JPH05280351A - Intake device of v-type engine - Google Patents

Abstract

PURPOSE:To improve torque trough and operational performance by providing respective first and second surge tanks on the end parts positioned downstream from first and second branch passages, and providing respective first and second volumes on the way of the first and second branch passages. CONSTITUTION:First and second cylinder heads are placed on first and second cylinder banks 6-1, 6-2 of a cylinder block. First and second head covers 10-1, 10-2 are respectively placed on these first and second cylinder heads. First and second branch passages 22-1, 22-2 are provided by branching the middle of an intake passage positioned downstream from throttle valve by means of a branch pipe 20. First and second surge tanks 24-1, 24-2 are respectively provided on the end parts positioned downstream from the first and second branch passages 22-1, 22-2. First and second volumes 28-1, 28-2 are provided on the way of the first and second branch passages. Consequently, torque trough can be improved by a resonance effect of the first and second volumes and an operational performance can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake system for a V-type engine, and particularly to mounting first and second cylinder heads on first and second cylinder banks of a cylinder block, respectively. The present invention relates to an intake device for a V-type engine in which first and second head covers are placed on a two-cylinder head to form a V-shape.

[0002]

2. Description of the Related Art As an engine of a vehicle, there are an engine having cylinders arranged in series, an engine having cylinders opposed to each other, and a V-type engine having cylinder banks arranged in a V shape.

In this V-type engine, first and second cylinder heads are mounted on first and second cylinder banks of a cylinder block, respectively, and a crankshaft is provided below the cylinder block in cooperation with the cylinder block. Some are configured with a bearing cap to support them.

In addition, in a V-type engine, in order to install an auxiliary machine such as a compressor for an air conditioner or a power steering pump, an auxiliary machine bracket is attached as a mounting bracket to the cylinder block, or the engine is mounted on the vehicle body. A mounting bracket to support it is attached.

As an intake device for a V-type engine, there is one disclosed in Japanese Patent Publication No. 62-29634. The intake manifold structure of the V-type internal combustion engine disclosed in this publication has two banks on the left and right, and the intake manifold of the V-type internal combustion engine in which the intake manifolds are arranged between these banks is provided from the intake inlet to the left and right. It is composed of branching collection pipes and branch pipes of the same number as the number of engine cylinders branching from each collection pipe, and each of the collection pipes extends in the cylinder arrangement direction of each bank, and the branch pipes face each other. Extend to the pipe side and connect to the intake port of each cylinder located on the collecting pipe side,
The length and cross-sectional area of each branch pipe of the intake manifold are sufficiently secured to improve the output of the engine, and the engine is made small and compact.

Further, there is one disclosed in Japanese Patent Laid-Open No. 2-146221. In the intake system for a V-type multi-cylinder engine disclosed in this publication, two sets of cylinder rows are arranged in a V-shape, surge tanks are arranged above each cylinder row, and an intake pipe is provided from each surge tank. An intake pipe branched from one surge tank of a V-type multi-cylinder engine branched and connected to each cylinder is provided so as to intersect or contact the surge tank on the other side, and is connected to a cylinder located below the intake pipe.
In addition, an opening with a control valve that communicates with the surge tank is provided at the portion where the intake pipe intersects or contacts the surge tank on the other side, and the control valve is configured to open at high speed and close at low speed. It is compact.

[0007]

By the way, in the conventional V-type engine intake device, as shown in FIG. 6, the V-type engine 102 is configured to have, for example, six cylinders # 1 to # 6. An intake passage 114 communicating with the cylinders # 1 to # 6 is provided.

A throttle valve 118 is arranged in the throttle body 116, and the throttle valve 1
18 is branched by a branch pipe 120 to provide first and second branch passages 122-1 and 122-2, and downstream end portions of the first and second branch passages 122-1 and 122-2. To the first and second surge tanks 124-1 and 124, respectively.
-2 is connected and provided.

The first surge tank 124-1 is connected to the first surge tank 124-1.
~ The third intake pipe 126-1 ~ 126-3 by the cylinder #
1 to # 3, the second surge tank 124-2 is connected to the fourth to sixth intake pipes 126-4 to 126-6.
Is provided by connecting to the cylinders # 4 to # 6.

The intake passage 114 is composed of a throttle body 116, a branch pipe 120, and first to sixth intake pipes 126-1 to 126-6.

However, at the location where the length of the branch pipe that connects the throttle body and the surge tank, the resonance effect due to the volume of the surge tank, and the inertial effect due to the length and diameter of the intake pipe are synchronized with the engine speed, As shown in FIG. 7, a large torque is generated, and conversely, a phenomenon where the torque is reduced, that is, a so-called trough of the torque occurs in a portion where the tuning is not performed.

As a result, the driving performance is deteriorated due to the generation of the valley of the torque, which is disadvantageous in practical use.

[0013]

Therefore, in order to eliminate the above-mentioned inconvenience, the present invention provides a first cylinder block,
The first and second cylinder heads are placed on the second cylinder bank, and the first and second head covers are placed on these first and second cylinder heads, respectively.
In an intake system for a type engine, a first branch pipe and a second branch passage are provided by branching an intermediate portion of the intake passage downstream of a throttle valve with a branch pipe. First and second surge tanks are provided, and first and second volumes are provided in the middle of the first and second branch passages, respectively.

[0014]

With the invention as described above, when the V-type engine is driven, the valley of torque is improved by the resonance effect of the first and second volumes, and the driving performance is improved.

[0015]

Embodiments of the present invention will be described in detail below with reference to the drawings.

1 to 5 show an embodiment of the present invention. 2 and 3, 2 is a V-type engine, 4
Is a cylinder block, 6-1 and 6-2 are first and second cylinder banks, 8-1 and 8-2 are first and second cylinder heads, 10-1 and 10-2 are first and second head covers. 1
2 is an oil pan.

That is, the V-type engine 2 mounts the first and second cylinder heads 8-1 and 8-2 on the first and second cylinder banks 6-1 and 6-2 of the cylinder block 4, respectively,
The first and second cylinder heads 8-1 and 8-2 have a first,
The second head covers 10-1 and 10-2 are respectively attached, a bearing cap (not shown) is attached to the lower portion of the cylinder block 4, and an oil pan 12 is attached to the lower portion of the bearing cap.

A crankshaft (not shown) is rotatably supported by the cylinder block 4 and a bearing cap (not shown) in the front-rear direction of the V-type engine 2.

Further, the V-type engine 2 is constructed to have a total of six cylinders # 1 to # 6, for example, three on one side and three on the other side, and these cylinders # 1 to # 6 are connected. An intake passage 14 is provided.

A throttle valve 18 is provided in the throttle body 16, and a downstream side of the throttle valve 18 is branched by a branch pipe 20 to provide first and second branch passages 22-1 and 22-2. First and second surge tanks 24-1 and 24-2 are connected to the downstream ends of the first and second branch passages 22-1 and 22-2, respectively.

The first surge tank 24-1 on one side is connected to the cylinder # by the first to third intake pipes 26-1 to 26-3.
1 to # 3, the second surge tank 24-2 on the other side is connected to the fourth to sixth intake pipes 26-4 to 26-6.
Is provided by connecting to the cylinders # 4 to # 6.

The intake passage 14 is connected to the throttle body 16, the branch pipe 20, and the first to sixth intake pipes 26-.
1 to 26-6.

Further, the first and second branch passages 22-1,
In the middle of 22-2, the first and second volumes 28-1 and 28-1,
28-2 is provided.

More specifically, as shown in FIG. 1, the branch pipe 20
The first branch passage 22-1 and the first volume 28-1 are connected by the first connecting pipe 32-1 having the first connection passage 30-1, and the second branch passage 22-2 and the second branch passage 22-2 are connected. The volume 28-2 is provided by being connected by a second connecting pipe 32-2 having a second connecting passage 30-2.

Then, the first and second volumes 28-1,
The volume of 28-2 is set so as to be synchronized with the engine speed which is the valley of the torque in FIG.

A first opening / closing valve 34-1 is provided in the middle of the first connection passage 30-1 and a second opening / closing valve 34-2 is provided in the middle of the second connection passage 30-2. The two open / close valves 34-1 and 34-2 are opened / closed according to the engine speed by a drive unit 36 including a vacuum or a servomotor.

First and second opening / closing valves 34-1, 34-2
As shown in FIG. 5, when the engine speed is equal to or lower than a predetermined engine speed set in advance, the open / close operation is maintained in the closed state and the engine speed exceeds the predetermined engine speed. In some cases, the opening operation is performed.

Reference numeral 38 is a communication pipe that connects the first and second surge tanks 24-1 and 24-2.

Next, the operation will be described.

When the V-type engine 2 is driven and the engine speed is equal to or lower than a predetermined engine speed, the first and second opening / closing valves 34-1 and 34-2 are kept closed. ..

Further, when the engine speed exceeds a predetermined engine speed, the drive unit 36 causes the first and second
The opening / closing valves 34-1 and 34-2 are opened to connect the first branch passage 22-1 and the first volume 28-1 with each other, and the second branch passage 22-2 and the second volume 2 are connected.
8-2 is to be contacted.

As a result, as shown in FIG.
The valley of torque can be improved by the resonance effect of the second volumes 28-1 and 28-2, and the driving performance can be improved, which is practically advantageous.

Further, by providing the first opening / closing valve 34-1 in the middle of the first connection passage 30-1 and the second opening / closing valve 34-2 in the middle of the second connection passage 30-2, the operating state High torque can be obtained in the whole area of
The usability can be improved.

The present invention is not limited to the above-mentioned embodiment, but various application modifications are possible.

For example, in the embodiment of the present invention, the first opening / closing valve is provided in the middle of the first connecting passage and the second opening / closing valve is provided in the middle of the second connecting passage. Without providing the on-off valve, the first branch passage of the branch pipe and the first volume are simply connected by the first connection pipe having the first connection passage, and the second branch passage and the second volume are connected to each other. Second with connecting passage
It may be connected by a connecting pipe, and as shown in FIG.
The resonance effect of the volume makes it possible to improve the trough of the torque and contributes to simplification of the structure.

[0036]

As described above in detail, according to the present invention, the first and second cylinder heads are mounted on the first and second cylinder banks of the cylinder block, and the first and second cylinder heads are respectively mounted. A first and a second branch passages are provided by branching a middle portion of an intake passage downstream of a throttle valve of a V-type engine on which the first and second head covers are mounted to form a V-shape. 1st and 2nd
Since the first and second surge tanks are provided at the downstream end of the branch passage, and the first and second volumes are provided in the middle of the first and second branch passages, respectively, resonance of the first and second volumes is provided. Due to the effect, the valley of torque can be improved, the driving performance can be improved, and it is practically advantageous. In addition, the first,
The first and second opening / closing valves are provided in the middle of the first and second connection passages that connect the second branch passage and the first and second volumes, and these first and second opening / closing valves are arranged according to the engine speed. With the configuration of opening and closing, a high torque can be obtained in the entire operating state, and usability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram of an intake system for a V-type engine showing an embodiment of the present invention.

FIG. 2 is a plan view of a V-type engine.

FIG. 3 is a left side view of a V-type engine.

FIG. 4 is a diagram showing a relationship between a torque depending on the presence or absence of a volume and an engine speed.

FIG. 5 is a diagram showing a relationship between torque and engine speed depending on an open / close state of an open / close valve.

FIG. 6 is a schematic view of an intake device for a V-type engine showing a conventional technique of the present invention.

FIG. 7 is a diagram showing a relationship between torque and engine speed.

[Explanation of symbols]

 2 V type engine 4 Cylinder block 6-1 1st cylinder bank 6-2 2nd cylinder bank 8-1 1st cylinder head 8-2 2nd cylinder head 10-1 1st head cover 10-2 2nd head cover 14 Intake passage 16 Throttle body 18 Throttle valve 20 Branch pipe 22-1 First branch passage 22-2 Second branch passage 24-1 First surge tank 24-2 Second surge tank 26-1 to 26-6 First to sixth intake Pipe 28-1 first volume 28-2 second volume 30-1 first connection passage 30-2 second connection passage 32-1 first connection pipe 32-2 second connection pipe 34-1 first opening / closing valve 34- 2 2nd on-off valve 36 drive part 38 communication pipe # 1- # 6 cylinder

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Saito 300, Takatsuka-cho, Hamamatsu-shi, Shizuoka Suzuki Stock Company

Claims (1)

[Claims] 1. A first and a second cylinder head are mounted on the first and second cylinder banks of a cylinder block, and a first and a second head cover are respectively mounted on these first and second cylinder heads. In a V-shaped engine intake device formed in a V-shape, first and second branch passages are provided by branching a middle portion of the intake passage downstream of a throttle valve with a branch pipe, and downstream of these first and second branch passages. An intake system for a V-type engine, characterized in that first and second surge tanks are respectively provided at side end portions thereof, and first and second volumes are respectively provided in the middle of the first and second branch passages.