CN218907594U

CN218907594U - Folding built-in boarding ladder with pedals

Info

Publication number: CN218907594U
Application number: CN202223498420.6U
Authority: CN
Inventors: 林振华; 余志明; 罗昊宇; 袁平湘; 黄颖; 刘贵芳; 许小妹; 张勇
Original assignee: Jiangxi Hongdu Aviation Industry Group Co Ltd
Current assignee: Jiangxi Hongdu Aviation Industry Group Co Ltd
Priority date: 2022-12-26
Filing date: 2022-12-26
Publication date: 2023-04-25
Anticipated expiration: 2032-12-26

Abstract

The utility model discloses a folding built-in boarding ladder with pedals, which comprises an outer cylinder, a first inner cylinder, a second inner cylinder, a first pedal, a second pedal, a third pedal, a first stay bar and a second stay bar, wherein the first stay bar is arranged on the outer cylinder; the upper end of the outer cylinder is hinged with the airplane, the left side of the lower end of the outer cylinder is hinged with a first pedal, the second inner cylinder can slide relative to the first inner cylinder, the first inner cylinder can slide relative to the outer cylinder, the second pedal is hinged with the right side of the lower end of the first inner cylinder, the third pedal is hinged with the left side of the lower end of the second inner cylinder, one end of a first stay bar is hinged with one end of a second stay bar, the other end of the first stay bar is hinged with the front side of the lower end of the first inner cylinder, and the other end of the second stay bar is hinged with the front side of the lower end of the outer cylinder; the utility model has the advantages that: the folding and unfolding are convenient, the occupied space after folding is small, the folding device is suitable for military aircraft, quick landing and off can be realized, and the work of ground staff is reduced.

Description

Folding built-in boarding ladder with pedals

Technical Field

The utility model belongs to the field of aircraft structural design, and particularly relates to a pedal-foldable built-in boarding ladder.

Background

The external boarding ladder is an independent component, belongs to ground random equipment, needs ground staff to carry, and increases the work of the ground staff. The random built-in boarding is connected with the airplane structure, the military aircraft adopts random boarding to provide a convenient boarding and disembarking channel for air and ground staff, at present, the pedals of the telescopic rod type random built-in boarding ladder at home and abroad are generally not foldable, or the folding is adopted, the occupied space is large after the folding of the non-foldable pedal boarding ladder, and the convenience of the boarding ladder is reduced by manually folding the pedals.

Disclosure of Invention

Aiming at the prior art, the utility model aims to overcome the defects in the prior art and adapt to the actual needs, thereby providing the pedal-foldable built-in boarding ladder based on the telescopic rod type random built-in boarding ladder.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the pedal is foldable and internally provided with an boarding ladder, and comprises an outer cylinder, a first inner cylinder, a second inner cylinder, a first pedal, a second pedal, a third pedal, a first stay bar and a second stay bar; the upper end of the outer cylinder is hinged with the airplane, the left side of the lower end of the outer cylinder is hinged with a first pedal, the outer cylinder is sleeved on the upper end of the first inner cylinder, the first inner cylinder is sleeved on the upper end of the second inner cylinder, the second inner cylinder can slide relative to the first inner cylinder, the first inner cylinder can slide relative to the outer cylinder, the second pedal is hinged with the right side of the lower end of the first inner cylinder, the third pedal is hinged with the left side of the lower end of the second inner cylinder, one end of a first supporting rod is hinged with one end of a second supporting rod, the other end of the first supporting rod is hinged with the front side of the lower end of the first inner cylinder, the other end of the second supporting rod is hinged with the front side of the lower end of the outer cylinder, the second inner cylinder can drive the third pedal to rotate upwards to be abutted to the lower side of the left side of the outer cylinder when the second inner cylinder is retracted and slid in an upward direction, the third pedal can contact with the first pedal to push the first pedal to rotate upward to be abutted to the upper side of the left side of the outer cylinder when the third pedal continues to move upward, the first inner cylinder can drive the first supporting rod and the second pedal to rotate upward when the first inner cylinder is retracted upward to rotate together, and the first supporting rod can rotate upward to be abutted to the front side of the first supporting rod when the first supporting rod is pushed upward and folded upward to act together to complete a boarding ladder; when the boarding ladder is unfolded, the second inner cylinder is extended out in a sliding way from the first inner cylinder, the first inner cylinder is driven to extend out in a sliding way from the outer cylinder, the first supporting rod and the second supporting rod are unfolded in a follow-up way, and the first pedal, the second pedal and the third pedal are unfolded under the action of gravity.

Further, the overall appearance of first footboard, second footboard and third footboard is right angle triangle form.

Further, the outer cylinder is provided with a first lug, a second lug, a third lug and a first ejector rod, the first lug is arranged at the top of the outer cylinder, the second lug and the third lug are respectively arranged at the left side of the lower end and the front side of the lower end of the outer cylinder, the first ejector rod is arranged at the right side of the bottom of the outer cylinder, the first inner cylinder is provided with a fourth lug, a fifth lug and a second ejector rod, the fourth lug is arranged at the right side of the lower end of the first inner cylinder, the fifth lug is provided with two, the two fifth lugs are oppositely arranged at the front side of the lower end of the first inner cylinder, the second ejector rod is arranged at the left side of the bottom of the first inner cylinder, the left side of the lower end of the second inner cylinder is provided with a sixth lug, the first pedal mounting hole and the flange strip are arranged at the right angle of the first pedal, the flange strip is arranged at the long right angle edge of the first pedal, the two ends of the flange strip extend outwards, be equipped with second footboard mounting hole and first folding connecting rod on the second footboard, the right angle department of second footboard is located to second footboard mounting hole, first folding connecting rod one end is fixed in the long right angle edge of second footboard, the other end is located the second footboard outside, be equipped with third footboard mounting hole on the third footboard, second folding connecting rod, direction rim strip and recess, right angle department of third footboard is located to third footboard mounting hole, second folding connecting rod one end is fixed in on the long right angle limit lower extreme of third footboard, the other end is located the third footboard outside, direction rim strip and recess are all located the long right angle edge upper end of third footboard, first vaulting pole both ends are equipped with first vaulting pole mounting hole and second vaulting pole mounting hole respectively, second vaulting pole both ends are equipped with third vaulting pole mounting hole and fourth vaulting pole mounting hole respectively.

Further, the top of the outer cylinder is hinged with the aircraft through a first lug, the left side of the lower end of the outer cylinder is hinged with a first pedal mounting hole on a first pedal through a second lug, the long right-angle side of the first pedal is upwards arranged, the front side of the lower end of the outer cylinder is hinged with a fourth supporting rod mounting hole on the other end of a second supporting rod through a third lug, the right side of the lower end of the first inner cylinder is hinged with a second pedal mounting hole on the second pedal through a fourth lug, the long right-angle side of the second pedal is upwards arranged and the other end of a first folding connecting rod is arranged towards a first ejector rod, the front side of the lower end of the first inner cylinder is hinged with a second supporting rod mounting hole on the other end of the first pedal through two fifth lugs, the second inner cylinder is hinged with a third pedal mounting hole on the other end of the first pedal through a sixth lug, the other end of the third pedal is upwards arranged towards the second ejector rod, one end of the first supporting rod is hinged with a third supporting rod mounting hole on the first inner cylinder through the first supporting rod mounting hole, the second supporting rod mounting hole and the second supporting rod is upwards arranged, the second supporting rod is upwards rotated along with the second pedal, the second pedal is rotated, the second pedal can rotate upwards, and can rotate upwards along with the second pedal mounting hole, and can rotate upwards along with the second pedal, and rotate upwards, and rotate along with the second pedal, and rotate up to the second pedal, and rotate along with the second pedal, and rotate the second pedal, when the guiding edge strip on the third pedal contacts with the flange strip on the first pedal, the guiding edge strip can jack up the flange strip on the first pedal, so that the first pedal is driven to rotate around the first pedal mounting hole.

Further, the width of the notch of the groove is larger than the width of the first pedal and smaller than the outline width of the flange strip.

Further, the first supporting rod and the second supporting rod are semicircular at two ends and are rectangular in middle.

Further, the hole spacing of the first stay bar mounting holes and the second stay bar mounting holes on the two ends of the first stay bar is larger than the hole spacing of the third stay bar mounting holes and the fourth stay bar mounting holes on the two ends of the second stay bar, and the distance difference of the hole spacing of the first stay bar mounting holes and the second stay bar mounting holes is coordinated with the distance between the third lug and the fifth lug when the boarding ladder is in a bundling state.

Further, when the first pedal, the second pedal and the third pedal are installed, the first pedal, the second pedal and the third pedal are located on two sides of the outer cylinder, the first pedal and the third pedal are located on the left side of the outer cylinder, the first pedal is located at the upper end of the third pedal, and the second pedal is located on the right side of the outer cylinder.

The utility model has the beneficial effects that: the folding and unfolding are convenient, the occupied space after folding is small, the folding device is suitable for military aircraft, quick landing and off can be realized, and the work of ground staff is reduced.

Drawings

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is an exploded view of the present utility model;

FIG. 3 is a schematic view of the initial folding principle of the present utility model;

FIG. 4 is a schematic diagram of the third pedal of the present utility model pushing the first pedal to fold;

fig. 5 is an expanded schematic view of the present utility model.

Wherein: 1. the outer barrel, 2, first inner barrel, 3, second inner barrel, 4, first pedal, 5, second pedal, 6, third pedal, 7, first stay, 8, second stay, 11, first tab, 12, second tab, 13, third tab, 14, first lifter, 21, fourth tab, 22, fifth tab, 23, second lifter, 31, sixth tab, 41, first pedal mounting hole, 42, flange strip, 51, second pedal mounting hole, 52, first fold link, 61, third pedal mounting hole, 62, second fold link, 63, guide flange strip, 64, groove, 71, first stay mounting hole, 72, second stay mounting hole, 78, support point, 81, third stay mounting hole, 82, fourth stay mounting hole.

Detailed Description

The following describes specific embodiments of the present utility model in detail with reference to the drawings. It should be understood that the detailed description and specific examples, while indicating and illustrating the utility model, are not intended to limit the utility model.

In the description of the present application, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," and the like indicate an orientation or a positional relationship based on that shown in the drawings, merely for convenience of description and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first," second, "" third, "" fourth, "" fifth, "and sixth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "connected," "provided," "engaged/connected," "clamped," etc. are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art in a specific context.

Examples

As shown in fig. 1 to 5, the present utility model provides a step-foldable built-in boarding ladder, comprising an outer barrel 1, a first inner barrel 2, a second inner barrel 3, a first step 4, a second step 5, a third step 6, a first stay 7 and a second stay 8; the upper end of the outer cylinder 1 is hinged with an airplane, the left side of the lower end is hinged with a first pedal 4, the outer cylinder 1 is sleeved on the upper end of a first inner cylinder 2, the first inner cylinder 2 is sleeved on the upper end of a second inner cylinder 3, the second inner cylinder 3 can slide relative to the first inner cylinder 2, the first inner cylinder 2 can slide relative to the outer cylinder 1, the second pedal 5 is hinged with the right side of the lower end of the first inner cylinder, the third pedal 6 is hinged with the left side of the lower end of the second inner cylinder 3, one end of a first supporting rod 7 is hinged with one end of a second supporting rod 8, the other end of the first supporting rod 7 is hinged with the front side of the lower end of the first inner cylinder 2, the other end of the second supporting rod 8 is hinged with the front side of the lower end of the outer cylinder 1, when the second inner cylinder 3 slides in the first inner cylinder 2 in a beam-retracting manner, the third pedal 6 can be driven to rotate upwards so as to be abutted against the lower left side of the outer cylinder 1, when the third pedal 6 continues to move upwards, the third pedal can be contacted with the first pedal 4 and push the first pedal 4 to rotate upwards so as to be abutted against the upper left side of the outer cylinder 1, when the first inner cylinder 2 slides in the outer cylinder 1 in a beam-retracting manner, the first supporting rod 7 and the second pedal 5 can be driven to rotate upwards so as to enable the second pedal 5 to be abutted against the right side of the outer cylinder, and when the first supporting rod 7 rotates upwards, the second supporting rod 8 can be pushed to rotate upwards so as to be abutted against the front side of the outer cylinder 1 together, so that the folding action of the boarding ladder is completed; when the boarding ladder is unfolded, the second inner cylinder 3 is extended out in a sliding way from the first inner cylinder 2, the first inner cylinder 2 is driven to extend out in a sliding way from the outer cylinder 1, the first supporting rod 7 and the second supporting rod 8 are unfolded in a follow-up way, and the first pedal 4, the second pedal 5 and the third pedal 6 are unfolded under the action of gravity.

Preferably, the first pedal 4, the second pedal 5 and the third pedal 6 are all in the shape of right triangle.

Preferably, the outer cylinder 1 is provided with a first lug 11, a second lug 12, a third lug 13 and a first ejector rod 14, the first lug 11 is arranged at the top of the outer cylinder 1, the second lug 12 and the third lug 13 are respectively arranged at the left side and the front side of the lower end of the outer cylinder 1, the first ejector rod 14 is arranged at the right side of the bottom of the outer cylinder 1, the first inner cylinder 2 is provided with a fourth lug 21, a fifth lug 22 and a second ejector rod 23, the fourth lug 21 is arranged at the right side of the lower end of the first inner cylinder 2, the fifth lug 22 is provided with two, the two fifth lugs 22 are oppositely arranged at the front side of the lower end of the first inner cylinder 2, the second ejector rod 23 is arranged at the left side of the bottom of the first inner cylinder 2, the left side of the lower end of the second inner cylinder 3 is provided with a sixth lug 31, the first pedal 4 is provided with a first pedal mounting hole 41 and a flange 42, the first pedal mounting hole 41 is arranged at the right angle of the first pedal 4, the flange 42 is arranged at the right angle of the first pedal 4, the two ends extend outwards, the second pedal 5 is provided with a second pedal mounting hole 51 and a first folding connecting rod 52, the second pedal mounting hole 51 is arranged at the right angle of the second pedal 5, one end of the first folding connecting rod 52 is fixed at the long right angle edge of the second pedal 5, namely, one end of the first folding connecting rod 52 is fixed at the position close to the end of the second pedal mounting hole 51, the other end is positioned at the outer side of the second pedal 5, the third pedal 6 is provided with a third pedal mounting hole 61, a second folding connecting rod 62, a guiding edge strip 63 and a groove 64, the third pedal mounting hole 61 is arranged at the right angle of the third pedal 6, one end of the second folding connecting rod 62 is fixed at the lower end of the long right angle edge of the third pedal 6, namely, one end of the second folding connecting rod 62 is fixed at the position close to the end of the third pedal mounting hole 61, the other end is positioned at the outer side of the third pedal 6, the guiding edge strip 63 and the groove 64 are both arranged at the upper end of the long right angle edge of the third pedal 6, namely, the guide edge strip 63 and the groove 64 are respectively arranged at the end far away from the third pedal mounting hole 61, the first supporting rod 7 is respectively provided with a first supporting rod mounting hole 71 and a second supporting rod mounting hole 72, and the second supporting rod 8 is respectively provided with a third supporting rod mounting hole 81 and a fourth supporting rod mounting hole 82.

Preferably, the top of the outer cylinder 1 is hinged with the airplane through a first lug 11, the left side of the lower end of the outer cylinder 1 is hinged with a first pedal mounting hole 41 on a first pedal 4 through a second lug 12, the long right-angle side of the first pedal 4 is upwards arranged, the front side of the lower end of the outer cylinder 1 is hinged with a fourth supporting rod mounting hole 82 on the other end of a second supporting rod 8 through a third lug 13, the right side of the lower end of the first inner cylinder 2 is hinged with a second pedal mounting hole 51 on a second pedal 5 through a fourth lug 21, the long right-angle side of the second pedal 5 is upwards arranged, the other end of a first folding connecting rod 52 is arranged towards a first ejector rod 14, the front side of the lower end of the first inner cylinder 2 is hinged with a second supporting rod mounting hole 72 on the other end of the first supporting rod 7 through two fifth lugs 22, the second inner cylinder 3 is hinged with a third pedal mounting hole 61 on a third pedal 6 through a sixth lug 31, and the long right-angle side of the third pedal 6 is upward, the other end of the second folding connecting rod 62 is toward the second ejector rod 23, one end of the first supporting rod 7 is hinged with a third supporting rod mounting hole 81 on one end of the second supporting rod 8 through a first supporting rod mounting hole 71, the hinged ends of the first supporting rod 7 and the second supporting rod 8 are supporting points 78, and are supported on the outer surface of the airplane through the supporting points 78, when the second ejector rod 23 contacts with the other end of the second folding connecting rod 62, the second ejector rod 23 can drive the second folding connecting rod 62 to rotate around the third pedal mounting hole 61, thereby driving the third pedal 6 to rotate upward, when the first inner barrel 2 performs the retraction sliding, the first supporting rod 7 can fold upward along with the movement of the first inner barrel 2, and pushes the second supporting rod 8 to fold upward, when the first ejector rod 14 contacts with the other end of the first folding connecting rod 52, the first ejector rod 14 can drive the first folding connecting rod 52 to rotate around the second pedal mounting hole 51, thereby drive the second footboard 5 to rotate upwards, when the third footboard 6 is fully folded and continues to move upwards, the recess 64 on the third footboard 6 can block into the front and back both ends of first footboard 4, and when the guiding edge strip 63 on the third footboard 6 contacts with the edge strip 42 on the first footboard 4, the guiding edge strip 63 can jack up the edge strip 42 on the first footboard 4 to drive the first footboard 4 to rotate around the first footboard mounting hole 41.

Preferably, the groove 64 has a notch width that is greater than the width of the first step 4 and less than the contour width of the flange strip 42.

Preferably, the first supporting rod 7 and the second supporting rod 8 are semicircular at two ends and have a rectangular structure in the middle.

Preferably, the hole spacing between the first strut mounting holes 71 and the second strut mounting holes 72 on the two ends of the first strut 7 is larger than the hole spacing between the third strut mounting holes 81 and the fourth strut mounting holes 82 on the two ends of the second strut 8, and the difference between the hole spacing is matched with the distance between the third lug 13 and the fifth lug 22 in the folding built-in boarding ladder closing state of the pedal.

Preferably, the first pedal 4, the second pedal 5 and the third pedal 6 are all arranged on two sides of the outer cylinder 1 when being arranged, the first pedal 4 and the third pedal 6 are arranged on the left side of the outer cylinder 1, the first pedal 4 is arranged at the upper end of the third pedal 6, and the second pedal 5 is arranged on the right side of the outer cylinder 1.

The working principle of the utility model is as follows: in the folding process of the boarding ladder, as shown in fig. 3, the second inner cylinder 3 of the boarding ladder is folded and slid in the first inner cylinder 2, when the boarding ladder slides to a certain position, the second ejector rod 23 contacts with the second folding connecting rod 62 and slides continuously, the second ejector rod 23 drives the second folding connecting rod 62 to rotate around the third pedal mounting hole 61, when the second inner cylinder 3 is completely folded, the third pedal 6 completes folding, the first inner cylinder 2 slides in the outer cylinder 1 in a folding way, the first supporting rod 7 pushes the second supporting rod 8 to fold upwards, when the boarding ladder slides to a certain position, the first ejector rod 14 contacts with the first folding connecting rod 52 and slides continuously, the first ejector rod 14 drives the first folding connecting rod 52 to rotate around the second pedal mounting hole 51, when the first inner cylinder 2 is completely folded, the first supporting rod 7, the second supporting rod 8 and the second pedal 5 complete folding, as shown in fig. 4, the guide edge strip 63 on the third pedal 6 contacts with the flange strip 42 on the first pedal 4, when the groove 64 on the third pedal 6 is blocked into the first pedal 4, and the first pedal 4 can rotate continuously, and the flange strip 4 is folded, thus completing folding of the first pedal 4.

In the unfolding process of the boarding ladder, the second inner cylinder 3 is extended out in a sliding way from the first inner cylinder 2, the first inner cylinder 2 is driven to extend out in a sliding way from the outer cylinder 1, the first supporting rod 7 and the second supporting rod 8 are unfolded in a follow-up way, and the first pedal 4, the second pedal 5 and the third pedal 6 are unfolded under the action of gravity.

The use of the boarding ladder of the utility model: the airstairs, after deployment, support the support points 78 to the exterior surface of the aircraft, as shown in fig. 5.

Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present utility model, and not for limiting the same; although the utility model has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the utility model.

Furthermore, those skilled in the art will appreciate that while some embodiments herein include some features but not others included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the utility model and form different embodiments. For example, in the claims below, any of the claimed embodiments may be used in any combination. The information disclosed in this background section is only for enhancement of understanding of the general background of the utility model and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

Claims

1. The folding built-in airstairs of footboard, its characterized in that: the device comprises an outer cylinder, a first inner cylinder, a second inner cylinder, a first pedal, a second pedal, a third pedal, a first stay bar and a second stay bar; the upper end of the outer cylinder is hinged with the airplane, the left side of the lower end of the outer cylinder is hinged with a first pedal, the outer cylinder is sleeved on the upper end of the first inner cylinder, the first inner cylinder is sleeved on the upper end of the second inner cylinder, the second inner cylinder can slide relative to the first inner cylinder, the first inner cylinder can slide relative to the outer cylinder, the second pedal is hinged with the right side of the lower end of the first inner cylinder, the third pedal is hinged with the left side of the lower end of the second inner cylinder, one end of a first supporting rod is hinged with one end of a second supporting rod, the other end of the first supporting rod is hinged with the front side of the lower end of the first inner cylinder, the other end of the second supporting rod is hinged with the front side of the lower end of the outer cylinder, the second inner cylinder can drive the third pedal to rotate upwards to be abutted to the lower side of the left side of the outer cylinder when the second inner cylinder is retracted and slid in an upward direction, the third pedal can contact with the first pedal to push the first pedal to rotate upward to be abutted to the upper side of the left side of the outer cylinder when the third pedal continues to move upward, the first inner cylinder can drive the first supporting rod and the second pedal to rotate upward when the first inner cylinder is retracted upward to rotate together, and the first supporting rod can rotate upward to be abutted to the front side of the first supporting rod when the first supporting rod is pushed upward and folded upward to act together to complete a boarding ladder; when the boarding ladder is unfolded, the second inner cylinder is extended out in a sliding way from the first inner cylinder, the first inner cylinder is driven to extend out in a sliding way from the outer cylinder, the first supporting rod and the second supporting rod are unfolded in a follow-up way, and the first pedal, the second pedal and the third pedal are unfolded under the action of gravity.

2. The step-foldable built-in boarding ladder of claim 1, wherein: the overall appearance of the first pedal, the second pedal and the third pedal is right-angle triangle body shape.

3. The step-foldable built-in boarding ladder of claim 2, wherein: the outer cylinder is provided with a first lug, a second lug, a third lug and a first ejector rod, the first lug is arranged at the top of the outer cylinder, the second lug and the third lug are respectively arranged at the left side of the lower end and the front side of the lower end of the outer cylinder, the first ejector rod is arranged at the right side of the bottom of the outer cylinder, the first inner cylinder is provided with a fourth lug, a fifth lug and a second ejector rod, the fourth lug is arranged at the right side of the lower end of the first inner cylinder, the fifth lug is provided with two, the two fifth lugs are oppositely arranged at the front side of the lower end of the first inner cylinder, the second ejector rod is arranged at the left side of the bottom of the first inner cylinder, the left side of the lower end of the second inner cylinder is provided with a sixth lug, the first pedal mounting hole and the flange strip are arranged at the right angle of the first pedal, the flange strip is arranged at the long right angle edge of the first pedal, and the two ends of the flange strip extend outwards, be equipped with second footboard mounting hole and first folding connecting rod on the second footboard, the right angle department of second footboard is located to second footboard mounting hole, first folding connecting rod one end is fixed in the long right angle edge of second footboard, the other end is located the second footboard outside, be equipped with third footboard mounting hole on the third footboard, second folding connecting rod, direction rim strip and recess, right angle department of third footboard is located to third footboard mounting hole, second folding connecting rod one end is fixed in on the long right angle limit lower extreme of third footboard, the other end is located the third footboard outside, direction rim strip and recess are all located the long right angle edge upper end of third footboard, first vaulting pole both ends are equipped with first vaulting pole mounting hole and second vaulting pole mounting hole respectively, second vaulting pole both ends are equipped with third vaulting pole mounting hole and fourth vaulting pole mounting hole respectively.

4. A step-foldable built-in boarding ladder according to claim 3, characterized in that: the top of the outer cylinder is hinged with the aircraft through a first lug, the left side of the lower end of the outer cylinder is hinged with a first pedal mounting hole on a first pedal through a second lug, the front side of the lower end of the outer cylinder is hinged with a fourth pedal mounting hole on the other end of a second supporting rod through a third lug, the right side of the lower end of the first inner cylinder is hinged with a second pedal mounting hole on the second pedal through a fourth lug, the other end of a first folding connecting rod is arranged towards a first ejector rod, the front side of the lower end of the first inner cylinder is hinged with a second supporting rod mounting hole on the other end of the first supporting rod through two fifth lugs, the second inner cylinder is hinged with a third pedal mounting hole on a third pedal through a sixth lug, the other end of the third pedal is arranged towards the second ejector rod, one end of the first supporting rod is hinged with a third supporting rod mounting hole on the first end of the second supporting rod through the first supporting rod mounting hole, the first supporting rod and the second supporting rod is hinged with the other end of the second supporting rod, the first inner cylinder can rotate upwards along with the second pedal, the second pedal can rotate, and the second pedal can rotate upwards along with the second pedal is folded, the second pedal can rotate, and the other end of the second pedal can rotate upwards rotate along with the second pedal is folded up to the second pedal, and the second pedal can rotate, and the first pedal can rotate upwards rotate along with the second pedal can rotate, when the guiding edge strip on the third pedal contacts with the flange strip on the first pedal, the guiding edge strip can jack up the flange strip on the first pedal, so that the first pedal is driven to rotate around the first pedal mounting hole.

5. The step-collapsible built-in gate according to any one of claims 3 or 4, wherein: the width of the notch of the groove is larger than that of the first pedal and smaller than the outline width of the flange strip.

6. The step-foldable built-in boarding ladder of claim 1, wherein: the first supporting rod and the second supporting rod are semicircular at two ends and have a rectangular middle part.

7. The step-foldable built-in boarding ladder of claim 1, wherein: the hole spacing of the first stay bar mounting holes and the second stay bar mounting holes on the two ends of the first stay bar is larger than the hole spacing of the third stay bar mounting holes and the fourth stay bar mounting holes on the two ends of the second stay bar, and the distance difference of the hole spacing of the first stay bar mounting holes and the second stay bar mounting holes is coordinated with the distance between the third lug and the fifth lug when the boarding ladder is in a beam-contracting state.

8. The step-foldable built-in boarding ladder of claim 1, wherein: the first pedal, the second pedal and the third pedal are all located the urceolus both sides when installing, and first pedal and third pedal are located the urceolus left side, and first pedal is located third pedal upper end, and the second pedal is located the urceolus right side.