

In the figure, a cylinder head 2 is provided in close contact with the upper part of a cylinder 1 via a gasket, etc., and a piston 4 having a combustion chamber 3 recessed at the top so as to be reciprocally movable is provided in the cylinder 1. It is being

On the other hand, combustion air is supplied into the cylinder head 2 from its upper outer periphery into the cylinder chamber 5 formed by the cylinder 1, the cylinder head 2, and the piston 4, or is discharged from the cylinder chamber 5 to the outside. intake/exhaust passages 6.7 are formed.

The intake/exhaust passages 6, 7 are opened from the upper outer part 21 of the cylinder head 2, and the other end is connected to the cylinder chamber 5.
It is formed in communication with. In addition, the intake/exhaust passages 6, 7
A fuel injection nozzle accommodating cylindrical part 8 is formed between the cylinder head 2 and the cylinder head 2, which is opened from the upper part of the cylinder head 2, communicates with the cylinder chamber 5, and injects fuel into the cylinder chamber 5.

On the other hand, between the upper end surface of the cylinder head 2 and the intake/exhaust pipe walls 9, 10 forming the intake/exhaust passages 6.7, respective valves are housed integrally therewith and communicating with each other. Cylinder 1
1.12 is provided.

In order to protect the inside of the cylinder 1 and the cylinder head 2 from the high heat of combustion gas, a jacket pipe 13 and a jacket chamber 14 are formed to circulate cold HI water therein.

Specifically, a jacket pipe 13 is formed in the cylinder 1 to circulate cooling water so as to surround the cylinders 5 to 5. Further, a discharge port 15 communicating with the jacket pipe 13 is opened on the upper end surface of the cylinder 1, and
An introduction port 16 is opened in the lower end surface of the cylinder head 2 to engage with the discharge port 15 and to introduce the cooling water in the jacket pipe 13 into the cylinder head 2 for cooling.

Furthermore, the above-mentioned intake/exhaust pipe wall 9.10. Fuel injection nozzle housing cylinder part 8. A space within the cylinder head 2 surrounding the valve housing cylinders 11 and 12 is formed as a jacket chamber 14 into which the cooling water is introduced and circulated, and the cooling water flow introduced and circulated from the introduction port 16 into the jacket chamber 14 is as follows: This cools the intake/exhaust valves, etc. housed in the cylinder head 2 and its various parts, and allows them to operate properly.

By the way, the cooling water flow introduced into the cylinder head 2 is regulated to form a good cooling water flow to uniformly cool the cylinder head 2, and to obtain sufficient structural strength against the explosion pressure in the cylinder chamber 5. Therefore, each of the above
A horizontal partition wall 18 is integrally formed along the inner wall of the cylinder head 2 so as to be integrally fitted into the exhaust pipe walls 9, 10 and the fuel injection nozzle housing cylinder part 8, and further, the horizontal partition wall 18 is integrally formed along the inner wall of the cylinder head 2. A communication portion 19 such as a communication port or a cutout portion is formed around the fuel injection nozzle housing cylinder portion 8 at 18 to communicate with the upper and lower jacket chambers 14 to regulate and circulate cooling water.

[Problems to be Solved by the Invention] However, the explosion pressure and force generated in the cylinder due to combustion increases in proportion to the load of the engine, and the pressure is applied to the cylinder from the bottom side of the cylinder head 2. head 2
Can be hung on. That is, in order to make the horizontal partition wall 18 for improving the rigidity of the cylinder head 2 have sufficient strength against the pressure, the lower wall 3 of the cylinder head 2 must be
2 or the horizontal partition wall 18 to ensure sufficient cross-sectional strength.Alternatively, a rib may be provided in the direction of deformation of the horizontal partition wall 18.

However, thickening of the partition wall 18 causes an increase in the temperature of the surface of the lower wall 32, resulting in a decrease in material strength and thermal stress.

In addition, when designing a groove, increasing the wall thickness increases weight and cost, and the structure of ribs and the like becomes complicated, both of which have been pointed out as having drawbacks.

[Object of the invention] The present invention was created to solve the above problems, and
An object of the present invention is to provide a lightweight cylinder head structure that has sufficient strength to withstand explosion pressure within the cylinder, and that satisfactorily regulates the flow of cooling water within the cylinder head to form a uniform flow of cooling water. It's about doing.

[Summary of the Invention] In order to achieve the above object, the present invention integrates a conical partition wall between the upper and lower surfaces of the cylinder head that disperses the explosion pressure received from within the cylinder and regulates the flow of cooling water within the head. The partition wall effectively disperses the explosion pressure generated within the cylinder to each part of the cylinder head, allowing each part to share the load due to the pressure, making it possible to reduce the weight of the cylinder head. Also,
The cooling water flow inside the head is well regulated and cooled uniformly and efficiently.

[Embodiment] A preferred embodiment of the present invention will be described below with reference to the accompanying drawings.

As shown in FIG. 1, 4 is a combustion chamber 3 recessed at the top.
1 is a cylinder that reciprocally accommodates the piston 4, and 2 is a cylinder head that is detachably attached to the upper end surface of the cylinder 1 via a gasket.

As mentioned above, when fuel and combustion air are introduced into the cylinder chamber 5 formed by the cylinder 1, the piston 4, and the cylinder head 2 and are compressed and combusted, the internal pressure in the cylinder chamber 5 (
explosion pressure) increases and cylinder 1. This will place a load on the piston 4 and cylinder head 2. In addition, sufficient cooling is required because the high heat generated at this time is directly or thermally conducted to each part.

Therefore, in the embodiment of the present invention, the cylinder head structure is constructed as follows from the viewpoint of increasing the strength and weight of the cylinder head 2, and reducing the cooling capacity.

As shown in FIG. 1, intake and exhaust passages 6 and 7 are formed in the cylinder head 2, opening from the upper outer part 21 and communicating with the cylinder chamber 5 at the other end. A fuel injection nozzle accommodating cylindrical portion 8 that extends to the upper surface of the cylinder head 2 and injects fuel is formed on the lower surface of the cylinder head 2 between the cylinder head 2 and the cylinder head 2 . In addition, the intake/exhaust pipe wall 9°1 forming the outer shell of the intake/exhaust passage 6.7 is
0 and the upper surface of the cylinder head 2 is an intake/exhaust valve (not shown) that opens and closes to appropriately control opening and closing of the intake/exhaust passage 6.7 and the cylinder chamber 5. Valve cylinders 11 and 12 for accommodating rods are integrally formed.

In addition, inside the cylinder head 2, the above-mentioned intake/exhaust pipe wall 9.1
0. Fuel injection nozzle housing cylinder part 8. Except for the valve number cylinders 11 and 12, a hollow jacket chamber 14 is formed for cooling by circulating cooling water. A plurality of communication portions 19 are formed that engage with the outlet 15.

Now, in the cylinder head 2, a conical partition wall 20 is integrally formed in order to cope with the explosion pressure generated within the cylinder chamber 5, and the conical partition wall 20 achieves increased strength and weight reduction at the same time. It is something to do.

Specifically, the outer part 21 of the upper surface of the cylinder head 2
One end is integrally provided along the fuel injection nozzle accommodating cylindrical portion 8 and the other end is appropriately extended so as to appropriately regulate the flow of cooling water in the jacket chamber 14. A conical partition wall 20 is formed as an extension, and one side of the conical partition wall 20 is integrated with the intake/exhaust pipe walls 9, 1o forming the intake/exhaust passages 6, 7. The other end of the conical partition wall 20 is integrated with the outer circumferential portion of the fuel injection nozzle accommodating cylindrical portion 8 to form a communication portion 19 (hole or notch) that regulates and guides the cooling water into the jacket chamber 14. Functionality can be further improved.

Further, the cylinder head 2 is provided with a mounting hole 22 penetrating from the upper part to the lower part thereof, and a tightening bolt 23 is inserted into the mounting hole 22 to be integrated with the cylinder 1.

Therefore, the explosion pressure in cylinder 1 is equal to the pressure in cylinder head 2.
When a load is applied to the lower surface of the cylinder head 2, the load is applied to the lower surface of the cylinder head 2.
Load is applied to each part that forms the

However, if explained using the structural model of the cylinder head 2 shown in FIG. A conical partition wall 20, which is partially integrated with the intake/exhaust pipe walls 9 and 10, forms a first ．． A second triangular structure 25,26 is formed. In addition, the conical partition wall 20 and the intake/exhaust pipe wall 9
, 10 is connected to a valve number capacity section 11 connected to the upper surface of the cylinder head 2. A second triangular structure 27 is formed in which the apex is twisted to the right in the opposite direction to the second triangular structure. Roughly speaking, since the intake/exhaust pipe walls 9 and 10 are integrated with the outer part 21 of the cylinder head 2, the above-mentioned No. 1. The second triangular structure is divided into a third triangular structure 28 and a second rectangular structure 29 .

That is, the load applied from the lower surface side of the cylinder head 2 is mainly applied to the first rectangular structure 24, but
The strength is improved because it is made rigid by
Since these are further divided into various triangular or rectangular structures and each part is made rigid, the stress applied to the cylinder head 2 is only tension and compression, and moment loads such as bending are eliminated.

Therefore, by setting the wall thickness and section modulus of each part based on the allowable tensile load of the material constituting the cylinder head 2, a cylinder head structure that is lightweight and has high strength can be obtained.

Further, as shown in FIG. 3, the strength of the cylinder head structure can be further improved by integrating the partition wall 20 along the fuel injection nozzle accommodating cylinder section 8 and providing sufficient cooling in the jacket chamber 14 at the bottom thereof.

FIG. 4 shows a cylinder head 2 in which a conical partition wall 20 that regulates the flow of cooling water and improves its strength is integrated with intake and exhaust pipe walls 9 and 10.
A plurality of attachments extending outward from the upper outer peripheral portion of the flange 30 are integrated into the attachment holes through bolts 23.

FIG. 5 is a top view of FIG. 4.

Next, another embodiment of the cylinder head structure of the present invention will be described based on FIGS. 6 to 10.

As shown in FIG. 6, in the cylinder head 2, one end side is joined along the upper outer circumference of the fuel injection nozzle housing cylinder part 8, and the other end side is joined to the lower outer part 3 of the cylinder head 2.
a conical partition wall 20 connected to 1 and integrated into an upwardly convex shape;
It shows. To explain this using a structured model shown in FIG. 7, the partition wall 20 creates the first rectangular structure 24
is broadly divided into first and second triangular structures 25 and 26.

Therefore, the cylinder head 2 is formed in a truss shape, and a tensile load is applied to the conical partition wall 20. Further, since the load is distributed to each part, a lightweight and high-strength cylinder head 2 similar to the above embodiment can be obtained.

FIG. 8 shows the cylinder head 2 in the embodiment shown in FIG.
An example is shown in which the member forming the upper surface of is removed.

That is, this shows that if the conical partition wall 20 has a sufficient cross-sectional area (with respect to the load), it can be removed because it has a truss (triangular) structure as shown in the structural model of FIG. ing. Furthermore, the structured model in FIG. 10 shows an example in which the above-mentioned conical partition wall 20 is provided in substantially the same way as the actual bar example shown in FIG. 1, and the structured model in FIG. - This is the top surface of RAD 2 removed. This shows that, as mentioned above, by setting the triangular structure and the cross section of the member to have sufficient strength, it is possible to obtain a cylinder head structure that is light in heat and has high strength.

[Effects of the Invention] As explained above, according to the present invention, the following effects can be exhibited.

(1) Since the conical partition wall that regulates the flow of cooling water and improves the rigidity of the cylinder head structure is integrally formed in the cylinder head, a lightweight and simple cylinder head structure can be obtained.

(2) Since a highly rigid cylinder head can be formed by the conical partition, the wall thickness of each member can be reduced and cooling can be performed efficiently.

(3) Since the flow of cooling water can be well regulated, uniform cooling can be achieved.

(4) By providing the conical partition wall in a triangular structure within the cylinder head, the structure receives the load due to the explosion pressure within the cylinder in a distributed manner, resulting in high strength and cost reduction.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view showing a preferred embodiment of the present invention, and FIG.
The figure shows a structured model of Fig. 1, and Fig. 3 shows a structured model in which the conical partition shown in Fig. 1 is integrated into the fuel injection nozzle housing cylinder to further increase rigidity. FIG. 4 is a schematic perspective view showing an example in which intake and exhaust pipe walls are integrated with the conical partition wall of the present invention to form parts, FIG. 5 is a top view of FIG. 4, and FIGS. 6 to 10 are Figure 1 showing another embodiment of the present invention.
FIG. 1 is a diagram showing a conventional cylinder head structure. In the figure, 1 is a cylinder, 2 is a cylinder head, 3 is a combustion chamber, 4 is a piston, 5 is a cylinder chamber, 6.7 is an intake/exhaust passage, 8 is a fuel injection nozzle housing cylinder, 9.10 is an intake/exhaust passage. Exhaust pipe wall, 11.12 is collection cylinder, 13 is jacket pipe, 1
4 is a jacket chamber, and 20 is a conical partition.

Claims (1)

[Claims] A cylinder head structure characterized in that a conical partition wall is integrally formed between the upper and lower surfaces of the cylinder head to disperse explosion pressure received from within the cylinder and to regulate the flow of cooling water within the head.