Active pressure regulation system and method for unbalanced load on truck front axle

Abstract

The present invention discloses an active pressure regulation system and method for load imbalance on a truck's front axle, belonging to the fields of mechanical devices and transportation technology. The system comprises a three-position, six-way valve, which includes a front axle balance detection mechanism and a pressure-regulating actuator for controlling the pressure in the oil-pneumatic suspension chambers on the left and right sides of the front axle. The front axle balance detection mechanism automatically detects whether the front axle is in a balanced state. The front axle balance detection mechanism then controls the pressure-regulating actuator to adjust the pressure in the oil-pneumatic suspension chambers on the left and right sides of the front axle, ultimately balancing the axle and preventing the construction vehicle from rolling. The system features a simple structure, high reliability, and rapid response, enabling rapid adjustment of the truck's front axle balance.

Description

Technical Field

[0001] The invention relates to a system and method for actively regulating pressure due to unbalanced load on a front axle of a truck, and belongs to the technical field of mechanical devices and transportation. Background Art

[0002] Hydro-pneumatic suspensions have excellent nonlinear stiffness and damping properties and are commonly used in heavy-duty construction vehicles, providing excellent vibration damping under both empty and fully loaded conditions. Based on the location of the suspension chamber, hydro-pneumatic suspensions can be divided into integrated hydro-pneumatic and separated hydro-pneumatic suspensions. The former has its chamber located within the suspension cylinder, consisting of both an air and oil chamber. This type of hydro-pneumatic suspension is compact and has a weaker load-bearing capacity, making it primarily used on the front axles of construction vehicles. The latter requires an external accumulator connected to the hydraulic cylinder, with the gas in the accumulator serving as the elastic medium. This type of suspension occupies a large installation space but offers a higher load-bearing capacity, making it primarily used on the rear or center-rear axles of construction vehicles. Currently, some heavy-duty construction vehicles experience load imbalance in the front suspension. This results in inconsistent piston rod extension and contraction in the hydro-pneumatic cylinders on both sides of the front axle, leading to inconsistent gas pressures in the cylinder chambers on both sides, posing a significant threat to driver and passenger safety. Summary of the Invention

[0003] In response to the above-mentioned technical deficiencies, the present invention provides a system and method for active pressure regulation of unbalanced load on the front axle of a truck. By automatically detecting whether the front axle is in a balanced state, the system inflates the low-pressure air chamber and deflates the high-pressure air chamber, so that the axle is finally in a balanced state, preventing the truck from tipping over.

[0004] To solve the above technical problems, the present invention provides an active pressure regulation system for front axle load imbalance, comprising a three-position six-way valve, which includes a front axle balance detection mechanism and a pressure regulating actuator for controlling the pressure of the oil-gas suspension chambers on the left and right sides of the front axle. The front axle balance detection mechanism automatically detects whether the front axle is in a balanced state, and then the front axle balance detection mechanism controls the pressure regulating actuator to adjust the pressure of the oil-gas suspension chambers on the left and right sides of the front axle, so that the axle is ultimately in a balanced state, thereby preventing the engineering vehicle from tilting.

[0005] The front axle balance detection mechanism includes a housing and a matching housing cover, under which a swing rod is suspended via a hanging ear and a bolt a, which swings naturally left and right according to the center;

[0006] The pressure regulating actuator includes an upper shell and a lower shell that match each other. A three-position six-way valve cavity is provided between the upper shell and the lower shell. A slide valve with a three-position six-way valve core structure is provided in the three-position six-way valve cavity. Springs are provided on both sides of the slide valve. Two sealing side plates are installed on both sides of the upper shell and the lower shell by bolts b. A sealing bottom plate is provided under the lower shell. The upper shell, the lower shell and the bottom plate are matched and fixed by multiple bolts c and nuts a. The upper shell is located on the left and right sides of the rocker arm and is respectively provided with two channels horizontally. The tails of the two channels are respectively connected to the three-position six-way valve cavity where the slide valve is located. The two ends are connected, and a left nozzle is provided at the end of the left channel corresponding to the rocker arm, and a right nozzle is provided at the end of the right channel corresponding to the rocker arm. The left nozzle is connected to the left end cavity of the slide valve, and the right nozzle is connected to the right end cavity of the slide valve. When the rocker arm is in the middle position, the liquid pressure on both sides of the slide valve connected to the left nozzle and the right nozzle is the same, and overflows to the oil return cylinder. When the rocker arm tilts to the left, the left nozzle will be blocked by the rocker arm. Since the tail end of the connecting channel of the left nozzle is connected to the left end of the slide valve, the oil pressure of the left nozzle becomes larger, pushing the slide valve to the right and moving the slide valve to the right side of the three-position six-way valve cavity, and vice versa.

[0007] The three-position six-way valve is located in the middle of the pressure regulating actuator and is provided with an oil return port T. Oil inlets P are provided on the left and right sides of the oil return port T respectively. Oil ports B1 and B2 of the control oil circuit are provided between the oil return port T and the left oil inlet P. Oil ports A1 and A2 of the control oil circuit are provided between the oil return port T and the right oil inlet P. The oil return port T is connected to the oil return cylinder, and the oil inlet P is connected to the hydraulic cylinder through the oil pump. The oil inlet P is also connected to the oil return cylinder through the overflow valve. When the slide valve moves to the right, the oil in the P port on the right end will enter the oil ports A1 and A2; if the slide valve moves to the left, the oil in the P port on the left end will flow into the oil ports A1 and A2. The oil will enter the oil ports B1 and B2; the upper housing is also provided with two oil return holes C1 and C2 connected to the cavity of the three-position six-way valve. The oil return hole C2 is connected to the oil ports A1 and A2 for oil return from the oil ports A1 and A2, and the oil return hole C1 is connected to the oil ports B1 and B2 for oil return from the oil ports B1 and B2. When the slide valve is in the middle position of the cavity of the three-position six-way valve, both oil return holes are connected. When the slide valve is on the left side of the cavity of the three-position six-way valve, the oil return hole connected to the cavity where the oil ports B1 and B2 are located is closed by the slide valve, and the oil return hole connected to the cavity where the oil ports A1 and A2 are located is connected, and vice versa.

[0008] The A1 port pipeline of the three-position six-way valve is connected to the first-stage oil cylinder a through the two-position three-way valve b. The first-stage oil cylinder a is provided with a second-stage oil cylinder a. The piston rod end of the first-stage oil cylinder a is provided with an air valve a controlled by it. The air valve a is respectively connected to the air source and the left suspension cylinder. The air valve a is successively connected to the hydraulic control check valve a and the air control check valve a through the left suspension cylinder; the B1 port pipeline is connected to the first-stage oil cylinder through the two-position three-way valve a. The first-stage oil cylinder is provided with a second-stage oil cylinder b. The piston rod end of the first-stage oil cylinder b is provided with an air valve b controlled by it. The air valve b is respectively It is connected to the air source and the right suspension cylinder, and the air valve b is connected to the hydraulically controlled one-way valve b and the air-controlled one-way valve b in sequence through the right suspension cylinder; the left suspension cylinder is also connected to the controlled air-controlled one-way valve b through a pipeline, and the right suspension cylinder is also connected to the controlled air-controlled one-way valve a through a pipeline. When the vehicle deviates to the left and the left suspension cylinder is still overloaded after being inflated to the maximum value, the air-controlled one-way valve b is controlled to deflate the right suspension cylinder, thereby completing the overload adjustment; the A2 port is also connected to the controlled hydraulically controlled one-way valve b through a pipeline; the B2 port is also connected to the controlled hydraulically controlled one-way valve a through a pipeline.

[0009] Furthermore, the first-stage oil cylinder includes a cylinder body a, a piston rod a is provided in the cylinder body a, a cylinder cover a is installed on the cylinder body a through a bolt d, and a spring a is sleeved on the piston rod a in the rod cavity; wherein the end of the piston rod a is provided with an air valve core a and is arranged in the air valve, and the air valve a includes a dual-channel valve body a, and the dual-channel valve body a is connected and fixed by a bolt a and a nut b, and the movement of the piston rod a controls the movement of the air valve core a in the dual-channel valve body a, thereby controlling the opening and closing of the valve body channel.

[0010] Furthermore, the first-stage oil cylinder includes a cylinder body b, a piston rod b is provided in the cylinder body b, a cylinder cover b is installed on the cylinder body b by a bolt e, and a spring b is sleeved on the piston rod b in the rod cavity; wherein the end of the piston rod b is provided with an air valve core b and is arranged in the air valve, and the air valve b includes a dual-channel valve body b, and the dual-channel valve body b is connected and fixed by a bolt b and a nut c, and the movement of the piston rod b controls the movement of the air valve core b in the dual-channel valve body b, thereby controlling the opening and closing of the valve body channel.

[0011] Furthermore, the stiffness of spring a and spring b is not less than 3.1 times the spring stiffness of secondary oil cylinder a and secondary oil cylinder b.

[0012] Furthermore, when the rocker arm in the three-position, six-way valve is in the middle position, the pressures at both ends of the slide valve are the same, and the slide valve does not move. This is the middle position. Since the rocker arm is kept vertical due to the influence of gravity, when the three-position, six-way valve tilts with the vehicle body, resulting in the left side being lower and the right side being higher, the gap between the left nozzle and the rocker arm decreases. Since the outflow of the left nozzle is blocked by the rocker arm, the oil pressure at the left end of the slide valve is greater than that at the right end, and the slide valve moves to the right. This is the right position. Conversely, the gap between the right nozzle and the rocker arm decreases, indicating the left position.

[0013] When the three-position six-way valve is in the middle position, the left nozzle and the right nozzle are inactive, the oil inlet at port P can return to the cylinder, and the four oil ports A1, A2, B1, and B2 are all connected to the return cylinder; when the slide valve of the three-position six-way valve is in the left position, the left oil inlet P is connected to the two left oil ports B1 and B2, and the oil return port T is not connected to the two left oil ports B1 and B2; when the slide valve of the three-position six-way valve is in the right position, the right oil inlet P is connected to the two right oil ports A1 and A2, and the oil return port T is not connected to the two right oil ports A1 and A2.

[0014] A method for adjusting a pressure active regulation system for a front axle load imbalance comprises the following steps: using a rocker arm to actively detect whether the front axle of a truck is overloaded; if the left side is overloaded, the rocker arm swings to the left and blocks the left nozzle, causing the other end to overflow back into the oil cylinder, with more overflow than when in the neutral position. At this time, the pressure on the left side increases, while the pressure on the right side decreases; when the slide valve moves to the left, the oil return hole C1 on the left is blocked; when the slide valve moves to the right, the oil return hole C2 on the right is blocked; when the slide valve does not move in the neutral position, it is inoperative, and the oil return holes C1 and C2 on both sides are not blocked;

[0015] The slide valve moves to the right side of the three-position six-way valve cavity. At this time, the three-position six-way valve is in the right position, the right control oil circuit is open, and the oil ports A1 and A2 are working. The oil in the first-stage cylinder b overflows directly back to the cylinder (4) through the two-position three-way valve a, and the oil ports B1 and B2 correspond to the oil return hole C1, and the oil ports A1 and A2 correspond to the oil return hole C2. During this process, the oil port A1 is connected to the cylinder, and the oil port A2 serves as the hydraulic control port. When the slide valve moves to the left, the oil enters the oil circuit from the oil ports B1 and B2, and the oil return hole C1 on the left is blocked by the slide valve, and the oil will not flow back to the cylinder. Similarly, when the slide valve moves to the right, the oil return hole C1 on the left and the oil ports B1 and B2 correspond to return oil. When the slide valve is in the middle position, the two oil return holes C1 and C2 return oil at the same time.

[0016] The oil port A1 on the right side of the three-position six-way valve controls the opening of the two-position three-way valve b and enters the right chamber of the first-stage oil cylinder a and the second-stage oil cylinder a connected thereto through the two-position three-way valve b. Since the stiffness of spring a is much greater than that of the second-stage oil cylinder a, the oil first fills the second-stage oil cylinder a and then the right chamber of the first-stage oil cylinder a. When the oil fills the right chamber of the first-stage oil cylinder a, the oil overcomes spring a and moves to the left, causing the valve core a of the air valve a to move to the left, allowing the air source to communicate with the air chamber of the left suspension cylinder for inflation;

[0017] The right oil port A2 of the three-position six-way valve controls the hydraulically controlled one-way valve b to open, and the air chamber of the left suspension cylinder is connected to the air control port of the air-controlled one-way valve b. When the gas pressure in the left air chamber of the left suspension cylinder reaches the set maximum pressure value, the air-controlled one-way valve b is reversed and leads to the atmosphere, realizing the deflation of the right air chamber of the right suspension cylinder;

[0018] If the right side is overloaded, the rocker arm swings to the right and blocks the right nozzle. At this time, when the pressure on the left side decreases and the pressure on the right side increases, the slide valve moves, the three-position six-way valve is in the left position, the left control oil circuit is open, the oil ports B1 and B2 are in operation, and the oil in the cylinder overflows directly back to the cylinder through the two-position three-way valve b, and the oil returns to the oil ports A1 and A2;

[0019] The oil port B1 on the left side of the three-position six-way valve controls the opening of the two-position three-way valve a and enters the left chamber of the first-stage oil cylinder b and the second-stage oil cylinder b connected to it through the two-position three-way valve a. Since the stiffness of spring b is much greater than that of the second-stage oil cylinder b, the oil first fills the second-stage oil cylinder b, and then fills the left chamber of the first-stage oil cylinder b. When the oil fills the left chamber of the first-stage oil cylinder b, the oil overcomes the limit spring and moves to the right, causing the valve core of the air valve b to move to the right, so that the air source is connected to the air chamber of the right suspension cylinder, realizing inflation;

[0020] The oil port B2 on the left side of the three-position six-way valve controls the hydraulically controlled one-way valve a to open, and the air chamber of the right suspension cylinder 20 is connected to the air control port of the air-controlled one-way valve a. When the gas pressure in the right air chamber of the right suspension cylinder reaches the set maximum pressure value, the air-controlled one-way valve a is reversed and leads to the atmosphere, thereby realizing the deflation of the left air chamber of the left suspension cylinder. Beneficial effects

[0021] The three-position, six-way valve employed in this invention utilizes a mechanical mechanism to detect axle overload. If the vehicle's front overhang is biased to the left, the sway bar in the detection mechanism will also be biased to the left, and vice versa. This device offers high stability, fast response, and strong reliability, enabling active inflation and deflation of the suspension cylinder chamber, preventing overinflation that can cause the axle to remain unbalanced even after inflation on one side. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the active pressure regulation system for front axle load imbalance in an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of the structure of the eccentric load detection mechanism in an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of the actuator in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of the first-stage oil cylinder a and the air valve in an embodiment of the present invention;

[0026] Figure 5 Schematic diagram of the structure of the first-stage oil cylinder b and the air valve in an embodiment of the present invention.

[0027] In the figure: 1- hydraulic cylinder, 2- oil pump, 3- overflow valve, 4- oil return cylinder, 5- three-position six-way valve, 6- two-position three-way valve a, 7- two-position three-way valve b, 8- first-stage oil cylinder a, 9- first-stage oil cylinder b, 10- second-stage oil cylinder a, 11- second-stage oil cylinder b1, 12- air valve a, 13- air valve b, 14- air source, 15- hydraulically controlled one-way valve a, 16- hydraulically controlled one-way valve b, 17- air-controlled one-way valve a, 18- air-controlled one-way valve b, 19- left suspension cylinder, 20- right suspension cylinder, 21- eccentric load detection mechanism, 22- actuator, 23- housing, 24- housing cover 2, 25- lifting ear, 26- rocker arm, 27- gasket, 2 8-bolt a, 29-upper housing, 30-lower housing, 31-bottom plate, 32-side plate, 33-left nozzle, 34-right nozzle, 35-slide valve, 36-spring c, 37-bolt b, 38-bolt c, 39-nut a, 40-plug rod a, 41-spring a, 42-cylinder body a, 43-cylinder head a, 44-bolt d, 45-plug rod b, 46-spring b, 47-cylinder body b, 48-cylinder head b, 49-bolt e, 50-dual-channel valve body a, 51-air valve core a, 52-bolt e, 53-nut b, 54-dual-channel valve body b, 55-valve core b, 56-bolt f, 57-nut c. DETAILED DESCRIPTION

[0028] The embodiments of the present invention are further described below with reference to the accompanying drawings:

[0029] like Figure 1 The figure shows an active pressure regulation system for unbalanced load on the front axle of a truck, including a three-position six-way valve, a two-position three-way valve, a first-stage oil cylinder, a second-stage oil cylinder, an air valve, a hydraulically controlled one-way valve, and an air-controlled one-way valve. The oil-air suspension section includes a left suspension cylinder and a right suspension cylinder. To reduce installation space and simplify installation methods, some control valves are combined with the main mechanical part. The implementation points are as follows:

[0030] like Figure 2 and Figure 3 As shown, the three-position six-way valve 5 includes: an eccentric load detection mechanism 21 and an actuator 22, which are welded together. The eccentric load detection mechanism 21 includes a housing 23, a housing cover 24, a lifting lug 25, a rocker 26, a washer 27, and a bolt a28. The actuator 22 includes an upper housing 29, a lower housing 30, a bottom plate 31, a side plate 32, a nozzle 33, a nozzle 34, a slide valve 35, a spring c36, a bolt b37, a bolt c38, and a nut a39.

[0031] The A1 port pipeline of the three-position six-way valve 5 is connected to the first-stage oil cylinder a8 through the two-position three-way valve b7. The first-stage oil cylinder a8 is provided with a second-stage oil cylinder a10. The end of the piston rod of the first-stage oil cylinder a8 is provided with a gas valve a12 controlled by it. The gas valve a12 is respectively connected to the air source 14 and the left suspension cylinder 19. The gas valve a12 is connected to the hydraulic control check valve a15 and the gas control check valve a17 in sequence through the left suspension cylinder 19; the B1 port pipeline is connected to the first-stage oil cylinder 9 through the two-position three-way valve a6. The first-stage oil cylinder 9 is provided with a second-stage oil cylinder b11. The end of the piston rod of the first-stage oil cylinder b9 is provided with a gas valve b13 controlled by it. The gas valve b13 They are respectively connected to the air source 14 and the right suspension cylinder 20, and the air valve b13 is connected to the hydraulically controlled one-way valve b16 and the air-controlled one-way valve b18 in sequence through the right suspension cylinder 20; the left suspension cylinder 19 is also connected to the controlled air-controlled one-way valve b18 through a pipeline, and the right suspension cylinder 20 is also connected to the controlled air-controlled one-way valve a17 through a pipeline. When the vehicle deviates to the left and the left suspension cylinder 19 is inflated to the maximum value but is still overloaded, the air-controlled one-way valve b18 is controlled to deflate the right suspension cylinder 20, thereby completing the overload adjustment; the A2 port is also connected to the controlled hydraulically controlled one-way valve b16 through a pipeline; the B2 port is also connected to the controlled hydraulically controlled one-way valve a15 through a pipeline.

[0032] The first-stage oil cylinder 8 includes: a piston rod 40, a spring 41, a cylinder body 42, a cylinder cover 43, and a bolt 44. The stiffness of the spring 41 is much greater than the spring stiffness of the second-stage oil cylinder 10. The first-stage oil cylinder 9 includes a piston rod 45, a spring b46, a cylinder body 47, a cylinder cover 48, and a bolt 49. The stiffness of the spring b46 is much greater than the spring stiffness of the second-stage oil cylinder 11.

[0033] The air valve a12 includes: a valve body a50, a valve core a51, a bolt e52, and a nut b53. The valve core a51 and the piston rod a40 are welded together. Figure 4 As shown;

[0034] The air valve b13 includes: a valve body b54, a valve core b55, a bolt f56, and a nut c57. The valve core b55 and the piston rod b45 are welded together. Figure 5 As shown;

[0035] The two-position three-way valve a6 and the two-position three-way valve b7 are hydraulically controlled two-position three-way valves.

[0036] A method for actively regulating pressure of unbalanced load on a truck front axle, specifically comprising:

[0037] When the vehicle load is balanced, the rocker arm 26 does not move and the system does not work;

[0038] If the left side is overloaded, the rocker arm 26 swings to the left to block the left nozzle 33. At this time, the three-position six-way valve 5 is in the right position, and the right control oil circuit is open to oil. The control oil port A1 on the right side of the three-position six-way valve 5 controls the two-position three-way valve b7 to open and enters the right chamber of the first-stage oil cylinder 8 and the second-stage oil cylinder 10 connected thereto through the two-position three-way valve b7. Since the stiffness of the spring 41 is much greater than the spring stiffness of the second-stage oil cylinder 10, the oil first fills the second-stage oil cylinder 10 and then fills the right chamber of the first-stage oil cylinder 8. When the oil fills the right chamber of the first-stage oil cylinder 8, the oil overcomes the spring 41 and moves to the left, causing the valve core 51 of the air valve a12 to move to the left, so that the air source 14 is connected to the air chamber of the left suspension cylinder 19 to achieve inflation; the control oil port A2 on the right side of the three-position six-way valve 5 controls the hydraulically controlled one-way valve 16 to open, and the air chamber of the left suspension cylinder 19 is connected to the air control port of the air-controlled one-way valve 18. When the gas pressure in the left air chamber reaches the set maximum pressure value, the air-controlled one-way valve 18 is reversed and leads to the atmosphere, thereby achieving deflation of the right air chamber;

[0039] If the right side is overloaded, the rocker arm 26 swings to the right to block the right nozzle. At this time, the three-position six-way valve 5 is in the left position, and the left control oil circuit is open to oil. When the oil pressure in the left cylinder is too low, the oil in the left cylinder 1 is opened, and the air in the right cylinder 20 is opened, so that the air in the left cylinder 1 is opened and the air in the right cylinder 2 is opened.

Claims

1. A pressure active regulation system for front axle load imbalance, characterized by: The three-position six-way valve (5) includes a front axle balance detection mechanism (21) and a pressure regulating actuator (22) for controlling the pressure of the oil-gas suspension air chambers on the left and right sides of the front axle. The front axle balance detection mechanism (21) automatically detects whether the front axle is in a balanced state, and then the front axle balance detection mechanism (21) controls the pressure regulating actuator (22) to adjust the pressure of the oil-gas suspension air chambers on the left and right sides of the front axle, so that the axle is finally in a balanced state, thereby preventing the engineering vehicle from tilting. The front axle balance detection mechanism (21) includes a housing (23) and a matching housing cover (24), and a swing rod (26) is suspended below the housing cover (24) via a hanging ear (25) and a bolt a (28) so as to swing naturally left and right according to the center. The pressure regulating actuator (22) comprises an upper shell (29) and a lower shell (30) that match each other. A three-position six-way valve cavity is provided between the upper shell (29) and the lower shell (30). A slide valve (35) with a three-position six-way valve core structure is provided in the three-position six-way valve cavity. Springs c (36) are provided on both sides of the slide valve (35). Two sealing side plates (32) are installed on both sides of the upper shell (29) and the lower shell (30) by bolts b (37). A sealing bottom plate (31) is provided below the lower shell (30). The upper shell (29), the lower shell (30) and the bottom plate (31) are matched and fixed by multiple bolts c (38) and nuts a (39). Two channels are provided horizontally on the left and right sides of the upper shell (29) located on the rocker rod (26). The tail ends of the two channels are respectively connected to the three-position position of the slide valve (35). The six-way valve cavity is connected at both ends, and a left nozzle (33) is provided at the end of the left channel corresponding to the rocker rod (26), and a right nozzle (34) is provided at the end of the right channel corresponding to the rocker rod (26). The left nozzle (33) is connected to the left end cavity of the slide valve (35), and the right nozzle (34) is connected to the right end cavity of the slide valve (35); when the rocker rod (26) is in the middle position, the liquid pressure on both sides of the slide valve (35) connected to the left nozzle (33) and the right nozzle (34) is the same, and overflows to the oil return cylinder. When the rocker rod (26) tilts to the left, the left nozzle (33) will be blocked by the rocker rod (26). Since the tail of the connecting channel of the left nozzle (33) is connected to the left end of the slide valve (35), the oil pressure of the left nozzle (33) increases, pushing the slide valve (35) to the right, so that the slide valve (35) moves to the right side of the three-position six-way valve cavity, and vice versa. The three-position six-way valve (5) is located in the middle of the pressure regulating actuator (22) and is provided with an oil return port T. Oil inlets P are provided on the left and right sides of the oil return port T. Oil ports B1 and B2 for controlling the oil circuit are provided between the oil return port T and the left oil inlet P. Oil ports A1 and A2 for controlling the oil circuit are provided between the oil return port T and the right oil inlet P. The oil return port T is connected to the oil return cylinder (4). The oil inlet P is connected to the hydraulic cylinder (1) through the oil pump (2). The oil inlet P is also connected to the oil return cylinder (4) through the overflow valve (3). When the slide valve (35) moves to the right, the oil in the P port on the right side will enter the oil ports A1 and A2. If the slide valve (35) moves to the left, the oil in the P port on the right side will enter the oil ports A1 and A2. , the oil at the left end of the P port will enter the oil ports B1 and B2; the upper housing (29) is also provided with two oil return holes C1 and C2 connected to the three-position six-way valve cavity, the oil return hole C2 is connected to the oil ports A1 and A2 for oil return from the oil ports A1 and A2, and the oil return hole C1 is connected to the oil ports B1 and B2 for oil return from the oil ports B1 and B2. When the slide valve (35) is located in the middle position of the three-position six-way valve cavity, both oil return holes are connected. When the slide valve (35) is located on the left side of the three-position six-way valve cavity, the oil return hole connected to the cavity where the oil ports B1 and B2 are located is closed by the slide valve (35), and the oil return hole connected to the cavity where the oil ports A1 and A2 are located is connected, and vice versa. The A1 port pipeline of the three-position six-way valve (5) is connected to the first-stage oil cylinder a (8) through the two-position three-way valve b (7). The first-stage oil cylinder a (8) is provided with a second-stage oil cylinder a (10). The piston rod end of the first-stage oil cylinder a (8) is provided with an air valve a (12). The air valve a (12) is respectively connected to the air source (14) and the left suspension cylinder (19). The air valve a (12) is connected to the hydraulic control check valve a (15) and the air control check valve a (17) in sequence through the left suspension cylinder (19). The B1 port pipeline is connected to the first-stage oil cylinder b (9) through the two-position three-way valve a (6). The first-stage oil cylinder b (9) is provided with a second-stage oil cylinder b (11). The piston rod end of the first-stage oil cylinder b (9) is provided with an air valve b (13). The air valve b (1 3) are connected to the air source (14) and the right suspension cylinder (20), respectively. The air valve b (13) is connected to the hydraulic control check valve b (16) and the air control check valve b (18) in sequence through the right suspension cylinder (20); the left suspension cylinder (19) is also connected to the control air control check valve b (18) through a pipeline, and the right suspension cylinder (20) is also connected to the control air control check valve a (17) through a pipeline. When the vehicle deviates to the left and the left suspension cylinder (19) is inflated to the maximum value but still has an unbalanced load, the air control check valve b (18) is controlled to deflate the right suspension cylinder (20), thereby completing the unbalanced load adjustment; the A2 port is also connected to the control hydraulic control check valve b (16) through a pipeline; the B2 port is also connected to the control hydraulic control check valve a (15) through a pipeline.

2. The active pressure regulation system for front axle load imbalance according to claim 1, characterized in that: The first-stage oil cylinder a (8) includes a cylinder body a (42), a piston rod a (40) is provided in the cylinder body a (42), a cylinder cover a (43) is installed on the cylinder body a (42) through a bolt d (44), and a spring a (41) is provided on the piston rod a (40) in a rod cavity; wherein an air valve core a (51) is provided at the end of the piston rod a (40) and is arranged in the air valve a (12), and the air valve a (12) includes a dual-channel valve body a (50), and the dual-channel valve body a (50) is connected and fixed by a bolt f (52) and a nut b (53), and the movement of the piston rod a (40) controls the movement of the air valve core a (51) in the dual-channel valve body a (50), thereby controlling the opening and closing of the valve body channel.

3. The active pressure regulation system for front axle load imbalance according to claim 1, characterized in that: The first-stage oil cylinder b (9) includes a cylinder body b (47), a piston rod b (45) is provided in the cylinder body b (47), a cylinder cover b (48) is installed on the cylinder body b (47) through a bolt e (49), and a spring b (46) is provided on the piston rod b (45) in the rod cavity; wherein the end of the piston rod b (45) is provided with a gas valve core b (55) and is arranged in the gas valve a (12), and the gas valve b (13) includes a dual-channel valve body b (54), and the dual-channel valve body b (54) is connected and fixed by a bolt g ​​(56) and a nut c (57), and the movement of the piston rod b (45) controls the movement of the gas valve core b (55) in the dual-channel valve body b (54), thereby controlling the opening and closing of the valve body channel.

4. The active pressure regulation system for front axle load imbalance according to claim 1, characterized in that: The stiffness of spring a (41) and spring b (46) is not less than 3.1 times the spring stiffness of secondary oil cylinder a (10) and secondary oil cylinder b (11).

5. The active pressure regulation system for front axle load imbalance according to claim 1, characterized in that: When the rocker (26) in the three-position six-way valve (5) is in the middle position, the pressure at both ends of the slide valve (35) is the same, and the slide valve (35) does not move. At this time, it is the middle position; because the rocker (26) is kept vertical under the influence of gravity, when the three-position six-way valve (5) tilts with the vehicle body, resulting in the left side being lower and the right side being higher, the gap between the left nozzle (33) and the rocker (26) decreases. Since the outflow of the left nozzle (33) is blocked by the rocker (26), the oil pressure at the left end of the slide valve (35) is greater than that at the right end, and the slide valve (35) moves to the right. At this time, it is the right position; on the contrary, the gap between the right nozzle (34) and the rocker (26) decreases, and it is the left position. When the three-position six-way valve (5) is in the middle position, the left nozzle (33) and the right nozzle (34) are inactive, the oil inlet at the P port can return to the oil cylinder (4), and the four oil ports A1, A2, B1, and B2 are all connected to the oil return cylinder (4); when the slide valve (35) of the three-position six-way valve (5) is in the left position, the left oil inlet P is connected to the two left oil ports B1 and B2, and the oil return port T is not connected to the two left oil ports B1 and B2; when the slide valve (35) of the three-position six-way valve (5) is in the right position, the right oil inlet P is connected to the two right oil ports A1 and A2, and the oil return port T is not connected to the two right oil ports A1 and A2.

6. A method for adjusting the pressure active adjustment system for the front axle load imbalance according to any one of claims 1 to 5, characterized in that step: The swing arm (26) is used to actively detect whether the front axle of the truck is overloaded. If the left side is overloaded, the swing arm (26) swings to the left and blocks the left nozzle (33). The other end overflows back to the oil cylinder (4) and the overflow is greater than when it is in the middle position. At this time, the pressure on the left side becomes larger and the pressure on the right side becomes smaller. When the slide valve (35) moves to the left, the oil return hole C1 on the left is blocked; when the slide valve (35) moves to the right, the oil return hole C2 on the right is blocked. The slide valve (35) does not move in the middle position and is not working. The oil return holes C1 and C2 on both sides are not blocked. The slide valve (35) moves to the right side of the three-position six-way valve cavity. At this time, the three-position six-way valve (5) is in the right position, the right control oil circuit is open, the oil ports A1 and A2 are working, and the oil in the first-stage cylinder b (9) directly overflows back to the cylinder (4) through the two-position three-way valve a (6). The oil ports B1 and B2 return oil to the corresponding return oil hole C1, and the oil ports A1 and A2 return oil to the corresponding return oil hole C2. During this process, the oil port A1 is connected to the first-stage cylinder a (8), and the oil port A2 serves as the hydraulic control port. When the slide valve (35) moves to the left, the oil enters the oil circuit from the oil ports B1 and B2. The return oil hole C1 on the left is blocked by the slide valve (35), and the oil does not flow back to the return cylinder (4). Similarly, when the slide valve (35) moves to the right, the oil return hole C1 on the left side and the oil ports B1 and B2 return oil. When the slide valve (35) is in the middle position, the two return oil holes C1 and C2 return oil at the same time. The oil port A1 on the right side of the three-position six-way valve (5) controls the two-position three-way valve b (7) to open and enters the right chamber of the first-stage oil cylinder a (8) and the second-stage oil cylinder a (10) connected thereto through the two-position three-way valve b (7). Since the stiffness of the spring a (41) is much greater than the spring stiffness of the second-stage oil cylinder a (10), the oil first fills the second-stage oil cylinder a (10) and then fills the right chamber of the first-stage oil cylinder a (8). When the oil fills the right chamber of the first-stage oil cylinder a (8), the oil overcomes the spring a (41) and moves to the left, causing the valve core a (51) of the air valve a (12) to move to the left, so that the air source (14) is connected to the air chamber of the left suspension cylinder (19) for inflation; The right oil port A2 of the three-position six-way valve (5) controls the hydraulic control check valve b (16) to open, and the air chamber of the left suspension cylinder (19) is connected to the air control port of the air control check valve b (18). When the gas pressure in the left air chamber of the left suspension cylinder (19) reaches the set maximum pressure value, the air control check valve b (18) is reversed and opened to the atmosphere, thereby achieving the degassing of the right air chamber of the right suspension cylinder (20); If the right side is overloaded, the rocker arm (26) swings to the right and blocks the right nozzle (34). At this time, the pressure on the left side decreases and the pressure on the right side increases. The slide valve (35) moves, and the three-position six-way valve (5) is in the left position. The left control oil circuit is open, and the oil ports B1 and B2 are in operation. The oil in the first-stage cylinder a (8) overflows directly back to the cylinder (4) through the two-position three-way valve b (7), and the oil is returned to the oil ports A1 and A2. The oil port B1 on the left side of the three-position six-way valve (5) controls the two-position three-way valve a (6) to open and enters the left chamber of the first-stage oil cylinder b (9) and the second-stage oil cylinder b (11) connected to the first-stage oil cylinder b (9) through the two-position three-way valve a (6). Since the stiffness of the spring b (46) is much greater than the spring stiffness of the second-stage oil cylinder b (11), the oil first fills the second-stage oil cylinder b (11) and then fills the left chamber of the first-stage oil cylinder b (9). When the oil fills the left chamber of the first-stage oil cylinder b (9), the oil overcomes the limit spring b (46) and moves to the right, causing the valve core b (55) of the air valve b (13) to move to the right, so that the air source (14) is connected to the air chamber of the right suspension cylinder (20), thereby achieving inflation; The oil port B2 on the left side of the three-position six-way valve (5) controls the hydraulic control check valve a (15) to open, and the air chamber of the right suspension cylinder (20) is connected to the air control port of the air control check valve a (17). When the gas pressure in the right air chamber of the right suspension cylinder (20) reaches the set maximum pressure value, the air control check valve a (17) is reversed and leads to the atmosphere, thereby achieving the degassing of the left air chamber of the left suspension cylinder (19).

Images