JPS5922253Y2 - Internal combustion engine turbocharger - Google Patents

Description

[Detailed Description of the Invention] In an internal combustion engine equipped with a turbocharger, the output is increased by supercharging, but the fuel consumption rate gradually worsens as the engine reaches higher speeds.

This deterioration in fuel consumption can be avoided by providing a wastegate to increase the amount of exhaust gas that does not pass through the exhaust turbine as the speed increases.

The purpose of the present invention is to avoid the deterioration of the fuel consumption rate described above without providing a wastegate, and the present invention will be explained with reference to the drawings as follows.

In FIG. 1, CH is a cylinder head, EM is an exhaust manifold, and TB is an exhaust turbine.

In this proposal, the exhaust manifold EM and exhaust turbine T
In the exhaust conduit ED between B and B, a bimetallic device BM is provided which throttles the exhaust flow.

2 and 3 are drawings illustrating a bimetal device BM, in which the bimetal device BM shown in FIG. 2 is provided with four bimetal leaves BL whose base ends are supported by a ring RG, and the device shown in FIG. , the inner circumferential surface W of the exhaust pipe ED
Four bimetal leaves BL are provided whose intermediate portions are supported by L via springs SP.

The bimetal device BM increases the effective cross-sectional area of the exhaust conduit ED as the load shifts from low to high (as the exhaust temperature increases).

This system reduces fuel consumption by changing the conditions for introducing exhaust gas into the exhaust turbine TB (velocity distribution and expansion state of the exhaust flow) during high and medium loads when the fuel consumption rate deteriorates due to the installation of a turbocharger. (a) At low loads, the effective cross-sectional area of the exhaust pipe ED is set such that exhaust energy is used effectively for supercharging. (b) provide the exhaust conduit ED with an effective cross-sectional area that limits the degree of increase in backpressure as the load increases (particularly from medium to high loads approaching high loads);

In terms of efficiency of the exhaust turbine TB, the term a is a state in which the exhaust turbine TB operates with high efficiency, and the above term is a state in which the exhaust turbine TB operates with low efficiency.

In other words, the above-mentioned state is a state in which an effect similar to that of a waste gate is brought about, in which a portion of the exhaust gas is passed in a bypass manner while increasing in amount as the load increases.

As mentioned above, this proposal focuses on the efficiency of the exhaust turbine and introduces a bimetal device as a factor to reduce the efficiency appropriately when shifting to a high load direction. It can be constructed without complicating the pipe system like the conventional one.

[Brief explanation of drawings]

FIG. 1 is an overall view of the turbocharger according to the present invention, and FIGS. 2 and 3 are drawings illustrating the bimetal device shown in FIG. 1. CH...Cylinder head, EM...Exhaust manifold, TB...Exhaust turbine, BM...
...Bimetal device, RG...Ring,
BL...Bimetal leaf, ED...
Exhaust pipe, WL... Inner peripheral surface of exhaust pipe, SP.
...Spring.

Claims (1)

[Scope of utility model registration request] A bimetal device BM that throttles the flow of exhaust gas is provided inside the exhaust conduit ED between the exhaust turbine TB that drives the compressor and the exhaust manifold EM, and the bimetal device BM has a cross-sectional area of the exhaust flow path that reduces the cross-sectional area of the exhaust flow path as the exhaust temperature increases. A turbocharger for an internal combustion engine, characterized in that it has increased characteristics.