JPS5912124A - Inlet port of internal combustion engine - Google Patents

Abstract

PURPOSE:To strengthen swirl and to improve volumetric efficiency by a method wherein, in an inlet port provided with a swirl part at an inlet introducing port and around an inlet valve, arrangement of inlet port for cylinder, distance between the center of cylinder chamber and the stem of inlet valve etc. are improved. CONSTITUTION:The helical inlet port P1 comprises an inlet introducing part 9 and a divided swirl part 20 communicating to the introducing part 9 to be centered on the valve stem A0 of an inlet valve 11. In this case, the swirl part 20 is arranged from the surface of a cylinder chamber 30 containing a shaft center C0 to the valve stem center A0 of the inlet valve 11 while the helical channel 13 of the swirl part 20 is formed of continuous curve centered on the helical stem centers R1-R5 exceeding at least each two of them. The inlet port P1 shall be arranged on the relative position of -45 deg.<=theta<=45 when the valve stem center A0 assumes its opposite angle against a line Z3 connecting to the diameter center C0 of multiple cylinder chambers 30 to be theta. Besides, the expression of 0<=r/D<=0.25 shall be satisfied assuming the distance from said shaft center C0 to the valve stem center A0 to be (r) and the diameter of cylinder chamber to be D.

Description

[Detailed Description of the Invention] The present invention provides a highly efficient swirl in the cylinder chamber.
Generate and maintain it. The present invention also relates to an intake boat for an internal combustion engine that can increase volumetric efficiency.

Conventionally, there is a so-called helical intake boat for internal combustion engines, which has a swirl section around the intake inlet and intake valve in order to increase the total swirl in the cylinder chamber to improve combustion.

This helical intake boat. Because it has the spiral part.
Swirl can be strengthened. However, on the other hand, there are technical drawbacks such as a decrease in volumetric efficiency due to an increase in flow path loss.

As a means of alleviating such defects. Various methods have been tried in the past, but none have been found to be effective at both strengthening the swirl and improving volumetric efficiency.

That is, for a conventional helical intake boat.

The spiral flow path of the spiral part is configured with a single spiral axis placed eccentrically with respect to the valve axis of the intake valve. In addition, there are specific values for the arrangement position in the intake boat relative to the cylinder chamber, the distance between the center of the cylinder chamber and the valve axis of the intake valve, the ratio of the cylinder chamber diameter to the intake valve seat diameter, etc. According to such an intake boat, the inflow velocity distribution of intake air from the intake valve into the bore of the cylinder chamber is large in the central part of the cylinder chamber, and is large in the peripheral part tangential to the cylinder chamber. is a small percentage.In this case.

The swirls formed in the cylinder chamber interfere with each other and attenuate, and in extreme cases, disappear, resulting in no increase in size.

Therefore, the present inventors investigated the arrangement position of the intake boat of an internal combustion engine relative to the cylinder chamber, the distance between the center of the cylinder chamber and the valve axis of the intake valve, the ratio of the cylinder chamber diameter to the intake valve seal diameter, and the cylinder chamber diameter and piston stroke. This is the result of research aimed at finding a balance between strengthening the swirl and improving volumetric efficiency, as well as simplifying manufacturing as much as possible, regarding the relationships between the two and their combinations. The present invention has been devised to solve the above-mentioned conventional problems.

That is, the present invention... and an introduction part that circulates the intake air.

An intake boat is provided in the cylinder head of an internal combustion engine, and is provided in the cylinder head of an internal combustion engine, and is provided in the cylinder head of an internal combustion engine. An intake boat for an internal combustion engine having a passage formed by a curve centered on a helical axis on at least two layers, wherein the valve shaft of the intake valve is a diagonal angle pipe θ with respect to a line connecting a plurality of cylinder chamber diameter centers. Then.

This is an intake boat for an internal combustion engine arranged at a position in the relationship of -45° (0<45° (hereinafter referred to as the first invention).

In addition, the present invention provides an intake boat that is composed of an introduction part through which the entire intake air flows, and a swirl part that communicates with the introduction part to form a section around the valve shaft of the intake valve and communicates with the cylinder chamber. is provided in the cylinder head of an internal combustion engine, and the spiral passage of the spiral portion is constructed of a curved line with the entire center of the helical axis on at least two layers. If the distance to the shaft is γ and the cylinder chamber diameter iD, then the ratio of the two is 0.
This is an intake boat for an internal combustion engine (hereinafter referred to as the second invention) characterized in that the intake boat is in a range that satisfies the relationship of <γ/D (0, 25).

Furthermore, the present invention provides an intake air flow system which is composed of an introduction part through which intake air flows, and a swirl part that communicates with the introduction part and is partitioned around the valve shaft of the intake valve and communicates with the cylinder chamber. An intake boat for an internal combustion engine is provided in the cylinder head of an internal combustion engine, and the spiral passage of the spiral portion is formed by a curved line centered on the helical axis at least two layers above, wherein the seat diameter of the intake valve is d. , If the diameter of the ring chamber is D, the ratio between the two is within a range satisfying the relationship of 0.58 (d/D (0,44 This is an internal combustion engine intake boat.

In addition, the present invention provides an intake boat that generates a vortex in the intake air, which is composed of an introduction part through which intake air flows, and a swirl part that communicates with the introduction part and forms sections around the valve shaft of the intake valve and communicates with the inside of the cylinder chamber. is provided in the cylinder head of the internal combustion engine, and the spiral passage of the spiral portion is configured by a curve centered on the helical axis on at least two layers, wherein the ratio of the two is 1.0 ≦ S/D≦1.2, and at least the first. This is an intake boat for an internal combustion engine that is combined with either one of the second inventions.

According to the intake boat of each of the above inventions, by setting each of the above numerical ranges, the inflow velocity distribution of intake air from the intake valve into the bore of the cylinder chamber with respect to the bore of the cylinder chamber is controlled in the peripheral portion tangential to the cylinder chamber. The ratio is extremely large in the central part of the cylinder chamber, and the ratio is small in the central part of the cylinder chamber. For this reason, the flow formed in the cylinder chamber becomes an overall vortex flow along the bore, and the swirl is stable and flows smoothly with little turbulence, making it possible to significantly strengthen the swirl, and also to reduce flow loss. The total volumetric efficiency can be increased.

1 to 4 show an embodiment of the first invention,
The intake boat PL of the internal combustion engine E consists of an introduction part 9 through which all intake air flows, and a spiral part 20 that communicates with the introduction part 9 and communicates with the cylinder chamber 60 around the valve shaft Ao of the intake valve 11. The intake boat P1 configured as described above generates a swirl in the intake air, and is provided in the cylinder head 12 of the internal combustion engine. The introduction portion 9 is disposed from the open end of the cylinder head 12 to extend around the axis 0° of the cylinder chamber 60 and around the valve axis A0 of the intake valve 11 from within the plane.

This spiral portion 20 is constituted by a series of curves having the spiral passage 13, which is the peripheral wall thereof, as the entire center of the spiral axis on at least two layers. In this embodiment, five helical axes Rt,
Rx, Rt, and R are also made of +R8, and the circular arc that surrounds them forms the wall metal surrounding the spiral passage 130.

In addition, the broken line in FIG. 1 shows the conventional structure in which the circumferential wall of the spiral passage 80 is formed with one spiral axis Ro. Furthermore, the intake boat P1 of this embodiment has a valve shaft AO of the intake valve 11.
Assuming that the sound for the top is zero with respect to the line Z1 connecting the aperture centers of the plurality of cylinder chambers 50, -45°≦0da45
It is arranged at a position relative to the angle (area indicated by a broken line in FIG. 6).

In the internal combustion engine of this embodiment having the above configuration, the intake boat PI has the valley cylinder chamber 3 of the four cylinders as described above.
Intake valve 1 relative to the line Z- that connects the diameter (bore) center C6 of 0
The fact that the valve shaft A of No. 1 is arranged at a position where the vertical angle θ satisfies -45''≦θ≦45° promotes stability 1 and smooth circulation.

The intake air flowing down this spiral portion 20 flows along the spiral passage 16.

At this time, according to the intake boat PI of this embodiment.

The inflow velocity distribution of intake air from the intake valve 11 into the bore of the cylinder chamber 30 with respect to the bore of the cylinder chamber 30 is as follows.

It is extremely large in the peripheral part tangential to the cylinder chamber 60,
It is said that the central portion of the cylinder chamber 60 is small. In other words, the ratio can be set to be larger in order from the central portion of the cylinder chamber toward the peripheral portion tangential to the cylinder chamber.

Therefore, the flow formed in the cylinder chamber 60 becomes an overall vortex flow along the cylinder chamber bore, and the vortex flow is stable and flows smoothly without any interference with each other, with little turbulence. As shown, the entire swirl can be greatly strengthened.

In addition, according to the intake bow) P+ of this embodiment, the interference of the flow in the cylinder chamber is reduced, and as a result, the loss is slightly reduced, and the volumetric efficiency is stabilized as shown by curve Y in Fig. 4. 1. Smooth practical use It is possible to set a predetermined value that satisfies the above.

The above-mentioned vertical angle θ does not affect the swirl and has a very large influence, and as shown in FIG. Swirl will be smaller if it is set more closely. That is, even without changing the flow path shape of the intake boat, a large swirl can be formed by arranging the intake boat at an appropriate position relative to the bore center a. This is because the spiral flow flowing into the cylinder chamber 30 from the intake valve 11 follows the bore of the cylinder chamber 60 in the range of the vertical angle 0, whereas the spiral flow flows from the intake valve 11 into the cylinder chamber 30 outside the range of the vertical angle θ. This is because the flow flowing in collides with the cylinder wall, making it difficult to form a flow (swirl) along the peripheral wall of the cylinder chamber 60. That is, in order to strengthen the swirl, it is important to form a flow (swirl)' (i-) along the circumferential wall of the cylinder chamber 60 without any loss in the flow flowing into the cylinder chamber 60 from the intake valve 11.

In summary, the intake boat Pl of this embodiment can achieve enhanced swirl and improved volumetric efficiency by having the above configuration, and the fuel temperature of the internal combustion engine in Figures 5 and 6 is as follows.
This is an embodiment of the second invention, and to focus on the differences from the previous embodiment, an intake boat P2 of an internal combustion engine is connected to the valve shaft of the intake valve 11 from the diameter (bore) center C of the cylinder chamber 30. A. Distance to? γ and the diameter (bore diameter) of the cylinder chamber 60 are 9, and the configuration is such that the ratio between the two satisfies the relationship 0≦γ/D≦0.25.

As described above, the intake boat P2 of the internal combustion engine E2 of this embodiment having the above-mentioned configuration has the cylinder chambers 5 of each of the four cylinders.
The ratio of the distance r from the bore center Oo of 0 to the valve axis A of the intake valve 11 and the bore diameter of the cylinder chamber 30 is 6o≦1/D≦
By arranging the intake air in a range that satisfies the relationship of 0.25, the intake air introduced into the cylinder chamber 60 is efficiently, stably and smoothly circulated through the spiral passage 13 of the spiral part 20 from the introduction part 9. The intake air flowing down this spiral portion 20 is in the spiral passage 1
3, and at this time, the intake boat p of this embodiment
According to @, the intake valve 11 is connected to the bore of the cylinder chamber 50.
The inflow velocity distribution of intake air into the bore of the cylinder chamber 30 is extremely large in the peripheral portion tangential to the cylinder chamber 30 and small in the central portion of the cylinder chamber 30. In other words, the ratio can be set to be larger in order from the central portion of the cylinder chamber toward the peripheral portion tangential to the cylinder chamber.

For this reason, the flow formed within the cylinder chamber 30 becomes an overall vortex flow along the cylinder chamber bore, and the vortex flow is stable and flows smoothly without any turbulence and interference with each other, resulting in a curve X2 in FIG. As shown, the swirl can be greatly strengthened. In addition, the intake boat P of the three embodiments
According to No. 3, the flow interference in the cylinder chamber is reduced, and the loss can be reduced as a result.

The above γ/D has a very large influence on the swirl.
As shown in the figure, the valve axis of the intake valve 11 is AOi, the bore center of the cylinder chamber 30 is Oo
Also, if it is provided with respect to the bore diameter, the swirl becomes smaller. That is, even without changing the flow path shape of the intake boat, a large swirl can be formed by arranging the intake boat at an appropriate position relative to the bore center C. This is from the intake valve 11 to the cylinder chamber 3.
The spiral flow flowing into the cylinder chamber 60 follows the bore of the cylinder chamber 60 in the range of 1/D, while flowing into the cylinder chamber 3° from the intake valve 11 outside the range of γ/D. When the flow collides with the cylinder wall.

This is because a flow (swirl) along the circumferential wall of the cylinder chamber 300 is difficult to form. That is, in order to strengthen the swirl, it is necessary to form a flow (swirl) along the circumferential wall of the cylinder chamber 3° without any loss in the flow flowing into the cylinder chamber 6o from the intake valve 11.

In summary, the intake boat P2 of this embodiment can achieve all the improvements in upper L' efficiency, improve the combustion of the internal combustion engine, improve the output, improve the fuel efficiency, etc. The amount of nitrogen flowing into practical use of 4 is as described above. As long as θ and γ/D are within the range, there will be no change at all.

FIGS. 2 and 7 show other embodiments of the present invention 1. Mainly, the differences from the above-mentioned embodiments are as follows: 9. The intake boat of the internal combustion engine of this embodiment has at least the first. In addition to either one of the second inventions, if the seat diameter fd of the intake valve 11 is taken as the entire diameter (bore diameter) of the cylinder 6 - the cylinder chamber 60, the ratio of the two is 0.68 ≦ d/D ≦ 0. This configuration is arranged in a range that satisfies the relationship of .44.

In another embodiment of the present invention having the above configuration, the seat diameter d of the intake valve 11 relative to the bore diameter is 0.68≦d/D≦0.4.
If it is in the range of 4, the volumetric efficiency and swirl tend to be satisfactory as shown in Figure 7, and 0 to 40 to 1%. ≦d/
It is preferable that D≦0.44.

To be more specific, in another embodiment of the present invention, the intake air introduced into the cylinder chamber 30 is introduced into the introduction section. Spiral passage 1 of spiral part 20
3 promotes efficient, stable and smooth distribution. The entire intake air flowing down this spiral portion 20 flows along the spiral passage 13,
According to the intake boat according to another embodiment of the present invention, the inflow velocity distribution of intake air from the intake valve 11 into the bore of the cylinder chamber 30 is tangential to the cylinder chamber 60. It is said that it is extremely large in the peripheral part and small in the central part of the cylinder chamber 30. In other words, the ratio can be set to be larger in order from the central portion of the cylinder chamber toward the peripheral portion tangential to the cylinder chamber.

1 For this reason, the flow formed within the cylinder chamber 3o becomes an overall vortex flow along the cylinder chamber bore, and the vortex flow has little turbulence and is stable without interfering with each other. As shown in the figure, the swirl can be greatly strengthened. Moreover, according to the intake boat of this embodiment, the pressure loss in the intake spiral passage 16 and the flow interference in the cylinder chamber are reduced, and the volumetric efficiency is 7th overall.
As shown by curve Y3 in the figure, it can be increased to a predetermined value that is practically satisfactory.

The effect of d/D on swirl is extremely large <N
'r Shown in Figure 7 f Y: , 0.38〈d/D
Deviation from the range <a44 will reduce the swirl.

That is, even if the shape of the flow path of the intake boat is not changed, at least the first. In addition to one of the second inventions, the bore center is 0. By setting the seat diameter df of the intake valve 11 to an appropriate value, a large swirl can be formed. This is because the spiral flow flowing into the cylinder chamber 60 from the intake valve 11 follows the bore of the cylinder chamber 60 within the range of d/D, whereas outside the range of d/D, the spiral flow flows from the intake valve 11 into the cylinder chamber. This is because the flow flowing into the chamber 60 collides with the cylinder wall, and a flow (swirl) along the peripheral wall of the cylinder chamber 60 is less likely to be formed. That is, in order to strengthen the swirl, it is necessary to completely form a flow (swirl) along the circumferential wall of the cylinder chamber 30 without loss of the flow flowing into the cylinder chamber 60 from the intake valve 117Jk.

In summary, the intake hoard according to the other embodiment of the present invention can strengthen the cis-swirl and improve the volumetric efficiency +S by having the above structure.

Improves combustion in internal combustion engines and increases output 1. It has many practical effects such as improving fuel efficiency.

FIGS. 2 and 8 show other embodiments of the present invention, and the differences from each of the previously described embodiments will be mainly described.

The intake boat of the internal combustion engine of this embodiment has at least the first.
In addition to either one of the second aspects of the invention, if the stroke Is of the piston PG reciprocates in parallel to the axial direction within the cylinder chamber 30, and the bore diameter pipe 1) of the cylinder chamber 60, the ratio of the two is 1. This configuration satisfies the relationship 0≦S/D of 1.2.

The embodiment of the present invention having the above configuration has a piston P for a 9-bore diameter as described above. Stroke Si1.0≦B/
This is an internal combustion engine set within the range of D≦1.2, and FIG. 8 shows the relationship between swirl and volumetric efficiency with respect to S/D.

Although the volumetric efficiency does not change, it is desirable to set the swirl within the above range.

Regarding the problem related to piston speed, if S is too large, friction will increase, and there is an optimum range, which is the above numerical range.

To be more specific, in the embodiment of the present invention, the intake air introduced into the cylinder chamber 60 is passed from the introduction part 9 to the spiral passage 13 of the spiral part 20.
Promote efficient, stable and smooth distribution. The intake air flowing down this spiral portion 20 flows along the spiral passage 13, and at this time, according to the intake boat of the embodiment of the present invention, the intake air flows from the intake valve 11 into the bore of the cylinder chamber 30 with respect to the bore of the cylinder chamber 30. The inflow velocity distribution of the intake air in the cylinder chamber 6 is
It is extremely large in the peripheral part tangential to 0, and the cylinder chamber 3
It is said that it is small in the central part of 0. In other words, the opening can be made larger in order from the central portion of the cylinder chamber toward the peripheral portion tangential to the cylinder chamber.

For this reason, the flow formed within the cylinder chamber 30 becomes an overall vortex flow along the cylinder chamber bore, and the vortex flow is stable and flows smoothly without interfering with each other, with little turbulence, resulting in curve X4 in FIG. As shown, the entire swirl can be greatly strengthened. Further, according to the intake boat according to the embodiment of the present invention, flow interference in the cylinder chamber is reduced.

The loss is reduced, and the volumetric efficiency can be brought to a stable and smooth predetermined value that is practically satisfactory, as shown by curve Y4 in FIG.

The value of S/D has a very large influence on the swirl, and as shown in Figure 8, the value of S/D is 1.0 (S/D≦1.
Swirl will become smaller if it completely deviates from the range of 2.

That is, even if the shape of the flow path of the intake boat is not changed, at least the first. In addition to any one of the second invention, the S/D
By setting the value of to a value within the numerical range, a large swirl can be formed. This is because the spiral flow flowing into the cylinder chamber 30 from the intake valve '11 follows the bore of the cylinder chamber 60 in the range of S/D, whereas it flows from the intake valve 11 outside the range of S/D. This is because the flow flowing into the cylinder chamber 30 collides with the cylinder wall, making it difficult to form a flow (swirl) along the peripheral wall of the cylinder chamber 60. That is, in order to increase the swirl noise, it is necessary to form a flow (swirl) along the circumferential wall of the cylinder chamber 300 without any loss in the flow flowing into the cylinder chamber 60 from the intake valve 11.

In summary, the above embodiment of the intake boat according to the present invention is as follows:
With the above structure, it is possible to strengthen the swirl and improve the volumetric efficiency, thereby improving the combustion of the internal combustion engine, thereby producing many practical effects such as improving the output and improving the fuel efficiency.

Next, the intake boat of the internal combustion engine according to another embodiment of the present invention is arranged in a position relative to the cylinder chamber 60 in the intake boat, as shown in FIGS. 2 and 9. , that is + '+ ii J note - 45 note 45° g0g45≦γ/D
≦0.25, then the -45° angle θg 45°, at least one of 0≦γ/D≦0, 25, and the bore diameter of the cylinder chamber 60. Let us consider the ratio of 8 of the seat diameter of intake air to JPll as the relationship of 038≦d/D≦0.44 &l, or ￥
The bore diameter of the ring chamber 60 and the stroke S of the piston p
In other words, the relationship 1.0≦S/D≦1.2 is satisfied, or at least one of them is combined with gold.

In the intake boat of the internal combustion engine in another embodiment having the above configuration, the intake air introduced into the cylinder chamber 60 is stably and smoothly circulated and propelled by the spiral passage 15 of the volute part 20 from the intake air introduction part 9. The intake air flowing down the spiral portion 20 flows along the spiral passage 16, and according to another embodiment of the intake boat of the present invention, the intake air flows from the intake valve 11 to the bore of the cylinder chamber 30. The inflow velocity distribution of intake air into the bore is extremely large in the peripheral part of the cylinder chamber 5 (IK tangential part) and small in the central part of the cylinder chamber 30.In other words, The ratio can be set such that the ratio gradually increases toward the peripheral portion that is tangential to the curve.

For this reason, the flow formed within the cylinder chamber 30 becomes an overall vortex flow along the cylinder chamber bore, and the vortex flow is stable and flows smoothly without any turbulence and interference with each other, resulting in curve X in FIG. As shown in the figure, the swirl can be greatly strengthened. According to this FIG. 9, the above, θ
, γ/D are both out of the above numerical range, the drop is sharp.

Each of the above θ, γ/D, d/D, and 8/D has a very large influence on the swirl, and if each deviates completely from the above-mentioned numerical range, the swirl becomes small.

That is, even without changing the flow path shape of the intake boat, a large swirl can be formed by arranging the intake boat at an appropriate position relative to the bore center a. This is because the spiral flow flowing into the cylinder chamber 60 from the intake valve 11 is
/D range, it follows the bore of the cylinder chamber 60, while outside the range of θ, γ/Dd/D, B/D, the intake valve 11
This is because the flow flowing into the cylinder chamber 30 collides with the cylinder wall, making it difficult to form a flow (swirl) along the peripheral wall of the cylinder chamber 30. Namely.

To make the swirl stronger, from the intake valve 11 to the cylinder chamber 60.
The problem lies in how much the flow flowing into the cylinder chamber 60 can be completely formed as a swirl along the peripheral wall of the cylinder chamber 60 without loss.

In summary, the intake boat of other embodiments of the present invention is as follows:
With the above configuration, it is possible to strengthen the swirl and improve the volumetric efficiency, and it has many practical effects such as improving the combustion of the internal combustion engine, increasing the output, and improving the fuel efficiency.

25　　　　　　　　　　　-1ri

[Brief explanation of drawings]

Figures 1 to 4 each show an embodiment of the first invention, in which Figure 1 is a sectional view thereof, Figure 2 is a plan view thereof,
Fig. 3 is a schematic diagram of application to formats, and Fig. 4 is a diagram showing trends in swirl ratio and volumetric efficiency. 5 and 6 show an embodiment of the second invention, respectively. FIG. 5 is a schematic diagram thereof, FIG. 6 is a diagram showing the tendency of swirl ratio and volumetric efficiency, and FIG. 7 and FIG. FIG. 8 is a diagram showing trends in swirl ratio and volumetric efficiency in each of the other examples of the present invention. FIG. 9 is a diagram further showing the tendency of swirling in another embodiment of the present invention. In the figure: 30... cylinder chamber, 20... spiral part. Pl...Intake boat, 11...Intake valve. Ao... Valve stem, co Yukiso Boa Nakano L> Applicant Toyota Central Research Institute Co., Ltd. Agent Patent attorney Yoshiyoshi Takahashi Yasushi Takahiro 2 persons o-26 Figure 8 Figure 9

Claims (1)

[Scope of Claims] (1) Consisting of an introduction part through which intake air flows, and a swirl part that communicates with the introduction part to form a section at the entire center of the valve shaft of the intake valve and communicates with the cylinder chamber, it causes a complete vortex flow in the intake air. An intake boat for an internal combustion engine is provided in a cylinder head of the internal combustion engine, and is configured by a curved line centered on the entire center of the helical axis on at least two lines of the helical passageway of the spiral part,
Let θ be the vertical angle of the valve shaft of the intake valve with respect to a line connecting the centers of the diameters of the plurality of cylinder chambers. An intake boat for an internal combustion engine, characterized in that the intake boat is arranged at a relative position of -45° and θ45°. (2) An intake boat metal internal combustion engine that is composed of an introduction part through which intake air flows, and a vortex part that communicates with the introduction part to form a section as the entire center of the valve shaft of the intake valve and communicates with the cylinder chamber to create a vortex in the intake air. Aligning with an intake boat of an internal combustion engine, which is provided in the cylinder head, and in which the spiral passage of the spiral portion is formed by a curved line having the entire center of the helical axis on at least two lines,
An internal combustion engine characterized in that, where γ is the distance from the center of the cylinder chamber diameter to the valve stem, and D is the cylinder chamber diameter, the ratio of the two is in a range that satisfies the relationship 0 ≦ r/D ≦ 0.25. intake boat. (3) Distance 111 from the center of the cylinder chamber diameter to the valve stem
! If f-γ is the cylinder chamber diameter in, the ratio of the two is in a range satisfying the relationship 0, γ/D≦0.25. Internal combustion engine intake boat. (4) When the seat diameter fd of the intake valve is taken as the entire diameter of the cylinder chamber, the ratio of the two is in a range satisfying the relationship of 0.68 ≦ d/D ≦ 0.44. the law of nature
2. An intake boat for an internal combustion engine according to claim 1. (5) The stroke of the piston that reciprocates in the axial direction in the cylinder chamber is 8, and the cylinder chamber diameter is D.
If so. An intake boat for an internal combustion engine according to claim 1, wherein the ratio of the two is in a range satisfying the relation: 1.0≦S/D 1.2. (6) Seat diameter y of the intake valve. d. The intake boat for an internal combustion engine according to claim 2, wherein the ratio of both is in a range satisfying the relationship: d/D≦0.44, where D is the total diameter of the cylinder chamber. . (7) Let the stroke of the piston reciprocating in the axial direction in the cylinder chamber be is, and the cylinder chamber diameter tD
If so. The intake boat for an internal combustion engine according to claim 2, wherein the ratio of the two satisfies the relationship of 1.0≦S/D≦1.2. (8) Let the seat diameter of the intake valve be fd. Cylinder chamber diameter total D
The intake boat for an internal combustion engine according to claim 6, wherein the ratio of the two satisfies the relationship: 0.68 d/f)≦α44. (9) Let the stroke is of the piston reciprocating in the axial direction within the cylinder chamber. Cylinder chamber diameter is D
The intake boat for an internal combustion engine according to claim 3, wherein the ratio between the two is in a range satisfying the relationship 1.0≦S/D 1.2. 00 The total stroke of the piston reciprocating in the axial direction within the cylinder chamber is 8. When the cylinder chamber diameter is D, the intake air of the internal combustion engine according to claim 8 is characterized in that the ratio thereof is in a range satisfying the relationship of 1.0 (8/D (1.2). boat.