JP7099950B2 - Intake manifold - Google Patents

Description

The present invention relates to an intake manifold installed on the intake side of a cylinder head in various engines such as industrial engines.

For example, it is known that the intake manifold applied to the engine includes a branched intake manifold disclosed in Patent Document 1 and a box-shaped intake manifold disclosed in Patent Document 2. ..

The branched intake manifold has a structure including a plurality of branched pipes corresponding to each intake port, a horizontally long intake manifold body portion connecting the roots of the branched pipes, and an air suction portion. The box-shaped intake manifold has a structure including an intake manifold body portion having one opening sized to cover a plurality of intake ports, and an air suction portion.

When the box-shaped intake manifold is applied to an industrial diesel engine, as disclosed in Patent Document 2, a fuel injection supply pump (or its pump housing) installed at the upper position on the lateral side of the cylinder block. However, it may interfere with the placement space of the intake manifold.

That is, as shown in FIGS. 1 and 2 (B) of Patent Document 2, most of the parts corresponding to the intake port of the first cylinder and the parts corresponding to the intake port of the second cylinder in the main body of the intake manifold. The depth of the corresponding part must be much narrower than the depth of the part corresponding to the intake port of the 3rd and 4th cylinders in order to avoid interference with the fuel injection supply pump arranged on the side. .. That is, the cross-sectional area of the internal space of the intake manifold body is a non-uniform (asymmetrical) and distorted intake manifold in which one end side in the longitudinal direction is smaller than the other end side.

The above-mentioned distorted intake manifold has a disadvantage that the amount of intake air at each intake port tends to differ. Therefore, the intake manifold is made of die-cast, which can be finished with high quality and precision and is suitable for mass production. It has also been tried, but not enough.

Jitsukaisho 59-139570 Gazette JP-A-2015-34526

An object of the present invention is to further devise the shape and structure of each part such as the intake manifold main body and the suction part so that air can be sent as uniformly as possible to a plurality of intake ports even though the intake manifold main body has a distorted shape. The point is to provide an intake manifold with better combustion efficiency.

The present invention is in the intake manifold.
An intake manifold main body having an internal space having one long opening covering a plurality of intake ports and a suction passage having a suction passage opening to the internal space in the middle portion in the longitudinal direction of the intake manifold main body are formed. And have
The cross-sectional area of the internal space in the direction orthogonal to the longitudinal direction is reduced at one end of the intake manifold main body in the longitudinal direction.
It is characterized in that a bypass path for communicating an intermediate portion in the air flow direction in the suction passage and the one end portion in the internal space is provided.

For example, the suction portion has a vertical passage portion extending in a direction intersecting the longitudinal direction and opening into the internal space, and a horizontal passage portion extending in a direction along the longitudinal direction and connecting to the vertical passage portion. , The bypass path may be communicated with the lateral passage portion. Further, it is convenient that the bypass path has a cross-sectional area smaller than the cross-sectional area of the suction passage.

Further, in the vertical passage portion, the rear portion of the vertical passage on the side of the main body of the in-mani and the front portion of the vertical passage on the side of the horizontal passage are removably connected, and the bypass path is connected to the in-mani. The rear part of the bypass on the side of the main body and the front part of the bypass on the side of the horizontal passage are removably connected, and the suction part is a suction rear part having the rear part of the vertical passage and the rear part of the bypass. It is preferable that the suction front portion having the vertical passage front portion, the bypass front portion, and the lateral passage portion is detachably connected to each other.

It is preferable that the position of the suction portion in the longitudinal direction with respect to the in-mani main body portion is set so that the suction passage is communicated with a portion other than the one end portion in the internal space. It is also possible to have the suction passage extending along the direction of the width intersecting both the longitudinal direction and the depth direction of the space.

Further, it is convenient that the suction portion is for an in-line 4-cylinder engine formed in the intake manifold main body portion at a position corresponding to the intake port of the second cylinder and the intake port of the third cylinder. The reduction in the cross-sectional area of the internal space at one end thereof may be due to narrowing the depth of the internal space with respect to the long opening.

According to the present invention, since the bypass path for communicating the intermediate portion in the air flow direction in the suction passage and one end portion in the internal space, that is, the portion where the cross-sectional area is reduced is provided, the cross-sectional area of the internal space is reduced. When air is flowing to the intake port corresponding to the specified location, air can efficiently flow from the bypass path, which is a shortcut, in addition to the normal intake passage, and the amount of intake air can be greatly increased.

When air is flowing through the intake port corresponding to the unreduced cross-sectional area in the internal space, the effect of the distant bypass path is negligible and is almost the same as the air flow from the normal intake passage. Become. In other words, the degree of increase in the amount of air due to the bypass path provided near the intake port where air is most difficult to enter becomes weaker as the intake port is farther from the bypass path. The amount of intake air) can be set so that there is almost no difference between them.

As a result, by further devising the shape and structure of each part such as the intake manifold body and suction part, it has been improved so that even though it has a distorted shape of the intake manifold body, air can be sent to multiple intake ports as uniformly as possible. Therefore, it is possible to provide an intake manifold having more excellent combustion efficiency.

Right side view of industrial diesel engine Top view of the engine shown in FIG. Front view of the engine shown in FIG. Right side view showing the intake manifold and suction duct Plan view of the main body of the intake manifold Left side view showing the intake manifold and suction duct with a partial notch

Hereinafter, an embodiment of the intake manifold (intake manifold of an engine) according to the present invention will be described when applied to an in-line 4-cylinder industrial diesel engine with reference to the drawings.

As shown in FIGS. 1 to 3, in an industrial diesel engine (hereinafter, simply abbreviated as an engine) E, a cylinder head 2 is assembled on a cylinder block 1, and a cylinder head cover (hereinafter, simply abbreviated as an engine) is placed on the cylinder head 2. Hereinafter, abbreviated as "head cover") 3 is assembled, and an oil pan 4 is assembled at the lower part of the cylinder block 1. The upper half of the cylinder block 1 is formed in the cylinder 1A, and the lower half is formed in the crankcase 1B.

A transmission case 5 is assembled on the front side of the cylinder block 1, and a drive pulley 6 driven by a crank shaft (not shown) is provided on the lower portion of the transmission case 5. A support hub 7A of a fan pulley (not shown) for driving an engine cooling fan 7 (see FIG. 1) is provided on the upper portion of the transmission case 5 in a state of having an axial center P in the front-rear direction. Although not shown, a belt (not shown) is provided over the driven pulley (not shown) of the drive pulley 6, the fan pulley, and other auxiliary equipment (alternator, etc.).

A flywheel housing 8 is assembled to the rear end of the cylinder block 1, and an exhaust manifold (not shown), a water flange 9 and the like are provided on the left side of the cylinder block 1. An oil filter 10, an intake manifold 11, a fuel injection supply pump 12, and the like are provided on the right side of the cylinder block 1. This engine E is configured as an in-line 4-cylinder engine in which four pistons (not shown) are lined up in front and rear in series. A suction duct 16 having a substantially J-shaped tubular shape is bolted to the intake manifold 11 in order to communicate with an intake system such as an air cleaner (not shown).

As shown in FIGS. 1 and 4 to 6, the intake manifold main body 11A in which the internal space 13 having one long opening 13A long in the front-rear direction is formed, and the longitudinal direction (front-back) of the intake manifold main body 11A. It is configured in a box shape having an air suction portion 11B formed in the middle portion of the direction). The long opening 13A is formed into an elongated opening that is long and short in the front-rear direction and has a size that covers four intake ports p1, p2, p3, and p4 arranged in series in the front-rear direction in the cylinder head 2. Has been done.

The intake manifold main body 11A is provided with an outer peripheral flange 11a having a plurality of bolt insertion holes (notation omitted), and the internal space 13 having the elongated opening 13A has a depth d in the longitudinal direction of the intake manifold main body 11A. It is set in a distorted shape that it is narrowed at the rear end (an example of one end) (in the front-back direction).

That is, as shown in FIG. 5, the internal space 13 is based on the normal space portion 13T whose depth d has a somewhat long (deep) normal depth d1, but the depth d at the front end portion is larger than the normal depth d1. It is set in the narrow space portion 13C having a remarkably narrow narrow depth d2 (d2 <d1). That is, in the internal space 13, the cross-sectional area in the front-rear direction or the left-right direction, which is a direction orthogonal to the front-rear direction, is smaller in the narrow space portion 13C than in the normal space portion 13T.

The portion of the narrow depth d2 (narrow space portion 13C) is a range of the narrow portion length L2 from the rear end of the internal space 13 having the total length (length) L, and the cross-section changing portion 17 having the inclined side wall 11b and the narrow portion length. The portion having the length obtained by subtracting L2 from the total length L is usually the portion having the depth d1. Considering that the cross-sectional change portion 17 is also a portion of the normal depth d1, the portion of the normal depth d1 (normal space portion 13T) in the internal space 13 is a length portion (L-L2) from the front end. That is, the intake manifold main body 11A includes an upper wall 11c and a lower wall 11d having uneven left and right widths, a normal side wall 11e (side wall F) , an inclined side wall 11b (side wall F) , and a narrow side wall 11f (side wall F) . The interior space 13 has a stepped shape in which the depth d differs depending on the portion.

Further, the dimensional relationship between the width of the internal space 13 (width of the long opening 13A) w and the normal depth d1 and the narrow depth d2 is set to d1> w> d2 (d1 = 1.2w, d2 = 0.4w). However, this is not the case. As an example, the dimensional relationship of 1.0w ≦ d1 ≦ 1.4w and 0.3w ≦ d2 ≦ 0.5w is applied. Further, regarding the length in the longitudinal direction of the internal space 13, the relationship of 0.25L ≦ L2 ≦ 0.35L is often set between the narrow portion length L2 and the total length L, but this is not limited to this. do not have.

As shown in FIGS. 4 to 6, the suction portion 11B has a suction case portion 14 and a suction flange 15, and a suction passage 14A is internally formed in the suction case portion 14 and is opened upward in the suction flange 15. An air inlet 14a and two bolt holes (notation omitted) are formed. The flange portion 16A of the suction duct 16 described above can be bolted to the upper side of the suction flange 15. The suction portion 11B has a suction passage 14A communicating with the internal space 13 in a state of opening in the width w direction (vertical direction) in the middle of the longitudinal direction of the in-mani main body portion 11A.

The suction portion 11B is above the normal space portion 13T, which is a portion having the normal depth d1 of the intake manifold main body portion 11A, in a state where the suction passage 14A is located slightly closer to the second intake port p2 of the third intake port p3 in the front-rear direction. It is formed in a protrusion. Of the four intake ports p1 to p4, the frontmost side is the intake port p1 of the first cylinder, and from there to the rear, the intake port p3 of the second cylinder, the intake port p3 of the third cylinder, and the intake of the fourth cylinder. It is lined up with port p4.

That is, the suction portion 11B is positioned in the longitudinal direction with respect to the in-mani main body portion 11A so that the suction passage 14A is communicated with a portion (normal space portion 13T) other than one end portion (narrow space portion 13C) in the internal space 13. , The position of the distance K from the rear end of the internal space 13 to the front (see FIG. 6)] is set. Then, the suction portion 11B provides a suction passage 14A extending along the width direction (the direction of the width w and the vertical direction) intersecting both the longitudinal direction (front-back direction) and the depth direction (horizontal direction) of the internal space 13. It is a configuration that has.

[Embodiment 1]
As shown in FIGS. 4 to 6, the intermediate portion (straight-moving portion 16C) in the air flow direction in the suction passage 14A and the portion (narrow space portion 13C) in the internal space 13 where the cross-sectional area is reduced are communicated with each other. A bypass path 26 is provided. The bypass passage 26 has a cross-sectional area smaller than the cross-sectional area of the suction passage 14A. The suction portion 11B has a vertical passage portion 28 extending in a direction (vertical direction) intersecting the longitudinal direction (front-back direction) and opening into the internal space 13, and a horizontal passage extending in a direction along the longitudinal direction and connecting to the vertical passage portion 28. The bypass road 26 has a portion 27 and is a vertically facing passage that communicates with the lateral passage portion 27.

In the vertical passage portion 28, the vertical passage rear portion 28B on the side of the intake manifold main body 11A and the vertical passage front portion 28A on the side of the horizontal passage portion 27 are detachably connected, and the bypass path 26 is the intake manifold main body. The bypass rear portion 26B on the side of the portion 11A and the bypass front portion 26A on the side of the lateral passage portion 27 are removably connected by bolting means. The suction portion 11B includes a suction rear portion 11D having a vertical passage rear portion 28B and a bypass rear portion 26B, and a suction front portion 11C having a vertical passage front portion 28A, a bypass front portion 26A, and a lateral passage portion 27 by bolting means. It is configured to be detachably connected.

As shown in FIGS. 4 and 6, the suction duct 16 has an elbow portion 16B continuous with the flange portion 16A, a straight portion 16C following the elbow portion 16B, and an inlet portion 16D, and the shape of the side view is substantially J. It has a character shape. The vertical passage front portion 28A and the horizontal passage portion 27 formed in the flange portion 16A, and the vertical passage rear portion 28B (of the intake manifold main body portion 11A) of the suction rear portion 11D are all suction passages 14A.

A bypass protrusion 29 having a bypass rear portion 26B is formed on the intake manifold main body portion 11A, and a mounting flange 29a is formed on the upper end of the bypass protrusion 29. A protruding flange 30 having a bypass front portion 26A is formed in the suction duct 16 (straight-moving portion 16C), and the protruding flange 30 and the mounting flange 29a are connected by bolting means. It is convenient if the height positions of the upper surface of the suction flange 15 and the upper surface of the protrusion flange 30 are the same (see FIG. 4).

That is, the intake manifold 11 includes a first manifold component (notation omitted) having an intake manifold main body portion 11A, a suction rear portion 11D, and a bypass rear portion 26B, a vertical passage front portion 28A, a horizontal passage portion 27 (suction duct 16), and a suction manifold portion 11. It is composed of a bolt connection of two parts with a second manifold part (notation omitted) having a bypass front portion 26A. Further, when the vertical passage portion 28 is used as a reference, the narrow space portion 13C having a narrow narrow depth d2 having a narrow depth d and the straight portion 16C to which the bypass path 26 is connected are arranged on the same direction side (front side). There is.

As described above, in the intake manifold 11, in addition to the vertical passage portion 28 which is the terminal portion in the air flow direction in the suction passage 14A of the suction portion 11B, the straight portion 16C and the in-mani which are the intermediate portions in the air flow direction. A bypass path 26 for short-circuiting the narrow space portion 13C of the main body portion 11A is provided. Therefore, when air is flowing to the intake port p1 of the first cylinder, air efficiently flows not only from the vertical passage portion 28 but also from the bypass path 26 which is a shortcut, and the intake air amount can be greatly increased. ..

When air is flowing through the intake port p4 of the fourth cylinder, the influence of the bypass path 26 far from the location is slight, and the air flow is almost from the vertical passage portion 28. That is, the degree of increase in the amount of air due to the bypass path 26 provided near the intake port p1 of the first cylinder is p1> p2> p3> p4, so that the amount of intake air in the plurality of intake ports p1 to p4 (unit time). The amount of intake air per hit) can be made almost unchanged.

Therefore, even if the intake manifold 11 has a distorted shape in which the cross-sectional area of the internal space 13 of the in-mani main body 11A becomes non-uniform in the longitudinal direction, such as having a normal space portion 13T and a narrow space portion 13C, the intake manifold 11 is cut off. The amount of intake air to the intake port located in a small area (narrow space 13C) can be increased reasonably. As a result, the amount of intake air to the plurality of intake ports can be made uniform as much as possible, and an intake manifold having excellent combustion efficiency can be provided. Further, as a result, it is possible to reduce the variation in the intake air amount between the cylinders even as a die-cast intake manifold.

[Another Embodiment]
(1) In the present embodiment, the intake manifold main body portion 11A and the suction portion 11B are formed by one component, although the structure is divided into two parts, the first and second manifold parts (notation omitted). It may be a manifold.
(2) The suction unit 11B can correspond to various shapes such as a linear one extending upward, a "<" shape, and an S-shaped curved one.

(3) The positions of the vertical passage portion 28 and the bypass path 26 with respect to the longitudinal direction of the intake manifold main body 11A vary depending on various conditions such as the number and position of intake ports, the shape of the intake manifold main body 11A, and the cross-sectional area of the internal space 13. Can be changed and set. The ratio of the cross-sectional area of the bypass path 26 to the cross-sectional area of the vertical passage portion 28 can also be appropriately changed and set.

11A Inmani body 11B Suction part 11C Suction front part 11D Suction rear part 13 Internal space 13A Long opening 14A Suction passage 26 Bypass road 26A Bypass front part 26B Bypass rear part 27 Horizontal passage part 28 Vertical passage part 28A Vertical passage front part 28B Vertical Rear of the aisle
F side wall
d Depth p1 to p4 Intake port

Claims (8)

An intake manifold main body having an internal space having one long opening covering a plurality of intake ports and a suction passage having a suction passage opening to the internal space in the middle portion in the longitudinal direction of the intake manifold main body are formed. And have
The cross-sectional area of the internal space in the direction orthogonal to the longitudinal direction is reduced at one end of the intake manifold main body in the longitudinal direction.
An intake manifold provided with a bypass path communicating an intermediate portion in the air flow direction in the suction passage and the one end portion in the internal space. The intake manifold according to claim 1, wherein the bypass path has a cross-sectional area smaller than the cross-sectional area of the suction passage. The suction portion has a vertical passage portion extending in a direction intersecting the longitudinal direction and opening into the internal space, and a horizontal passage portion extending in a direction along the longitudinal direction and connecting to the vertical passage portion. The intake manifold according to claim 1 or 2, wherein the bypass path is communicated with the lateral passage portion. The vertical passage portion is detachably connected to the rear portion of the vertical passage that is on the side of the intake manifold main body and the front portion of the vertical passage that is on the side of the horizontal passage portion, and the bypass path is the intake manifold main body portion. The rear part of the bypass, which is on the side of the above, and the front part of the bypass, which is on the side of the lateral passage portion, are detachably connected to each other.
In the suction portion, a suction rear portion having the vertical passage rear portion and the bypass rear portion, and a suction front portion having the vertical passage front portion, the bypass front portion, and the lateral passage portion are detachably connected to each other. The intake manifold according to any one of claims 1 to 3, wherein the intake manifold is configured by the above. One of claims 1 to 4, wherein the position of the suction portion in the longitudinal direction with respect to the intake manifold main body portion is set so that the suction passage communicates with a portion of the internal space other than the one end portion. The intake manifold described in. The suction portion has a width that intersects both the longitudinal direction of the internal space and the depth direction that is the length from the elongated opening in the internal space to the side wall located on the opposite side of the elongated opening. The intake manifold according to any one of claims 1 to 5, which has the suction passage extending in the direction of the above.
Any of claims 1 to 6, wherein the suction portion is for an in-line 4-cylinder engine formed in the in-mani main body portion at a position corresponding to the intake port of the second cylinder and the intake port of the third cylinder. The intake manifold described in item 1. The reduction in the cross-sectional area of the internal space at one end is due to the narrowing of the depth, which is the length from the elongated opening in the internal space to the side wall located on the opposite side of the elongated opening. The intake manifold according to any one of claims 1 to 7.

Images