JPH0658142A - Exhaust gas manifold structure for dynamic pressure supercharged engine - Google Patents

Abstract

PURPOSE:To reduce the capacity of a manifold and reduce the size by a method wherein an exhaust gas manifold comprises an inner confluence manifold, an outer confluence manifold, a two-exhaust port manifold, and a one-exhaust port manifold, and exhaust gas interference is prevented from occurring when an ignition order is varied. CONSTITUTION:Exhaust gas of cylinders 1-8 is collected to inner and outer confluence manifolds A and C and fed to an exhaust gas turbine 26 to rotate a blower 27 of a supercharger. When an ignition order is varied in the case rated rotation of an internal combustion engine is varied, variation is practicable following the variation such that an exhaust gas manifold group wherein exhaust gas interference is lowermost is constituted. For example, in the case an ignition order is set to 1 2 4 6 8 7 5 3, a group of exhaust gas manifolds is constituted such that 1-4-5-8 are collected in one set to the outer confluence manifold C and 2-3-6-7 are collected in one set to the inner confluence manifold A. This constitution causes reduction of exhaust gas interference to a minimum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention makes it possible to continuously operate an internal combustion engine at a rotational speed with a large amount of torsional vibration when the same ignition sequence is used when the most frequently used rotational speed of the internal combustion engine is changed. The sexuality occurs. In this way, when the desired engine speed changes, it is necessary to change the ignition order of the internal combustion engine, and when the ignition order is changed in this way, when using the dynamic pressure supercharged engine, the capacity of the manifold is reduced. Since the size is not increased, it becomes necessary to change the group of exhaust manifolds of the group configuration in order to avoid exhaust interference. Even when the group structure of the exhaust manifolds is changed, the structure of the exhaust manifolds can be easily changed.

[0002]

2. Description of the Related Art Conventionally, a technique of forming exhaust manifolds into groups has been publicly known. For example, Japanese Patent Publication 2
This is the same as the technique described in JP-A-6-6553 and JP-A-57-134315. Also, as a technique for making the exhaust manifold connectable and separable, a technique described in Japanese Utility Model Laid-Open No. 59-22926 is known.

Further, conventionally, when an eight-cylinder internal combustion engine is equipped with a single supercharger, the following exhaust manifold is used. First, a dynamic pressure supercharging system for a pulse converter with four groups. In this case, the exhaust manifold has many pipes, the structure is complicated, and many supports are required, so that there is a problem that the pipe volume is large as compared with the present invention. Second, a static pressure supercharging system with a single group. In this case, as compared with the first case, a larger pipe volume is required, and in a gas engine etc. in which the air-fuel mixture is quantitatively controlled by a throttle in front of the air supply manifold, the loss for the throttle is covered. In order to do that, an extremely efficient supercharger was needed. In general, a highly efficient supercharger was used to secure the performance under partial load.

[0004]

The problems to be solved by the present invention are as follows. First, since the rotational speed at which the torsional vibration is generated changes depending on the ignition order, in the generator specifications, when the required rotational speed of the internal combustion engine is different between the 50 Hz region and the 60 Hz region, if the rotational speed is changed, In order to avoid the rotational speed at which torsional vibration occurs, it is necessary to change the ignition order. In this way, when the ignition order is changed, the group configuration of the exhaust manifolds can be easily changed to avoid exhaust interference. Also in the case of internal combustion engines used other than generators, the number of revolutions may be changed according to the desired rated output, and the ignition sequence may be changed accordingly. It is easy to change the group structure of the manifolds. Second, it does not require a highly efficient turbocharger such as the static pressure supercharging system. Thirdly, the pipe volume should be more compact. Fourth, the structure is simple and maintenance is easy.

[0005]

The problems to be solved by the present invention are as described above. Next, the means for solving the problems will be described. That is, in an internal combustion engine of a dynamic pressure supercharging system equipped with a single supercharger with in-line 8 cylinders, an exhaust manifold is composed of an inner merging manifold, an outer merging manifold, two exhaust manifolds, and one exhaust manifold. However, when changing the ignition sequence of the internal combustion engine, it is possible to change to a group configuration that avoids exhaust interference.

[0006]

[Operation] Next, the operation will be described. First, in FIG. 10, 5
Torsional vibration will be described in an internal combustion engine for a generator of 0 Hz / 1500 revolutions. In the case of FIG. 10, the ignition sequence of the 8-cylinder internal combustion engine is such that the ignition sequence is 1 → 2 → 4 → 6 → 8 → 7 → 5 → 3. In this case, as shown in FIG.
As described above, the torsional vibration is reduced in the vicinity of 1500 rotations. However, the ignition sequence remains the same, 60H
When the rotational speed of the internal combustion engine is increased to 1800 rpm for z power generation, a large torsional vibration occurs in the vicinity of 1800 rpm in FIG. 10, so the internal combustion engine in the ignition order cannot be used. It becomes.

Therefore, in order to use for 60 Hz / 1800 revolutions, it is necessary to set the ignition sequence in the vicinity of 1800 revolutions without torsional vibration as shown in FIG.
In this case, as an example, 1 → 3 → 7 → 5 → 2 → 4 → 8
→ It is necessary to set the ignition sequence as 6. In order to form a group structure so that exhaust interference does not occur in this ignition sequence, FIG.
As described above, the group configuration such as 1-2-7-8 and 4-5-6-7 has the smallest exhaust interference.

As described above, the predetermined number of rotations, for example, 150
When constantly rotating at different rotation speeds of 0 rotation and 1800 rotations, the torsional vibration may be large or small at the rotation speed. In order to change the torsional vibration, it is necessary to change the ignition order. There is. If the ignition order is changed, the group structure that does not cause exhaust interference becomes different, and it is necessary to change the exhaust manifold of the group structure as shown in FIGS. 1 and 2. The present invention provides an exhaust manifold having a group structure that can be easily mounted and changed even when the group structure is changed.

[0009]

EXAMPLES Next, examples will be described. Fig. 1 is 1-4-5
8 and 2-3-6-7 are a front view of an internal combustion engine showing an exhaust manifold in the case of a group configuration, and FIG. 2 is 1-2-7-8
And a front view of an internal combustion engine showing an exhaust manifold when 3-4-5-6 is configured as a group, FIG. 3 is a side view of the internal combustion engine showing a supercharger and an exhaust manifold portion, and FIG. 4 is an exhaust manifold. FIG. 5 is a front view of the outer merging manifold C, FIG. 6 is a front view of the inner merging manifold A, FIG. 7 is a front view of the two exhaust port manifold B, and FIG. FIG. 9 is a front view of the exhaust pipe manifold D, FIG. 9 is a front view of the connecting pipe 12, FIG.
It is drawing which shows torsional vibration in case of z * 1800 rotation.

This will be described with reference to FIG. An oil pan 23 is attached to the lower portion of the cylinder block 22. In addition, the cylinder block 22 has eight cylinders 1, 2, ...
Three, four, five, six, seven, and eight holes are bored, and eight cylinder heads are arranged on the upper surface of the cylinder block 22. And each cylinder 1, 2, 3, 4, 5, 6, 7
An exhaust manifold is continuously provided at the exhaust port of 8, and the exhaust from each cylinder is collected by the inner merging manifold A and the outer merging manifold C and supplied to the turbine 26 of the supercharger. Due to the rotation of the turbine 26 of the supercharger,
The blower 27 of the supercharger is rotated, the mixer of air and fuel gas is compressed, cooled by the air cooler 28, and then supplied into the cylinders 1, 2, 3, 4, 5, 6, 7, and 8. There is. The exhaust gas that has rotated the turbine 26 of the supercharger is the exhaust port 24.
Emitted from.

In the gas internal combustion engine as described above, the present invention follows the change in the ignition sequence of the cylinders in order to minimize the torsional vibration when the rated rotation of the internal combustion engine is changed. Then, it is possible to change to a group configuration of exhaust manifolds with the least exhaust interference.

As an example, FIG. 1 shows an internal combustion engine for a 50 Hz generator, and the ignition sequence is 1 → 2 → 4 → 6 → 8 → 7 →
The case of 5 → 3 is shown. In this way, by setting the ignition sequence to, for example, 1 → 2 → 4 → 6 → 8 → 7 → 5 → 3, as shown in FIG. 10, 1500 rpm, which is the rotational speed of the internal combustion engine for obtaining an alternating current of 50 Hz. The torsional vibration at the time of can be minimized. When the ignition order is determined in this way, the exhaust manifold group configuration that can minimize the exhaust interference is 1-4-5.
Collect -8 as a set in the outer merging manifold C, and 2-3.
Optimally, a set of -6-7 is collected in the inner confluence manifold A.

On the contrary, in the case of an internal combustion engine for a 60 Hz generator, the number of revolutions is desired to be 1800 revolutions. At 1800 revolutions, the torsional vibration is the smallest, as shown in FIG. 1 → 3 → 7 → 5 → 2 → 4 → 8 →
The torsional vibration generated at 6 is the smallest at 1800 rotations. In this way, set the ignition order to 1
When → 3 → 7 → 5 → 2 → 4 → 8 → 6, exhaust interference occurs in the exhaust manifold group configuration shown in FIG. 1, so the group needs to be changed. In this case, it is optimal to join 1-2-7-8 with the inner merging manifold A and join 3-4-5-6 with the outer merging manifold C as shown in FIG.

Even in the same internal combustion engine, when the ignition order is changed, the exhaust manifold can be easily replaced by changing the group configuration in order to reduce exhaust interference. That is, in the present invention, the exhaust manifolds are the inner merging manifold A, the outer merging manifold C, the two exhaust manifold B.
It is divided into B ′, one exhaust port manifold D and D ′, and a connecting pipe 12. A flexible connecting pipe 15 is provided in a portion connecting the inner merging manifold A and the two exhaust manifolds B and B ', and the outer merging manifold C and the one exhaust manifold D and D'. The connection pipe 12 is provided in the case where the 2 exhaust port manifolds B and B'and the 1 exhaust port manifolds D and D'are far away from the inner merging manifold A and the outer merging manifold C. The connection pipe 1
2 uses the connecting pipe 11 having a short length when the exhaust manifold is converted as shown in FIG.

In FIG. 1, the cylinder 1-4-5-8 is constructed so as to merge with the outer merging manifold C, and the cylinder 1 is mounted with the bracket of the one exhaust manifold D'and is connected to the cylinder 4. 5 is an outer merging manifold C
The brackets 19 and 18 integrally formed with the cylinder 8 are connected to each other.
I am wearing. Also, each exhaust bracket of the 2 exhaust port manifold B'is attached to the cylinders 2 and 4, and the bracket 17 of the 2 exhaust port manifold B is attached to the cylinders 6 and 7.
・ I am wearing 16.

The 2 exhaust port manifold B'and the 2 exhaust port manifold B are connected to the flexible connecting pipes 15, 15.
And the 1-exhaust manifold D'and the 1-exhaust manifold D by fitting the connecting pipes 12 and 12 and the flexible connecting pipes 15 and 15 to the exhaust manifold, Connected with. The inner merging manifold A and the outer merging manifold C are connected to a turbine 26 of the supercharger.

In FIG. 2, the cylinders 1 and 2 have two
The exhaust port manifold B ′ is connected, the two exhaust port manifolds B ′ are connected to the cylinders 7 and 8, and the two exhaust port manifolds B ′ and the two exhaust port manifolds B are connected pipes 11.1.
1 and flexible connecting pipes 15 and 15 are connected to the inner merging manifold A. The cylinder 3 is equipped with one exhaust port manifold D ′, and the cylinder 6 is equipped with one exhaust port manifold D ′. The first exhaust port manifolds D ′ and D and the flexible connection pipes 15 and 15 are connected to the outer merging manifold C.
The cylinders 4 and 5 are equipped with brackets 19 and 18 integrally formed with the outer merging manifold C.

As shown in FIGS. 3 and 4, the inner merging manifold A and the outer merging manifold C merge at the inlet of the turbine 26 of the supercharger, and after driving the turbine 26 of the supercharger by exhaust gas, It is discharged from the exhaust port 24. Further, the gas fuel is supplied from the gas fuel supply pipe 30 to the inlet side of the blower 27 of the supercharger, compressed by the blower 27 of the supercharger, and then compressed and mixed with the fuel gas and the air. Cooler 28 to cylinder 1
-Supplied to the air supply ports of 2, 3, 4, 5, 6, 7, 8.

In FIG. 5, the outer merging manifold C
Shows the configuration of. The merging port 14a of the outer merging manifold C is connected to the merging port 13d of the inner merging manifold A. Further, in the outer merging manifold pipe 14,
The manifolds 19 and 18 are integrally formed, and the connection ports 14c and 14b for mounting the flexible connection pipe 15 are formed. The outer merging manifold pipe 14 and the manifolds 19 and 18 constitute an outer merging manifold C.

In FIG. 6, the inner merging manifold A
Is shown. The inner merging manifold A is composed of an inner merging manifold pipe 13 and a flexible connecting pipe 15, and the inner merging manifold pipe 13 includes:
A converging port 13d for coupling the converging port 14a of the outer merging manifold C, a coupling port 13a for coupling to the exhaust inflow port of the turbine 26 of the supercharger, and coupling ports 13c and 13b for coupling the manifold by the flexible coupling pipe 15. It is configured.

In FIG. 7, the two exhaust port manifold B
The second exhaust port manifold B is integrally formed with the manifolds 17 and 16. FIG. 8 shows the one exhaust manifold D. A manifold 20 is formed in the one exhaust port manifold D. The connecting pipe 12 is shown in FIG. In addition to the connection pipe 12, in the case of FIG. 2, a short connection pipe 11 is used.

[0022]

Since the present invention is constructed as described above, it has the following effects. That is, firstly, the conventional 8
In the case of an internal combustion engine with cylinders, when manifolds are not grouped and exhaust gases from all cylinders are combined, the capacity of the manifolds is configured to be as large as possible so that adverse effects due to exhaust gas interference do not occur. In this case, dynamic pressure supercharging cannot be performed and static pressure supercharging is performed.Therefore, it is highly efficient and expensive so that the supercharger can be driven even with static pressure supercharging. It needs a feeder. On the other hand, in the case of the present invention, the exhaust manifolds are configured as a group, and the exhaust manifolds of each group are configured so that exhaust interference is minimized. Therefore, the dynamic pressure supercharging system in which the capacity of the manifold is reduced Therefore, the supercharger of the dynamic pressure supercharger can be a low cost and low efficiency supercharger.

Secondly, since the exhaust manifold has a group structure, it is possible to avoid exhaust interference, and it is not necessary to increase the capacity of the manifold in order to avoid exhaust interference as in the conventional case. is there. This made it possible to reduce the diameter of the manifold and also reduce the vertical width of the exhaust manifold portion.

Thirdly, by dividing the exhaust manifold into an inner merging manifold A, two exhaust manifolds B and B ', an outer merging manifold C, and one exhaust manifold D and D', a group-structured exhaust manifold can be easily constructed. It could be configured and had a simple structure and could be easily maintained.

Fourth, in the case of an internal combustion engine for a generator,
The desired number of revolutions is 150 in the 50Hz and 60Hz regions.
Different from 0 rotation and 1800 rotation, in order to make an internal combustion engine with the least torsional vibration in this rotation, it is necessary to change the ignition order. If the ignition order is changed, the group structure is changed in order to reduce exhaust interference. 1-4-5-8 and 2-3-
It is necessary to change from 6-7 to 1-2-7-8, 4-5-6-7, etc., but the change in this case is to change the inner merging manifold A and the two exhaust port manifolds B and B '. And the outer merging manifold C and the one exhaust port manifolds D and D'can be easily replaced.

Fifth, in the design of an internal combustion engine, the ignition order may be changed in order to optimize the crankshaft strength and the metal surface pressure, which are major design factors, but in such a case as well. , The group configuration of the exhaust manifold can be changed.

[Brief description of drawings]

FIG. 1 is a front view of an internal combustion engine showing an exhaust manifold when a group configuration of 1-4-5-8 and 2-3-6-7 is shown.

FIG. 2 is a front view of an internal combustion engine showing an exhaust manifold when a group configuration of 1-2-7-8 and 4-5-6-7 is shown.

FIG. 3 is a side view of the internal combustion engine showing portions of a supercharger and an exhaust manifold.

FIG. 4 is an enlarged view of a connecting portion between an exhaust manifold and a supercharger.

FIG. 5 is a front view of an outer merging manifold C.

FIG. 6 is a front view of an inner merging manifold A.

FIG. 7 is a front view of a 2-exhaust port manifold B.

FIG. 8 is a front view of one exhaust port manifold D.

9 is a front view of the connecting pipe 12. FIG.

FIG. 10 is a drawing showing torsional vibration in the case of 50 Hz / 1500 rated rotation.

FIG. 11 is a diagram showing torsional vibration in the case of 60 Hz / 1800 rotation.

[Explanation of Codes] 1, 2, 3, 4, 5, 6, 7, 8 Cylinder A Inner merging manifold B, B'2 Exhaust outlet manifold C Outer merging manifold D, D'1 Exhaust outlet manifold

Claims (1)

[Claims] 1. In a dynamic pressure supercharging internal combustion engine equipped with a single supercharger with in-line 8 cylinders, an exhaust manifold, an inner merging manifold, an outer merging manifold, two exhaust manifolds, and one exhaust outlet An exhaust manifold structure for a dynamic pressure supercharged engine, comprising a manifold, which can be changed to a group structure that avoids exhaust interference when the ignition order of the internal combustion engine is changed.