阅读说明：本技术 一种飞机货舱拦阻网结构及设计方法 (Aircraft cargo hold arresting net structure and design method ) 是由 闫亚斌 陈栋梁 于静 于 2020-05-15 设计创作，主要内容包括：一种飞机货舱拦阻网结构及设计方法,该拦阻网设置在飞机货舱的前部位置,与飞机货舱壁连接,所述的拦阻网含有柔性兜网,该柔性兜网的两侧通过多个刚性承力带分别铰接在飞机货舱的加强框上。刚性承力带将大部分的拦阻载荷转化为飞机承受载荷能力较强的航向载荷传递给机身舱壁,使飞机所受的框平面内的对拉载荷大幅度降低。同时由于本申请的拦阻网的柔性兜网是一个网带长度一致的方形网,拦阻网在承载时变形量相当,其传给机身连接结构的载荷量值也基本相当,便于机身连接结构的加强设计。(The blocking net is arranged at the front part of the aircraft cargo hold and is connected with the wall of the aircraft cargo hold, the blocking net comprises a flexible net, and two sides of the flexible net are respectively hinged on a reinforcing frame of the aircraft cargo hold through a plurality of rigid bearing belts. The rigid bearing belt converts most of the blocking load into course load with stronger load bearing capacity of the airplane and transmits the course load to the cabin wall of the airplane body, so that the opposite-pulling load in the plane of the frame borne by the airplane is greatly reduced. Simultaneously because the flexible pocket net of the blocking net of this application is a guipure length unanimous square net, the deflection is equal when the blocking net bears, and its load magnitude that passes to fuselage connection structure is also equal basically, is convenient for fuselage connection structure's enhancement design.)

1. The aircraft cargo hold barrier net structure is arranged at the front part of an aircraft cargo hold and is connected with the wall of the aircraft cargo hold, and is characterized in that the barrier net comprises a flexible net, and two sides of the flexible net are respectively hinged on a reinforcing frame of the aircraft cargo hold through a plurality of rigid bearing belts.

2. The aircraft cargo hold arresting net structure as claimed in claim 1, wherein the flexible net comprises a plurality of transverse force bearing net belts and longitudinal net belts, each transverse force bearing net belt is connected with a rigid force bearing belt at its two ends, and the other ends of the rigid force bearing belts are hinged to the reinforcing frames of the aircraft cargo hold.

3. An aircraft cargo hold barrier net structure as claimed in claim 1 or claim 2 wherein the flexible net is a square net and the length of the rigid carrier strips on either side of the flexible net matches the curvature of the aircraft cargo hold reinforcing frame.

4. An aircraft cargo hold arresting net structure as claimed in claim 3 wherein the reinforcing frame of the aircraft cargo hold is provided with a plurality of parallel horizontal tie-in tabs hinged by axles to a double tab joint at the end of the rigid carrier strip.

5. An aircraft cargo hold barrier net structure as claimed in claim 4 wherein the centre of the shaft is perpendicular to the heading of the aircraft.

6. An aircraft cargo hold barrier net structure as claimed in claim 5 wherein the upper end of the flexible net is suspended by flexible straps from the top of a reinforcing frame of an aircraft cargo hold.

7. A design method of an aircraft cargo hold arresting net is characterized in that the arresting net is positioned on a reinforcing frame at the front end of an aircraft cargo hold, and the design method comprises the following steps: 1) the blocking net comprises a flexible pocket net, and two sides of the flexible pocket net are respectively hinged to a reinforcing frame of the aircraft cargo hold through a plurality of rigid bearing belts; 2) the flexible pocket net comprises a plurality of transverse bearing net belts and longitudinal dimensional net belts, two ends of each transverse bearing net belt are respectively connected with a rigid bearing belt, and the other ends of the rigid bearing belts are respectively hinged on a reinforcing frame of the aircraft cargo hold; 3) the flexible pocket net is a square net, and the length of the rigid bearing belts on the two sides of the flexible pocket net is matched with the radian of the aircraft cargo hold reinforcing frame; 4) a plurality of parallel horizontal connecting lug plates are arranged on a reinforcing frame of the aircraft cargo hold, and the connecting lug plates are hinged with double lug plate joints at the ends of the rigid force bearing belts through shafts; 5) the center of the shaft is vertical to the course of the airplane; 6) the upper end of the flexible pocket net is hung at the top of a reinforcing frame of the aircraft cargo hold through a flexible hanging strip.

8. The method of designing an aircraft cargo hold barrier net according to claim 1, wherein the stiffness of the longitudinal wife-shaped net strips and the flexible braces are designed to be less than 1/10 of the transverse messenger strips.

Technical Field

The invention belongs to the technical field of aviation, and relates to a structural design form of an aircraft cargo compartment arresting net, which is mainly used for protecting the safety of peripheral passengers of an aircraft under an emergency landing condition.

Background

According to the requirements of the CCAR25 part 561, in order to protect the safety of passengers in the emergency landing state of the airplane, the concentrated mass around the passengers must be restrained, and the restraint belongs to the restraint behavior under the large load, and imposes a more severe design requirement on the structural strength of the airplane. At present, cargo arresting systems for airplanes are mainly designed in two forms, namely arresting wall design and arresting net design. The design of the blocking wall is not adopted usually because the weight of the structure is increased more and the design difficulty of the structure of the connecting part is higher. The design and application of the arresting net mainly uses a flat net structure in the design of the existing cargo aircraft, and the structure can generate large in-plane tensile load on the plane of the arresting net when bearing cargo load. When the flat net bears the cargo load, after the flat net generates micro deformation, most of the tensile force generated by the flat net is transmitted to the fuselage joint by the transverse load, namely the load perpendicular to the course direction, and the stress result belongs to extra additional load for the aircraft structure, is not beneficial to the transmission of the load and increases the design difficulty of the aircraft structure. The design of the arresting net is less applied in the field of domestic cargo aircraft development, particularly, the data which can be used for reference and reference in the field of large-tonnage arresting design is very limited, and the technical difficulty is very high.

It is known that aircraft fuselages are relatively weak to carry tangential loads, and that when a barrier net is overloaded by the forward 9g of cargo, the in-plane loads in the plane of the mounting frame for the barrier net are very high and need to be minimised to reduce the difficulty of the fuselage structural design.

Due to the limitations of the structure and space of the airplane body, the design of the arresting net only depends on the transverse net belts for bearing, and the transverse net belts are different in length and have larger difference. Because the mesh belt is made of non-metal materials and belongs to a large deformation component, the deformation of the mesh belt is large under the action of load, so that the load difference born by the transverse mesh belts is large, and the obstruction is brought to the strengthening design of the machine body structure.

Disclosure of Invention

Aiming at the problems and requirements in the prior art, the invention aims to provide an aircraft cargo hold arresting net structure which is used for arresting cargo in an emergency state, preventing the cargo from damaging surrounding passengers, reducing the influence of arresting load on the aircraft structure, meeting the model development requirement and filling the gap of domestic arresting net development and application.

The aircraft cargo hold barrier net structure is arranged at the front part of an aircraft cargo hold and is connected with the wall of the aircraft cargo hold, and is characterized in that the barrier net comprises a flexible net, and two sides of the flexible net are respectively hinged on a reinforcing frame of the aircraft cargo hold through a plurality of rigid bearing belts.

The application also provides a design method of the aircraft cargo hold arresting net, the arresting net is positioned on the reinforcing frame at the front end of the aircraft cargo hold, and the aircraft cargo hold arresting net is characterized by comprising the following contents: 1) the blocking net comprises a flexible pocket net, and two sides of the flexible pocket net are respectively hinged to a reinforcing frame of the aircraft cargo hold through a plurality of rigid bearing belts; 2) the flexible pocket net comprises a plurality of transverse bearing net belts and longitudinal dimensional net belts, two ends of each transverse bearing net belt are respectively connected with a rigid bearing belt, and the other ends of the rigid bearing belts are respectively hinged on a reinforcing frame of the aircraft cargo hold; 3) the flexible pocket net is a square net, and the length of the rigid bearing belts on the two sides of the flexible pocket net is matched with the radian of the aircraft cargo hold reinforcing frame; 4) a plurality of parallel horizontal connecting lug plates are arranged on a reinforcing frame of the aircraft cargo hold, and the connecting lug plates are hinged with double lug plate joints at the ends of the rigid force bearing belts through shafts; 5) the center of the shaft is vertical to the course of the airplane; 6) the upper end of the flexible pocket net is hung at the top of a reinforcing frame of the aircraft cargo hold through a flexible hanging strip.

The scheme of the invention is designed and analyzed by combining the actual design of the domestic airplane structure after the foreign arresting net is designed and analyzed. Firstly, analyzing from the angle of the load borne by the airplane, the axial load bearing capacity of the fuselage structure is far greater than the capacity of bearing the load in other directions, so that the additional generated counter-pulling load in the plane of the arresting net must be reduced as much as possible; the course load applied to the aircraft by the arresting net is increased as much as possible.

Because of the limitation of the cross section shape of the machine body, the initial lengths of all transverse main bearing net belts formed by the blocking nets are different, and the flexible pocket nets belong to non-metallic materials and are greatly deformed in a stressed state, so that the loads on all the transverse bearing net belts are different, and great difficulty is caused in the strengthening design of the machine body structure. Through research, the transverse force bearing net belt of the blocking net is designed into two parts, the middle part is made of flexible materials, the two sides of the transverse force bearing net belt are connected with the reinforcing frame to form a rigid force bearing belt, and the rigid force bearing belt is made of metal materials, so that deformation of the rigid force bearing belt in a loaded state is reduced. Under the loading state of the arresting net, the design can ensure that the load magnitude on each transverse main bearing net belt is basically equivalent, and is convenient for the design of a connecting structure of the machine body.

The invention has the advantages that: 1) according to the large-tonnage arresting net designed according to the scheme of the invention, the arresting load is transmitted to the reinforcing frame through the rigid bearing belt, because the rigid bearing belt and the reinforcing frame are in a hinged relation, the rigid bearing belt deviates from the plane where the reinforcing frame is located along with the increase of the arresting load, the included angle between the rigid bearing belt and the wall of the aircraft cabin is reduced, and the rigid bearing belt converts most of the arresting load into course load with stronger load bearing capacity of the aircraft and transmits the course load to the wall of the aircraft cabin, so that the counter-pulling load in the plane of the frame borne by the aircraft is greatly reduced. 2) Simultaneously because the flexible pocket net of the blocking net of this application is a guipure length unanimous square net, the deflection is equal when the blocking net bears, and its load magnitude that passes to fuselage connection structure is also equal basically, is convenient for fuselage connection structure's enhancement design.

The present application will be described in further detail with reference to the accompanying drawings.

Drawings

Fig. 1 is a schematic view of an aircraft cargo hold barrier net.

Fig. 2 is a schematic connection diagram of a transverse force-bearing net belt, a rigid force-bearing belt and a reinforcing frame.

Fig. 3 is a schematic view of an aircraft cargo hold arresting net in an arresting state.

The numbering in the figures illustrates: the cargo-carrying device comprises a reinforcing frame 1, a flexible pocket net 2, a rigid bearing belt 3, a transverse bearing net belt 4, a longitudinal dimensional net belt 5, a flexible hanging belt 6, a shaft 7, a horizontal connecting lug 8, a double lug joint 9, a fuselage bulkhead 10, a cargo hold 11 and cargo loads 12.

Detailed Description

Referring to the drawings, the aircraft cargo hold barrier net structure of the present application is provided at a forward location in an aircraft cargo hold 11 and is connected to an aircraft cargo hold wall 10, and in order to reduce the in-plane tensile loads in the plane of the barrier net mounting frame, the barrier net is in the form of a flexible tuck net design. The flexible pocket net 2 of the arresting net in implementation comprises a plurality of transverse bearing net belts 4 and longitudinal dimensional net belts 5, two ends of each transverse bearing net belt 4 are respectively connected with a rigid bearing belt 3, and the other ends of the rigid bearing belts are respectively hinged on a reinforcing frame of an airplane cargo hold through shafts 7. The rigid force bearing belts 3 are respectively arranged at two sides of the flexible pocket net 2 and are respectively hinged on the reinforcing frame 1 of the aircraft cargo hold 11.

It is emphasized that the center of the articulated shaft 7 between the rigid bearing belt 3 and the reinforcing frame is vertical to the course of the airplane, so that when the arresting net is in an arresting state, under the action of an arresting load, the rigid bearing belt is far away from the frame plane of the reinforcing frame for mounting the arresting net around the shaft 7, and the direction of the rigid bearing belt 3 is close to the course of the airplane, so that the rigid bearing belt 3 converts the arresting load into a course load with stronger load bearing capacity of the airplane and transmits the course load to the cabin wall of the airplane body.

In the implementation, the flexible pocket net 2 is preferably a square net, and the length of the rigid bearing belt 3 on two sides of the flexible pocket net 2 is matched with the radian of the aircraft cargo hold reinforcing frame 1.

In order to balance the stress of the reinforcing frame, a plurality of parallel horizontal connecting lug plates are arranged on the reinforcing frame of the aircraft cargo hold, and the connecting lug plates are hinged with double lug plate joints at the ends of the rigid bearing belt through shafts.

In order to balance the stress of the barrier net and keep the unfolding state of the barrier net, the upper end of the flexible net 2 is hung on the top of a reinforcing frame 1 of an aircraft cargo hold through a flexible hanging strip 6.

In implementation, two ends of the transverse bearing net belt 4 can be respectively connected with the rigid bearing belt through the hooks and the hanging rings, and the double lug plate joint 9 at the other end of the rigid bearing belt is connected with the horizontal connecting lug plate 8 of the cargo compartment reinforcing frame by adopting a shaft-shaped pin or a bolt.

In practice, the size of the net grid is such that it will restrain box cargo of 250mm x 300mm size, i.e. the box cargo will not fall out of the grid when loaded. Therefore, after the number of the transverse bearing net belts is determined, a certain number of transverse and longitudinal net belts for dimensional shape are required to be arranged. And because the design shape of the blocking net is a pocket-shaped blocking net, in order to keep the initial shape of the blocking net during installation, two hanging points are added on the uppermost transverse force bearing net belt in the plane of the blocking net, and the blocking net is hung on the top of a reinforcing frame 1 of an aircraft cargo hold through two flexible hanging strips 6. In order to ensure that the auxiliary mesh belts for dimensional shapes comprise the transverse dimensional mesh belts, the longitudinal dimensional mesh belts and the flexible hanging strips and do not participate in overall bearing so as to protect the rest structures of the airplane from being damaged, the rigidity of the auxiliary mesh belts for dimensional shapes is designed to be smaller than 1/10 of the transverse bearing mesh belts, and particularly the longitudinal dimensional mesh belts and the flexible hanging strips can be automatically disconnected from the airplane structure as the auxiliary mesh belts at the initial stage of bearing load of the arresting net.