Oil tank leakage diagnosis device

Abstract

The utility model discloses an oil tank leakage diagnosis device, which belongs to the technical field of oil tank leakage diagnosis and comprises a shell, and a plurality of cavities for installation are arranged in the shell. The air pump is mounted in one of the cavities of the shell; the electromagnetic switching valve is installed in the other cavity of the shell, a movable valve element part is arranged at the end of the electromagnetic switching valve, and a port of the end of the electromagnetic switching valve is blocked or opened through the movable valve element part; the upper cover and the shell are connected and formed, a connector part is arranged in the upper cover, and the connector part is used for being connected with a whole vehicle wire harness and controlling the whole vehicle wire harness; and a reference hole piece, wherein the reference hole piece is installed on the shell. The oil tank leakage detection device is provided with a modularized air pump and electromagnetic switching valve structure, production testing can be carried out independently, assembly assembling is convenient, rapid diagnosis of oil tank leakage is achieved, and the oil tank leakage detection device is stable in structure, easy to operate and capable of being produced in batches.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the oil tank leakage diagnosis technical field especially relates to an oil tank leakage diagnosis device. BACKGROUND

[0002] According to the regulation requirement of light-duty vehicle national six (GB18352.6), the OBD leakage diagnosis needs to be carried out to vehicle fuel evaporation system, and when the leakage amount is greater than the regulation limit, the light alarm is carried out.In the vehicle starting process, the system must carry out leakage test to ensure that fuel vapor does not leak to the atmosphere.

[0003] In order to adapt to the diagnosis demand of fuel evaporation system of various internal combustion engine vehicles (such as pure fuel vehicle, plug-in hybrid and extended range hybrid vehicle), the current mainstream technical route is active diagnosis route, which utilizes the vacuum or pressure of gas pump to the system, utilizes electromagnetic switching valve to seal or channel switching of the system, and judges whether the system exists any leakage by comparing pressure parameters with built-in standard hole or monitoring pressure decay parameters under sealing condition, which is the technical principle of oil tank leakage diagnosis, but the prior art does not propose a specific structure for mass production to realize the leakage diagnosis of oil tank. UTILITY MODEL CONTENTS

[0004] The utility model overcomes the insufficient of prior art, provides an oil tank leakage diagnosis device to solve the prior art existing problems.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the technical scheme of a kind of oil tank leakage diagnosis device, comprising

[0006] Shell, the shell is equipped with several cavities for installation;

[0007] Gas pump, the gas pump is installed in one cavity of the shell;

[0008] Electromagnetic switching valve, the electromagnetic switching valve is installed in another cavity of the shell, the end of the electromagnetic switching valve is provided with dynamic valve core part, and the end port of the electromagnetic switching valve is blocked or opened by the dynamic valve core part;

[0009] Upper cover, the upper cover is connected with the shell formation, the connector part is arranged in the upper cover, the connector part is connected with vehicle wiring harness and is controlled;

[0010] Reference hole piece, the reference hole piece is installed on the shell.

[0011] In a preferred embodiment of the utility model, the shell is internally provided with a first through hole, a second through hole and a mounting hole, the first through hole is used for mounting the air pump, the second through hole is used for mounting the electromagnetic switch valve, and the mounting hole is used for mounting the reference hole part.

[0012] In a preferred embodiment of the utility model, the shell bottom is provided with an internal passage, which is communicated with the first through hole, the second through hole and the mounting hole.

[0013] In a preferred embodiment of the utility model, the shell is provided with an atmosphere port and a carbon tank port, the atmosphere port is communicated with the external atmosphere environment, and the carbon tank port is connected with the carbon tank and the oil tank system through a pipeline.

[0014] In a preferred embodiment of the utility model, the air pump is provided with an air inlet and an air outlet, the air inlet is communicated with the atmosphere port, and the air outlet is mounted in the first through hole to mount the air pump.

[0015] In a preferred embodiment of the utility model, the electromagnetic switch valve is mounted in another cavity of the shell through a plurality of sealing parts.

[0016] In a preferred embodiment of the utility model, the moving valve core part includes a valve rod, an upper sealing sheet and a lower sealing sheet, when the electromagnetic switch valve is not powered, the upper sealing sheet and the lower sealing sheet block the end port of the electromagnetic switch valve, and when the electromagnetic switch valve is powered, the upper sealing sheet and the lower sealing sheet open the end port of the electromagnetic switch valve to block the atmosphere port.

[0017] In a preferred embodiment of the utility model, the upper sealing sheet and the lower sealing sheet are both arranged on the valve rod and synchronously move with the valve rod.

[0018] In a preferred embodiment of the utility model, the connector part includes a connection terminal and a PCB board, the connection terminal is matched with the whole vehicle wire harness, the PCB board is communicated with the power supply port of the air pump and the power supply port of the electromagnetic switch valve and the connection terminal, and the vehicle controls the air pump and the electromagnetic switch valve.

[0019] In a preferred embodiment of the utility model, the air pump is a vane pump driven by a motor.

[0020] The utility model solves the defects in the background art and has the following beneficial effects:

[0021] The oil tank leakage diagnosis device has a modularized air pump and electromagnetic switching valve structure, can be separately produced and tested, is convenient for assembly, realizes rapid diagnosis of oil tank leakage, and is stable in structure, simple to operate and capable of being produced in batches. BRIEF DESCRIPTION OF DRAWINGS

[0022] The utility model is further described below in combination with the drawings and embodiments;

[0023] Figure 1 It is whole structure schematic diagram of preferred embodiment of the utility model;

[0024] Figure 2 It is whole sectional view of preferred embodiment of the utility model;

[0025] Figure 3 It is structure schematic diagram of shell of preferred embodiment of the utility model;

[0026] Figure 4 It is structure schematic diagram of air pump of preferred embodiment of the utility model;

[0027] Figure 5 It is structure schematic diagram of electromagnetic switching valve of preferred embodiment of the utility model;

[0028] Figure 6 It is structure schematic diagram of dynamic valve core part of preferred embodiment of the utility model;

[0029] Figure 7 It is structure schematic diagram of connector part of preferred embodiment of the utility model;

[0030] In the drawing: 10, shell;11, first through hole;12, second through hole;13, mounting hole;14, internal passage;15, atmospheric port;16, carbon canister port;20, air pump;21, air inlet;22, air outlet;30, electromagnetic switching valve;31, dynamic valve core part;311, valve stem;312, upper sealing sheet;313, lower sealing sheet;40, upper cover;41, connector part;411, connection terminal;412, PCB board;50, reference hole piece;60, sealing piece. DETAILED DESCRIPTION

[0031] The utility model is further described below in combination with the drawings and embodiments, so that those skilled in the art can better understand the utility model and can be implemented, but the embodiment is not as the limitation of the utility model.

[0032] The oil tank leakage diagnosis device provided by the embodiment adopts a modular structure design, can be tested separately, facilitates assembly, realizes rapid diagnosis of oil tank leakage, and has stable structure, simple operation and batch production.

[0033] In combination Figures 1 to 7 As shown in the drawings, the oil tank leakage diagnosis device comprises a shell 10, an air pump 20, an electromagnetic switching valve 30, an upper cover 40 and a reference hole piece 50. The shell 10 is provided with a plurality of cavities for installation. The air pump 20 and the electromagnetic switching valve 30 are respectively installed in adjacent cavities of the shell 10. The upper cover 40 is connected to the shell 10. In the embodiment, the upper cover 40 and the shell 10 are connected by welding or fasteners. The reference hole piece 50 is a metal piece with a known leakage hole diameter, which is installed on the shell 10.

[0034] In the embodiment, the air pump 20 is a motor-driven vane pump, and the electromagnetic switching valve 30 is a 2-position electromagnetic valve controlled by an electromagnetic coil.

[0035] In combination Figure 2 With Figure 3 As shown in the drawings, the shell 10 is provided with a first through hole 11, a second through hole 12 and a mounting hole 13. The first through hole 11 is used for mounting the air pump 20. The second through hole 12 is used for mounting the electromagnetic switching valve 30. The mounting hole 13 is used for mounting the reference hole piece 50. The bottom of the shell 10 is provided with an internal passage 14, which is in communication with the first through hole 11, the second through hole 12 and the mounting hole 13. In the embodiment, the second through hole 12 and the mounting hole 13 are located in the same cavity.

[0036] Further, the shell 10 is provided with an atmosphere port 15 and a carbon canister port 16. The atmosphere port 15 is in communication with the external atmosphere. The carbon canister port 16 is connected to the carbon canister and the oil tank system through a pipeline. In the embodiment, the atmosphere port 15 is in communication with the external atmosphere through an air filter.

[0037] In combination Figure 2 With Figure 4 As shown in the drawings, the air pump 20 is provided with an air inlet 21 and an air outlet 22. The air inlet 21 is in communication with the atmosphere port 15. The air outlet 22 is installed in the first through hole 11 to mount the air pump 20. In the embodiment, the air pump 20 is a motor-driven vane pump. The positive electrode of the motor is connected to the positive electrode of the power supply. The negative electrode of the motor is connected to the negative electrode of the power supply.

[0038] In combination Figure 2 , Figure 5 and Figure 6As shown, the end of the electromagnetic switching valve 30 of the present embodiment is provided with a movable spool part 31, which blocks or opens the end port of the electromagnetic switching valve 30, and the movable spool part 31 comprises a valve rod 311, an upper sealing piece 312, and a lower sealing piece 313. When the electromagnetic switching valve 30 is not powered, the upper sealing piece 312 and the lower sealing piece 313 block the end port of the electromagnetic switching valve 30; when the electromagnetic switching valve 30 is powered, the upper sealing piece 312 and the lower sealing piece 313 open the end port of the electromagnetic switching valve 30 and block the atmospheric port 15.

[0039] Specifically, the upper sealing piece 312 and the lower sealing piece 313 are both arranged on the valve rod 311 and move synchronously with the valve rod 311.

[0040] In the present embodiment, the electromagnetic switching valve 30 is installed in the cavity of the housing 10 through a plurality of sealing members 60.

[0041] In combination Figure 2 With Figure 7 As shown, the upper cover 40 of the present embodiment is provided with a connector part 41, which is used to connect with the vehicle wiring harness and perform control, and the connector part 41 comprises a connection terminal 411 and a PCB board 412. The connection terminal 411 is paired with the vehicle wiring harness, and the PCB board 412 communicates the power supply port of the air pump 20 and the power supply port of the electromagnetic switching valve 30 with the connection terminal 411, so as to realize the control of the vehicle on the air pump 20 and the electromagnetic switching valve 30. In addition to electrical connection, the connector part 41 of the present embodiment can also increase diodes, resistors, capacitors, and other components, so as to meet the higher EMC level requirement.

[0042] In actual use, when the air pump 20 is powered on, the port of the electromagnetic switching valve 30 is blocked by the movable spool part 31, and the air flows in the direction of the atmospheric port 15, the air inlet 21, the air outlet 22, the internal passage 14, and the reference hole member 50. After the airflow flows out of the reference hole member 50, it can flow to the atmospheric port 15 and the carbon can port 16 at the same time. However, since the vehicle fuel evaporation system connected with the carbon can port 16 is approximately closed, and the external atmosphere connected with the atmospheric port 15 has small flow resistance, most of the airflow will flow out of the atmospheric port 15. In this working condition, the minimum cross-sectional area of the entire passage is the reference hole member 50. When the load of the air pump 20 is stable, the reference pump current can be obtained by monitoring the load parameter (such as the current of the air pump 20) of the air pump 20.

[0043] When the air pump 20 is powered on and the electromagnetic switch valve 30 is also powered on, the electromagnetic coil drives the valve core part 31 to move up to the upper dead point, at this time the port of the electromagnetic switch valve 30 is opened, and the area of the port is much larger than the area of the reference orifice 50, so the air is pumped into the carbon canister and the entire fuel evaporation system along the path of the atmospheric port 15, the air inlet 21, the air outlet 22, the internal channel 14, the port of the electromagnetic switch valve 30, and the carbon canister port 16, the pressure in the fuel evaporation system initially rises, and after a period of time, the pressure approaches stability, and the actual pump current can be obtained by monitoring the load parameter (such as the current of the air pump 20) of the air pump 20.

[0044] Since the functional relationship among the pressure, flow rate, and rotational speed of the air pump 20 is stable, the rotational speed of the air pump 20 can be converted by detecting the pump current, so as to calculate the flow rate and pressure of the air pump 20 by table lookup, and according to the Bernoulli equation, the actual equivalent leakage area of the fuel evaporation system can be calculated by knowing the aperture of the reference orifice 50. Finally, the vehicle ECU performs logical judgment on whether the actual leakage exceeds the threshold value allowed by the regulations, and performs light-on warning and the like to remind.

[0045] Obviously, the above embodiments are only examples for clearly illustrating, and are not limited to the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. It is not necessary and impossible to enumerate all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. An oil tank leakage diagnosing apparatus characterized by comprising: Comprising A shell (10) is provided with several cavities for installation inside; A gas pump (20) is installed in one of the cavities of the shell (10); An electromagnetic switching valve (30) is installed in another cavity of the shell (10), and the end of the electromagnetic switching valve (30) is provided with a moving valve core (31) to block or open the end port of the electromagnetic switching valve (30); An upper cover (40) is connected and formed with the shell (10), and the connector (41) is provided inside the upper cover (40) to connect the vehicle wire harness and control; A reference hole piece (50) is installed on the shell (10).

2. An oil tank leakage diagnosing apparatus according to claim 1, characterized by The shell (10) is provided with a first through hole (11), a second through hole (12) and a mounting hole (13), the first through hole (11) is used to install the gas pump (20), the second through hole (12) is used to install the electromagnetic switching valve (30), and the mounting hole (13) is used to install the reference hole piece (50).

3. An oil tank leakage diagnosing apparatus according to claim 2, characterized by The bottom of the shell (10) is provided with an internal passage (14) which communicates with the first through hole (11), the second through hole (12) and the mounting hole (13).

4. An oil tank leakage diagnosing apparatus according to claim 2, characterized by The shell (10) is provided with an atmospheric port (15) and a carbon canister port (16), the atmospheric port (15) communicates with the external atmosphere, and the carbon canister port (16) is connected with the carbon canister and the tank system through a pipeline.

5. An oil tank leakage diagnosing apparatus according to claim 4, characterized by The gas pump (20) is provided with an air inlet (21) and an air outlet (22), the air inlet (21) communicates with the atmospheric port (15), and the air outlet (22) is installed in the first through hole (11) to install the gas pump (20).

6. The tank leak diagnostic apparatus of claim 1 wherein, The electromagnetic switching valve (30) is installed in another cavity of the shell (10) through several sealing pieces (60).

7. An oil tank leakage diagnosing apparatus according to claim 4, wherein The moving valve core (31) includes a valve rod (311), an upper sealing piece (312) and a lower sealing piece (313), when the electromagnetic switching valve (30) is not powered, the upper sealing piece (312) and the lower sealing piece (313) block the end port of the electromagnetic switching valve (30), when the electromagnetic switching valve (30) is powered, the upper sealing piece (312) and the lower sealing piece (313) open the end port of the electromagnetic switching valve (30) to block the atmospheric port (15).

8. An oil tank leakage diagnosing apparatus according to claim 7, wherein The upper sealing piece (312) and the lower sealing piece (313) are provided on the valve rod (311) and move synchronously with the valve rod (311).

9. The tank leak diagnostic apparatus of claim 1 wherein, The connector part (41) comprises a connection terminal (411) and a PCB board (412), the connection terminal (411) is matched with a whole vehicle wire harness, and the PCB board (412) communicates power supply ports of the air pump (20) and the electromagnetic switching valve (30) with the connection terminal (411), so as to realize control of the air pump (20) and the electromagnetic switching valve (30) by a vehicle.

10. The tank leak diagnostic apparatus of claim 1 wherein, The air pump (20) is a motor-driven vane pump.

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