Modular detection device for railway wagon brake accessories

Abstract

The invention belongs to the technical field of railway wagon brake systems, and mainly relates to a railway wagon brake accessory modular detection device. Comprising a working table, the working table is fixedly connected with a control panel, an air pump, a first tank body and a supporting unit, the first tank body is provided with a pressure sensor and an exhaust pipe provided with an electromagnetic valve, the working table is provided with a supporting frame in a sliding mode, and a first spring is installed between the supporting frame and the working table; the air outlet end of the air pump is communicated with a first air guide part through a hose, the first tank body is communicated with a second air guide part, and the first air guide part and the second air guide part are both used for being communicated with corresponding pipelines on a brake accessory module; the supporting frame is fixedly connected with a vibration unit through a fixing frame. Through the relative sliding arrangement of the workbench and the support frame and the cooperation of the vibration unit, a vibration environment is created for the brake accessory module, and the comprehensiveness and accuracy of a test result are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of railway freight car braking systems, and particularly to a modular detection device for railway freight car braking accessories. Background Art

[0002] As an important guarantee for the safe operation of trains, the reliability of the railway freight car braking system is crucial. The system includes key components such as control valves, auxiliary air cylinders, and double-chamber air cylinders. To ensure the safety and reliability of the railway freight car braking system, it is necessary to conduct various tests on it. During the existing process of detecting the sealing performance of the braking system, the airtightness of the assembled sealing system is often detected. After problems are detected, it is necessary to disassemble the specified components, increasing the operation steps of repeated assembly and disassembly, making this airtightness detection method time-consuming and laborious. At the same time, in the existing technology during the testing process, the test is often carried out when the railway freight car is in a stationary state. In fact, the components of the braking system need to withstand the influence of broadband random vibration and extreme temperature changes, which will significantly change the deformation characteristics of the seals and the structural stress distribution. The existing single test process cannot accurately reflect the performance of the braking system under the running state of the railway freight car, resulting in inaccurate test results. Summary of the Invention

[0003] In order to overcome the problems mentioned in the above background art, the present invention provides a modular detection device for railway freight car braking accessories.

[0004] The technical implementation solution of the present invention is: a modular detection device for railway freight car braking accessories, including a workbench, on which a control panel, an air pump, a first tank, and a support unit are fixedly connected. The first tank is provided with a pressure sensor and an exhaust pipe installed with a solenoid valve. A support frame for fixing the braking accessory module is slidably arranged on the workbench. A first spring is installed between the support frame and the workbench. The air outlet end of the air pump is connected to a first air guiding member through a hose. The first tank is connected to a second air guiding member. Both the first air guiding member and the second air guiding member are used to communicate with the corresponding pipes on the braking accessory module. A vibration unit is fixedly connected to the support frame through a fixing frame. The support unit is used to support the fixing frame, and the vibration unit is used to create a vibration state for the braking accessory module.

[0005] Preferably, a quick-connection unit is further included. The quick-connection unit is arranged on the first air guide member and the second air guide member. The quick-connection unit includes two fixing plates, and the two fixing plates are respectively fixedly connected to the first air guide member and the second air guide member. The first air guide member and the second air guide member are both slidably provided with sliding frames. A tension spring is fixedly connected between the sliding frame and the adjacent fixing plate. Two symmetrically distributed swing members are rotatably arranged on the sliding frame. One end of the swing member away from the adjacent sliding frame is hook-shaped, and the swing member is used to limit the corresponding pipeline in the braking fitting module.

[0006] Preferably, the first air guide member and the second air guide member are both fixedly connected with fixing rings. The fixing rings are in contact with the corresponding pipelines in the braking fitting module, and rubber convex rings are arranged on the fixing rings.

[0007] Preferably, the first air guide member and the second air guide member are both fixedly connected with elastic sleeves. The elastic sleeves are in contact with the inner walls of the corresponding pipelines in the braking fitting module.

[0008] Preferably, the elastic sleeve is provided with an annular inclined surface, and the annular inclined surface of the elastic sleeve is used to guide the gas.

[0009] Preferably, the fixing plate is fixedly connected with a limiting shell, and the limiting shell is used to limit the swing of the adjacent swing member.

[0010] Preferably, the joints between the first air guide member and the second air guide member and the adjacent elastic sleeves are step surfaces.

[0011] Preferably, it further includes: a second tank body, fixedly connected to the workbench. The second tank body is provided with a pressure sensor and an exhaust pipe for installing a solenoid valve. The second tank body is communicated with the hose through a connecting pipe; a fixing sleeve, fixedly connected inside the first air guide member. A plurality of round holes are arranged on the fixing sleeve. A sliding shell is slidably arranged on the fixing sleeve. A plurality of round holes are arranged on the sliding shell. A second spring is fixedly connected between the sliding shell and the first air guide member. When the round holes on the sliding shell are aligned with the round holes on the fixing sleeve, the inside of the first air guide member is in a communicating state.

[0012] Preferably, it further includes: a conduit, fixedly connected and communicated to the first air guide member; a sliding plug, slidably arranged on the conduit. A third spring is fixedly connected between the sliding plug and the first air guide member. The sliding plug penetrates through the first air guide member and seals and slides with it. The sliding shell is provided with a step surface. When the sliding plug contacts the step surface of the sliding shell, the sliding plug is used to limit the movement of the sliding shell.

[0013] Preferably, it further includes: a connecting frame fixedly connected to the sliding housing, the connecting frame being provided with an annular inclined surface; an elastic ring fixedly connected to the elastic sleeve connected to the first air guiding member, and the annular inclined surface of the connecting frame is used to squeeze the elastic ring.

[0014] Advantages of the present invention: Through the relative sliding arrangement of the workbench and the support frame, and in cooperation with the operation of the vibration unit, a vibration environment is created for the brake fitting module to ensure the comprehensiveness and accuracy of the test results; by using the clamping of the swinging member, the connection operation between the first air guiding member and the second air guiding member and the corresponding pipes in the brake fitting module is simplified, shortening the assembly time, thereby improving the test efficiency; through the limitation of the limiting housing, the stability of the clamping of the swinging member is ensured, that is, the firmness of the connection is improved; the sealing performance of the connection part is improved through the elastic sleeve; through the relative movement of the fixed sleeve and the sliding housing, and in cooperation with the detection of the pressure sensor in the second tank body, the detection error caused by air leakage of the detection device is eliminated; by moving the connecting frame to squeeze the elastic ring, the elastic ring squeezes the elastic sleeve to expand outward, improving the sealing performance between the elastic sleeve and the corresponding pipes in the brake fitting module. Description of the Drawings

[0015] Figure 1 is a three-dimensional structural schematic diagram of the present invention; Figure 2 is a three-dimensional structural schematic diagram of the fixed frame and the vibration unit of the present invention; Figure 3 is a three-dimensional structural schematic diagram of the hose and the first air guiding member of the present invention; Figure 4 is a cross-sectional view of the first air guiding member and the limiting housing of the present invention; Figure 5 is a cross-sectional view of the fixed sleeve and the sliding housing of the present invention; Figure 6 is a cross-sectional view of the elastic sleeve and the connecting frame of the present invention.

[0016] The labels in the figure are: 1 - workbench, 2 - control panel, 3 - support frame, 301 - first spring, 4 - air pump, 401 - hose, 5 - first air guiding member, 6 - first tank body, 601 - second air guiding member, 7 - fixed frame, 8 - vibration unit, 9 - support unit, 10 - fixing plate, 11 - sliding frame, 111 - tension spring, 12 - swinging member, 13 - fixing ring, 14 - elastic sleeve, 15 - limiting housing, 16 - second tank body, 17 - fixed sleeve, 18 - sliding housing, 19 - second spring, 20 - conduit, 21 - sliding plug, 22 - third spring, 23 - connecting frame, 24 - elastic ring. Detailed Embodiments

[0017] The present invention will be further described below with reference to the drawings and embodiments.

[0018] Embodiment 1: A modular detection device for railway freight car braking fittings, as Figures 1 - 3 shown, includes a workbench 1, on which a control panel 2, an air pump 4, a first tank 6 and a support unit 9 are fixedly connected. The control panel 2 is used to control all electrical components. The first tank 6 is provided with a pressure sensor and an exhaust pipe for installing a solenoid valve. The support unit 9 is an electric telescopic bracket. A support frame 3 for fixing the braking fitting module is slidably arranged on the workbench 1. The braking fitting module is composed of a control valve, a secondary air cylinder, a double-chamber air cylinder (or called a main air cylinder), pipelines, joints and auxiliary devices, etc. Four first springs 301 are installed between the support frame 3 and the workbench 1. The air outlet end of the air pump 4 is connected to a first air guiding member 5 through a hose 401. The first tank 6 is connected to a second air guiding member 601. Both the first air guiding member 5 and the second air guiding member 601 are used to communicate with the corresponding pipelines on the braking fitting module. The air pump 4 works to inject gas into the braking fitting module, and at the same time, in cooperation with the pressure detection of the pressure sensor in the first tank 6, the airtightness detection of the braking fitting module is completed; a vibration unit 8 is fixedly connected to the support frame 3 through a fixing frame 7. Initially, the support unit 9 is in the extended state. The support unit 9 is used to support the fixing frame 7 to keep the support frame 3 stable, facilitating the stable placement of the braking fitting module on the support frame 3. The vibration unit 8 is used to create a vibration state for the braking fitting module, and combined with the work of the air pump 4, the detection of the braking fitting module in the working state is simulated, improving the comprehensiveness of the detection results.

[0019] The working process of the modular detection device for railway freight car braking fittings in this embodiment is as follows: Preparation before detection: First, fix the braking fitting module on the support frame 3, and then connect the first air guiding member 5 and the second air guiding member 601 to the joints of the corresponding pipelines in the braking fitting module. After the braking fitting module is fixed, start the support unit 9 through the control panel 2, and the support unit 9 contracts to release the support for the fixing frame 7.

[0020] Detection process: First, start the air pump 4 through the control panel 2 to continuously inject gas into the brake fitting module. The solenoid valve on the exhaust pipe of the first tank 6 is in the closed state. During this gas injection process, open the control valve in the brake fitting module to allow the gas to flow in the brake fitting module. The flowing gas will enter the first tank 6 through the brake fitting module and the second air guide 601. The solenoid valve on the exhaust pipe of the first tank 6 is in the closed state. During the continuous gas injection process, the gas pressures in the brake fitting module and the first tank 6 gradually increase. During this process, the pressure sensor in the first tank 6 monitors the gas pressure inside it. Based on the pressure feedback of the pressure sensor on the first tank 6, judge the airtightness of the brake fitting module. During the detection process, as a specified amount of gas is injected into the brake fitting module, control the control valve in the brake fitting module to close, so that the brake fitting module maintains a certain pressure for a period of time. During this process, the pressure sensor in the first tank 6 monitors the gas pressure inside it.

[0021] During the detection process, the control panel 2 simultaneously starts the vibration unit 8. The vibration unit 8 operates to make the fixing frame 7 and the support frame 3 move up and down reciprocally. The reciprocating movement of the support frame 3 causes the brake fitting module on it to vibrate, so that the brake fitting module is detected in the working state, improving the comprehensiveness of the detection results. After the detection is completed, the operator opens the solenoid valve on the exhaust pipe of the first tank 6 to allow the gas in the brake fitting module to be discharged from the exhaust pipe of the first tank 6 through the second air guide 601. After the gas is completely discharged, disconnect the joints of the first air guide 5 and the second air guide 601 from the corresponding pipes in the brake fitting module. When detecting the remaining brake fitting modules later, just repeat the above operations.

[0022] Embodiment 2: On the basis of Embodiment 1, as Figure 1 , Figure 3 , Figure 4 and Figure 6As shown in the figure, it further includes a quick-connection unit. The quick-connection unit is arranged on the first air guide member 5 and the second air guide member 601. The quick-connection unit includes two fixing plates 10 (if there are multiple connectors in the brake fitting module, the corresponding number of air guide members and the corresponding number of fixing plates 10 are provided in this device). The two fixing plates 10 are respectively fixed to the first air guide member 5 and the second air guide member 601. A sliding frame 11 is slidably arranged on both the first air guide member 5 and the second air guide member 601. Two symmetrically distributed tension springs 111 are fixed between the sliding frame 11 and the adjacent fixing plate 10. Two symmetrically distributed swing members 12 are rotatably arranged on the sliding frame 11. One end of the swing member 12 away from the adjacent sliding frame 11 is hook-shaped. The swing member 12 is used to limit the connector on the corresponding pipeline in the brake fitting module. A limiting shell 15 is fixed to the fixing plate 10. The limiting shell 15 wraps the adjacent tension spring 111. The limiting shell 15 is used to limit the swing of the adjacent swing member 12 to ensure that the swing member 12 always contacts the connector on the corresponding pipeline in the brake fitting module. For pipelines and connectors of different specifications in the fitting module, the first air guide member 5, the second air guide member 601 and the swing member 12 are changed in corresponding dimensions. Fixed rings 13 are fixed to both the first air guide member 5 and the second air guide member 601. The fixed rings 13 are in contact with the end faces of the corresponding connectors in the brake fitting module. Rubber convex rings are arranged on the fixed rings 13 to improve the sealing effect at the corresponding connectors in the brake fitting module. Elastic sleeves 14 are fixed to both the first air guide member 5 and the second air guide member 601. The elastic sleeves 14 are in contact with the inner walls of the corresponding pipelines in the brake fitting module. After the elastic sleeves 14 are installed, they are located inside the corresponding pipelines in the brake fitting module to further improve the sealing effect at the connection between this device and the pipelines in the brake fitting module. The elastic sleeves 14 are provided with annular inclined surfaces. The annular inclined surfaces on the elastic sleeves 14 are used to guide the gas. After the elastic sleeves 14 are installed, as the gas enters the brake fitting module, the gas presses the inner walls of the elastic sleeves 14, making them closely adhere to the pipelines in the brake fitting module to prevent gas leakage from the connection. The connections between the first air guide member 5 and the second air guide member 601 and the adjacent elastic sleeves 14 are stepped surfaces to improve the sealing between the two connected components.

[0023] The working process of this embodiment continues from Embodiment 1 and is described in detail as follows: During the process of connecting this device to the corresponding pipeline in the braking fitting module, the operator holds the first air guiding member 5 with one hand, inserts the elastic sleeve 14 on the first air guiding member 5 into the corresponding pipeline. Subsequently, the operator uses the other hand to move the sliding frame 11, moving the sliding frame 11 away from the adjacent first air guiding member 5. The movement of the sliding frame 11 stretches the connected tension spring 111, and the sliding frame 11 drives the adjacent two swing members 12 to move, causing the swing members 12 to release contact with the adjacent limit shell 15. At this time, the two swing members 12 swing freely. The operator adjusts the two swing members 12 to hook the lower end of the joint on the corresponding pipeline in the braking fitting module. Subsequently, the operator releases the grip on the sliding frame 11. Under the pulling force of the tension spring 111, the sliding frame 11 and the adjacent two swing members 12 gradually retract into the adjacent limit shell 15 until the fixing ring 13 fits the end face of the joint, completing the quick connection, improving the detection efficiency. Repeating the above operations can perform the detection subsequently.

[0024] After completing the detection, the operator holds the first air guiding member 5 and pulls it, moving the first air guiding member 5 away from the corresponding pipeline in the braking fitting module. This operation causes relative movement between the sliding frame 11 and the swing member 12 and the first air guiding member 5 until the limit shell 15 releases contact with the adjacent swing member 12. Subsequently, the operator rotates the swing member 12 to release the contact between the swing member 12 and the joint in the braking fitting module. Then, the elastic sleeve 14 is pulled out of the corresponding pipeline, completing the disassembly of this testing device.

[0025] Embodiment 3: On the basis of Embodiment 2, as Figures 2 - 5 shown, it further includes: a second tank body 16, fixedly connected to the upper surface of the workbench 1. The second tank body 16 is provided with a pressure sensor and an exhaust pipe for installing an electromagnetic valve. The pressure sensor in the second tank body 16 is used to detect the connection part of this testing device, avoiding air leakage of this device from affecting the airtightness detection result of the braking fitting module, thereby eliminating detection errors. The second tank body 16 is communicated with the hose 401 through a connecting pipe; a fixing sleeve 17, fixedly connected inside the first air guiding member 5. The fixing sleeve 17 is provided with six circular holes distributed equidistantly in the circumferential direction. A sliding shell 18 is slidably arranged on the fixing sleeve 17. The sliding shell 18 is provided with six circular holes distributed equidistantly in the circumferential direction. A second spring 19 is fixedly connected between the sliding shell 18 and the first air guiding member 5. The second spring 19 is always in a compressed state. When the circular holes on the sliding shell 18 are aligned with the circular holes on the fixing sleeve 17, the inside of the first air guiding member 5 is in a communicating state.

[0026] The working process of this embodiment continues from Embodiment 2 and is described in detail as: In the initial state, the round holes on the sliding shell 18 and the round holes on the fixed sleeve 17 are staggered. After the first air guiding member 5 and the second air guiding member 601 are connected to the corresponding pipelines in the braking fitting module, an operation of injecting gas into the braking fitting module is performed. The gas flows in the hose 401 and the second tank body 16. Blocked by the sliding shell 18, the gas accumulates in the hose 401 and the second tank body 16, causing the pressure in the second tank body 16 to rise. The pressure sensor on the second tank body 16 records the pressure change. If the pressure continuously and steadily rises, it indicates that the detection device has no air leakage, ensuring the accuracy of the detection result.

[0027] During the process of the gas pressure rising, the gas squeezes the sliding shell 18 to move slowly. The sliding shell 18 moves to compress the adjacent second spring 19. After the round holes on the sliding shell 18 and the round holes on the fixed sleeve 17 are communicated, at this time, the gas enters the braking fitting module, and then the above detection operation is repeated.

[0028] Embodiment 4: On the basis of Embodiment 3, as Figure 4 and Figure 5 shown, it further includes: a conduit 20, fixedly connected and communicated with the first air guiding member 5, and both ends of the conduit 20 are located on both sides of the sliding shell 18; a sliding plug 21, slidably arranged on the conduit 20, a third spring 22 is fixedly connected between the sliding plug 21 and the first air guiding member 5, the third spring 22 is located inside the conduit 20, the sliding plug 21 penetrates through the first air guiding member 5 and seals and slides with it, the sliding shell 18 is provided with a stepped surface, when the sliding plug 21 contacts the stepped surface of the sliding shell 18, the sliding plug 21 is used to limit the movement of the sliding shell 18, and the sliding plug 21 always contacts the surface of the adjacent sliding shell 18.

[0029] The working process of this embodiment continues that of Embodiment 3 and is described in detail as follows: During the gas injection process, the gas enters the conduit 20 through the hose 401 and the first gas guide member 5. Blocked by the sliding housing 18, the air pressure in the hose 401, the first gas guide member 5, and the conduit 20 increases. The high-pressure gas in the conduit 20 presses against the sliding plug 21, causing the sliding plug 21 to always fit against the sliding housing 18. At the same time, the air pressure in the first gas guide member 5 presses the sliding housing 18 to move. When the circular hole on the sliding housing 18 communicates with the circular hole on the fixed sleeve 17, the stepped surface of the sliding housing 18 faces the sliding plug 21. Under the action of the high-pressure gas in the conduit 20, the sliding plug 21 moves to compress the third spring 22 and contacts the stepped surface of the sliding housing 18. At this time, the sliding plug 21 restricts the sliding housing 18 from resetting. Subsequently, repeat the operations in Embodiment 1 to perform airtightness detection on the brake fitting module. After the detection is completed, activate the solenoid valves on the exhaust pipes of the second tank 16 and the first tank 6 through the control panel 2 to perform a pressure relief operation on the brake fitting module. During this process, part of the gas in the brake fitting module is discharged from the exhaust pipe of the first tank 6, and the other part of the gas enters the second tank 16 through the first gas guide member 5, the circular hole on the sliding housing 18, the circular hole on the fixed sleeve 17, and the hose 401. Subsequently, the gas is discharged from the exhaust pipe of the second tank 16, enabling the gas in the brake fitting module to be discharged from both ends, evenly discharging the gas in the brake fitting module, facilitating subsequent detection of other brake fitting modules by this device, and improving the detection efficiency.

[0030] Embodiment 5: On the basis of Embodiment 4, as Figures 4 - 6 shown, it further includes: a connecting frame 23, fixedly connected to the sliding housing 18. The connecting frame 23 is composed of a connecting rod and a circular ring. The circular ring on the connecting frame 23 is provided with an annular inclined surface; an elastic ring 24, fixedly connected to the elastic sleeve 14 connected to the first gas guide member 5. The elastic ring 24 is made of rubber. An annular chamber filled with gas is provided inside the elastic ring 24. The annular inclined surface of the circular ring on the connecting frame 23 is used to squeeze the elastic ring 24.

[0031] The working process of this embodiment follows Embodiment 4 and is described in detail as follows: During the movement of the sliding housing 18, the sliding housing 18 drives the connecting frame 23 to move together. The movement of the connecting frame 23 causes the annular inclined surface of the circular ring on it to squeeze the elastic ring 24. The elastic ring 24 is compressed and expands, and the elastic ring 24 squeezes the adjacent elastic sleeve 14 to expand outward, strengthening the sealing between the elastic sleeve 14 and the adjacent pipes in the brake fitting module and preventing gas leakage from the connection.

[0032] Those skilled in the art of this industry should understand that the above embodiments do not limit the present invention in any form. Any technical solutions obtained by means of equivalent replacement or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A modular detection device for railway freight car braking fittings, characterized in that It includes a workbench (1), on which a control panel (2), an air pump (4), a first tank (6) and a support unit (9) are fixedly connected. The first tank (6) is provided with a pressure sensor and an exhaust pipe for installing a solenoid valve. A support frame (3) for fixing a brake fitting module is slidably arranged on the workbench (1). A first spring (301) is installed between the support frame (3) and the workbench (1). The air outlet end of the air pump (4) is connected to a first air guiding member (5) through a hose (401). The first tank (6) is connected to a second air guiding member (601). Both the first air guiding member (5) and the second air guiding member (601) are used for communicating with corresponding pipes on the brake fitting module; A vibration unit (8) is fixedly connected to the support frame (3) through a fixing frame (7). The support unit (9) is used for supporting the fixing frame (7). The vibration unit (8) is used for creating a vibration state for the brake fitting module.

2. The modular detection device for railway wagon braking fittings according to claim 1, characterized in that, It also includes a quick connection unit, which is arranged on the first air guiding member (5) and the second air guiding member (601). The quick connection unit includes two fixing plates (10), which are respectively fixedly connected to the first air guiding member (5) and the second air guiding member (601). Sliding frames (11) are slidably arranged on both the first air guiding member (5) and the second air guiding member (601). A tension spring (111) is fixedly connected between the sliding frame (11) and the adjacent fixing plate (10). Two symmetrically distributed swing members (12) are rotatably arranged on the sliding frame (11). One end of the swing member (12) far from the adjacent sliding frame (11) is hook-shaped. The swing member (12) is used for limiting a corresponding pipe in the brake fitting module.

3. The modular detection device for railway freight car braking fittings according to claim 2, characterized in that, Fixing rings (13) are fixedly connected to both the first air guiding member (5) and the second air guiding member (601). The fixing rings (13) are in contact with corresponding pipes in the brake fitting module. Rubber convex rings are arranged on the fixing rings (13).

4. The modular detection device for railway freight car braking accessories according to claim 3, characterized in that, Elastic sleeves (14) are fixedly connected to both the first air guiding member (5) and the second air guiding member (601). The elastic sleeves (14) are in contact with the inner walls of corresponding pipes in the brake fitting module.

5. A modular inspection device for railway wagon braking fittings according to claim 4, characterized in that, The elastic sleeve (14) is provided with an annular inclined surface, and the annular inclined surface of the elastic sleeve (14) is used for guiding gas.

6. The modular inspection device for railway wagon braking fittings according to claim 2, characterized in that, A limit shell (15) is fixedly connected to the fixing plate (10), and the limit shell (15) is used for limiting the swing of the adjacent swing member (12).

7. A modular detection device for railway freight car braking accessories according to claim 4, characterized in that, The joints of the first air guiding member (5) and the second air guiding member (601) with the adjacent elastic sleeves (14) are step surfaces.

8. A modular inspection device for railway wagon braking fittings according to claim 4, characterized in that, It also includes: A second tank (16), which is fixedly connected to the workbench (1). The second tank (16) is provided with a pressure sensor and an exhaust pipe for installing a solenoid valve. The second tank (16) is connected to the hose (401) through a connecting pipe; A fixed sleeve (17) is fixedly connected inside the first air guide member (5). A plurality of round holes are provided on the fixed sleeve (17). A sliding shell (18) is slidably arranged on the fixed sleeve (17). The sliding shell (18) is provided with a plurality of round holes. A second spring (19) is fixedly connected between the sliding shell (18) and the first air guide member (5). When the round holes on the sliding shell (18) are aligned with the round holes on the fixed sleeve (17), the inside of the first air guide member (5) is in a communicating state.

9. An inspection device for modularized railway freight car braking fittings according to claim 8, characterized in that, It further includes: A conduit (20) is fixedly connected and communicated with the first air guide member (5); A sliding plug (21) is slidably arranged on the conduit (20). A third spring (22) is fixedly connected between the sliding plug (21) and the first air guide member (5). The sliding plug (21) penetrates through the first air guide member (5) and seals and slides with it. The sliding shell (18) is provided with a stepped surface. When the sliding plug (21) contacts the stepped surface of the sliding shell (18), the sliding plug (21) is used to limit the movement of the sliding shell (18).

10. A modular inspection device for railway wagon braking fittings according to claim 9, characterized in that, It further includes: A connecting frame (23) is fixedly connected to the sliding shell (18). The connecting frame (23) is provided with an annular inclined surface; An elastic ring (24) is fixedly connected to the elastic sleeve (14) connected to the first air guide member (5). The annular inclined surface of the connecting frame (23) is used to squeeze the elastic ring (24).

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