Background
See fig. 1. Fig. 1 shows a schematic view of a conventional boarding bridge leveling mechanism. As shown in fig. 1, a conventional boarding bridge leveling mechanism 10 includes a driving device 11, a swing link 12, a driving lever 13, a first detection switch 14, and a leveling wheel 15. The driving device 11 is installed on the boarding bridge 100 (see fig. 2), one end of the swing link 12 is hinged to the driving device 11, the other end is hinged to one end of the active lever 13, and the other end of the active lever 13 is installed with the first detection switch 14 and the leveling wheel 15. The levelling wheel 15 may be a rubber wheel.
When the boarding bridge 100 is abutted to the airplane, the driving device 11 drives the swing rod 12 to drive the driving rod 13 to move, so that the leveling wheels 15 are contacted and pressed on the airplane body with a certain pressure, when passengers get on or off the airplane or load or unload goods, the airplane body can ascend or descend, and due to a certain pressure between the leveling wheels 15 and the airplane body, during the ascent or descent of the aircraft body, the leveling wheels 15 roll on the aircraft body, and since the leveling wheels 15 are connected to the first detection switch 14, the first detection switch 14 can detect a signal that the leveling wheels 15 rotate with respect to the active lever 13, and provides the detected signal to a PLC, which calculates a distance of ascending or descending of the airplane body according to the received signal, and controls the front end of the boarding bridge 100 to ascend or descend along with the airplane body, so that the boarding bridge is always kept in contact with the airplane body at a proper height position.
See fig. 2. Fig. 2 is a schematic diagram showing a comparison between an initial position where the boarding bridge abuts against the airplane and a position after the boarding bridge is lifted. As shown in fig. 2, the boarding bridge 100 is hinged at its rear end to a fixed structure such as a terminal 200, and the boarding bridge 100 can be extended and retracted forward and backward so that its front end can abut against the fuselage of the airplane. As described above, when the aircraft body ascends or descends, the PLC controls the front end of the boarding bridge 100 to ascend or descend accordingly. However, in the conventional configuration of the boarding bridge 100, the front end of the boarding bridge 100 expands and contracts forward and backward at the same time when it is raised or lowered, and as shown in fig. 2, the boarding bridge 100 is displaced by Δ L in the horizontal direction from the initial position after the front end of the boarding bridge 100 is raised. Once the front end of the boarding bridge 100 horizontally displaces, the hinge point between the driving rod 13 and the swing rod 12 of the leveling mechanism moves back and forth, and the leveling wheel 15 of the leveling mechanism is always pressed on the airplane body, so that the back and forth movement of the hinge point between the driving rod 13 and the swing rod 12 inevitably causes the leveling wheel 15 to roll up and down on the airplane body, and the up and down rolling of the leveling wheel 15 means that the leveling wheel 15 rotates relative to the driving rod 13. This relative rotation is detected by the detection device mounted on the active lever 13, so that the PLC erroneously determines that the aircraft body is floating up and down, thereby causing a detection error.
Referring to fig. 3, fig. 3 shows a schematic diagram of a verification error due to a change in the angle of an active lever in a leveling mechanism. As shown in fig. 3, the front end of the boarding bridge 100 is telescopically displaced G in the horizontal direction, during which one end of the active lever 13 is changed from an initial position (see solid line) to a position away from the airplane (see dotted line) and an included angle variation α is generated, while the other end of the active lever 13 is displaced H in the vertical direction, corresponding to the leveling wheels 15 moving up and down a distance along the airplane body. Therefore, the front-back expansion change of the front end of the boarding bridge 100 in the horizontal direction drives the hinge point of the lower end part of the driving rod 13 to move back and forth, the angle of the driving rod 13 relative to the leveling wheel 15 correspondingly changes, and the change is detected by the detection device arranged on the driving rod 13, so that the PLC misjudges that the leveling wheel 15 moves up and down on the airplane body, and the detection error is caused.
Referring to fig. 4, fig. 4 shows a detection error curve of a conventional boarding bridge leveling mechanism. As can be seen in fig. 4: as the retraction distance of the tip end portion of the boarding bridge 100 increases (becomes more and more distant from the airplane), the detection error curve caused by the change in the horizontal distance shows a steep upward trend, which means that the detection error caused by the change in the horizontal distance increases sharply as the retraction distance of the tip end portion of the boarding bridge 100 increases; meanwhile, as shown in fig. 4, as the retraction distance of the tip end of the boarding bridge 100 increases, the detection error curve caused by the angle change of the active lever 13 also shows an upward trend, that is, the detection error caused by the angle change of the active lever 13 also gradually increases as the retraction distance of the tip end of the boarding bridge 100 increases, and since the total detection error is the sum of the detection error caused by the change of the horizontal distance and the detection error caused by the change of the angle, the total detection error sharply increases as the retraction distance of the tip end of the boarding bridge 100 increases. Therefore, the existing boarding bridge leveling mechanism can cause larger detection error in the mechanical principle, thereby endangering the safety of the airplane.
From the above analysis, it can be determined that such detection errors can be avoided if the leveling wheels 15 of the boarding bridge leveling mechanism can also make forward and backward telescopic linear motions along with the boarding bridge. Generally, the mechanism for realizing the front-back telescopic linear motion of the leveling wheels 15 needs to be applied to a guide rail, a sliding block or a roller, but in practical application, because the aircraft body has a certain radian, when the aircraft ascends or descends, an upward or downward component force is given to the mechanism for the linear motion, and the force easily causes the linear motion to be blocked or the guide rail to be deformed, so the mechanism is unreliable.
In addition, in the conventional boarding bridge leveling mechanism, the first detection switch 14 is a limit switch or an encoder, and the detection precision is not high enough.
The above information disclosed in this background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not constitute prior art that is already known to a person of ordinary skill in the art.
Detailed Description
Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their detailed description will be omitted.
The invention relates to a boarding bridge leveling mechanism, which comprises the following steps: the movement track of the leveling wheel in the extension and retraction process of the boarding bridge is changed by installing the leveling wheel on a four-bar mechanism, so that the movement track of the leveling wheel is approximately linear. That is, the present invention reduces the displacement of the leveling wheel in the up-and-down direction during the extension and contraction of the boarding bridge by mounting the leveling wheel on a four-bar linkage. Therefore, the boarding bridge leveling mechanism can effectively reduce the detection error caused by the extension and contraction of the boarding bridge and mistakenly considering that the airplane is lifted.
Referring to fig. 5A and 5B, fig. 5A is a schematic perspective view illustrating an opened state of a leveling mechanism of a boarding bridge according to an exemplary embodiment of the present invention; fig. 5B is a front view showing a state where the boarding bridge leveling mechanism shown in fig. 5A is in contact with the airplane body 500. The invention relates to a leveling mechanism of a boarding bridge, which is arranged on the boarding bridge and used for controlling the front end part of the boarding bridge to ascend or descend along with an airplane body so as to ensure that the boarding bridge always keeps a proper position close to the airplane body.
As shown in fig. 5A and 5B, an embodiment of the boarding bridge leveling mechanism of the present invention includes: the mounting seat 2, the driving rod 31, the driven rod 32, the mounting rod 33, the driving device 41, the traction rod 34 and the extension spring 51. The mount 2, the driving link 31, the driven link 32, and the mounting link 33 may form a four-bar linkage, and the mounting link 33 is in a state of extending to the outside of the four-bar linkage.
The mounting seat 2 can be fixedly mounted to the side of the front end of the boarding bridge. The active lever 31 is hinged at its lower part to the mounting 2 adjacent to its lower end. The lower end portion of the driven lever 32 is hinged to the mount 2, and the driven lever 32 is located above the driving lever 31. One end of the mounting lever 33 is hinged to the upper end of the driven lever 32, and the other end is mounted with the first detection switch 6 and the leveling wheel 7. The first detection switch 6 can be, for example, a limit switch or an encoder, the arrangement of which on the levelling wheel 7 can be the same as in the prior art. At least one of the driving link 31, the driven link 32 and the mounting link 33 may have a hollow tubular shape, which may reduce costs.
The driving device 41 is mounted on the mounting base 2 and can drive the lower end portion of the driving rod 31 to rotate around a hinge point of the driving rod and the mounting base 2. The specific structure of the driving device 41 can be various, such as an air cylinder, an oil cylinder, a motor, a gear-rack mechanism, a motor, a worm-gear mechanism, a motor, a screw-nut mechanism, and the like. The main function of the driving device 41 is to automatically retract the boarding bridge leveling mechanism of the present invention. In other embodiments, the drive device is not provided, and the boarding bridge leveling mechanism is manually collected or does not need to be collected.
The traction rod 34 has one end connected to the lower portion of the active rod 31 and the other end connected to the driving device 41, and the traction rod 34 may be rigid or flexible. In other embodiments, the pull rod 34 may not be provided.
One end of the tension spring 51 is connected to the lower end of the active lever 31, and the other end is connected to the mount 2. The tension spring 51 has a pre-tightening force, and under the action of the pre-tightening force, the leveling wheels 7 of the boarding bridge leveling mechanism always keep the tendency of extending outwards, so that the boarding bridge leveling mechanism can contact the airplane body 500 with a certain pressure, and the contact between the leveling wheels 7 and the airplane body 500 is more reliable. In other embodiments, the extension spring 51 can be replaced by other pre-tightening devices, such as a compression spring, a torsion spring, a counterweight device, a constant torque motor, a rubber member with elasticity, and the like.
The upper end portion of the active lever 31 is hinged to the mounting lever 33. In another embodiment, the upper end of the driving link 31 is adjacent to the hinge point B of the mounting link 33 and the driven link 32 at the position of the hinge point C of the mounting link 33, that is, the upper end of the driving link 31 is between the length midpoint a of the mounting link 33 and the hinge point B of the mounting link 33 and the driven link 32 at the position of the hinge point C of the mounting link 33. Further, the distance between the upper end portion of the driving link 31 at the hinge point C of the mounting link 33 to the hinge point B of the mounting link 33 and the driven link 32 is less than or equal to 1/4 of the entire length of the mounting link 33.
One side surface of the active lever 31 facing the mounting lever 33 is an inclined surface 311, and the inclined surface 311 is in contact with the mounting lever 33 in the stowed state of the boarding bridge leveling mechanism. Therefore, the volume of the boarding bridge leveling mechanism can be reduced when the boarding bridge leveling mechanism is folded.
The length ratio of the driving rod 31, the driven rod 32 and the mounting rod 33 can be varied from (1.1-1.3) to (0.9-1.1) to (1.1-1.3), for example, the length ratio of the driving rod 31, the driven rod 32 and the mounting rod 33 can be 1.2:1:1.2, 1.1:0.9:1.3, 1.3:1.1:1.1, and the like.
The change process of the boarding bridge leveling mechanism from the opening state to the retracting state is described as follows: normally, the boarding bridge levelling mechanism of the invention is in an open state under the action of a pretensioning device, such as a tension spring 51, the open state of the boarding bridge levelling mechanism corresponding to the extended state of the levelling wheels 7. Specifically, the tension spring 51 has a pre-tightening force, which pulls the lower end portion of the driving rod 31, so that the driving rod 31 rotates clockwise around the hinge point D of the driving rod 31 and the mounting seat 2, and the driven rod 32 rotates clockwise around the hinge point F of the driven rod 31 and the mounting rod 33, so that the driving rod 31 pushes the mounting rod 33 to rotate counterclockwise around the hinge point B of the mounting rod 33 and the driven rod 32, and the leveling wheel 7 mounted at the end portion of the mounting rod 33 extends away from the mounting seat 2 along with the counterclockwise rotation until contacting an obstacle, such as the aircraft body 500, and stops, at this time, due to the action of the tension spring 51, the leveling wheel 7 is pressed onto the aircraft body 500 with a certain pressure. When the boarding bridge leveling mechanism is converted from the open state to the stowed state, the driving device 41 drives the lower end part of the driving rod 31, and the driving force of the driving device 41 can overcome the acting force of the extension spring 51, so that the driving rod 31 rotates around the hinge point D of the driving rod 31 and the mounting seat 2 anticlockwise, the driven rod 32 rotates around the hinge point F of the driven rod 32 anticlockwise, the driving rod 31 pulls the mounting rod 33 to rotate around the hinge point B of the mounting rod 33 and the driven rod 32 clockwise, the leveling wheels 7 mounted at the end parts of the mounting rod 33 rotate clockwise to retract towards the mounting seat 2 until the mounting rod 33 is attached to the inclined surface 311 of the driving rod 31, and the boarding bridge leveling mechanism is in a fully retracted state.
In the boarding bridge leveling mechanism, the mounting seat 2, the driving rod 31, the driven rod 32 and the mounting rod 33 form a four-bar mechanism, and the four-bar mechanism can be folded and unfolded freely and smoothly and is not easy to generate a clamping stagnation phenomenon, so that the leveling wheels 7 driven by the four-bar mechanism can be changed very smoothly between an extending state (corresponding to the opening state of the boarding bridge leveling mechanism) and a retracting state (corresponding to the folding state of the boarding bridge leveling mechanism).
Referring to fig. 5C, fig. 5C is a schematic diagram illustrating a movement trace of a leveling wheel in the boarding bridge leveling mechanism shown in fig. 5A. As shown in fig. 5C, in the boarding bridge leveling mechanism of the present invention, the movement locus S of the leveling wheels 7 is in an approximately straight shape. When the airplane body ascends or descends, the front end part of the boarding bridge ascends or descends along with the airplane body, the front end part of the boarding bridge generates horizontal displacement in the horizontal direction, at this time, although the hinge points D, F in the leveling mechanism of the boarding bridge generate horizontal displacement with corresponding magnitude in the horizontal direction respectively, the driving rod 31 and the driven rod 32 in the leveling mechanism of the boarding bridge can rotate along the clockwise direction or the anticlockwise direction simultaneously, the driving rod 31 pushes or pulls the mounting rod 33 to rotate towards the direction opposite to the rotating direction of the driving rod 31, so that the leveling wheels 7 mounted at the ends of the mounting rod 33 are pushed to have larger displacement in the horizontal direction, but the displacement of the leveling wheels 7 in the up and down direction is very small or even 0, so that the approximately straight-line-shaped motion track S of the leveling wheels 7 is formed. That is, in the present invention, since the leveling wheel 7 is mounted on one of the rods of a four-bar linkage, the horizontal displacement of the hinge point D, F does not directly result in a large vertical displacement of the leveling wheel 7, and after the four-bar linkage is switched, the horizontal displacement of the hinge point D, F only results in a small vertical displacement of the leveling wheel 7, even a vertical displacement of the leveling wheel 7 is 0.
Referring to fig. 5D, in the boarding bridge leveling mechanism of the present invention, the motion trajectory of the leveling wheel 7 is approximately linear, and the displacement of the front end of the boarding bridge in the horizontal direction (the horizontal displacement of the hinge point D, F) only causes the leveling wheel 7 to generate a small displacement or no displacement in the vertical direction, so that the boarding bridge leveling mechanism of the present invention can significantly reduce the detection error caused by the horizontal displacement of the front end of the boarding bridge. As shown in fig. 5D, as the retraction distance of the front end of the boarding bridge 100 increases (becomes farther away from the aircraft), an error curve caused by the change in the horizontal distance is wavy, a part of the curve is located above the coordinate axis, and a part of the curve is located below the coordinate axis, that is, in the present invention, the detection error caused by the change in the horizontal distance shows a fluctuation change in the vertical direction as the retraction distance of the front end of the boarding bridge 100 increases; further, as shown in fig. 5D, as the retraction distance of the front end portion of the boarding bridge 100 increases, the detection error curve due to the change in the angle of the mounting rod 33 tends to rise slowly, that is, as the retraction distance of the front end portion of the boarding bridge 100 increases, the detection error due to the change in the angle of the mounting rod increases only slowly, not sharply. As shown in fig. 5D, in the present invention, as the distance of the boarding bridge from the airplane increases, the total detection error curve is in a wave shape, that is, the total detection error fluctuates up and down within a small range of amplitude, rather than continuously increasing, so that the detection accuracy of the boarding bridge leveling mechanism of the present invention is high.
In another embodiment, the mounting seat 2 has an inclined plate portion, a hollow portion and an opening. The driven rod 32 and the driving rod 31 are hinged to the upper end and the lower end of the inclined plate respectively, the lower end of the driving rod 31 extends into the hollow portion from the opening, and the driving device 41 is mounted in the hollow portion. Therefore, the boarding bridge leveling mechanism is very attractive, the mounting seat 2 also has a protection effect on the driving device 41, and the service life of the boarding bridge leveling mechanism is prolonged. In detail, as shown in fig. 5A and 5B, the mounting base 2 may be in the shape of a box with an opening 20, and the box may be formed by fixedly connecting a top plate 21, a bottom plate 22, two side plates 23, a front plate 24 and a rear plate 25, which surround the hollow portion. The front plate 24 may constitute the inclined plate portion, and the opening 20 is formed between the lower end portion of the front plate 24 and the bottom plate 22. The lower end of the driven rod 32 is hinged with the upper end of the front plate 24, the lower end of the driving rod 31 is hinged with the lower end of the front plate 24, and the lower end of the driving rod 31 extends into the hollow part from the opening 20. The driving device 41 is, for example, an air cylinder or an oil cylinder, a cylinder body of the air cylinder or the oil cylinder is mounted on the rear plate 25, a piston rod of the air cylinder or the oil cylinder can be hinged to the lower end portion of the traction rod 34, and when the piston rod extends out of the cylinder body, the piston rod can contact and push the lower end portion of the active rod 31 and can push the active rod 31 to rotate around a hinge point D of the active rod 31 and the front plate 24.
The above description of mount 2 and drive device 41 is exemplary only and not intended to limit the present invention, and other configurations of mount 2 and drive device 41 are also applicable to the present invention.
Referring to fig. 6A and 6B, fig. 6A is a schematic perspective view of an exemplary boarding bridge leveling mechanism of the present invention, wherein the boarding bridge leveling mechanism is housed in a housing assembly 8; fig. 6B is a schematic perspective view of the boarding bridge leveling mechanism shown in fig. 6A, wherein the leveling wheels extend out of the housing assembly 8. As shown in fig. 6A and 6B, in another embodiment, the boarding bridge leveling mechanism of the present invention further includes a housing assembly 8, and when the boarding bridge leveling mechanism is in a retracted state, the boarding bridge leveling mechanism can be accommodated in the housing assembly 8 and protected from external adverse factors such as rain, wind, sand, etc.
The housing assembly 8 includes a stationary housing 81, a left opening door 82 and a right opening door 83. The fixed cover 81 is fixed on the mounting base 2 and has an accommodating space and an opening; one side of the left opening door 82 is hinged to one side of the opening of the fixed cover body 81; one side of the right opening door 83 is hinged to the other side of the opening of the fixed cover 81, and the left opening door 82 and the right opening door 83 can close the opening in a closed state. When the left opening door 82 and the right opening door 83 are in a closed state, the fixed cover 81, the left opening door 82 and the right opening door 83 jointly form a closed chamber, and the boarding bridge leveling mechanism can be contained in the closed chamber in a retracted state. By opening the left-hand door 82 and the right-hand door 83, parts of the follower lever 32, the mounting lever 33 and the levelling wheels 7 of the boarding bridge levelling mechanism can be extended out of the housing assembly 8.
Referring to fig. 6C and 6D, fig. 6C shows a schematic partial view of the boarding bridge leveling mechanism shown in fig. 6A taken along plane E-E, showing the closure of the cover assembly 8; fig. 6D shows a schematic sectional view of the boarding bridge leveling mechanism shown in fig. 6B, taken along plane F-F, showing the cover assembly 8 in an open state. In another embodiment, the housing assembly 8 further comprises at least two torsion springs 84, at least two stoppers 85, and a door opening mechanism. At least one torsion spring 84 is arranged at the joint of the left opening door 82 and the fixed cover 81, at least one torsion spring 84 is arranged at the joint of the right opening door 83 and the fixed cover 81, and the torsion force of the torsion springs 84 keeps the opening tendency of the left opening door 82 and the right opening door 83, namely, the torsion force of the torsion springs 84 keeps the left opening door 82 and the right opening door 83 in an opening state under the action of no external force. At least two limiting members 85 are respectively used for limiting the maximum opening angle of the left opening door 82 and the right opening door 83. It should be noted that the limiting member 85 is not necessarily used in the present invention, and the limiting member 85 may be omitted when the maximum opening angle of the left opening door 82 and the right opening door 83 is not limited. The door opening mechanism is for automatically opening or closing the left opening door 82 and the right opening door 83. The left door 82 and the right door 83 may be manually opened without the door opening mechanism.
In another embodiment, the door opening mechanism in the housing assembly 8 includes a stop bar 86 and two stop plates 87. The stopper rod 86 is fixed to the mounting rod 33, and both ends of the stopper rod 86 extend out of the mounting rod 33. The restraint bar 86 may be fixed vertically to the mounting bar 33 or may be inclined at an acute angle with respect to the mounting bar 33. Two stopper plates 87 are fixed to the inner sides of the left opening door 82 and the right opening door 83, respectively, and each stopper plate 87 has a stopper portion 871 protruding inward. When the boarding bridge leveling mechanism is converted from the open state to the retracted state, the two end parts of the limit rod 86 respectively press the two limit parts 871 so as to drive the left opening door 82 and the right opening door 83 to rotate inwards to be closed.
Furthermore, two ends of the limit rod 86 are respectively provided with a bump 861, and the two bump 861s press the two limit parts to drive the left opening door 82 and the right opening door 83 to be closed. The striker 861 may be formed integrally with the stopper rod 86, or may be a separate structure such as a bolt attached to the stopper rod 86.
In another embodiment, the limiting portion 871 is provided with a through hole, the fixing cover 81 is provided with a fixing plate 811 corresponding to the position of the limiting plate 87, the fixing plate 811 is provided with a through hole, the limiting member 85 is a rod, such as a limiting pin or a limiting bolt, for example, which is inserted through the through hole of the limiting portion 871 and the through hole of the fixing plate 811, and the top end of the rod is provided with a limiting cap to prevent the rod from falling through the two through holes. Of course, the present invention is not limited thereto, and other ways of preventing the rod from falling may be applied to the present invention. In another embodiment, the limiting portion 871 is provided with a through hole, the opening of the fixing cover 81 is provided with a flange 810, the flange 810 is provided with a through hole, the limiting member 85 is a rod member such as a limiting pin or a limiting bolt, the rod member penetrates through the through hole of the limiting portion 871 and the through hole of the flange 810, and the top end of the rod member is provided with a limiting cap or other structures capable of preventing the rod member from falling.
In another embodiment, the boarding bridge leveling mechanism of the present invention further comprises a detection assembly for detecting whether the leveling wheels 7 contact the aircraft fuselage. The invention discloses a detection assembly, which mainly comprises an elastic piece and a second detection switch. The elastic piece is connected between the leveling wheel and the mounting rod; the second detection switch is mounted on the mounting rod. When the leveling wheel does not contact the airplane body, the elastic piece enables the second detection switch not to be triggered; when the leveling wheel is contacted with and pressed on the airplane body, the reaction force of the airplane body on the leveling wheel can trigger the second detection switch, and the second detection switch sends out a trigger signal. Various embodiments of the detection assembly of the present invention are described in detail below.
Referring to fig. 5A, 7B and 7C, fig. 7A shows a schematic sectional view of the boarding bridge leveling mechanism shown in fig. 5A taken along the plane G-G, showing the structure of a detection assembly; fig. 7B and 7C are schematic sectional views of the boarding bridge leveling mechanism shown in fig. 5A, taken along the plane H-H, showing a state where the leveling wheels are not in contact with the aircraft and a state where the leveling wheels are in contact with the aircraft, respectively.
As shown in fig. 5A and 7A, in an embodiment of the detecting assembly of the present invention, the mounting rod 33 in the boarding bridge leveling mechanism has an upper side 331 and a lower side 332 opposite to each other. The boarding bridge leveling mechanism further comprises a leveling wheel seat 71, and the leveling wheel 7 is installed on the leveling wheel seat 71. The leveling wheel base 71 has an upper side 711 and a lower side 712 opposite thereto. The upper side 711 of the leveling wheel seat 71 is hinged with the upper side 331 of the mounting rod 33 through a hinge 710, a compression spring 72 is installed between the lower side 712 of the leveling wheel seat 71 and the lower side 332 of the mounting rod 33, and the compression spring 72 can also be replaced by other elastic structures such as a compressed rubber strip and the like.
In this embodiment, the detection assembly includes a second detection switch 73 mounted on the leveling wheel base 71 and an engagement piece 74 mounted on the mounting rod 33. The engagement member 74 may be a partial structure of the mounting rod 33, or may be a plate member mounted to the mounting rod 33 (see fig. 7A).
Referring to fig. 7A, in a natural state, i.e., when the leveling wheel 7 is not subjected to an external force such as a pressure of the aircraft body, the center line of the leveling wheel seat 71 and the center line of the mounting rod 33 may be on the same straight line; under the action of the biasing force of the compression spring 72, the center line of the leveling wheel seat 71 and the center line of the mounting rod 33 may not be aligned and form an obtuse angle.
Referring to fig. 7B and 7C, in the case where the leveling wheel 7 is in contact with and pressed against the aircraft body, the aircraft body has a reaction force to the leveling wheel 7, which causes the leveling wheel 7 and the leveling wheel base 71 to rotate counterclockwise through an angle, for example, through 5 ° about the hinge axis 7100 of the leveling wheel base 71 and the mounting rod 33, and the mating member 74 triggers the second detection switch 73. The second detection switch 73 may be a contact type detection switch, and in this case, the second detection switch 73 may be triggered when contacting the mating member 74; the second detection switch 73 may be a proximity type detection switch such as a stroke switch, and in this case, the second detection switch 73 may be triggered when it approaches the mating member 74. The signal triggered by the second detection switch 73 can be transmitted to the control room of the boarding bridge leveling mechanism under the control of the controller, so that the operator of the boarding bridge leveling mechanism can know that the leveling wheels 7 contact and press the airplane body, wherein the controller can be a PLC controller. In this embodiment, the angle of counterclockwise rotation of the leveling wheel base 71 about the hinge axis 7100 of the leveling wheel base 71 and the mounting bar 33 is not limited to 5 °, and is generally feasible within the range of 3 ° to 10 °.
Referring to fig. 6B and 8, fig. 8 shows a K-direction view of fig. 6B, showing a structure of another detecting member. The boarding bridge leveling mechanism of this embodiment further includes a support 91, a bracket 92, and a tension spring 93.
The support 91 is fixed on the end part of the mounting rod 33, and the support 91 has a certain height; one end of the bracket 92 is provided with the leveling wheel 7, and the other end is rotatably connected to the support 91 through a pin shaft 911 and other structures; one end of the extension spring 93 is connected to the bracket 92, and the other end is connected to the support 91, for example, the other end of the extension spring 93 is hung in a hole 912 on the support 91, the hole 912 is located above the pin 911, and the extension spring 93 is located above the bracket 92.
In the boarding bridge leveling mechanism of this embodiment, the detection unit includes a second detection switch 94 attached to the end of the mounting rod 33.
When the leveling wheel 7 is in contact with and pressed against the airplane body, the reaction force of the airplane body on the leveling wheel 7 can enable the leveling wheel 7 to rotate anticlockwise through an angle of 6 degrees, for example, around a hinge point of the support 92 and the support 91 together with the support 92, the support 92 triggers the second detection switch 94, and the second detection switch 94 sends a triggering signal. It is generally possible for the bracket 92 to be rotated counterclockwise through an angle in the range of 5 deg. to 10 deg. about the hinge point of the bracket 92 with the holder 91. The second detection switch 94 in this embodiment may be a contact type detection switch or a proximity type detection switch, similar to the second detection switch 73 shown in fig. 7A.
Further, in the present embodiment, the detecting assembly may further include a limiting member 95, such as a limiting pin or a limiting screw. The limiting member 95 is mounted on the support 91, the limiting member 95 may be mounted between the pin 911 and the hole 912, and the limiting member 95 may be closer to the bracket 92.
Of course, it should be understood by those skilled in the art that the position limiting member 95 in the detecting assembly is not limited to a limiting pin or a limiting screw, and the installation position of the position limiting member 95 is not limited to be above the support 91, so long as the position limiting structure can prevent the bracket 92 from rotating clockwise.
Referring to fig. 5B, the structure of another detection assembly in the boarding bridge leveling mechanism of the present invention is shown. As shown in fig. 5B, the detection assembly of this embodiment is suitable for the case where the boarding bridge leveling mechanism is provided with a drawbar 34. A recess 341 may be provided in the drawbar 34. The detecting member of this embodiment includes a second detecting switch 90, and the second detecting switch 90 is installed at a position corresponding to the concave portion 341 at the lower end of the active lever 31. The second detection switch 90 may be a contact type switch or a proximity type switch, and when the second detection switch 90 is in contact with or in proximity to the recessed portion 341, the leveling wheel 7 is not in contact with the aircraft body, and when the second detection switch 90 is away from the recessed portion 341, the second detection switch 90 is triggered to emit a trigger signal.
Further, as can be seen from the description of the conversion process of the front boarding bridge leveling mechanism between the opened state and the stowed state, the stowing of the boarding bridge leveling mechanism is accomplished by driving the lower end portion of the driving lever 31 by the driving device 41. Referring to fig. 5B, taking the driving device 41 as an air cylinder or an oil cylinder as an example, the length of the piston rod extending out of the cylinder has a certain influence on whether the leveling wheel 7 can contact the airplane, for example, when the length of the piston rod extending out of the cylinder is too long, the rotation of the active lever 31, i.e., the outward extending action of the leveling wheel 7, is limited. In this case, even if the leveling wheel 7 does not contact the aircraft body as a result of the detection by the detection unit, the leveling wheel 7 cannot be extended outward to contact the aircraft. In the invention, the solution to the problem is as follows: a third detection switch 75 is provided on the drive device 41, and the third detection switch 75 is used to detect the shortest length of the drive device 41. In the case that the driving device 41 is a cylinder or a cylinder, the third detection switch 75 (see fig. 5B) detects the limit position of the piston rod that can be retracted into the cylinder, and when the piston rod is retracted into the limit position, the third detection switch 75 is triggered to send out a trigger signal.
In the boarding bridge leveling mechanism, when the controller receives the trigger signal of the third detection switch 75 and does not receive the trigger signal of the second detection switch of the detection component, the distance between the front end part of the boarding bridge and the airplane body is too far, and at the moment, the controller can send out a prompt signal, and an operator can control the boarding bridge to further extend out for a certain distance towards the airplane direction according to the prompt signal; or the controller directly controls the boarding bridge to further extend a certain distance towards the airplane direction according to the prompt signal.
The boarding bridge comprises a telescopic boarding bridge body and at least one boarding bridge leveling mechanism arranged at the front end part of the boarding bridge body, and usually, one boarding bridge leveling mechanism can be respectively arranged at two sides of the front end part of the boarding bridge body. The boarding bridge leveling mechanism is the boarding bridge leveling mechanism.
Relative terms, such as "upper" or "lower," may be used in the above embodiments to describe one component of an icon relative to another component. It will be understood that if the device illustrated in the drawings is turned over with its top and bottom reversed, elements described as "upper" or "lower" will be referred to as "lower" or "upper". The terms "a," "an," "the," and "at least one" are used to indicate the presence of one or more elements/components/etc. The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements; "first" and "second" are used merely as labels, and are not numerical limitations on their objects.
It is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth herein. The invention is capable of other embodiments and of being practiced and carried out in various ways. The foregoing variations and modifications fall within the scope of the present invention. It will be understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention.
While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.