CN218288104U - Landing gear for aircraft - Google Patents

Abstract

The present application provides a landing gear for an aircraft. The aircraft includes a fuselage, and the landing gear includes a pair of landing gears configured for symmetrical arrangement about a plane of symmetry of the fuselage. Each landing gear of a pair of landing gears includes: a first leg including a first end connected to the fuselage and a second end opposite the first end; a second leg including a third end connected to the fuselage and a fourth end opposite the third end; and the middle section is connected between the second end and the fourth end and comprises a first section connected with the second end, a second section connected with the fourth end and a bending section connected with the first section and the second section. The bend section is configured to bend toward the fuselage such that when the aircraft rests on a flat base surface, the first section and the second section contact the base surface, while the bend section does not contact the base surface. The landing gear according to the application can buffer impact, reduce manufacturing materials and reduce the weight of an aircraft.

Description

Landing gear for aircraft

The application is a divisional application of the Chinese utility model patent application with the application number of 202221909098.9 filed on 21/7/2022.

Technical Field

The present application relates to the field of aircraft, and in particular to a landing gear for an aircraft.

Background

Urban Air Mobility (UAM) is an emerging mode of transportation that primarily involves intra-urban or inter-urban short haul transportation. UAM vehicles typically fly in low-altitude (100 meters to 1000 meters) or ultra-low-altitude (below 100 meters) airspace.

A Vertical Take-off and Landing (VTOL) aircraft is a common UAM vehicle. In the UAM scene, the vertical take-off and landing aircraft is expected to meet the requirement of small size due to the limitation of urban buildings, plants, road traffic, crowds and other factors. Meanwhile, in order to improve the transportation efficiency, the vertical take-off and landing aircraft is expected to meet the requirement of high load. However, it is difficult to meet the requirements of small size and high load for all the existing vertical take-off and landing aircrafts.

Therefore, a new type of VTOL aerial vehicle is needed.

SUMMERY OF THE UTILITY MODEL

In view of the above, the present application proposes a novel vertical take-off and landing aircraft to solve the problems described in the background art.

According to one aspect of the present application, there is provided a vertical take-off and landing aircraft comprising: a fuselage including a nose, a tail, and a midsection extending between the nose and the tail, a nose profile of the nose configured to be symmetrical about a plane of symmetry of the VTOL aerial vehicle and diverging from a leading edge point of the nose to the midsection, the nose profile divided by a horizontal plane passing through the leading edge point and perpendicular to the plane of symmetry into an upper surface and a lower surface, the lower surface projecting downwardly relative to the horizontal plane to a greater extent than the upper surface projecting upwardly relative to the horizontal plane when the nose profile diverges from the leading edge point to the midsection; and a pair of front wings connected to the nose and a pair of rear wings connected to the tail, the pair of front wings and the pair of rear wings being arranged in a tandem wing arrangement, the pair of front wings being arranged on the nose in a position adjacent to the horizontal plane in a vertical direction perpendicular to the horizontal plane.

In some embodiments, the horizontal plane and the machine head profile intersect at a left boundary and a right boundary, the left boundary and the machine body middle section intersect at a first left end point, the right boundary and the machine body middle section intersect at a first right end point, the symmetry plane and the machine head profile intersect at an upper contour line and a lower contour line, the upper contour line and the machine body middle section intersect at an upper end point, the lower contour line and the machine body middle section intersect at a lower end point, a centroid of a cross-sectional shape of the machine head profile, which is intercepted by the symmetry plane, is located on a side of a projection of the left boundary on the symmetry plane, which is close to the lower end point, and is located on a side of a perpendicular bisector of the projection, which is close to the leading edge point.

In some embodiments, the spacing in the vertical direction between the upper endpoint and the lower endpoint defines a height of the head, the height of the head is H, the spacing in the vertical direction between the leading edge point and the upper endpoint is H1, H1 is in the range of 0 to 0.3H, the spacing in the vertical direction between the leading edge point and the lower endpoint is H2, and H2 is in the range of 0.7H to H.

In some embodiments, H1 is in the range of 0.1H to 0.2H, and H2 is in the range of 0.8H to 0.9H.

In some embodiments, the upper contour line is an upward curve with gradually increasing height in a direction from the leading edge point to the upper end point, and the lower contour line is a downward curve with gradually decreasing height in a direction from the leading edge point to the lower end point.

In some embodiments, the upper surface and the lower surface are each a continuous curved surface diverging from a leading edge point of the nose to the midsection of the fuselage.

In some embodiments, the upper contour line and the lower contour line define a boundary of a projected shape of the handpiece profile on the plane of symmetry.

In some embodiments, the arrangement position of the front wing on the head is closer to the upper end point than the lower end point in the vertical direction.

In some embodiments, a spacing between an arrangement position of the front wing on the head and the upper end point in the vertical direction is in a range of 0 to 0.3H.

In some embodiments, an arrangement position of the front wing on the nose is higher than an arrangement position of the rear wing on the tail in the vertical direction.

In some embodiments, the front wing is disposed on the head at a position closer to the leading edge point than the first left end point in a front-to-back direction parallel to the plane of symmetry and parallel to the horizontal plane.

In some embodiments, a spacing in the fore-aft direction between the leading edge point and the first left end point defines a length of the head, the length of the head is L, L is in a range of H to 1.5H, and a spacing in the fore-aft direction between the arrangement position and the leading edge point is in a range of 0 to 0.3L.

In some embodiments, the contour of the projection of the head on the horizontal plane includes a left contour line and a right contour line respectively extending from the leading edge point to the mid-section of the body, the left contour line and the right contour line being symmetrical about the plane of symmetry and intersecting the mid-section of the body at a second left end point and a second right end point respectively, the second left end point being no higher than the first left end point in the vertical direction, and a spacing between the second left end point and the first left end point in the vertical direction being H3, H3 being in a range of 0 to 0.4H.

In some embodiments, a spacing between the second left end point and the second right end point in a lateral direction perpendicular to the plane of symmetry defines a width of the head, the width of the head being W, W being in a range of H to 1.5H.

In some embodiments, the mid-fuselage section and the tail are tadpole-shaped or truncated cone-shaped in profile.

In some embodiments, the pair of front wings and the pair of rear wings are in an X-shaped layout with forward wing sweep and rear wing sweep, the forward wing area of the pair of front wings being smaller than the rear wing area of the pair of rear wings.

In some embodiments, the forward wing area is 50% to 80% of the aft wing area.

In some embodiments, the leading edge forward sweep angle of the forward wing and the leading edge aft sweep angle of the aft wing each do not exceed 25 °.

In some embodiments, each of the pair of front wings includes a front wing tip, a leading edge of the front wing tip being more forward than the leading edge point in a fore-aft direction parallel to the plane of symmetry and parallel to the horizontal plane.

In some embodiments, the pair of front wings have a shorter span than the pair of rear wings, each front wing of the pair of front wings comprising a front wing tip, a front wing root, and a front wing body extending between the front wing tip and the front wing root, each rear wing of the pair of rear wings comprising a rear wing tip, a rear wing root, and a rear wing body extending between the rear wing tip and the rear wing root, the VTOL aircraft further comprising a pair of elongated links arranged symmetrically about the plane of symmetry, each elongated link of the pair of elongated links extending substantially parallel to the plane of symmetry, connected to a respective one of the front wings at the front wing tip of the respective one of the pair of front wings and connected to a respective one of the rear wings at the rear wing body of the respective one of the pair of rear wings corresponding to the respective one of the front wings, the VTOL comprising a plurality of rotors symmetrically arranged about the plane of symmetry on the links and configured for providing vertical power takeoff to the aircraft.

In some embodiments, the plurality of rotors includes at least six rotors.

In some embodiments, the link comprises an intermediate section between the front wing tip and the rear wing body, a forward section extending from the intermediate section beyond the front wing tip, and a rearward section extending from the intermediate section beyond the rear wing body, with rotors disposed on the intermediate section, the forward section, and the rearward section.

In some embodiments, the axis of rotation of each rotor of the plurality of rotors is oriented perpendicular to the horizontal plane.

In some embodiments, the plurality of rotors are disposed on a side of the link facing away from the horizontal plane.

In some embodiments, the rotor includes a blade and a coupling mechanism rotatably coupling the blade to the link, at least the blade of the rotor being positioned higher than the fuselage in the vertical direction.

In some embodiments, each of the pair of rear wings includes a rear wing tip at which is disposed a vertical tail wing including a fixed vertical stabilizer and a rudder operable to steer heading.

In some embodiments, the vtol aerial vehicle comprises a pair of horizontal thrusters symmetrically arranged about the plane of symmetry and configured for providing horizontal power to the vtol aerial vehicle, each horizontal thruster of the pair of horizontal thrusters being connected to a respective one of the pair of rear wings at a leading edge or a trailing edge thereof, proximate to a rear wing root of the respective one of the pair of rear wings, the pair of horizontal thrusters being a pair of ducted fans or a pair of propellers.

In some embodiments, the VTOL aerial vehicle further comprises a pair of landing gears symmetrically arranged about the plane of symmetry. Each landing gear of the pair of landing gears includes: a first leg including a first end connected to the fuselage and a second end opposite the first end; a second leg including a third end connected to the fuselage and a fourth end opposite the third end; and a mid-section connected between the second end and the fourth end, the mid-section including a first section connected the second end, a second section connected the fourth end, and a bending section connected the first section and the second section, the bending section configured to bend towards the fuselage such that when the vtol aircraft is parked on a flat base surface, the first section and the second section contact the base surface, and the bending section does not contact the base surface.

In some embodiments, the first and second sections are elongate and the first and second sections are collinear.

In some embodiments, the first section and the second section are each oriented along a front-to-back direction parallel to the plane of symmetry and parallel to the horizontal plane.

In some embodiments, the cross-section of the first leg taken in a plane parallel to the horizontal plane is each drop-shaped in profile to reduce drag.

In some embodiments, the cross-section of the second leg taken in a plane parallel to the horizontal plane is each drop-shaped in profile to reduce drag.

In some embodiments, the first leg is elongate and makes an angle of 45 ° to 135 ° with the first section.

In some embodiments, the second leg is elongate and makes an angle of 45 ° to 135 ° with the second section.

In some embodiments, the first leg, the second leg, the first section, and the second section are coplanar in a first plane, the first plane being inclined relative to the plane of symmetry, the bend section being offset relative to the first plane in a direction away from the plane of symmetry.

In some embodiments, the bend section is parallel to the plane of symmetry.

In some embodiments, the bend segment includes a first portion connecting the first segment, a second portion connecting the second segment, and a third portion connecting the first portion and the second portion, the third portion being parallel to the first segment and the second segment.

According to another aspect of the present application, there is provided a landing gear for an aircraft, the aircraft comprising a fuselage, characterized in that the landing gear comprises a pair of landing gears configured to be arranged symmetrically about a plane of symmetry of the fuselage, each landing gear of the pair of landing gears comprising: a first leg including a first end connected to the fuselage and a second end opposite the first end; a second leg including a third end connected to the fuselage and a fourth end opposite the third end; and a mid-section connected between the second end and the fourth end, the mid-section including a first section connected the second end, a second section connected the fourth end, and a bending section connecting the first section and the second section, the bending section configured to bend towards the fuselage such that when the aircraft is parked on a flat datum, the first section and the second section contact the datum, and the bending section does not contact the datum.

In some embodiments, the first and second sections are elongate and the first and second sections are collinear.

In some embodiments, the first section and the second section are each oriented along a direction parallel to the plane of symmetry and parallel to a plane perpendicular to the plane of symmetry.

In some embodiments, the cross-section of the first leg taken in a plane perpendicular to the plane of symmetry is drop-shaped in profile to reduce drag.

In some embodiments, the cross-section of the second leg taken in a plane perpendicular to the plane of symmetry is drop-shaped in profile to reduce drag.

In some embodiments, the first leg is elongate and makes an angle of 45 ° to 135 ° with the first section.

In some embodiments, the second leg is elongate and makes an angle of 45 ° to 135 ° with the second section.

In some embodiments, the first leg, the second leg, the first section and the second section are coplanar to a first plane, the first plane being inclined relative to the plane of symmetry, the bend section being offset relative to the first plane in a direction away from the plane of symmetry.

In some embodiments, the bend section is parallel to the plane of symmetry.

In some embodiments, the first plane is at an angle of between 0 ° and 50 ° to the plane of symmetry. Preferably, the included angle is 40 °.

In some embodiments, the bend segment includes a first portion connecting the first segment, a second portion connecting the second segment, and a third portion connecting the first portion and the second portion, the third portion being parallel to the first segment and the second segment.

The vertical take-off and landing aircraft can meet the requirements of small size and high load by utilizing the combination of the lower convex type aircraft nose profile and the tandem wing layout, and is particularly suitable for urban air traffic scenes.

Drawings

The above-described and other aspects of the present application will be more fully understood and appreciated in view of the accompanying drawings. It should be noted that the figures are merely schematic and are not drawn to scale. In the drawings:

FIG. 1 schematically illustrates a perspective view of a VTOL aerial vehicle according to a preferred embodiment of the present application;

FIG. 2 schematically illustrates another perspective view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 3 schematically illustrates a side view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 4 schematically illustrates a front view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 5 schematically illustrates a rear view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 6 schematically illustrates a top view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 7 schematically illustrates a bottom view of the VTOL aerial vehicle shown in FIG. 1;

FIG. 8 schematically illustrates a nose profile of a nose of the VTOL aerial vehicle shown in FIG. 1;

FIG. 9 schematically illustrates a cross-sectional profile of the fuselage of the VTOL aircraft shown in FIG. 1 taken through the plane of symmetry;

FIG. 10 schematically illustrates a cross-sectional profile of a nose of the VTOL aerial vehicle shown in FIG. 1 taken along line I-I of FIG. 6; and

FIG. 11 schematically illustrates a cross-sectional profile of a left landing gear of the VTOL aircraft shown in FIG. 1, taken along line II-II of FIG. 3.

Detailed Description

Specific embodiments of the present application are described in detail below with reference to examples. It should be understood that these exemplary embodiments are not meant to limit the present application in any way. Furthermore, the features in the embodiments of the present application may be combined with each other without conflict. In the different figures, identical components are denoted by identical reference numerals and, for the sake of brevity, other components are omitted, but this does not indicate that the vtol aircraft of the present application may not include other components. Moreover, for the sake of brevity, all of the components of the VTOL aerial vehicle are not depicted in the figures and are described below. It should also be understood that the dimensions, proportions and numbers of elements in the figures are not intended to limit the present application.

Fig. 1 to 7 depict a vertical take-off and landing aircraft 1 according to a preferred embodiment of the present application. The VTOL aerial vehicle 1 may be used as a UAM vehicle for carrying people or cargo. The vtol aerial vehicle 1 comprises a fuselage 3, which fuselage 3 comprises a nose 5, a tail 7 and a midship 9 extending between the nose 5 and the tail 7. Furthermore, as will be described later, the vertical take-off and landing aircraft 1 further includes a vertical propulsion device and a horizontal propulsion device for powering the vertical take-off and landing aircraft 1. Specifically, the vertical propulsion device is configured to provide vertical power to the vertical take-off and landing aircraft 1, and the horizontal propulsion device is configured to provide horizontal power to the vertical take-off and landing aircraft 1. It should be understood that the vertical and horizontal pushers may be any suitable type of pushers in the art, and may be the same or different pushers. For example, the vertical propulsion means and the horizontal propulsion means may be provided by the same tiltrotor system. Under the condition that the vertical take-off and landing aircraft 1 is provided with two sets of power systems, namely a vertical propelling device and a horizontal propelling device, the two sets of power systems are mutually supplemented, so that the safety and the reliability of the vertical take-off and landing aircraft 1 can be improved.

As shown in fig. 4 to 7, the nose profile of the nose 5 is configured to be symmetrical about the plane of symmetry a of the vtol aircraft 1 and to diverge from the leading edge point P1 of the nose 5 to the midship 9. As used in this application, the plane of symmetry a of the vtol aerial vehicle 1 refers to an imaginary plane that divides the vtol aerial vehicle 1 into two halves that are substantially mirror images of each other. It should be understood, however, that this does not mean that the vtol aircraft 1 of the present application is limited to being completely symmetrical about the plane of symmetry a. For example, the VTOL aerial vehicle 1 may have certain components or parts on one side of the plane of symmetry A and no such components or parts on the other side. Further, as used in the present application, the leading edge point P1 of the nose 5 refers to the most forward point or portion (which may be approximated as one imaginary point) of the nose 5 in the direction of movement (i.e., the fore-and-aft direction) of the VTOL aerial vehicle 1. Thus, the leading edge point P1 of the head 5 is on the symmetry plane a. In other words, the symmetry plane a passes through the leading point P1 of the head 5. Further, as used herein, an "outline" is a peripheral definition that constitutes, defines, or is representative of the peripheral edge of a figure or object, and represents the overall outline of the figure or object.

With continued reference to fig. 1-4, the nose profile of the nose 5 is divided by a horizontal plane B passing through the leading point P1 and perpendicular to the plane of symmetry a into an upper surface 51 and a lower surface 53. Horizontal plane B is also an imaginary plane. As best shown in fig. 1-3, the lower surface 53 of the nose 5 bulges downward relative to the horizontal plane B as the nose profile expands from the leading edge point P1 to the midship 9 to a greater extent than the upper surface 51 of the nose 5 bulges upward relative to the horizontal plane B as the nose profile expands from the leading edge point P1 to the midship 9. This causes the nose profile of the nose 5 to be convex downwards.

Referring to fig. 1 to 2 and 6 to 7, the vtol aerial vehicle 1 further includes a pair of front wings 11 connected to the nose 5 and a pair of rear wings 13 connected to the tail 7. The pair of front wings 11 and the pair of rear wings 13 are arranged in a tandem wing (tandem wing) configuration. That is, the front wing 11 and the rear wing 13 are arranged in the front-rear direction, and the front wing 11 and the rear wing 13 are both a lifting surface and a mating surface. In this tandem wing arrangement, the aerodynamic focus of the VTOL aerial vehicle 1 is located between the front wing 11 and the rear wing 13. The arrangement position of the pair of front wings 11 on the head 5 is adjacent to the horizontal plane B in the vertical direction 15 perpendicular to the horizontal plane B. As used herein, the deployment location of a wing refers to the location of the root leading edge point of the wing.

The inventors have realized that the combination of the nose down profile and the tandem wing arrangement of the vtol aircraft 1 of the present application provides significant advantages. Specifically, the vertical take-off and landing aircraft 1 of the present application can meet the requirements of small size and high load by using the combination of the lower convex type nose profile and the tandem wing layout, and is particularly suitable for UAM scenes.

Firstly, since the front wing 11 and the rear wing 13 are both lifting surfaces and mutually matching planes, the vertical take-off and landing aircraft 1 can realize a large aerodynamic lift area with a small deployment length. On the one hand, this facilitates miniaturization of the VTOL aerial vehicle 1 to accommodate take-off, landing and storage requirements in UAM scenarios. On the other hand, this enables the vertical take-off and landing aircraft 1 to achieve high loads in a small size.

The conventional nose profile is generally convex (i.e., corresponding to the case where the lower surface 53 of the nose 5 projects downward relative to the horizontal plane B to a lesser extent as the nose profile expands from the leading edge point P1 to the midship 9 than the upper surface 51 of the nose 5 projects upward relative to the horizontal plane B as the nose profile expands from the leading edge point P1 to the midship 9) or symmetrical (i.e., corresponding to the case where the lower surface 53 of the nose 5 projects downward relative to the horizontal plane B to the same extent as the upper surface 51 of the nose 5 projects upward relative to the horizontal plane B as the nose profile expands from the leading edge point P1 to the midship 9).

In the case where the arrangement position of the front wing 11 on the nose 5 is adjacent to the horizontal plane B in the vertical direction 15, the lower convex nose profile of the nose 5 enables the nose 5 (leading edge point P1) to be disposed closer to the front wing 11 than the conventional upper convex profile and symmetrical profile. Thus, the lower nose profile of the nose 5 enables the front wing 11 to be arranged more forward relative to the rear wing 13, and thus a greater spacing between the front wing 11 and the rear wing 13, than a conventional upper nose profile and a symmetrical profile, for the same fuselage volume. On the one hand, this enables a considerable shortening of the length of the fuselage 3, which reduces the weight proportion of the fuselage structure and increases the load-carrying capacity of the vertical take-off and landing aircraft 1. On the other hand, the aerodynamic focus of the VTOL aerial vehicle 1 can be arranged further back. In the field of aircraft, in order to ensure static stability of flight in a flat flight state, it is necessary to position the center of gravity of the aircraft in front of the aerodynamic focus. With the VTOL aerial vehicle 1 of the present application, a larger center of gravity adjustment range can be provided to the VTOL aerial vehicle 1 because the aerodynamic focus can be arranged further back.

In addition, since the front wing 11 and the rear wing 13 are both a lifting surface and a matching plane, the lift-drag ratio of the vertical take-off and landing aircraft 1 can be increased to a greater extent, and the aerodynamic efficiency is higher. The front wing 11 and the rear wing 13 are mutually matched planes, so that a larger gravity center adjusting range can be provided for the vertical take-off and landing aircraft 1. The greater adjustment range of the center of gravity means greater flexibility in loading the VTOL aerial vehicle 1.

Therefore, compared with the vertical take-off and landing aircraft in the prior art, the vertical take-off and landing aircraft 1 can meet the requirements of small size and high load by combining the lower convex type aircraft nose profile and the tandem wing layout, and is particularly suitable for UAM (unmanned aerial vehicle) scenes.

Fig. 8 schematically shows the nose profile of the nose 5 of the VTOL aerial vehicle 1. Fig. 9 schematically shows a cross-sectional profile of the fuselage 3 of the vtol aircraft 1, taken from the plane of symmetry a, the boundary line of the nose 5 with the fuselage midsection 9 being schematically represented in fig. 9 by the imaginary line C. Fig. 10 schematically shows a cross-sectional profile of the nose 5 of the vtol aircraft 1, which may be, for example, the interface profile of the nose 5 with the midship 9, taken along the line I-I in fig. 6.

As shown in fig. 8, the horizontal plane B intersects the nose profile at a left dividing line S1 and a right dividing line S2. The left boundary line S1 intersects the mid-fuselage section 9 at a first left end point PL1, and the right boundary line S2 intersects the mid-fuselage section 9 at a first right end point PR1. Since the head contour of the head 5 is symmetrical about the symmetry plane a, the left boundary line S1 and the right boundary line S2 are also symmetrical about the symmetry plane a. The plane of symmetry a intersects the nose profile at an upper profile line S3 and a lower profile line S4. The upper contour line S3 intersects the fuselage middle section 9 at an upper end point PU, and the lower contour line S4 intersects the fuselage middle section 9 at a lower end point PD. In some embodiments, the upper contour line S3 and the lower contour line S4 bound the projected shape of the handpiece profile on the symmetry plane a. That is, the upper contour line S3 and the lower contour line S4 define the outermost contour of the head 5 in the vertical direction 15. In other partial embodiments, the upper contour line S3 and the lower contour line S4 may not be the outermost contour of the head 5 in the vertical direction 15.

As shown in fig. 9, the projection of the first left end point PL1 on the symmetry plane a is PL1', and the projection of the left boundary line S1 on the symmetry plane a is a line connecting P1 and PL 1'. Accordingly, the projection of the first right end point PR1 on the symmetry plane a coincides with PL1', and the projection of the right boundary line S2 on the symmetry plane a coincides with the line connecting P1 and PL 1'. The lower nose profile of the nose 5 may be such that: the centroid M of the cross-sectional shape of the nose contour taken by the symmetry plane a is located on the side of the projection of the left boundary line S1 on the symmetry plane a (i.e., the line connecting P1 and PL 1') near the lower end point PD and on the side of the perpendicular bisector D of the projection near the leading edge point P1. Such a lower cam profile is particularly beneficial in providing the aforementioned advantages.

With continued reference to fig. 9, the spacing between the upper and lower end points PU, PD in the vertical direction 15 defines a height of the head 5, the height of the head 5 being H. In some embodiments, the upper endpoint PU is aligned with the lower endpoint PD in the vertical direction 15. In other partial embodiments, the upper end points PU may not be aligned with the lower end points PD in the vertical direction 15, i.e. offset from each other. The interval between the leading edge point P1 and the upper end point PU in the vertical direction 15 is h1, and the interval between the leading edge point P1 and the lower end point PD in the vertical direction is h2. In some embodiments, H1 is in the range of 0 to 0.3H, and H2 is in the range of 0.7H to H. For example, when H1 is 0, H2 is H, the interval between the leading edge point P1 and the upper end point PU in the vertical direction 15 is 0, and the upper contour line S3 is a straight line. In this case, when the upper contour line S3 and the lower contour line S4 define the outermost contour of the head 5 in the vertical direction 15, the upper surface 51 is a flat surface extending from the leading edge point P1 to the midship 9. That is, the upper surface 51 bulges upward to zero relative to the horizontal plane B when the nose profile expands from the leading edge point P1 to the midship 9. Preferably, H1 is in the range of 0.1H to 0.2H, and H2 is in the range of 0.8H to 0.9H. More preferably, H1 is 0.15H and H2 is 0.85H. In some embodiments, H may be in the range of 1.2 meters to 2 meters. Preferably in the range of 1.2 to 1.6 meters.

In some embodiments, as best shown in FIG. 9, the upper contour line S3 is a warped curve with increasing height in a direction from the leading edge point P1 to the upper end point PU. The lower contour line S4 is a downward slope curve gradually decreasing in height in the direction from the leading edge point P1 to the lower end point PD. In one of these examples, the upper surface 51 and the lower surface 53 are each a continuous curved surface that flares from the leading edge point P1 of the nose 5 to the midship 9. Such a continuous curved surface is advantageous for improving aerodynamic performance.

As best shown in fig. 2 and 4, the position of the front wing 11 on the head 5 is closer to the upper end point PU than the lower end point PD in the vertical direction 15. In some embodiments, the spacing in the vertical direction 15 between the arrangement position of the front wing 11 on the head 5 and the upper end point PU is in the range of 0 to 0.3H. In some embodiments, the front wing 11 is attached to the nose 5 at a higher position than the rear wing 13 is on the tail 7. It should be understood that the present application is not so limited.

Further, as best shown in fig. 2, 4, 6, and 7, the arrangement position of the front wing 11 on the nose 5 is closer to the leading edge point P1 than the first left end point PL1 (or the first right end point PR 1) in the front-rear direction 19 parallel to the symmetry plane a and parallel to the horizontal plane B. The spacing between the leading point P1 and the first left end point PL1 in the fore-aft direction 19 defines the length of the head 5 (i.e., the length of the line connecting P1 and PL 1'), the length of the head 5 being L. L may be any suitable value. For example, L is in the range of H to 1.5H. As another example, L can be less than H or greater than 1.5H.

In some embodiments, the pitch in the front-rear direction 19 between the arrangement position of the front wing 11 on the head 5 and the leading edge point P1 is in the range of 0 to 0.3L. This is the benefit provided by the lower cam profile. It should be understood that the present application is not so limited.

As shown in fig. 7, the contour of the projection of the head 5 on the horizontal plane B (e.g., the bottom view contour of the head 5 shown in fig. 7) includes a left contour line S5 and a right contour line S6 extending from the leading edge point P1 to the midship 9, respectively. The left and right contour lines S5 and S6 are symmetrical about the plane of symmetry a and intersect the mid-fuselage section 9 at second left and right end points PL2 and PR2, respectively (fig. 10). The spacing between the second left end point PL2 and the second right end point PR2 in a transverse direction 21 perpendicular to the plane of symmetry a defines the width of the head 5, the width of the head 5 being W. W may be any suitable value. For example, W may be in the range of H to 1.5H. As another example, W can be less than H or greater than 1.5H.

The second left end point PL2 may not be higher than the first left end point PL1 in the vertical direction 15. The interval between the second left end point PL2 and the first left end point PL1 in the vertical direction 15 is H3, and H3 is in the range of 0 (the second left end point PL2 coincides with the first left end point PL 1) to 0.4H. In other partial embodiments, the second left end point PL2 may be higher than the first left end point PL1 in the vertical direction 15.

In some embodiments, as best shown in fig. 1 and 4, the lower surface 53 of the nose 5 of the VTOL aerial vehicle 1 may define at least one viewing window 40. The at least one viewing window 40 may occupy 60%, 70%, 80% or even 90% of the area of the lower surface 53. This can provide a good view of the driver (if any) and passengers when, for example, the vertical take-off and landing aircraft 1 is used for people.

Referring to fig. 1 to 7 and 9, the contour of the midship 9 and the tail 7 is also symmetrical about the plane of symmetry a. In some embodiments, the contours of the midship 9 and the tail 7 are tadpole shaped. In particular, the fuselage 3 is strongly contracted from the widest part of the fuselage midsection 9 up to the tail 7. The tadpole-shaped middle fuselage section 9 and the tail 7 can well support laminar boundary layers, and the infiltration area of the aircraft is reduced. It should be understood, however, that the profile of the midship 9 and the tail 7 of the present application is not so limited. For example, the profile of the midship 9 and the tail 7 may also be frusto-conical. In this case, the profile of the tail 7 approximates a truncated cone or a trapezoidal prism.

Referring to fig. 6 and 7, the pair of front wings 11 and the pair of rear wings 13 are in an X-shaped layout with the front wings forward-swept and the rear wings backward-swept. This X-type layout can further increase the spacing between the front wing 11 and the rear wing 13, and thus can provide a greater range of adjustment of the center of gravity for the VTOL aerial vehicle 1.

In some embodiments, the front wing area of the pair of front wings 11 is smaller than the rear wing area of the pair of rear wings 13. The smaller area of the front wing than the area of the rear wing is beneficial to moving the aerodynamic focus backwards. Preferably, the forward wing area is 50% to 80% of the aft wing area. More preferably, the forward wing area is 60% to 70% of the aft wing area. In some embodiments, the front wing has a front wing area of between 8 square meters and 10 square meters.

In some embodiments, the leading edge forward sweep of the forward wing 11 and the leading edge aft sweep of the aft wing 13 each do not exceed 25 °. As used in this application, the forward and aft sweep angles are the angles between the projection of the leading or trailing edge of the airfoil on the horizontal plane B and the transverse direction 21 perpendicular to the plane of symmetry a. Preferably, the forward sweep angle of the leading edge of the front wing 11 is 10 ° and the forward sweep angle of the trailing edge of the rear wing 13 is 15 °.

With continued reference to fig. 6 and 7, each front wing 11 includes a front wing tip 11a, a front wing root 11b, and a front wing body 11c extending between the front wing tip 11a and the front wing root 11b, and each rear wing 13 includes a rear wing tip 13a, a rear wing root 13b, and a rear wing body 13c extending between the rear wing tip 13a and the rear wing root 13 b.

In some embodiments, each front wing 11 of the pair of front wings 11 includes a front wing tip 11a. The leading edge of the front wing tip 11a is further forward than the leading edge point P1 in the forward-backward direction 19 parallel to the symmetry plane a and parallel to the horizontal plane B.

In some embodiments, a vertical tail 20 is disposed at the rear wing tip 13a of the rear wing 13. Vertical tail fin 20 includes a fixed vertical stabilizer (not shown) and a rudder (not shown) operable to manipulate the heading. In one of these embodiments, the vertical tail 20 comprises an upper section 20a extending beyond the rear wing 13 in the vertical direction 15, and a lower section 20b opposite the upper section 20a and extending beyond the rear wing 13 in the vertical direction 15. For example, a rudder may be provided on the upper section 20 a. As another example, a rudder may be provided on the lower section 20b. As another example, the rudder may be divided into two parts and disposed on the upper section 20a and the lower section 20b, respectively.

In some embodiments, the span of the pair of front wings 11 is shorter than the span of the pair of rear wings 13. The VTOL aerial vehicle 1 may further comprise a pair of elongated links 23 arranged symmetrically about the plane of symmetry A. Each elongated link 23 extends substantially parallel to the symmetry plane a, is connected to a respective one of the front wings 11 at the front wing tip 11a of the respective one of the pair of front wings 11, and is connected to a respective one of the rear wings 13 at the rear wing body 13c of the respective one of the pair of rear wings 13 corresponding to the respective one of the front wings 11. The vertical propulsion means comprise a plurality of rotors 25 arranged symmetrically on the connecting rod 23 with respect to the symmetry plane a. The plurality of rotors 25 are configured to provide horizontal power to the VTOL aerial vehicle 1. Thus, the VTOL aerial vehicle 1 is a composite wing VTOL aerial vehicle comprising tandem wings and rotors. The rotor 25 may be driven electrically, for example.

On one hand, the combined configuration of the front wing span shorter than the rear wing span and the connecting rod connecting mode can ensure that the wing span-wise appearance is continuous, and is favorable for aerodynamic performance. On the other hand, the combination configuration of the front wing span shorter than the rear wing span and the connecting rod connection mode is beneficial to shortening the force transmission distance of the connecting rod 23 through the wing and reducing the position and angle changes of the rotor 25 caused by the rigidity of the wing during vertical take-off and landing.

In some embodiments, plurality of rotors 25 includes at least six rotors 25. In one of these embodiments, as best shown in fig. 1-3 and 6, the plurality of rotors 25 includes eight rotors 25. In some embodiments, each link 23 comprises an intermediate section 23a between the front wing tip 11a and the rear wing body 13c, a forward section 23b extending from the intermediate section 23a beyond the front wing tip 11a, and a rearward section 23c extending from the intermediate section 23a beyond the rear wing body 13c. The intermediate section 23a, the front section 23b and the rear section 23c are each provided with a rotor 25. In one of these embodiments, as best shown in fig. 1-3 and 6, two rotors 25 are disposed on the intermediate section 23a of each link 23, and one rotor 25 is disposed on each of the forward section 23b and the aft section 23c. Such a rotor arrangement is particularly useful for compensating for variations in the center of gravity of the entire aircraft, and can provide a greater range of center of gravity adjustment for the VTOL aerial vehicle 1.

In some embodiments, the axis of rotation of each rotor 25 of plurality of rotors 25 is oriented perpendicular to horizontal plane B. In other embodiments, the axis of rotation of each rotor 25 of plurality of rotors 25 may not be oriented perpendicular to horizontal plane B _。 In some embodiments, a plurality of rotors 25 are arranged on a side of link 23 facing away from horizontal plane B.

As shown in fig. 1 and 2, the rotor 25 includes a blade 25a and a coupling mechanism 25b that rotatably couples the blade 25a to the link 23. At least the blades 25a of the rotor 25 are positioned higher than the fuselage 3 in the vertical direction 15. Preferably, the rotation range of the blades 25a of the rotor 25 does not overlap with the front wing 11, the rear wing 13, and the fuselage 3 in the vertical direction 15.

It should be appreciated that while the VTOL aerial vehicle 1 is described above as including rotors 25 connected to the front and rear wings 11, 13 by links 23, it should be understood that the VTOL aerial vehicle 1 may include other types of rotors as well, and the application is not limited thereto. For example, the VTOL aerial vehicle 1 may include a single rotor coupled to the midship 9 to provide horizontal power to the VTOL aerial vehicle 1. As another example, the vtol aerial vehicle 1 may include tandem dual rotors arranged on both sides of the fuselage 3 by suitable mechanisms to provide horizontal power to the vtol aerial vehicle 1.

The horizontal propulsion means of the vtol aerial vehicle 1 may comprise a pair of horizontal thrusters arranged symmetrically with respect to the plane of symmetry a and configured for providing horizontal power to the vtol aerial vehicle 1. For example, each horizontal thruster is configured and oriented to accelerate the air flow in the fore-aft direction 19. Each horizontal thruster is connected to a corresponding one of the rear wings 13 near the rear wing root 13b of the corresponding one of the pair of rear wings 13. This arrangement of the horizontal thrusters is advantageous in covering as much of the rear wing area as possible, thereby improving the high lift effect and thus the aerodynamic efficiency. For the tandem wing arrangement of the present application, it is more advantageous to provide more lift at the rear wing 13. Furthermore, the attachment of the horizontal thrusters to the rear wing 13 facilitates the balancing of the overall center of gravity of the VTOL aerial vehicle 1. In some embodiments, the horizontal thruster may be connected to a respective one of the rear wings 13 at a rear edge of the respective one of the rear wings 13. This can further assist in balancing the center of gravity of the entire aircraft of the VTOL aircraft 1. In other partial embodiments, the horizontal thruster may also be connected to a respective one of the rear wings 13 at the leading edge of the respective one of the rear wings 13. Since the wake velocity of the horizontal thruster is usually higher than the inflow velocity, this arrangement of the horizontal thruster can further increase the high lift effect and thus the aerodynamic efficiency.

The pair of horizontal thrusters may be a pair of ducted fans (e.g., ducted fans 27 shown in fig. 1-7) or a pair of propellers, and each horizontal thruster of the pair of horizontal thrusters defines an axis of rotation. In some embodiments, the axis of rotation of the horizontal thruster extends parallel to the symmetry plane a and parallel to the horizontal plane B. In some embodiments, the axis of rotation of the horizontal thruster is configured to be oriented along the fore-aft direction 19 and higher than the chord plane of the rear wing 13 in the vertical direction 15 perpendicular to the plane of symmetry a. This arrangement of the horizontal thruster accelerates the surface airflow over the rear wing, further increasing the high lift effect and thus the aerodynamic efficiency.

As shown in fig. 1 to 7, the VTOL aircraft 1 further comprises a pair of landing gears 30. Each landing gear 30 includes: a first leg 31 including a first end 31a connected to the body 3 and a second end 31b opposite the first end 31 a; a second leg 33 comprising a third end 33a connected to the fuselage 3, and a fourth end 33b opposite the third end 33 a; and a middle section 35 connected between the second end 31b and the fourth end 33 b. The middle section 35 includes a first section 35a connecting the second end 31b, a second section 35b connecting the fourth end 33b, and a bend section 35c connecting the first section 35a and the second section 35b. The bending section 35c is configured to bend toward the fuselage 3 such that when the vtol aircraft 1 is parked on a flat base surface, the first section 35a and the second section 35b contact the base surface, while the bending section 35c does not contact the base surface. As used in this application, a base surface refers to a surface, such as an apron, a road surface, or the like, on which the vtol aircraft 1 can be parked.

The inventors have realised that the landing gear 30 of the vtol aircraft 1 of the present application can provide significant advantages. On the one hand, since only the first and second sections 35a, 35b of the center section 35 contact the base surface when the VTOL aircraft 1 is parked on a flat base surface, stress is concentrated on the first and second sections 35a, 35b. When the first section 35a and the second section 35b are impacted by the base surface, the bent section 35c can allow the first section 35a and the second section 35b to be slightly deformed to absorb the impact. On the other hand, since the bent section 35c is bent toward the fuselage 3, the bent section 35c can form a boarding step, which can reduce manufacturing materials and reduce the weight of the aircraft. For example, the bending section 35c may have a tread surface formed thereon.

In some embodiments, as best shown in fig. 7, the first and second sections 35a, 35b are elongated and the first and second sections 35a, 35b are collinear. For example, the first section 35a and the second section 35B are each oriented along a front-to-rear direction 19 parallel to the symmetry plane a and parallel to the horizontal plane B.

In some embodiments, as best shown in fig. 11, the cross-section of the first leg 31 taken in a plane parallel to the horizontal plane B is drop-shaped in profile to reduce drag. Similarly, the second leg 33 has a cross-section taken in a plane parallel to the horizontal plane B, the contour of which is drop-shaped.

In some embodiments, the first leg 31 is elongated and makes an angle of 45 ° to 135 ° with the first section 35 a. In some embodiments, the second leg 33 is elongated and makes an angle of 45 ° to 135 ° with the second section 35b.

In some embodiments, as best shown in fig. 4 and 5, the first leg 31, the second leg 33, the first section 35a, and the second section 35b are coplanar with a first plane (not shown). The first plane is inclined with respect to the symmetry plane a. Preferably, the first plane is at an angle of between 0 ° and 50 °, preferably 40 °, to the plane of symmetry a. In one of these embodiments, as shown in fig. 4 and 5, the bend section 35c is offset relative to the first plane in a direction away from the plane of symmetry a. For example, the bending section 35c may be parallel to the symmetry plane a. This configuration of the bending section 35c enables an increase in the spacing between the bending section 35c and the fuselage 3 in the transverse direction 21, compared to a situation in which the bending section 35c is not offset relative to the first plane, thus enabling a suitable boarding step to be provided with a shorter landing gear extension. This enables a further reduction in manufacturing materials and thus a reduction in aircraft weight.

In some embodiments, bend segment 35c includes a first portion 351 connecting first segment 35a, a second portion 352 connecting second segment 35b, and a third portion 353 connecting first portion 351 and second portion 352. The third portion 353 is parallel to the first and second sections 35a, 35b.

The landing gear 30 may be sized to support the vtol aircraft 1 to elevate the front wing 11, the rear wing 13, and the link 23 away from the top of the head of the boarding person. For example, the landing gear 30 may be sized to raise the front wing 11, the rear wing 13, and the link 23 no less than 1.8 meters.

It should be appreciated that the landing gear 30 could be used with other types of aircraft to provide the aforementioned advantages. That is, the present application also proposes a landing gear for an aircraft, comprising a pair of landing gears 30 as previously described. The aircraft may be, for example, any suitable unmanned or manned aircraft, and have any suitable wing and power configuration. Similar to that described above in connection with the VTOL aircraft 1, the pair of landing gears 30 are configured to be symmetrically arranged about a plane of symmetry of the aircraft's fuselage (e.g., the aforementioned plane of symmetry A). Each landing gear 30 includes: a first leg 31 comprising a first end 31a connected to the fuselage of the aircraft, and a second end 31b opposite the first end 31 a; a second leg 33 comprising a third end 33a connected to the fuselage of the aircraft, and a fourth end 33b opposite the third end 33 a; and a middle section 35 connected between the second end 31b and the fourth end 33 b. The middle section 35 includes a first section 35a connecting the second end 31b, a second section 35b connecting the fourth end 33b, and a bend section 35c connecting the first section 35a and the second section 35b. The bend section 35c is configured to bend towards the fuselage of the aircraft such that when the aircraft is parked on a flat base surface, the first and second sections 35a, 35b contact the base surface, while the bend section 35c does not contact the base surface. As used in this application, the plane of symmetry of the aircraft refers to an imaginary plane that divides the aircraft into two halves that are substantially mirror images of each other. It should be understood that this does not mean that the aircraft is limited to being completely symmetrical about the plane of symmetry.

In some embodiments, the first and second sections 35a, 35b are elongated, and the first and second sections 35a, 35b are collinear. In some embodiments, first section 35a and second section 35B are each oriented along a direction (e.g., the aforementioned anterior-posterior direction 19) that is parallel to the plane of symmetry and parallel to a plane (e.g., the aforementioned horizontal plane B) that is perpendicular to the plane of symmetry. In some embodiments, the cross-section of the first leg 31 taken in a plane perpendicular to the plane of symmetry is drop-shaped in profile to reduce drag. In some embodiments, the cross-section of the second leg 33 taken in a plane perpendicular to the plane of symmetry is drop-shaped in profile to reduce drag.

In some embodiments, the first leg 31 is elongated and makes an angle of 45 ° to 135 ° with the first section 35 a. In some embodiments, the second leg 33 is elongated and makes an angle of 45 ° to 135 ° with the second section 35b. In some embodiments, the first leg 31, the second leg 33, the first section 35a, and the second section 35b are coplanar with a first plane (not shown). The first plane is inclined with respect to the plane of symmetry. Preferably, the first plane is at an angle of between 0 ° and 50 °, preferably 40 °, to the plane of symmetry. In one of these embodiments, the bend section 35c is offset relative to the first plane in a direction away from the plane of symmetry. For example, the bending section 35c may be parallel to the symmetry plane. In some embodiments, bend segment 35c includes a first portion 351 connecting first segment 35a, a second portion 352 connecting second segment 35b, and a third portion 353 connecting first portion 351 and second portion 352. The third portion 353 is parallel to the first section 35a and the second section 35b.

It will be understood that the terms "first," "second," "third," and "fourth" are used merely to distinguish one element or portion from another element or portion, but these elements and/or portions should not be limited by such terms.

The present application is described in detail above with reference to specific embodiments. It is to be understood that both the foregoing description and the embodiments shown in the drawings are to be considered exemplary and not restrictive of the application. It will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit of the application, and these changes and modifications do not depart from the scope of the application.

Claims (10)

1. Landing gear for an aircraft comprising a fuselage, characterized in that it comprises a pair of landing gears (30) configured for being arranged symmetrically with respect to a plane of symmetry of the fuselage, each landing gear (30) of said pair of landing gears (30) comprising:

a first leg (31), said first leg (31) comprising a first end (31 a) connected to said fuselage (3), and a second end (31 b) opposite to said first end (31 a);

a second leg (33), said second leg (33) comprising a third end (33 a) connected to said fuselage (3), and a fourth end (33 b) opposite to said third end (33 a); and

a middle section (35) connected between the second end (31 b) and the fourth end (33 b), the middle section (35) comprising a first section (35 a) connecting the second end (31 b), a second section (35 b) connecting the fourth end (33 b), and a bending section (35 c) connecting the first section (35 a) and the second section (35 b), the bending section (35 c) being configured to bend towards the fuselage (3) such that when the aircraft rests on a flat base surface, the first section (35 a) and the second section (35 b) contact the base surface, while the bending section (35 c) does not contact the base surface.

2. A landing gear according to claim 1, characterised in that the first and second sections (35 a, 35 b) are elongate and the first and second sections (35 a, 35 b) are co-linear.

3. A landing gear according to claim 1 or 2, wherein the first and second sections (35 a, 35 b) are each oriented along a direction parallel to the plane of symmetry and to a plane perpendicular thereto.

4. A landing gear according to claim 1 or 2, wherein:

the profile of the cross section of the first leg (31) taken by a plane perpendicular to the plane of symmetry is drop-shaped, so as to reduce the resistance; and/or

The profile of the cross section of the second leg (33) taken by a plane perpendicular to the plane of symmetry is drop-shaped, so as to reduce the resistance.

5. A landing gear according to claim 1 or 2, wherein:

said first leg (31) being elongate and angled at 45 ° to 135 ° to said first section (35 a); and/or

The second leg (33) is elongate and forms an angle of 45 ° to 135 ° with the second section (35 b).

6. A landing gear according to claim 1 or 2, wherein:

-said first leg (31), said second leg (33), said first section (35 a) and said second section (35 b) are coplanar to a first plane inclined with respect to said plane of symmetry; and

the bending section (35 c) is offset relative to the first plane in a direction away from the plane of symmetry.

7. A landing gear according to claim 6, characterised in that the bent section (35 c) is parallel to the plane of symmetry.

8. A landing gear according to claim 6, wherein the first plane is angled at between 0 ° and 50 ° to the plane of symmetry.

9. A landing gear according to claim 8, wherein the included angle is 40 °.

10. The landing gear of claim 2, wherein:

the bending section (35 c) comprises a first portion (351) connecting the first section (35 a), a second portion (352) connecting the second section (35 b), and a third portion (353) connecting the first portion (351) and the second portion (352), the third portion (353) being parallel to the first section (35 a) and the second section (35 b).

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