JPH0121141Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention purifies the exhaust gas by switching the flow of exhaust gas between the flow through the turbo supercharger and the flow through the bypass passage. This invention relates to an exhaust gas turbocharging device that guides the exhaust gas toward the device.

(Prior Art) Conventionally, an exhaust gas turbocharger has an exhaust gas inlet and an exhaust gas outlet of a turbocharger in an exhaust gas passage, as disclosed in, for example, Japanese Utility Model Application Publication No. 15428/1983. A bypass passage for bypassing is provided, and a bypass valve for opening and closing the bypass passage is provided in the exhaust gas passage, and the bypass valve is opened and closed to change the flow of exhaust gas to the flow via the turbo supercharger and the turbo supercharger. A configuration is known in which the exhaust gas is switched to flow both through the exhaust gas and the bypass passage, and the exhaust gas is guided toward the exhaust gas purification device.

In addition, as an improved version of the exhaust gas turbocharging device, as shown in Japanese Patent Application Laid-open No. 155310/1984, a bypass valve consisting of one valve body is rotatably provided in the exhaust gas passage, and the bypass valve It is known that the exhaust gas outlet of the turbocharger and the downstream opening of the bypass passage are selectively opened and closed in accordance with the rotation of the turbocharger. In this case, by driving the bypass valve using one driving source (actuator), the flow of exhaust gas can be switched between the flow through the turbocharger and the flow through the bypass passage. Therefore, in this exhaust gas turbocharger, the drive source can be maintained as one as before, which can suppress the increase in cost, and the flow of exhaust gas can be changed between the flow through the turbocharger and the bypass passage. Since the flow can be selectively switched to the flow through the turbocharger, the driving efficiency of the turbocharger can be increased, and when the flow is through the bypass passage, the exhaust gas can be directly switched to the exhaust gas in a high temperature state. This means that it can be introduced into a purification device to promote chemical reactions and increase its purification efficiency.

However, in reality, the valve body, exhaust gas passage, etc. of the bypass valve mentioned above are manufactured with variations in dimensions during manufacturing, etc., and the exhaust gas outlet of the turbocharger and the downstream opening of the bypass passage are It has become difficult to airtightly close the two valves with a bypass valve consisting of a single valve body. Therefore, when the exhaust gas flow is selected to flow through the turbo supercharger, the exhaust gas leaks through the bypass passage into the exhaust gas passage downstream of the exhaust gas outlet of the turbo supercharger. If the drive efficiency of the turbocharger cannot be sufficiently increased, and if the flow of exhaust gas is selected to flow via the bypass passage, the exhaust gas will leak through the turbocharger and the exhaust gas purification will be difficult. This makes it impossible to sufficiently increase the purification efficiency of the device.

(Purpose of the invention) The present invention was made in view of the above-mentioned circumstances, and its purpose is to sufficiently increase the driving efficiency of the turbocharger when generating a flow of exhaust gas via the turbocharger, and to bypass the bypass. An object of the present invention is to provide a bypass valve device for an exhaust gas turbocharger that can sufficiently increase the purification efficiency of the exhaust gas purification device when causing exhaust gas to flow through a passage.

In order to achieve this object, the present invention provides an exhaust gas passage provided with a bypass passage that bypasses an exhaust gas inlet and an exhaust gas outlet of a turbocharger, and a downstream opening of the bypass passage and the turbocharger. A bypass valve is provided that opens and closes the exhaust gas outlet of the turbocharger, and switches the flow of exhaust gas between the flow of exhaust gas via the turbocharger and the flow of exhaust gas via the bypass passage. In an exhaust gas turbocharger device that guides gas toward an exhaust gas purification device, the bypass valve includes an exhaust gas outlet opening/closing valve body that opens and closes the exhaust gas outlet, and a bypass passage opening/closing valve that opens and closes a downstream opening of the bypass passage. and the bypass passage opening/closing valve body is supported by the exhaust gas outlet opening/closing valve body so as to be movable relative to the exhaust gas outlet opening/closing valve body. It is configured as a bypass valve device for the supply device.

With the above-mentioned configuration, it is possible to drive the bypass valve consisting of the exhaust gas outlet opening/closing valve body and the bypass passage opening/closing valve body with one driving source, and it is also possible to drive the bypass passage opening/closing valve body as the exhaust gas outlet opening/closing valve body. Since the valve body is configured to be movably supported against the exhaust gas outlet, if the valve body is arranged to match the exhaust gas outlet of the turbocharger with reference to the exhaust gas outlet opening/closing valve body, the bypass With respect to the passage opening/closing valve body, the above-mentioned dimensional variations can be compensated for by its movability, and the bypass passage opening/closing valve body can be provided so as to be adaptable to the downstream opening of the bypass passage.

Therefore, both of the above valve bodies can ensure high airtightness when closed, and even if the flow of exhaust gas is selected to be either through the turbo supercharger or through the bypass passage, Exhaust gas will no longer leak from the other side.

Moreover, in the above configuration, instead of movably supporting the exhaust gas outlet opening/closing valve body with respect to the bypass passage opening/closing valve body, the bypass passage opening/closing valve body is movably supported with respect to the exhaust gas outlet opening/closing valve body. Therefore, the airtightness (sealing performance) of the bypass passage opening/closing valve body with respect to the downstream opening of the bypass passage will not deteriorate due to the accumulation of impurity particles in the exhaust gas or thermal effects, and the closing of the bypass passage opening/closing valve body will not deteriorate. This means that airtightness can be maintained for a long period of time.

As a result, when generating a flow of exhaust gas via the turbocharger, the driving efficiency of the turbocharger can be sufficiently increased over a long period of time, and the flow of exhaust gas is generated via the bypass passage. In some cases, the purification efficiency of the exhaust gas purification device can be sufficiently increased.

(Example) Hereinafter, an example of a bypass valve device for an exhaust gas turbocharger according to the present invention will be described based on the drawings.

In the figure, 1 is a turbo supercharger body, 2 is a supercharging passage, and the downstream side of the supercharging passage 2 is connected to an intake passage 3 of the engine body (not shown). An intercooler 4 is provided in the middle, and a throttle valve 5 is provided on the downstream side of the intercooler 4 upstream of the intake passage 3, and the supercharged air is cooled by the intercooler 4 and sent to the intake passage 3. 6 is a control unit.

The turbocharger main body 1 is provided with an exhaust gas passage unit 7. Here, the exhaust gas passage unit 7 is integrated with an exhaust gas manifold, and is connected to a downstream exhaust gas passage 8 and an upstream exhaust gas passage 9. have. In this downstream exhaust gas passage 8,
An exhaust gas purification device 10 is installed on the downstream side thereof, and a three-way catalyst or the like is used in this exhaust gas purification device 10. This exhaust gas purification device 1
An oxygen sensor 11 is provided immediately upstream of the oxygen sensor 0. The downstream exhaust gas passage 8 and the upstream exhaust gas passage 9 are communicated with each other by a bypass passage 12, and a valve seat 13 is provided at the downstream opening end of the bypass passage 12.
is provided. The upstream opening end of the downstream exhaust gas passage 8 is an exhaust gas outlet joint surface 16 that is joined to a joint surface 15 on the exhaust gas outlet side of the pipe line 14 connected to the turbocharger main body 1. The surface 16 is configured to also serve as a valve seat. The upstream exhaust gas passage 9 has an exhaust gas inlet joint surface 18 that is joined to the joint surface 17 on the inlet side of the turbocharger body 1, and the upstream exhaust gas passage 9 allows exhaust gas to pass through the turbocharger body 1. The exhaust gas can be sent toward the exhaust gas purification device 10, and the exhaust gas can be bypassed without passing through the turbocharger main body 1 and sent toward the exhaust gas purification device 10.

A bypass valve 19 is provided in the downstream exhaust gas passage 8, as shown in an enlarged view in FIG.
This bypass valve 19 has a function of switching the flow of exhaust gas between the flow of exhaust gas via the turbo supercharger and the flow of exhaust gas via the bypass passage, 20 is an actuator for driving the bypass valve, and 21 is an actuator for driving the bypass valve. A three-way solenoid valve for driving the actuator is shown, and 22 is the actuator 2.
0 drive rod. The bypass valve 19 is
It is composed of a valve body 23 and a valve body 24, and the valve bodies 23 and 24 are made of metal. Valve body 23
The valve body 24 has the function of seating on and off from the joint surface 15 on the exhaust gas outlet side of the pipe line 14 to open and close the upstream opening end of the downstream exhaust gas passage 8, and the valve body 24 sits on and off from the valve seat 13 to open and close the upstream opening end of the downstream exhaust gas passage 8. It has the function of opening and closing the passage 12.

The valve body 24 is generally composed of a valve portion 25 and a pin 26, and the valve body 23 is formed with an insertion hole 27 through which the pin 26 is inserted. This insertion hole 27
The pin 26 is configured to extend in the thickness direction of the valve body 23 and pass through the valve body 23, and the diameter of the pin 26 is smaller than that of the insertion hole 27, so that the valve body 24 is inserted into the valve body 23. It is swingably supported by 23, and 28 is a washer to prevent it from falling off.

The bypass valve 19 closes the upstream opening end of the downstream exhaust gas passage 8 to bypass the exhaust gas when the engine is in a cold state. The valve body 31 of the three-way solenoid valve 21 is communicated with the three-way solenoid valve 21 through the communication passages 29 and 30, and is controlled based on the engine cold state signal from the control unit 6.
, the intake negative pressure on the downstream side of the throttle valve 5 is applied to the actuator 20, and the bypass valve 19 is operated in a direction to close the upstream opening end of the downstream exhaust gas passage 8. Here, an orifice 32 is provided in the middle of the communication passage 29, and when the engine is cold, the bypass valve 19 is activated due to a sudden change in the intake negative pressure due to sudden opening/closing of the throttle valve 5 during acceleration, etc. The bypass valve 19 is prevented from actuating suddenly.
Furthermore, the durability and operational performance of the actuator 20 are guaranteed. Incidentally, instead of providing the orifice 32, a check valve may be provided in the communication passage 29.

After the engine warms up, the intake pressure on the upstream side of the throttle valve 5 is applied to the actuator 20 by the three-way solenoid valve 21, and the bypass passage 12
The downstream end of the valve is closed.

The valve body 23 closes the exhaust gas outlet of the turbocharger when the exhaust gas is flowing through the bypass passage, and the valve body 24 closes the exhaust gas outlet of the turbocharger when the flow through the turbocharger is occurring. It closes the passage 12, and FIGS. 1 and 2 show a state in which the valve body 23 closes the exhaust gas outlet of the turbocharger and exhaust gas flows through the bypass passage. When switching from the flow of exhaust gas via the bypass passage to the flow of exhaust gas via the turbocharger, the actuator 20 is operated to rotate the bypass valve 19 in the direction of arrow A. . At this time, since the valve body 24 is movably supported by the valve body 23, it is brought into close contact with the valve seat 13 along the seat surface of the valve seat 13, and the bypass passage 12 is sealed, so that the turbo supercharger This prevents the exhaust gas from leaking into the downstream exhaust gas passage 8 via the bypass passage 12 when the exhaust gas is flowing through the bypass passage 12.

Here, since there is a gap between the insertion hole 27 of the valve body 23 and the pin 26 of the valve body 24, in the case of this embodiment, when the exhaust gas is flowing through the bypass passage, It is possible that exhaust gas leaks from the exhaust gas outlet of the turbo supercharger through this gap, but since the turbo supercharger itself functions as an air resistance element, this leakage is considered to be negligible. It will be done.

In FIG. 1, 33 is an actuator for driving the waste gate valve, 34 is its driving rod, and in FIG. 2, 35 is a sealing member.

FIG. 3 shows another embodiment according to the present invention, in which a pin 26 is embedded and fixed in the valve body 23, the valve body 24 is composed only of the valve part 25, and a recess 37 is formed in the pin 26. The valve portion 25 is movably supported by the pin 26.

(Effects of the invention) As described above, the present invention is capable of sufficiently increasing the drive efficiency of the turbocharger over a long period of time when generating a flow of exhaust gas through the turbocharger, and by bypassing the turbocharger. When the exhaust gas is caused to flow through the passage, the purification efficiency of the exhaust gas purification device can be sufficiently increased.

Moreover, the structure of the bypass valve is simple, and its manufacture can be facilitated.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a bypass valve device for an exhaust gas turbocharging device according to the present invention. FIG. 2 is an enlarged view of the main parts of the bypass valve device according to the present invention. FIG. 3 is an embodiment diagram showing another configuration of the bypass valve according to the present invention. DESCRIPTION OF SYMBOLS 1...Turbocharger main body, 7...Exhaust gas passage unit, 8...Downstream exhaust gas passage, 9...Upstream exhaust gas passage, 10...Exhaust gas purification device, 12
... Bypass passage, 13 ... Valve seat, 16 ... Exhaust gas outlet joint surface, 18 ... Exhaust gas inlet joint surface,
19... Bypass valve, 20... Actuator, 23, 24... Valve body.

Claims (1)

[Claims for Utility Model Registration] In an exhaust gas passage provided with a bypass passage that bypasses the exhaust gas inlet and exhaust gas outlet of the turbocharger, the downstream opening of the bypass passage and the exhaust gas of the turbocharger are connected. A bypass valve is provided that opens and closes the outlet, and switches the flow of exhaust gas between the flow of exhaust gas via the turbo supercharger and the flow of exhaust gas via the bypass passage, and transfers the exhaust gas to the exhaust gas purification device. In the exhaust gas turbocharger device, the bypass valve is configured with an exhaust gas outlet opening/closing valve body that opens and closes the exhaust gas outlet, and a bypass passage opening/closing valve body that opens and closes a downstream opening of the bypass passage, A bypass valve device for an exhaust gas turbocharger, wherein the bypass passage opening/closing valve body is supported by the exhaust gas outlet opening/closing valve body so as to be movable relative to the exhaust gas outlet opening/closing valve body. .