A carbon can solenoid valve desorption pipeline integrated assembly

Abstract

The application discloses a kind of carbon tank solenoid valve desorption pipeline integrated assembly, belong to automobile fuel evaporation control system technical field.The integrated assembly includes carbon tank solenoid valve, venturi, carbon tank joint, tee and connecting hose.Carbon tank solenoid valve has public interface, positive pressure interface and negative pressure interface, public interface is communicated with carbon tank outlet.Negative pressure desorption route is from public interface, and venturi is connected into air intake manifold;Positive pressure desorption route is from public interface, and carbon tank joint and first hose are connected into air intake pipe after tee, and tee is connected into intercooler by second hose.The application realizes positive pressure desorption and negative pressure desorption function by integrated carbon tank solenoid valve, reduces the number of parts, reduces occupied space, and simplifies pipeline layout.

Description

Technical Field

[0001] This invention relates to the field of automotive fuel evaporation control system technology, and more specifically to an integrated assembly of a carbon canister solenoid valve desorption pipeline for an engine carbon canister desorption system. Background Technology

[0002] Fuel in a car's fuel tank evaporates into fuel vapor. To prevent fuel vapor from evaporating into the atmosphere and causing fuel waste and environmental pollution, modern cars are equipped with an evaporative fuel absorption control system (EVAP). This system uses a carbon canister to adsorb the fuel vapor that evaporates from the fuel tank. When the engine starts, the carbon canister solenoid valve opens, bringing the adsorbed fuel vapor and fresh air into the engine cylinders for combustion.

[0003] For engines equipped with turbochargers, the carbon canister desorption system needs to select different desorption paths depending on the engine's operating conditions. Specifically, under engine idling or low-load conditions (when the throttle opening is small and the intake manifold is under negative pressure), fuel vapor can directly enter the intake manifold from the carbon canister via the solenoid valve through the negative pressure route. However, under engine high-load or turbocharged conditions (when the intake manifold is under positive pressure), the negative pressure route cannot achieve desorption. Instead, the fuel vapor needs to be guided to the intake manifold before the turbocharger through the positive pressure route. The negative pressure before the turbocharger draws in the fuel vapor, which is then pressurized by the turbocharger, cooled by the intercooler, and enters the intake manifold through the throttle to participate in combustion.

[0004] In existing technologies, to achieve both positive and negative pressure desorption functions, multiple independent components are typically required, including a carbon canister solenoid valve, multiple carbon canister connectors, tee fittings, and connecting pipelines. These components are interconnected via pipe fittings or flexible hoses, which presents the following drawbacks: (1) The large number of parts and the large amount of space occupied in the engine compartment make it difficult to achieve a compact layout of the engine compartment.

[0005] (2) The components need to be connected by multiple pipe joints and hoses, resulting in many connection nodes, a large amount of assembly work, and potential fuel vapor leakage at each connection point.

[0006] (3) The pipeline layout is complex, with each pipe section intersecting with the others, which increases the difficulty of pipeline design and layout.

[0007] To address the aforementioned issues, some existing technologies have attempted to reduce the number of components through integrated design. For example, Chinese utility model patent CN209163960U discloses a dual-path desorption system, which includes a three-way valve, a first pressure sensor, a first desorption tube, a second desorption tube, an inflation tube, and a venturi tube. The first connection end of the three-way valve is connected to the carbon canister solenoid valve, the second connection end of the three-way valve is connected to one end of the first desorption tube, and the other end of the first desorption tube is connected to the input end of the venturi tube. Although this solution achieves dual-path desorption, it still requires the additional three-way valve and pressure sensor, making the system configuration relatively complex.

[0008] For example, Chinese utility model patent CN210217949U discloses a fuel vapor desorption pipeline structure for automobiles, which includes a negative pressure desorption route and a positive pressure desorption route. The negative pressure desorption route includes a carbon canister, desorption pipe I, a carbon canister solenoid valve, a tee pipe, a carbon canister pipe, a carbon canister connector I, and an intake manifold connected in sequence; the positive pressure desorption route includes a carbon canister, desorption pipe I, a carbon canister solenoid valve, a tee pipe, a desorption pipe II, a venturi pipe, and a turbocharger intake pipe. Although this solution achieves both positive and negative pressure desorption functions, it still requires a separate tee pipe and multiple carbon canister connectors, resulting in a relatively large number of components. Furthermore, the carbon canister solenoid valve itself does not integrate a distribution function, requiring an external tee pipe for airflow distribution. Summary of the Invention

[0009] The present invention aims to provide an integrated component for the desorption pipeline of a carbon canister solenoid valve. This component achieves both positive and negative pressure desorption functions through an integrated carbon canister solenoid valve, eliminating the need for multiple carbon canister joints and tee joints for airflow distribution. This reduces the number of components in the engine carbon canister desorption device, reduces space occupation, simplifies the connection structure of the desorption pipeline, reduces connection nodes, and lowers the risk of fuel vapor leakage.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: An integrated assembly for a carbon canister solenoid valve desorption pipeline includes a carbon canister solenoid valve, a venturi tube, a carbon canister connector, and a tee. The carbon canister solenoid valve has a common interface, a negative pressure interface, and a positive pressure interface. The common interface is used to connect to the outlet of the carbon canister. The venturi tube is connected between the negative pressure interface and the engine intake manifold. The carbon canister connector is connected to the outlet end of the positive pressure interface. The tee has one inlet and two outlets. The inlet of the tee is connected to the outlet of the carbon canister connector, one outlet of the tee is connected to the engine intake manifold, and the other outlet of the tee is connected to the intercooler.

[0011] Furthermore, it also includes a first hose and a second hose, wherein the carbon canister connector is connected to the inlet of the tee via the first hose, and the other outlet of the tee is connected to the intercooler via the second hose.

[0012] Furthermore, the carbon canister connector is fixedly installed at the positive pressure interface of the carbon canister solenoid valve. The two can be connected using a split assembly quick-connect structure, or they can be integrated into a single structure.

[0013] Furthermore, the carbon canister solenoid valve is internally equipped with a valve core and an electromagnetic coil. Under the excitation or demagnetization control of the electromagnetic coil, the valve core can selectively connect the common interface to the negative pressure interface or the positive pressure interface.

[0014] Furthermore, when the solenoid coil of the carbon canister solenoid valve is de-energized, the valve core blocks the positive pressure port, connecting the common port and the negative pressure port; when the solenoid coil is energized, the valve core blocks the negative pressure port, connecting the common port and the positive pressure port.

[0015] Furthermore, the common interface, the negative pressure interface, and the positive pressure interface are all quick-connect connectors.

[0016] Compared with the prior art, the present invention has the following advantages: (1) The present invention replaces the carbon canister solenoid valve, external distribution valve or multiple carbon canister joints that need to be set independently in the traditional structure with an integrated carbon canister solenoid valve with a built-in selection valve core, which greatly reduces the number of parts in the engine compartment, reduces the space occupied, and is conducive to the compact layout of the whole vehicle.

[0017] (2) This invention connects the output end of the positive pressure desorption pipeline to a valveless tee, which connects the intake pipe at the front end of the turbocharger and the intercooler before the throttle valve at the rear end of the turbocharger. By utilizing the different pressure difference when the turbocharger starts and stops, the fuel vapor is naturally diverted and buffered, solving the specific technical problem of where residual fuel vapor has nowhere to be discharged after the turbocharger stops working.

[0018] (3) The present invention reduces external pipe joints and independent components, thereby significantly reducing the risk of fuel vapor leakage and improving the overall sealing performance and operational reliability of the EVAP system.

[0019] (4) The carbon canister solenoid valve of the present invention adopts a simple internal valve core action logic of "power off to provide negative pressure, power on to provide positive pressure", which does not require an additional external pressure sensor or a complex electronic switching mechanism, thus reducing the ECU control burden and improving operational stability. Attached Figure Description

[0020] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0021] Figure 1 This is a schematic diagram of the structure of the carbon canister solenoid valve desorption pipeline integrated assembly of the present invention.

[0022] Figure 2 This is a schematic diagram illustrating the installation principle of the carbon canister solenoid valve desorption pipeline integrated assembly of the present invention.

[0023] Figure 3 This is a three-dimensional structural diagram of the carbon canister solenoid valve of the present invention.

[0024] Figure 4 This is a schematic diagram of the internal structure of the carbon canister solenoid valve of the present invention.

[0025] Among them, the number is: 1—Carbon canister solenoid valve, 2—Venturi tube, 3—Carbon canister connector, 4—First hose, 5—T-fitting, 6—Second hose, 101—Common interface, 102—Negative pressure interface, 103—Positive pressure interface. Detailed Implementation

[0026] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below with reference to specific illustrations.

[0027] Implementation Method 1 like Figure 1 , Figure 2 as well as Figure 3 As shown, this embodiment provides an integrated assembly for the desorption pipeline of a carbon canister solenoid valve, including a carbon canister solenoid valve 1, a venturi tube 2, a carbon canister connector 3, a first flexible hose 4, a tee 5, and a second flexible hose 6.

[0028] The carbon canister solenoid valve 1 has a common interface 101, a negative pressure interface 102, and a positive pressure interface 103. The common interface 101 is located at one end of the carbon canister solenoid valve 1, and the negative pressure interface 102 and the positive pressure interface 103 are respectively located on both sides of the other end of the carbon canister solenoid valve 1.

[0029] Furthermore, in terms of connection method, the common interface 101 is connected to the outlet of the carbon canister through a pipeline; one end of the venturi tube 2 is connected to the negative pressure interface 102 of the carbon canister solenoid valve 1, and the other end is connected to the engine intake manifold 7; one end of the carbon canister connector 3 is fixedly installed at the positive pressure interface 103 of the carbon canister solenoid valve 1, and the other end is connected to one inlet of the tee 5 through the first flexible hose 4.

[0030] This tee 5 is a valveless tee connector with two outlets. One of the outlets is connected to the engine intake manifold via a pipe. It should be noted that the "intake manifold" here specifically refers to the intake manifold section located upstream of the turbocharger.

[0031] Another outlet is connected to the intercooler via a second hose 6. The term "intercooler" here specifically refers to the intercooler connected between the turbocharger outlet and the upstream of the throttle valve.

[0032] This innovative connection method utilizes the pressure difference before and after the booster to distribute airflow.

[0033] In this embodiment, the carbon canister connector 3 and the positive pressure interface 103 can be assembled separately. The two are connected by a mature and stable quick-connect structure, which allows the use of existing mature carbon canister solenoid valve housings for component assembly, thereby reducing the overall production cost.

[0034] Example 2: like Figure 4 As shown, in another embodiment of the present invention, the carbon canister solenoid valve 1 is provided with a valve core and an electromagnetic coil inside.

[0035] In this example, the carbon canister solenoid valve 1 is specifically configured to perform the following operating logic: When the solenoid coil is de-energized, the valve core is in its initial position under the elastic force of the internal reset spring. At this time, the blocking block on the valve core blocks the positive pressure port 103, while the negative pressure port 102 is in the open state. When the solenoid coil is energized, the electromagnetic force generated by the solenoid coil overcomes the spring force and drives the valve core to move, causing the blocking block on the valve core to move and block the negative pressure port 102, while opening the positive pressure port 103.

[0036] Based on this logic control scheme, the carbon canister solenoid valve 1 can selectively allocate the desorption gas flow path internally by controlling the on / off state of the solenoid coil, without the need for an external switching valve.

[0037] Example 3: In another embodiment of the present invention, the common interface 101, negative pressure interface 102, and positive pressure interface 103 of the carbon canister solenoid valve 1 are all configured as quick-connect fittings to facilitate quick connection with the carbon canister, venturi tube 2, and hoses 4 and 6, thereby improving assembly efficiency. Simultaneously, the connection points at both ends of the venturi tube 2 also employ quick-connect fittings, enabling modular and rapid assembly.

[0038] Example 4: In another embodiment of the present invention, the carbon canister connector 3 and the positive pressure interface 103 of the carbon canister solenoid valve 1 can also be integrated into a single structure. If the carbon canister connector 3 and the positive pressure interface 103 are manufactured using a single molding process, the number of connection nodes can be further reduced, and the overall integrity and sealing performance of the structure can be improved.

[0039] Implementation Method 5 This example provides a specific operation and control scheme for the carbon canister solenoid valve desorption pipeline integrated component scheme formed by the above example solution.

[0040] like Figure 2 and Figure 4 As shown, after the engine starts, the engine control unit (ECU) determines the required desorption mode based on the pressure state in the intake manifold and the working state of the turbocharger.

[0041] (1) Negative pressure desorption mode under idling or low load conditions: When the engine is idling or under light load, the throttle opening is small, and the intake manifold is under negative pressure. At this time, the ECU controls the carbon canister solenoid valve 1 to be de-energized, and the valve core inside the carbon canister solenoid valve 1 blocks the positive pressure port 103, keeping the common port 101 connected to the negative pressure port 102.

[0042] At this point, the fuel vapor adsorbed in the carbon canister, under the suction effect of the negative pressure in the intake manifold, enters the carbon canister solenoid valve 1 through the common interface 101, flows out from the negative pressure interface 102, and enters the intake manifold through the Venturi tube 2. In this negative pressure desorption route, the Venturi tube 2 only serves as a physical conduction channel for fuel vapor, playing a role in maintaining stable airflow transmission, and does not utilize the Venturi effect to generate additional suction negative pressure. The fuel vapor ultimately enters the engine cylinder with fresh air to participate in combustion.

[0043] (2) Positive pressure desorption mode under high load or pressurization conditions: When the engine is under high load or turbocharged conditions, the intake manifold changes from negative pressure to positive pressure, and the negative pressure desorption path cannot function due to the disappearance of the pressure difference. At this time, the ECU controls the carbon canister solenoid valve 1 to be energized. The valve core inside the carbon canister solenoid valve 1 is activated by electromagnetic force, blocking the negative pressure port 102 and connecting the common port 101 with the positive pressure port 103.

[0044] Fuel vapor adsorbed in the carbon canister enters the carbon canister solenoid valve 1 through the common interface 101, flows out from the positive pressure interface 103, and reaches the valveless tee 5 through the carbon canister connector 3 and the first hose 4. The fuel vapor reaching the tee 5 is naturally divided into two paths due to the pressure difference between the two ends of the pipeline: one path enters the intake manifold before the turbocharger through one outlet of the tee 5, and then enters the engine after being pressurized by the turbocharger; the other path enters the intercooler through the second hose 6.

[0045] (3) Residual steam treatment mode under special working conditions (the core function of the second hose 6): Especially during the process of the turbocharger about to stop working or the sudden switching of the positive pressure port 103 of the carbon canister solenoid valve 1 from open to closed due to a sudden change in operating conditions, some fuel vapor that has already flowed out of the positive pressure port 103 will remain in the pipeline. At this time, since the turbocharger has stopped working, the intake pipe at the front end of the turbocharger can no longer provide continuous negative pressure suction; at this time, this part of the residual high-temperature fuel vapor will be naturally and smoothly guided to the intercooler through the second hose 6 due to the pressure difference. Since the intercooler is usually located between the turbocharger outlet and the throttle valve, and pressurized low-temperature air flows inside, the residual fuel vapor can be quickly cooled after entering the intercooler and re-enter the intake manifold with the airflow. This innovative design effectively solves the problem of residual fuel vapor having nowhere to be discharged or being discharged incompletely when the turbocharger stops suddenly in traditional pipelines.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. An integrated assembly for the desorption pipeline of a carbon canister solenoid valve, characterized in that, include: A carbon canister solenoid valve (1) has a common port (101), a negative pressure port (102) and a positive pressure port (103), wherein the common port (101) is used to connect to the outlet of the carbon canister; Venturi tube (2), the Venturi tube (2) is connected between the negative pressure port (102) and the engine intake manifold; Carbon canister connector (3), which is connected to the outlet end of the positive pressure port (103); The three-way valve (5) has one inlet and two outlets. The inlet of the three-way valve (5) is connected to the outlet of the carbon canister connector (3). One outlet of the three-way valve (5) is connected to the engine intake pipe. The other outlet of the three-way valve (5) is connected to the intercooler.

2. The carbon canister solenoid valve desorption pipeline integrated assembly according to claim 1, characterized in that: It also includes a first hose (4) and a second hose (6), the carbon canister connector (3) is connected to the inlet of the tee (5) through the first hose (4), and the other outlet of the tee (5) is connected to the intercooler through the second hose (6).

3. The carbon canister solenoid valve desorption pipeline integrated assembly according to claim 1, characterized in that: The carbon canister connector (3) is fixedly installed at the positive pressure port (103) of the carbon canister solenoid valve (1), and the carbon canister connector (3) and the positive pressure port (103) are connected by a split assembly quick-connect structure, or the two are integrated into a single structure.

4. The carbon canister solenoid valve desorption pipeline integrated assembly according to claim 1, characterized in that: The carbon canister solenoid valve (1) is equipped with a valve core and an electromagnetic coil. Under the excitation or demagnetization control of the electromagnetic coil, the valve core can selectively connect the common interface (101) to the negative pressure interface (102) or the positive pressure interface (103).

5. The carbon canister solenoid valve desorption pipeline integrated assembly according to claim 4, characterized in that: When the solenoid coil of the carbon canister solenoid valve (1) is de-energized, the valve core blocks the positive pressure port (103), making the common port (101) and the negative pressure port (102) connected; when the solenoid coil is energized, the valve core blocks the negative pressure port (102), making the common port (101) and the positive pressure port (103) connected.

6. The carbon canister solenoid valve desorption pipeline integrated assembly according to claim 1, characterized in that: The common interface (101), the negative pressure interface (102) and the positive pressure interface (103) are all quick-connect structures.

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