JP2504927Y2 - Drive mechanism for waste gate valve for turbocharger - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to transmission of operating force for driving and operating a wastegate valve (generally speaking, an exhaust bypass valve) attached to a turbocharger of an engine. Regarding the mechanism.

[Conventional technology]

FIGS. 5 and 6 exemplify a main part of a conventional drive mechanism, and an arm (not shown) of a wastegate valve.
The shaft 1 connected to the shaft is supported by a bush 2, and one end of a link plate 3 is fixed to the shaft end by means such as caulking 4. A pin 5 is fixed to the other end of the link plate 3 by means such as caulking 6, and a shaft portion 7 of the pin 5 is an actuator (not shown).
The long rod 8 driven by the screw is inserted into the hole 9 at one end, and the E-ring 11 is fitted into the groove 10 of the pin 5 as a pull-out member. (See Japanese Utility Model Laid-Open No. 59-127828, Japanese Utility Model Laid-Open No. 57-13837, Japanese Utility Model Laid-Open No. 61-25540, etc.) [Problems to be Solved by the Invention] This type of drive mechanism includes an exhaust turbine and its Since it is installed in the immediate vicinity of the high temperature part of the exhaust system such as front and rear exhaust pipes, its material is required to have heat resistance and oxidation resistance, and further, the hole 9 of the rod 8 and the shaft portion 7 of the pin 5 Abrasion resistance is also required for sliding parts. Materials that meet this requirement include stainless steel, but any relatively small parts such as the link plate 3, pin 5, E-ring 11, etc.
It is difficult to use stainless steel for large parts such as the rod 8 in terms of material cost and workability. So, in the past, ordinary steel materials were used after heat treatment to increase hardness and plating to increase heat resistance.
It was not sufficient in terms of heat resistance, oxidation resistance, wear resistance and the like.

The present invention provides a drive mechanism that can endure high temperatures without any problems even if a normal steel material that is inexpensive and easy to process is used for large parts such as a rod connected to an actuator. It is a task to be done.

[Means for solving the problem]

The drive mechanism of the wastegate valve according to the present invention has a pin made of stainless steel fixed to the tip of a rod made of steel and connected to an actuator.
The stainless steel pin is rotatably inserted into a hole provided at one end of a link plate made of stainless steel, and the other end of the stainless steel link plate is connected to a waste gate valve. It is characterized in that it is fixed to one end of a driving shaft.

[Action]

Since the present invention has the structure as described in the above section, when the rod is moved in the axial direction by the actuator being biased, the pin fixed to the tip of the rod is attached to one end of the link plate. Since the link plate is rotatably inserted in the provided hole, the link plate rotates about the shaft having the other end fixed, so that the shaft rotates to open / close the wastegate valve. Let In this case, since the part that is slidingly engaged is only between the pin and the hole at one end of the link plate, only these small parts are driven by this type of drive such as heat resistance, corrosion resistance, and wear resistance. It is made of stainless steel that has the performance required for the mechanism, and since the other parts are merely strength members, there is no problem even if it is made of steel material that is cheap and easy to process, and as a result, the entire structure is practically high-grade. The same heat resistance and wear resistance as those made of other materials can be obtained.

〔Example〕

FIG. 1 shows the entire structure of a turbocharger including an embodiment of the present invention, and the essential parts of the embodiment are shown in FIGS. 2 and 3. First, in FIG. 1, 12 is an exhaust turbine (turbine housing), 13 is a charge compressor (compressor housing), 14 is a center housing, 15 is a rotor of a turbine, 16 is an impeller of a compressor, 17 is a rotor 15 and Impeller
16 common axes are shown, and the main part of the turbocharger 18 is composed of these 12 to 17 parts.

19 is an exhaust turbine 12 scroll, 20 is an exhaust turbine
An elbow that connects the exhaust gas emitted from 12 to the exhaust pipe on the downstream side, and in order to control the discharge pressure of the compressor 13 by adjusting the amount of effective exhaust gas that passes through the turbine rotor 15, one of the turbine scroll 19 A waste gate valve 22 is openably and closably supported by the shaft 1 and an arm (not shown) which is an extension of the shaft 1 in a bypass passage 21 which is open between the portion and the elbow 20.

As shown in FIG. 2 and FIG. 3 in an enlarged manner, the shaft 1 has one end of the link plate 3 in the same manner as in the conventional case.
It is fixed by means such as caulking 4 or welding. However, a hole 23 is opened at the other end of the link plate 3, and the shaft portion 25 of the pin 24 is rotatably inserted into the hole 23.
The E-ring 26 has been used to make a break.

The pin 24 is fixed to one end of a long rod 28 driven by an actuator 27 (FIG. 1) by means of caulking portion 29 or welding. In FIG. 1, 30 is a diaphragm provided inside the actuator 27 and connected to the rod 28, and 31 is a spring that presses the diaphragm 29 to the left (to close the wastegate valve 22). There is. 32 is a control pressure chamber, and a fluid pressure such as air pressure introduced therein causes a waste gate valve through the diaphragm 30.
22 is driven to open / close the bypass passage 21 to adjust the amount of exhaust gas to be bypassed.

In this embodiment, while ordinary steel is used for a relatively large and large amount of material such as the rod 28, which is merely a strength member, a relatively high temperature or sliding is used. The pin 24, the E-ring 26, the link plate 3, etc., which have moving parts, and are small in size and require little material to be used, have heat resistance and oxidation resistance, and are also excellent in wear resistance. To use.

Therefore, even if the rod 28 is made of ordinary steel which is not so high in heat resistance and wear resistance, the pin 24 fixed to it by means such as caulking or welding is made of stainless steel, On the other hand, small parts such as the link plate 3 and the E-ring 26 that are rotatably connected are also made of stainless steel, so that they receive heat from the exhaust turbine 12 and exhaust pipes before and after the exhaust turbine 12 and become high temperature. Even so, high-grade materials are used for the minimum necessary parts, so the rotating parts do not corrode at high temperatures or lock due to rust, and there is also the risk of abnormal wear of holes and pins. Absent.

FIG. 4 shows another embodiment of the present invention, which is third in that the link plate 33 is bent and the rod 28 is provided on the same side as the shaft 1 with respect to the link plate 33. It differs from the case of the figure. However, the operation and effect are generally the same as those in FIGS. 2 and 3. By bending the link plate 33 in this manner, the degree of freedom in design is increased in selecting the relative positional relationship between the actuator 27 and the waste gate valve 22.

[Effect of device]

According to the present invention, there is no need to change the number of parts or their materials as compared with the conventional one, and there is no need for plating or heat treatment.
It is advantageous because it can improve the heat resistance, corrosion resistance and hardness of the necessary parts, improve the durability of the rotary sliding part, and prevent sticking and wear of the rotating part due to rust etc. Since only high-grade materials that are difficult to process are used for only a part, the advantages of easy processing and low cost can be obtained. In addition, the production facility has the advantage that it can be used almost as it is, which has been conventionally used.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an overall structure of a turbocharger including an embodiment of the present invention, FIG. 2 is a front view showing a main part of the embodiment of the present invention, FIG. 3 is a sectional view thereof, and FIG. Is a sectional view showing another embodiment, FIG. 5 is a front view showing a conventional example, and FIG. 6 is a sectional view thereof. 1 ... Shaft, 2 ... Bushing, 3 ... Link plate, 4
... Caulking, 5 ... Pin, 6 ... Caulking, 7 ... Shaft, 8 ... Rod, 9 ... Hole, 10 ... Groove, 11 ... E-ring, 12 ... Exhaust turbine, 13 ... Air supply compressor, 14 ... Center housing, 15 ... turbine rotor, 16 ... compressor impeller, 17 ... common shaft,
18 ... Turbocharger, 19 ... Turbine scroll, 20 ...
Elbow, 21 ... Bypass passage, 22 ... Wastegate valve,
23 ... Hole, 24 ... Pin, 25 ... Shaft, 26 ... E-ring, 27 ... Actuator, 28 ... Rod, 29 ... Caulking, 30 ... Diaphragm, 31 ... Spring, 32 ... Control pressure chamber.

Claims (1)

(57) [Scope of utility model registration request] 1. A pin made of stainless steel is fixed to the tip of a rod made of steel and connected to an actuator, and the stainless steel is provided in a hole provided at one end of a link plate made of stainless steel. A wastegate for a turbocharger, wherein a steel pin is rotatably inserted, and the other end of the stainless steel link plate is fixed to one end of a shaft that drives a wastegate valve. Valve drive mechanism.