A leakage detection device for a fuel evaporation pipe

Abstract

The present invention relates to the technical field of airtightness detection of pipes, and specifically to a leakage detection device for a fuel evaporation pipe, which includes a detection chassis and a detection mechanism arranged inside the detection chassis. An adjustment mechanism is also arranged inside the detection chassis. The adjustment mechanism includes a group of adjustment boxes movably installed on the side wall of the detection chassis. An activity port is opened on the front surface of the adjustment box, and a carrier plate is arranged outside the activity port. A main connector is arranged at the center position of the front surface of the carrier plate and serves as a detection port for airtightness detection. By arranging a number of replacement mechanisms, according to the model of the evaporation pipe actually detected, the spare connectors in different positions of the replacement mechanism are selected to be connected to the main connector, so as to realize multi-purpose use of one machine and improve convenience. By arranging a rotation mechanism to finely adjust the main connector, the direction of the detection port of the main connector is changed, which reduces the bending and twisting degrees of the evaporation pipe when it is connected to a certain extent and avoids affecting the finished product quality of the evaporation pipe.

Description

Technical Field

[0001] The present invention relates to the technical field of airtightness detection of pipes, and specifically to a leakage detection device for a fuel evaporation pipe. Background Art

[0002] Automobile fuel tanks are usually filled with gasoline vapor. By setting up a fuel evaporation control system, on the one hand, it is to balance the air pressure in the fuel tank and introduce the gasoline vapor into the engine for combustion through an evaporation pipe; on the other hand, it is to prevent the gasoline vapor from being discharged into the atmosphere and causing pollution. The gasoline vapor is introduced into an activated carbon canister through the evaporation pipe to adsorb the gasoline molecules in the vapor. Thus, it can be seen that the evaporation pipe is used as an indispensable connecting pipe in the fuel evaporation control system.

[0003] To ensure the normal operation of the fuel system and determine whether there is a leakage in the evaporation pipe, the manufacturer will conduct an airtightness test on the finished evaporation pipe. The air inspection method is a commonly used airtightness detection method for pipeline systems. During the detection, one end of the pipe is sealed, nitrogen is injected along the other end of the pipe, and a leak detection instrument is used to evaluate the airtight performance of the pipe. This method can detect tiny gas leaks and has the advantages of high detection accuracy and high automation.

[0004] A patent application with the application number CN202110727599.9 discloses an airtightness inspection device for automobile pipelines. The specification mentions that currently, many enterprises use manual operations such as tightening the joints at both ends by hand or clamping with a large pliers during the airtightness detection of automobile pipelines. These operations are cumbersome, the detection efficiency is low, and the labor intensity of employees is high, resulting in fewer finished products produced every day. In the current airtightness inspection device for automobile pipelines, when detecting the airtightness of automobile pipelines, problems such as improper fixation and failed airtightness detection often occur, and the sealing performance of the automobile pipeline cannot be guaranteed. After being installed on the automobile, there are certain potential safety hazards.

[0005] In addition to the problems mentioned in the above patent, the airtightness detection devices in the prior art also have the following defects: In order to facilitate the connection to the fuel evaporation control system in a specific space, the evaporation pipe generally consists of a rubber pipe body and a metal pipe head. There is a common phenomenon of bending of the metal pipe head. Its overall shape is generally divided into straight pipes, bent pipes, single-sided elbows or double-sided elbows, etc. For these evaporation pipes with different specifications, the existing detection devices generally adopt the solution of setting multiple sets of detection joints with different specifications on the same detection device, or setting multiple independent detection devices. Therefore, when detecting evaporation pipes with different specifications, it is necessary to frequently replace the detection port groups adapted to them, which will increase the maintenance components and maintenance frequency of the device. Moreover, these detection joints are usually fixed on the detection device, and during the detection, it is necessary to continuously move the evaporation pipe to cooperate with the connection of the joint. This continuous adjustment process of the finished evaporation pipe, such as bending and twisting, is likely to affect the quality of the finished product. Summary of the Invention

[0006] To achieve the above object, the present invention provides the following technical solution: A leakage detection device for a fuel evaporation pipe, including a detection chassis and a detection mechanism arranged inside the detection chassis. The detection mechanism uses the air detection method to detect the airtight performance. An adjustment mechanism is also arranged inside the detection chassis. The adjustment mechanism includes a group of adjustment boxes movably installed on the side wall of the detection chassis. An activity port is opened on the front surface of the adjustment box, and a carrier plate is arranged outside the activity port. A main joint is arranged at the center position of the front surface of the carrier plate, serving as the detection port for airtightness detection;

[0007] A fixed plate is fixedly arranged inside the adjustment box. A first groove is opened at the center position of the fixed plate. The inner edge of the first groove is in a rack-like structure. A number of push-pull rods for connecting the carrier plate are movably arranged on the fixed plate. A rotation mechanism is arranged inside the first groove, used to adjust the positional relationship between the carrier plate and the adjustment box;

[0008] A number of replacement mechanisms distributed outside the edge of the carrier plate are arranged on the front surface of the adjustment box. The replacement mechanism includes a bottom plate installed on the adjustment box. A cylinder I is installed on the bottom plate. One end of the starting rod of the cylinder I is movably connected with a cantilever, and a fixed frame is also fixedly installed on the cylinder I, serving as the fixed fulcrum of the cantilever. A spare joint is installed at one end of the cantilever. The spare joint is connected with the main joint to change the type of the detection port.

[0009] Preferably, a placement table is arranged on the workbench of the detection chassis. Two card seats are movably arranged on the placement table. An evaporation pipe is clamped on the two card seats. Both ends of the evaporation pipe are respectively connected to the main joints of the two adjustment mechanisms.

[0010] Preferably, the detection mechanism mainly includes a nitrogen tank installed on the detection chassis, a delivery pump for delivering nitrogen, and a nitrogen leak detector arranged in the workbench area of the detection chassis. The output end of the nitrogen tank is connected to the input end of the delivery pump. One end of the output end of the delivery pump is connected with a first conduit.

[0011] Preferably, one end of the first conduit is connected with a second conduit. The second conduit movably penetrates into the cavity of the adjustment box and is connected to the carrier plate. The second conduit, the carrier plate and the main joint are internally connected.

[0012] Preferably, the diameter of the carrier plate is smaller than the diameter of the activity port. A number of notches for the movement of the push-pull rods are opened at the edge of the activity port. A number of through holes are also opened on the front surface of the adjustment box, used for installing the replacement mechanism through bolts.

[0013] Preferably, a plurality of second grooves are formed on the outer surface of the fixed disk, and a slider is slidably connected in each second groove. One end of the push rod is movably connected to the slider, and the other end of the push rod is movably connected to the carrier disk. A spring is fixedly connected between one side surface of the slider and one inner wall of the second groove.

[0014] Preferably, the rotating mechanism includes a driving shaft, a connecting plate fixedly connected to the driving shaft, a gear rotatably connected to the other end of the connecting plate, and a second cylinder rotatably mounted on the top of the gear.

[0015] Preferably, the driving shaft is rotatably connected to the center of the first groove through a rotating shaft, and the gear meshes with the internal rack of the first groove.

[0016] Preferably, a circular sliding groove is formed on the end surface of the carrier disk opposite to the main joint, and one end of the pneumatic rod of the second cylinder is slidably connected to the inside of the circular sliding groove.

[0017] Preferably, a motor is arranged in the detection chassis in the area close to the adjustment box. The output shaft of the motor respectively passes through the detection chassis, the adjustment box, and the fixed disk movably and is fixedly connected to the rotating shaft of the driving shaft. Advantageous Effects

[0018] Compared with the prior art, the present invention provides a leakage detection device for a fuel evaporation pipe, which has the following advantageous effects:

[0019] By arranging an adjustment mechanism in the workbench area of the detection chassis, the main joint in the adjustment mechanism is used as a fixed detection port for airtightness detection. A plurality of replacement mechanisms are arranged around the main joint. The type of the actual detected evaporation pipe is determined, and then a spare joint in a different replacement mechanism is selected to be connected to the main joint, so as to achieve the effect of changing a variety of different spare joints at the same detection port. This method realizes multi-purpose use of one machine, improves convenience, and is also convenient for the maintenance of the detection mechanism and the entire detection device;

[0020] When the evaporation pipe is placed on the workbench for detection, first, the main joint is finely adjusted through the rotating mechanism according to the port direction of the evaporation pipe, so as to change the detection port direction of the main joint, which brings convenience for the main joint to adapt to connect to the port of the evaporation pipe. This way of making the main joint actively cooperate with the evaporation pipe for connection reduces the bending and twisting degrees of the evaporation pipe when it is connected to a certain extent, and avoids affecting the finished product quality of the evaporation pipe. Description of the Drawings

[0021] The drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The illustrative embodiments and descriptions thereof of the present application are used to explain the present application and do not constitute an improper limitation to the present application. In the drawings:

[0022] Figure 1 This is the overall structure diagram of the detection chassis and adjustment mechanism of the present invention;

[0023] Figure 2 This is the structural schematic diagram of the adjustment mechanism of the present invention;

[0024] Figure 3 This is the front view of the detection chassis and adjustment mechanism of the present invention;

[0025] Figure 4 This is the present invention Figure 3 The enlarged view of part A in;

[0026] Figure 5 This is the exploded view of the adjustment box and its internal structure of the adjustment mechanism of the present invention;

[0027] Figure 6 This is the structural schematic diagram of the rotating mechanism arranged in the carrier plate of the present invention;

[0028] Figure 7 This is the structural schematic diagram of the replacement mechanism arranged outside the adjustment box of the present invention.

[0029] Explanation of reference numerals:

[0030] Detection chassis; 11, Placement table; 12, Card seat; 13, Evaporation tube; 14, First conduit;

[0031] Adjustment box; 21, Movable opening; 22, Fixed plate; 221, First groove; 222, Second groove; 223, Push-pull rod; 224, Spring;

[0032] Carrier plate; 31, Main joint; 32, Second conduit;

[0033] Replacement mechanism; 41, Base plate; 42, Cylinder 1; 43, Cantilever; 44, Fixed bracket; 45, Spare joint;

[0034] 5, Driving shaft; 51, Connecting plate; 52, Gear; 53, Cylinder 2. Specific implementation mode

[0035] The following will cooperate with the drawings and embodiments to detail the implementation mode of the present application, so as to fully understand how the present application uses technical means to solve technical problems and achieve the implementation process of technical effects and implement accordingly.

[0036] Embodiment 1, as Figures 1-7As shown in the figure, to achieve the above object, the present invention provides the following technical solution: A leakage detection device for a fuel evaporation pipe, comprising a detection chassis 1 and a detection mechanism arranged in the detection chassis 1. The detection mechanism uses the air detection method to detect the airtight performance. An adjustment mechanism is also arranged in the detection chassis 1. The adjustment mechanism includes a group of adjustment boxes 2 movably installed on the side wall of the detection chassis 1. An activity port 21 is opened on the front surface of the adjustment box 2, and a carrier plate 3 is arranged outside the activity port 21. A main joint 31 is arranged at the center position of the front surface of the carrier plate 3, serving as a detection port for airtight detection;

[0037] Among them, the detection mechanism mainly includes a nitrogen tank installed on the detection chassis 1, a delivery pump for delivering nitrogen, and a nitrogen leak detector arranged in the workbench area of the detection chassis 1. The output end of the nitrogen tank is connected to the input end of the delivery pump. One end of the output end of the delivery pump is connected with a first conduit 14. One end of the first conduit 14 is connected with a second conduit 32. The second conduit 32 movably penetrates into the cavity of the adjustment box 2 and is connected to the carrier plate 3. The second conduit 32, the carrier plate 3 and the main joint 31 are internally connected. During detection, the nitrogen in the nitrogen tank is delivered to the detection port of the main joint 31 along the first conduit 14 and the second conduit 32 by starting the delivery pump;

[0038] Furthermore, a placement table 11 is arranged on the workbench of the detection chassis 1. Two clamping seats 12 are movably arranged on the placement table 11. An evaporation pipe 13 is clamped on the two clamping seats 12. Both ends of the evaporation pipe 13 are respectively connected to the main joints 31 of the two adjustment mechanisms. During detection, nitrogen is injected into the evaporation pipe 13 along the main joint 31, and then the nitrogen leak detector is used to detect whether there is a leakage phenomenon in the evaporation pipe 13. If there is a leakage phenomenon, it is considered that the evaporation pipe 13 is an unqualified finished product. If there is no leakage phenomenon, it is considered that the evaporation pipe 13 is a qualified finished product.

[0039] Embodiment 2, as Figures 2-6 shown, a fixed disk 22 is fixedly arranged inside the adjustment box 2. A first groove 221 is opened at the center position of the fixed disk 22. The inner edge of the first groove 221 is in a rack-like structure. A number of push-pull rods 223 for connecting the carrier plate 3 are movably arranged on the fixed disk 22. The diameter of the carrier plate 3 is smaller than the diameter of the activity port 21, so that when the carrier plate 3 rotates around its center point, it will not touch the edge of the activity port 21. A number of notches for the movement of the push-pull rods 223 are opened on the edge of the activity port 21, so that the push-pull rods 223 have enough movement space when they move. A number of through holes are also opened on the front surface of the adjustment box 2 for installing the replacement mechanism 4 by bolts. The installation quantity of the replacement mechanism 4 can be increased or decreased according to actual needs, and the installation position of the replacement mechanism 4 can be changed according to actual convenience;

[0040] Further, a plurality of second grooves 222 are formed on the outer surface of the fixed disk 22. A slider is slidably connected in each second groove 222. One end of the push rod 223 is movably connected to the slider, and the other end of the push rod 223 is movably connected to the carrier disk 3. A spring 224 is fixedly connected between one side surface of the slider and one inner wall of the second groove 222. When one end of the push rod 223 moves in the second groove 222, the other end of the push rod 223 drives the carrier disk 3 to deflect, thereby changing the detection port orientation of the main joint 31, facilitating the connection of the main joint 31 to the port of the evaporation pipe 13. This way of actively matching the main joint 31 to connect with the evaporation pipe 13 reduces the bending and twisting degrees of the evaporation pipe 13 when it is connected to a certain extent, avoiding affecting the finished product quality of the evaporation pipe 13.

[0041] Embodiment 3, as Figure 5 and Figure 6 shown, a rotating mechanism is arranged in the first groove 221 for adjusting the positional relationship between the carrier disk 3 and the adjustment box 2. The rotating mechanism includes a driving shaft 5, a connecting plate 51 fixedly connected to the driving shaft 5, a gear 52 rotatably connected to the other end of the connecting plate 51, and a second cylinder 53 rotatably mounted on the top of the gear 52. The driving shaft 5 is rotatably connected to the center position of the first groove 221 through a rotating shaft. The gear 52 meshes with the inner wall rack of the first groove 221. When the driving shaft 5 rotates, the gear 52 is driven to move synchronously through the connecting plate 51. The gear 52 revolves around the center of the driving shaft 5 and rotates itself at the same time. The second cylinder 53 is rotatably connected to the gear 52. Therefore, during the revolution of the gear 52, the second cylinder 53 is driven to move synchronously. The change in the position of the second cylinder 53 is convenient for driving and controlling different edge positions on the carrier disk 3. And the self-rotation of the gear 52 does not drive the second cylinder 53 to rotate synchronously. The meshing of the second cylinder 53 with the inner wall rack of the first groove 221 can increase the stability of the entire rotating mechanism;

[0042] Among them, a circular sliding groove is formed on the end face of the carrier disk 3 opposite to the main joint 31. One end of the pneumatic rod of the second cylinder 53 is slidably connected to the inside of the circular sliding groove. A motor is arranged in the detection chassis 1 in the area close to the adjustment box 2. The output shaft of the motor respectively movably penetrates the detection chassis 1, the adjustment box 2, and the fixed disk 22 and is fixedly connected to the rotating shaft of the driving shaft 5. The driving shaft 5 is driven to rotate by the motor, thereby driving the above-mentioned gear 52 and the second cylinder 53 to move or rotate. The second cylinder 53 drives its pneumatic rod to extend and retract. When the pneumatic rod extends and retracts, the carrier disk 3 is driven to deflect, thereby changing the detection port direction of the main joint 31.

[0043] Embodiment 4, as Figure 2 and Figure 7As shown in the figure, a number of replacement mechanisms 4 are arranged on the front surface of the adjustment box 2, which are distributed outside the edge of the carrier plate 3. The replacement mechanism 4 includes a bottom plate 41 installed on the adjustment box 2. A cylinder 42 is installed on the bottom plate 41. One end of the starting rod of the cylinder 42 is movably connected to a cantilever 43. A fixed frame 44 is also fixedly installed on the cylinder 42, which serves as a fixed fulcrum for the cantilever 43. A spare joint 45 is installed at one end of the cantilever 43. In the initial state, that is, when the evaporation pipe 13 is not detected, the pneumatic rod of the cylinder 42 contracts inside it. At this time, one end of the cantilever 43 drives the spare joint 45 to be the farthest from the main joint 31, and will not block the access of the evaporation pipe 13.

[0044] Among them, the spare joint 45 is connected to the main joint 31 to change the type of the detection port. Since the cantilever 43 is movably connected to one end of the pneumatic rod of the cylinder 42, after the spare joint 45 is connected to the main joint 31, the spare joint 45 will not inhibit the main joint 31 when the main joint 31 is slightly adjusted. According to the type of the evaporation pipe 13 actually detected, the spare joint 45 in the replacement mechanism 4 at different positions is selected to be connected to the main joint 31, so as to achieve the effect of changing a variety of different spare joints 45 at the same detection port. This method is convenient for the maintenance of the detection mechanism and the whole detection device, and has high convenience.

[0045] When the above-mentioned embodiment works, when the evaporation pipe 13 is connected, first place the evaporation pipe 13 in the card seat 12, and connect the two ends of the evaporation pipe 13 to the main joints 31 of the two adjustment mechanisms respectively. Before the port of the evaporation pipe 13 is connected to the main joint 31, first start the motor to drive the driving shaft 5 to rotate, and then drive the above-mentioned gear 52 and cylinder 53 to move or rotate. At the same time, start the cylinder 53 to drive its pneumatic rod to extend and retract. When the pneumatic rod extends and retracts, it drives the carrier plate 3 to deflect, and then changes the detection port direction of the main joint 31, which brings convenience to the main joint 31 to adapt to connect the port of the evaporation pipe 13. This way of making the main joint 31 actively cooperate with the evaporation pipe 13 for connection reduces the bending and torsion degree of the evaporation pipe 13 when it is connected to a certain extent, and avoids affecting the finished product quality of the evaporation pipe 13.

[0046] During detection, start the transfer pump to transport the nitrogen in the nitrogen tank along the first conduit 14 and the second conduit 32 to the detection port of the main joint 31. The nitrogen is injected into the evaporation pipe 13 along the main joint 31, and then use a nitrogen leak detector to detect whether there is a leakage phenomenon in the evaporation pipe 13. If there is a leakage phenomenon, it is considered that the evaporation pipe 13 is an unqualified finished product. If there is no leakage phenomenon, it is considered that the evaporation pipe 13 is a qualified finished product.

[0047] When replacing the model of the evaporation tube 13 to be detected, start the first cylinder 42 so that its pneumatic rod drives the cantilever 43 to deflect. As a result, the cantilever 43 drives the spare connector 45 to change from the initial state of being away from the main connector 31 to being connected to the main connector 31. According to the actually detected model of the evaporation tube 13, select the spare connector 45 in the different-position adjustment mechanism 4 to be connected to the main connector 31, so as to achieve the effect of changing multiple different spare connectors 45 at the same detection port. This way realizes multi-purpose use of one machine, improves convenience, and is also convenient for the maintenance of the detection mechanism and the entire detection device.

[0048] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A leakage detection device for a fuel evaporation pipe, comprising a detection chassis (1) and a detection mechanism arranged inside the detection chassis (1), wherein the detection mechanism uses the air detection method to detect the airtight performance, and is characterized in that: An adjustment mechanism is further provided inside the detection chassis (1). The adjustment mechanism includes a set of adjustment boxes (2) movably installed on the side wall of the detection chassis (1). An activity port (21) is opened on the front surface of the adjustment box (2), and a carrier plate (3) is arranged outside the activity port (21). A main joint (31) is arranged at the center position of the front surface of the carrier plate (3), which serves as a detection port for airtightness detection. A fixed plate (22) is fixedly arranged inside the adjustment box (2). A first groove (221) is opened at the center position of the fixed plate (22). The inner edge of the first groove (221) is in a rack-like structure. A number of push-pull rods (223) for connecting the carrier plate (3) are movably arranged on the fixed plate (22). A rotating mechanism is arranged in the first groove (221) for adjusting the positional relationship between the carrier plate (3) and the adjustment box (2). A number of replacement mechanisms (4) are arranged on the front surface of the adjustment box (2) and distributed outside the edge of the carrier plate (3). The replacement mechanism (4) includes a bottom plate (41) installed on the adjustment box (2). A cylinder one (42) is installed on the bottom plate (41). One end of the starting rod of the cylinder one (42) is movably connected to a cantilever (43). A fixed frame (44) is also fixedly installed on the cylinder one (42), which serves as a fixed fulcrum for the cantilever (43). A spare joint (45) is installed at one end of the cantilever (43). The spare joint (45) is connected to the main joint (31) to change the type of the detection port. The rotating mechanism includes a driving shaft (5), a connecting plate (51) fixedly connected to the driving shaft (5), a gear (52) rotatably connected to the other end of the connecting plate (51), and a cylinder two (53) rotatably installed on the top of the gear (52). The driving shaft (5) is rotatably connected to the center position of the first groove (221) through a rotating shaft. The gear (52) meshes with the inner wall rack of the first groove (221). A circular sliding groove is opened on the end face of the carrier plate (3) opposite to the main joint (31). One end of the pneumatic rod of the cylinder two (53) is slidably connected inside the circular sliding groove. A motor is arranged in the area of the detection chassis (1) close to the adjustment box (2). The output shaft of the motor respectively movably penetrates through the detection chassis (1), the adjustment box (2), the fixed plate (22) and is fixedly connected to the rotating shaft of the driving shaft (5).

2. The leak detection device for a fuel evaporation pipe according to claim 1, wherein: A placement table (11) is arranged on the workbench of the detection chassis (1). Two clamping seats (12) are movably arranged on the placement table (11). An evaporation pipe (13) is clamped on the two clamping seats (12). Both ends of the evaporation pipe (13) are respectively connected to the main joints (31) of the two adjustment mechanisms.

3. The leakage detection device for a fuel evaporation pipe according to claim 1, characterized in that: The detection mechanism mainly includes a nitrogen tank installed on the detection chassis (1), a delivery pump for delivering nitrogen, and a nitrogen leak detector arranged in the workbench area of the detection chassis (1). The output end of the nitrogen tank is connected to the input end of the delivery pump. One end of the output end of the delivery pump is connected to a first conduit (14).

4. A leakage detection device for a fuel evaporation pipe according to claim 3, characterized in that: One end of the first conduit (14) is connected to a second conduit (32). The second conduit (32) movably penetrates into the cavity of the adjustment box (2) and is connected to the carrier plate (3). The second conduit (32), the carrier plate (3) and the main joint (31) are internally communicated.

5. The leakage detection device for a fuel evaporation pipe according to claim 1, characterized in that: The diameter of the carrier plate (3) is smaller than the diameter of the movable opening (21). A plurality of notches for the movement of the push-pull rod (223) are formed at the edge of the movable opening (21). A plurality of through holes are further formed on the front surface of the adjustment box (2) for installing the replacement mechanism (4) by bolts.

6. The leakage detection device for a fuel evaporation pipe according to claim 1, characterized in that: A plurality of second grooves (222) are formed on the outer surface of the fixed plate (22). A slider is slidably connected in each second groove (222). One end of the push-pull rod (223) is movably connected to the slider, and the other end of the push-pull rod (223) is movably connected to the carrier plate (3). A spring (224) is fixedly connected between one side surface of the slider and one inner wall of the second groove (222).

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