Hydraulic differential valve for controlling aircraft yaw and turn

Abstract

A kind of hydraulic differential valve for controlling aircraft deviation and turning, comprising a housing, the housing has two identical hydraulic cavities left and right, two hydraulic cavities share a pressure input port and a return port, the pressure input port is provided with an oil inlet nozzle, the return port is provided with a return oil nozzle, the return oil nozzle is connected to the hydraulic oil tank, left and right pressure output ports are respectively provided with left and right output nozzles, the two hydraulic cavities on the housing are provided with identical sleeves, the sleeve is provided with a piston, the piston can slide in the sleeve, the piston bottom is provided with a return spring, the sleeve is installed in the housing using a nipple, the nipple is provided with a top rod, the top rod can slide in the nipple, the lower end of the top rod abuts against the piston, and the upper end extends out of the nipple, a rocker arm and a control force arm are hinged to the housing through a rotating shaft, the control force arm is located above the rocker arm, the rocker arm two ends are provided with protrusions corresponding to the position of the top rod, a control lever is hinged to the control force arm through a hinge shaft, and the control force arm is provided with adjusting screws corresponding to the two ends of the rocker arm.

Description

Technical Field

[0001] This invention relates to the field of hydraulic differential valve technology, and in particular to a hydraulic differential valve for controlling aircraft steering and turning. Background Technology

[0002] During takeoff and landing, aircraft may deviate from their course due to wind direction and runway conditions. If not corrected in time, the aircraft may run off the runway, causing damage to the aircraft and injuries to personnel. Furthermore, to achieve a turn during taxiing, the left and right wheels need to taxi at different speeds. To achieve correction and turning, different pressures need to be applied between the brake discs of the left and right wheels, i.e., differential braking. Aircraft brakes come in various forms, including pneumatic brakes, hydraulic brakes, and fly-by-wire brakes. Many aircraft models use hydraulic brakes. However, existing hydraulic differential valves for aircraft brakes are relatively complex in structure, difficult to operate, and have low efficiency. Summary of the Invention

[0003] To address the problems mentioned in the background section, the present invention provides a hydraulic differential valve for controlling aircraft steering and turning.

[0004] This invention discloses the following technical solution: a hydraulic differential valve for controlling aircraft steering and turning, comprising a housing, the housing having two identical hydraulic chambers, the two hydraulic chambers sharing a pressure input port and a return port, an inlet nozzle at the pressure input port, a return nozzle at the return port, the return nozzle being connected to a hydraulic oil tank, and left and right output nozzles respectively at the left and right pressure output ports, identical sleeves installed in the two hydraulic chambers of the housing, a piston installed in the sleeve, the piston being able to slide in the sleeve, a return spring installed at the bottom of the piston, the two ends of the return spring abutting against the piston and the lower end face of the hydraulic chamber of the housing, respectively, the sleeve being installed in the housing using a threaded sleeve, a push rod installed in the threaded sleeve, the push rod being able to slide in the threaded sleeve, the lower end of the push rod abutting against the piston, the upper end extending out of the threaded sleeve, a rocker arm and an operating lever hinged to the housing via a pivot, the operating lever being located above the rocker arm, the two ends of the rocker arm having protrusions corresponding to the positions of the push rod, the operating lever being hinged to the operating lever via a hinge shaft, the operating lever having adjusting screws corresponding to the two ends of the rocker arm.

[0005] Furthermore, the sleeve sidewall is provided with three annular grooves, and a radial oil passage hole is provided in the middle of the annular groove. The radial oil passage hole is arranged from bottom to top as a pressure input hole, a pressure output hole, and a return oil hole. The pressure input hole, pressure output hole, and return oil hole are respectively connected to the pressure input port, pressure output port, and return oil port of the hydraulic cavity of the housing. Three sealing rings are provided between the sleeve and the hydraulic cavity, and the sealing rings are spaced apart from the annular grooves.

[0006] Furthermore, the adjusting screw is mounted on the operating arm via a locking nut.

[0007] Furthermore, the threaded sleeve is threaded onto the housing, and a sealing ring is provided between the threaded sleeve and the push rod, and a sealing ring is provided between the threaded sleeve and the housing.

[0008] Furthermore, sealing rings are provided between the oil inlet nozzle, oil return nozzle, left output nozzle, and right output nozzle and the housing.

[0009] Beneficial effects: Compared with the prior art, the hydraulic differential valve for controlling aircraft deviation and turning of the present invention has two hydraulic chambers in the housing. The two hydraulic chambers share a pressure input port and an oil return port. The pressure of the two hydraulic chambers is output to the left and right wheel braking devices through the left and right pressure output ports respectively. The hydraulic chambers are equipped with two identical sleeves, pistons and push rods. A rocker arm and an operating arm are hinged to the housing. The two ends of the rocker arm correspond to the push rod. An operating lever is hinged on the operating arm. By pushing and pulling the operating lever, the operating arm is rotated. The adjusting screw on the operating arm presses against the middle end of the rocker arm. The rocker arm rotates and presses down the push rod. The push rod presses down the piston to control the hydraulic oil flow in the sleeve, realizing differential braking. It can be used to correct wheel deviation when the aircraft is braking. It has a simple structure, is easy to operate and has high braking efficiency. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of the present invention;

[0011] In the diagram: 1-Housing, 2-Inlet nozzle, 3-Return nozzle, 4-Left outlet nozzle, 5-Right outlet nozzle, 6-Sleeve, 7-Piston, 8-Reset spring, 9-Screw sleeve, 10-Push rod, 11-Rock arm, 12-Operating lever, 13-Shaft, 14-Operating lever, 15-Hinge shaft, 16-Adjusting screw, 17-Locking nut. Detailed Implementation

[0012] like Figure 1As shown, a hydraulic differential valve for controlling aircraft steering and turning includes a housing 1 with two identical hydraulic chambers (left and right). The two chambers share a pressure input port and a return port. An inlet nozzle 2 at the pressure input port supplies hydraulic oil to the differential valve, and a return nozzle 3 at the return port connects to a hydraulic oil tank. A left output nozzle 4 and a right output nozzle 5 are respectively located at the left and right pressure output ports, connecting to the left and right wheel brake devices to control braking. Identical sleeves 6 are installed in the two hydraulic chambers of the housing 1, and pistons 7 are installed inside the sleeves 6. Pistons 7 can slide within the sleeves 6 to adjust the flow rate of hydraulic oil. A return spring 8 is located at the bottom of the piston 7, with its two ends abutting against the piston 7 and the lower end face of the hydraulic chamber of the housing 1, respectively, to reset the piston 7. The sleeve 6 is installed inside the housing 1 using a threaded sleeve 9. A push rod 10 is provided inside the threaded sleeve 9. The push rod 10 can slide inside the threaded sleeve 9. The lower end of the push rod 10 abuts against the piston 7, and the upper end extends out of the threaded sleeve 9. The rocker arm 11 and the operating arm 12 are hinged to the housing 1 via a rotating shaft 13. The operating arm 12 is located above the rocker arm 11. Both ends of the rocker arm 11 have protrusions corresponding to the positions of the push rod 10. The operating lever 14 is hinged to the operating arm 12 via a hinge shaft 15. The operating arm 12 has adjusting screws 16 corresponding to the two ends of the rocker arm 11. Pushing and pulling the operating lever 14 causes the operating arm 12 to drive the adjusting screws 16 to rotate. The adjusting screws 16 press down on the rocker arm 11. The rocker arm 11 rotates and presses down on the push rod 10. The push rod 10 presses down on the piston 7, adjusting the position of the piston 7 inside the sleeve 6 to regulate the flow of hydraulic oil and control the braking force.

[0013] The sleeve 6 has three annular grooves on its side wall, and a radial oil passage hole is provided in the middle of the annular groove. The radial oil passage hole is arranged from bottom to top as a pressure input hole, a pressure output hole, and a return oil hole. The pressure input hole, pressure output hole, and return oil hole are respectively connected to the pressure input port, pressure output port, and return oil port of the hydraulic cavity of the housing 1. Three sealing rings are provided between the sleeve 6 and the hydraulic cavity. The sealing rings are spaced apart from the annular grooves. The sealing rings can isolate the pressure input port, pressure output port, and return oil port of the hydraulic cavity of the housing 1. The adjusting screw 16 is installed on the operating arm 12 by the locking nut 17. The distance between the adjusting screw 16 and the rocker arm 11 is adjusted. When the stroke of the control lever 14 is determined, the adjusting screw 16 is lowered, and the downward stroke of the push rod 10 and the piston 7 is increased, which increases the output pressure of the control lever 14 at the same stroke. The screw sleeve 9 is installed on the housing 1 by threads. A sealing ring is provided between the screw sleeve 9 and the push rod 10, and a sealing ring is provided between the screw sleeve 9 and the housing 1 to prevent the oil in the housing 1 from leaking from the screw sleeve 9. The oil inlet nozzle 2, oil return nozzle 3, left output nozzle 4 and right output nozzle 5 are all provided with sealing rings between them and the housing 1 to prevent the hydraulic oil in the housing 1 from leaking.

[0014] The specific implementation process is as follows:

[0015] During normal braking, the control lever 14 is in the neutral position. The system brake hydraulic pressure is input into the pressure input port of the housing 1 through the oil inlet nozzle 2, and then output to the wheel brake device through the pressure input hole of the sleeve 6 and the left and right pressure output holes of the housing 1 via the left output nozzle 4 and the right output nozzle 5. The left and right pistons 7 are in a balanced state under the action of the return spring 8. The oil passage area of ​​the pressure input holes of the left and right sleeves 6 is equal. The pressure output to the wheel brake device by the left output nozzle 4 and the right output nozzle 5 is the same as the system pressure.

[0016] During differential braking, after pushing the control lever 14 to swing a certain angle, the control arm 12 rotates to the right, and the right adjusting screw 16 presses the rocker arm 11 to rotate clockwise. The right piston 7 moves down, and the left piston 7 moves up. The oil passage area of ​​the pressure input hole of the right sleeve 6 increases, while the pressure output from the right output nozzle 5 to the wheel brake remains unchanged. The oil passage area of ​​the pressure input hole of the left sleeve 6 decreases, and the pressure output from the left output nozzle 4 to the wheel brake decreases, thus achieving differential braking. When pushing the control lever 14 to swing to the maximum angle, the left piston 7 moves up and blocks the pressure input hole of the left sleeve 6. The left output nozzle 4 connects with the oil return hole of the left sleeve 6. The internal pressure of the wheel brake flows back to the oil tank through the left output nozzle 4, the left pressure output port of the housing 1, the pressure output hole of the left sleeve 6, the oil return hole of the left sleeve 6, and the oil return port of the housing 1, and the braking pressure drops to zero. The pressure output from the right output nozzle 5 to the wheel brake remains unchanged, thus achieving maximum differential braking. The pressure difference between the right output nozzle 5 and the left output nozzle 4 increases with the increase of the operating force.

[0017] During reverse differential braking, pulling the control lever 14 to swing it at a certain angle increases the oil flow area of ​​the pressure input port of the left sleeve 6, while the pressure output from the left output nozzle 4 to the wheel brake remains unchanged; conversely, the oil flow area of ​​the pressure input port of the right sleeve 6 decreases, reducing the pressure output from the right output nozzle 5 to the wheel brake, thus achieving differential braking. After pulling the control lever 14 to its maximum swing angle, the right piston 7 moves upward to block the pressure input port of the right sleeve 6, connecting the right output nozzle 5 with the return oil port of the right sleeve 6. The internal pressure of the wheel brake flows back to the oil tank through the right output nozzle 5, the right pressure output port of the housing 1, the pressure output port of the right sleeve 6, the return oil port of the right sleeve 6, and the return oil port of the housing 1, causing the brake pressure to drop to zero; the pressure output from the left output nozzle 4 to the wheel brake remains unchanged, achieving maximum differential braking. The pressure difference between the left output nozzle 4 and the right output nozzle 5 increases with the increase of the operating force.

[0018] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A hydraulic differential valve for controlling aircraft steering and turning, comprising a housing (1), characterized in that: The housing (1) has two identical hydraulic chambers, one on the left and one on the right. The two hydraulic chambers share a pressure input port and a return port. The pressure input port is equipped with an inlet nozzle (2), and the return port is equipped with a return nozzle (3). The return nozzle (3) is connected to the hydraulic oil tank. The left and right pressure output ports are respectively equipped with a left output nozzle (4) and a right output nozzle (5). The two hydraulic chambers on the housing (1) are equipped with identical sleeves (6). The sleeves (6) are equipped with pistons (7). The pistons (7) can slide inside the sleeves (6). The bottom of the pistons (7) is equipped with return springs (8). The two ends of the return springs (8) abut against the pistons (7) and the lower end faces of the hydraulic chambers of the housing (1), respectively. The sleeve (9) is installed inside the housing (1) with the sleeve (6). The sleeve (9) has a push rod (10) inside it. The push rod (10) can slide inside the sleeve (9). The lower end of the push rod (10) abuts against the piston (7), and the upper end extends out of the sleeve (9). The rocker arm (11) and the operating arm (12) are hinged to the housing (1) through the pivot (13). The operating arm (12) is located above the rocker arm (11). The rocker arm (11) has protrusions at both ends corresponding to the position of the push rod (10). The operating lever (14) is hinged to the operating arm (12) through the hinge shaft (15). The operating arm (12) has adjusting screws (16) corresponding to the two ends of the rocker arm (11). The sleeve (6) has three annular grooves on its side wall. A radial oil passage hole is provided in the middle of the annular groove. The radial oil passage hole is arranged from bottom to top as a pressure input hole, a pressure output hole and a return oil hole. The pressure input hole, pressure output hole and return oil hole are respectively connected to the pressure input port, pressure output port and return oil port of the hydraulic cavity of the housing (1). Three sealing rings are provided between the sleeve (6) and the hydraulic cavity. The sealing rings are spaced apart from the annular grooves.

2. The hydraulic differential valve for controlling aircraft steering and turning according to claim 1, characterized in that: The adjusting screw (16) is mounted on the operating lever (12) by a locking nut (17).

3. The hydraulic differential valve for controlling aircraft steering and turning according to claim 1, characterized in that: The screw sleeve (9) is threaded onto the housing (1), and a sealing ring is provided between the screw sleeve (9) and the push rod (10). A sealing ring is also provided between the screw sleeve (9) and the housing (1).

4. The hydraulic differential valve for controlling aircraft steering and turning according to claim 1, characterized in that: The oil inlet nozzle (2), oil return nozzle (3), left output nozzle (4), and right output nozzle (5) are all provided with sealing rings between themselves and the housing (1).

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