JP2016094841A - Intake manifold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an intake manifold for increasing the amount of intake air flowing in a branch pipe farthest from an intake inlet of a surge tank while uniforming the amount of the intake air flowing in the plurality of branch pipes among the branch pipes.SOLUTION: An intake manifold 1 includes a surge tank 11 having a first end 11a and a second end 11b at both ends in the longitudinal direction, one intake inlet (16) arranged shifted to the side of the first end 11a of the surge tank 11, and a plurality of branch pipes 12-15 arranged in parallel along the longitudinal direction of the surge tank 11. The surge tank 11 is formed with the inlets of the branch pipes 12-15. At the front end of each of the branch pipes 12-15, an intake outlet is formed out of which the intake air flows. At the second end 11b of the surge tank 11, positioned adjacent to the most-distant branch pipe 15 farthest from the intake inlet (16), a sub chamber 17 is provided which is communicated with the surge tank 11 for promoting the flow of the intake air into the most-distant branch pipe 15.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an intake manifold provided in a multi-cylinder engine and configured to distribute intake air flowing through an intake passage to each cylinder.

  Conventionally, this type of intake manifold is well known, and includes a surge tank into which intake air flows from one intake inlet, and a branch pipe branched into a plurality of branches to distribute the intake air from the surge tank to each cylinder of the engine. . An intake outlet through which intake air flows out to each cylinder is provided at the tip of each branch pipe. One of the functions generally required for an intake manifold is to uniformly distribute intake air to each cylinder. Here, as the flow path length and flow path shape from the intake inlet of the surge tank to the intake outlet of each branch pipe are the same between the branch pipes, the intake air distributed to each cylinder through the intake manifold is more uniform. It will be something. Therefore, for example, in a four-cylinder engine, it is ideal to arrange the intake inlet of the surge tank in the center in the longitudinal direction of the surge tank and arrange two branch pipes on the left and right with the intake inlet at the center. It becomes composition.

  However, depending on various conditions required for the engine, it is difficult to dispose the intake inlet at the center of the surge tank, and it may be necessary to dispose the intake inlet at one end in the longitudinal direction of the surge tank. Patent Document 1 listed below describes this type of offset type intake manifold. In such an offset type intake manifold, the flow path length from the intake inlet to the intake outlet becomes longer as the branch pipe is farther from the intake inlet than the branch pipe close to the intake inlet of the surge tank (induction chamber). For this reason, as the branch pipe is farther from the intake inlet, the intake resistance associated with the branch pipe increases, and the amount of intake air flowing through the branch pipe decreases. As a result, it becomes difficult to uniformly distribute the intake air to the cylinders of the engine, and there is a possibility that the combustion of fuel in each cylinder becomes non-uniform.

  Here, in the intake manifold of Patent Document 1, in order to ensure the intake amount required by the engine without increasing the intake resistance, the surge tank is adjacent to the branch pipe farthest from the intake inlet, An auxiliary chamber is provided in communication with the surge tank. The volume of the surge tank is increased by the auxiliary chamber to increase the intake amount distributed from the surge tank to each cylinder.

JP-A-6-42419

  However, in the intake manifold described in Patent Document 1, although the volume of the surge tank can be expanded by the auxiliary chamber, the intake air flowing through the branch pipe farthest from the intake inlet cannot be increased, and a plurality of branches It was not possible to make the intake air flowing between the tubes uniform.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to increase the amount of intake air flowing through the branch pipes farthest from the intake inlet of the surge tank, and to distribute them among a plurality of branch pipes. An object of the present invention is to provide an intake manifold that makes it possible to equalize the amount of intake air flowing.

  In order to achieve the above-mentioned object, the invention according to claim 1 is arranged in a surge tank having a first end and a second end at both ends in the longitudinal direction, respectively, and is shifted toward the first end side of the surge tank, One intake inlet for introducing intake air into the surge tank, multiple branch pipes arranged in parallel along the longitudinal direction of the surge tank, for distributing intake air from the surge tank to multiple cylinders of the engine, and surge In the intake manifold, the tank is formed with an inlet of each branch pipe, and an intake outlet for discharging the intake air is formed at the tip of each branch pipe. The purpose is to provide a sub-chamber that communicates with the surge tank in order to promote the flow of intake air to the farthest branch pipe at a position adjacent to the farthest branch pipe farthest from the intake inlet.

  According to the configuration of the above invention, the intake manifold assembled to the engine allows intake air to flow into the surge tank from the intake inlet when the engine is operated. Then, when the cylinders corresponding to the branch pipes are in the intake stroke, intake air flows from the surge tank through the inlet of the branch pipe to each branch pipe, and the intake air flows out from the intake outlet to the corresponding cylinder for distribution. . Here, a part of the intake air flowing into the surge tank also flows into the sub chamber. When the intake air flows into the farthest branch pipe adjacent to the sub chamber, the intake air that has once flowed into the sub chamber reverses the direction and flows to the farthest branch pipe.

  In order to achieve the above object, according to a second aspect of the present invention, in the first aspect of the present invention, the flow of the intake air from the intake inlet and the intake air from the sub chamber are immediately before the inlet of the farthest branch pipe. The purpose is to arrange the farthest branch pipe and the sub chamber side by side so that the flow merges.

  According to the configuration of the above invention, in addition to the operation of the invention according to claim 1, the flow of intake air from the intake inlet and the flow of intake air from the sub chamber are merged immediately before the entrance of the farthest branch pipe. , The bias of the intake air distribution in the farthest branch pipe is reduced.

  In order to achieve the above object, the invention according to claim 3 is the invention according to claim 1 or 2, wherein the center of the intake inlet and the center of the sub chamber are arranged on substantially the same plane, The purpose is to form a subchamber opening over the entire second end.

  According to the configuration of the above invention, in addition to the operation of the invention according to claim 1 or 2, the center of the intake inlet and the center of the sub chamber are arranged on substantially the same plane, and the entire area of the second end of the surge tank is Since the sub chamber is opened, the flow of intake air from the intake port to the sub chamber is smooth.

  In order to achieve the above object, the invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the sub chamber is formed by extending in a direction in which the farthest branch pipe extends. Intended to be

  According to the configuration of the invention, in addition to the action of the invention according to any one of claims 1 to 3, since the sub chamber is formed by extending in the direction in which the farthest branch pipe extends, the length of the surge tank The volume of the sub chamber is increased without increasing the size of the sub chamber in the direction.

  In order to achieve the above object, according to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the cross-sectional area perpendicular to the longitudinal direction of the surge tank is from the side where the intake inlet is located. The purpose is that the surge tank is formed so as to gradually decrease toward the side where the sub chamber is located.

  According to the configuration of the invention, in addition to the operation of the invention according to any one of claims 1 to 4, the cross-sectional area perpendicular to the longitudinal direction of the surge tank is such that the side where the sub chamber is located from the side where the intake inlet is located. Therefore, the flow rate of the intake air flowing from the intake inlet toward the sub chamber increases.

  In order to achieve the above object, the invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein a pressure sensor for detecting the pressure in the surge tank is provided in the sub chamber. The purpose is that.

  According to the configuration of the above invention, in addition to the operation of the invention according to any one of claims 1 to 5, in the sub chamber, the influence of the intake pulsation is small compared to the surge tank, and the fluctuation of the pressure detected by the pressure sensor is small. Less.

  According to the first aspect of the present invention, the amount of intake air flowing through the farthest branch pipe farthest from the intake inlet of the surge tank can be increased, and the amount of intake air flowing through the plurality of branch pipes is uniform. Can be achieved.

  According to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the amount of intake air flowing through the farthest branch pipe can be further increased.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, it is possible to efficiently flow the intake air from the intake inlet to the sub chamber, and from the sub chamber to the farthest branch pipe. A large amount of intake air can be flowed, and in this sense, the sub chamber can be miniaturized.

  According to the invention described in claim 4, in addition to the effect of the invention described in any one of claims 1 to 3, the branch pipe farthest from the sub chamber without increasing the size of the sub chamber in the longitudinal direction of the surge tank. It is possible to further increase the amount of intake air flowing into the vehicle.

  According to the invention of claim 5, in addition to the effect of the invention of any of claims 1 to 4, it is possible to increase the amount of intake air flowing from the intake inlet to the farthest branch pipe and sub chamber, The amount of intake air flowing from the sub chamber to the farthest branch pipe can be further increased.

  According to the invention described in claim 6, in addition to the effect of the invention described in any one of claims 1 to 5, it is possible to improve the detection accuracy of the pressure of the surge tank by the pressure sensor.

1 is a side view showing an intake manifold assembly including an intake manifold according to one embodiment. The top view of FIG. 1 which concerns on one Embodiment and shows an intake manifold assembly. The bottom view of FIG. 1 which concerns on one Embodiment and shows an intake manifold assembly. FIG. 3 is a cross-sectional view taken along line AA of FIG. 2 showing an intake manifold assembly according to one embodiment. The side view which concerns on one Embodiment and decomposes | disassembles and shows an intake manifold. The top view of FIG. 5 which concerns on one Embodiment and shows a lower case. The bottom view of FIG. 5 which concerns on one Embodiment and shows an upper case. The top view outline figure showing an intake manifold concerning one embodiment. The top view outline figure which concerns on a prior art example and shows an intake manifold. The graph which shows the difference of the flow volume of the intake air which flows into each cylinder in 4 steps | paragraphs of intake strokes of a 4-cylinder engine as compared with a prior art example.

  Hereinafter, an embodiment of an intake manifold according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a side view showing an intake manifold assembly 2 including an intake manifold 1 of this embodiment. In FIG. 1, the left side is defined as the “front side” of the intake manifold assembly 2, and the right side is defined as the “rear side” of the assembly 2. FIG. 2 is a plan view of the intake manifold assembly 2 shown in FIG. FIG. 3 is a bottom view of the intake manifold assembly 2 shown in FIG. FIG. 4 shows the intake manifold assembly 2 by a cross-sectional view taken along line AA of FIG. As shown in FIGS. 1 to 3, the intake manifold assembly 2 is configured by integrally integrating a throttle device 3, an EGR valve 4, and a pressure sensor 5 with a resin intake manifold 1. The intake manifold 1 includes a surge tank 11 and a plurality (four in this embodiment) of branch pipes 12, 13, 14, and 15. The throttle device 3 is for adjusting the amount of intake air flowing from the intake passage to the intake manifold 1 and includes a throttle sensor 6 that incorporates a throttle valve and detects the opening of the throttle valve. The throttle device 3 is connected to operating means (both not shown) via wires, and is opened and closed by operating the operating means by the driver. The EGR valve 4 is for adjusting the amount of EGR gas flowing to the intake manifold 1 and incorporates a valve body driven by a motor. The pressure sensor 5 is for detecting the pressure in the surge tank 11.

  FIG. 5 is an exploded side view of the intake manifold 1. As shown in FIG. 5, the intake manifold 1 is formed by joining an upper case 21 made of resin and a lower case 22 to each other. FIG. 6 shows the lower case 22 as a plan view of FIG. FIG. 7 shows the upper case 21 from the bottom view of FIG. As shown in FIGS. 6 and 7, joint allowances 22 a and 21 a for joining the cases 22 and 21 to each other are formed on the outer periphery of the upper surface of the lower case 22 and the outer periphery of the bottom surface of the upper case 21.

  As shown in FIGS. 1-7, the surge tank 11 has the 1st end 11a and the 2nd end 11b in each of the both ends of the longitudinal direction (up-down direction of FIG. 2). In the surge tank 11, one intake inlet 11c (see FIG. 6) for allowing intake air to flow into the tank 11 is disposed so as to be offset toward the first end 11a. The intake inlet 11 c is disposed on the front side of the surge tank 11. A short cylindrical connecting pipe 16 protruding forward from the surge tank 11 is formed at the intake inlet 11c. The throttle device 3 is attached to the connecting pipe 16. The four branch pipes 12 to 15 are for distributing intake air from the surge tank 11 to the four cylinders of the engine, and are arranged in parallel (side by side) along the longitudinal direction on the rear side of the surge tank 11. . As shown in FIG. 4, inlets 12 a, 13 a, 14 a, and 15 a of the branch pipes 12 to 15 are formed on the rear side of the surge tank 11. As shown in FIG. 3 and FIG. 6, intake outlets 12 b, 13 b, 14 b, and 15 b for allowing the intake air to flow out are formed at the tips of the branch pipes 12 to 15.

  As shown in FIGS. 1 to 7, among the four branch pipes 12 to 15 arranged in parallel on the rear side of the surge tank 11, the branch pipe 15 closest to the second end 11 b of the surge tank 11 is the surge tank. 11 is the farthest branch pipe 15 farthest from the intake inlet 11c. A sub-chamber 17 communicating with the surge tank 11 is provided at a position adjacent to the farthest branch pipe 15 in order to promote the flow of intake air to the branch pipe 15.

  In this embodiment, as shown in FIG. 4, as shown in FIG. 4, the flow of intake air from the intake port 11c and the flow of intake air from the sub chamber 17 are merged immediately before the inlet 15a of the farthest branch pipe 15. The far branch pipe 15 and the sub chamber 17 are arranged side by side (in parallel).

  Further, in this embodiment, as shown in FIG. 6, the center C1 of the intake port 11c and the center C2 of the sub chamber 17 are arranged on substantially the same plane, and the sub-portion is spread over the entire area of the second end 11b of the surge tank 11. An opening 17a of the chamber 17 is formed. As a result, the intake air flowing into the surge tank 11 from the intake inlet 11c flows smoothly and substantially linearly toward the sub chamber 17 without being refracted in the vertical direction in FIG. It is like that.

  Further, in this embodiment, as shown in FIGS. 2, 3, 6, and 7, the sub chamber 17 extends in the direction in which the furthest branch pipe 15 extends (the direction of arrow Y in FIG. 6: rearward). Formed. Further, as shown in FIG. 7, an attachment port 21 b for attaching the pressure sensor 5 is formed in a portion constituting the sub chamber 17 of the upper case 21. Thus, the pressure sensor 5 is provided in the sub chamber 17 as shown in FIGS.

  In this embodiment, as shown in FIG. 2, the surge tank 11 has a substantially triangular shape whose width is gradually narrowed from the first end 11 a toward the second end 11 b. That is, the cross-sectional area of the surge tank 11 orthogonal to the longitudinal direction of the surge tank 11 (the direction of the arrow X in FIG. 2) gradually decreases from the side where the intake inlet 11c is located toward the side where the sub chamber 17 is located. In addition, the surge tank 11 is formed in a substantially triangular shape in plan view.

  The intake manifold 1 of this embodiment described above has the following operational effects. That is, in the intake manifold 1 assembled to the engine, intake air flows into the surge tank 11 from the intake inlet 11c when the engine is operated. And when the cylinder of the engine corresponding to these branch pipes 12-15 becomes an intake stroke, intake air flows into each branch pipe 12-15 from the inlet 12a-15a of each branch pipe 12-15 from the surge tank 11. Then, the intake air flows out from each intake outlet 12b to 15b to the corresponding cylinder and is distributed. Here, a part of the intake air flowing into the surge tank 11 also flows into the sub chamber 17. When the intake air flows into the farthest branch pipe 15 adjacent to the sub chamber 17, the intake air that has once flowed into the sub chamber 17 reverses the direction and flows to the farthest branch pipe 15. For this reason, the intake air amount flowing through the farthest branch pipe 15 farthest from the intake inlet 11c of the surge tank 11 can be increased, and the intake air amount flowing through the plurality of branch pipes 12 to 15 can be made uniform. You can plan.

  FIG. 8 shows an intake manifold 1 of this embodiment in a plan view outline view. FIG. 9 is a plan view of an intake manifold 30 of a conventional example. When the cylinder corresponding to the farthest branch pipe 15 enters the intake stroke with the intake manifold 1 attached to the engine, the intake air flowing into the surge tank 11 from the intake inlet 11c is indicated by a thick arrow in FIG. To the inlet 15a of the farthest branch pipe 15. Further, a part of the intake air flowing into the surge tank 11 from the intake inlet 11c once flows into the sub chamber 17 and reverses its direction, as shown by the broken line arrow in FIG. 8, toward the inlet of the farthest branch pipe 15. Flowing. In contrast, in the intake manifold 30 of the conventional example, the intake air flowing into the surge tank 31 from the intake inlet 31a in the intake stroke only flows toward the farthest branch pipe 35 as shown by a thick arrow in FIG. is there.

  FIG. 10 is a graph showing the difference in the flow rate of the intake air flowing through the cylinders # 1, # 2, # 3, and # 4 in the intake stroke of the 4-cylinder engine in comparison with the conventional example. In FIG. 10, the hatched bar graph indicates the case where the conventional intake manifold 30 without the sub chamber is used, and the open bar graph indicates the case where the intake manifold 1 of the present embodiment having the sub chamber 17 is used. Indicates. 10, the first cylinder # 1 sucks intake air from the branch pipes 12 and 32 closest to the intake inlets 11c and 31a of FIGS. 8 and 9, and the second cylinder # 2 The third cylinder # 3 sucks intake air from the branch pipes 14 and 34 of FIGS. 8 and 9, and the fourth cylinder # 4 receives the intake air from the branch pipes 13 and 33 of FIG. Inhale air from the farthest branch pipes 15 and 35. As can be seen from FIG. 10, in the conventional example, the flow rate is the smallest in the fourth cylinder # 4, and the flow rate increases in the order of the third cylinder # 3, the second cylinder # 2, and the first cylinder # 1. The flow rate of the fourth cylinder # 4 is as small as about half that of the first cylinder # 1. In contrast, in the present embodiment, the flow rates of the first and second cylinders # 1 and # 2 are the same as those of the conventional example, but the flow rate of the fourth cylinder # 4 is increased and the flow rate of the second cylinder # 2 is increased. It is understood that it is almost the same. This is considered to be an effect of providing the sub chamber 17 adjacent to the farthest branch pipe 15. Further, the flow rate of the third cylinder # 3 is slightly smaller than the flow rate of the fourth cylinder # 4, but it can be seen that the flow rate has increased compared to the conventional example. It can be seen that the effect of the sub chamber 17 has spread to the branch pipe 14 adjacent to the farthest branch pipe 15.

  In this embodiment, as shown by the bold arrows and the broken line arrows in FIG. 8, the flow of intake air from the intake inlet 11 c and the flow of intake air from the sub chamber 17 immediately before the inlet 15 a of the farthest branch pipe 15 are Since they merge, the bias of the intake air distribution in the farthest branch pipe 15 is reduced. In this sense, the amount of intake air flowing through the farthest branch pipe 15 can be further increased.

  In this embodiment, the center of the intake inlet 11c and the center of the sub chamber 17 are arranged on substantially the same plane, and the entire area of the second end 11b of the surge tank 11 becomes the opening 17a of the sub chamber 17, so that the intake inlet 11c To the sub chamber 17 becomes smooth. For this reason, it is possible to efficiently flow the intake air from the intake inlet 11c to the sub chamber 17, and it is possible to flow more intake air from the sub chamber 17 to the farthest branch pipe 15. In this sense, the sub chamber 17 is downsized. can do.

  In this embodiment, since the sub chamber 17 is formed by extending in the direction in which the farthest branch pipe 15 extends, the volume of the sub chamber can be increased without enlarging the size of the sub chamber 17 in the longitudinal direction of the surge tank 11. Enlarged. For this reason, the amount of intake air flowing from the sub chamber 17 to the farthest branch pipe 15 can be further increased without increasing the size of the sub chamber 17 in the longitudinal direction of the surge tank 11.

  In this embodiment, the cross-sectional area perpendicular to the longitudinal direction of the surge tank 11 gradually decreases from the side where the intake inlet 11c is located toward the side where the sub chamber 17 is located. Increases the flow rate of the flowing intake air. In this sense, the amount of intake air flowing from the intake inlet 11c to the farthest branch pipe 15 and the sub chamber 17 can be increased, and the amount of intake air flowing from the sub chamber 17 to the farthest branch pipe 1 can be further increased. .

  In this embodiment, the sub chamber 17 is less affected by the intake pulsation than the surge tank 11 and the pressure fluctuation detected by the pressure sensor 5 is reduced. For this reason, the detection accuracy of the pressure of the surge tank 11 by the pressure sensor 5 can be improved.

  In addition, this invention is not limited to the said embodiment, A part of structure can be changed suitably and implemented in the range which does not deviate from the meaning of invention.

  For example, in the above-described embodiment, the present invention is embodied in the intake manifold 1 having four branch pipes 12 to 15 according to a four-cylinder engine, but the number of branch pipes is other than four according to the number of cylinders of the engine. The number can be changed.

  Moreover, in the said embodiment, limited structures other than the structure which provides the subchamber 17 in the surge tank 11 can also be abbreviate | omitted suitably.

  The present invention can be used for an intake system of a vehicle engine or a marine engine.

1 intake manifold 5 pressure sensor 11 surge tank 11a first end 11b second end 11c intake inlet 12 branch pipe 12a inlet 12b intake outlet 13 branch pipe 13a inlet 13b intake outlet 14 branch pipe 14a inlet 14b intake outlet 15 farthest branch pipe 15a Inlet 15b Intake outlet 17 Sub chamber 21b Mounting hole

Claims (6)

A surge tank having a first end and a second end at both ends in the longitudinal direction;
One intake inlet arranged to be shifted toward the first end of the surge tank, and for allowing intake air to flow into the surge tank;
A plurality of branch pipes arranged in parallel along the longitudinal direction of the surge tank, for distributing intake air from the surge tank to a plurality of cylinders of the engine;
In the intake manifold, the surge tank is provided with an inlet of each branch pipe, and an intake outlet for discharging the intake air is formed at a tip of each branch pipe.
In order to promote the flow of intake air to the farthest branch pipe at the second end of the surge tank and adjacent to the farthest branch pipe farthest from the intake inlet, the surge tank An intake manifold characterized in that a sub-chamber communicating with the intake is provided.   The farthest branch pipe and the sub chamber are arranged side by side so that the flow of intake air from the intake inlet and the flow of intake air from the sub chamber merge just before the entrance of the farthest branch pipe. The intake manifold of claim 1.   The center of the intake inlet and the center of the sub chamber are arranged on substantially the same plane, and the opening of the sub chamber is formed in the entire area of the second end of the surge tank. Intake manifold as described in   The intake manifold according to any one of claims 1 to 3, wherein the sub chamber is formed by extending in a direction in which the farthest branch pipe extends.   The surge tank is formed so that a cross-sectional area perpendicular to the longitudinal direction of the surge tank gradually decreases from a side where the intake inlet is located toward a side where the sub chamber is located. The intake manifold according to any one of 1 to 4.   The intake manifold according to any one of claims 1 to 5, wherein a pressure sensor for detecting a pressure in the surge tank is provided in the sub chamber.

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