JPS6275026A - Device for driving waist gate of turbocharger - Google Patents

Abstract

PURPOSE:To attenuate the vibrating operation of an actuator by providing a throttle passage in which the ratio L/D of its length L to its inside diameter D, is 70 or above, on a pressure transmitting passage, and attenuating a pressure wave on an intake side in a process of being transmitted to said actuator through said pressure transmitting passage. CONSTITUTION:When an exhaust energy increases, increasing the speed of rotation of a turbine 8, and as a supercharging pressure discharged from a compressor 9 becomes above a set value, a diaphragm 35 is displaced against a spring 37 due to pressure in a pressure introducing chamber 36, in an actuator 32, opening a waist gate valve 26. A pressure transmitting passage 38 is formed by connecting a small-diameter pipe 39 which is connected to the pressure introducing chamber 36 of the actuator 32, to a small-diameter pipe 41 which is connected to the discharge port 18 of the compressor 9. via a connecting pipe 42, and the inside of the small-diameter pipe 41 serves as a throttle passage 43. The throttle passage 43 has a length L of 200mm and an inside diameter D of 2mm, and their ratio L/D=100, indicating a valve above 70.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wastegate drive device used in conjunction with a turbocharger installed in an engine manufactured by Ichikawa Motor Co., Ltd., etc.

[Conventional technology 1] Modern automatic Ogawa engines use the energy of 1J gas to rotate a turbine.

A turbocharger is often used in which the rotational force of the turbine drives a compressor to supply air under pressure into a cylinder.

In such a turbocharger, a turbine bypass path is provided for the turbine, and this bypass path is opened and closed by a wastegate pulp to regulate the maximum boost pressure at a constant level. is common.

However, in such a device, for example, an actuator that operates by being energized by the pressure introduced into the pressure introduction chamber;
A wastegate drive device consisting of a pressure transmission path that guides the pressure on the compressor discharge side of the turbocharger to the pressure introduction chamber of the actuator, and a displacement transmission mechanism that transmits the output displacement of the actuator to the wastegate valve. has been established. When the pressure on the outlet side of the compressor reaches a set value, the actuator operates to open the wastegate valve, reducing the exhaust energy supplied to the turbine and preventing the boost pressure from becoming excessive. Now you get 11-shi defense.

However, in such a configuration, pressure waves of exhaust gas generated by opening and closing of the exhaust pulp of the engine are periodically applied to the wastegate valve, and pressure waves of exhaust gas generated by opening and closing of the intake valve are applied to the pressure introduction chamber of the actuator. The pressure waves generated by this are transmitted through the intake system piping. Therefore, there is a problem in that vibrations are induced in the actuating rod of the actuator, the displacement transmission mechanism provided between the actuator and the waste gate valve, and other parts are likely to be damaged.

In particular, when a link-type displacement transmission mechanism is used, the vibrations generated by the pressure waves are applied to the link member, causing significant damage and wear to the pin shaft provided at the connecting part of the link member. becomes. Therefore,
Unless special measures are taken, such as selecting and using special materials, looseness will occur in the link member connection area, impairing the sealing of the wastegate valve, and gradually reducing the performance of the turbocharger. This can easily lead to the inconvenience of doing so.

As a prior art related to the wastegate drive device, as disclosed in Japanese Utility Model Application Publication No. 58-35620, the pressure introduction chamber of the actuator is connected to the compressor discharge side of the turbocharger via a pressure transmission path having a restriction. Some are designed to connect. Only 1. Therefore, the throttle is provided to slightly extend the supercharging pressure transmitted to the pressure introduction chamber of the actuator,
As will be described later, the ratio of length to inner diameter, 17, is an extremely small value. Therefore, with such a device, it is not possible to effectively prevent the above-mentioned intake pressure wave from being transmitted to the actuator.

[Problem 1 to be Solved by the Invention] As described in 1-1 below, the present invention is based on the idea that a pressure wave is transmitted to an actuator that is activated by the pressure on the discharge side of a compressor, and the output displacement of this actuator is controlled by a waste gate. The purpose is to effectively eliminate the problem of damage and severe wear to the displacement transmission mechanism for transmitting data to the valve, wastegate valve, etc.

Means for Solving Problem E 1 In order to achieve the above object, the present invention provides an actuator that operates by being energized by the pressure introduced into the pressure introduction chamber;
The actuator is equipped with a pressure transmission path that introduces the pressure on the compressor discharge side of the turbocharger into the pressure introduction chamber of the actuator, and a displacement transmission mechanism that opens and closes a wastegate valve provided in a turbine bypass path of the turbocharger using the output of the actuator. The wastegate drive device is characterized in that the pressure transmission path is provided with a throttle passage in which the ratio of the length L to the inner diameter is 7 or more.

[Operation 1] According to such a configuration, the pressure wave on the intake side is effectively weakened in the process of being transmitted to the actuator through the pressure transmission path, so that the vibrational operation of the actuator is suppressed. That is, the pressure loss between the inlet and outlet in the throttle passage is 2g. Here, Pl, inlet [1 pressure, P2.outlet [l pressure L; passage length,
D: Passage inner diameter entry; coefficient of friction; Wl; flow velocity on the inlet side; g; gravitational acceleration. Therefore, it can be seen that in order to increase the pressure loss PI-P2, it is better to increase L/mouth. In the conventional one, the 7 ports are about 10 to 30, but in the present invention, this ratio is set to 17 ports, which is 70 or more -L. As a result of various experiments, we found that if the ratio 17 is set to 70 or more, the pressure wave transmitted to the actuator will be reduced even when used in a two- or three-cylinder engine with large intake pulsation. It has been proven that even if the displacement transmission mechanism is constructed using ordinary materials, there will be no performance deterioration due to breakage or itching within the service life of an automatic type.
It's happening. In other words, according to the configuration of the present invention, it is possible to effectively suppress generation of vibrations large enough to cause damage or wear to each member of the displacement transmission mechanism, the wastegate valve, and the like.

[Example 1 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the figure, 1 is a three-cylinder engine made by Ichikawa Automobiles, 2 is a combustion chamber of this engine, 3 is a piston, 4 is an intake valve, 5 is an exhaust valve, and 6 is a capretor.

Further, 7 is a turbocharger attached to this engine l. The turbocharger 7 includes a turbine 8 and a compressor 9 driven by the turbine 8. The turbine 8 has an inlet r'l l and an outlet 12
The impeller 14 is housed in a casing 13 having a casing 13, and its inlet 11 communicates with the combustion chamber 2 of the engine l via an exhaust pipe 15 and an exhaust valve 15, and its outflow rl Reference numeral 12 indicates a device that is opened to the atmosphere via a catalytic converter, a muffler, etc. (not shown). On the other hand, the compressor 9 houses an impeller 21 directly connected to the blades of the turbine 8 in a casing 19 having a suction 1117 and a discharge port 18, and the suction 1117 is connected through an air cleaner (not shown). It is opened to the atmosphere, and its discharge 1-11
8 communicates with the combustion chamber 2 via an intake pipe 22, a carburetor 6, and an intake valve 4.

Further, this turbocharger 7 is provided with a turbine bypass passage 25 that bypasses the turbine 8, and this bypass passage 25 is provided with a wastegate valve 26. This wastegate valve 26 is opened and closed by a wastegate drive device M31.

This wastegate drive device 131 is a compressor 9
The actuator 32 is actuated by the pressure on the discharge side of the
and a displacement transmission mechanism 33 that opens and closes the waste gate valve 26 by the output displacement of the actuator 32. The actuator 32 is the actuating rod 3
A diaphragm 35 supporting 4 and this diaphragm 3
5, and a spring 3 that presses the diaphragm 35 toward the pressure introduction chamber 36.
7 and J41i, so that when the supercharging pressure introduced into the pressure introduction chamber 36 exceeds the set value by L, the diaphragm 35 is displaced forward and the actuating rod 34 protrudes. It has become. Thus, this pressure introduction chamber 36 is connected to the compressor 9 via a pressure transmission path 38.
The discharge port 18 is connected to the discharge port 18. The pressure transmission path 38 connects a thin tube 39 connected to the pressure introduction chamber 36 of the actuator 32 and a thin tube 41 connected to the discharge port 18 of the compressor 9 via a connecting tube 42.
The inside of the thin tube 41 serves as a throttle passage 43 according to the present invention. That is, this throttle passage 43 has a length L of 20
0m Otori, the inner diameter is 21, and the comparison is 7 mouths are 100 and 70
The following shows I9.

On the other hand, the displacement transmission mechanism 38
A first link member 46 connected to the second operating rod 34 via a connecting nut 44.45, and a second link member 48 fixed to the valve body support shaft 47 of the waste gate valve 26 are connected to the bottle shaft 49. The wastegate valve 26 can be urged to the open position when the actuating rod 34 of the actuator 32 is prevented from protruding.

Next, the operation of this embodiment will be explained.

When exhaust gas discharged from the combustion chamber 2 of the engine 1 is supplied to the turbine 8, the turbine 8 rotates at high speed due to the energy contained in the exhaust gas. turbine 8
When the compressor 9 rotates, the compressor 9 is driven to compress the air introduced through the air cleaner and supply it to the combustion chamber 2 of the engine 1. Then, the exhaust energy increases and the turbine 8
When the rotational speed of the compressor 9 increases by 1 and the pressure of the air discharged from the compressor 9, that is, the supercharging pressure, goes around the setting I1, the diaphragm 35 becomes a spring due to the pressure in the pressure introduction chamber 36 of the actuator 32. The actuator 32 is displaced forward against the urging force of the actuator 37, and the actuating rod 34 of this actuator 32 projects forward. As a result, the first link member 46 connected to the actuating rod 34 is connected to the pin shaft 49.
The second link member 48 is urged to rotate in the direction of the arrow X, and the waste gate pulp 26 is opened. In this case, a part of the exhaust gas will be bypassed without passing through the turbine 8, and the turbine power will be increased, thereby suppressing the increase in supercharging pressure.

In this way, it is possible to specify the maximum boost pressure, which is determined by the discharge [11] of the compressor 9.
8 and the pressure introduction chamber 36 of the actuator 32 i!
I! The pressure transmission path 38 to be passed is provided with a throttle passage 43 whose L/port is set to 70 to 1-.

Therefore, by opening and closing the intake pulp 4, the intake pipe 22
Even if a pressure wave is generated within the actuator 32, the pressure wave is effectively prevented from being transmitted to the pressure introduction chamber 36 of the actuator 32.
1- It is possible. Therefore, it is possible to effectively suppress the vibration of the operating rod 34 of the actuator 32 back and forth, and to effectively prevent the pin shaft 49 of the displacement transmission mechanism 33 and the wastegate valve 26 from being damaged or unduly worn. Can defend against 11 points.

FIG. 4 shows that an accelerometer is provided on the operating rod 34 of the wastegate drive device 31 of this embodiment, and that various throttle passages 43 with different L/D are selectively replaced and used. This figure shows the results of successive measurements of the maximum acceleration acting on the As is clear from this figure, when the throttle passage 43 with L/port is 70 is used, an acceleration of 30 g is applied to the operating rod of the 7-cut unit 32 in the operating loft, and L/rl becomes large. The acceleration tends to decrease as the distance increases. If the acceleration acting on the actuating rod 34 is about 30 g or more, as in this embodiment, the displacement of the actuating rod 34 of the actuator 32 is transmitted to the wastegate valve via the link type displacement transmission mechanism 33. 26, there will be no damage or wear to the link members 46, 48, the pin shaft 49 in the connecting portion thereof, or the waste gate valve 26. That is, if the acceleration acting on the actuating rod 34 of the actuator 32 is suppressed to the above value, sufficient durability can be obtained even if the displacement transmission mechanism 33 is constructed using ordinary materials. This eliminates the conventional constraint of having to consider whether or not to take special reinforcing measures, increasing the degree of freedom in design.

In addition, in the following embodiments, a case has been described in which the throttle passage is formed by the thin tube itself, but the present invention is not necessarily limited to this, and a special passage forming member may be provided in the middle of the conduit. It may be provided internally to form a throttle passage.

1 Effects of the Invention 1 Since the present invention has the following configuration, it is possible to effectively prevent vibrations caused in the actuating rod of the actuator, the displacement transmission mechanism provided between the actuator and the waste gate valve, etc. It is possible to eliminate the constraint of requiring reinforcement measures for the displacement transmission mechanism, increasing the degree of freedom in design, and by simplifying the structure and expanding the range of material selection, light oxidation and cost reduction can be achieved. Therefore, it is possible to provide a wastegate drive device that can achieve the following.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a schematic system explanatory diagram showing the entire system, FIG. 2 is a plan view showing the main parts, FIG. FIG. 4 is an explanatory diagram showing the experimental results. l...Engine 4...Intake valve 7...Turbo charge V8.1 Turbine 9...Compressor 25...Bypass passage 26...Wastegate valve 31...Wastegate drive device 32.・Actuator 33 ・Displacement transmission mechanism 34 ・Operating rod 36 ・Haruka introduction chamber 38 ・Pressure transmission path 43 ・・Restriction passage

Claims (1)

[Claims] an actuator that operates by being energized by the pressure introduced into the pressure introduction chamber; a pressure transmission path that introduces pressure on the compressor discharge side of the turbocharger to the pressure introduction chamber of the actuator; and a turbine bypass path of the turbocharger using the output of the actuator. a displacement transmission mechanism for opening and closing a wastegate valve provided in the pressure transmission path, and the pressure transmission path includes a throttle passage having a ratio L/D of length L to inner diameter D of 70 or more. A turbocharger wastegate drive device characterized by: