A pneumatic brake anti-lock mechanism

Abstract

The present application relates to the technical field of aircraft anti-lock braking, and specifically relates to a kind of pneumatic brake anti-lock mechanism, comprising: pressure reducing valve, including upper valve block and lower valve block, connecting rod and pre-tightening spring are arranged in upper valve block, pressure reducing piston, lower valve block is equipped with pressure reducing valve air inlet and pressure reducing valve gas outlet, pressure reducing valve core and reset spring are arranged in lower valve block, pressure reducing valve core is connected with pressure reducing piston, drive connecting rod, connecting rod drives pre-tightening spring and pressure reducing piston movement towards reset spring direction, gap is generated between pressure reducing valve core and conical ring in lower valve block, gas is entered into pressure reducing valve by pressure reducing valve air inlet, the pressure exerted by gas on pressure reducing piston and the elastic force of reset spring are equal to the pressure exerted on pre-tightening spring, and gas with stable pressure is discharged by pressure reducing valve gas outlet;Realize brake anti-lock function, avoid local tire scuffing, reduce the risk of tire burst, guarantee the direction control ability, avoid the risk that aircraft deviates from runway or rushes out of runway.

Description

Technical Field

[0001] This invention relates to the field of aircraft anti-lock braking technology, specifically to a pneumatic anti-lock braking mechanism. Background Technology

[0002] An aircraft braking system is a device that slows down or stops an aircraft. Braking pressure is adjusted manually or by foot, converting the kinetic energy of the aircraft during taxiing into heat energy through friction between friction discs, which is then dissipated through natural or forced cooling. Braking pressure is usually transmitted by air or hydraulic pressure; light aircraft often use pneumatic brakes, which have the advantages of being lightweight and quick to activate.

[0003] The landing and takeoff phases are high-risk periods for flight accidents, and brake system failure or inadequate performance is one of the core contributing factors to runway deviation, tire blowouts, and other accidents. If the wheels lock up, it not only leads to localized tire abrasions and an increased risk of tire blowout, but also significantly weakens directional control, increasing the risk of veer off the runway or overrunning. Therefore, anti-lock braking technology (ABS) not only improves braking performance but also directly determines flight safety, airworthiness compliance, and operational economics during takeoff and landing. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the problem that aircraft wheel lock-up in the prior art leads to local tire abrasion, increased risk of tire blowout, significantly weakened directional control capability, and increased risk of running off the runway, thereby providing a pneumatic brake anti-lock braking mechanism.

[0005] To solve the above-mentioned technical problems, the present invention provides a pneumatic brake anti-lock braking mechanism, comprising: a pressure reducing valve, including an upper valve block and a lower valve block, wherein the upper valve block is provided with a connecting rod, a preload spring, and a pressure reducing piston; the lower valve block is provided with a pressure reducing valve inlet and a pressure reducing valve outlet, wherein the lower valve block is provided with a pressure reducing valve core and a return spring; the pressure reducing valve core is connected to the pressure reducing piston and drives the connecting rod; the connecting rod drives the preload spring and the pressure reducing piston to move toward the return spring; a gap is generated between the pressure reducing valve core and the conical ring in the lower valve block; gas enters the pressure reducing valve through the pressure reducing valve inlet; the pressure exerted by the gas on the pressure reducing piston and the elastic force of the return spring are equal to the pressure exerted on the preload spring; and gas with stable pressure is discharged from the pressure reducing valve outlet; a threshold switching valve, including a switching valve outlet and a first exhaust port, a second exhaust port, a first slide valve, a second slide valve, a first piston, and a second piston; the... The pressure reducing valve outlet is connected to the first slide valve, which is connected to the first piston via a first flow passage. The first slide valve is also connected to the second slide valve via a second flow passage, and the second slide valve is connected to the second piston via a third flow passage. The switching valve outlet is located on the main flow passage. When the first and second slide valves are in their initial positions, the first slide valve blocks the first exhaust port, and the second slide valve blocks the second exhaust port. Gas flows through the first slide valve, the main flow passage, the second flow passage, and the third flow passage, driving the second piston to move, which in turn moves the first slide valve and blocks the pressure reducing valve outlet. The first slide valve is then connected to the first exhaust port, and exhaust is emitted from the first exhaust port. Gas flows through the main flow passage and the first flow passage, driving the first piston to move, which in turn moves the second slide valve and blocks the second flow passage. The second slide valve is then connected to the second exhaust port, and exhaust is emitted from the second exhaust port.

[0006] Furthermore, the threshold switching valve also includes a first spring, a second spring, a third spring, and a fourth spring. The first spring is connected to the first slide valve, the second spring is connected to the first piston, the third spring is connected to the second slide valve, and the fourth spring is connected to the second piston. When the first slide valve moves, the pressure of the gas acting on the second piston is greater than the sum of the spring forces of the first spring and the fourth spring. When the second slide valve moves, the pressure of the gas acting on the first piston is greater than the sum of the spring forces of the second spring and the third spring.

[0007] Furthermore, the first and second slide valves are provided with valve cores, and the valve cores are provided with annular grooves, which together with the inner walls of the first and second slide valves form a receiving cavity.

[0008] Furthermore, it also includes an air intake duct, which connects the air outlet of the pressure reducing valve and the first slide valve.

[0009] Furthermore, the wall surface in contact with the conical ring of the pressure reducing valve core is conical.

[0010] Furthermore, it also includes a control lever and a support frame, the support frame being mounted on the upper valve block, and the control lever being rotatably connected to the connecting rod and the support frame.

[0011] Furthermore, the threshold switching valve also includes an upper end cover and a lower end cover, and a housing. The upper end cover and the lower end cover are located at both ends of the housing, and the first slide valve and the second slide valve are offset within the housing.

[0012] Furthermore, the first air passage portion is located inside the lower end cover, the second air passage portion is located inside the upper end cover, and the switching valve outlet, the first exhaust port, and the second exhaust port are located on the housing.

[0013] Furthermore, the housing has a first cavity and a second cavity, with the first slide valve and the second piston located in the first cavity, and the second slide valve and the first piston located in the second cavity.

[0014] Furthermore, it also includes a vent channel, through which the vent is connected to the first slide valve and the second slide valve.

[0015] The technical solution of this invention has the following advantages: 1. The pneumatic anti-lock braking mechanism provided by the present invention includes: a pressure reducing valve, comprising an upper valve block and a lower valve block, wherein the upper valve block is provided with a connecting rod, a preload spring, and a pressure reducing piston; the lower valve block is provided with a pressure reducing valve inlet and a pressure reducing valve outlet; the lower valve block is provided with a pressure reducing valve core and a return spring; the pressure reducing valve core is connected to the pressure reducing piston and drives the connecting rod; the connecting rod drives the preload spring and the pressure reducing piston to move toward the return spring; a gap is generated between the pressure reducing valve core and the conical ring in the lower valve block; gas enters the pressure reducing valve through the pressure reducing valve inlet; the pressure exerted by the gas on the pressure reducing piston and the elastic force of the return spring are equal to the pressure exerted on the preload spring; and gas with a stable pressure is discharged from the pressure reducing valve outlet; a threshold switching valve, comprising a switching valve outlet and a first exhaust port, a second exhaust port, a first slide valve, a second slide valve, a first piston, and a second piston; the pressure reducing valve outlet... The valve is connected to a first slide valve, which is connected to a first piston via a first flow passage. The first slide valve is also connected to a second slide valve via a second flow passage. The second slide valve is connected to a second piston via a third flow passage. The outlet of the switching valve is located on the main flow passage. When the first and second slide valves are in their initial positions, the first slide valve blocks the first exhaust port, and the second slide valve blocks the second exhaust port. Gas flows through the first slide valve, the main flow passage, the second flow passage, and the third flow passage, driving the second piston to move. This causes the first slide valve to move and block the outlet of the pressure reducing valve. The first slide valve is connected to the first exhaust port, and exhaust is emitted from the first exhaust port. Gas flows through the main flow passage and the first flow passage, driving the first piston to move. This causes the second slide valve to move and block the second flow passage. The second slide valve is connected to the second exhaust port, and exhaust is emitted from the second exhaust port.

[0016] This pneumatic anti-lock braking mechanism uses air pressure and the spring to generate self-excited oscillation to achieve the anti-lock braking function. When the valve core of the slide valve periodically switches the air passage, the aircraft's braking system also operates periodically, thereby achieving the anti-lock braking function, avoiding local tire abrasion, reducing the risk of tire blowout, ensuring directional control capability, and preventing the aircraft from veering off the runway or overrunning the runway.

[0017] The summary section is provided to present the chosen concepts in a simplified form, which will be further described in the detailed description below. The summary section is not intended to identify essential or necessary features of this disclosure, nor is it intended to limit the scope of this disclosure. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the pneumatic brake anti-lock braking mechanism provided by the present invention; Figure 2 A perspective view of the threshold switching valve of the pneumatic brake anti-lock braking mechanism provided by the present invention; Figure 3 A perspective view of the pressure reducing valve of the pneumatic brake anti-lock braking mechanism provided by the present invention; Figure 4 A cross-sectional view of the pneumatic brake anti-lock braking mechanism provided by the present invention; Figure 5 A schematic diagram of gas flow in the threshold switching valve of the pneumatic brake anti-lock braking mechanism provided by the present invention. Figure 6 This is a schematic diagram of the gas discharge of the threshold switching valve of the pneumatic brake anti-lock braking mechanism provided by the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Switching valve outlet; 2. Second exhaust port; 3. First exhaust port; 4. Pressure reducing valve inlet; 5. Threshold switching valve; 6. Pressure reducing valve; 7. Upper end cover; 8. First spring; 9. First slide valve; 10. Fourth spring; 11. Inlet passage; 12. Pressure reducing valve outlet; 13. Second piston; 14. Lower end cover; 15. Connecting rod; 16. First piston; 17. Second spring; 18. Vent passage; 19. Second slide valve; 20. Third spring; 21. Conical ring; 22. Return spring; 23. Lower valve block; 24. Pressure reducing valve core; 25. Pressure reducing piston; 26. Upper valve block; 27. Preload spring; 28. Control lever; 29. ​​Support frame; 30. First flow passage; 31. Second flow passage; 32. Third flow passage; 33. Main flow passage; 34. Housing; 35. First cavity; 36. Second cavity. Detailed Implementation

[0021] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this disclosure. Therefore, the drawings and description are to be considered exemplary in nature and not restrictive.

[0022] The preferred embodiments of this disclosure are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0023] Please see Figures 1 to 6 As shown, the present invention provides a pneumatic brake anti-lock braking mechanism, including a pressure reducing valve 6 and a threshold switching valve 5. The function of the pressure reducing valve 6 is to keep the gas pressure at the outlet of the pressure reducing valve stable, and then enter the threshold switching valve 5 and pass to the braking system, thereby realizing the braking function of the aircraft.

[0024] The gas in question is a high-pressure gas.

[0025] The pressure reducing valve 6 includes an upper valve block 26 and a lower valve block 23. The upper valve block 26 is provided with a connecting rod 15, a preload spring 27, and a pressure reducing piston 25. The lower valve block 23 is provided with a pressure reducing valve inlet 4 and a pressure reducing valve outlet 12. The lower valve block 23 is provided with a pressure reducing valve core 24 and a return spring 22. The pressure reducing valve core 24 is connected to the pressure reducing piston 25 and drives the connecting rod 15. The connecting rod 15 drives the preload spring 27 and the pressure reducing piston 25 to move toward the return spring 22. A gap is generated between the pressure reducing valve core 24 and the conical ring 21 in the lower valve block 23. Gas enters into the pressure reducing valve 6 through the pressure reducing valve inlet 4. The pressure of the gas applied to the pressure reducing piston 25 and the elastic force of the return spring 22 are equal to the pressure applied to the preload spring 27. Gas with stable pressure is discharged from the pressure reducing valve outlet 12. The pressure reducing valve 6 pushes the connecting rod 15 downward, thereby pushing the preload spring 27, the pressure reducing piston 25, and the pressure reducing valve core 24 downward, causing the pressure reducing valve core 24 to separate from the conical ring 21. This creates a gap between the pressure reducing valve core 24 and the conical ring 21, opening the valve port of the pressure reducing valve 6. The gas from the pressure reducing valve inlet 4 passes through the valve port and its pressure decreases. Due to the opening of the valve port, gas continuously flows into the internal cavity and various flow passages of the pressure reducing valve 6 and the threshold switching valve 5, causing the gas pressure at the pressure reducing valve outlet 12 to continuously increase. At the same time, the gas also pushes the pressure reducing piston 25 and the pressure reducing valve core 24 upward until the pressure exerted by the gas inside the pressure reducing valve 6 on the pressure reducing piston 25 and the elastic force of the return spring 22 equals the pressure exerted by the connecting rod 15 on the preload spring 27. At this point, the pressure reducing piston 25 and the pressure reducing valve core 24 are stationary, and the valve port remains open. Therefore, the gas pressure discharged from the pressure reducing valve outlet 12 of the pressure reducing valve 6 is a stable value.

[0026] The amplitude of pushing the connecting rod 15 determines the elastic deformation and spring force of the preload spring 27, and thus determines the stable value of the outlet air pressure of the pressure reducing valve 6.

[0027] The pressure reducing valve 6 is manually adjusted via the connecting rod 15 to set the pressure at the outlet 12 of the pressure reducing valve 6 to the opening pressure threshold of the braking system. The first slide valve 9 is connected to the outlet 12 of the pressure reducing valve. After the gas enters the pressure reducing valve 6 from the inlet 4 of the pressure reducing valve, it will enter the threshold switching valve 5. The pressure in the threshold switching valve 5 is adjusted to the appropriate working pressure of the braking system.

[0028] The threshold switching valve 5 includes a switching valve outlet 1, a first exhaust port 3, a second exhaust port 2, a first slide valve 9, a second slide valve 19, a first piston 16, and a second piston 13. The outlet of the pressure reducing valve 6 is connected to the first slide valve 9. The first slide valve 9 is connected to the first piston 16 through a first flow passage 30. The first slide valve 9 is connected to the second slide valve 19 through a second flow passage 31. The second slide valve 19 is connected to the second piston 13 through a third flow passage 32. The switching valve outlet 1 is located on the main flow passage 33. When the first slide valve 9 and the second slide valve 19 are in their initial positions, the first slide valve 9 blocks the... The first exhaust port 3 is blocked by the second slide valve 19. Gas drives the second piston 13 through the first slide valve 9, the main flow passage 33, the second flow passage 31, and the third flow passage 32, causing the first slide valve 9 to move and block the outlet 12 of the pressure reducing valve. The first slide valve 9 is connected to the first exhaust port 3, and the first exhaust port 3 exhausts gas. Gas drives the first piston 16 through the main flow passage 33 and the first flow passage 30, causing the second slide valve 19 to move and block the second flow passage 31. The second slide valve 19 is connected to the second exhaust port 2, and the second exhaust port 2 exhausts gas.

[0029] The threshold switching valve 5 further includes a first spring 8, a second spring 17, a third spring 20, and a fourth spring 10. The first spring 8 is connected to the first slide valve 9, the second spring 17 is connected to the first piston 16, the third spring 20 is connected to the second slide valve 19, and the fourth spring 10 is connected to the second piston 13. When the first slide valve 9 moves, the pressure of the gas acting on the second piston 13 is greater than the sum of the spring forces of the first spring 8 and the fourth spring 10; when the second slide valve 19 moves, the pressure of the gas acting on the first piston 16 is greater than the sum of the spring forces of the second spring 17 and the third spring 20.

[0030] The threshold switching valve 5 is provided with two exhaust channels, which lead to the first exhaust port 3 and the second exhaust port 2 respectively. The first exhaust passage is as follows: after the gas flows out of the pressure reducing valve outlet 12, it directly enters the first slide valve 9, the main flow passage 33, the second flow passage 31, and the third flow passage 32. The gas drives the second piston 13 to move downward, thereby causing the first slide valve 9 to descend. After the first slide valve 9 descends, it blocks the pressure reducing valve outlet 12, so that the first slide valve 9 is connected to the first exhaust port 3, and the first exhaust port 3 exhausts gas. The exhaust gas is the gas in the passage from the first piston 16 to the second slide valve 19, that is, the gas in the first flow passage 30 and the second flow passage 31; and the gas in the braking system, that is, the gas in the braking system enters the main flow passage 33, the first flow passage 30, the first slide valve 9 from the switching valve outlet 1, and then is discharged through the first exhaust port 3.

[0031] The second exhaust passage is as follows: after the gas flows out of the pressure reducing valve outlet 12, it directly enters the first slide valve 9, the main flow passage 33, and the first flow passage 30. The gas in the first flow passage 30 drives the first piston 16 to rise, which in turn moves the second slide valve 19 upward and blocks the third flow passage 32. The second slide valve 19 is connected to the second exhaust port 2, and the second exhaust port 2 exhausts gas. The exhaust gas is the gas in the passage between the second piston 13 and the second slide valve 19, that is, the gas in the third flow passage 32.

[0032] The threshold switching valve 5 uses a first slide valve 9 to switch the air passage. The first slide valve 9 and the second slide valve 19 control the opening and closing of the air passage and exhaust port inside the threshold switching valve 5 leading to the pressure reducing valve 6. When the first slide valve 9 and the second slide valve 19 are in the initial position, the threshold switching valve 5 is connected to the outlet port 12 of the pressure reducing valve, cutting off the exhaust passage, that is, cutting off the first exhaust port 3 and the second exhaust port 2, so that the gas from the pressure reducing valve 6 directly connects to the outlet port 1 of the switching valve through the first slide valve 9 and the main air passage 33, that is, to the braking system. When the first slide valve 9 and the second slide valve 19 move a certain distance until the first slide valve 9 cuts off the air passage to the pressure reducing valve 6 and the second slide valve 19 cuts off the second flow air passage 31 and opens the exhaust passage, the gas with a certain pressure in the threshold switching valve 5 will be quickly discharged from the first exhaust port 3 and the second exhaust port 2.

[0033] When the gas passes through the pressure reducing valve 6 and enters the threshold switching valve 5, it will pass through the first slide valve 9 in the initial position, the main air passage 33, and the first flow passage 30 to the switching valve outlet 1 of the braking system. At this time, the aircraft's braking system starts to work.

[0034] In addition to flowing to the outlet 1 of the switching valve in the braking system, the gas also flows through internal air passages, namely the first flow passage 30, the second flow passage 31, and the third flow passage 32, thus acting on the second piston 13 and the first piston 16. At this time, the pressure of the gas acting on the second piston 13 will be greater than the combined force of the first spring 8 and the fourth spring 10. The gas will push the second piston 13 to move, and at the same time, it will also cause the first slide valve 9 to start moving downwards until the first slide valve 9 cuts off the air passage to the pressure reducing valve 6, that is, the outlet of the pressure reducing valve 6, and connects the exhaust passage. The gas in the air passage between the first piston 16 and the second slide valve 19, as well as the gas in the braking system, is discharged from the first exhaust port 3.

[0035] At the same time, the pressure of the gas acting on the first piston 16 will be greater than the combined force of the second spring 17 and the third spring 20. The gas will push the first piston 16, and the second slide valve 19 will also begin to move upward until the second slide valve 19 closes and cuts off the second flow passage 31 and connects the second exhaust passage. The gas in the passage between the second piston 13 and the second slide valve 19 will be discharged from the second exhaust port 2.

[0036] Afterwards, the air pressure inside the threshold switching valve 5 will gradually decrease, and the aircraft's braking system will stop working. Due to the decrease in air pressure, the spring force will be greater than the pressure exerted by the gas on the first piston 16 and the second piston 13. That is, the first spring 8 and the fourth spring 10 will push the second piston 13 back to its original position, and the second spring 17 and the third spring 20 will push the first piston 16 back to its original position. Therefore, the first slide valve 9 and the second slide valve 19 will also return to their original positions, thereby cutting off the exhaust passage. The first slide valve 9 will connect the air passage to the pressure reducing valve 6. The gas from the pressure reducing valve 6 will then pass through the first slide valve 9 in its initial position, the main air passage 33, and the outlet 1 of the switching valve leading to the braking system. At this time, the aircraft's braking system will start working again.

[0037] This cycle repeats itself. When the first slide valve 9 and the second slide valve 19 periodically switch the air passages, the aircraft's braking system also operates periodically. The self-excited oscillation generated by this air pressure and the first spring 8, the second spring 17, the third spring 20 and the fourth spring 10 causes the aircraft's braking system to start and stop rapidly, thereby achieving the anti-lock braking function.

[0038] The switching frequency of the air passages can be changed, meaning the self-excited oscillation frequency generated by the air pressure and the first spring 8, second spring 17, third spring 20, and fourth spring 10 can be altered. By changing the stiffness of the first spring 8, second spring 17, third spring 20, and fourth spring 10, or the area of ​​the first piston 16 and second piston 13, the air passage switching cycle time can be changed, thus altering the air passage switching frequency. Adjustable self-excited oscillation frequency means that under different operating conditions, optimal anti-lock braking performance can be achieved by adjusting the springs and pistons.

[0039] In this embodiment, the first slide valve 9 and the second slide valve 19 are provided with valve cores, and the valve cores are provided with annular grooves. The annular grooves and the inner walls of the first slide valve 9 and the second slide valve 19 form a receiving cavity.

[0040] By providing an annular groove on the valve core, and the annular groove forming a receiving cavity with the inner wall of the slide valve, gas can enter the first flow passage 30 through the receiving cavity, providing space for gas flow.

[0041] The pneumatic brake anti-lock braking mechanism also includes an air intake 11, which connects the pressure reducing valve outlet 12 and the first slide valve 9, thereby realizing the connection between the pressure reducing valve outlet 12 and the first slide valve 9.

[0042] Specifically, the pneumatic brake anti-lock braking mechanism also includes a main air passage 33, which is connected to the first slide valve 9, the first flow passage 30, and the second flow passage 31. The outlet 1 of the switching valve is connected to the main air passage 33.

[0043] One end of the main air passage 33 is connected to the first slide valve 9, and the other end is connected to the first flow passage 30 and the second flow passage 31, forming a three-way structure within the threshold switching valve 5, thereby facilitating the smooth supply of gas.

[0044] In this embodiment, the wall surface of the pressure reducing valve core 24 that contacts the conical ring 21 is conical. This conical design facilitates a perfect fit between the pressure reducing valve core 24 and the conical ring 21, thereby ensuring the sealing of the connection between the pressure reducing valve core 24 and the conical ring 21. It also facilitates the entry of gas through the conical surface of the pressure reducing valve core 24 into the upper valve block 26, applying pressure to the pressure reducing piston 25.

[0045] The pneumatic brake anti-lock braking mechanism also includes a control lever 28 and a support frame 29. The support frame 29 is mounted on the upper valve block 26, and the control lever 28 is rotatably connected to the connecting rod 15 and the support frame 29.

[0046] The support frame 29 is mounted on the upper valve block 26, providing an installation position for the support frame 29 and ensuring its installation stability. Simultaneously, the control lever 28 is rotatably connected to the connecting rod 15 and the support frame 29. This allows the support frame 29 to serve as a fulcrum for the control lever 28 during actual use, enabling the connecting rod 15 to move. For example, to move the connecting rod 15 downwards, the control lever 28 needs to be pulled upwards.

[0047] In some optional embodiments, the threshold switching valve 5 further includes an upper end cover 7 and a lower end cover 14, and a housing 34. The upper end cover 7 and the lower end cover 14 are located at both ends of the housing 34, and the first slide valve 9 and the second slide valve 19 are misaligned within the housing 34.

[0048] The first air passage 30 is located inside the lower end cover 14, the second air passage 31 is located inside the upper end cover 7, and the switching valve outlet 1, the first exhaust port 3, and the second exhaust port 2 are located on the housing 34.

[0049] It can achieve the structural integration of the first flow air passage 30, the second flow air passage 31 with the upper end cover 7 and the lower end cover 14, avoid the structural redundancy caused by setting up additional independent air passages, make the overall layout of the threshold switching valve 5 more compact, and reduce the number of air passage connection nodes, thereby reducing the risk of media leakage.

[0050] The housing 34 includes a first cavity 35 and a second cavity 36. The first slide valve 9 and the second piston 13 are located in the first cavity 35, and the second slide valve 19 and the first piston 16 are located in the second cavity 36. The first cavity 35 provides space for the first slide valve 9 and the second piston 13, and the second cavity 36 provides space for the second slide valve 19 and the first piston 16, ensuring the stability of the installation of both the first slide valve 9 and the second piston 13, and the second slide valve 19 and the first piston 16.

[0051] The pneumatic brake anti-lock braking mechanism also includes a vent channel 18, through which the vent is connected to the first slide valve 9 and the second slide valve 19.

[0052] The vent channel 18 separates the pressure relief function from the exhaust function, improving the pressure relief efficiency. At the same time, the vent can be easily connected to an external recovery pipeline or a silencer, which not only avoids noise pollution caused by direct discharge of high-pressure media, but also enables media recycling, improving environmental protection and resource utilization.

[0053] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A pneumatic brake anti-lock braking mechanism, characterized in that, include: The pressure reducing valve (6) includes an upper valve block (26) and a lower valve block (23). The upper valve block (26) contains a connecting rod (15), a preload spring (27), and a pressure reducing piston (25). The lower valve block (23) contains a pressure reducing valve inlet (4) and a pressure reducing valve outlet (12). The lower valve block (23) contains a pressure reducing valve core (24) and a return spring (22). The pressure reducing valve core (24) is connected to the pressure reducing piston (25) and drives the connecting rod (15). The preload spring (27) and the pressure reducing piston (25) are driven to move toward the return spring (22). A gap is generated between the pressure reducing valve core (24) and the conical ring (21) in the lower valve block (23). Gas enters into the pressure reducing valve (6) through the pressure reducing valve inlet (4). The pressure of the gas on the pressure reducing piston (25) and the elastic force of the return spring (22) are equal to the pressure on the preload spring (27). Gas with stable pressure is discharged from the pressure reducing valve outlet (12). The threshold switching valve (5) includes a switching valve outlet (1), a first exhaust port (3), a second exhaust port (2), a first slide valve (9), a second slide valve (19), a first piston (16), and a second piston (13). The pressure reducing valve outlet (12) is connected to the first slide valve (9). The first slide valve (9) is connected to the first piston (16) through a first flow passage (30). The first slide valve (9) is connected to the second slide valve (19) through a second flow passage (31). The second slide valve (19) is connected to the second piston (13) through a third flow passage (32). The switching valve outlet (1) is located on the main flow passage (33). When the first slide valve (9) and the second slide valve (19) are in their initial positions, the first slide valve (9) is closed. The first exhaust port (3) is blocked, and the second slide valve (19) blocks the second exhaust port (2); the gas drives the second piston (13) to move through the first slide valve (9), the main flow passage (33), the second flow passage (31), and the third flow passage (32), which in turn moves the first slide valve (9) and blocks the outlet (12) of the pressure reducing valve. The first slide valve (9) is connected to the first exhaust port (3), and the first exhaust port (3) exhausts gas; the gas drives the first piston (16) to move through the main flow passage (33) and the first flow passage (30), which in turn moves the second slide valve (19) and blocks the second flow passage (31). The second slide valve (19) is connected to the second exhaust port (2), and the second exhaust port (2) exhausts gas.

2. The pneumatic brake anti-lock braking mechanism according to claim 1, characterized in that, The threshold switching valve (5) further includes a first spring (8), a second spring (17), a third spring (20), and a fourth spring (10). The first spring (8) is connected to the first slide valve (9), the second spring (17) is connected to the first piston (16), the third spring (20) is connected to the second slide valve (19), and the fourth spring (10) is connected to the second piston (13). When the first slide valve (9) moves, the pressure of the gas acting on the second piston (13) is greater than the sum of the spring forces of the first spring (8) and the fourth spring (10); when the second slide valve (19) moves, the pressure of the gas acting on the first piston (16) is greater than the sum of the spring forces of the second spring (17) and the third spring (20).

3. A pneumatic brake anti-lock braking mechanism according to claim 2, characterized in that, The first slide valve (9) and the second slide valve (19) are provided with valve cores, and the valve cores are provided with annular grooves. The annular grooves and the inner walls of the first slide valve (9) and the second slide valve (19) form a receiving cavity.

4. A pneumatic brake anti-lock braking mechanism according to any one of claims 1-3, characterized in that, It also includes an air intake (11) that connects the air outlet (12) of the pressure reducing valve and the first slide valve (9).

5. A pneumatic brake anti-lock braking mechanism according to claim 4, characterized in that, The wall surface in contact between the pressure reducing valve core (24) and the conical ring (21) is conical.

6. A pneumatic brake anti-lock braking mechanism according to claim 4, characterized in that, It also includes a control lever (28) and a support frame (29), the support frame (29) being mounted on the upper valve block (26), and the control lever (28) being rotatably connected to the connecting rod (15) and the support frame (29).

7. A pneumatic brake anti-lock braking mechanism according to claim 6, characterized in that, The threshold switching valve (5) also includes an upper end cover (7) and a lower end cover (14), and a housing (34). The upper end cover (7) and the lower end cover (14) are located at both ends of the housing (34), and the first slide valve (9) and the second slide valve (19) are misaligned within the housing (34).

8. A pneumatic brake anti-lock braking mechanism according to claim 7, characterized in that, The first air passage (30) is located inside the lower end cover (14), the second air passage (31) is located inside the upper end cover (7), and the switching valve outlet (1), the first exhaust port (3), and the second exhaust port (2) are located on the housing (34).

9. A pneumatic brake anti-lock braking mechanism according to claim 7, characterized in that, The housing (34) has a first cavity (35) and a second cavity (36), the first slide valve (9) and the second piston (13) are located in the first cavity (35), and the second slide valve (19) and the first piston (16) are located in the second cavity (36).

10. A pneumatic brake anti-lock braking mechanism according to claim 1, characterized in that, It also includes a vent channel (18), through which the vent is connected to the first slide valve (9) and the second slide valve (19).

Images