JPS58214620A - Supercharge pressure controller for internal- combustion engine with supercharger - Google Patents

Abstract

PURPOSE:To improve the engine performance by functioning a waste gate valve through the differential pressure between the supply air and exhaust thus widening the operating area of the waste valve. CONSTITUTION:A waste valve 7 for opening/closing a bypath 6 is functioned by moving a diaphragm 13 in the arrow direction X-Y by means of the differential pressure between the supply air pressure Pa and the exhaust pressure Pg and the spring force of a spring 12 for an actuator 10. Pa and Pg are in such relation as shown by the load-pressure curve for the load of internal- combustion engine. When reversing the functioning direction of Pa and Pg, reverse function is enabled or the waste gate valve 7 can be opened under low Pa.

Description

[Detailed description of the invention] It is related to.

A point to be noted in an internal combustion engine having a supercharger consisting of an exhaust turbine and a compressor driven by the exhaust turbine is that the boost pressure may rise more than necessary due to overspeeding of the supercharger.

In order to solve such problems, as shown in FIG. 1, an exhaust manifold 4 of an internal combustion engine (not shown) has an exhaust turbo type supercharger 6 consisting of an exhaust turbine 1 and a compressor 2 driven by the exhaust turbine 1. In front of the exhaust gas inlet 5 of the exhaust turbine 1, a bypass passage 6 communicating with the outside is provided, and a waste gate valve 7 for opening and closing the bypass passage 6 is provided. An actuator 1 connected to a supply pressure sensing pipe 9 that communicates with an engine intake manifold 8.
When the air supply pressure indicated by arrow A becomes equal to or higher than the opening pressure of the waste gate valve 7, the actuator 1 is activated.

When the waste gate valve 7 is activated, the exhaust gas G is bypassed to the outside via the bypass path 6 as shown by the arrow, thereby preventing an excessive increase in the supply pressure and reducing the maximum in-cylinder pressure of the internal combustion engine from an excessive increase in the cylinder pressure. This prevents the occurrence of lifting and knocking.

Regarding an internal combustion engine equipped with an exhaust turbo supercharger having a bypass passage 6 provided with such a waste gate valve 7, a method according to Japanese Utility Model Publication No. 51-12568 and others has been proposed.
As is well known in 1), the boost pressure control device senses the boost pressure from the compressor 2 of the supercharger (2) and opens and closes the waste gate valve 7. Wastegate Valve 7 Impossible and -d
Chair 1. ) 7 It has the disadvantage that it can only act to open Tobarg 7.

Therefore, the present invention has been made in order to solve the above-mentioned problems of the conventional art. This is intended to improve the engine performance of internal combustion engines with a supercharger by operating the engine's supply air pressure and the differential pressure of the engine, and by removing the waste gate valve. be.

That is, the boost pressure control device for an internal combustion engine of the present invention is an internal combustion engine having a supercharger consisting of an exhaust turbine and a compressor, in which a bypass passage communicating with the outside is provided in front of an exhaust gas inlet of the exhaust turbine, Furthermore, the waste gate valve opens and closes the bypass passage, and the waste gate valve is opened and closed by the differential pressure between the supply air pressure and the exhaust pressure of the internal combustion engine.

Hereinafter, one embodiment of the present invention will not be described with reference to the drawings, but FIG. 2 has a configuration substantially similar to that in FIG. 1 is a schematic layout diagram showing a boost pressure control device for an internal combustion engine, in which the same parts as in FIG. 1 are indicated by the same part numbers.

In this embodiment, a bypass passage 6 communicating with the outside is provided in front of the exhaust gas introduction [] 5 of the exhaust turbine 1 in the same way as in FIG. 1.
The waste gate valve 7 provided in this bypass path B is a supply pressure sensing valve that communicates with the intake manifold 8 that supplies the supply air A pressurized to the supply pressure Pa from the compressor 2 to the internal combustion engine. It is actuated by an actuator 10 having both ends thereof connected to an exhaust pressure sensing vibe 11 which transmits the atmospheric pressure 1)g in the exhaust pipe 9 and the exhaust manifold 4.

That is, in this embodiment, F. ; In an internal combustion engine, the exhaust gas G is transferred as shown by the arrow. 7. The compressor 2 in the same iUI+ is rotated i~, pressurized and air is supplied to the internal combustion engine through the air supply manifold 8 as shown by the arrow A).

Therefore, in the present invention, the pressure difference between the waste gate valve 7 pressure pa that opens and closes the bypass passage 6 and the υ1 atmosphere pressure Pg and the spring force of the spring 12 shown in the actuator 10 in FIG.
This is done by moving the diaphragm 16 in the directions of arrows X-Y.

In FIG. 3, a rubber seal 15 is attached to the sliding portion of the rod 14 that slides in the arrow x-y directions as the diaphragm 13 moves, and that causes the waste gate valve 7 to open and close. has been done.

Here, the supply air pressure p in the internal combustion engine having the supercharger 3
Generally, a and exhaust pressure Pg have a relationship with respect to the load of the internal combustion engine as shown in the load-pressure diagram in Figure 4, but if the directions in which the supply pressure pa and exhaust pressure Pg act are reversed, By doing so, it becomes possible to have a completely opposite effect, that is, to cause the waste gate valve 7 to open when the supply air pressure Pa is low.

Therefore, in a supercharged internal combustion engine to which the boost pressure control device of the present invention is applied, the operation of the waste gate valve that opens and closes the bypass path provided before the exhaust turbine is controlled by the intake pressure and exhaust pressure of the internal combustion engine. By widening the operating range of the wastegate valve, it is possible to improve the performance of the engine.

The present invention can be effectively applied mainly to diesel-type and gasoline-type internal combustion engines having at least one exhaust turbo supercharger.

[Brief explanation of the drawing]

FIG. 1 is a schematic layout diagram showing a conventional boost pressure control device for an internal combustion engine, and FIG. Figure 3 is an enlarged sectional view of the acticoator of Figure 1' and Figure 2, and Figure 41 shows the present invention. It is a car load diagram for an internal combustion engine with a supercharger for purposes of illustration. 1... Loss turbine, 2... Compressor, 3...
・Supercharger, 5...1 loss gas IT+, 6...Bypass path, 7...Wastegate valve pipe, 10...Actuator, 11...Exhaust pressure sensing pipe, 12. ...Spring, 16...Diamond flannel, lea...Air supply pressure, pg...4-
Jl air pressure. Agent Patent Attorney 1: Shin Ogawa - Ben J'll! I-field 11 Kenshobu “111 Kyosaishita Kazuhiko 1st Ward

Claims (1)

[Claims] In an internal combustion engine having a supercharger consisting of an exhaust turbine and a compressor, a bypass passage communicating with the outside is provided before an exhaust gas inlet of the exhaust turbine, and a waste gate valve is provided for opening and closing the bypass passage. 1. A supercharging pressure control device for an internal combustion engine with a supercharger, characterized in that a waste gate valve is opened and closed by a differential pressure between intake pressure and exhaust pressure of the internal combustion engine.