Main landing gear of ultra-light aircraft

Abstract

A main landing gear of an ultra-light aircraft comprises an elastic plate and a landing wheel. The two ends of the elastic plate are straight plate sections, the middle of the elastic plate is a bent plate section, one straight plate section is used for being connected with a fuselage of an airplane, and the other straight plate section is used for being connected with a landing wheel. In a natural state, the included angle between the two straight plate sections is larger than 65 degrees and smaller than 90 degrees. The elastic plate of the main landing gear is formed by hot bending of the long-strip-shaped spring steel plate, has the advantages of being simple in structure, light in weight and easy to maintain, and meets the design requirements of ultra-light aircrafts; the main landing gear has good grounding toughness, the impact force generated when an aircraft lands is buffered through deformation of the elastic plates, and soft landing is achieved; the main landing gear has good safety, and can prevent the landing wheel from falling laterally due to excessive deflection.

Description

Technical Field

[0001] The utility model relates to the technical field of ultra-light aircraft, in particular to a main landing gear of an ultra-light aircraft. Background Art

[0002] With the liberalization of low-altitude control by the state, ultra-light aircraft have come into the public view. Ultra-light aircraft are characterized by small size, light weight, simple structure, easy operation, short take-off distance, and low requirements for take-off sites.

[0003] An aircraft has a nose landing gear and two main landing gears. In order to meet the design requirements of light weight and simple structure, current light aircraft and ultra-light aircraft usually adopt non-retractable landing gears. However, most of the main landing gears of aircraft still adopt complex hydraulic shock absorption or gas-liquid shock absorption structures. From the perspectives of weight, structure, and maintenance, the current nose landing gear still fails to meet the design requirements of light weight, simple structure, and easy maintenance.

[0004] In addition, ultra-light aircraft have low requirements for take-off sites, which requires the main landing gear to have better grounding toughness and safety. Summary of the Utility Model

[0005] In order to overcome the deficiencies in the background art, the utility model discloses a main landing gear of an ultra-light aircraft, and its purposes are:

[0006] 1. Meet the design requirements of light weight, simple structure, and easy maintenance;

[0007] 2. Enable the main landing gear to have better grounding toughness and safety.

[0008] Specifically, the utility model adopts the following technical solutions:

[0009] A main landing gear of an ultra-light aircraft includes an elastic plate member and a landing wheel; both ends of the elastic plate member are straight plate segments, and the middle is a bent plate segment. One of the straight plate segments is used to connect the fuselage of the aircraft, and the other straight plate segment is used to connect the landing wheel; in the natural state, the included angle between the two straight plate segments is greater than 65° and less than 90°.

[0010] Further improving the technical solution, the elastic plate member is formed by hot bending a long strip of spring steel plate.

[0011] Further improving the technical solution, the width of the long strip of spring steel plate is 40 - 70 mm, and the thickness is 10 - 15 mm.

[0012] Further improving the technical solution, the radius of the bent plate segment is 350 - 400 mm.

[0013] Further improving the technical solution, the crown of the landing wheel tire is circular.

[0014] Further improve the technical solution. The straight plate section connected to the fuselage is provided with a plurality of connection holes, and the straight plate section is connected to the rib plate on the fuselage through bolts.

[0015] Further improve the technical solution. The straight plate section connected to the landing wheel is provided with a plurality of connection holes, and the straight plate section is connected to the axle of the landing wheel through bolts.

[0016] Further improve the technical solution. A brake disc is installed on the axle.

[0017] Further improve the technical solution. The ultra-light aircraft has a pair of main landing gears arranged oppositely, and a steel wire rope is fixed between two elastic plate members; when the aircraft takes off or lands, the steel wire rope is in a taut state, preventing the elastic plate members from continuing to deform outward; after the aircraft takes off, the elastic plate members rebound inward, and the steel wire rope is in a relaxed state.

[0018] Further improve the technical solution. A tension spring is arranged between the steel wire rope and the fuselage. When the steel wire rope is in a relaxed state, the tension spring pulls up the steel wire rope.

[0019] After implementing the above technical solutions, compared with the background technology, the beneficial effects of the present utility model are as follows:

[0020] 1. The structure of this main landing gear is simple, lightweight, and easy to maintain, meeting the design requirements of ultra-light aircraft;

[0021] 2. This main landing gear has good grounding toughness, buffers the impact force during aircraft landing through the deformation of elastic plate members, and realizes soft landing;

[0022] 3. This main landing gear has good safety, and can prevent the landing wheel from tipping over due to excessive skew. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG. Figure 1 shows the structural schematic diagram of the main landing gear during landing in Embodiment 1.

[0024] FIG. Figure 2 shows the structural schematic diagram of the elastic plate member.

[0025] FIG. Figure 3 shows the structural schematic diagram of the main landing gear during flight in Embodiment 1.

[0026] FIG. Figure 4 shows the structural schematic diagram of the main landing gear in Embodiment 2.

[0027] FIG. Figure 5 shows the structural schematic diagram of the main landing gear in Embodiment 3.

[0028] In the drawings:

[0029] 10. Fuselage

[0030] 20. Elastic plate; 21. Straight plate section at the fuselage end; 22. Bent plate section; 23. Straight plate section at the landing wheel end

[0031] 30. Landing wheel

[0032] 40. Brake disc

[0033] 50. Steel wire rope

[0034] 60. Tension spring Detailed implementation manners

[0035] The preferred implementation manners of the present utility model will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the present utility model and are not intended to limit the protection scope of the present utility model. It should be noted that in the description of the present utility model, the terms indicating directions or positional relationships such as "front", "rear", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the accompanying drawings. This is only for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation to the present utility model. It should also be noted that in the description of the present utility model, unless otherwise clearly specified and limited, the terms "installation", "connection", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0036] Embodiment 1:

[0037] Refer to the attached Figure 1 A super-light aircraft has a pair of non-retractable main landing gears, which mainly consist of an elastic plate 20 and a landing wheel 30. The structure and functions will be specifically described below.

[0038] Refer to the attached Figure 1 and the attached Figure 2。The elastic plate member 20 is formed by hot bending a long strip of spring steel plate and has a certain elasticity. Specifically, both ends of the elastic plate member 20 are straight plate segments, and the middle is a bent plate segment 22. Among them, the straight plate segment in the horizontal state is the fuselage end straight plate segment 21, on which there are four connection holes and is connected to the rib plate of the aircraft fuselage 10 through bolts. The other straight plate segment is the landing wheel end straight plate segment 23, on which there are also four connection holes and is connected to the axle of the landing wheel 30 through bolts.

[0039] By attaching Figure 1 and attaching Figure 2 It can be seen that this main landing gear does not adopt a hydraulic shock absorption or gas-liquid shock absorption structure, but uses the elastic plate member 20 as a buffer during aircraft landing. From the perspectives of weight, structure, and maintenance, the elastic plate member 20 has the advantages of light weight, simple structure, and easy maintenance, meeting the design requirements of ultra-light aircraft.

[0040] Preferably, the width of the spring steel plate is 40 - 70 mm, the thickness is 10 - 15 mm, and the radius of the bent plate segment 22 is 350 - 400 mm. In the natural state, the included angle between the fuselage end straight plate segment 21 and the landing wheel end straight plate segment 23 is greater than 65° and less than 90°. If the included angle is too small, the landing wheel 30 will deviate severely outward, and the landing wheel 30 will fall outward when the aircraft lands. If the included angle is greater than 90°, when the aircraft lands, the strong impact force will cause the landing wheel 30 to fall inward.

[0041] In this embodiment, the material of the spring steel plate is selected as 65Mn and is tempered at medium temperature after hot bending. According to the weight of the ultra-light aircraft and the impact force during landing, various parameters of the elastic plate member 20 are calculated and designed. Specifically, the width of the spring steel plate is 50 mm, the thickness is 12 mm, the radius of the bent plate segment 22 is 388 mm, and the included angle between the fuselage end straight plate segment 21 and the landing wheel end straight plate segment 23 is 83°.

[0042] Referring to the attachment Figure 3 。After the aircraft takes off, the elastic plate member 20 only bears the weight of the landing wheel 30, and at this time, a pair of elastic plate members 20 bend inward.

[0043] Referring to the attachment again Figure 1 。When the aircraft lands, the ground exerts an upward impact force on the elastic plate member 20 through the landing wheel 30. At this time, a pair of elastic plate members 20 begin to bend outward, and the included angle between the fuselage end straight plate segment 21 and the landing wheel end straight plate segment 23 becomes larger, approaching or slightly exceeding 90°. The process of the elastic plate member 20 deforming is also a process of buffering the aircraft landing, which can enable the aircraft to achieve a soft landing and reduce the damage caused by the landing impact to the aircraft.

[0044] During the aircraft landing process, the landing gear 30 has a lateral sliding process (the contact point between the tire and the ground has a process of changing from the inside to the outside), which will seriously wear the tread of the tire. Therefore, it is preferable to use a tire with a circular tread. The tire with a circular tread can reduce the wear caused by lateral sliding to the tread.

[0045] A brake disc 40 is installed on the wheel axle. The function of the brake disc 40 is to brake the landing gear 30 to decelerate the aircraft.

[0046] Embodiment 2:

[0047] In Embodiment 1, during landing, the influence of the aircraft's load on the elastic plate 20 is very large. When the load exceeds the limit, the landing gear 30 may fall inward due to excessive deformation. In addition, improper landing operations (such as too fast deceleration) will also cause the landing gear 30 to fall inward.

[0048] Refer to the appendix Figure 4 What is different from Embodiment 1 in this embodiment is that a steel wire rope 50 is fixed between the two elastic plates 20.

[0049] When the aircraft takes off or lands, the steel wire rope 50 is in a taut state, preventing the elastic plate 20 from continuing to deform outward. At this time, it can prevent the landing gear 30 from falling inward due to excessive deformation. In this way, it can ensure that the elastic plate 20 has sufficient deformation to enable the aircraft to land softly, and can also prevent the landing gear 30 from falling sideways due to excessive skewing.

[0050] After the aircraft takes off, the elastic plate 20 rebounds inward, and at this time the steel wire rope 50 is in a relaxed state.

[0051] Of course, a rigid rod can also be fixed between the two elastic plates 20. However, under the constraint of the rigid rod, the deformation of the elastic plate 20 is small and cannot play an adequate buffering role, and the aircraft will experience a hard landing.

[0052] Embodiment 3:

[0053] In Embodiment 2, before the aircraft lands, the steel wire rope 50 is in a hanging state, and at this time the steel wire rope 50 may catch an object on the ground and cause an accident.

[0054] Refer to the appendix Figure 5 What is different from Embodiment 2 in this embodiment is that a tension spring 60 with a relatively small rigidity is provided between the steel wire rope 50 and the fuselage 10. When the steel wire rope 50 is in a relaxed state, the tension spring 60 pulls up the steel wire rope 50 to prevent the steel wire rope 50 from catching an object on the ground. When the aircraft takes off or lands, the tension of the tension spring 60 is small and will not affect the tautness of the steel wire rope 50.

[0055] The parts not described in detail are prior arts. Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present utility model. The protection scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. The main landing gear of an ultra-light aircraft, characterized in that: It includes an elastic plate member and a landing wheel; both ends of the elastic plate member are straight plate segments, and the middle is a bent plate segment. One of the straight plate segments is used to connect the fuselage of the aircraft, and the other straight plate segment is used to connect the landing wheel; in the natural state, the included angle between the two straight plate segments is greater than 65° and less than 90°; the ultra-light aircraft has a pair of main landing gears arranged oppositely, and a steel wire rope is fixed between the two elastic plate members; when the aircraft takes off or lands, the steel wire rope is in a taut state, preventing the elastic plate member from continuing to deform outward; after the aircraft takes off, the elastic plate member rebounds inward, and the steel wire rope is in a relaxed state.

2. The main landing gear of an ultra-light aircraft according to claim 1, characterized in that: The elastic plate member is formed by hot bending a long strip of spring steel plate.

3. The main landing gear of a super-light aircraft according to claim 2, characterized in that: The width of the long strip of spring steel plate is 40 - 70 mm, and the thickness is 10 - 15 mm.

4. The main landing gear of an ultra-light aircraft as claimed in claim 3, characterized in that: The radius of the bent plate segment is 350 - 400 mm.

5. The main landing gear of an ultra-light aircraft as claimed in claim 1, wherein: The crown of the landing wheel tire is circular.

6. The main landing gear of an ultra-light aircraft as claimed in claim 1, characterized in that: The straight plate segment connected to the fuselage is provided with a plurality of connection holes, and this straight plate segment is connected to the rib plate on the fuselage through bolts.

7. The main landing gear of an ultra-light aircraft according to claim 1, characterized in that: The straight plate segment connected to the landing wheel is provided with a plurality of connection holes, and this straight plate segment is connected to the axle of the landing wheel through bolts.

8. The main landing gear of a super-light aircraft according to claim 7, characterized in that: A brake disc is installed on the axle.

9. The main landing gear of an ultra-light aircraft according to claim 1, characterized in that: A tension spring is arranged between the steel wire rope and the fuselage. When the steel wire rope is in a relaxed state, the tension spring pulls up the steel wire rope.

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