JPS633377Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a lubrication structure for a wastegate valve device of an internal combustion engine with an exhaust turbo supercharger, in which the exhaust gas bypass valve is operated by a diaphragm device.

Generally, as shown in FIG. 1, in an internal combustion engine 4 equipped with an exhaust turbo supercharger 3 in which a turbine 1 and a compressor 2 are disposed coaxially, the turbine 1 is driven by exhaust gas G from an exhaust pipe 5. The compressor 2 is rotated, and air A pressurized by the compressor 2 is introduced into each cylinder of the internal combustion engine from the intake pipe 6. However, if the boost pressure exceeds a certain pressure, the durability of the engine itself will deteriorate. I have a problem with the above, so
A bypass passage 8 having a bypass valve 7 is provided in the middle of the pipe line from the exhaust pipe 5 to the turbine 1, and by opening this bypass valve 7 using a diaphragm device 10, a part of the exhaust gas G is bypassed, and the exhaust gas G is bypassed. By reducing the amount of work of the turbine 1 and maintaining the boost pressure by the compressor 2 at an appropriate level, the bypass valve 7 is opened using the diaphragm device 10 in the medium and low load range where the engine load is below the set value. The engine is equipped with a wastegate valve device that cancels the engine's function and leaves the engine in a non-supercharging state.

In this case, the boost pressure from the intake pipe 6 and the air pressure from the air tank 25 are received by the diaphragm 11 in the diaphragm device 10 via the intake introduction pipe 9 by the three-way solenoid valve 26 via the load switch 27, and this pressure is When the mounting load of the spring 12 is exceeded, the bypass valve 7 attached to the diaphragm 11 opens the bypass passage 8.

FIG. 2 is a sectional view of a main part of the conventional waste gate valve device shown in FIG. 1. The diaphragm device 10 has a diaphragm 1 inside the casing 13.
1 as a boundary, the diaphragm 11 has an atmospheric hole 14 communicating with the atmosphere, and the bypass valve 7 is attached via a plate 17 and a locking piece 18.
The diaphragm chamber 16 includes a spring chamber 15 containing a spring 12 that presses the spring 12, and a diaphragm chamber 16 through which the pressure acting on the diaphragm 11 against the spring 12 is guided through the intake pipe 9. Note that 19 is a bearing bush.

In the conventional wastegate valve device configured as described above, the diaphragm 11 moves so that the pressure introduced into the diaphragm chamber 16 and the pressing force of the spring 12 are balanced, and the bypass valve 7
Open and close.

However, in the conventional wastegate device configured as described above, when a surging phenomenon occurs in the spring 12 due to the vibration of the internal combustion engine 4 and the opening/closing of the bypass valve 7, contact between the lines of the spring 12, especially the winding of the spring 12, occurs. Due to the contact between the wires at the beginning and end of the winding, the spring 12 is worn out, weakened, and damaged, and the diaphragm 11 is damaged by abrasion powder, causing the diaphragm device 10 to become damaged.
The disadvantage is that the reliability of the system is compromised.

This invention was devised to eliminate the drawbacks of the conventional waste gate valve device, and its purpose is to lubricate the spring chamber, which is the movable part of the diaphragm device of the waste gate valve device. The purpose of this invention is to prevent wear of the spring, thereby preventing damage to the spring itself and damage caused by abrasion powder of the diaphragm, thereby improving the reliability of the diaphragm device.

The lubrication structure of the wastegate valve device of this invention that achieves the above object is a wastegate valve device that uses a diaphragm device to open and close an exhaust bypass passage that bypasses an exhaust turbine of an internal combustion engine equipped with an exhaust turbo supercharger. The spring chamber is provided with an inlet pipe for introducing the blow-by gas and an exhaust pipe for discharging the blow-by gas, so that the blow-by gas is caused to flow through the spring chamber.

Embodiments of this invention will be described below with reference to the drawings, and parts and portions that are the same as those of the conventional example will be given the same reference numerals as those of the conventional example.

FIG. 3 is an enlarged sectional view of a main part of an embodiment of the lubrication structure of the wastegate valve device of this invention.

In this invention, the exhaust gas G flowing through the exhaust pipe 5 is
In this waste gate valve device, the gas is caused to flow into the exhaust bypass passage 8 by opening the bypass valve 7 driven by the diaphragm device 10. A blow-by gas introduction pipe 21 and a blow-by gas discharge pipe 22 are installed in a spring chamber 15 having a spring 12 mounted so as to press the diaphragm 11.
will be established. Then, the air hole that conventionally communicated the spring chamber 15 with the atmosphere is closed.

The blow-by gas introduction pipe 21 and the blow-by gas discharge pipe 22 are connected to predetermined locations of the internal combustion engine 4 equipped with the exhaust turbo supercharger 3 through pipes 23 and 24 such as rubber hoses, as shown in FIG. That is, the blow-by gas inlet pipe 21 is connected to the blow-by gas outlet (cylinder head cover 41 in this embodiment) of the internal combustion engine 4 through a pipe 23, and the blow-by gas discharge pipe 22 is connected to the compressor of the internal combustion engine 4 through a pipe 24. Connect to the intake path upstream from 2.

Since the waste gate valve device of this invention is constructed as described above, the blow-by gas B always passes through the spring chamber 15 of the diaphragm device 10 during engine operation. Since this blow-by gas B contains engine lubricating oil in the form of mist (oil mist), the waste gate valve device of this invention is filled with blow-by gas B containing this oil mist during engine operation. In the spring chamber 15, even if contact occurs between the lines of the spring 12, the oil mist causes the spring 1 to
Since the spring 12 is lubricated, direct contact is prevented, and therefore wear of the spring 12 is prevented.

Furthermore, since the pressure of the blow-by gas B is slightly higher than atmospheric pressure (on the order of mmAq), even if this invention is applied to a conventional waste gate valve device, the operating point of the diaphragm device (bypass valve (opening/closing timing) has almost no effect.

As explained above, this invention is a waste gate valve device that opens and closes an exhaust bypass passage that bypasses an exhaust turbine of an internal combustion engine with an exhaust turbo supercharger by using a diaphragm device, and the invention is based on a waste gate valve device that uses a diaphragm device to open and close an exhaust bypass passage that bypasses an exhaust turbine of an internal combustion engine equipped with an exhaust turbo supercharger. By allowing the blow-by gas to flow, the spring inside the spring chamber is lubricated by the oil mist in the blow-by gas, which prevents the spring from wearing even if the springs come into contact with each other, increasing the durability of the spring. Since damage to the diaphragm due to abrasion powder of the spring is also prevented, the reliability of the waste gate valve device is improved.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the configuration of an internal combustion engine with an exhaust turbo supercharger equipped with a conventional waste gate valve device.
FIG. 2 is an enlarged cross-sectional view of the main parts showing the specific structure of the waste gate valve device of FIG. 1, and FIG. 3 is an enlarged cross-sectional view of the main parts showing one embodiment of the lubrication structure of the waste gate valve device of this invention. FIG. 4 is an explanatory diagram showing the structure of the waste gate valve device of this invention installed in an internal combustion engine with an exhaust turbo supercharger. 1... Turbine, 3... Exhaust turbo supercharger, 4
... Internal combustion engine, 5 ... Exhaust pipe, 8 ... Exhaust bypass path, 9 ... Intake introduction pipe, 10 ... Diaphragm device, 11 ... Diaphragm, 12 ... Spring, 15 ... Spring chamber, 21 ... Blowby gas introduction pipe, 22... Blowby gas discharge pipe, 2
3,24...Piping.

Claims (1)

[Scope of utility model registration request] A wastegate that opens and closes the exhaust bypass passage that bypasses the exhaust turbine of an internal combustion engine with an exhaust turbo supercharger using a diaphragm device that is composed of a spring chamber in which a spring is arranged and a diaphragm chamber on which pressure acts, with the diaphragm as the boundary. A lubrication structure for a wastegate valve device, characterized in that the spring chamber of the diaphragm device is provided with an introduction pipe for introducing blow-by gas, and the blow-by gas is caused to flow through the spring chamber.