JPH0455248Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a surge tank that is interposed in the intake passage of a vehicle engine and provides a stable supply of intake air.

[Prior Art] Generally, in a vehicle engine, each intake pipe is often formed to have the same length in order to obtain a uniform output between each cylinder. In addition, with the recent spread of electronically controlled fuel injection systems, vehicle engines are now equipped with surge tanks between the throttle body and intake pipe to ensure a stable supply of intake air to each cylinder. Not a few. For example, the surge tank was developed in 1983 as a prior art to the present invention.
As shown in Japanese Patent No. 13334, it is generally formed into a rectangular parallelepiped shape with an arbitrary volume and mounted parallel to the longitudinal direction of the engine body. An air inlet communicating with the inside of the throttle body is opened at one end in the longitudinal direction, and air outlets in the same number as the number of cylinders are formed in one side wall in the cylinder row direction connected to the intake pipe. is normal.

[Problems to be Solved by the Invention] However, as shown in the prior art, the air inlet is relatively often opened at one end of a rectangular parallelepiped surge tank in the longitudinal direction.
On the other hand, since the air outlet for guiding the air in the surge tank to each cylinder is opened toward each cylinder, it is substantially perpendicular to the inlet. For this reason, the air accelerated in the air hose upstream of the throttle body and inside the throttle body flows forcefully toward the side opposite to the inlet due to inertia, etc., and the air from the inlet is difficult to flow in on the outlet side near the inlet. Therefore, variations in intake air amount between cylinders tend to occur, resulting in a problem.

Furthermore, in engines equipped with electronically controlled fuel injection devices, control equipment such as a throttle opening sensor is often provided near the throttle body. Therefore, due to the need to secure a space for arranging these devices, etc., there are many cases in which the surge tank is moved parallel to the engine body and arranged on the side opposite to the inlet port. However, in such a device, the length of each intake pipe is made equal, and the intake pipe on the inlet side may be bent into an extremely bent shape near the outlet thereof toward the throttle body side. Therefore,
With such an intake pipe shape, it is further difficult for air from the inlet to flow into the outlet, which tends to cause variations in the amount of intake air between cylinders.

An object of the present invention is to provide a surge tank that can relatively easily solve these conventional problems.

[Means for Solving the Problems] In order to achieve the above object, the present invention is equipped with an air inlet and an air outlet that communicates with a plurality of intake pipes, and is formed to have equal lengths in the intake port of the engine body. In the surge tank connected via the plurality of intake pipes, the rear wall is formed into a gently curved shape so as to be convex inward, and the inlet is located at a higher position than the outlet in the longitudinal end face. and is characterized in that it is opened obliquely to the rear wall, and the inlet is substantially facing the direction of the outlet opening near the inlet.

[Function] According to such a configuration, the air inlet almost faces the outlet near the inlet, and the rear wall is gently curved with an inward convex surface, so that air from the inlet The air that flows into the surge tank efficiently flows into the outlet near the inlet, and is guided by the rear wall and similarly flows into the outlet located further away from the inlet. . As a result, the air in the surge tank is uniformly discharged from each outlet and guided from each intake port to the combustion chamber via a plurality of intake pipes formed to have equal lengths.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

FIG. 1 is a plan view schematically showing the front part of a passenger car type vehicle body that employs a front engine/front drive system.

The vehicle 1 shown in the drawing has an engine body 3 placed horizontally in an engine room 2. An exhaust pipe (not shown) is attached to the front end of the engine body 3, and an intake system and an air intake system are installed in the passenger compartment 4 side. A fuel supply device (not shown) such as an injector is provided to mix fuel into the intake system. The air cleaner of the intake system and the throttle body 5 downstream thereof are connected via an air hose 6, and a surge tank 7 is connected downstream of the throttle body 5 to enable a stable supply of air to each cylinder. Surge tank 7 is
A brake booster 10 is fixed to a dash panel 9 on the air inlet 8 side opened in the end wall 7a.
It is located on the side, and is also slightly displaced in parallel with respect to the engine main body 3 in the direction of the cylinder row on the side opposite to the inlet.

Then, connect the surge tank 7 to the engine body 3.
It is connected to the intake port 11 of the cylinder via a plurality of intake pipes 12 for each cylinder, which are formed to have equal lengths. The intake pipe 12 includes a front part 13 formed integrally with the surge tank 7 and a rear part 14 detachably interposed between the front part 13 and the engine body 3. The front section 13 is composed of branch sections 15 to 18 for each cylinder that extend downward in a curved manner from the rear wall 7b of the surge tank on the side of the dash panel 9, and branch sections 15 and 16 that extend from the side of the inlet 8.
In consideration of the positional relationship of the surge tank 7, equal length of each intake pipe 12, etc., it has a relatively steep curved shape toward the throttle body 5 side. Air passages 15a to 18a are formed inside each branch portion 15 to 18 to guide air in the surge tank 7 to each cylinder. And these air passages 15a to 18
One end of a is opened at the lower part of the inner surface of the rear wall 7b of the surge tank to serve as air outlet ports 15b to 18b, and the other end is opened at the end surface 19a of a series of flanges 19 formed at the lower end of the front section 13, and the other end is opened at the end surface 19a of a series of flanges 19 formed at the lower end of the front section 13. Connection ports 15c to 15c communicate with each of the branch parts 20 to 23 of the portion 14.
It is 18c.

The rear stage part 14 interposed between the front stage part 13 and the engine main body 3 has branch parts 20 to 20 which are curved in a substantially horizontal direction in the mounting position and make each intake pipe 12 the same length.
23, and inside it there is a front section 1.
Air passages 20a to 23a are formed which communicate with the three air passages 15a to 18a, respectively. One end of each of these air passages 20a to 23a is connected to the front section 1.
The connection ports 15c to 18c are opened in the end surface 24a of the flange 24 connected to the flange 19 of No. 3.
The other end is opened in an end surface 25a of a flange 25 connected to the engine main body 3 to form connection ports 20c to 23c that communicate with the intake port 11. And the front part 1
Each of the air passages 15a to 18a of No. 3 is communicated with each of the air passages 20a to 23a of the corresponding rear section 14 at the flanges 19 and 24, and the inside of the surge tank 7 and the intake port 11 are communicated with each other at the same length. .

Note that the openings 26 to 29 formed in the vicinity of each of the connection ports 20c to 23c of the rear part 14 are for mounting an injector for injecting fuel into the intake port 11.

On the other hand, the surge tank 7 gradually moves away from the engine body 3 from the central portion to the end wall 7a side, while the surge tank 7 gradually moves away from the engine body 3 from the center portion to the end wall 7a side.
It is formed into a gentle curve that points to the side. Then, the outlet ports 15b, 16b of the branch portions 15, 16 located on the outlet side where air from the inlet 8 is difficult to flow into the central portion of the end wall surface 7c, that is, on the inlet 8 side.
The introduction port 8 is opened toward the side. To be more specific, the inlet 8 opens obliquely toward the inner surface 7d of the rear wall 7b where the outlets 15b, 16b, etc. are opened, and
The height position is different from that of the other parts, and is formed at a higher position.

According to such a configuration, the air flowing into the surge tank 7 from the inlet 8 at an accelerated rate flows through the inlet 8
It is led from the outlet ports 15b, 16b located on the sides and the inner surface 7d side above them to the other outlet ports 17b, 18b. The air led into the surge tank in this way is delivered to the front section 13 extending below the rear wall 7b from each outlet 15b to 18b, and to the rear section extending further from below the front section 13 toward the engine body 3. Each of the air passages 15a to 18a, 20a to 12 in the intake pipe 12 is formed to have the same length as the part 14.
20a and is led to the intake port 11 of the engine body 3.

Therefore, if the configuration is like this,
In order to accommodate the throttle body 5, air hose 6, etc. attached to the inlet 8 side, the surge tank 7 is placed offset from the engine body 3, and the intake pipe 12 has a relatively sharp bend. Even in the device having the branch portions 15 and 16, since the inlet port 8 is opened toward the outlet ports 15b and 16b of the branch portions 15 and 16, the air flowing into the surge tank 7 at an accelerated rate is can be guided toward these introduction ports 15b and 16b. Therefore, a problem in which the amount of air flowing into the inlet ports 15b and 16b is smaller than that of the other inlet ports 17b and 18b is avoided, and the air in the surge tank 7 is supplied from each of the outlet ports 15b to 18b in excess and deficiency. can flow out.

Each of the outlet ports 15b to 18b and the intake port 11 of the engine body 3 are connected to each other by air passages 15a to 18a, 20a to 23a in the intake pipe 12, which are made equal in length by the front part 13 and the rear part 14. Coupled with the communication, it becomes possible to introduce the air in the surge tank 7 to the intake port 11 under substantially equal conditions, and it is possible to obtain stable output without causing variations in each cylinder.

Also, the degree of inclination of the inlet 8 with respect to the opening surface of the outlet ports 15b and 16b is determined for each outlet port 15b to 18b.
It is also possible to consider the amount of air flowing out from and change or adjust it as appropriate.

In the above embodiment, separate outlet ports are formed on the rear wall of the surge tank leading to a plurality of intake pipes, but the present invention is not necessarily limited to this. It can also be effectively applied to a device with an open outlet.

Alternatively, the intake pipe is not limited to being composed of a front part integrally formed with the surge tank and a rear part located on the engine main body side, but may be integrally formed with equal length.

[Effects of the invention] As detailed above, in the present invention, the air inlet is opened so as to face the outlet near the inlet, and the rear wall is shaped to be a convex inner surface and gently curved. By doing so, it is possible to provide a surge tank that can substantially equalize the amount of air flowing out from each outlet, and by using it in combination with multiple intake pipes formed to the same length, it is possible to Almost the same stable output can be obtained.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention,
Fig. 1 is a plan view schematically showing the front of the vehicle body, Fig. 2 is a plan view of the surge tank and intake pipe, Fig. 3 is a front view of the surge tank and intake pipe, and Fig. 4 is a surge tank and intake pipe. It is a side view of a partial cross section. 1... Vehicle body, 3... Engine body, 5... Throttle body, 7... Surge tank, 7a... End wall, 7b... Rear wall, 8... Air inlet, 10...
Brake booster, 11... Intake port, 12...
...Intake pipe, 13... Front section, 14... Rear section, 1
5a to 18a... air passage, 15b to 18b...
Outlet ports, 20a to 23a...air passages.

Claims (1)

[Scope of utility model registration request] In a surge tank that is equipped with an air inlet and an air outlet that communicates with a plurality of intake pipes, and is connected to an intake port of an engine body via the plurality of intake pipes formed to have equal lengths, the rear wall is connected to the inner side. The inlet is formed into a warm curved shape so as to have a convex surface, and the inlet is
It is characterized by having an opening in the longitudinal end face at a higher position than the outlet and in a diagonal direction with respect to the rear wall, and the inlet opening substantially faces the direction of the outlet opening near the inlet. Surge tank.