Purge injector assembly for vehicle

Abstract

A purge injector assembly (10) for a vehicle includes a first fluid passage (111), a second fluid passage (115), and a flow shaping unit (20); a flow shaping unit (20) is disposed within the first fluid passage (111) between the engine airflow port (122) and the air passage airflow port (112), the flow shaping unit (20) is configured to increase a flow rate of air flowing in a direction from the engine airflow port (122) to the air passage airflow port (113) when a first pressure level (P1) is applied to the engine airflow port (122), thereby subjecting the second fluid passage (115) to a second pressure level (P2) lower than the first pressure level (P1). The purging ejector assembly can control the emptying process of a carbon canister of an automobile fuel system under various engine working conditions. With this type of purge injector assembly, fuel vapors can be effectively purged from the canister.

Description

Technical Field

[0001] This disclosure relates to a purge injector assembly for a vehicle, wherein the purge injector assembly is typically implemented in a vehicle fuel system or a vehicle engine system. This disclosure also relates to an evaporative fuel purging system including a purge injector assembly, a method for injecting evaporative fuel, and a vehicle including a purge injector assembly.

[0002] Although this technical solution is described in relation to a passenger car, it is not limited to that particular vehicle, but can also be installed in other types of vehicles, such as minivans, recreational vehicles, off-road vehicles, and heavy vehicles (such as trucks, buses, and construction equipment). Background Technology

[0003] Vehicle engines, especially gasoline-powered internal combustion engines, but also other types of engines, are typically connected to a fuel system configured to supply fuel to the engine or engine system. This fuel system includes a fuel tank and other components such as fuel pumps and fuel lines. Most of these systems also include a so-called fuel vapor purging (EVAP) system to prevent fuel vapor from escaping from the fuel tank into the atmosphere. In this context, it should be noted that fuel systems are generally not permitted to leak more fuel vapor into the atmosphere than legally allowed.

[0004] EVAP systems are typically configured to capture fuel vapor from the fuel tank and temporarily store it in a charcoal canister. When the vehicle's engine is running under certain conditions, the fuel vapor is purged from the charcoal canister and burned within the engine. The charcoal canister needs to purge hydrocarbons to ensure emissions remain at satisfactory levels. To determine when the charcoal canister should be purged, EVAP systems may also include a purge valve or other control mechanism adapted to control the amount of fuel vapor intended to be purged from the activated charcoal canister. In many vehicles, such as modern cars, the purge valve is controlled by the engine computer. When the engine is off, the purge valve is closed. As the engine runs and fully warms up, the engine computer gradually opens the purge valve to allow a certain amount of fuel vapor to be transferred from the activated charcoal canister to the engine.

[0005] Some systems may include purge injector assemblies to further improve the process of efficiently venting the charcoal canister, which can operate during both low-pressure and high-pressure conditions of the vehicle engine. Purge injector systems can be designed in a variety of different ways, including purge injectors and one or more valves for controlling the flow of fuel vapor between the components that make up the EVAP system and the engine system.

[0006] However, current regulations in the automotive market have led to a growing demand for improvements to the process of purging fuel vapor from the charcoal canister into the engine in existing vehicles. Furthermore, fuel vapor regulations are becoming increasingly stringent due to growing environmental concerns. These regulations must be balanced with the need for engine systems that provide high-performance vehicles. These issues and demands are particularly evident for engine systems with compressors, such as turbochargers.

[0007] There are several different solutions for arranging the purge injector in the fluid passage between the charcoal canister and the engine system, and these solutions depend in part on the design of the engine system and the EVAP system.

[0008] It would be advantageous if a purge injector or purge injector assembly for the engine could be installed in known or commercially available vehicles without requiring significant modifications to the fuel system or EVAP system, while effectively purging the charcoal canister during engine operation. Furthermore, a purge injector solution that is highly efficient during both low-pressure and boosted engine conditions is desired, thereby minimizing the energy required to remove fuel vapors from the charcoal canister. Summary of the Invention

[0009] The object of this invention is to provide an improved purge injector assembly for a vehicle, a fuel vapor purging system, and a method for injecting vaporized fuel, wherein the aforementioned problems are avoided. In particular, the object of this disclosure is to provide a purge injector assembly for an engine that can control the purging process of the vehicle's fuel system's charcoal canister during various engine operating conditions, such as during idling and during boosting in the vehicle's driving cycle. This objective is achieved at least in part by the features defined in the independent claims. The dependent claims cover further improvements to the purge injector assembly.

[0010] By providing a purge injector assembly including the construction described above, improvements to the existing operation of fuel systems become feasible. In particular, the present invention provides a purge injector assembly capable of controlling the purge airflow both when the engine is operating under low-pressure and boost conditions. In this way, the purge injector assembly can control the process of emptying the charcoal canister of the vehicle's fuel system during various engine operating conditions, namely during idling in the driving cycle and during boosting in the driving cycle. This may be particularly important for vehicles with small engine displacements and so-called stop / start functions, as well as vehicles with hybrid engines. The aforementioned advantages are also believed to further contribute to better compliance with current regulations regarding exhaust and fuel emissions. Therefore, exemplary embodiments of this disclosure can improve the overall performance of the purge injector assembly.

[0011] This disclosure relates to a purge injector assembly for a vehicle, comprising a first fluid passage having an engine airflow port and an air passage airflow port in fluid communication with each other; and a second fluid passage connected to the first fluid passage, the second fluid passage having a purge airflow port and a nozzle opening disposed outside the first fluid passage, wherein the purge airflow port and the air passage airflow port are in fluid communication with each other, wherein the purge airflow port is connectable to a charcoal canister cleaning passage, such that evaporated fuel can flow from the charcoal canister cleaning passage through the purge airflow port to the air passage airflow port in the second fluid passage. The purge injector assembly further includes a flow shaping unit disposed within the first fluid passage between the engine airflow port and the air passage airflow port, wherein the flow shaping unit is configured to increase the flow velocity of air flowing in the direction from the engine airflow port to the air passage airflow port when a first pressure level is applied to the engine airflow port, thereby subjecting the second fluid passage to a second pressure level lower than the first pressure level. The second fluid channel extends into the first fluid channel such that the nozzle opening is arranged within the first fluid channel and faces the airflow port of the air channel, thereby causing the airflow in the first fluid channel to flow around the nozzle opening, and wherein the flow shaping unit is disposed within the first fluid channel and is associated with the nozzle opening.

[0012] The advantage of these features is that this type of purge injector assembly can effectively purge fuel vapor from the charcoal canister. The flow generated around the nozzle opening creates a low secondary pressure level that draws out the fuel vapor, while the energy consumption required for airflow in the primary fluid passage is low. Furthermore, the purge injector assembly can be installed in known or commercially available vehicles without significant modifications to the fuel system or EVAP system, while effectively purging the charcoal canister during engine operation.

[0013] According to one aspect of this disclosure, the airflow in the first fluid channel flows along the inner wall of the first fluid channel around the nozzle opening. In this way, the airflow is effectively distributed in the purge injector assembly for efficient extraction of fuel vapor from the charcoal canister.

[0014] According to another aspect of this disclosure, the nozzle opening and the inner wall of the first fluid passage each have a substantially circular cross-sectional shape, such that the airflow in the first fluid passage, flowing around the nozzle opening in a direction along the first fluid passage from the engine airflow port toward the air passage airflow port, has a substantially annular cross-sectional shape. This annular shape of the airflow further improves the efficiency of the purge injector assembly, thus effectively purging fuel vapor from the charcoal canister.

[0015] According to one aspect of this disclosure, the flow shaping unit includes a converging section configured to increase the velocity of the airflow from the engine airflow port to the air passage airflow port. The converging section is used to establish a low pressure level in the second fluid passage when the air velocity in the first fluid passage increases.

[0016] According to another aspect of this disclosure, the converging portion is formed by the end of the second fluid channel extending into the first fluid channel. In this way, the end of the second fluid channel is used to establish the converging portion, providing a simple and reliable structure.

[0017] According to another aspect of this disclosure, the converging portion is formed by a constriction within the first fluid channel. This provides an alternative way of constructing the converging portion, offering flexibility in shaping the airflow around the nozzle opening.

[0018] According to other aspects of this disclosure, the flow shaping unit includes a diverging section arranged along the flow direction after the converging section, wherein the diverging section is formed by a pipe expansion section within the first fluid channel. The diverging section generates effective flow through the purge injector assembly to purge fuel vapor from the charcoal canister.

[0019] According to one aspect of this disclosure, the purge injector assembly further includes a first valve disposed in the first fluid passage, positioned between the engine airflow port and the flow shaping unit. The first valve is configured to allow fluid to flow from the engine airflow port toward the flow shaping unit through the first valve, while restricting fluid flow from the flow shaping unit toward the engine airflow port through the first valve. A second valve is disposed in the second fluid passage and configured to allow fluid to flow from the purge airflow port toward the air passage airflow port through the second valve, while restricting fluid flow from the air passage airflow port toward the purge airflow port through the second valve. The arrangement and position of the first valve contribute to creating undisturbed flow in the first fluid passage, thereby further improving the performance of the purge injector assembly. This makes it feasible to provide a purge injector assembly that helps to efficiently empty the carbon canister while satisfying exhaust and fuel emission regulations in a more satisfactory manner.

[0020] According to another aspect of this disclosure, the purge injector assembly further includes a third fluid passage and a third valve. The third fluid passage establishes fluid communication between the purge airflow port and the engine airflow port. The third valve is disposed in the third fluid passage, located between the engine airflow port and the purge airflow port. The third valve is configured to allow fluid to flow from the purge airflow port toward the engine airflow port while restricting fluid flow from the engine airflow port toward the purge airflow port, thereby enabling evaporated fuel to flow from the canister cleaning passage to the engine airflow port in the third fluid passage when low pressure is applied to the engine airflow port. The arrangement and position of the first, second, and third valves allow for the determination and control of the purge airflow under both low-pressure and high-pressure conditions. In this way, the canister can be purged under different vehicle operating conditions.

[0021] According to another aspect of this disclosure, the purge injector assembly is a pre-assembled single unit. As a single unit, the purge injector assembly is easy to install in vehicles, and also easy to install in known or commercially available vehicles, without requiring significant modifications to the fuel system or EVAP system, while effectively purging the charcoal canister during engine system operation.

[0022] This disclosure also relates to a fuel tank for storing fuel, a charcoal canister, and a charcoal canister sludge passage extending from the charcoal canister to the engine intake manifold, wherein the charcoal canister is used to absorb evaporated fuel discharged from the fuel tank and is adapted to desorb the evaporated fuel, and the charcoal canister is connected to the fuel tank via a vapor discharge passage. A sludge valve is provided in the charcoal canister sludge passage, the sludge valve being configured to regulate the flow of evaporated fuel in the charcoal canister sludge passage. The system also includes a purge injector assembly as described above.

[0023] This disclosure also relates to a method for injecting vaporized fuel in a vehicle having a purge injector assembly, wherein an airflow is arranged around a nozzle opening in a first fluid passage of the purge injector assembly, wherein the nozzle opening is disposed within the first fluid passage such that the airflow in the first fluid passage flows around the nozzle opening. Further, this disclosure relates to a vehicle including a purge injector assembly.

[0024] The term "connection" generally means that a component is directly or indirectly operationally associated with another component. The term "fuel" as used herein generally refers to gasoline, although fuel can also refer to diesel or any other type of fuel suitable for a vehicle engine.

[0025] Although this disclosure is described in connection with automobiles, it is not limited to this particular vehicle, but can also be applied to other types of vehicles, such as trucks, buses, construction equipment, industrial engineering machinery and wheel loaders. Attached Figure Description

[0026] The present disclosure will now be described in more detail with reference to the accompanying drawings, in which...

[0027] Figure 1 An exemplary embodiment of a fuel system including a purge injector assembly according to the present disclosure is illustrated schematically, wherein the purge injector assembly is part of a fuel vapor purging system.

[0028] Figure 2 schematically shown Figure 1 An exemplary embodiment of a fuel vapor purging system includes a purging injector assembly according to the present disclosure.

[0029] Figure 3 The purge jet assembly according to various exemplary embodiments of the present disclosure is schematically illustrated, wherein the purge jet assembly operates under low-pressure conditions.

[0030] Figure 4 The illustration schematically depicts various exemplary embodiments of a purge jet assembly according to this disclosure, wherein the purge jet assembly operates under pressurized conditions, and

[0031] Figure 5a -b schematically illustrates an exemplary embodiment of a purge jet assembly according to this disclosure. Detailed Implementation

[0032] The various aspects of this technical disclosure will be described below in conjunction with the accompanying drawings, in order to illustrate and not limit the technical disclosure, wherein like reference numerals denote like elements, and variations of the described aspects are not limited to the embodiments specifically shown, but are applicable to other variations of this technical disclosure.

[0033] Figure 1-4 A fuel vapor purging system 102 is schematically shown for installation in a vehicle, such as an automobile. The fuel vapor purging system 102 includes a purge injector assembly 10, and is typically part of the vehicle's fuel system 100. Reference will be made below. Figure 3-4 and Figure 5a -b describes the purge injector assembly 10 in more detail. The vehicle may be, for example, a passenger car. However, the fuel vapor purging system can also be installed and arranged in other types of vehicles.

[0034] exist Figure 1 The vehicle fuel system 100 is schematically shown. The vehicle fuel system can also be designated as fuel system 100. Similarly, the vehicle fuel evaporative purging system 102 can also be referred to as an evaporative purging system, an evaporative emission control system, or simply an EVAP system. Although not strictly necessary, the fuel evaporative purging system 102 is generally part of the fuel system.

[0035] In this exemplary embodiment, a fuel system 100 including an EVAP system is connected to a vehicle engine or engine system 180. Engine system 180 includes the vehicle's engine, and the engine includes one or more cylinders. Furthermore, engine system 180 has an engine intake manifold 104 and an engine exhaust system; the engine intake manifold is also referred to as a manifold or inlet. Typically, engine intake manifold 104 has a throttle valve in fluid communication with it. The engine exhaust system may include an exhaust manifold connecting to an exhaust passage configured to direct exhaust gases to the atmosphere. These components of engine system 180, and their functions and configurations within engine system 180, are well known in the art and will not be described in detail here.

[0036] like Figure 1As shown, the fuel system 100 is connected to an intake unit 185, such as an air filter unit or similar arrangement, adapted to receive fresh air from the outside 114. In this embodiment, the intake unit 185 is located upstream of the engine intake manifold 104. Additionally, such vehicle systems may also include a compressor 188, such as a turbocharger, supercharger, or similar device. The compressor 188 is configured to operate as a booster during engine boosting operation. In this example, the compressor 188 is located or arranged between the engine system 180 and the intake unit 185. Typically, the compressor 188 is arranged between the throttle valve in the engine intake manifold of the engine system 180 and the intake unit 185. The compressor 188 can typically be configured to draw in intake air at atmospheric pressure and boost the air to a higher pressure, typically corresponding to a first pressure level P1, also referred to as the boost pressure.

[0037] By utilizing pressurized intake air, i.e., boosted intake air, the engine system 180 can perform boosted engine operation. The operation of the compressor 188, used to obtain the appropriate boost pressure, can vary depending on the vehicle type and engine type. Furthermore, with regard to the engine system 180, the arrangement, components, and functions of the intake unit 185 and the compressor 188 can vary depending on the vehicle type, engine system type, and fuel system type. Since these components and their functions are well known in the art and can be selected according to the vehicle type and system type, they will not be described in detail here.

[0038] like Figure 1 As shown, fuel system 100 includes a fuel filter pipe 150 connected to fuel tank 140 via fuel filter pipe passage 152. Fuel tank 140, in this example, is adapted to store fuel, such as, for example, gasoline. Fuel tank 140 may include or be connected to a fuel pump system adapted to deliver pressurized fuel to engine system 180, typically to one or more fuel injectors of engine system 180. As described above, Figure 1 and 2 As shown, the fuel system typically includes a fuel vapor purging system 102.

[0039] Figure 2A fuel evaporation purging system 102 according to an exemplary embodiment of the present invention is shown. In this example, the fuel evaporation purging system 102 includes a fuel tank 140 for storing fuel. The EVAP system also includes a charcoal canister 110 for absorbing fuel vapor discharged from the fuel tank and adapted to desorb evaporated fuel. In other words, the charcoal canister 110 is intended to function as a fuel vapor holding device, and the charcoal canister 110 is typically filled with an adsorbent capable of binding a large amount of vaporized hydrocarbons. For example, the charcoal canister 110 may include an adsorbent in the form of activated carbon.

[0040] like Figure 2 As shown, the charcoal canister 110 is connected to the fuel tank 140 via a vapor discharge passage 142. Thus, the charcoal canister 110 can receive fuel vapor from the fuel tank 140 via the vapor discharge passage 142. In some examples, the EVAP system may include a single charcoal canister 110. However, in other examples, the EVAP system may include multiple interconnected charcoal canisters. It should be understood from the above that when fuel is filled into the fuel tank 140, fuel vapor from the fuel tank 140 can be discharged to the charcoal canister 110 via the vapor discharge passage 142 to prevent hydrocarbons from being released into the environment.

[0041] The EVAP system can be connected to the air filter 130 via the air filter ventilation duct 132. The air filter 130 allows the charcoal canister 110 to communicate with the surrounding atmosphere via the air filter ventilation duct 132. It should be readily understood that the charcoal canister 110 can be controlled in various ways depending on the type of vehicle, the type of EVAP system, and the type of charcoal canister 110. As an example, the charcoal canister 110 can be controlled by one or more charcoal canister venting solenoid valves, as is known in the art.

[0042] like Figure 2As shown, the charcoal canister sludge passage 92 extends from the charcoal canister 110 to the engine intake manifold 104. As will be further detailed below, the charcoal canister 110 needs to vent hydrocarbons to ensure emissions remain at satisfactory levels. Therefore, an EVAP system typically includes a sludge valve 90 disposed in the charcoal canister sludge passage 92. The sludge valve 90 is configured to regulate the flow of evaporated fuel in the charcoal canister sludge passage 92. By opening the sludge valve, hydrocarbons contained in the charcoal canister can be delivered to the engine system 180 and subsequently combusted in the engine. The sludge valve 90 can be, for example, software-operated and configured to open and close based on the duty cycle of a solenoid valve connected to the sludge valve 90. For example, the sludge valve 90 can be set to a closed state so that no fuel vapor is purged through the charcoal canister sludge passage 92. Conversely, when the sludge valve 90 is set to an open state, fuel vapor can be purged from the charcoal canister 110. The sludge valve 90 can be a conventional check valve, solenoid valve, etc. Furthermore, as described above, the evaporative fuel purging system 102 includes a purging injector assembly 10 according to various exemplary embodiments described herein.

[0043] like Figure 1 and Figure 2 As shown, the purge injector assembly 10 is located in the charcoal canister cleaning passage 92 between the cleaning valve 90 and the engine intake manifold 104. However, it should be understood that the purge injector assembly 10 can be installed in other locations within the EVAP system and / or the charcoal canister cleaning passage 92. In other words, the charcoal canister cleaning passage 92 is connected to the purge injector assembly 10, which is then connected to the engine system 180 via the engine intake manifold 104.

[0044] The purge ejector assembly 10 includes an ejector pump of the vacuum ejector pump type, which utilizes the known Venturi effect to convert the pressure energy of the motive fluid into velocity energy, thereby creating a low-pressure zone that draws in and entrains the fluid. Details of the purge ejector assembly 10 will be described in more detail below.

[0045] Figure 3 A purge injector assembly 10 according to an exemplary embodiment is schematically shown, wherein the purge injector assembly 10 is subjected to low pressure, such that the purge injector assembly 10 is configured to operate under a so-called low-pressure condition. Under the low-pressure condition, a mixture of air and fuel is drawn into the engine in the engine's naturally aspirated mode, without the use of compressor 188.

[0046] Figure 4 schematically shown Figure 3An exemplary embodiment of the purge injector assembly 10 is described above, wherein the purge injector assembly 10 is pressurized such that the purge injector assembly 10 is configured to operate under a so-called pressurized condition.

[0047] Figure 3 and Figure 4 The EVAP system 102 includes a purge injector assembly 10, which may be provided as a single unit. However, in other examples, the purge injector assembly 10 may also be provided as multiple separate components in the EVAP system, which together constitute the purge injector assembly 10.

[0048] like Figure 5a As shown, the purge injector assembly 10 includes a first fluid passage 111 having an engine airflow port 122 and an air passage airflow port 112 in fluid communication with each other. The first fluid passage 111 is adapted to deliver fluids such as air and fuel vapor, and is capable of delivering fluid in both directions between the engine airflow port 122 and the air passage airflow port 112 unless restricted by a valve as described below. The first fluid passage 111 is arranged to guide pressurized airflow from a compressor 188, the pressurized airflow flowing from the engine airflow port 122 toward the air passage airflow port 112. The first fluid passage 111 may be arranged as a conduit structure in which pressurized air flows. The engine airflow port 122 is arranged in fluid communication with the compressor 188 via an engine intake manifold 104. Thus, a portion of the pressurized air from the compressor 188 is guided through the engine intake manifold 104 and further through the first fluid passage 111. Figure 1 As shown, the airflow port 112 of the air passage is arranged in fluid communication with the intake passage arranged between the intake unit 185 and the compressor 188, so that the airflow through the first fluid passage 111 can flow back to the inlet of the compressor 188. As mentioned above, the intake unit 185 can typically be connected to the compressor 188. However, this example is only one of many possible examples of fluid connection methods between the various components of the system. The airflow in the first fluid passage 111 can be considered as the working fluid in the purge injector assembly 10 having a first pressure level P1, which substantially corresponds to the boost pressure from the compressor 188.

[0049] The second fluid passage 115 connects to the first fluid passage 111. The second fluid passage 115 has a purge airflow port 118 and a nozzle opening 116 disposed outside the first fluid passage 111, wherein the purge airflow port 118 and the air passage airflow port 112 are in fluid communication with each other. The second fluid passage 115 is arranged to guide a fuel vapor flow along a direction from the purge airflow port 118 through the nozzle opening 116 toward the air passage airflow port 112. The second fluid passage 115 can be arranged as a conduit structure in which evaporated fuel flows. The purge airflow port 118 can be connected to the charcoal canister cleaning passage 92, allowing evaporated fuel to flow from the charcoal canister cleaning passage 92 through the purge airflow port 118 to the air passage airflow port 112 within the second fluid passage 115. As described above, Figure 1 As shown, the air passage airflow port 112 is arranged in fluid communication with the intake passage arranged between the intake unit 185 and the compressor 188, so that the fuel vapor flow through the second fluid passage 115 can flow to the inlet of the compressor 188. Therefore, the second fluid passage 115 is arranged for venting or removing evaporated fuel from the charcoal canister 110 via the charcoal canister cleaning passage 92.

[0050] The airflow in the first fluid passage 111 mixes with the fuel vapor flow from the second fluid passage 115 after the nozzle opening 116. Therefore, the mixing of the airflow and the fuel vapor flow will occur within the first fluid passage and will then be delivered through the airflow port 112 of the air passage.

[0051] A flow shaping unit 20 is disposed within the first fluid passage 111, between the engine airflow port 122 and the air passage airflow port 112. The flow shaping unit 20 is configured to increase the velocity of air flowing from the engine airflow port 122 to the air passage airflow port 112 when a first pressure level P1 is applied to the engine airflow port 122 during boost operation of the compressor 188. This causes the second fluid passage 115 to be at a second pressure level P2, which is lower than the first pressure level P1 due to the Venturi effect. This effect is widely known in the art and is commonly used in various injector applications. The system is designed such that, under boost pressure, the second pressure level P2 is lower than the pressure levels in the charcoal canister 110 and the charcoal canister cleaning passage 92, and in this way, fuel vapor is drawn from the charcoal canister 110 through the charcoal canister cleaning passage 92 passing through the second fluid passage 115. The fuel vapor flow in the second fluid passage 111 can be considered as a suction fluid in the purge injector assembly 10 having a second pressure level P2. The first pressure level P1 in the system can vary depending on the pressure output of the compressor 188. The purge injector assembly 10 can be designed based on system parameters to achieve an appropriate second pressure level P2 during pressurization conditions.

[0052] The second fluid channel 115 extends into the first fluid channel 111 such that the nozzle opening 116 is arranged within the first fluid channel 111 and faces the airflow port 112 of the air channel, thereby causing the airflow in the first fluid channel 111 to flow around the nozzle opening 116. Figure 5a As shown, the flow forming unit 20 is disposed within the first fluid channel 111 and is associated with the nozzle opening 116.

[0053] Airflow in the first fluid passage 111 flows along the inner wall 117 of the first fluid passage 111 around the nozzle opening 116. The nozzle opening 116 has a substantially circular cross-sectional shape, and the inner wall 117 of the first fluid passage 111 also has a substantially circular cross-sectional shape. Thus, the airflow in the first fluid passage 111 can be arranged such that it has a substantially annular cross-sectional shape as it flows around the nozzle opening 116 along the first fluid passage 111 in the direction from the engine airflow port 122 toward the air passage airflow port 112. Tests have shown that the airflow with an annular cross-sectional shape around the nozzle opening 116 produces a highly efficient suction effect in the second fluid passage 115. In this way, this specific design of the purge injector assembly 10 can be used to clean the charcoal canister 100 in a highly efficient manner with low energy consumption. Low energy consumption in the purge injector assembly 10 is important to support the reduction of total vehicle emissions.

[0054] The flow shaping unit 20 includes a converging portion 119, which is configured to increase the flow velocity of the airflow from the engine airflow port 122 to the air passage airflow port 112. For example... Figure 5a As shown, the converging portion 119 can be formed by the end 120 of the second fluid channel 115 extending into the first fluid channel 111. Figure 5a As shown, due to the tubular structure of the second fluid channel 115, the end 120 may be funnel-shaped, for example, to form a converging portion 119, wherein, in a cross-sectional view, the end 120 forming the nozzle opening 116 widens in a curved shape toward the inner wall 117 of the first fluid channel 111.

[0055] When the purge injector assembly operates under pressurized conditions, such as Figure 1 and Figure 4 As shown, air flows from compressor 188 through the engine intake manifold and then into the engine airflow port 122 of the first fluid passage 111. As described above, the boost pressure generates an airflow with a first pressure level P1 in the first fluid passage 111, and the airflow entering the first fluid passage 111 is the working fluid that operates the purge injector assembly 10 under boost pressure conditions. When the airflow reaches the flow shaping unit 20, the airflow velocity increases, and due to this effect, a second pressure level P2 is generated in the second fluid passage 115. In this way, evaporated fuel can be removed from the charcoal canister 110 and flow through the charcoal canister cleaning passage 92, and then into the purge airflow port 118 of the second fluid passage 115. The evaporated fuel stream exits the second fluid passage upon reaching the nozzle opening 116. After the nozzle opening 116, the airflow in the first fluid passage 111 mixes with the fuel vapor from the second fluid passage 115. The mixed fluid flows out of the first fluid passage 111 through the airflow port 112 and then into the intake passage arranged between the intake unit 185 and the compressor 188. Therefore, the airflow is positioned around the nozzle opening 116 in the first fluid passage 111 of the purge injector assembly 10, where the nozzle opening 116 is arranged within the first fluid passage 111 such that the airflow in the first fluid passage 111 flows around the nozzle opening 116. The mixed fluid is drawn into the compressor 188 and becomes part of the airflow from the compressor 188. The main portion of the airflow from the compressor 188 is pressurized and sent to the engine, whereby the evaporated fuel from the charcoal canister is burned. It should be noted that the total amount of evaporated fuel in the airflow from the compressor 188 is very small compared to the amount of air, and this small amount of fuel vapor will not adversely affect the performance of the engine and other systems. It should be understood that the airflow from the compressor 188 into the first fluid passage 111 may also contain a small amount of evaporated fuel.

[0056] exist Figure 5bAn alternative embodiment of the purge jet assembly is shown, wherein the converging portion 119 is formed by a constriction portion 121 within the first fluid passage 111. Furthermore, as... Figure 5b As shown, the flow shaping unit 20 may further include a diverging section 123 arranged along the flow direction after the converging section 119. The diverging section 123 may be formed by a pipe expansion section 125 within the first fluid channel 111. The converging section 119 and the diverging section 123 are conventional methods for controlling the flow within the first fluid channel. Figure 5b As shown, for example, the constriction portion 121 can be formed by molding the inner wall 117 of the first fluid channel 111. Therefore, the fluid channel 111 can be easily molded into the desired configuration during the molding process, such that the constriction portion 121 becomes part of the wall structure of the first fluid channel. Similarly, the expansion portion 125 can also be formed by molding the inner wall 117 of the first fluid channel 111. Alternatively, the constriction portion 121 and the expansion portion 125 can be formed from a single piece of material inserted into the first fluid channel 111.

[0057] like Figure 3 and Figure 4 As shown, the purge injector assembly 10 may further include a first valve 30 disposed in the first fluid passage 111 and located between the engine airflow port 122 and the flow forming unit 20. The first valve 30 is configured to allow fluid to flow from the engine airflow port 122 toward the flow forming unit 20 through the first valve 30, while restricting fluid flow from the flow forming unit 20 toward the engine airflow port 122 through the first valve 30. A second valve 50 may be disposed in the second fluid passage 115. The second valve 50 is configured to allow fluid to flow from the purge airflow port 118 toward the air passage airflow port 112 through the second valve 50, while restricting fluid flow from the air passage airflow port 112 toward the purge airflow port 118 through the second valve 50.

[0058] like Figure 3 and Figure 4 As shown, the second fluid channel 115 establishes fluid communication between the purge airflow port 118 and the air passage airflow port 112. The second fluid channel 115 extends from the second fluid channel position 124 to the first fluid channel position 126, where the second fluid channel position 124 is located between the purge airflow port 118 and the third valve 40, and the first fluid channel position 126 is located between the flow shaping unit 20 and the air passage airflow port 112. In this example, the second fluid channel position 124 is located at the junction of the third fluid channel 113 and the second fluid channel 115. Furthermore, the first fluid channel position 126 is located at the junction of the first fluid channel 111 and the second fluid channel 115.

[0059] A second valve 50 is disposed in the second fluid passage 115. The second valve 50 is configured to allow fluid to flow through the second valve 50 in the direction from the purge airflow port 118 toward the air passage airflow port 112, while simultaneously restricting fluid flow through the second valve 50 in the direction from the air passage airflow port 112 toward the purge airflow port 118. Thus, when the purge injector assembly 10 is under boost pressure via the engine airflow port 122, evaporated fuel is allowed to flow in the second fluid passage 115 from the charcoal canister cleaning passage 92 via the purge airflow port 118 to the air passage airflow port 112. In other words, the first pressure level affecting the assembly 10 forms a second pressure level P2 in the second fluid passage 115. In other words, due to the construction of this component, particularly the first valve 30 and the flow forming unit 20, the compressor 188 generates a first pressure level P1 in the first fluid passage 111, such that the second fluid passage 115 extending between the purge airflow port 118 and the air passage airflow port 112 is at a second pressure level P2, wherein the second pressure level P2 is lower than the first pressure level P1 and also lower than the pressure level in the charcoal canister 110. When the system operates at boost pressure, the second pressure level P2 in the second fluid passage 115 allows the charcoal canister 110 to be emptied through the second fluid passage 115 to the air passage airflow port 112. In other words, the first pressure level P1 generated by the compressor 188 in the first fluid passage 111 forms a lower second pressure level P2 in the second fluid passage 115.

[0060] The second valve 50 can be a check valve. It should also be noted that unless the second fluid passage 115 is restricted by the second valve 50, the second fluid passage 115 can deliver fluid in both directions between the purge airflow port 118 and the air passage airflow port 112.

[0061] As described above, the second fluid channel 115 extends between the first fluid channel 111 and the third fluid channel 113. The second fluid channel 115 establishes fluid communication between the purge airflow port 118 and the air passage airflow port 112, and connects to the purge airflow port 118 via the third fluid channel 113, and also connects to the air passage airflow port 112 via the first fluid channel 111. The second fluid channel 115 thus connects the first fluid channel 111 and the third fluid channel 113. Furthermore, the second fluid channel 115 connects to the third fluid channel 113 at the junction between the purge airflow port and the third valve 40 (corresponding to the second fluid channel position 124), and connects to the first fluid channel at the junction between the flow forming unit 20 and the air passage airflow port 112 (corresponding to the first fluid channel position 126). The position of the second fluid channel position 124 in the third fluid channel 113 can also correspond to the purge airflow port 118. Similarly, the position of the first fluid channel position 126 in the first fluid channel can also correspond to the air passage airflow port 112.

[0062] The second fluid passage 115 and the second valve 50 are configured to restrict the flow of fluid from the air passage airflow port 112 toward the purge airflow port 118 through the second valve 50.

[0063] When the compressor 188 operates in boost mode to generate a boost pressure that causes the purge injector assembly 10 to experience a first pressure level P1, air flows through the first fluid passage 111 from the engine airflow port 122 toward the air passage airflow port 112. In other words, when the compressor operates in boost mode, air flows through the first valve 30 and through the flow shaping unit 20. This creates a second pressure level P2 in the second fluid passage 115 due to the configuration of the flow shaping unit 20. The second pressure level P2 allows fuel vapor to be purged through the second fluid passage 115 during boost engine operation. During boost engine operation, the airflow in the first fluid passage 111 is... Figure 4 The arrow in the diagram indicates that during turbocharged engine operation, the flow of fuel vapor in the second fluid passage 115 is controlled by... Figure 4 The arrow in the text indicates this.

[0064] As described above, the purge jet assembly 10 may further include a third fluid passage 113, such as Figure 3 and Figure 4As shown, the third fluid passage 113 establishes fluid communication between the purge airflow port 118 and the engine airflow port 122. A third valve 40 may be disposed within the third fluid passage 113, located between the engine airflow port 122 and the purge airflow port 118. The third valve 40 is configured to allow fluid to flow from the purge airflow port 118 toward the engine airflow port 122 while simultaneously restricting fluid flow from the engine airflow port 122 toward the purge airflow port 118. This allows evaporated fuel to flow from the charcoal canister cleaning passage 92 to the engine airflow port 122 within the third fluid passage 113 when a low pressure is applied to the engine airflow port 122.

[0065] The purge airflow port 118 can be connected to the charcoal canister cleaning passage 92. As shown, a third fluid passage 113 is connected to the engine airflow port 122 at the junction between the engine airflow port 122 and the first valve 30 in the first fluid passage 111. A third valve 40 is disposed in the third fluid passage 113, located between the engine airflow port 122 and the purge airflow port 118. Further, the third valve 40 is configured to allow fluid to flow from the purge airflow port 118 toward the engine airflow port 122 while restricting fluid flow from the engine airflow port 122 toward the purge airflow port 118. Thus, when the assembly 10 operates under low-pressure conditions via the engine airflow port 122, evaporated fuel is allowed to flow from the charcoal canister cleaning passage 92 to the engine airflow port 122 in the third fluid passage 113. The third valve 40 can be, for example, a check valve. It should also be noted that unless the third fluid passage 113 is restricted by the third valve 40, the third fluid passage 113 can deliver fluid in both directions between the engine airflow port 122 and the purge airflow port 118.

[0066] The third fluid passage 113 establishes fluid communication between the purge airflow port 118 and the engine airflow port 122, and the third fluid passage 113 is connected to the engine airflow port 122 via the first fluid passage 111. In this way, the third fluid passage 113 is connected to the first fluid passage 111. The third fluid passage 113 may be connected to the first fluid passage 111 at the junction located between the first check valve 30 and the engine airflow port 122. However, as an alternative, the third fluid passage 113 establishing fluid communication between the purge airflow port 118 and the engine airflow port 122 may instead be directly and independently connected to the engine intake manifold 104.

[0067] It should also be noted that during the boosted engine operation when the purge injector assembly 10 is under boost pressure, no fluid can flow through the third valve 40 in the third fluid passage 113, because the third valve 40 is configured to restrict fluid flow from the engine airflow port 122 toward the purge airflow port 118 through the third valve 40.

[0068] like Figure 3 As shown, when the purge injector assembly is under low pressure, the third valve 40 is configured to allow fluid to flow from the purge airflow port 118 toward the engine airflow port 122. Thus, during low-pressure engine operation, the charcoal canister 110 can be purged into the engine system 180 via the charcoal canister cleaning passage 92 and the purge injector assembly 10. The above-described configuration of the first fluid passage 111 and the first valve 30 is also readily understood, as the first valve 30 is configured to restrict fluid flow from the flow shaping unit 20 toward the engine airflow port 122, and fuel vapor is restricted from flowing through the first valve 30 in this mode.

[0069] Furthermore, such as Figure 3 and Figure 4 As shown, the purge injector assembly 10 includes a first valve 30 disposed in a first fluid passage 111 and located between the engine airflow port 122 and the flow shaping unit 20. The first valve 30 is configured to allow fluid to flow from the engine airflow port 122 toward the flow shaping unit 20 and the air passage airflow port 112 through the first valve 30, while restricting fluid flow from the flow shaping unit 20 toward the engine airflow port 122 through the first valve. As an example, the first valve 30 may be, for instance, a check valve controlling the flow through the first passage 111.

[0070] Based on the above description of an exemplary embodiment of the purge injector assembly 10, the purge injector assembly 10 provides the possibility of purging the charcoal canister under various operating conditions (i.e., under turbocharged engine conditions and low-pressure conditions). In this way, it becomes feasible to further improve the existing operation of the fuel system and EVAP system. In particular, this disclosure provides a purge injector assembly 10 that can control the purge flow when the engine is operating under both low-pressure and turbocharged conditions. Thus, the exemplary embodiment of the present invention improves the overall performance of the purge injector assembly.

[0071] The purge injector assembly 10 can be constructed as a single unit installed within the vehicle's fuel system. In this way, the functionality of the purge injector assembly 10 can be integrated into a single unit. Such a single unit can be an assembled unit formed from different parts, including necessary flow channels and valves. The fluid channels and flow-forming units can be made of any suitable material, such as plastics, composite materials, and metals.

[0072] like Figure 1 and Figure 2 As shown, the airflow port 112 of the purge injector assembly 10 is typically connected to the intake passage at a location between the intake unit 185 and the compressor 188. However, it should also be readily understood that the purge injector assembly can be installed in other locations within the evaporative fuel purging system. For example, the purge injector assembly 10 can be connected to the intake passage downstream of the compressor 188, but directly connected to the intake unit 185, or at least adjacent to the intake unit 185.

[0073] Depending on the engine configuration, other compressed air sources besides compressors in the form of turbochargers or superchargers may be used. Alternatively, other types of compressor units may be used to generate the working fluid flowing to the purge injector assembly.

[0074] It is understood that the above description is merely exemplary in nature and is not intended to limit the scope of this disclosure, its application, or its use. Although specific embodiments have been described in the specification and illustrated in the drawings, those skilled in the art will understand that various changes can be made and equivalents can be substituted for elements without departing from the scope of this disclosure as defined in the claims. Furthermore, modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the essential scope of this disclosure. Therefore, this disclosure is not intended to be limited to specific examples shown in the drawings and described in the specification as the best mode currently contemplated for carrying out the teachings of this disclosure, and the scope of this disclosure will include any embodiments falling within the foregoing description and the appended claims. Reference numerals in the claims should not be considered as limiting the scope of the claims, and their sole purpose is to facilitate understanding of the claims. Explanation of reference numerals in the attached figures 10 Purge jet assembly 20 Flow forming unit 30 First valve 40 Third valve 50 Second valve 90 Cleaning valve 92 Charcoal canister cleaning channel; 100 Vehicle fuel system 102 Fuel Evaporative Purging System 104 Engine Intake Manifold 110 Charcoal Canister 111 First Fluid Channel 112 Air passage airflow port; 113 Third fluid passage 114 Fresh Air 115 Second Fluid Channel 116 Nozzle opening 117 Inner wall 118 Purge airflow port 119 Convergence section 120 End section 121 Pipe contraction section 122 Engine airflow port 123 Diverging section 124 Second fluid channel location 125 Pipe expansion section 126 First fluid channel location 130 Air filter 132 Air filter ventilation duct 140 Fuel tank 142 Steam exhaust channel 150 Fuel filter 152 Fuel filter passage 180 Engine system 185 Intake unit 188 Compressor

Claims

1. A purge jet assembly (10) for a vehicle, comprising: The first fluid passage (111) has an engine airflow port (122) and an air passage airflow port (112) that are fluidly connected to each other. A second fluid channel (115) is connected to the first fluid channel (111). The second fluid channel (115) has a purge airflow port (118) and a nozzle opening (116) arranged outside the first fluid channel (111). The purge airflow port (118) and the air channel airflow port (112) are in fluid communication with each other. The purge airflow port (118) is configured to connect to the charcoal canister cleaning channel (92), so that evaporated fuel flows from the charcoal canister cleaning channel (92) to the air channel airflow port (112) in the second fluid channel (115). A flow shaping unit (20) is disposed within the first fluid channel (111) between the engine airflow port (122) and the air passage airflow port (112), wherein the flow shaping unit (20) is configured to increase the flow rate of air flowing in the direction from the engine airflow port (122) to the air passage airflow port (112) when a first pressure level (P1) is applied to the engine airflow port (122), thereby subjecting the second fluid channel (115) to a second pressure level (P2) lower than the first pressure level (P1). The second fluid channel (115) extends into the first fluid channel (111), and the nozzle opening (116) is arranged within the first fluid channel (111) and faces the airflow port (112) of the air channel, such that the airflow in the first fluid channel (111) flows through a cross-sectional area surrounding the nozzle opening, wherein the cross-sectional area is between the nozzle opening and the inner wall of the first fluid channel, and the flow shaping unit (20) is disposed within the first fluid channel (111) and relates to the nozzle opening (116). The second fluid channel (115) has a first channel segment within the first fluid channel (111), the first channel segment extending parallel to the first fluid channel (111), and the first channel segment having a consistent diameter along its length.

2. The purge jet assembly (10) according to claim 1, characterized in that, The flow shaping unit (20) includes a converging section (119) configured to increase the flow rate of the airflow from the engine airflow port (122) to the air passage airflow port (112).

3. The purge jet assembly (10) according to claim 2, characterized in that, The converging portion (119) is formed by an end portion (120) located at the downstream end of the first channel segment, thereby giving the nozzle opening (116) a flared shape.

4. The purge jet assembly (10) according to claim 2, characterized in that, The converging portion (119) is formed by the pipe contraction portion (121) within the first fluid channel (111), and the nozzle opening (116) is formed by the first channel segment and has a diameter consistent along its own length.

5. The purge jet assembly (10) according to claim 4, characterized in that, The flow forming unit (20) includes a diverging section (123) arranged along the flow direction after the converging section (119), wherein the diverging section (123) is formed by a pipe expansion section (125) within the first fluid channel (111).

6. The purge jet assembly (10) according to any one of claims 1-5, characterized in that, The second fluid channel (115) further includes a second channel segment and a bend segment, wherein the purge airflow port (118) is connected to the first channel segment via the second channel segment and the bend segment.

7. The purge jet assembly (10) according to claim 6, characterized in that, The second channel segment and / or the bent segment have a consistent diameter along their length.

8. The purge jet assembly (10) according to claim 6, characterized in that, The nozzle opening (116) has a substantially circular cross-sectional shape, and the inner wall (117) of the first fluid passage (111) has a substantially circular cross-sectional shape, such that the airflow in the first fluid passage (111) has a substantially annular cross-sectional shape as it flows around the nozzle opening (116) along the first fluid passage (111) from the engine airflow port (122) toward the air passage airflow port (112).

9. The purge jet assembly (10) according to any one of claims 1-5, characterized in that, The purge jet assembly (10) also includes: A first valve (30) is disposed in the first fluid passage (111) and positioned between the engine airflow port (122) and the flow forming unit (20). The first valve (30) is configured to allow fluid to flow from the engine airflow port (122) toward the flow forming unit (20) through the first valve (30), while restricting fluid from flowing from the flow forming unit (20) toward the engine airflow port (122) through the first valve (30). The second valve (50) is disposed in the second fluid passage (115) and is configured to allow fluid to flow from the purge airflow port (118) toward the air passage airflow port (112) through the second valve (50), while restricting fluid from flowing from the air passage airflow port (112) toward the purge airflow port (118) through the second valve (50).

10. The purge jet assembly (10) according to claim 9, characterized in that, The purge jet assembly (10) also includes: A third fluid channel (113) establishes fluid communication between the purge airflow port (118) and the engine airflow port (122); A third valve (40) is disposed in the third fluid passage (113) and located between the engine airflow port (122) and the purge airflow port (118). The third valve (40) is configured to allow fluid to flow from the purge airflow port (118) toward the engine airflow port (122) through the third valve (40), while restricting fluid flow from the engine airflow port (122) toward the purge airflow port (118) through the third valve (40). This allows evaporated fuel to flow from the charcoal canister cleaning passage (92) to the engine airflow port (122) in the third fluid passage (113) when a low pressure is applied to the engine airflow port (122).

11. The purge jet assembly (10) according to any one of claims 1-5, characterized in that, The purge jet assembly (10) is a single, assembled unit.

12. A fuel vapor purging system (102), comprising: Fuel tank (104) for storing fuel; A charcoal canister (110) is used to absorb evaporated fuel discharged from the fuel tank (104) and is adapted to desorb the evaporated fuel. The charcoal canister (110) is connected to the fuel tank (104) via a vapor discharge passage (142). A charcoal canister cleaning passage (92) extending from the charcoal canister (110) to the engine intake manifold (104); and A cleaning valve (90) is disposed in the cleaning channel (92) of the charcoal canister and is configured to regulate the flow of evaporated fuel in the cleaning channel (92); The system (102) further includes a purge injector assembly (10) according to any one of claims 1-11, the purge injector assembly (10) being disposed between the purge valve (90) and the engine intake manifold (104).

13. A method for injecting vaporized fuel in a vehicle having a purge injector assembly (10) according to any one of claims 1-11, wherein, The method includes the following steps: An airflow is provided in the first fluid passage (111) of the purge jet assembly (10) surrounding a nozzle opening (116), wherein the nozzle opening (116) is disposed within the first fluid passage (111) such that the airflow in the first fluid passage (111) flows around the nozzle opening (116).

14. A vehicle, wherein, The vehicle includes a purge injector assembly (10) according to any one of claims 1-11.

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