CN112414722A - Noise test method and noise test bench for fuel evaporation system - Google Patents
Noise test method and noise test bench for fuel evaporation system Download PDFInfo
- Publication number
- CN112414722A CN112414722A CN201910785657.6A CN201910785657A CN112414722A CN 112414722 A CN112414722 A CN 112414722A CN 201910785657 A CN201910785657 A CN 201910785657A CN 112414722 A CN112414722 A CN 112414722A
- Authority
- CN
- China
- Prior art keywords
- noise
- evaporation system
- fuel evaporation
- engine
- noise test
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001704 evaporation Methods 0.000 title claims abstract description 122
- 230000008020 evaporation Effects 0.000 title claims abstract description 122
- 239000000446 fuel Substances 0.000 title claims abstract description 80
- 238000012360 testing method Methods 0.000 title claims abstract description 52
- 238000010998 test method Methods 0.000 title claims abstract description 13
- 238000000034 method Methods 0.000 abstract description 9
- 239000003921 oil Substances 0.000 description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 7
- 229910052799 carbon Inorganic materials 0.000 description 7
- 230000008569 process Effects 0.000 description 5
- 230000003584 silencer Effects 0.000 description 5
- 238000013461 design Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000000737 periodic effect Effects 0.000 description 2
- 230000010349 pulsation Effects 0.000 description 2
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M17/00—Testing of vehicles
- G01M17/007—Wheeled or endless-tracked vehicles
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Testing Of Engines (AREA)
Abstract
The invention discloses a noise test method of a fuel evaporation system and a noise test bench based on the noise test method, wherein the noise test method comprises the following steps: connecting a vacuum source at the position of an evaporation pipeline of the fuel evaporation system close to the engine; starting a vacuum source to enable the vacuum degree of the position, close to the engine, of the evaporation pipeline to reach the vacuum degree of an air inlet manifold when the engine idles; controlling the electromagnetic valve of the fuel evaporation system to open and close periodically; noise of the fuel evaporation system is detected and noise characteristics are analyzed. According to the method, the vacuum degree is provided for the position, close to the engine, of the evaporation pipeline through the vacuum source, so that the fuel evaporation system can work normally when the engine is in a non-working state, the noise of the fuel evaporation system can be tested when the engine does not work, the noise interference of the engine can be avoided, and the noise of the fuel evaporation system can be accurately measured.
Description
Technical Field
The invention relates to the technical field of automobiles, in particular to a noise test method and a noise test bench for a fuel evaporation system.
Background
Referring to fig. 1, fig. 1 is a schematic view of a fuel evaporation system in connection with an engine. The fuel evaporation system comprises an oil tank, a carbon tank, an electromagnetic valve, an evaporation pipeline and other parts. The head end of evaporation pipeline links to each other with the air intake manifold of engine, and the end links to each other with the oil tank, and solenoid valve and carbon tank all set up on evaporation pipeline, and in addition, carbon tank and atmosphere intercommunication. The oil tank is also connected with the engine through a fuel pipeline.
The working process of the fuel evaporation system is as follows: in the process of refueling the oil tank through the refueling port, part of fuel oil is evaporated to form oil gas, and the oil gas is adsorbed on the carbon tank. When the engine idles, the air intake manifold conveys air into the cylinder, so that the vacuum degree is formed in the air intake manifold, and correspondingly, the head end of the evaporation pipeline also forms the same vacuum degree. And the electromagnetic valve is opened and closed periodically, when the electromagnetic valve is opened, fresh air passes through the carbon tank under the action of pressure difference, oil gas adsorbed on the carbon tank is desorbed, the oil gas and the fresh air enter the intake manifold together through the electromagnetic valve, and finally the oil gas and the fresh air are combusted in the cylinder.
In the working process of the fuel evaporation system, on one hand, the pressure pulsation is formed in the evaporation pipeline due to the periodic opening and closing of the electromagnetic valve, the abnormal sound can be formed when the pressure pulsation is transmitted into the vehicle cabin, and on the other hand, the opening and closing noise of the electromagnetic valve can be transmitted into the vehicle cabin through air.
With the development of the NVH (noise Vibration harshness) control technology of the automobile, the noise in the automobile cabin is controlled to be lower and lower, the noise emitted by the fuel evaporation system is gradually highlighted and easily felt by passengers, and at present, in order to adapt to the VI emission standard of China, the flow rate of oil and gas flowing through the electromagnetic valve needs to be increased, and the flow rate is increased to cause the noise of the fuel evaporation system to be larger. Therefore, it is common to provide a muffler on the evaporation pipe to reduce noise of the fuel evaporation system.
The silencer needs to be designed according to the noise characteristic of the fuel evaporation system, however, because the vacuum degree formed by the intake manifold of the engine is a necessary condition for the operation of the fuel evaporation system, the detected noise of the fuel evaporation system is accompanied with the noise of the engine in the prior art, and the two noises are difficult to be distinguished, so the noise characteristic of the fuel evaporation system cannot be accurately detected.
In view of this, how to accurately measure the noise characteristics of the fuel evaporation system is a technical problem to be solved urgently by those skilled in the art.
Disclosure of Invention
In order to solve the technical problem, the invention provides a noise test method of a fuel evaporation system, which comprises the following steps:
the evaporation pipeline of the fuel evaporation system is connected with a vacuum source at a position close to the engine;
starting the vacuum source to enable the vacuum degree of the position, close to the engine, of the evaporation pipeline to reach the vacuum degree of an air inlet manifold when the engine idles;
controlling the electromagnetic valve of the fuel evaporation system to open and close periodically;
noise of the fuel evaporation system is detected and noise characteristics are analyzed.
In the above noise test method, before the vacuum source is connected, the head end of the evaporation line is disconnected from the engine, and the vacuum source is connected to the head end of the evaporation line.
According to the noise test method, during testing, the fuel evaporation system is not installed on the whole vehicle or is detached from the whole vehicle.
According to the noise testing method, in the testing process, the fuel evaporation system is installed on the whole vehicle.
The invention also provides a noise test bench frame of the fuel evaporation system, which comprises a vacuum source, a noise test bench frame and a noise test bench, wherein the vacuum source is connected to the position, close to the engine, of an evaporation pipeline of the fuel evaporation system, so that the vacuum degree of the position, close to the engine, of the evaporation pipeline reaches the vacuum degree of an air inlet manifold when the engine idles; the fuel evaporation system also comprises a control unit used for controlling the electromagnetic valve of the fuel evaporation system to open and close periodically.
The noise test rig as described above, the vacuum source is wrapped with an acoustic barrier.
The noise test bench is characterized in that the vacuum source is connected to the head end of the evaporation pipeline; when the whole vehicle leaves the factory, the head end of the evaporation pipeline is connected with the engine.
The noise test bench rack further comprises a plurality of adapter tubes, wherein the first ends of the adapter tubes are connected with the vacuum source, and the second ends of the adapter tubes are connected with the head end of the evaporation pipeline; the specifications of the first ends of the adapter tubes are consistent, and the specifications of the second ends of the adapter tubes are different.
The noise test bench comprises a noise test bench frame, a noise detection device and a control device, wherein the noise test bench frame also comprises a workbench used for supporting an electromagnetic valve of a fuel evaporation system; the modal frequency of the workbench is larger than 1000 Hz.
The noise test bench frame also comprises a plurality of adapter brackets, the upper ends of the adapter brackets are fixedly connected with the electromagnetic valves of the fuel evaporation systems, and the lower ends of the adapter brackets are fixedly connected on the table surface of the workbench; the specifications of the lower ends of the switching brackets are consistent, and the specifications of the upper ends of the switching brackets are different.
The noise test method and the noise test bench of the fuel evaporation system provided by the invention have the following technical effects:
the noise of the fuel evaporation system can be accurately tested, so that the noise characteristic of the fuel evaporation system can be accurately analyzed, an accurate design basis is provided for the silencer, the silencer with a reasonable structure is favorably designed, the noise of the fuel evaporation system is effectively reduced, and the NVH performance of an automobile is improved.
Drawings
FIG. 1 is a simplified illustration of a fuel vaporization system coupled to an engine of an automobile;
FIG. 2 is a flow chart of a noise testing method provided by the present invention;
FIG. 3 is a simplified diagram of the noise test bed in use according to the present invention.
The reference numerals in fig. 1 to 3 are explained as follows:
01 engine, 02 evaporation pipeline, 03 electromagnetic valve, 04 carbon tank, 05 oil tank;
the device comprises a vacuum source 1, a driving unit 2, a switching tube 3, a workbench 4 and a switching support 5.
Detailed Description
In order to make those skilled in the art better understand the technical solution of the present invention, the technical solution of the present invention is further described in detail below with reference to the accompanying drawings and the detailed description.
The invention provides a noise test method of a fuel evaporation system and a noise test bench frame of the fuel evaporation system, which can accurately test the noise of the fuel evaporation system, thereby accurately analyzing the noise characteristic of the fuel evaporation system, providing accurate design basis for a silencer, and being beneficial to designing the silencer with a reasonable structure, so as to effectively reduce the noise of the fuel evaporation system and improve the NVH performance of an automobile.
Referring to fig. 2, fig. 2 is a flowchart of a noise testing method according to the present invention.
The invention provides a noise testing method, which comprises the following steps:
s1, connecting a vacuum source at the position of an evaporation pipeline of the fuel evaporation system close to the engine;
s2, starting a vacuum source to enable the vacuum degree of the position, close to the engine, of the evaporation pipeline to reach the vacuum degree of an intake manifold when the engine idles;
s3, controlling the electromagnetic valve of the fuel evaporation system to open and close periodically;
s4, detecting noise of the fuel evaporation system and analyzing the noise characteristics.
According to the method, the vacuum degree is provided for the position, close to the engine, of the evaporation pipeline through the vacuum source, so that the fuel evaporation system can work normally when the engine is in a non-working state, the noise of the fuel evaporation system can be tested when the engine does not work, the noise interference of the engine can be avoided, and the noise of the fuel evaporation system can be accurately measured.
In addition, the method ensures that the vacuum degree of the position of the evaporation pipeline close to the engine reaches the vacuum degree of the intake manifold when the engine idles, so that the maximum noise state of the fuel evaporation system can be simulated, and the noise characteristic analyzed has higher reference value.
Specifically, prior to step S1, the connection between the head end of the evaporator circuit and the engine may be disconnected to connect the vacuum source to the head end of the evaporator circuit, and so configured, to facilitate connection of the vacuum source to the evaporator circuit. When the whole vehicle leaves the factory, the head end of the evaporation pipeline is connected with the engine. Of course, a test hole may be formed near the head end of the evaporation line, and a vacuum source may be connected to the test hole.
Specifically, in step S3, the opening and closing period of the solenoid valve is consistent with the opening and closing period of the solenoid valve during the actual operation of the fuel evaporation system, and when the vacuum degree of the evaporation pipeline close to the engine reaches the vacuum degree of the intake manifold when the engine is idling, the solenoid valve is opened.
More specifically, in step S3, the periodic opening and closing of the solenoid valve may be controlled by outputting a PWM signal to the solenoid valve.
Specifically, in step S4, the noise characteristics include a noise frequency and a noise frequency band.
Specifically, during testing, the fuel evaporation system may not be installed on the whole vehicle or may be detached from the whole vehicle, that is, the fuel evaporation system does not have any connection relationship with the whole vehicle (including the engine). The noise of the fuel evaporation system can thus be tested during the early development phase of the vehicle.
Specifically, during testing, the fuel evaporation system can also be arranged on the whole vehicle. In the later-stage sample vehicle evaluation stage of the vehicle, the noise of the fuel evaporation system can be tested in such a way, so that the influence of the noise of the fuel evaporation system on the NVH performance of the whole vehicle can be known. It should be noted that when the evaporator is installed on the whole vehicle, the head end of the evaporation pipeline can still be disconnected from the engine, and in the testing process, the engine still needs to be kept in a non-working state.
Referring to fig. 3, fig. 3 is a schematic diagram illustrating a use state of a noise test bed according to the present invention.
The noise test stand comprises a vacuum source 1 which is connected to a position, close to an engine, of an evaporation pipeline of a fuel evaporation system and used for enabling the vacuum degree of the position, close to the engine, of the evaporation pipeline to reach the vacuum degree of an air inlet manifold when the engine idles.
Specifically, the vacuum source 1 may be a vacuum pump, or may be a vacuum generator.
Specifically, the vacuum source 1 can be wrapped with a sound insulation layer to prevent the working noise of the vacuum source 1 from affecting the accuracy of the noise test of the fuel evaporation system.
In particular, the vacuum source 1 may be connected at the head end of the evaporation line.
More specifically, this noise test platform frame can also include a plurality of adapter tube 3, and the first end of adapter tube 3 links to each other with vacuum source 1, and the second end links to each other with the head end of evaporation pipe way. The specifications of the first ends of the adapter tubes 3 are consistent, and the specifications of the second ends of the adapter tubes 3 are different, so that the vacuum source 1 can be connected with fuel evaporation systems of different vehicle types, and the universality of the noise test bench is improved. The connected mode of adapter tube 3 and evaporation pipeline depends on the inherent structure of evaporation pipeline head end, if the head end of evaporation pipeline sets up the screw thread, then both threaded connection, if the head end of evaporation pipeline sets up the flange, then both flanges are trained the level. The adapter tube 3 can be connected with the vacuum source 1 in a flange connection mode or a threaded connection mode.
The noise test stand also comprises a control unit 2 used for controlling the solenoid valve of the fuel evaporation system to open and close periodically.
Specifically, the control unit 2 includes a PWM signal transmitting unit for transmitting a PWM signal to the solenoid valve.
The noise test stand also comprises a working table 4 for supporting the solenoid valve of the fuel evaporation system. The modal frequency of the workbench 4 is larger than 1000Hz, so that the noise influence of the workbench 4 can be avoided when the noise is tested, and the noise characteristic of the fuel evaporation system can be accurately tested and analyzed.
The noise test stand further comprises a plurality of switching supports 5, the upper ends of the switching supports 5 are fixedly connected with the electromagnetic valves of the fuel evaporation systems, and the lower ends of the switching supports 5 are fixedly connected onto the table board of the workbench 4, so that the electromagnetic valves are effectively fixed. Moreover, the specifications of the lower ends of the switching brackets 5 are consistent, and the specifications of the upper ends of the switching brackets 5 are different, so that the workbench 4 can adapt to electromagnetic valves of fuel evaporation systems of various different vehicle types, and the universality of the noise test stand is further improved.
In specific implementation, threaded holes can be formed in the table top of the workbench 4, through holes corresponding to the threaded holes one to one are formed in the lower end of each adapting support 5, and threaded fasteners penetrate through the corresponding through holes to be screwed into the corresponding threaded holes, so that the adapting supports 5 are fixedly connected to the table top of the workbench 4.
In specific implementation, threaded holes corresponding to the connection holes inherent to the electromagnetic valve in a one-to-one manner may be formed in the upper end of the adapting bracket 5, and the threaded fasteners may be screwed into the corresponding threaded holes through the corresponding connection holes.
Of course, the connection mode of the adaptor bracket 5 and the table 4 and the connection mode of the adaptor bracket 5 and the solenoid valve are not limited to the above-described screw connection, and any detachable fixed connection mode may be used.
The noise test method and the noise test bench of the fuel evaporation system provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (10)
1. A noise test method of a fuel evaporation system is characterized by comprising the following steps:
the evaporation pipeline of the fuel evaporation system is connected with a vacuum source at a position close to the engine;
starting the vacuum source to enable the vacuum degree of the position, close to the engine, of the evaporation pipeline to reach the vacuum degree of an air inlet manifold when the engine idles;
controlling the electromagnetic valve of the fuel evaporation system to open and close periodically;
noise of the fuel evaporation system is detected and noise characteristics are analyzed.
2. The noise testing method of claim 1, wherein prior to connecting the vacuum source, disconnecting the head end of the evaporation line from the engine and connecting the vacuum source to the head end of the evaporation line.
3. The noise testing method according to claim 1 or 2, wherein the fuel evaporation system is not mounted on the vehicle or has been detached from the vehicle at the time of testing.
4. The noise testing method according to claim 1 or 2, characterized in that, during testing, the fuel evaporation system is installed on the whole vehicle.
5. The noise test bench for the fuel evaporation system is characterized by comprising a vacuum source (1) connected to a position, close to an engine, of an evaporation pipeline of the fuel evaporation system, so that the vacuum degree of the position, close to the engine, of the evaporation pipeline reaches the vacuum degree of an air inlet manifold when the engine idles; the fuel evaporation system also comprises a control unit (2) for controlling the electromagnetic valve of the fuel evaporation system to open and close periodically.
6. A noise test bench according to claim 5, characterized in that the vacuum source (1) is enveloped by a sound-insulating layer.
7. The noise test bench of claim 5, wherein the vacuum source (1) is connected to the head end of the evaporation pipeline, and the head end of the evaporation pipeline is connected to the engine when the whole vehicle leaves the factory.
8. The noise test bench according to claim 7, further comprising a plurality of adapter tubes (3), a first end of the adapter tubes (3) being connected to the vacuum source (1) and a second end being connected to a head end of the evaporation line; the specifications of the first ends of the adapter tubes (3) are consistent, and the specifications of the second ends of the adapter tubes are different.
9. The noise test bench according to any of the claims 4-8, characterized in that said noise test bench further comprises a bench (4) for supporting the solenoid valves of the fuel evaporation system; the modal frequency of the workbench (4) is more than 1000 Hz.
10. The noise test bench according to claim 9, characterized in that the noise test bench further comprises a plurality of adapter brackets (5), the upper ends of the adapter brackets (5) are fixedly connected with the electromagnetic valves of the fuel evaporation system, and the lower ends of the adapter brackets are fixedly connected with the table top of the workbench (4); the specifications of the lower ends of the switching brackets (5) are consistent, and the specifications of the upper ends of the switching brackets are different.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910785657.6A CN112414722A (en) | 2019-08-23 | 2019-08-23 | Noise test method and noise test bench for fuel evaporation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910785657.6A CN112414722A (en) | 2019-08-23 | 2019-08-23 | Noise test method and noise test bench for fuel evaporation system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112414722A true CN112414722A (en) | 2021-02-26 |
Family
ID=74779018
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910785657.6A Pending CN112414722A (en) | 2019-08-23 | 2019-08-23 | Noise test method and noise test bench for fuel evaporation system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112414722A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113959708A (en) * | 2021-10-11 | 2022-01-21 | 浙江吉利控股集团有限公司 | Automobile fuel tank valve body noise test rack and valve body noise test method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1197885A (en) * | 1998-01-21 | 1998-11-04 | 干方飞 | Exhaust muffler for internal combustion engine |
| CN101198781A (en) * | 2005-06-16 | 2008-06-11 | 丰田自动车株式会社 | Starting system and method of internal combustion engine |
| CN204128677U (en) * | 2014-10-21 | 2015-01-28 | 奇瑞汽车股份有限公司 | A kind of Valve EGR noise-measuring system |
| US20170241376A1 (en) * | 2016-02-18 | 2017-08-24 | Ford Global Technologies, Llc | Evaporative emissions diagnostic during a remote start condition |
-
2019
- 2019-08-23 CN CN201910785657.6A patent/CN112414722A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1197885A (en) * | 1998-01-21 | 1998-11-04 | 干方飞 | Exhaust muffler for internal combustion engine |
| CN101198781A (en) * | 2005-06-16 | 2008-06-11 | 丰田自动车株式会社 | Starting system and method of internal combustion engine |
| CN204128677U (en) * | 2014-10-21 | 2015-01-28 | 奇瑞汽车股份有限公司 | A kind of Valve EGR noise-measuring system |
| US20170241376A1 (en) * | 2016-02-18 | 2017-08-24 | Ford Global Technologies, Llc | Evaporative emissions diagnostic during a remote start condition |
Non-Patent Citations (2)
| Title |
|---|
| 朱俊: "汽车微机控制电喷发动机的排放净化", 《汽车维修》 * |
| 郑军等: "炭罐电磁阀引起车内异响问题的分析和控制", 《汽车工程师》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113959708A (en) * | 2021-10-11 | 2022-01-21 | 浙江吉利控股集团有限公司 | Automobile fuel tank valve body noise test rack and valve body noise test method |
| CN113959708B (en) * | 2021-10-11 | 2024-03-12 | 浙江吉利控股集团有限公司 | Automobile fuel tank valve body noise test bench and valve body noise test method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107420230B (en) | Carbon tank high-load desorption pipeline desorption flow diagnosis method | |
| EP1406005B1 (en) | Method and apparatus for monitoring a controllable valve | |
| US10060394B2 (en) | Evaporative system | |
| US7383826B2 (en) | Fuel vapor treatment apparatus, system having the same, method for operating the same | |
| US6983739B2 (en) | Evaporative fuel control system for internal combustion engine | |
| US6220229B1 (en) | Apparatus for detecting evaporative emission control system leak | |
| CN110006607A (en) | A kind of system and method for EVAP Evaporative System leak detection | |
| JP2008128244A (en) | Diagnostic method of internal combustion engine | |
| US20160341141A1 (en) | Method for detecting fuel system degradation | |
| JPH06502006A (en) | Tank exhaust system and motor vehicle equipped with a tank exhaust system, as well as method and device for testing the functionality of a tank exhaust system | |
| RU2012105807A (en) | METHOD FOR PERFORMING DIAGNOSTICS OF VAPOR LEAKS FOR VEHICLES AND VEHICLES (OPTIONS) | |
| JPH0835452A (en) | Diagnostic method for evaporation purge system | |
| CN112414722A (en) | Noise test method and noise test bench for fuel evaporation system | |
| KR101602069B1 (en) | Method for diagnosing leakage of fuel tank of vehicle | |
| KR20150130244A (en) | Method for diagnosing a tank ventilation valve | |
| KR100794905B1 (en) | Leak test system of purge control solenoid valve for EVAP control system on the vehicle | |
| CN204128677U (en) | A kind of Valve EGR noise-measuring system | |
| CN113404593B (en) | Diagnosis method and device | |
| JP2010071198A (en) | Device and method for diagnosing failure of in-tank canister system | |
| JP2010071199A (en) | Device and method for diagnosing failure of in-tank canister system | |
| CN105223100A (en) | A kind of automobile canister aeration resistance pick-up unit and detection method thereof | |
| CN113223557B (en) | Knock sound optimization method for carbon tank control valve | |
| JPH06159158A (en) | Vaporized fuel leak diagnostic device of internal combustion engine | |
| CN205140365U (en) | Real standard platform of automobile engine | |
| KR100774638B1 (en) | Diagnostic apparatus of fuel supply system and diagnostic method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210226 |