CN210416963U - Telex antiskid braking system with variable gain - Google Patents
Telex antiskid braking system with variable gain Download PDFInfo
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- CN210416963U CN210416963U CN201921055891.5U CN201921055891U CN210416963U CN 210416963 U CN210416963 U CN 210416963U CN 201921055891 U CN201921055891 U CN 201921055891U CN 210416963 U CN210416963 U CN 210416963U
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Abstract
An oil inlet of an electromagnetic hydraulic lock is communicated with a hydraulic source, and an oil return port of the electromagnetic hydraulic lock is communicated with an oil tank; an oil outlet of the electromagnetic hydraulic lock is communicated with an oil inlet of the electro-hydraulic pressure servo valve. An oil outlet of the electro-hydraulic pressure servo valve is communicated with an oil inlet of the airplane wheel brake device, and an oil return port is communicated with an oil tank; the wheel speed sensor is arranged on the wheel shaft, and the signal output end of the wheel speed sensor is communicated with the speed signal acquisition port of the anti-skid brake control box through a lead. The brake command sensor is a variable gain brake command sensor and is communicated with a brake command signal receiving end of the anti-skid brake control box. The utility model discloses an anti-skidding system work number of times is few to guarantee brake efficiency, shorten the braking distance of aircraft, reduced the degree of wear of brake wheel tire, improved the life of brake wheel, tire wear is even.
Description
Technical Field
The invention relates to the field of airplane brake systems, in particular to a gain-variable digital telex anti-skid brake system and a gain-variable method.
Background
The normal braking system of the digital telex antiskid braking system of the prior art aircraft. The foot brake and the foot differential motion are generally adopted, the output brake pressure is in direct proportion to the brake footstool force, the larger the footstool force is, the longer the brake instruction sensor stroke is, the higher the brake instruction voltage is output by the brake instruction sensor, the structural schematic diagram of the brake instruction sensor in the prior art is shown in figure 1, and the brake footstool control force is in direct proportion to the brake instruction stroke. When the minimum operating force for the pilot is 980-5N, the pedal is free to travel by L 02+0.5-0.5 mm; maximum pedal stroke L when the maximum operating force for the pilot is 3800-19N132+0.5-0.5 mm; the operating force of the brake command sensor and the travel gain K of the brake command sensor1It was 9.4N/mm.
The existing airplane has larger and larger landing weight and higher braking speed, the airplane antiskid braking system simultaneously meets the requirements of normal landing braking, maximum landing braking, normal landing no-umbrella braking, maximum landing no-umbrella braking and takeoff stopping braking, the braking pressure change range meeting the braking requirement is very large by considering the moment attenuation of braking materials and the safety margin of the braking system, the rated braking pressure of the digital telex antiskid braking system in the prior art meets the braking requirement of the airplane under the most severe condition, so the rated brake pressure set by the digital fly-by-wire antiskid brake system is larger, which causes the brake pressure to be larger in the normal landing process of the airplane, when the braking torque is larger than the ground combined torque in the braking process, the anti-skidding system frequently works and releases the pressure of the braking system, so that the phenomenon of deep skidding or locking in the braking process of the airplane is eliminated, and the tire burst in the braking process is avoided. The braking efficiency of the airplane is reduced, the abrasion of the tire is increased, and the landing safety of the airplane is even affected when the tire is seriously abraded.
Through retrieval, the invention with the publication number of CN105151283A provides a control method of an airplane carbon ceramic wheel braking system with adjustable maximum braking pressure, and the invention controls the braking pressure of the carbon ceramic wheel braking system through a drag parachute signal; when the drag parachute signal is '1', the friction coefficient of the carbon-ceramic composite material brake pad is normal, and the carbon-ceramic wheel brake system brakes the airplane with rated brake pressure. When the drag parachute signal is '0', the friction coefficient of the carbon-ceramic composite material brake pad is reduced, the anti-skid control box outputs a maximum brake pressure brake instruction of the carbon-ceramic wheel brake system, the carbon-ceramic wheel brake system is multiplied by rated brake pressure according to a preset proportionality coefficient, the brake pressure is maximized, the influence of the reduction of the friction coefficient of the carbon-ceramic composite material brake pad on brake moment and brake efficiency is compensated by a method for improving the brake pressure of the carbon-ceramic wheel brake system, the problem of low brake efficiency of the carbon-ceramic wheel brake system when the landing speed of the airplane is high or the drag parachute signal is '0' is solved, and the brake efficiency and reliability of the airplane during landing are ensured. However, the invention is only suitable for the airplane with the parachute signal and has no universality for other airplanes.
Through retrieval, the invention with publication number CN105905283A proposes a braking system capable of selecting an airplane braking mode, which includes a hydraulic braking valve, a hydraulic control valve, an electro-hydraulic servo valve, a control box, and an airplane wheel speed sensor. The control box, the electro-hydraulic servo valve and the airplane wheel speed sensor form a braking anti-skid part, and a small brake device is selected through the hydraulic control valve to realize partial braking of airplane wheels of the airplane or the small brake device and a large brake device are selected to simultaneously operate to realize the total braking of the airplane wheels of the airplane. According to the invention, a hydraulic pipeline for outputting the brake system to the airplane wheel brake device is divided into a small brake device hydraulic pipeline and a large brake device hydraulic pipeline, wherein the small brake device hydraulic pipeline is kept smooth, the on-off of the large brake device hydraulic pipeline is controlled by the control device, so that the selection of an airplane brake mode is realized, the problems of large abrasion and short service life of the existing single-wheel single-brake carbon brake disc are effectively solved, and the service life and the economic benefit of the carbon disc are improved. But the invention is provided with two brake devices, which directly increases the weight of the brake system.
Disclosure of Invention
In order to overcome the defect that the structural weight of the brake system is increased in the prior art, the invention provides an electric transmission anti-skid brake system with variable gain.
The invention comprises a brake command sensor, an antiskid brake control box, an airplane wheel speed sensor, an electro-hydraulic pressure servo valve, an electromagnetic hydraulic lock, a hydraulic source, an oil tank and pedals; wherein: an oil inlet of the electromagnetic hydraulic lock is communicated with a hydraulic source, and an oil return port of the electromagnetic hydraulic lock is communicated with the oil tank; an oil outlet of the electromagnetic hydraulic lock is communicated with an oil inlet of the electro-hydraulic pressure servo valve; an oil outlet of the electro-hydraulic pressure servo valve is communicated with an oil inlet of the airplane wheel brake device, and an oil return port is communicated with an oil tank; the airplane wheel speed sensor is arranged on an airplane wheel shaft and used for detecting the speed of the airplane wheel; the signal output end of the airplane wheel speed sensor is communicated with a speed signal acquisition port of the anti-skid brake control box through a lead; and the brake pedal is fixedly connected with the movable support component of the brake command sensor.
The invention also comprises a brake command sensor; the brake command sensor is a variable gain brake command sensor.
The control signal receiving end of the electromagnetic hydraulic lock is communicated with the unlocking signal output end of the anti-skid brake control box; the control signal receiving end of the electro-hydraulic pressure servo valve is communicated with the servo valve control signal output end of the anti-skid brake control box; and a brake instruction signal receiving end of the anti-skid brake control box is communicated with a brake instruction signal output end of the brake instruction sensor.
The variable gain braking instruction sensor comprises a return spring, a return piston, a force sensing piston, an external force sensing spring and an internal force sensing spring; an inner force sensing spring is sleeved on the outer circumference of a transmission rod of the force sensing piston, and the distance L 'between the end surface of the outer end of the inner force sensing spring and the inner end surface of the clearance adjusting gasket positioned at the inner end surface of the stop sleeve is used'02+ 0.50 mm, and the distance L between the inner end surface of the inner force sensing spring and the end surface of the force sensing piston223.7+0.5-0.5 mm; an external force sensing spring is sleeved on the outer circumference of the internal force sensing spring, and the distance L between the end surface of the outer end of the external force sensing spring and the inner end surface of the gap adjusting gasket positioned at the inner end surface of the stop sleeve "02+ 0.50 mm, and during operation, the distance is the idle stroke L of the brake command sensors0。
The invention provides a variable gain digital electric transmission anti-skid brake system with a median brake pressure and a rated brake pressure on the basis of not changing the interface of the conventional brake system according to the situation of the rated brake pressure and the moment of a brake wheel matched with the rated brake pressure.
The braking instruction sensor adopted by the invention is provided with two force sensing springs in common, namely an external force sensing spring and an internal force sensing spring; the command sensor has two different operating force and travel gains; the fixed bracket component is connected with the shell through threads, and the nut and the washer play a role in fastening the fixed bracket component; there are two position sleeves in instruction sensor's the casing, the position sleeve plays the effect of location in instruction sensor's the casing, reset spring's one end and reset piston are connected, reset piston passes through screw rod and nut and the piston connection is felt to power, the piston is felt to power and the one end of external force sense spring is connected, the external force is felt the spring other end and stop sleeve UNICOM, simultaneously the spring dress is felt inside external force sense spring to internal force, the one end and the stop sleeve UNICOM of spring are felt to internal force, the other end of spring is felt to internal force is unsettled, the stop sleeve is connected to the nut, the activity bracket component is fixed through lock nut and packing ring, when the articulated fixed bracket component is fixed, when the fixed bracket component moves under the effect of force, fixed bracket component promotes reset spring and reset piston.
Experiments prove that when the pilot uses the variable gain brake command sensor with two different operating forces and travel gains, the operating force for the pilot is 980-5N at most, the idle travel L of the command sensor 02+0.5-0.5 mm; when the maximum operating force of the pilot is 1960-19N, the stroke L of the command sensor223.7+0.5-0.5mm, the commanded sensor travel increases linearly from 2+0.5-0.5mm to 23.7+0.5-0.5mm as the pilot's maneuvering force increases linearly from 980-5N to 1960-19N; operating force and travel gain K of brake command sensor24.516N/mm. The maximum operating force for the pilot is 3800-19, and the maximum travel L of the command sensor132+0.5-0.5mm, and when the pilot steering force is increased linearly from 19-6109N to 38-0109N, the command sensor stroke is increased linearly from 23.7+0-.05.5mm to 32-00.55 mm; operation of brake command sensorLongitudinal force and stroke gain K322.169N/mm.
When the operating force of a pilot is not greater than the median operating force, the stroke of the command sensor is large, the operating force is small, an external force sensing spring in the variable gain brake command sensor is compressed, and the operating force of the pilot for stepping on the pedals is in direct proportion to the brake command voltage output by the variable gain brake command sensor; when the operating force of the pilot for stepping on the pedals is larger than the median operating force and is not larger than the maximum operating force, the two force sensing springs, namely the outer force sensing spring and the inner force sensing spring, are compressed simultaneously, the operating force of the pilot is increased, and the stroke of the brake command sensor reaches the maximum. The brake command sensor outputs a brake command voltage corresponding to the stroke of the brake command sensor.
The invention ensures that the brake pressure is not more than the median brake pressure and the operating force/stroke gain K of the brake command sensor in the normal landing and braking process of the airplane24.516N/mm, the maximum operating force for the pilot is 1960-19N, and the command sensor stroke is 23.7+0.5-0.5 mm. The brake pressure is 9MPa, the brake efficiency is high, and the tire wear is uniform. When the aircraft stops taking-off brake and large-load landing brake, the brake pressure output by the pedal brake command sensor is greater than the median brake pressure and not greater than the rated brake pressure, and the operating force/stroke gain K of the brake command sensor322.169N/mm, the maximum operating force for the pilot is 38-0109, and the command sensor stroke is 32+ 0-50.5 mm. The brake pressure is 12MPa, the phenomena of locking and clamping of a brake wheel do not occur in the braking process of the airplane, and the antiskid system does not work. Meanwhile, the braking efficiency of the airplane is ensured, and the braking distance of the airplane is shortened. Therefore, the variable-gain digital telex antiskid brake system can meet the brake requirements under various conditions of normal landing brake, maximum landing brake, normal landing brake without umbrella, maximum landing brake without umbrella, takeoff stopping and the like; the anti-skid system has less working times, thereby ensuring the braking efficiency, reducing the abrasion degree of the tire of the brake wheel, prolonging the service life of the brake wheel and ensuring the uniform abrasion of the tire. The braking efficiency is ensured.
Drawings
Fig. 1 is a schematic structural view of the present invention.
Fig. 2 is a schematic structural diagram of the brake command sensor.
In the figure:
1. a brake command sensor; 2. an anti-skid brake control box; 3. an airplane wheel speed sensor; 4. an electro-hydraulic pressure servo valve; 5. an electromagnetic hydraulic lock; 6. a hydraulic source; 7. an oil tank; 8. pedaling; 9. a movable bracket assembly; 10. locking the nut; 12. a seal ring; 13. a nut; 14. a reset piston fixing nut; 15. jacking and sleeving; 16. a linear displacement sensor; 17 gap adjusting gaskets; 18. a fixed bracket assembly; 19. a housing; 20. a positioning sleeve; 21. a return spring; 22. resetting the piston; 23. a force sensing piston; 24. an external force sensing spring; 25. an internal force sensing spring; 26. a stop sleeve.
Detailed Description
The embodiment is an electric transmission anti-skid brake system with variable gain, which comprises a brake command sensor 1, an anti-skid brake control box 2, an airplane wheel speed sensor 3, an electro-hydraulic pressure servo valve 4, an electromagnetic hydraulic lock 5, a hydraulic source 6, an oil tank 7 and pedals 8.
Wherein: an oil inlet of the electromagnetic hydraulic lock 5 is communicated with a hydraulic source 6, and an oil return port is communicated with the oil tank 7; an oil outlet of the electromagnetic hydraulic lock is communicated with an oil inlet of the electro-hydraulic pressure servo valve 4; the control signal receiving end of the electromagnetic hydraulic lock is communicated with the unlocking signal output end of the antiskid brake control box 2. An oil outlet of the electro-hydraulic pressure servo valve is communicated with an oil inlet of the airplane wheel brake device, and an oil return port is communicated with an oil tank; the control signal receiving end of the electro-hydraulic pressure servo valve is communicated with the servo valve control signal output end of the antiskid brake control box 2. The wheel speed sensor 3 is arranged on a wheel shaft and used for detecting the wheel speed. The signal output end of the airplane wheel speed sensor is communicated with the speed signal acquisition port of the anti-skid brake control box 2 through a lead. And a brake instruction signal receiving end of the antiskid brake control box is communicated with a brake instruction signal output end of the brake instruction sensor 1. And the brake pedal 8 is fixedly connected with a movable bracket assembly 9 of the brake command sensor.
The brake command sensor 1 adopts a variable gain brake command sensor disclosed in application No. 201910551564.7.
The brake command sensor comprises a movable bracket component 9, a locking nut 10, a top sleeve 15, a fixed bracket component 18, a shell 19, a positioning sleeve 20, a return spring 21, a return piston 22, a force sensing piston 23, an external force sensing spring 24, an internal force sensing spring 25 and a stop sleeve 26. The present embodiment improves upon the prior art by adding an internal force sensing spring 25 to the brake command sensor. The parts of the brake command sensor are all the prior art.
One end of the shell 19 is used for placing electrical components, called an electronic cavity; the other end of the housing is used to mount mechanical components, referred to as a mechanical chamber.
A fixed bracket assembly 18 is secured by a nut at the port of the electronic cavity. The electronic cavity is divided into two chambers by the top sleeve 15, and the two chambers are communicated through a through hole in the center of the top sleeve. Two ends in the inner chamber of the two chambers are respectively provided with a positioning sleeve 20, and the outer circumferential surface of the positioning sleeve is attached to the inner surface of the inner chamber.
A stop sleeve 26 is arranged at the outer end port of the mechanical cavity through a nut 13. The force-sensing piston 23 is positioned in the mechanical cavity, and a force transmission rod of the force-sensing piston penetrates through a central hole of the stop sleeve and is positioned outside the end face of the stop sleeve; the piston end of the force sensing piston is fitted over the outer circumferential surface of the reset piston 22. The reset piston is located within the mechanical chamber and proximate to one end of the electronic chamber. Two linear displacement sensors 16 are positioned in the housing, one end of each linear displacement sensor is positioned in a central hole of the positioning sleeve 20, and the other end of each linear displacement sensor is arranged in a through hole on the end face of the reset piston 22 and is respectively fixed through a reset piston fixing nut 14. The end surface of the pressure applying rod positioned in the piston end of the force sensing piston 23 is matched with the pressure applying rod groove in the center of the outer end surface of the reset piston 22. And the two linear displacement sensors are respectively sleeved with a return spring 21. An inner force sensing spring 25 is sleeved on the outer circumference of the dowel of the force sensing piston, and an L is arranged between the end surface of the outer end of the inner force sensing spring and the inner end surface of the gap adjusting gasket 17 positioned at the inner end surface of the stop sleeve 260The inner end face of the inner force sensing spring and the force sensing piston 23Between the end faces is provided with L2The pitch of (2). An external force sensing spring 24 is sleeved on the outer circumference of the internal force sensing spring 25, and the distance between the end surface of the outer end of the external force sensing spring 24 and the inner end surface of the gap adjusting gasket 17 positioned at the inner end surface of the stop sleeve 26 is L0And the end surface of the inner end of the external force sensing spring is attached to the end surface of the force sensing piston 23.
The distance L 'between the outer end face of the internal force sensing spring and the inner end face of the gap adjusting gasket 17 located at the inner end face of the stop sleeve 26'02+ 0.50 mm, and the distance L between the end surface of the inner end of the inner force sensing spring and the end surface of the force sensing piston 23223.7+0.5-0.5 mm; the distance L between the end surface of the outer end of the external force sensing spring 24 and the inner end surface of the gap adjusting gasket 17 positioned at the inner end surface of the stop sleeve 26 "0＝2+0.5 0mm。
The distance between the end surface of the outer end of the internal force sensing spring and the inner end surface of the gap adjusting gasket 17 and the distance between the end surface of the outer end of the external force sensing spring and the inner end surface of the gap adjusting gasket are both L0When in work, the distance is the idle stroke L of the brake command sensors0。
The connecting end of the movable bracket assembly 9 is positioned in a central hole at the outer end of a dowel bar of the force sensing piston and is fastened by a locking nut 10; a universal ball bearing is arranged in a bearing hole at the bearing mounting end of the movable bracket component.
Two force sensing springs, namely an external force sensing spring 24 and an internal force sensing spring 25, are arranged in the brake command sensor; the command sensor is made to have two different operating forces and stroke gains.
Claims (3)
1. An electric transmission anti-skid brake system with variable gain comprises a brake command sensor, an anti-skid brake control box, an airplane wheel speed sensor, an electro-hydraulic pressure servo valve, an electromagnetic hydraulic lock, a hydraulic source, an oil tank and pedals; wherein: an oil inlet of the electromagnetic hydraulic lock is communicated with a hydraulic source, and an oil return port of the electromagnetic hydraulic lock is communicated with the oil tank; an oil outlet of the electromagnetic hydraulic lock is communicated with an oil inlet of the electro-hydraulic pressure servo valve; an oil outlet of the electro-hydraulic pressure servo valve is communicated with an oil inlet of the airplane wheel brake device, and an oil return port is communicated with an oil tank; the airplane wheel speed sensor is arranged on an airplane wheel shaft and used for detecting the speed of the airplane wheel; the signal output end of the airplane wheel speed sensor is communicated with a speed signal acquisition port of the anti-skid brake control box through a lead; the brake pedal is fixedly connected with the movable support assembly of the brake command sensor;
the method is characterized in that: the brake control system also comprises a brake command sensor; the control signal receiving end of the electromagnetic hydraulic lock is communicated with the unlocking signal output end of the anti-skid brake control box; the control signal receiving end of the electro-hydraulic pressure servo valve is communicated with the servo valve control signal output end of the anti-skid brake control box; and a brake instruction signal receiving end of the anti-skid brake control box is communicated with a brake instruction signal output end of the brake instruction sensor.
2. The electric brake-by-wire system according to claim 1, wherein the brake command sensor is a variable gain brake command sensor.
3. The electric antiskid braking system with variable gain of claim 2 wherein the brake command sensor with variable gain comprises a return spring, a return piston, a force sensing piston, an external force sensing spring, an internal force sensing spring; the outer circumference of the dowel bar of the force sensing piston is sleeved with an inner force sensing spring, and the distance between the end surface of the outer end of the inner force sensing spring and the inner end surface of the gap adjusting gasket positioned at the inner end surface of the stop sleeve is ensured
The distance between the inner end surface of the inner force sensing spring and the end surface of the force sensing piston
An external force sensing spring is sleeved on the outer circumference of the internal force sensing spring, and the distance between the end surface of the outer end of the external force sensing spring and the inner end surface of the gap adjusting gasket positioned at the inner end surface of the stop sleeve
When in work, the distance is the idle stroke L of the brake command sensors0。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921055891.5U CN210416963U (en) | 2019-07-08 | 2019-07-08 | Telex antiskid braking system with variable gain |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201921055891.5U CN210416963U (en) | 2019-07-08 | 2019-07-08 | Telex antiskid braking system with variable gain |
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| Publication Number | Publication Date |
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| CN210416963U true CN210416963U (en) | 2020-04-28 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201921055891.5U Active CN210416963U (en) | 2019-07-08 | 2019-07-08 | Telex antiskid braking system with variable gain |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111976960A (en) * | 2020-07-08 | 2020-11-24 | 西安航空制动科技有限公司 | Automatic flow regulator of airplane brake system |
| CN113428123A (en) * | 2021-07-15 | 2021-09-24 | 西安航空制动科技有限公司 | Tire burst prevention airplane brake system and control method thereof |
-
2019
- 2019-07-08 CN CN201921055891.5U patent/CN210416963U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111976960A (en) * | 2020-07-08 | 2020-11-24 | 西安航空制动科技有限公司 | Automatic flow regulator of airplane brake system |
| CN113428123A (en) * | 2021-07-15 | 2021-09-24 | 西安航空制动科技有限公司 | Tire burst prevention airplane brake system and control method thereof |
| CN113428123B (en) * | 2021-07-15 | 2022-10-14 | 西安航空制动科技有限公司 | Tire burst prevention airplane brake system and control method thereof |
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