CN115717557A - Crankcase ventilation system and method - Google Patents

Abstract

The invention discloses a crankcase ventilation system and a crankcase ventilation method. The system comprises a crankcase, an oil-gas separator, a first ventilation channel, a second ventilation channel, an air inlet pipe, an air inlet manifold, a double check valve, a check valve and a controller: the double one-way valve is arranged in an air path between the first ventilation channel and the air inlet manifold; the controller is respectively electrically connected with the double check valve and the check valve and is used for controlling the double check valve to be in a first communication state and controlling the check valve to be closed when the engine is in a first load state, so that gas in the crankcase enters the intake manifold through the first ventilation channel and the double check valve; the air supply device is also used for controlling the double check valves to be in a second communication state and controlling the check valves to be communicated when the engine is in a second load state and the air inlet manifold is in a positive pressure state, so that gas in the crankcase enters the air inlet pipe through the second ventilation channel and the check valves and enters the first ventilation channel through the double check valves, integration of air supply and the first ventilation channel can be achieved, the structure is simple, and cost is saved.

Description

Crankcase ventilation system and method

Technical Field

The invention relates to the technical field of automobile engines, in particular to a crankcase ventilation system and a crankcase ventilation method.

Background

With the continuous implementation of passenger vehicle-related regulations in various places, the engine needs to be equipped with a Positive Crankcase Ventilation (PCV) system that satisfies the relevant regulations.

At present, a hybrid supercharged engine has a low-temperature use working condition due to intermittent use, air is required to be supplied to the engine so as to eliminate accumulated water in a crankcase, and therefore the normal work of the engine is ensured.

In addition, at present, a hybrid engine crankshaft ventilation system scheme adopted by each Original Equipment Manufacturer (OEM) is a continuous diagnostic circuit air supplement pipe scheme, which needs to integrate plug connectors in each ventilation pipeline of the PCV system, the plug connectors collect corresponding electrical signals and transmit the electrical signals to an Electronic Control Unit (ECU) of an automobile, and the crankcase ventilation system is confirmed to be complete according to the electrical signals of the ECU so as to meet the requirements of relevant regulations, and the hybrid engine crankshaft ventilation system scheme is complex in structure and high in cost.

Disclosure of Invention

The embodiment of the invention provides a crankcase ventilation system and a crankcase ventilation method.

In a first aspect, an embodiment of the present invention provides a crankcase ventilation system, including a crankcase, an oil-gas separator, a first ventilation channel, a second ventilation channel, an intake pipe, an intake manifold, a double check valve, a check valve, and a controller:

the oil-gas separator is respectively communicated with the first ventilation channel and the second ventilation channel;

the double check valve is arranged in an air path between the first ventilation channel and the air inlet manifold;

the one-way valve is arranged in a gas path between the second ventilation channel and the gas inlet pipe;

the controller is respectively electrically connected with the double one-way valve and the one-way valve and is used for controlling the double one-way valve to be in a first communication state and controlling the one-way valve to be closed when the engine is in a first load state, so that gas in a crankcase enters the intake manifold through the first ventilation channel and the double one-way valve; the double check valve is controlled to be in a second communication state and the check valve is controlled to be communicated when the engine is in a second load state and the intake manifold is in a positive pressure state, so that gas in the crankcase enters the intake pipe through the second ventilation passage and the check valve and enters the first ventilation passage through the double check valve; wherein the load amount of the first load state is smaller than the load amount of the second load state.

Optionally, the crankcase ventilation system further comprises an air filter;

the air filter is communicated with the air inlet pipe.

Optionally, the crankcase ventilation system further comprises a heating passage;

the heating channel is communicated with an air outlet of the air inlet manifold.

Optionally, the heating channel is integrally disposed in the first ventilation channel.

Optionally, the double one-way valve is integrally disposed in the first ventilation channel.

Optionally, the check valve is integrally disposed in the intake pipe.

Optionally, the crankcase ventilation system further comprises a pressure control valve;

the pressure control valve is integrated on the oil-gas separator, and gas in the crankcase enters the first ventilation channel or the second ventilation channel through the pressure control valve.

Optionally, the crankcase ventilation system further comprises a pressure sensor;

the pressure sensor is arranged on the intake manifold and is configured to detect a pressure value in the intake manifold;

the controller is electrically connected with the pressure sensor and used for monitoring the working state of the crankcase ventilation system according to the pressure value.

Optionally, the crankcase ventilation system further comprises a supercharger and a throttle body;

the supercharger and the throttle body are provided on a connection passage between the intake pipe and the intake manifold.

In a second aspect, an embodiment of the present invention further provides a crankcase ventilation method applied to the crankcase ventilation system described in any one of the first aspects, the method including:

when the engine is in a first load state, outputting a first control signal to control the double one-way valve to be in a first communication state and control the one-way valve to be closed, so that gas in a crankcase enters the intake manifold through the first ventilation channel and the double one-way valve;

when the engine is in a second load state and the intake manifold is in a positive pressure state, outputting a second control signal to control the double one-way valve to be in a second communication state and control the one-way valve to be conducted, so that gas in the crankcase enters the intake pipe through the second ventilation passage and the one-way valve, and the first ventilation passage is conducted through the double one-way valve; wherein the load amount of the first load state is smaller than the load amount of the second load state.

According to the crankcase ventilation system provided by the embodiment of the invention, the double one-way valves are arranged in the air path between the first ventilation channel and the intake manifold, and the one-way valves are arranged in the air path between the second ventilation channel and the intake pipe, so that when the engine is in a first load state, the controller can control the double one-way valves to be in a first communication state and control the one-way valves to be turned off, and therefore, the gas in the crankcase can enter the intake manifold through the first ventilation channel and can be prevented from entering the intake manifold; in addition, the controller is also used for controlling the double check valves to be in a second communication state and controlling the check valves to be conducted when the engine is in a second load state and the air inlet manifold is in a positive pressure state, so that gas in the crankcase enters the oil-gas separator and then enters the air inlet pipe through the second ventilation channel and the check valves, air can enter the air inlet pipe, the gas in the crankcase and the air are mixed and then enter the air inlet manifold and enter the engine through the first ventilation channel through the double check valves to achieve the air supplementing function, and integration of air supplementation and the first ventilation channel can be achieved.

Drawings

FIG. 1 is a schematic structural view of a crankcase ventilation system according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of a crankcase ventilation method according to an embodiment of the invention.

Detailed Description

The present invention will be described in further detail with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Fig. 1 is a schematic structural view of a crankcase ventilation system according to an embodiment of the present invention. As shown in fig. 1, the crankcase ventilation system includes a crankcase 100, an air-oil separator 200, a first ventilation passage 300, a second ventilation passage 400, an intake pipe 500, an intake manifold 600, a double check valve 700, a check valve 800, and a controller: the oil-gas separator 200 is respectively communicated with the first ventilation channel 300 and the second ventilation channel 400; the double check valve 700 is disposed in the air path between the first ventilation channel 300 and the intake manifold 600; the check valve 800 is disposed in the air path between the second ventilation passage 400 and the air inlet pipe 500; the controller is electrically connected with the double check valve 700 and the check valve 800 respectively, and is used for controlling the double check valve 700 to be in a first communication state and controlling the check valve 800 to be closed when the engine is in a first load state, so that the gas in the crankcase 100 enters the intake manifold 600 through the first ventilation channel 300 and the double check valve 700; and is also used for controlling the double check valve 700 to be in the second communication state and controlling the check valve 800 to be conducted when the engine is in the second load state and the intake manifold 600 is in the positive pressure state, so that the gas in the crankcase 100 enters the intake pipe 500 through the second ventilation passage 400 and the check valve 800 and enters the first ventilation passage 300 through the double check valve 700; wherein the load amount of the first load state is smaller than the load amount of the second load state.

Illustratively, the controller may be an ECU, and the controller is electrically connected to the double check valve 700 and the check valve 800, respectively. For example, the first load state may be a condition where the engine load is below 25%, i.e. the engine is in a light load state; the second load state may be a condition where the engine load is more than 85% and less than 100%, i.e., the engine is in a heavy load state, that is, the load amount in the first load state is less than the load amount in the second load state. For example, the negative pressure state of intake manifold 600 may be when engine speed is low and intake manifold 600 is at a low pressure, and the positive pressure state of intake manifold 600 may be when engine speed is high and intake manifold 500 is at a pressure greater than normal atmospheric pressure.

It should be noted that the double check valve 700 in the first communication state may allow the gas in the crankcase 100 to enter the intake manifold 600 through the first ventilation channel 300, and the double check valve 700 in the second communication state may allow the gas to enter the first ventilation channel 300 through the intake manifold 600, so as to enter the engine to achieve the gas supplementing function. Further, the first ventilation passage 300 is integrated in the cylinder head assembly to be non-detachable, and the oil separator 200 is fixed to the cover by bolts to form a part of the engine, so that the first ventilation passage 300 satisfies the relevant legislative requirements.

Specifically, with continued reference to fig. 1, when the engine is in the first load state, the controller controls the two-way valve 700 to be in the first communication state and controls the one-way valve 800 to be closed, so that the gas in the crankcase 100 enters the gas-oil separator 200 and then enters the intake manifold 600 through the first ventilation channel 300 and the two-way valve 700, and it can be understood that the air can be prevented from entering the intake manifold 600 because the one-way valve 800 is closed. Further, when the engine is in the second load state and the intake manifold 600 is in the positive pressure state, the controller controls the double check valve 700 to be in the second communication state and controls the check valve 800 to be communicated, so that the gas in the crankcase 100 enters the oil-gas separator 200 and then enters the intake pipe 500 through the second ventilation channel 400 and the check valve 800, it can be understood that the air can enter the intake pipe 500, the gas in the crankcase 100 and the air are mixed and then enter the intake manifold 600 and enter the engine through the first ventilation channel 300 through the double check valve 700, and the controller can control the double check valve 700 to be in the second communication state when the engine is in the large load state and the intake manifold is in the positive pressure state, that is, the function of air supplement of the crankcase ventilation system through the double check valve can be realized.

According to the crankcase ventilation system provided by the embodiment of the invention, the double one-way valves are arranged in the air path between the first ventilation channel and the intake manifold, and the one-way valves are arranged in the air path between the second ventilation channel and the intake pipe, so that when the engine is in a first load state, the controller can control the double one-way valves to be in a first communication state and control the one-way valves to be turned off, and therefore, the gas in the crankcase can enter the intake manifold through the first ventilation channel and can be prevented from entering the intake manifold; in addition, the controller is also used for controlling the double check valves to be in a second communication state and controlling the check valves to be communicated when the engine is in a second load state and the air inlet manifold is in a positive pressure state, so that gas in the crankcase enters the oil-gas separator and then enters the air inlet pipe through the second ventilation channel and the check valves, air can enter the air inlet pipe, the gas in the crankcase and the air are mixed and then enter the air inlet manifold and enter the engine through the first ventilation channel through the double check valves to achieve the air supplementing function, namely, the integration of air supplementing and the first ventilation channel can be achieved, the structure is simple, and the cost is saved.

Optionally, with continued reference to FIG. 1, the crankcase ventilation system further includes an air cleaner 900; the air cleaner 900 communicates with the intake duct 500.

Specifically, the external air may enter the intake duct 500 after passing through the air cleaner 900. When the engine is in the second load state and the intake manifold 600 is in the positive pressure state, the controller may control the double check valve 700 to be in the second communication state and control the check valve 800 to be turned on, and the gas in the crankcase 100 and the air passing through the air cleaner 900 are mixed and then enter the intake manifold 600, and enter the first ventilation channel 300 through the double check valve 700 and enter the engine, so as to realize the gas supplementing function.

Optionally, the crankcase ventilation system further comprises a heating channel; the heating channel is communicated with the air outlet of the air inlet manifold.

Specifically, referring to fig. 1, the external air may enter the intake manifold 600 through the air filter 900, and then the air is heated through the heating channel communicated with the air outlet of the intake manifold 600, and the heated air enters the engine to absorb the water vapor in the engine, thereby avoiding water accumulation in the engine.

Optionally, the heating channel is integrally disposed in the first ventilation channel.

Specifically, referring to fig. 1, the external air may enter the intake manifold 600 through the air filter 900, and it should be noted that, under the condition of relatively low external temperature, the cold air may heat the air through the heating channel communicated with the air outlet of the intake manifold 600, and the heated air may absorb the water vapor in the engine after entering the engine through the first ventilation channel 300, so as to avoid engine water accumulation.

Optionally, with continued reference to fig. 1, a double check valve 700 is integrally disposed in the first vent passage 300.

For example, the double check valve 700 and the first ventilation passage may be fastened by a bolt structure.

Specifically, with continued reference to fig. 1, when the engine is in the first load state, the controller controls the double check valve 700 to be in the first communication state, so that the gas in the crankcase 100 enters the gas-oil separator 200 and then enters the intake manifold 600 through the first ventilation channel 300 and the double check valve 700. When the engine is in the second load state and the intake manifold 600 is in the positive pressure state, the controller controls the double check valve 700 to be in the second communication state, and air can enter the intake manifold 600 and enter the engine from the first ventilation channel 300 through the double check valve 700, so that the air supplementing function is realized.

Optionally, with continued reference to fig. 1, a check valve 800 is integrally provided in the intake pipe 500.

For example, the check valve 800 and the air inlet pipe 500 may be integrated by means of thermoplastic molding, so as to fasten the check valve 800 and the air inlet pipe 500.

Specifically, with continued reference to FIG. 1, when the engine is in a first load state, the controller controls the check valve 800 to close to prevent air from entering the intake manifold 600. When the engine is in the second load state, the controller controls the one-way valve 800 to be conducted, so that the gas in the crankcase 100 enters the oil-gas separator 200 and then enters the air inlet pipe 500 through the second ventilation channel 400 and the one-way valve 800.

Optionally, the crankcase ventilation system further comprises a pressure control valve; the pressure control valve is integrated on the oil-gas separator, and gas in the crankcase enters the first ventilation channel or the second ventilation channel through the pressure control valve.

Specifically, with continued reference to fig. 1, when the engine is in the first load state, the gas in the crankcase 100 may enter the first ventilation channel 300 through the pressure control valve on the gas-oil separator 200, and further, when the engine is in the second load state, the gas in the crankcase 100 may enter the second ventilation channel 400 through the pressure control valve on the gas-oil separator 200, that is, by integrally disposing the pressure control valve on the gas-oil separator 200, the gas in the crankcase 100 may enter the first ventilation channel 300 or the second ventilation channel 400 through the pressure control valve.

Optionally, with continued reference to fig. 1, the crankcase ventilation system further comprises a pressure sensor; a pressure sensor disposed on intake manifold 700 and configured to detect a pressure value within intake manifold 700; the controller is electrically connected with the pressure sensor and used for monitoring the working state of the crankcase ventilation system according to the pressure value.

Illustratively, the second vent channel 400 is a detachable connection pipe, and the legislative requirements of "On-Board Diagnostics (OBD) alarm for detachable vent pipes" are implemented by: after the ventilation pipe is detached, air is sucked into the intake manifold 600 through the cut-off part by negative pressure in the intake manifold 600, then the negative pressure value in the intake manifold 600 is reduced, and after the negative pressure value exceeds the theoretical value of 20kPa, the alarm of the intake pressure of the controller is triggered, so that the working state of the crankcase ventilation system is monitored, and therefore the second ventilation channel 400 meets the requirements of relevant regulations. In addition, the pressure detection can replace the traditional continuous diagnosis circuit detection, namely, self diagnosis is realized, the detection cost is low, and the reliability of the detection method is high.

Optionally, with continued reference to fig. 1, the crankcase ventilation system further comprises a supercharger 1000 and a throttle body 1100; supercharger 1000 and throttle body 1100 are provided on a connection passage between intake pipe 500 and intake manifold 600.

Specifically, the external air enters the intake duct 500 after passing through the air cleaner 900, then enters the intake manifold 600 through the supercharger 1000 and the throttle body 1100, and then enters the engine through the first ventilation channel 300 by the double check valve 700, thereby achieving the air supplement function.

The crankcase ventilation system provided by the embodiment of the invention comprises a crankcase, an oil-gas separator, a first ventilation channel, a second ventilation channel, an air inlet pipe, an air inlet manifold, a double one-way valve, a one-way valve and a controller. The double one-way valve is arranged in the air path between the first ventilation channel and the air inlet manifold, and the one-way valve is arranged in the air path between the second ventilation channel and the air inlet pipe, so that when the engine is in a first load state, the air in the crankcase can enter the air inlet manifold through the first ventilation channel and can be prevented from entering the air inlet manifold; when the engine is in a second load state and the air inlet manifold is in a positive pressure state, the gas in the crankcase can enter the oil-gas separator and then enter the air inlet pipe through the second ventilation channel and the one-way valve, the air can enter the air inlet pipe, the gas in the crankcase and the air are mixed and then enter the air inlet manifold and enter the engine through the first ventilation channel through the double one-way valve to realize the air supplementing function, and the integration of air supplementing and the first ventilation channel can be realized. In addition, can realize heating the gas in the air intake manifold through setting up heating channel, the gas after the heating gets into the engine through first ventilation channel, can absorb the steam in the engine, avoids engine ponding.

Based on the same inventive concept, an embodiment of the present invention further provides a crankcase ventilation method, and fig. 2 is a schematic flow chart of the crankcase ventilation method provided by the embodiment of the present invention. As shown in fig. 2, a crankcase ventilation method provided by an embodiment of the invention may include:

s101, when the engine is in a first load state, outputting a first control signal to control the double check valve to be in a first communication state and control the check valve to be closed, so that gas in the crankcase enters the intake manifold through the first ventilation channel and the double check valve.

For example, the first load state may be when the engine is in a light load condition. The first control signal may be a signal that the controller outputs for controlling the double check valve to be in the first communication state and controlling the check valve to be closed.

Specifically, referring to fig. 1, when the engine is in the first load state, the controller controls the double check valve 700 to be in the first communication state and controls the check valve 800 to be closed, so that the gas in the crankcase 100 enters the gas-oil separator 200 and then enters the intake manifold 600 through the first ventilation channel 300 and the double check valve 700, and it can be understood that the air can be prevented from entering the intake manifold 600 because the check valve 800 is closed.

S102, when the engine is in a second load state and the intake manifold is in a positive pressure state, outputting a second control signal to control the double check valves to be in a second communication state and control the conduction of the check valves, so that gas in the crankcase enters the intake pipe through the second ventilation channel and the check valves, and a first ventilation channel is formed through the double check valves; wherein the load amount of the first load state is smaller than the load amount of the second load state.

As an example, the second load condition may be when the engine is under a heavy load condition. The second control signal may be a signal output by the controller for controlling the double check valve to be in the second communication state and controlling the check valve to be conducted.

Specifically, referring to fig. 1, when the engine is in the second load state and the intake manifold 600 is in the positive pressure state, the controller controls the two-way valve 700 to be in the second communication state and controls the one-way valve 800 to be in the conduction state, so that the gas in the crankcase 100 enters the oil-gas separator 200 and then enters the intake pipe 500 through the second ventilation channel 400 and the one-way valve 800, it can be understood that the gas can enter the intake pipe 500, the gas in the crankcase 100 and the air are mixed and then enter the intake manifold 600 and enter the engine through the first ventilation channel 300 through the two-way valve 700, and when the engine is in the large load state and the intake manifold is in the positive pressure state, the controller can control the two-way valve 700 to be in the second communication state, that is, the function of supplying air to the crankcase ventilation system through the two-way valve can be realized.

According to the crankcase ventilation method provided by the embodiment of the invention, when the engine is in a first load state, gas in the crankcase enters the intake manifold through the first ventilation channel and can be prevented from entering the intake manifold; when the engine is in a second load state and the air inlet manifold is in a positive pressure state, gas in the crankcase enters the oil-gas separator and then enters the air inlet pipe through the second ventilation channel and the one-way valve, air can enter the air inlet pipe, the gas in the crankcase and the air are mixed and then enter the air inlet manifold and enter the engine through the first ventilation channel through the double one-way valve to achieve the air supplementing function, and therefore integration of air supplementing and the first ventilation channel can be achieved.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (10)

1. The crankcase ventilation system is characterized by comprising a crankcase, an oil-gas separator, a first ventilation channel, a second ventilation channel, an air inlet pipe, an air inlet manifold, a double check valve, a check valve and a controller:

the oil-gas separator is respectively communicated with the first ventilation channel and the second ventilation channel;

the double one-way valve is arranged in an air path between the first ventilation channel and the air inlet manifold;

the one-way valve is arranged in a gas path between the second ventilation channel and the gas inlet pipe;

the controller is respectively electrically connected with the double check valve and the check valve and is used for controlling the double check valve to be in a first communication state and controlling the check valve to be closed when the engine is in a first load state, so that gas in a crankcase enters the intake manifold through the first ventilation channel and the double check valve; the double check valve is controlled to be in a second communication state and the check valve is controlled to be communicated when the engine is in a second load state and the intake manifold is in a positive pressure state, so that gas in the crankcase enters the intake pipe through the second ventilation passage and the check valve and enters the first ventilation passage through the double check valve; wherein the load amount of the first load state is smaller than the load amount of the second load state.

2. The crankcase ventilation system of claim 1, further comprising an air filter;

the air filter is communicated with the air inlet pipe.

3. The crankcase ventilation system of claim 1, further comprising a heating passage;

the heating channel is communicated with the air outlet of the air inlet manifold.

4. The crankcase ventilation system of claim 3, wherein the heating passage is integrally disposed within the first ventilation passage.

5. The crankcase ventilation system of claim 1, wherein the double check valve is integrally disposed in the first ventilation passage.

6. The crankcase ventilation system of claim 1, wherein the check valve is integrally disposed in the intake tube.

7. The crankcase ventilation system of claim 1, further comprising a pressure control valve;

the pressure control valve is arranged on the oil-gas separator in an integrated mode, and gas in the crankcase enters the first ventilation channel or the second ventilation channel through the pressure control valve.

8. The crankcase ventilation system of claim 1, further comprising a pressure sensor;

the pressure sensor is arranged on the intake manifold and is configured to detect a pressure value in the intake manifold;

the controller is electrically connected with the pressure sensor and used for monitoring the working state of the crankcase ventilation system according to the pressure value.

9. The crankcase ventilation system of claim 1, further comprising a supercharger and a throttle body;

the supercharger and the throttle body are provided on a connection passage between the intake pipe and the intake manifold.

10. A crankcase ventilation method applied to the crankcase ventilation system according to any one of claims 1-9, comprising:

when the engine is in a first load state, outputting a first control signal to control the double one-way valve to be in a first communication state and control the one-way valve to be closed, so that gas in a crankcase enters the intake manifold through the first ventilation channel and the double one-way valve;

when the engine is in a second load state and the intake manifold is in a positive pressure state, outputting a second control signal to control the double one-way valve to be in a second communication state and control the one-way valve to be conducted, so that gas in the crankcase enters the intake pipe through the second ventilation passage and the one-way valve, and the first ventilation passage is conducted through the double one-way valve; wherein the load amount of the first load state is smaller than the load amount of the second load state.

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