AU2021107636A4

AU2021107636A4 - A landing gear

Info

Publication number: AU2021107636A4
Application number: AU2021107636A
Authority: AU
Inventors: Zhiqiang Wu; Minrui YANG
Original assignee: Guangdong Fuwa Heavy Industry Co Ltd
Current assignee: Guangdong Fuwa Heavy Industry Co Ltd
Priority date: 2020-05-28
Filing date: 2021-12-06
Publication date: 2022-01-20
Anticipated expiration: 2028-08-06

Abstract

A landing gear, comprising an inner leg, an outer leg, a nut, a screw rod and a transmission mechanism. The transmission mechanism comprises a transmission shaft, a first driven gear and a movable rod. The transmission shaft is installed with a first transmission gear and a second transmission gear. The screw rod is installed with a second driven gear. Both the second transmission gear and the second driven gear mesh with the first driven gear. The first driven gear is provided with a first mating part, and the movable rod is provided with a driving gear and a second mating part. The movable rod is inserted into the outer leg and can move between a first position close to the first driven gear and a second position distant to the first driven gear. When the movable rod is at the first position, the driving gear is separated from the first transmission gear and the first matching part cooperates with the second matching part. When the movable rod is at the second position, the first matching part is separated from the second matching part and the driving gear is meshed with the first transmission gear. The present application can realize the switch between the fast gear and slow gear of the lifting of the landing gear with advantages of a simple structure and a small space occupation. 1/3 51 50 322 12 3a 14 13 FIG. 1

Description

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FIG. 1

A LANDING GEAR CROSS-REFERENCE TO RELATED APPPLICATION

[0001] The content of International Patent Application No. PCT/CN2020/107376 is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The present invention relates to the technical field of vehicle accessories, in particular to a landing gear.

BACKGROUND

[0003] Landing gears are usually used to support semi-trailers. When a trailer is separated from a tractor, a landing gear provides necessary support for the trailer. A conventional landing gear generally includes an inner leg, an outer leg, a screw rod and a nut. The nut is installed on the inner leg, the screw rod is threaded on the nut, and the screw rod is driven to rotate by the transmission mechanism installed on the outer leg, and then the inner leg and outer leg are extended or retracted through the screw rod-nut mechanism, wherein the transmission mechanism is conventionally a gear transmission mechanism that power is transmitted to a screw rod by an external handle. The conventional landing gears provide only one lifting speed for the landing gears, which complicates the adjustment process, and it is impossible to accurately adjust the lifting height of the landing gears.

[0004] In order to overcome the shortcomings of the conventional landing gears, the internal transmission mechanism of some landing gears can be shifted as needed. When the height of the landing gears needs to be adjusted quickly, the transmission mechanism should be shifted to the "fast gear". When precise height needed, the transmission mechanism should be shifted to "slow gear". The structure of this transmission mechanism is often more complicated and takes up more space inside the landing gears.

SUMMARY OF THE INVENTION

[0005] To overcome the shortcomings mentioned above, an object of the present application is to provide a landing gear, which can realize the switching between the fast and the slow height adjustment of the landing gear, and has advantages of a simple structure and a small space occupation.

[0006] To realize the above purpose, the invention adopts the following technical solutions:

[0007] The present application relating to a landing gear includes an inner leg, an outer leg sleeved outside the inner leg, a nut installed on the inner leg, a screw rod threaded through the nut and screwed on the nut, and a transmission mechanism installed on the outer leg. The transmission mechanism includes a transmission shaft pivotally connected to the outer leg, a first driven gear pivotally connected to the outer leg, and a movable rod. One end of the transmission shaft is installed with a first transmission gear and the other end is installed with a second transmission gear. The screw rod is installed with a second driven gear. The first driven gear is located between the second transmission gear and the second driven gear. Both the second transmission gear and the second driven gear mesh with the first driven gear. The first driven gear is provided with a first mating part, and the movable rod is provided with a driving gear and a second mating part matching the first mating part. The movable rod is inserted into the outer leg and can move between a first position close to the first driven gear and a second position distant to the first driven gear. When the movable rod is at the first position, the driving gear is separated from the first transmission gear and the first matching part cooperates with the second matching part to connect the movable rod to the first driven gear synchronously. When the movable rod is at the second position, the first matching part is separated from the second matching part and the driving gear is meshed with the first transmission gear.

[0008] The first mating part is a plurality of first convex teeth arranged on the first driven gear, and the second mating part is a plurality of second convex teeth arranged on the inner end of the movable rod. The second convex teeth can engage or separate with the first convex teeth when the movable rod moves laterally.

[0009] Guiding slopes are respectively provided on both sides of the ends of the first convex teeth and the second convex teeth.

[0010] The second driven gear is a bevel gear, and the first driven gear is provided with a bevel tooth surface meshing with the bevel gear and a straight tooth surface meshing with the second transmission gear.

[0011] The diameter of the first transmission gear is greater than that of the second transmission gear.

[0012] A pivot is pivotally connected to the outer leg, the first driven gear is synchronously connected to the pivot, and the axis of the pivot is coincident with that of the movable rod.

[0013] The movable rod is provided with a slot extending outward from the inner end surface thereof, and an inserting end is provided on the inner end of the pivot. When the movable rod is at the first position, the inserting end is inserted into the slot.

[0014] A shaft sleeve is fixed on the outer leg, and the movable rod passes through the shaft sleeve.

[0015] A clamping component is also provided between the shaft sleeve and the movable rod, which is used to clamp the movable rod at the first position or the second position.

[0016] The clamping component includes a steel ball and a spring, amounting groove is provided on the movable rod along its radial direction, the spring is located in the mounting groove, and the steel ball is located at the outer end of the spring. The spring is used for pushing the steel ball outward. The inner wall of the sleeve is provided with two annular grooves. When the movable rod is at the first position, the steel ball is embedded in one of the annular grooves, and when the movable rod is at the second position, the steel ball is embedded in the other annular groove.

[0017] The beneficial effects of the invention areas follows:

[0018] Compared with the prior art, the movable rod and the first driven gear of the present application can be connected or disconnected by pushing or pulling the rotating rod laterally, which will change the power transmission sequence of the gears of the transmission mechanism on the outer leg, thereby realizing the switch between the fast gear and slow gear of the lifting of the landing gear. At the same time, the present application has advantages of a simple structure and a small space occupation.

BRIEF DESCRIPTION OF DRAWINGS

[0019] FIG. 1 is a structural diagram of some embodiment according to the present application;

[0020] FIG. 2 is a cross-sectional view of some embodiment according to the present application, which also illustrates a working state of some embodiment;

[0021] FIG. 3 is a schematic diagram of another working state of some embodiment according to the present application.

DETAILED DESCRIPTION

[0022] Hereinafter, the present application will be further described with reference to the figures and specific embodiments:

[0023] As shown in Fig.1 and Fig.2, a landing gear of some embodiment according to the present application includes an inner leg 20, an outer leg 10, a nut 21, a screw rod 11 and a transmission mechanism, wherein the outer leg 10 is sleeved outside of the inner leg 20, both of which form a retractable structure. The nut 21 is fixedly connected to the top end of the inner leg 20. The screw rod 11 extends along the height of the landing gear, passes through the nut 21 and is threaded with the nut 21, and the transmission mechanism is installed on the outer leg 10, which is used to drive the screw rod 11 to rotate, and then drive the nut 21 to move up and down, so that the retractable structure composed of the inner leg 20 and the outer leg 10 is extended or retracted. The transmission mechanism includes a transmission shaft 50, a first driven gear 40 and a movable rod 30, wherein a second driven gear 12 is installed at the top end of the screw rod 11, the transmission shaft 50 extends transversely of the outer leg 10 and pivots with the outer leg 10, a first transmission gear 51 is installed at one end of the transmission shaft 50 and a second transmission gear 52 is installed at the other end, the transmission shaft 50, the first transmission gear 51 and the second transmission gear

52 are all located inside the outer leg 10, the first driven gear 40 is pivotally connected to the outer leg 10 and located inside the outer leg 10, meanwhile the first driven gear 40 is located between the second transmission gear 52 and the second driven gear 12, the second transmission gear 52 and the second driven gear 12 both mesh with the first driven gear 40, and moreover a plurality of convex teeth 41 are provided on the inner side of the first driven gear 40 (i.e., the side facing the inner side of the outer leg 10). The movable rod 30 is inserted into the outer leg 10 laterally from outside to inside, that is, the inner end of the movable rod extends and is located inside of the outer leg 10, and the outer end is located outside of the outer leg 10 to connect the rocker of the landing gear. The movable rod 30 can rotate relative to the outer leg 10 and reciprocate laterally along the outer leg 10. A driving gear 31 is provided on the movable rod 30, and a plurality of convex teeth 32 are provided on the surface of the inner end of the movable rod 30, which are matched with the convex teeth 41. The movable rod 30 can move towards inside the outer leg 10 to a first position against the first driven gear 40, and the movable rod 30 can also move towards outside the outer leg 10 to a second position away from the first driven gear 40, that is, the movable rod 30 can move between the first position and the second position, as shown as Fig.3. When the movable rod moves to the first position, the plurality of convex teeth 32 mesh with the plurality of convex teeth 41, therefore the movable rod 30 and the first driven gear 40 are connected simultaneously, meanwhile the driving gear 31on the movable rod 30 and the first transmission gear 51 are in a separate state, that is, the driving gear 31 is located inside the first transmission gear 51, and at this first position, power can be transmitted between the movable rod 30 and the first driven gear 40. As shown as Fig.2, when the movable rod 30 is at the second position, the driving gear 31 on the movable rod 30 and the first transmission gear 51are in a meshing state, at the same time, the plurality of convex teeth 41 and the plurality of convex teeth 32 are in a separate state, and at this second position, power can be transmitted between the movable rod 30 and the transmission shaft 50 through the driving gear 31 and the first transmission gear 51, while power transmission between the movable rod 30 and the first driven gear 40 is disconnected. Specifically, when the movable rod 30 is placed in the state as shown as Fig.3, the external rocker drives the movable rod 30 to rotate, which in turn drives the first driven gear 40 to rotate, and the first driven gear 40 drives the second driven gear 12 to rotate, and thus realizes the extending and retracting of the inner leg 20 and the outer leg 10. When the movable rod 30 is placed in the state as shown as Fig.2, the external rocker drives the movable rod 30 to rotate, which drives the driving gear 31 and the first transmission gear 51 to drive the transmission shaft 50 to rotate, and then the second transmission gear 52 on the transmission shaft 50 drives the first driven gear 40 to drive the second driven gear 12 to rotate, and finally realizes the extending and retracting of the inner leg 20 and the outer leg 10.

[0024] In the present application, in order to facilitate the smooth engagement of the plurality of convex teeth 32 and the convex teeth 41 when the movable rod 30 is at the first position, inclined surfaces are provided on both sides of the ends of the convex teeth 32 and the convex teeth 41, thus the slot between two adjacent convex teeth 32 has a wider V-shaped opening to facilitate the fitting of the convex teeth 41, and similarly a V-shaped slot is also formed between two adjacent convex teeth 41 to fit the convex teeth 32 when guided by the inclined surface. Even if there is an angular deviation between the movable rod 30 and the first driven gear 40, when the movable rod 30 is pushed laterally, the movable rod 30 can be coupled with the first driven gear 40.

[0025] The convex teeth 32 provided on the inner end of the movable rod 30 and the convex teeth 41 provided on the first driven gear 40 form a clutch structure. When the convex teeth 32 and the convex teeth 41 are engaged, the power is transmitted in the order shown in Fig.3. When the convex teeth 32 and the convex teeth 41 are separated, the power is transmitted in the order shown in Fig. 2. Alternatively, the movable rod 30 and the first driven gear 40 can be respectively provided with matching parts of other structures instead of the convex teeth 32 and the convex teeth 41 to achieve the above functions that as long as the movable rod 30 and the first driven gear 40 can be connected and disconnected when the lateral distance between the movable rod 30 and the first driven gear 40 changes.

[0026] In this embodiment, the second driven gear 12 is a bevel gear, and the first driven gear 40 is provided with a bevel tooth surface 42 and a straight tooth surface 43, wherein the bevel tooth surface 42 meshes with the second driven gear 12 so that the rotation axis of the first driven gear 40 is perpendicular to the central axis of the screw rod 11, and the straight tooth surface 43 meshes with the second transmission gear 52.

[0027] In this embodiment, the diameter of the first transmission gear 51 is greater than that of the second transmission gear 52, so that, in the state shown in Fig.2, the power from the movable rod 30 is transmitted to the first driven gear 40 through the transmission shaft 50, which is used for decelerating and increasing the torque. In this state, it is a slow gear to realize the precise adjustment of the height of the landing gear. The diameter of the driving gear 31 is smaller than that of the first transmission gear 51, and meanwhile the diameter of the second transmission gear 52 is smaller than that of the first driven gear 40, which increases the transmission ratio to improve the adjustment accuracy of the slow gear. As shown in Fig.3, the power from the movable rod 30 is directly transmitted to the first driven gear 40, and the transmission shaft 50 is idling and does not participate in power transmission. In this state, it is a fast gear to realize the rapid adjustment of the height of the landing gear.

[0028] A pivot 44 is pivotally connected to the outer leg 10, which can be mounted on the outer leg 10 through a bearing. The first driven gear 40 is synchronously connected to the pivot 44, and the axis of the pivot 44 is coincident with that of the movable rod 30. During the installation, the first driven gear 40 is mounted from the top of the outer leg 10, and then the pivot 44 is inserted from the side of the outer leg 10 to synchronously connect with the first driven gear 40, which is convenient for the installation of the first driven gear 40. In addition, the movable rod 30 is provided with a slot 301 extending outward from the surface of its inner end, and an inserting end 441 is provided on the inner end of the pivot 44. When the movable rod 30 is at the first position as shown as Fig.3, the inserting end 441 is inserted into the slot 301. In this way, the movable rod 30 and the pivot 44 are connected to ensure that the two have substantially the same coaxiality, so that the power from the movable rod 30 can be effectively transmitted to the first driven gear 40, and meanwhile, the deflection of the first driven gear 40 when driving the second driven gear 12 to rotate can be avoided.

[0029] In some other embodiment, a shaft sleeve 13 is fixed on the outer leg 10, and the movable rod 30 passes through the shaft sleeve 13, which is used to guide the movable rod 30 to move laterally. Meanwhile, A clamping component is also provided between the shaft sleeve 13 and the movable rod 30, which is used to limit the position of the movable rod 30, that is, when the movable rod 30 is at the first position or the second position, the clamping component is used to prevent the movable rod 30 from moving laterally without external lateral pushing or pulling. Specifically, the clamping component includes a steel ball 33 and a spring 34. A mounting groove is provided on the movable rod 30 along its radial direction. The spring 34 is located in the mounting groove, and the steel ball 33 is located at the outer end of the spring 34 and protrudes from the outer surface of the movable rod 30. The steel ball 33 is always pushed toward the outside of the movable rod 30 by the elastic stress of the spring 34. The inner wall of the sleeve 13 is provided with two laterally staggered annular grooves 131. When the movable rod 30 is at the first position, the steel ball 33 is embedded in the annular groove 131 close to the inside of the outer leg 10. When the movable rod 30 is at the second position, the steel ball 33 is embedded in the annular groove 131 close to the outside of the outer leg 10. When the steel ball 33 is embedded in the annular groove 131, rotating the movable rod 30 will make the steel ball 33 slide along the annular groove 131. Thus the movable rod 30 can be rotated to transmit power. Meanwhile, the movable rod 30 is limited by the steel ball 33 embedded in the annular groove 131when no external lateral pushing or pulling. When need to switch between the fast gear and the slow gear, the movable rod 30 is pushed or pulled laterally to make the steel ball 33 squeeze the spring 34 and disengage from the annular groove 131, and then the movable rod 30 can move laterally. Of course, the clamping component is not limited to the above structure composed of the steel ball 33 and the spring 34, which can also be a spring pin or the like.

[0030] Compared with the prior art, the movable rod and the first driven gear of the present application can be connected or disconnected by pushing or pulling the rotating rod laterally, which will change the power transmission sequence of the gears of the transmission mechanism on the outer leg, thereby realizing the switch between the fast gear and slow gear of the lifting of the landing gear. At the same time, the present application has advantages of a simple structure and a small space occupation.

[0031] The above embodiments are only used to illustrate the implementation of the present application, but not to limit it. While the present application has been described with reference to above embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present application. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the present application without departing from the essential scope thereof.

Claims

CLAIMS:

1. A landing gear, wherein the landing gear comprises an inner leg, an outer leg sleeved outside the inner leg, a nut installed on the inner leg, a screw rod threaded through the nut and screwed on the nut, and a transmission mechanism installed on the outer leg; the transmission mechanism comprises a transmission shaft pivotally connected to the outer leg, a first driven gear pivotally connected to the outer leg, and a movable rod; one end of the transmission shaft is installed with a first transmission gear and the other end is installed with a second transmission gear; the screw rod is installed with a second driven gear; the first driven gear is located between the second transmission gear and the second driven gear; both the second transmission gear and the second driven gear mesh with the first driven gear; the first driven gear is provided with a first mating part, and the movable rod is provided with a driving gear and a second mating part matching the first mating part; the movable rod is inserted into the outer leg and can move between a first position close to the first driven gear and a second position distant to the first driven gear; when the movable rod is at the first position, the driving gear is separated from the first transmission gear and the first matching part cooperates with the second matching part to connect the movable rod to the first driven gear synchronously; when the movable rod is at the second position, the first matching part is separated from the second matching part and the driving gear is meshed with the first transmission gear.

2. The landing gear according to claim 1, wherein the first mating part is a plurality of first convex teeth arranged on the first driven gear, the second mating part is a plurality of second convex teeth arranged on the inner end of the movable rod, and the second convex teeth can engage or separate with the first convex teeth when the movable rod moves laterally.

3. The landing gear according to claim 2, wherein inclined surfaces are respectively provided on both sides of the ends of the first convex teeth and the second convex teeth.

4. The landing gear according to claim 1, wherein the second driven gear is a bevel gear and the first driven gear is provided with a bevel tooth surface meshing with the bevel gear and a straight tooth surface meshing with the second transmission gear.

5. The landing gear according to claim 1, wherein the diameter of the first transmission gear is greater than that of the second transmission gear.

6. The landing gear according to claim 1, wherein a pivot is pivotally connected to the outer leg, the first driven gear is synchronously connected to the pivot, and the axis of the pivot coincident with that of the movable rod.

7. The landing gear according to claim 6, wherein the movable rod is provided with a slot extending outward from the inner end surface thereof, and an inserting end is provided on the inner end of the pivot; when the movable rod is at the first position, the inserting end is inserted into the slot.

8. The landing gear according to claim 1, wherein a shaft sleeve is fixed on the outer leg and the movable rod passes through the shaft sleeve.

9. The landing gear according to claim 8, wherein a clamping component is also provided between the shaft sleeve and the movable rod, which is used to clamp the movable rod at the first position or the second position.

10. The landing gear according to claim 9, wherein the clamping component comprises a steel ball and a spring; a mounting groove is provided on the movable rod along its radial direction, the spring is located in the mounting groove, and the steel ball is located at the outer end of the spring; the spring is used for pushing the steel ball outward; the inner wall of the sleeve is provided with two annular grooves; when the movable rod is at the first position, the steel ball is embedded in one of the annular grooves, and when the movable rod is at the second position, the steel ball is embedded in the other annular groove.