JP3523545B2 - Engine swirl intake port - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swirl type intake port used for various engines such as a direct injection diesel engine / gasoline engine or a gas engine.

[0002]

[Prerequisite Configuration] The swirl type intake port of the engine of the present invention is, for example, as shown in FIGS.
As shown in (Prior Art), a device having the following preconditions is targeted.

FIG. 1 shows an embodiment of the swirl type intake port of the engine of the present invention. 1A is a cross-sectional plan view of the swirl type intake port, FIG. 1B is a vertical sectional side view thereof, and FIG. 1C is a vertical sectional front view thereof. 2 (A) is a cross-sectional plan view of the swirl type intake port of FIG. 1, FIG. 2 (B) -FIG.
2G is a cross-sectional view taken along the line BB to GG in FIG. FIG. 3 is a perspective view of the swirl type intake port of FIG. 9 is a perspective view of a swirl type intake port showing a conventional technique, and FIG. 10 is a vertical side view of FIG.

The port inlet (2) of the swirl type intake port (1) of the engine is connected to the port upstream part (3) and the port midstream part (4).
-, And it connects to a valve opening (6) through a port downstream part (5) in order. The downstream portion (5) of the port is swung from the proximal end portion (7) toward the distal end portion (8) along the circumferential direction around the valve opening axis (9) of the valve opening (6). Shape it. The tip portion (8) of the port downstream portion (5) is the base end portion of the port downstream portion (5).
A partition wall (10) is used to partition (7) .

In the closed state in which the valve port (6) is closed by the intake valve (23), from the tip portion (8) of the port downstream portion (5) to the base end portion (7) of the port downstream portion (5). A ventilation gap (24) for maintaining the intake swirl that allows the intake air to flow is provided at the lower end edge of the partition wall (10).
It is formed between (25) and the intake valve (23).

[Advantages of Assumption] The mixing performance of intake air and fuel is improved. In the intake stroke of the engine, the intake air flowing in the swirl type intake port (1) is swirled in the port downstream portion (5) and causes a strong swirl in the cylinder chamber (31). Therefore, the mixing performance of the intake air and the fuel is enhanced, and the combustion performance is enhanced.

[0007]. Turbulence due to interference of intake air in the downstream part of the port (5) disappears. If the intake air flowing in the port downstream portion (5) flows from the distal end portion (8) of the port downstream portion (5) to the proximal end portion (7), the intermediate port portion (4) of the port downstream portion (5) The intake air flowing from the tip (8) interferes with the intake air flowing into (5) to generate a turbulent flow, which reduces the intake flow velocity and volume efficiency to reduce the engine output. .

In the above premise, the intake air that has reached the tip portion (8) of the port downstream portion (5) is partitioned by the partition wall (10) to the base end portion (7) of the port downstream portion (5). Does not flow. Therefore, the "turbulent flow due to the interference of intake air in the port downstream portion (5)" is eliminated, the swirl force is strengthened, and the volumetric efficiency is enhanced.

[0009]. The swirl flow in the downstream portion (5) of the swirl begins to swirl early in the cylinder chamber (31) as much as the swirl flow immediately flows into the cylinder chamber (31) immediately after the intake valve (23) is opened, and swirls. Strength is strengthened. The intake air that has flowed to the port downstream portion (5) before the intake valve (23) is closed is the intake air from the tip portion (8) of the port downstream portion (5) after the intake valve (23) is closed. Ventilation gap for maintaining swirl (24)
Flow through to the base end (7) and the port downstream (5)
Keep turning inside.

Therefore, the intake air that continues to swirl in the downstream portion (5) of the port, when the intake valve (23) opens, is swirled by the swirling flow from the valve port (6) to the cylinder chamber (31). The swirl force is strengthened because the swirl force begins to turn swiftly in the cylinder chamber (31) early as much as it flows inward.

[0011]

2. Description of the Related Art The following prior art has the above-mentioned prerequisite structure. ○ Conventional technology. See Figures 9-10 (Japanese Patent Publication No. 2-31).
No. 776) FIG. 9 is a perspective view of a swirl type intake port showing a conventional technique,
FIG. 10 is a vertical side view of FIG.

The lower end edge (25) of the partition wall (10) is formed in a horizontal straight line and is orthogonal to the vertical valve opening axis (9) in a side view.

[0013]

The above-mentioned prior art has the following problems. (I). A part of the inward air flow (37) falls from the lower edge of the partition wall (25) to the lower side and becomes the reverse swirl flow (38), so that the motion inertia of the air intake is reduced and the volumetric efficiency is reduced. To do.

As shown in FIG. 5, a swirl type intake port
The intake air (36) flowing in (1) flows obliquely downward from the port midstream portion (4) toward the port downstream portion (5). Figure 5
In the prior art shown in (B), the lower end edge (25) of the partition wall (10) is formed horizontally. A part of the inward air intake flow (37) (see FIG. 4 (A)) flowing diagonally downward falls from the lower end edge (25) of the horizontal partition wall to the lower side thereof, and the reverse shown in FIG. 4 (A). It becomes a swirl component (38), friction and interference with the positive swirl flow (39), the motion inertia of the intake air is reduced, and the volumetric efficiency is reduced.

(B). The intake valve (23) is closed because the passage cross-sectional area of the intake swirl maintaining ventilation gap (24) in the port downstream part (5) cannot be larger in the peripheral part than in the center part of the port downstream part (5). At this time, the momentum of the intake swirl flow in the downstream portion (5) of the port cannot be increased, and the swirl ratio cannot be improved.

As shown in FIG. 5 (B), since the lower edge (25) of the partition wall (10) is formed in a horizontal line, the ventilation gap (24) for maintaining the intake swirl in the downstream portion (5) of the port is formed. The passage cross-sectional area of () cannot be larger in the peripheral portion than in the central portion of the port downstream portion (5). For this reason, during the valve closing period from the closing of the intake valve (23) to the opening of the intake valve (23), the swirl flow of intake air in the port downstream portion (5) cannot be strengthened.

As a result, the intake swirl flow in the port downstream portion (5) which is closed can only increase the speed at which it cannot flow into the cylinder chamber (31) immediately after the intake valve (23) begins to open. However, the swirl ratio in the cylinder chamber (31) cannot be improved, and the mixing performance of air and fuel cannot be improved to improve the combustion performance.

An object of the present invention is to do the following. (I). A part of the inward intake air flow falls downward from the lower edge of the partition wall and becomes the reverse swirl flow (38), and the amount of the inverse swirl flow (38) is reduced, thereby increasing the motion inertia of the intake air and improving the volumetric efficiency. (B). The intake swirl flow in the downstream portion of the port when the intake valve is closed is increased by making the passage cross-sectional area of the intake swirl maintaining ventilation gap in the downstream portion of the port larger in the peripheral portion than in the central portion of the downstream portion of the port. Strengthen the momentum and improve the swirl ratio.

(C). Sufficiently holds the swirl component of the intake air, while maintaining a strong swirl force of the intake air, increases the direct component of the intake air to increase volume efficiency. (D). The ventilation efficiency of the inward / inward intake air flowing through the inward / inward port portion of the intake port is reduced to further improve the volumetric efficiency. (E). It accelerates the direct component of intake air and strengthens the swirl force in the cylinder chamber.

[0020]

The swirl type intake port of the engine according to the present invention has the above-mentioned preconditions, and in order to solve the above-mentioned problems, for example, Figs. 1 to 3 and 8 (A).
As shown in (E), it is characterized in that the following characteristic configuration is added.

FIG. 1 shows an embodiment of the swirl type intake port of the engine of the present invention. 1A is a cross-sectional plan view of the swirl type intake port, FIG. 1B is a vertical sectional side view thereof, and FIG. 1C is a vertical sectional front view thereof. 2 (A) is a cross-sectional plan view of the swirl type intake port of FIG. 1, FIG. 2 (B) -FIG.
2G is a cross-sectional view taken along the line BB to GG in FIG. FIG. 3 is a perspective view of the swirl type intake port of FIG. 8 (A) to 8 (E) show various shapes of the partition wall according to the embodiment of the present invention or the modification thereof.

Invention 1 Claim 1. Figure 1 (A)
See FIGS. 3 and 8 (A)-(E). Of the lower end edge (25) of the partition wall (10), the lower end on the tip side of the valve opening (6) close to the valve opening axis (9). Connect the rim (26) to the valve mouth (6)
From the center of the valve opening
It is characterized in that the lower edge portion (27) on the base end side farther from (9) is formed by being displaced to the side farther from the valve opening (6).

Invention 2. Claim 2. Figure 1 (A)
See FIG. 3 and FIG. 8 (A)-(D). In Invention 1, the following configuration is added. The partition wall
The lower end edge (25) of the (10) is characterized in that it is formed in the form of one continuous inclined line. For example, the straight line shape shown in FIG. 8 (A), the gentle concave curve shape shown in FIG. 8 (B), the gentle convex curve shape shown in FIG. 8 (C), or the gentle S shape shown in FIG. 8 (D). It can be considered to form a curved line.

○ Invention 3. Claim 3. Figure 1 (A)
See FIG. 3 and FIG. 8 (A). In the above invention 1 or invention 2, the following configuration is added. The lower end edge (25) of the partition wall (10) is the port midstream portion (4) of the port lower surface (17) of the swirl type intake port (1).
It is characterized in that it is formed in a straight line substantially parallel to the lower surface part (28) of the port midstream part in a side view.

Invention 4. Claim 4. See FIGS. 1 and 3. In the above invention 1, invention 2, or invention 3, the following configuration is added. Of the opening cross-sectional area of the port inlet (2),
The opening inner surface edge (11) located on the inner side of the swirl type intake port (1) and the inlet lower edge (12) located on the valve opening (6) side are provided with an opening surface portion (13). Inner and lower opening area (13)
The opening surface portion (14) located on the opposite side of the inner-lower opening area (13) will be called the outer-up opening area (14).

In this case, the inner lower opening area
An imaginary straight line (16) connecting at least a part of (13) and a part of the valve mouth (6) extends over the entire length of the port upstream part (3), in the port midstream part (4), and in the port downstream. A port upstream part (3), a port midstream part (4), and a port downstream part (5) are formed so as to enter the part (5).

Invention 5. Claim 5. See FIG. 2 and FIG. In the above Invention 4, the following configuration is added. The port lower surface (17) of the swirl type intake port (1) is a port inlet.
As it goes from (2) through the port upstream part (3) to the port midstream part (4), the inner circumference side edge (19) becomes gradually lower than the outer circumference side edge (18). It is formed.

○ Invention 6. Claim 6. In the above Invention 4 or Invention 5, the following configuration is added. Inner side surface (20) of the swirl type intake port (1)
Is gradually displaced inward from the upper edge (21) of the lower edge (22) of the upper edge (21) as it goes from the port inlet (2) to the port upstream (3) to the port midstream (4). It is characterized in that it is formed in an inclined shape.

Invention 7. Claim 7. In the above Invention 4, Invention 5, or Invention 6, the following configuration is added. Port inlet of the swirl type intake port (1)
The shape of the port from (2) to the base end part (7) of the port downstream part (5) through the port upstream part (3) and the port midstream part (4) in this order is the port downstream part (5). ) Is formed in a curved shape in a direction opposite to the turning direction.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a swirl type intake port of an engine of the present invention will be described below with reference to FIGS.

FIG. 1 shows Embodiment 1 of the swirl type intake port of the engine of the present invention. 1 (A) is a cross-sectional plan view of the swirl type intake port, FIG. 1 (B) is a longitudinal side view thereof,
FIG. 1C is a vertical sectional front view thereof. 2 (A) is shown in FIG.
2B is a cross-sectional plan view of the swirl-type intake port of FIG. 2, and FIG. 2B is a cross-sectional view taken along the line BB of FIG. FIG. 3 is a perspective view of the swirl type intake port of FIG.

FIG. 4 is a diagram schematically showing the flow of intake air in a cross-sectional plan view of the swirl type intake port of FIG. 1 (A),
FIG. 4A is a cross-sectional view at a position slightly lower than that of FIG. 1A, and FIG. 4B is a cross-sectional view at the same height position as that of FIG. FIG. 5 (A) is an enlarged view of the V portion of FIG. 1 (B) and schematically shows the flow of intake air. 6 is a perspective view of the swirl-type intake port in FIG. 3 schematically showing the flow of intake air. Figure 7
FIG. 2 is a diagram schematically showing the flow of intake air in the cross-sectional plan view of the swirl type intake port of FIG. 1 (A).

A swirl type intake port (1) is formed in a cylinder head (41) of a direct fuel injection type vertical diesel engine. The port inlet (2) at the start end of the swirl type intake port (1) opens to the lateral side surface of the cylinder head (41), and the valve port (6) at the end thereof opens to the lower surface of the cylinder head (41). . Port inlet of swirl type intake port (1)
(2) is communicated with the valve port (6) through the port upstream part (3), the port midstream part (4), and the port downstream part (5) in this order.

The port downstream portion (5) extends from the base end portion (7) toward the tip end portion (8) along the circumferential direction around the valve opening axis (9) of the valve opening (6). I will turn. Port downstream
The upper surface (42) of (5) is formed in a continuous curved shape that continuously and smoothly descends over the entire length from the base end portion (7) to the tip end portion (8). Tip of the port downstream portion (5) (8) port downstream portion base end portion (5) with respect to (7), Subdivision in the partition wall (10)
Draw.

In the closed state where the valve port (6) is closed by the intake valve (23), from the tip portion (8) of the port downstream portion (5) to the base end portion (7) of the port downstream portion (5). A ventilation gap (24) for maintaining the intake swirl that allows the intake air to flow is provided at the lower end edge of the partition wall (10).
It is formed between (25) and the intake valve (23).

The valve opening of the lower edge (25) of the partition wall (10)
The lower end edge portion (26) on the tip side on the side close to the valve opening axis (9) of (6)
Is formed on the side closer to the valve opening (6), while the lower edge portion on the base end side (27) far from the valve opening axis (9) is
It is formed by displacing to the side far from the valve opening (6).

The lower end edge (25) of the partition wall (10) is formed in the shape of one continuous inclined line. Further, the lower edge (25) of the partition wall (10) is connected to the lower surface (1) of the swirl type intake port (1).
Portion of the middle part of the port (4) of 7)
It is formed in a straight line that is substantially parallel to (28) in a side view.

The swirl-type intake port (1) has a quadrilateral basic cross-sectional shape, and its corners are arcuate. The port entrance (2) has a square shape with rounded corners.

Of the opening cross-sectional area of the port inlet (2),
The opening inner surface edge (11) located on the inner side of the swirl type intake port (1) and the inlet lower edge (12) located on the valve opening (6) side are provided with an opening surface portion (13). , The inner bottom opening area (1
I will call it 3). The opening surface portion (14) located on the opposite side of the inner lower opening area (13) is replaced with the outer upper opening area (14).
Call. The inner lower opening area (13) and the outer upper opening area
An opening surface portion (15) between the opening (14) and the portion (14) will be referred to as a central opening region (15).

An imaginary straight line (16) connecting a part or all of the inner-lower-side opening region (13) and a part of the valve opening (6) is provided along the entire length thereof in the port upstream part (3) and the port. The upstream part of the port so that it enters into the middle part (4) and the downstream part of the port (5).
(3) Form the port midstream part (4) and the port downstream part (5). The lower surface of the swirl type intake port (1) (1
As 7) progresses from the port inlet (2) through the port upstream part (3) to the port midstream part (4), the inner circumference side edge (19) is gradually lower than the outer circumference side edge (18). It is formed into an inclined shape.

The inner side surface (20) of the swirl type intake port (1) advances from the port inlet (2) through the port upstream part (3) to the port midstream part (4), and its upper edge (21) ), The lower edge (22) is formed in an inclined shape that gradually displaces toward the inner side.

From the port inlet (2) of the swirl type intake port (1) to the port upstream part (3) and the port midstream part (4).
The shape of the port until the base end portion (7) of the port downstream portion (5) is formed in a curved shape in the direction reverse to the turning direction of the port downstream portion (5). is there. Figure 1
Reference numeral (30) is a cylinder, (43) is a piston, and (44) is a combustion chamber.

[Modification of Embodiment of the Invention] In the embodiment of the present invention described above, the lower edge (25) of the partition wall (10).
As a modified example of FIG. 8B, the shape of FIG.
It is conceivable to change the shape to any one of (E).

In FIG. 8B, the lower end edge (25) of the partition wall is formed in a gentle concave curve. In FIG. 8C, the lower end edge (25) of the partition wall is formed in a gentle convex curve. In FIG. 8D, the lower end edge (25) of the partition wall is formed in a gentle S-shaped curve. In FIG. 8D, the lower end edge (25) of the partition wall is bent and formed in a step shape.

[0045]

The swirl type intake port of the engine of the present invention has the following effects. ○ Invention 1. Claim 1. FIG. 1 (B), FIG. 3 to FIG.
See (A) and FIG. 8 (A)-(E). [ I. A part of the inward air flow (37) drops downward from the lower edge (25) of the partition wall and becomes the reverse swirl flow (38). To do. ]

As shown in FIG. 5, the swirl type intake port
The intake air (36) flowing in (1) flows obliquely downward from the port midstream portion (4) toward the port downstream portion (5). Figure 5
In the prior art shown in (B), the lower end edge (25) of the partition wall (10) is formed horizontally. A part of the inward air intake flow (37) (see FIG. 4 (A)) flowing diagonally downward falls from the lower end edge (25) of the horizontal partition wall to the lower side thereof, and the reverse shown in FIG. 4 (A). It becomes a swirl component (38), friction and interference with the positive swirl flow (39), the motion inertia of the intake air is reduced, and the volumetric efficiency is reduced.

In the present invention, as illustrated in FIGS. 8 (A) to 8 (E), the valve opening in the lower end edge (25) of the partition wall (10).
On the side close to the valve opening axis (9) of (6), the tip side lower edge part (26)
Is formed on the side closer to the valve opening (6), while the lower edge portion on the base end side (27) far from the valve opening axis (9) is
It is formed by displacing to the side far from the valve opening (6).

From this structure, as illustrated in FIG. 5A, the inward intake air flow (37) flowing obliquely downward (FIG. 4).
A part of (see (A)) falls from the lower end edge (25) of the horizontal partition wall to the lower side thereof and becomes an inverse swirl component (38) as compared with the case of the conventional technique shown in FIG. 5 (B). In comparison, it is significantly less. The amount of this reverse swirl flow (38) is significantly reduced, so friction and interference with the positive swirl flow (39) are reduced, the motion inertia of intake air is increased, and volume efficiency is improved.
It is possible to contribute to an increase in engine output and an improvement in combustion performance due to air richness.

[B. The intake valve (23) has a larger passage cross-sectional area of the intake clearance maintaining ventilation gap (24) in the downstream portion of the port (5) in the peripheral portion than in the central portion of the downstream portion (5).
When the valve is closed, the momentum of the intake swirl flow in the downstream portion (5) of the port is increased, and the swirl ratio is improved. ]

As illustrated in FIG. 5A, the partition wall (10)
The lower end edge portion (26) of the lower end edge (25) of the valve is formed so as to be positioned closer to the valve opening (6), while the lower end edge portion of the base end side is formed.
It was formed by displacing (27) to the side far from the valve opening (6).

With this structure, the passage cross-sectional area of the intake swirl maintaining ventilation gap (24) at the port downstream portion (5) is
During the valve closing period from when the intake valve (23) is closed to when the intake valve (23) is closed by the amount that the peripheral part is larger than the central part (5),
The momentum of the swirling flow of the intake air in the port downstream portion (5) becomes stronger.

As a result, the intake swirl flow in the downstream portion (5) of the closed port is swiftly and vigorously flowing into the cylinder chamber (31) immediately after the intake valve (23) begins to open. The swirl ratio in the chamber (31) is improved, the mixing performance of air and fuel is improved, and the combustion performance is improved.

Invention 2. Claim 2. Figure 1 (B)
See FIG. 3, FIG. 5 (A), and FIG. 8 (A)-(D). The invention 2 has the following effects in addition to the effects [a] and [b] of the invention 1. [C. The amount of the inward intake air flow (37) falling from the lower edge (25) of the partition wall and becoming the inverse swirl component (38) is further reduced, and the above effect [A. Volume efficiency is improved]. ]

As illustrated in FIGS. 8 (A)-(D), the lower end edge (25) of the partition wall (10) is formed as one continuous inclined line. From this configuration, as compared with the case where the partition wall lower end edge (25) illustrated in FIG. 8 (E) is bent stepwise,
It is excellent in the following points. A part of the inward intake air flow (37) falls downward from the lower end edge (25) of the partition wall to become an inverse swirl component, and the amount is further reduced, and the above effect [A. Volume efficiency is improved].

Invention 3. Claim 3. Figure 1 (B)
See FIG. 3, FIG. 5 (A), and FIG. 8 (A). The invention 3 has the following effect in addition to the effects [a] and [b] of the invention 1. [D. The amount of the inward intake air flow (37) falling from the lower edge (25) of the partition wall to form the inverse swirl component (38) is minimized, and the above effect [A. The volume efficiency is improved]. ]

The lower end edge (25) of the partition wall (10) is located on the lower surface portion (28) of the middle port portion (4) of the swirl type intake port (1). On the other hand, it was formed into a substantially parallel straight line in a side view. From this configuration, FIG.
It is excellent in the following points as compared with the case where the lower end edge (25) of the partition wall illustrated in (B)-(D) is curved.

Intake flowing through the swirl type intake port (1)
(36) flows into the port downstream portion (5) from the port midstream portion (4), and flows substantially parallel to the port midstream portion lower surface portion (28) as illustrated in FIG. 5 (A). Therefore, the amount of the inward air flow (37) falling from the lower edge (25) of the partition wall to become the inverse swirl component (38) is minimized, and the above effect [A. The volume efficiency is improved].

Invention 4. Claim 4. 1 and 3
See FIGS. 6 and 7. The invention 4 has the following effect in addition to the effects [a] and [b] of the invention 1. [E. Sufficiently holds the swirl component of the intake air, while maintaining a strong swirl force of the intake air, increases the direct component of the intake air to increase volume efficiency. ]

The flow of intake air in the swirl type intake port (1) is schematically shown in FIGS. 6 and 7. In this schematic diagram,
The intake flow that has entered from the outside upper opening region (14) of the port inlet (2) is called the outside upper intake flow (34). Central opening area (15)
The inspiratory flow entering from is called the central part inspiratory flow (35). Then, the intake air flow entering from the opening region (13) toward the inside and below is referred to as the intake flow (33) toward and below the inside.

The outward intake air flow (34) is directed to the port upstream portion (3).
・ Majorly wrap around the outer upper space inside the port midstream part (4) and the port downstream part (5), and pass through the valve port (6) from the downstream side region part of the port downstream part (5) to the cylinder chamber (31 ) Flows in as a strong swirl component.

The central part intake flow (35) is the above-mentioned outside intake flow.
At a position slightly closer to the center than (34), inside the port upstream part (3), the port midstream part (4) and the port downstream part (5), gradually shifting to the outer space part side from the center part space part. As it flows, it flows from the upstream region of the port downstream portion (5) through the valve port (6) into the cylinder chamber (31) as a swirl component. Thereby, the swirl component of the intake air flowing into the cylinder chamber (31) is sufficiently retained, the swirl force of the intake air is strongly maintained, and the mixing performance of air and fuel is maintained high.

Moreover, the inward-inward-inflow flow (33) is located further inward-downward of the central intake flow (35) and is located at the port upstream part (3), the port midstream part (4) and the port downstream part (5). It flows along the inner lower space portion of the inside, flows straight from the upstream area portion of the port downstream portion (5), through the valve port (6), into the cylinder chamber (31) as a direct component and vigorously.

As a structure for this purpose, a virtual straight line (16) connecting at least a part of the inner-lower-side opening region (13) and a part of the valve opening (6) is provided over the entire length of the port upstream part ( 3)
The port upstream part (3), the port midstream part (4), and the port downstream part (5) are formed so as to enter the inside of the port middle part (4) and the inside of the port downstream part (5).

From this configuration, the intake air flow (33) that is close to the inside and below
Is the imaginary straight line (1) at the inner space below the port upstream part (3), the port midstream part (4) and the port downstream part (5).
Passing straight along almost 6), passing from the upstream region of the port downstream portion (5) through the valve port (6), it goes straight into the cylinder chamber (31) and flows as a direct component.

For this reason, the inwardly downward intake air flow (33) has a small degree of bending and has a high straightness, and the direct component of the intake air comprising the inwardly downward intake air flow (33) has strong momentum and a high flow velocity. Since the flow rate is large, the volumetric efficiency is greatly increased. As a result, the output of the engine can be effectively increased.

Invention 5. Claim 5. 2 and 3
See FIGS. 6 and 7. The invention 5 has the following effect in addition to the effect [a] and [b] of the invention 1 and the effect [e] of the invention 4. [ What. The ventilation resistance of the intake air flow (33) inward and downward is reduced, and the volumetric efficiency is further enhanced. ]

As the port lower surface (17) of the swirl type intake port (1) advances from the port inlet (2) to the port upstream part (3) to the port midstream part (4), its outer side edge ( 18)
On the other hand, the inner side edge (19) was formed in an inclined shape in which it gradually became lower.

From this structure, first, the inner circumference side edge (19)
In the passage portion where the opening area (13) at the inner bottom of the port inlet (2) and the valve opening (6) communicate with each other linearly along the imaginary straight line (16) as the Large passage cross-sectional area can be obtained. Next, the inward intake air flow (33) approaches the inner side edge (19) side by the amount that the inner side edge (19) is formed in an inclined shape that gradually decreases, and the valve opening ( It becomes easy to flow into the cylinder chamber (31) from a portion closer to the valve opening axis (6) of 6).

Then, the inward flow toward the inner and lower sides (3
3) becomes closer to a straight line over the entire length of the channel. Due to these three combined actions, the ventilation resistance of the inward-lower intake air flow (33) becomes smaller and the momentum of the flow becomes stronger, so that the flow rate of the direct component due to the inward-lower intake air flow (33) further increases. Volume efficiency is increased accordingly.

Invention 6. Claim 6. 2 and 3
See FIGS. 6 and 7. The invention 6 has the following effects in addition to the effects [a] and [b] of the invention 1 and the effect [e] of the invention 4. [To. The ventilation resistance of the inwardly lower intake air flow (33) is reduced, and the volumetric efficiency is further enhanced. ]

The inner side surface (20) of the swirl type intake port (1) advances from the port inlet (2) through the port upstream part (3) to the port midstream part (4) and its upper edge (21). ), The lower side edge (22) is formed in an inclined shape gradually displacing toward the inner side.

With this structure, the inner lower opening area (13) of the port inlet (2) and the valve opening (6) are reduced by the amount that the lower edge (22) of the port is gradually displaced inward. A large passage cross-sectional area can be obtained in the passage portion that linearly communicates along the virtual straight line (16). Next, the intake flow (33) that is closer to the inner and lower sides is formed by the amount that the lower edge (22) of the lower edge (22) is gradually displaced inward.
However, it becomes easier to flow into the cylinder chamber (31) from a portion closer to the valve opening axis (9) of the valve opening (6) and closer to the valve opening axis (9) of the valve opening (6).

Then, the inwardly downward intake air flow (33) becomes closer to the straight line over the entire length of the flow passage by the amount that the lower edge (22) is formed in an inclined shape that is gradually displaced inward. .
Due to these three combined actions, the ventilation resistance of the inward-lower intake air flow (33) becomes smaller, and the momentum of the flow becomes stronger, so that the flow rate of the direct component by the inward-lower intake air flow (33) further increases. As a result, the volumetric efficiency is increased and the output of the engine can be further improved.

Invention 7. Claim 7. Figure 1 (A)
See FIGS. 3, 6 and 7. The invention 7 has the following effect in addition to the effect [a] and [b] of the invention 1 and the effect [e] of the invention 4. [Chi. Accelerate the direct component of the intake air (33) to strengthen the swirl force. ]

From the port inlet (2) of the swirl type intake port (1) to the port upstream part (3) and the port midstream part (4).
The shape of the port until the base end portion (7) of the downstream portion (5) of the port is formed in a curved shape that is reversed with respect to the turning direction of the downstream portion (5) of the port.

With this structure, the inward-downward intake air flow (33) as a direct component of intake air is accelerated while being strongly pressed against the inner side surface (20) as it goes forward in the intake port, and the cylinder chamber The flow velocity in (31) is increased, the swirl force is strengthened, the mixing performance of air and fuel is improved, and it is possible to contribute to improved output and reduced fuel consumption.

[Brief description of drawings]

FIG. 1 shows Embodiment 1 of the swirl type intake port of the engine of the present invention. 1A is a transverse plan view of the swirl type intake port, FIG. 1B is a vertical side view of FIG. 1A, and FIG. 1C is a vertical front view of FIG. 1A.

FIG. 2 is a sectional view of each part of the swirl type intake port of FIG. FIG. 2A is a cross-sectional plan view of the swirl type intake port of FIG. 1. FIG. 2B is a sectional view taken along line BB of FIG. FIG. 2C is a cross-sectional view taken along the line CC of FIG. Figure 2
2D is a cross-sectional view taken along the line DD of FIG. FIG. 2E is a cross-sectional view taken along the line EE of FIG. FIG. 2F is a sectional view taken along line FF of FIG. FIG. 2G is a sectional view taken along the line GG of FIG.

3 is a perspective view of the swirl type intake port of FIG. 1. FIG.

FIG. 4 is a diagram schematically showing the flow of intake air in a cross-sectional plan view of the swirl type intake port of FIG. 1 (A). FIG. 4A shows FIG.
(A) Transverse plan view at a position slightly lower than (A). FIG. 4B is a cross-sectional plan view at the same height position as FIG.

FIG. 5 is a diagram schematically showing the flow of intake air by enlarging the V portion of FIG. 1 (B). FIG. 5A shows an embodiment of the present invention, and FIG. 5B shows a conventional technique.

6 is a diagram schematically showing the flow of intake air in the perspective view of the swirl type intake port in FIG.

FIG. 7 is a diagram schematically showing the flow of intake air in the cross-sectional plan view of the swirl type intake port in FIG. 1 (A).

FIG. 8 is an enlarged view of a V portion in FIG. 1B showing various shapes of partition walls. FIG. 8A shows an embodiment of the present invention. Figure 8
FIGS. 8B to 8E show modifications of FIG. 8A. FIG. 8F shows a conventional technique.

FIG. 9 is a perspective view of a swirl type intake port showing a conventional technique.

10 is a vertical side view of FIG.

[Explanation of symbols]

1 ... Swirl type intake port. 2 ... Port entrance. 3 ...
Port upstream. 4 ... Port middle section. 5 ... Port downstream section. 6 ... Valve mouth. 7 ... Base end. 8 ... Tip. 9 ... Valve stem axis. 10 ... Partition wall. 11 ... Inside edge of entrance. 12
… The lower edge of the entrance. 13 ... Inward opening area. 14 ... Outward opening area. 16 ... Virtual straight line. 17 ... Port bottom surface.
18 ... Outer side edge. 19 ... Inner side edge. 20 ... Inner side surface. 21 ... Upper edge. 22 ... Lower edge. 23 ...
Intake valve. 24 ... Ventilation gap for maintaining intake swirl. 25 ... Lower edge of partition wall. 26 ... Tip on the lower end edge side. 27 ... Lower edge portion on the base end side. 28 ... Lower part of middle part of port.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Wataru Iwanaga Inventor 3-8 No. 8 Chikko Shinmachi, Sakai City, Osaka Prefecture Kubota Sakai Seaside Factory (72) Inventor Shuichi Yamada 3-8 No. 3 Tsukiko Shinmachi, Sakai City, Osaka Prefecture Co., Ltd. Kubota Sakai Seaside Factory (72) Inventor Hideya Miyazaki 3-8 Chikko Shinmachi, Sakai City, Osaka Prefecture Kubota Sakai Seaside Factory (56) Reference JP-A-2-271031 (JP, A) JP-A-58 -62362 (JP, A) JP 58-28517 (JP, A) JP 48-73611 (JP, A) JP 58-144625 (JP, A) JP 59-94123 (JP, U) ) Actual development Sho 58-44436 (JP, U) Actual development Sho 56-161136 (JP, U) Japanese Patent Publication No. 2-31776 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) F02B 31/00

Claims (7)

(57) [Claims] 1. A swirl type intake port (1) of an engine, wherein a port inlet (2) is connected to a port upstream part (3) and a port midstream part.
(4) · and the port downstream part (5) are communicated with the valve port (6) in order, and the port downstream part (5) moves from the base end part (7) to the tip part (8) of the valve. The mouth (6) is swirled around the valve shaft center (9) along the circumferential direction, and the tip portion (8) of the port downstream portion (5) is the base end of the port downstream portion (5). In a closed state in which the partition wall (10) is partitioned from the part (7) and the valve opening (6) is closed by the intake valve (23),
The partition wall (10) is provided with an intake swirl maintaining ventilation gap (24) that allows intake air to flow from the tip portion (8) of the port downstream portion (5) to the base end portion (7) of the port downstream portion (5). Lower edge (25) and intake valve
In the swirl type intake port of the engine formed with (23), the valve opening axis of the valve opening (6) in the lower end edge (25) of the partition wall (10)
The lower end edge portion (26) on the side closer to (9) is formed by being positioned closer to the valve opening (6), while the axial center of the valve opening (9) is formed.
A swirl type intake port of an engine, characterized in that a lower end portion (27) of a base end on a side farther from is formed by displacing to a side farther from a valve opening (6). 2. The swirl type intake port of the engine according to claim 1, wherein the lower end edge (25) of the partition wall (10) is formed in a continuous inclined line shape. thing. 3. The swirl type intake port for an engine according to claim 2, wherein the lower end edge (25) of the partition wall (10) is a swirl type intake port.
It is characterized in that it is formed in a straight line substantially parallel to the lower surface part (28) of the middle part of the port (4) of the lower part (17) of the port of (1) in side view. . 4. The swirl type intake port of the engine according to claim 1, claim 2, or claim 3, wherein an inner circumference of the swirl type intake port (1) in the opening cross-sectional area of the port inlet (2). The inner edge of the entrance (11) located on the side,
The opening surface portion (13) located near the inlet lower edge (12) located on the valve opening (6) side is called an inner lower opening area (13), and the inner lower opening area (13) Opening surface part (1
In the case where 4) is referred to as the outer upper opening area (14), at least a part of the inner lower opening area (13) and the valve opening (6)
So that the virtual straight line (16) connecting with a part of the port enters the port upstream part (3), the port midstream part (4), and the port downstream part (5) over its entire length. (3) The midstream portion (4) of the port and the downstream portion (5) of the port are formed. 5. The swirl type intake port for an engine according to claim 4, wherein the port lower surface (17) of the swirl type intake port (1) passes through the port inlet (2) and the port upstream portion (3). Middle class
As it goes to (4), the inner peripheral side edge (19) is gradually lowered with respect to the outer peripheral side edge (18), and is formed in an inclined shape. 6. The swirl type intake port for an engine according to claim 4 or claim 5, wherein the inner side surface (20) of the swirl type intake port (1) extends from the port inlet (2) to the port upstream portion (3). ) Via the middle part of the port
As it goes to (4), the lower edge (22) of the upper edge (21) is formed so as to be gradually displaced inward toward the inner side. 7. The swirl type intake port of the engine according to claim 4, 5, or 6, wherein from the port inlet (2) of the swirl type intake port (1),
After going through the port upstream part (3) and the port midstream part (4) in order,
The port shape up to the base end portion (7) of the port downstream portion (5) is characterized in that it is formed in a curved shape that is reverse to the turning direction of the port downstream portion (5). thing.