Locking device for closed position of airplane nose cabin door
By designing a locking device containing hydraulic system and spring on a large transport machine, the problem that traditional locks cannot position the closed position of the cargo door on the machine head is solved, and the reliable locking and long life of the hatch door is achieved, reducing the Production cost.
Patent Information
- Application Number
- CN202411372029.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-29
- Publication Date
- 2024-12-20
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
The prior art cannot realize the positioning and fixing of the closed position of the cargo door on the head of a large transport machine, and traditional hook and loop locks or linkage mechanical pin locks cannot meet the needs of this special arrangement.
A locking device including an outer cylinder, a bracket, an end cover, a locking ring, a pin, a floating piston, a sliding piston, a central oil pipe, a spring and a ball were designed. The locking and locking of the hatch door through the cooperation of the hydraulic system and the spring are realized. Open to ensure that the closed position and fix of the lower cabin door in the form of the cargo warehouse door opened on the machine head.
It realizes reliable closing and fixing of large-scale transport cabin doors, avoids unlocking problems caused by hydraulic oil leakage, extends the service life of parts, and reduces production costs.
Smart Images
Figure CN119163311A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of manufacturing locking devices for aircraft, and relates to a locking device for closing a nose cabin door of an aircraft. Background Art
[0002] The existing cargo doors of large transport aircraft in China are all arranged at the rear or side of the fuselage, and the door structure mostly uses traditional hook and ring locks or linked mechanical latch locks to achieve the fixing and positioning of the door in the closed and open positions. In order to improve the ability of aircraft to transport large-sized cargo, it is necessary to develop a heavy-duty transport aircraft with a cargo door that can be flipped up and opened on the nose. Since traditional hook and ring locks or linked mechanical latch locks cannot be used on such large transport aircraft, it is urgent to develop a locking device for the closed position of the aircraft nose door that can be arranged on the cargo door connection frame and the fuselage bulkhead of such large transport aircraft to achieve the positioning and fixing of the closed position of the door. Summary of the invention
[0003] The purpose of the present invention is to solve the above-mentioned problems existing in the prior art and to provide a locking device for the closed position of the aircraft nose cabin door, so as to achieve the needs of positioning and fixing the closed position of the cabin door of a large transport aircraft in the form of a cargo door that flips up on the nose.
[0004] To achieve the above-mentioned purpose, the technical solution of the present invention is: a locking device for the closed position of the nose door of an aircraft, comprising an outer tube, a bracket, an end cover, a locking ring, a latch, a floating piston, a sliding piston, a central oil pipe, a spring and a plurality of ball bearings; the bracket is fixed to the aircraft frame, the locking ring is fixed to the door frame, the lower end of the outer tube is fixed to the upper end of the bracket, and the end cover is sealingly fixed to the upper end surface of the outer tube; the bracket, the outer tube, the latch, the floating piston, the sliding piston, the central oil pipe and the spring all have a central hole whose central axis coincides with the central axis, and the end cover has a central blind hole whose central axis coincides with the central axis of the latch; the lower end of the central oil pipe is provided with a shift plate, the shift plate can be slidably and sealingly connected in the central hole of the latch, and the upper end thereof is plugged and fixed on the central boss of the end cover; the central boss of the end cover is provided with an oil hole Ⅰ which is connected with the inner hole of the central oil pipe, and the end cover is provided with a pipe joint Ⅰ which is connected with the oil hole Ⅰ; the floating piston can slide The sealing sleeve is connected between the central oil pipe and the latch; the sliding piston is slidably and sealingly connected between the central oil pipe and the outer tube; a lower oil chamber is provided between the floating piston and the shift plate of the central oil pipe, and an upper oil chamber is provided between the sliding piston and the end cover; a spring is installed between the floating piston and the sliding piston; a driving step is provided on the outer circle of the floating piston, and a conical surface is provided on the outer circle of the bottom surface of the driving step; a plurality of ball accommodating holes are evenly opened on the peripheral wall of the upper end of the latch, and a circle of self-locking grooves is opened at the lower end of the central hole wall of the outer tube; when the latch is in the locked state, the spring is in a free extension state, and each ball is pressed in the self-locking groove of the outer tube by the outer conical surface of the bottom surface of the driving step of the floating piston; an oil hole connecting the lower oil chamber is opened at the lower end of the central oil pipe; an oil hole II is provided on the upper end wall of the outer tube, and a pipe joint II is sealed and installed on the oil hole II; an insertion hole facing the locking ring is opened on the lower end wall of the bracket, and a latch hole for the latch is opened on the locking ring.
[0005] Further preferably, the locking device further comprises a guide cover, the upper end of which is plugged and fixed to the lower end of the latch, and a chamfer is formed on the outer circle of the closed end of the guide cover.
[0006] Further preferably, the locking device also includes a buffer damping device, which is composed of a retaining ring, a filter and a throttle plate group; a mounting hole is opened on the upper end wall of the sliding piston, the throttle plate group is placed in the mounting hole, the filter cover is on the throttle plate group, and the retaining ring is clamped on the mounting hole to fix the throttle plate group; the lower end of the mounting hole is connected to the L-shaped oil hole; the L-shaped oil hole can be connected to the pipe joint II on the outer cylinder.
[0007] Further preferably, the bracket, the latch and the floating piston are respectively provided with transverse air holes, inclined air holes and vertical air holes, and the transverse air holes are connected with the inclined air holes and the vertical air holes through the gap between the bracket and the latch.
[0008] Further preferably, the spring is a wave spring, a rectangular spring, a butterfly spring, or a common coil spring.
[0009] The beneficial effect of the present invention is that the locking device of the present invention realizes the requirements of closing position positioning and fixing of the cabin door of a large transport aircraft in the form of a cargo door that flips up and opens on the nose. And after locking, after the hydraulic oil in the upper oil chamber and the lower oil chamber is returned, under the action of the spring and the ball, the locking device is still in a locked state, and there is no need to worry about the occurrence of the unlocking state of the locking device due to the leakage of the hydraulic oil, and the locking reliability is high. After the unlocking is completed, after the hydraulic oil in the upper oil chamber and the lower oil chamber is returned, the latch gradually moves to a fully extended state until it is locked under the combined action of the pressure difference caused by its own weight and the cross-sectional difference of the floating piston and the elastic force of the spring. At this time, the spring is in a naturally relaxed state, and the various components are no longer under pressure, which extends the service life of each component. And the present invention has a simple structure, is easy to manufacture, and has a low manufacturing cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention; Figure 2 for Figure 1 AA section view. DETAILED DESCRIPTION
[0011] The present invention is further described below in conjunction with the accompanying drawings and specific implementations.
[0012] like Figure 1 and Figure 2 As shown, the drawing adopts a horizontal placement. In actual use, the end cover 4 is placed on top and the bracket 2 is placed vertically below. The following embodiments are described in detail according to the actual use direction. The up and down in the text below refer to the right and left directions in the figure.
[0013] This embodiment includes an outer tube 3, a bracket 2, an end cover 4, a locking ring 1, a latch 6, a floating piston 8, a sliding piston 10, a central oil pipe 7, a spring 9 and 9 (3, 5, 6, 7, 8, 10, 11, etc.) balls 17. The more balls 17 there are, the greater the self-locking force is, and the more difficult it is to unlock. Therefore, a suitable number of balls 17 is set according to actual needs. Preferably, the spring 9 is a wave spring, a rectangular spring, a butterfly spring or an ordinary coil spring. The bracket 2 is fixed on the aircraft frame, the locking ring 1 is fixed on the cabin door frame, the lower end of the outer tube 3 is fixed on the upper end of the bracket 2, and the end cover 4 is sealed and fixed on the upper end surface of the outer tube 3. The bracket 2, the outer tube 3, the latch 6, the floating piston 8, the sliding piston 10, the central oil pipe 7 and the spring 9 all have a central hole whose central axis coincides, and the end cover 4 has a central blind hole whose central axis coincides with the central axis of the latch 6. Preferably, the locking device further comprises a guide cover 5, the upper end of which is plugged and fixed to the lower end of the latch 6, and the outer circle of the closed end of the lower end thereof is chamfered. The lower end of the central oil pipe 7 is provided with a shift plate, which is slidably and sealedly connected to the central hole of the latch 6, and the upper end of which is plugged and fixed to the central boss 21 of the end cover 4. The central boss 21 of the end cover 4 is provided with an oil hole I which is connected to the inner hole of the central oil pipe 7, and the end cover 4 is provided with a pipe joint I 22 which is connected to the oil hole I. The floating piston 8 is slidably and sealedly sleeved between the central oil pipe 7 and the latch 6. The sliding piston 10 is slidably and sealedly sleeved between the central oil pipe 7 and the outer cylinder 3. A lower oil chamber 27 is provided between the floating piston 8 and the shift plate of the central oil pipe 7, and an upper oil chamber 28 is provided between the sliding piston 10 and the end cover 4. A spring 9 is installed between the floating piston 8 and the sliding piston 10. A driving step is provided on the outer circle of the floating piston 8, and a conical surface 29 is provided on the outer circle of the bottom surface of the driving step. A plurality of ball receiving holes are evenly provided on the peripheral wall of the upper end of the latch 6, and an annular self-locking groove 16 is provided on the lower end of the central hole wall of the outer cylinder 3. When the latch 6 is in the locked state, the spring 9 is in a free extension state, and each ball 17 is pressed tightly in the self-locking groove 16 of the outer cylinder 3 by the outer conical surface 29 of the bottom surface of the driving step of the floating piston 8. An oil hole 30 connected to the lower oil chamber 27 is provided at the lower end of the central oil pipe 7. An oil hole II is provided on the upper end wall of the outer cylinder 3, and a pipe joint II 33 is sealed and installed on the oil hole II. An insertion hole facing the lock ring 1 is provided on the lower end wall of the bracket 2, and a latch hole for the latch 6 is provided on the lock ring 1. 14, 15, 17, 19 and 20 are all movable sealing rings, and 24 and 23 are all fixed sealing rings.
[0014] Preferably, the locking device further comprises a buffer damping device, which is composed of a retaining ring, a filter screen and a throttle plate group. A mounting hole is opened on the upper end wall of the sliding piston 10, the throttle plate group is placed in the mounting hole, the filter screen is covered on the throttle plate group, and the retaining ring is clamped on the mounting hole to fix the throttle plate group. The lower end of the mounting hole is connected to the L-shaped oil hole 25. The L-shaped oil hole 25 can be connected to the pipe joint II on the outer cylinder 3.
[0015] Preferably, the bracket 2 , the latch pin 6 and the floating piston 8 are respectively provided with a transverse air hole 26 , an inclined air hole 31 and a vertical air hole 32 , and the transverse air hole 26 is connected with the inclined air hole 31 and the vertical air hole 32 through the gap between the bracket 2 and the latch pin 6 .
[0016] Working principle: When the latch 6 is in the fully extended state (locked state), the ball 17 is pressed tightly into the self-locking groove 16 of the outer cylinder 3 by the outer conical surface 29 of the bottom surface of the driving step of the floating piston 8, thereby limiting the axial movement of the latch 6 and locking the latch 6 in the fully extended state. When the pipe joint Ⅰ22 is connected to the hydraulic oil, the hydraulic oil flows into the lower oil chamber 27 through the pipe joint Ⅰ22, the end cover 4, and the center hole of the center oil pipe 7. At this time, since the ball 17 fixes the relative position of the latch 6 and the outer tube 3 and cannot move, the hydraulic oil first pushes the floating piston 8 to overcome the spring force of the spring 9 and move upward. When the moving distance reaches the unlocking stroke, the floating piston 8 no longer provides radial support for the ball 17. The ball 17 is squeezed into the inside of the latch 6 under the combined action of the lateral thrust of the latch 6 and the radial extrusion of the self-locking groove 16 of the outer tube 3 to achieve unlocking. The hydraulic oil continues to push the latch 6 to move upward until it is completely unlocked. At this time, the cabin door is flipped up and opened under the push of the opening actuator, and the locking ring 1 is then released from the bracket 2. As there is no self-locking mechanism in the fully compressed state of the latch 6, the pipe joint Ⅰ22 should be kept continuously connected to the hydraulic oil during the hatch opening process to keep the latch 6 in the fully compressed state. When the locking ring 1 is completely removed from the bracket 2, the hydraulic oil is disconnected, and the pipe joints Ⅰ22 and Ⅱ are connected to the oil at the same time. At this time, the latch 6 gradually moves to the fully extended state under the combined action of its own weight, the pressure difference caused by the cross-sectional difference of the floating piston 8, and the elastic force of the spring 9 until it is locked.
[0017] When the hatch needs to be closed and locked, the working steps first follow the unlocking steps to move the latch 6 and keep it in a fully compressed state. At this time, after the hatch drives the lock ring 1 to move into the lock ring insertion hole of the bracket 2, the pipe joint Ⅰ22 is connected to the return oil, and the pipe joint Ⅱ33 is connected to the hydraulic oil. The hydraulic oil pushes the sliding piston 10 downward and pushes the latch 6 to move in the locking direction. When the hatch is deformed and the lock ring latch hole is not coaxial with the central axis of the latch 6, the guide angle of the guide cover 5 first contacts with the lock ring latch hole. Under the action of the hydraulic thrust, the lock ring 1 is corrected to the correct position. After the latch 6 continues to move until it is fully extended, the spring 9 overcomes the return oil pressure to push the floating piston 8 to move in the extension direction of the latch 6, and squeezes the ball 17 into the annular self-locking groove 16 of the outer tube 3, fixing the latch 6 in the fully extended position; disconnect the hydraulic oil, and connect the return oil to the pipe joint Ⅰ22 and the pipe joint Ⅱ33 at the same time. With the arrangement of the transverse air holes 26, the inclined air holes 31 and the vertical air holes 32, the air is directly connected to the cavity where the spring 9 is located. The change in the volume of the cavity caused by the compression and extension of the spring 9 will not cause a change in the air resistance, but is only affected by the elastic force of the spring 9. That is, the change in the distance between the floating piston 8 and the sliding piston 10 is only affected by the elastic force of the spring 9, without the influence of air resistance, and the accuracy is easier to control. When the hydraulic oil of the system accidentally leaks into the cavity where the spring 9 is located, it can be removed in time, thereby avoiding abnormal movement of the floating piston 8 and the sliding piston 10 caused by accidental leakage into the cavity where the spring 9 is located.
[0018] The buffer damping device is designed. At the end of the unlocking stroke, the latch 6 comes out of the latch hole 6 of the locking ring 1, and the friction force disappears suddenly. The rapid movement of the latch 6 may cause an impact on the end cover 4. The buffer damping device uses its own elasticity to play a buffering role, protects various components, and prolongs the service life.
[0019] Of course, the present invention has many other embodiments. Without violating the spirit and essence of the present invention, technicians familiar with the field can make corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should be regarded as improvements of equivalent technologies and belong to the protection scope of the claims of the present invention.
Claims
1. A locking device for closing the nose door of an aircraft, characterized in that: It includes an outer tube, a bracket, an end cover, a locking ring, a latch, a floating piston, a sliding piston, a central oil pipe, a spring and a plurality of ball bearings; the bracket is fixed on the aircraft frame, the locking ring is fixed on the cabin door frame, the lower end of the outer tube is fixed on the upper end of the bracket, and the end cover is sealed and fixed on the upper end face of the outer tube; the bracket, the outer tube, the latch, the floating piston, the sliding piston, the central oil pipe and the spring all have a central hole whose central axis coincides with the central axis, and the end cover has a central blind hole whose central axis coincides with the central axis of the latch; the lower end of the central oil pipe is provided with a shift plate, which is slidably and sealingly connected in the central hole of the latch, and the upper end of the shift plate is plugged and fixed on the central boss of the end cover; the central boss of the end cover is provided with an oil hole Ⅰ which is connected with the inner hole of the central oil pipe, and the end cover is provided with a pipe joint Ⅰ which is connected with the oil hole Ⅰ; the floating piston is slidably and sealingly sleeved between the central oil pipe and the latch; the sliding piston A slidable sealing sleeve is connected between the central oil pipe and the outer cylinder; a lower oil chamber is provided between the floating piston and the shift plate of the central oil pipe, and an upper oil chamber is provided between the sliding piston and the end cover; a spring is installed between the floating piston and the sliding piston; a driving step is provided on the outer circle of the floating piston, and a conical surface is provided on the outer circle of the bottom surface of the driving step; a plurality of ball accommodating holes are evenly opened on the peripheral wall of the upper end of the latch, and a circle of self-locking grooves is opened at the lower end of the central hole wall of the outer cylinder; when the latch is in the locked state, the spring is in a free extension state, and each ball is pressed in the self-locking groove of the outer cylinder by the outer conical surface of the bottom surface of the driving step of the floating piston; an oil through hole connected to the lower oil chamber is opened at the lower end of the central oil pipe; an oil hole II is provided on the upper end wall of the outer cylinder, and a pipe joint II is sealed and installed on the oil hole II; an insertion hole facing the locking ring is opened on the lower end wall of the bracket, and a latch hole for the latch is opened on the locking ring.
2. The locking device for closing the aircraft nose door according to claim 1, characterized in that: The locking device also includes a buffer damping device, which is composed of a retaining ring, a filter and a throttle plate group; a mounting hole is opened on the upper end wall of the sliding piston, the throttle plate group is placed in the mounting hole, the filter cover is on the throttle plate group, and the retaining ring is clamped on the mounting hole to fix the throttle plate group; the lower end of the mounting hole is connected to the L-shaped oil hole; the L-shaped oil hole can be connected to the pipe joint II on the outer cylinder.
3. The locking device for closing the aircraft nose door according to claim 1 or 2, characterized in that: The locking device also includes a guide cover, the upper end of which is plugged and fixed to the lower end of the latch, and a chamfer is formed on the outer circle of the closed end of the guide cover.
4. The locking device for closing the aircraft nose door according to claim 3, characterized in that: The bracket, the latch and the floating piston are respectively provided with transverse air holes, inclined air holes and vertical air holes. The transverse air holes are connected with the inclined air holes and the vertical air holes through the gap between the bracket and the latch.
5. The locking device for closing the aircraft nose door according to claim 4, characterized in that: The spring is a wave spring, a rectangular spring, a butterfly spring or a common helical spring.
6. The locking device for closing the aircraft nose door according to claim 1 or 2, characterized in that: The bracket, the latch and the floating piston are respectively provided with transverse air holes, inclined air holes and vertical air holes. The transverse air holes are connected with the inclined air holes and the vertical air holes through the gap between the bracket and the latch.
7. The locking device for closing the aircraft nose door according to claim 6, characterized in that: The spring is a wave spring, a rectangular spring, a butterfly spring or a common helical spring.
8. The locking device for closing the aircraft nose door according to claim 1 or 2, characterized in that: The spring is a wave spring, a rectangular spring, a butterfly spring or a common helical spring.
9. The locking device for closing the aircraft nose door according to claim 3, characterized in that: The spring is a wave spring, a rectangular spring, a butterfly spring or a common helical spring.