JPS6012888Y2 - Exhaust manifold cooling system for marine engines - Google Patents

Description

[Detailed description of the invention] This invention is a system in which the exhaust manifold of a marine engine is divided into two parts, a manifold body and a connecting member, so that it can be used commonly for supercharged engines and non-supercharged engines.The manifold body and the connecting member are cooled. This invention relates to a cooling device for cooling.

−. Conventional marine engines installed on ships include those equipped with a centrifugal supercharger for supercharging, and those without centrifugal superchargers, which are not equipped with a centrifugal supercharger.Supercharged engines make effective use of exhaust energy. For example, in the case of a four-cylinder engine, the first and fourth cylinders and the second and third cylinders are communicated with each other through these passages, and then the exhaust gas is led to the supercharger, and in the case of a non-supercharged engine, the first and fourth cylinders are communicated with each other through passages. After communicating with the fourth cylinder through one passage, exhaust gas is discharged through an exhaust pipe.

In addition, in order to reduce the overall height of the exhaust manifold of a supercharged engine, the exhaust port is opened at the rear so that exhaust gas can be easily guided to the supercharger installed at the rear of the engine. An exhaust port is opened in the center so that exhaust gas can be efficiently discharged.

For this reason, different exhaust manifolds must be manufactured for each supercharged and non-supercharged engine, which is not only uneconomical, but also: Exhaust manifolds for supercharged engines have complicated shapes, making them difficult to manufacture and expensive. It had some drawbacks, such as being stiff.

In order to overcome this drawback, the present applicant separately proposed a structure in which the exhaust manifold is divided into two parts: a manifold body that can be used in common with supercharged and non-supercharged engines, and a connecting member that can be used only with supercharged engines.

This invention is a cooling device for such a two-part manifold, and aims to improve cooling efficiency and reduce power consumption of the cooling water pump by effectively cooling both parts.

This invention will be described in detail below with reference to an illustrated embodiment.

In the figure, 1 is a water-cooled marine engine body, which has, for example, four cylinders (not shown) inside. It is discharged to manifold 2.

The exhaust manifold 2 consists of a manifold body 4 fixed to the engine body 1 by a fixing member 3, and a connecting member 5 selectively provided on the manifold body 4.

The manifold body 4 has two internal passages 4a and 4b.
One of these passages 4a connects the exhaust ports of the first and fourth cylinders of the engine body 1, and the other 4a connects the exhaust ports of the first and fourth cylinders of the engine body 1.
b communicates with the exhaust ports of the second and third cylinders (both not shown), and these passages 4aw4b
are opened above the manifold body 4 through twenty exhaust ports 6a, 6b provided at the center of the upper surface of the manifold body 4.

Further, a cooling passage 4C is provided around each passage 4-a = 4b, through which the air flows in through a cooling pipe 7 connected to an inlet 41 provided on the upper surface of one end of the manifold body 4. Cooling water is allowed to flow through the passages 4a, 4.
The cooling water that has cooled the cooling water is discharged to the cooling pipe 8 connected to the outlet 42 on the opposite side.

On the other hand, the connecting member 5 provided on the manifold body 4 is
Exhaust port 6a on the top surface of the manifold body 4.

The connecting member 5 has 20 connecting ports 5a at positions that coincide with the connecting ports 6b, and two passages (not shown) communicating with the connecting ports 5a on the ← end side are provided in the connecting member 5.

The other end side of each passage is communicated with a connection port 5b opened on the rear surface of the connecting member 5, and the connection port 5b has two internal parts.
One end of a connecting pipe 10 is connected to the other end of the connecting pipe 10, and the other end of the connecting pipe 10 is connected to the turbine side of a centrifugal supercharger 11 attached to the rear part of the engine body 1. The discharged exhaust gas is guided into the turbine of the centrifugal supercharger 11.

Further, a cooling water passage (not shown) is provided in the connecting member 5 around the passage.1. Two parts of the cooling water separated by a branch joint 12 provided on the cooling pipe 7 are introduced into this first cooling water passage via a flexible joint 13 having an orifice 13a therein.

The flexible joint 13 with internal orifices 1 and 3a is used to arbitrarily set the flow rate of cooling water flowing through the connecting member 5, and those with different opening degrees can be selectively connected according to the required flow rate. has been done.

On the other side of the cooling water passage, the cooling water flowing out from the manifold body 4 through the cooling pipe 8 joins with the cooling water flowing out from the manifold main body 4 through the cooling pipe 8 at a collecting joint 14 provided on the top surface of the connecting member 5, and is then discharged from the cooling pipe 9. It looks like this.

・. Therefore, the connecting member 5 is attached to the engine body 4 equipped with the centrifugal supercharger 11 and used.

As a result, the exhaust gas discharged from the engine body 1 is merged into the first and fourth cylinders and the second and third cylinders in the manifold body 4, and connected through the upper exhaust ports 6a and 6b. The flow flows into the member 5, and further passes through each passage in the connecting member 5 and is connected to the centrifugal supercharger 11 from the connecting pipe 10.
introduced within.

'In the case of soil, the cooling water goes up to the branch joint 12 installed in the pipe line 7 and is diverted, and a part of it flows into the manifold body,
Also, the connecting member 5. A flow rate limited by the orifice 13a flows into the interior to cool both of them, and the already cooled cooling water! After being merged at the collective joint 14, it is discharged through the cooling pipe 29.

In addition, in the case of a non-supercharged engine, an exhaust pipe 15 is connected directly to the exhaust ports 6a and 6b of the manifold body 4 as shown in Fig. 5, and the exhaust gas that has passed through the passages 4a*4b is simultaneously discharged through the exhaust pipe 15. At this time, the cooling water flowing into the manifold main body 4 from the cooling pipe 7 cools the manifold main body 4 and is then discharged from the cooling pipe 9.

1 ・ ・ □This idea, as detailed above, is designed to be used commonly in non-supercharged engines, with an exhaust manifold divided into a manifold body and a connecting member.
By installing an external branch joint and an orifice-free joint near the cooling water inlet, the flow rate of the cooling water flowing between the two can be easily adjusted, thereby preventing overburning of the manifold body and connecting members. Overcooling can be prevented.

In addition, the cooling water passage is simplified, so the flow passage resistance is small.
This increases the flow rate of cooling water, improving cooling efficiency, and since the driving force of the cooling water pump only needs to be small, horsepower consumption can also be reduced.

[Brief explanation of drawings]

The drawings show two embodiments of the invention; Fig. 1 is a side view of the supercharger, Fig. 2 is a rear view, Fig. 3 is a cross-sectional view of the manifold body, Fig. 4 is a plan view of the same, and Fig. 4 is a cross-sectional view of the manifold body. FIG. 5 is a side view of the non-supercharged engine. 1 is the engine body, 2 is the exhaust manifold, 4 is the manifold body, i, 4a't "4b' is the passage, 4.
□ is an inlet, 5 is a connection, member, 12 is a branch joint, 13 is a flexible joint, and 13・a is an orifice.

Claims (1)

[Scope of utility model registration request] An exhaust manifold 2 provided on an engine body 1 to discharge exhaust gas after heat sintering is divided into a manifold body 4 that can be supplied to supercharged engines and non-supercharged engines, and a connecting member 5 that is used only for supercharged engines. , on the side of the cooling water inlet 4□ of the manifold main body and the connecting member 5, there are a branch joint 12 and a collective joint 14 that separate and merge the cooling water to the manifold main body 4 and the connecting member 5, and a flow rate of the cooling water flowing in at least three directions. A cooling device for an exhaust manifold in a marine engine, which is provided with an orifice 13a that limits the flow of air.