A hydraulic jack for aircraft

Abstract

This utility model discloses a hydraulic jack for aircraft, comprising a hydraulic body including a piston rod, an actuating cylinder, an oil reservoir, and a base. A high-speed manual pump and a high-pressure manual pump are connected in parallel on the base. The oil outlets of both the high-speed and high-pressure manual pumps are connected to the actuating cylinder. A reversing valve and a return oil switch are provided on the base. The reversing valve controls the lifting and lowering of the piston rod, and the return oil switch controls the lowering of the piston rod. This utility model, by adding a high-speed manual pump, allows the device to operate at low loads to increase the lifting speed, while the high-pressure manual pump retains its heavy-load capacity. The two pumps work together to adapt to different operating conditions. Simultaneously, the addition of a reversing valve allows direct control of the oil return to the lowering cylinder when the load is limited by operating space and external force cannot be applied. Under heavy loads, the reversing valve and return oil switch provide functional redundancy, offering dual lowering operation paths and improving system reliability.

Description

Technical Field

[0001] This utility model relates to the field of aircraft maintenance technology, specifically to a hydraulic jack for aircraft. Background Technology

[0002] When assembling, inspecting, maintaining, and leveling aircraft on the ground, jacks are required to support the aircraft. Existing aircraft hydraulic jacks primarily consist of an oil reservoir, oil filter, check valve, hand pump, safety valve, selector switch, hydraulic cylinder, air filter, pipe fittings, and connecting pipes. These components are assembled using separate parts connected by pipes. The working principle is as follows: hydraulic oil from the reservoir is filtered, pressurized by the hand pump, and injected into the hydraulic cylinder through the check valve, causing the piston rod to rise and lift the aircraft. When the pressure exceeds the rated value, the oil returns to the oil tank through the safety valve. Opening the selector switch returns the oil from the hydraulic cylinder to the oil tank, causing the piston rod to descend and lower the aircraft.

[0003] To ensure sufficient pressure for lifting aircraft, hand-cranked pumps are typically designed with a small displacement (limited amount of oil delivered per cranking stroke) to achieve the required high pressure. However, a small displacement means that even with rapid cranking, the amount of oil injected into the hydraulic cylinder per unit time is limited, resulting in a slow piston rod rise, low pressurization efficiency, and extremely inconvenient operation. Utility Model Content

[0004] The purpose of this invention is to provide a hydraulic jack for aircraft to solve the problems mentioned in the background section.

[0005] To solve the above-mentioned technical problems, this utility model provides a hydraulic jack for aircraft, which includes a hydraulic body. The hydraulic body includes a piston rod, an actuating cylinder, an oil reservoir, and a base. A high-speed manual pump and a high-pressure manual pump are connected in parallel on the base. The oil outlets of the high-speed manual pump and the high-pressure manual pump are both connected to the actuating cylinder. A reversing valve and a return oil switch are provided on the base. The reversing valve is used to control the lifting and lowering of the piston rod, and the return oil switch is used to control the lowering of the piston rod.

[0006] Furthermore, a safety nut is threaded onto the top of the piston rod.

[0007] Furthermore, there are multiple safety nuts, which are respectively sleeved on the top of the piston rod along the longitudinal direction. The piston rod is a multi-stage piston rod, and each multi-stage piston rod corresponds to one of the multiple safety nuts.

[0008] Furthermore, a vent plug is provided at the top of the oil storage tank.

[0009] Furthermore, the hydraulic body is provided with multiple support components on its outer side. The support components include a tripod, casters, and an adjusting component. The tripod is used to support the hydraulic body, the casters are mounted on the tripod, and the adjusting component is used to adjust the height of the casters.

[0010] Furthermore, the tripod includes a support rod, a connecting rod, and a base. The first end of the support rod is hinged to the hydraulic body, the first end of the connecting rod is hinged to the hydraulic body, the second end of the connecting rod is hinged to the second end of the support rod, and the base is located outside the hydraulic body and is rotatably connected to the second end of the connecting rod and the second end of the support rod.

[0011] Furthermore, each of the support components is provided with a traction screw, which is hinged to the corresponding strut.

[0012] Furthermore, the adjusting component includes a lower sleeve, an upper sleeve, a threaded rod, and a connecting pipe. The lower sleeve is installed on the top of the caster. The upper sleeve is sleeved on the lower sleeve and rotatably connected to it. The threaded end of the threaded rod passes through the upper sleeve and the lower sleeve in sequence. The threaded rod is threadedly connected to the upper sleeve and detachably connected to the caster. The two ends of the connecting pipe are respectively connected to the tripod and the upper sleeve.

[0013] The beneficial effects of this invention are as follows: By adding a high-speed manual pump, the device can increase the lifting speed under low load conditions, while the high-pressure manual pump retains its heavy-load capacity. The two pumps work together to adapt to different working conditions. Simultaneously, the addition of a reversing valve allows for direct control of the oil circuit to return to the lowering cylinder when the load is limited by operating space and external force cannot be applied. Under heavy load conditions, the reversing valve and return oil switch provide redundancy, offering dual lowering operation methods and improving system reliability. Attached Figure Description

[0014] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present utility model.

[0015] Figure 2 This is a cross-sectional structural diagram of an embodiment of the present utility model.

[0016] The components include: 1. Hydraulic main body; 2. High-speed manual pump; 3. High-pressure manual pump; 4. Reversing valve; 5. Oil return switch; 6. Safety nut; 7. Breather plug; 8. Support assembly; 9. Traction screw.

[0017] 11. Piston rod; 12. Actuating cylinder; 13. Oil reservoir; 14. Base; 15. Top head; 81. Tripod; 82. Casters; 83. Adjusting components;

[0018] 811. Support rod; 812. Connecting rod; 813. Base; 831. Lower sleeve; 832. Upper sleeve; 833. Threaded rod; 834. Connecting pipe. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only one embodiment of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] To make the objectives, technical solutions and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0021] In the following description, references to "an embodiment," "an embodiment," "an example," "example," etc., indicate that the described embodiment or example may include a particular feature, structure, characteristic, property, element, or limitation, but not every embodiment or example necessarily includes that particular feature, structure, characteristic, property, element, or limitation. Furthermore, the repeated use of the phrase "an embodiment according to this application," while possibly referring to the same embodiment, does not necessarily refer to the same embodiment.

[0022] like Figure 1-2 As shown, this utility model discloses a hydraulic jack for aircraft, comprising a hydraulic body 1, which includes a piston rod 11, an actuating cylinder 12, an oil reservoir 13, and a base 14. A high-speed manual pump 2 and a high-pressure manual pump 3 are connected in parallel on the base 14. The oil outlets of both the high-speed manual pump 2 and the high-pressure manual pump 3 are connected to the actuating cylinder 12. A reversing valve 4 and a return oil switch 5 are provided on the base 14. The reversing valve 4 controls the lifting and lowering of the piston rod 11, and the return oil switch 5 controls the lowering of the piston rod 11. In this embodiment, the base 14 has a high-pressure oil circuit and a low-pressure oil circuit. Oil filters are installed under both the high-speed manual pump 2 and the high-pressure manual pump 3 to prevent impurities from being sucked into the pumps and cylinders. A safety valve is installed on the high-pressure oil circuit. When the load exceeds 6000 kg, the pressurized oil leaks through the safety valve into the oil reservoir 13 to prevent the jack from overloading and causing an accident. The piston rod 11 has a top head 15 adapted to the aircraft's top socket.

[0023] When the aircraft needs to be lifted, the return oil switch 5 should be tightened and the handle of the reversing valve 4 should be rotated to the rising position, that is, the reversing valve 4 is in the oil supply position. When the device is unloaded, the high-speed manual pump 2 should be cranked to make the piston rod 11 rise quickly to the top of the aircraft, and then the high-pressure manual pump 3 should be cranked to make the piston rod 11 rise slowly to lift the aircraft.

[0024] When lowering the aircraft, slowly rotate the directional valve 4 handle to the descent position, i.e., the directional valve 4 is in the return oil position. Controlling the rotation angle of the directional valve 4 handle can adjust the descent speed under heavy load, ensuring a smooth descent of the aircraft. Furthermore, when the device is unloaded, the manual pump can be cranked to lower the jack; simultaneously, loosen the return oil switch 5. Loosening the return oil switch 5 by no more than 2-3 turns will quickly lower the aircraft to the lowest position.

[0025] When the jack is under low load and the operating space is limited, external force cannot be applied. The reversing valve 4 can be used to operate the manual pump to lower the oil cylinder. Under heavy load, the reversing valve 4 and the return oil switch 5 are equivalent, and operating either one can lower the oil cylinder.

[0026] This invention adds a high-speed manual pump 2, allowing the device to operate at low loads to increase the lifting speed, while the high-pressure manual pump 3 retains its heavy-load capacity. The two pumps work together to adapt to different working conditions. Simultaneously, a reversing valve 4 is added. When the load is limited by operating space and external force cannot be applied, the reversing valve 4 directly controls the oil circuit to return to the lowering cylinder. Under heavy loads, the reversing valve 4 and the return oil switch 5 provide functional redundancy, offering dual lowering operation methods and improving system reliability.

[0027] In one embodiment, a safety nut 6 is threaded onto the top of the piston rod 11. After the piston rod 11 rises to lift the aircraft, the safety nut 6 is manually tightened to ensure it is in contact with the load support surface, preventing the piston rod 11 from falling due to hydraulic failure.

[0028] In one embodiment, there are multiple safety nuts 6, which are respectively sleeved on the top of the piston rod 11 along the longitudinal direction. The piston rod 11 is a multi-stage piston rod 11, and the multi-stage piston rod 11 corresponds one-to-one with the multiple safety nuts 6 to form a stepped locking structure. That is, the multiple safety nuts 6 can correspond to the multi-stage piston rod 11. When the piston rod 11 extends step by step, the safety nuts 6 are locked in sequence to form a segmented support.

[0029] In one embodiment, a vent plug 7 is provided at the top of the oil reservoir 13. When the vent plug 7 is opened, hydraulic oil can be injected; when it is loosened, air in the oil reservoir 13 can be released. When using this device, loosening the vent plug 7 allows the oil reservoir 13 to communicate with the atmosphere, eliminating negative pressure during hydraulic system operation and ensuring smooth flow of hydraulic oil into the pump body. After use, the vent plug 7 is closed to prevent rainwater and debris from entering the oil reservoir 13.

[0030] In one embodiment, a plurality of support components 8 are provided on the outer side of the hydraulic body 1. Each support component 8 includes a tripod 81, casters 82, and an adjusting member 83. The tripod 81 supports the hydraulic body 1, the casters 82 are mounted on the tripod 81, and the adjusting member 83 adjusts the height of the casters 82. In this embodiment, three support components 8 are arranged in a ring at equal intervals on the outer side of the hydraulic body 1. In the supported state, the adjusting member 83 retracts the casters 82, and the tripod 81 contacts the ground. In the moving state, the adjusting member 83 lowers the casters 82, the tripod 81 disengages from the ground, and the casters 82 contact the ground to bear the full weight.

[0031] In one embodiment, the tripod 81 includes a support rod 811, a connecting rod 812, and a base 813. The first end of the support rod 811 is hinged to the hydraulic body 1, the first end of the connecting rod 812 is hinged to the hydraulic body 1, the second end of the connecting rod 812 is hinged to the second end of the support rod 811, the base 813 is located outside the hydraulic body 1 and is rotatably connected to the second end of the connecting rod 812 and the second end of the support rod 811, and the base 813 is in contact with the ground.

[0032] In one embodiment, any support component 8 is provided with a traction screw 9, which is hinged to a corresponding support rod 811. A handle can be installed on the traction screw 9, and the handle has an internal thread adapted to the traction screw 9, allowing the device to be dragged in a low position.

[0033] In one embodiment, the adjusting member 83 includes a lower sleeve 831, an upper sleeve 832, a threaded rod 833, and a connecting pipe 834. The lower sleeve 831 is mounted on top of the caster 82, and the upper sleeve 832 is sleeved on the lower sleeve 831 and rotatably connected to it. The threaded end of the threaded rod 833 passes through the upper sleeve 832 and the lower sleeve 831 in sequence. The threaded rod 833 is threadedly connected to the upper sleeve 832 and detachably connected to the caster 82. The two ends of the connecting pipe 834 are respectively connected to the tripod 81 and the upper sleeve 832, that is, rotating the threaded rod 833 can drive the threaded rod 833 to move upward or downward.

[0034] The workflow of this utility model is as follows:

[0035] Preparations before use:

[0036] 1) Check if the hydraulic oil in the oil reservoir 13 is sufficient;

[0037] 2) Loosen the vent plug 7 to allow the oil reservoir 13 to communicate with the atmosphere;

[0038] 3) Align the jack head 15 with the support point on the aircraft, and make sure the jack is placed vertically and the three points are firmly on the ground.

[0039] When lifting the plane:

[0040] 1) Tighten the oil return switch 5, being careful not to apply excessive force;

[0041] 2) Rotate the handle of directional valve 4 to the up position, that is, directional valve 4 is in the oil supply position;

[0042] 3) When the device is unloaded, crank the high-speed manual pump 2 to quickly raise the piston rod 11 to the top of the aircraft, and crank the high-pressure manual pump 3 to slowly raise the piston rod 11. Note that the raising speed of the three jacks should be coordinated to prevent tilting and accidents.

[0043] 4) After lifting the aircraft, tighten the safety nut 6 until it is flush with the support surface.

[0044] When putting down the plane:

[0045] 1) Operate this device to lift the aircraft upwards by 2-3mm;

[0046] 2) Rotate the safety nut 6 to raise it to a certain height;

[0047] 3) Slowly rotate the handle of the reversing valve 4 to the descent position, that is, the reversing valve 4 is in the return oil position. The rotation angle of the reversing valve 4 handle can be controlled to adjust the descent speed of the piston rod 11 under heavy load; note that the three jacks should be synchronized to ensure the aircraft descends smoothly.

[0048] 4) When the device is unloaded, the manual pump can be cranked to lower the jack;

[0049] 5) Loosen the return oil switch 5. Loosening the return oil switch 5 by no more than 2 to 3 turns will quickly lower it to the lowest position.

[0050] 6) Tighten the vent plug 7 after use;

[0051] 7) Connect the internal thread of the handle to the traction screw 9. The jack can be dragged when it is low. Rotate the threaded rod 833 of the adjusting part 83 to adjust the height of the caster 82. The jack can also be pulled by the handle after the three outriggers are off the ground.

[0052] This invention adds a high-speed manual pump 2, allowing the device to operate at low loads to increase the lifting speed, while the high-pressure manual pump 3 retains its heavy-load capacity. The two pumps work together to adapt to different working conditions. Simultaneously, a reversing valve 4 is added. When the load is limited by operating space and external force cannot be applied, the reversing valve 4 directly controls the oil circuit to return to the lowering cylinder. Under heavy loads, the reversing valve 4 and the return oil switch 5 provide functional redundancy, offering dual lowering operation methods and improving system reliability.

[0053] The above description of the disclosed embodiments enables those skilled in the art to implement or use this invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, this invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A hydraulic jack for aircraft, comprising a hydraulic body, said hydraulic body including a piston rod, an actuating cylinder, an oil reservoir, and a base, characterized in that: A high-speed manual pump and a high-pressure manual pump are connected in parallel on the base. The oil outlets of the high-speed manual pump and the high-pressure manual pump are both connected to the actuating cylinder. A reversing valve and a return oil switch are provided on the base. The reversing valve is used to control the piston rod to rise and fall, and the return oil switch is used to control the piston rod to fall.

2. The hydraulic aircraft jack of claim 1, wherein: A safety nut is threaded onto the top of the piston rod.

3. Hydraulic jack for aircraft according to claim 2, characterized in that: There are multiple safety nuts, which are respectively sleeved on the top of the piston rod along the longitudinal direction. The piston rod is a multi-stage piston rod, and each multi-stage piston rod corresponds to one of the multiple safety nuts.

4. The hydraulic aircraft jack of claim 1, wherein: A vent plug is installed at the top of the oil storage tank.

5. The hydraulic aircraft jack of claim 1, wherein: The hydraulic body is provided with multiple support components on its outer side. The support components include a tripod, casters, and an adjusting component. The tripod is used to support the hydraulic body, the casters are mounted on the tripod, and the adjusting component is used to adjust the height of the casters.

6. A hydraulic aircraft jack as claimed in claim 5 wherein: The tripod includes a support rod, a connecting rod, and a base. The first end of the support rod is hinged to the hydraulic body, the first end of the connecting rod is hinged to the hydraulic body, the second end of the connecting rod is hinged to the second end of the support rod, and the base is located outside the hydraulic body and is rotatably connected to the second end of the connecting rod and the second end of the support rod.

7. A hydraulic aircraft jack as claimed in claim 6 wherein: Each of the support components is provided with a traction screw, which is hinged to the corresponding strut.

8. The hydraulic aircraft jack of claim 5, wherein: The adjusting component includes a lower sleeve, an upper sleeve, a threaded rod, and a connecting pipe. The lower sleeve is installed on the top of the caster. The upper sleeve is sleeved on the lower sleeve and rotatably connected to it. The threaded end of the threaded rod passes through the upper sleeve and the lower sleeve in sequence. The threaded rod is threadedly connected to the upper sleeve and detachably connected to the caster. The two ends of the connecting pipe are respectively connected to the tripod and the upper sleeve.

Images