A compact altitude simulation device for evaporative control system leak diagnosis calibration

Abstract

The application provides a small altitude simulation device for evaporation control system leakage diagnosis calibration, comprising a closed chamber, an absolute pressure sensor, a spring, a liquid sealing cavity, a magnetic force receiver, an electromagnet and a control console. The application has the beneficial effect that the sealed space is enlarged by magnetic traction to reduce the atmospheric pressure. Since gasoline is added in the fuel tank during the test of the evaporation control system, the gas volatilized from the gasoline can increase the atmospheric pressure of the sealed space, and the method has the advantage that the liquid sealing cavity is always kept in the state of the set altitude under force, so that the influence caused by the gas volatilized from the gasoline can be compensated. In addition, the arrangement of the built-in junction box can reduce the risk of pressure relief of the closed chamber caused by the arrangement of the sensor wire harness.

Description

Technical Field

[0001] This invention belongs to the field of automotive bench testing technology, and in particular relates to a small altitude simulation device for calibrating leak diagnosis in evaporation control systems. Background Technology

[0002] Appendix J of GB 18352.6-2016 "Limits and Measurement Methods for Pollutant Emissions from Light-Duty Vehicles (China VI)" (hereinafter referred to as the National VI standard) requires on-board diagnostic (OBD) systems to perform leak diagnosis of the evaporation system and meet the In Use Performance Ratio (IUPR). The requirements in the standard can be summarized as installing a fault sample with a standard small orifice in the evaporation control system, which can identify leaks and trigger an alarm; a fault-free fuel system will not trigger an alarm.

[0003] To meet regulatory and standard requirements, major OEMs, in collaboration with their suppliers, have developed various solutions. After market testing, five main solutions are now prevalent in the market, such as... Figure 2 As shown.

[0004] The above solutions are merely methods to achieve the standard requirements. In the evaporation control systems of different vehicle models, relevant parameters need to be calibrated and confirmed. Since fuel evaporation is related to altitude, temperature, and fuel quality, the current conventional method is to perform calibration during the summer calibration period (generally May to September) after the vehicle assembly is completed. This method has many drawbacks, such as the uncertainty of summer weather affecting the calibration results, the requirement that the actual vehicle be manufactured before the specified summer calibration time, and the significant impact of altitude on weather conditions. Furthermore, airtightness is also related to the manufacturing tolerances of the evaporation control system; if the evaporation control system equipped on the calibrated vehicle is not properly selected, false fault reports may occur in mass-produced models. Therefore, this application can solve the above problems. Summary of the Invention

[0005] In view of this, the present invention aims to provide a small altitude simulation device for leak diagnosis and calibration of evaporation control systems, in order to solve the problems existing in the prior art.

[0006] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0007] A small altitude simulation device for leak diagnosis and calibration of evaporation control systems includes:

[0008] A sealed chamber, the interior of which is provided to accommodate the evaporation control system and to house an absolute pressure sensor, springs, a liquid-sealed chamber, an electromagnet and a control console;

[0009] An absolute pressure sensor is installed on the top of the inner wall of the sealed chamber and is used to monitor the internal pressure of the sealed chamber.

[0010] A spring is mounted to the top of the inner wall of the sealed chamber and is used to stretch the liquid-sealed cavity.

[0011] A liquid sealing cavity is installed inside the sealed chamber, the top of the liquid sealing cavity is connected to the bottom of the spring, and the liquid sealing cavity is used to change the pressure inside the sealed chamber;

[0012] A magnetic acceptor is installed at the bottom of the liquid-sealed cavity and is used to work in conjunction with an electromagnet.

[0013] An electromagnet is installed on the bottom side of the inner wall of the sealed chamber, the electromagnet is located directly below the magnetic force receiver, the electromagnet is electrically connected to the control console, and the electromagnet is used to generate magnetic force.

[0014] The control console is installed on the bottom side of the outer wall of the sealed chamber, and the connecting wire of the electromagnet passes through the sealed chamber and is connected to the positive and negative terminals of the control console.

[0015] Furthermore, the sealed chamber includes a sealed body, a transport door, a junction box, and a support wall. The transport door is installed on one side of the sealed body, and the junction box is installed on the top of the inner wall of the sealed body. The wiring of the junction box is connected to the control console. The support wall is installed on the inner wall of the sealed body away from the transport door, and the liquid sealing cavity is installed between the support wall and the inner wall of the sealed body.

[0016] Furthermore, the liquid-sealed cavity and the supporting wall are in a sealed sliding connection.

[0017] Furthermore, the support wall is vertically disposed at the bottom of the inner wall of the sealed body.

[0018] Furthermore, the liquid-sealed cavity and the magnetic receptor are fixedly connected.

[0019] Furthermore, the liquid-sealed cavity is filled with non-volatile hydraulic oil.

[0020] Furthermore, the bottom of the sealed body is provided with several external vent holes, which are located below the electromagnet.

[0021] Furthermore, the number of external vents is at least one.

[0022] Compared with existing technologies, the small altitude simulation device for leak diagnosis and calibration of evaporation control systems described in this invention has the following advantages:

[0023] This invention discloses a small altitude simulation device for diagnosing and calibrating leaks in evaporative control systems. This device uses magnetic traction to enlarge the sealed space, thereby reducing atmospheric pressure. Since gasoline is added to the fuel tank during evaporative control system testing, the vapors from the gasoline increase the atmospheric pressure in the sealed space. The advantage of this method is that the liquid-sealed cavity is always under pressure at the set altitude, compensating for the effects of gasoline vapors. Furthermore, the built-in junction box reduces the risk of depressurization in the sealed chamber caused by sensor wiring harnesses. Attached Figure Description

[0024] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0025] Figure 1 This is a schematic diagram of the overall structure according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of a conventional evaporation control system leak diagnosis solution as described in an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1. Sealed chamber; 1.1. Transport door; 1.2. Junction box; 1.3. Support wall; 1.4. External vent; 2. Absolute pressure sensor; 3. Spring; 4. Liquid-sealed cavity; 5. Magnetic receptor; 6. Electromagnet; 7. Control console. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0030] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0031] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] like Figure 1 As shown, the technical specification of this invention provides a small altitude simulation device for leak diagnosis and calibration of an evaporation control system, comprising a sealed chamber 1, an absolute pressure sensor 2, a spring 3, a liquid-sealed cavity 4, a magnetic receptor 5, an electromagnet 6, and a control console 7. The sealed chamber 1, in addition to the main walls, also includes a transport door 1.1, a junction box 1.2, a support wall 1.3, and an external vent 1.4. The absolute pressure sensor 2 and the control console 7 are existing technologies.

[0034] At the start of the experiment, the transport door 1.1 is opened, and the evaporation control system is placed inside the sealed chamber 1. Sensor signal lines are routed on the evaporation control system, and the signals are transferred to the control console 7 via the junction box 1.2 to prevent damage to the seal. After completion, the transport door 1.1 of the sealed chamber 1 is closed, and the control console 7 locks the transport door 1.1. The magnetic receptor 5 is fixed to the liquid-sealed chamber 4, and the connection between the liquid-sealed chamber 4 and the support wall 1.3 is sealed. The liquid-sealed chamber 4 is filled with non-volatile hydraulic oil. The required altitude parameters are input into the control console 7, and the equipment is started. The control console 7 supplies power to the electromagnet 6 and gradually increases the current. The magnetic force generated by the electromagnet 6 attracts the magnetic receptor 5, causing the liquid-sealed chamber 4 to move downward. As the volume of the sealed chamber 1 increases, the pressure drops. When the absolute pressure sensor 2 monitors that the internal pressure of the sealed chamber 1 reaches the target pressure at the set altitude, the control console 7 records and maintains the current supplied to the electromagnet 6. After the experiment is completed, the control console 7 reduces the current supplied to the electromagnet 6, and the spring 3 causes the liquid-sealed chamber 4 to return to its original position. When the absolute pressure sensor 2 detects that the internal pressure of the sealed chamber 1 is close to atmospheric pressure, the transport door 1.1 is unlocked. Opening the transport door 1.1 allows the evaporation control system to be removed, and the test is completed.

[0035] Advantages of this invention:

[0036] This device uses magnetic traction to enlarge the sealed space, thereby reducing atmospheric pressure. Since gasoline is added to the fuel tank during evaporation control system testing, the vapors from the gasoline will increase the atmospheric pressure in the sealed space. The advantage of this method is that the pressure on the liquid-sealed chamber is always maintained at the set altitude, which can compensate for the effects of the gasoline vapors. Furthermore, the built-in junction box reduces the risk of depressurization in the sealed chamber caused by the placement of sensor wiring harnesses.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A small altitude simulation device for leak diagnosis and calibration of evaporation control systems, characterized in that: include: The sealed chamber (1) has an internal space for accommodating the evaporation control system and for installing the absolute pressure sensor (2), spring (3), liquid sealing chamber (4), electromagnet (6) and control console (7); An absolute pressure sensor (2) is installed on the top of the inner wall of the sealed chamber (1) and is used to monitor the internal pressure of the sealed chamber (1). Spring (3), the spring (3) is installed on the top of the inner wall of the sealed chamber (1), the spring (3) is used to stretch the liquid-sealed cavity (4); A liquid sealing cavity (4) is installed inside the sealed chamber (1). The top of the liquid sealing cavity (4) is connected to the bottom of the spring (3). The liquid sealing cavity (4) is used to change the pressure inside the sealed chamber (1). A magnetic acceptor (5) is installed at the bottom of the liquid-sealed cavity (4) and is used to work in conjunction with an electromagnet (6). An electromagnet (6) is installed on the bottom side of the inner wall of the sealed chamber (1). The electromagnet (6) is located directly below the magnetic force receiver (5). The electromagnet (6) is electrically connected to the control console (7). The electromagnet (6) is used to generate magnetic force. The control console (7) is installed on the bottom side of the outer wall of the sealed chamber (1), and the connecting wire of the electromagnet (6) passes through the sealed chamber (1) and connects to the positive and negative terminals of the control console (7); The sealed space is enlarged by using magnetic traction to reduce atmospheric pressure. Since gasoline is added to the fuel tank during the evaporation control system test, the gas emitted by the gasoline will increase the atmospheric pressure in the sealed space. Because the liquid sealed cavity is always under the force of the set altitude, it can compensate for the impact caused by the gas emitted by the gasoline.

2. The small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 1, characterized in that: The sealed chamber (1) includes a sealed body, a transport door (1.1), a junction box (1.2), and a support wall (1.3). The transport door (1.1) is installed on one side of the sealed body. The junction box (1.2) is installed on the top of the inner wall of the sealed body. The wiring of the junction box (1.2) is connected to the control console (7). The support wall (1.3) is installed on the side of the inner wall of the sealed body away from the transport door (1.1). The liquid sealing cavity (4) is installed between the support wall (1.3) and the inner wall of the sealed body.

3. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 2, characterized in that: The liquid sealing cavity (4) and the supporting wall (1.3) are in a sealed sliding connection.

4. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 2, characterized in that: The support wall (1.3) is vertically disposed at the bottom of the inner wall of the sealed body.

5. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 1, characterized in that: The liquid-sealed cavity (4) and the magnetic receptor (5) are fixedly connected.

6. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 1, characterized in that: The liquid-sealed cavity (4) is filled with non-volatile hydraulic oil.

7. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 2, characterized in that: The bottom of the sealed body is provided with several external vent holes (1.4), which are located below the electromagnet (6).

8. A small altitude simulation device for leak diagnosis and calibration of an evaporation control system according to claim 7, characterized in that: The number of external vents (1.4) is at least one.

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