Electric extension ladder

Abstract

The invention relates to the technical field of extension ladders and particularly discloses an electric extension ladder which is characterized in that extension ladder units are sequentially nested in the length direction of the electric extension ladder, and the sizes of the extension ladder units are gradually changed; the extension ladder unit at the bottommost part is connected with the fixed ladder unit; stepping motors are arranged in the two ladder legs, screw rods extending into the extension ladder units are arranged at the power output ends of the stepping motors, threaded sleeves in threaded connection with the screw rods are arranged in the extension ladder units, the threaded sleeves are rotationally connected with the extension ladder units, and the two stepping motors operate synchronously. By adopting the elliptical aluminum pipe structure and the screw transmission mechanism, the problems of non-uniform torque and insufficient bending strength of the pipe wall of the traditional extension ladder are effectively improved, and the stability and durability of the extension ladder are improved. The device is driven by double motors, and closed-loop stepping motors are arranged on the left side and the right side respectively. The cooperative operation of the two motors ensures that the ladder is stably and quickly opened and closed, and the operation efficiency and the user experience are improved.

Description

Technical Field

[0001] The invention relates to the technical field of telescopic ladders, in particular to an electric telescopic ladder. Background Art

[0002] For a long time, traditional telescopic ladders have been opened manually, and the tubes are mostly round with manual adjustment mechanisms. This design results in uneven torque when unfolding, requiring more effort during operation and making it difficult to ensure smooth unfolding. At the same time, the wall of the round tube has insufficient bending strength, and is prone to deformation when subjected to heavy weight or external force, affecting safety and life.

[0003] Therefore, an electric telescopic ladder becomes a problem that people need to solve urgently. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an electric telescopic ladder, which can realize rapid and smooth extension and retraction of the telescopic ladder through electric drive, utilize a self-locking mechanism to ensure the stability of each telescopic unit after extension, and provide additional support through a telescopic support mechanism, thereby solving the problems of inconvenient operation and poor stability of traditional telescopic ladders and improving the safety and efficiency of aerial operations.

[0005] In order to solve the above technical problems, the present invention provides a technical solution as follows: an electric telescopic ladder, comprising a fixed ladder and a plurality of telescopic ladder units; the telescopic ladder units are nested in sequence along the length direction of the electric telescopic ladder, and the sizes are gradually changed; the telescopic ladder unit at the bottom is connected to the fixed ladder unit;

[0006] The fixed ladder includes two ladder legs and a cross brace connecting the two ladder legs. Stepper motors are arranged inside the two ladder legs. The power output end of the stepper motor is provided with a screw extending into the telescopic ladder unit. Each telescopic ladder unit is provided with a threaded sleeve threadedly connected to the screw. The threaded sleeve is rotatably connected to the telescopic ladder unit, and the two stepper motors operate synchronously.

[0007] Furthermore, the telescopic ladder unit includes two telescopic ladder tubes and a pedal connecting the two. The pedal of the telescopic ladder unit at the bottom is provided with a first self-locking mechanism, and the remaining telescopic ladder units are provided with a second self-locking mechanism. The first self-locking mechanism and the second self-locking mechanism are inserted into the telescopic ladder tubes to fix the telescopic ladder units after the telescopic ladder is extended.

[0008] Furthermore, the first self-locking mechanism includes a manual handle, a pulling plate, a first fixed sleeve, a first spring and a first insertion rod; the first fixed sleeve is fixed inside the pedal, the first spring is arranged inside the first fixed sleeve and one end of the first spring is fixed to the rear wall of the first fixed sleeve, and the other end is connected to the middle part of the first insertion rod, the first insertion rod passes through the first fixed sleeve and one end of the first spring is connected to the pulling plate, and the other end is plugged into the telescopic ladder tube; the end of the pulling plate is connected to the manual handle, and a slide groove is provided at the bottom of the pedal, and the lower end of the manual handle extends from the slide groove to the outside of the pedal.

[0009] Furthermore, the second self-locking mechanism includes a second fixing sleeve, a second spring, a second plug rod and a reset pendulum block, the second fixing sleeve is fixed inside the pedal, the second spring is arranged inside the second fixing sleeve and one end of the second spring is connected to the end of the second fixing sleeve and the other end is connected to the end of the second plug rod, one end of the second plug rod extends to the inside of the second fixing sleeve to connect to the second spring, and the other end is plugged into the telescopic ladder tube, the middle part of the reset pendulum block is rotatably connected to the side wall of the pedal, the two sides of the upper part of the reset pendulum block are separated on both sides of the second plug rod, the bottom of the reset pendulum block is provided with a limit groove, and the top of the pedal is provided with a limit protrusion matching the limit groove.

[0010] Furthermore, a fixing claw is provided on the top of the telescopic ladder unit at the top.

[0011] Furthermore, a telescopic support mechanism is provided at the bottom of the fixed ladder, and the telescopic support mechanism includes a main sleeve, a telescopic support tube, support legs, and a telescopic spring; the main sleeve is connected to two ladder legs, the telescopic support tube is symmetrically arranged on both sides of the main sleeve and is slidably connected thereto, the support legs are arranged at the ends of the telescopic support tube, and the ends of the main sleeve are provided with a limit lock connected to the telescopic support tube, and the telescopic spring is arranged inside the main sleeve and its two ends are respectively connected to the inner walls of the two telescopic support tubes.

[0012] Furthermore, the limit lock includes a lock seat, a return spring, and a press lock plate. The lock seat is fixed at the end of the main sleeve, and the press lock plate is rotatably connected to the lock seat on both sides. One end of the return spring is connected to the lock seat and the other end is connected to the press lock plate. A first lock hole is provided on the main sleeve, and a second lock hole is provided on the telescopic support tube. After the telescopic support tube is extended, the first lock hole corresponds to the second lock hole, and the press lock plate passes through the first lock hole and extends to the second lock hole to hook and lock it.

[0013] Furthermore, a slide is provided inside the ladder leg, a limiting convex plate is provided inside the slide, and a limiting tooth cooperating with the limiting convex plate is provided on the outer wall of the end of the telescopic support tube.

[0014] Furthermore, an anti-skid pad rotatably connected to the bottom of the support leg is provided.

[0015] Furthermore, the cross-sections of the ladder legs and the telescopic ladder tubes are both elliptical.

[0016] The advantages of the present invention over the prior art are as follows: the present invention adopts an elliptical aluminum tube structure and a screw transmission mechanism, which effectively improves the problems of uneven torque and insufficient bending strength of the tube wall of the traditional telescopic ladder, and improves the stability and durability of the telescopic ladder.

[0017] The present invention is driven by dual motors, with closed-loop stepper motors on both sides. The coordinated operation of the two motors ensures that the ladder can be opened and closed smoothly and quickly, improving operating efficiency and user experience.

[0018] The present invention provides a first self-locking mechanism at the bottom telescopic ladder unit, and a second self-locking mechanism at the remaining units. The first self-locking mechanism uses a manual pull handle to control the insertion of the plug rod, which is convenient for initial unlocking; the second self-locking mechanism uses the cooperation of the reset pendulum block with the limit groove and the limit convex block to achieve automatic locking and reset unlocking during the telescopic process, thereby improving the operating efficiency.

[0019] A telescopic support mechanism consisting of a main sleeve, a telescopic support tube, support legs and a telescopic spring is arranged at the bottom of the fixed ladder of the present invention, which cooperates with a limit lock to realize rapid deployment and locking, thereby enhancing the stability of the ladder when in use and adapting to different ground environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The utility model is a structural schematic diagram of an electric telescopic ladder of the present invention.

[0021] Figure 2 It is a front view of an electric telescopic ladder of the present invention.

[0022] Figure 3 The utility model is a side view of an electric telescopic ladder of the present invention.

[0023] Figure 4 It is a reference diagram of the use status of an electric telescopic ladder of the present invention.

[0024] Figure 5 It is a cross-sectional view of the ladder legs and telescopic ladder tubes.

[0025] Figure 6 It is a structural schematic diagram of the telescopic support mechanism.

[0026] Figure 7 It is the front view of the telescopic support mechanism.

[0027] Figure 8 It is a cross-sectional view of the telescopic support mechanism.

[0028] Fig. 9 yes Figure 8 A magnified view of the structure in the middle.

[0029] Fig.10 This is a schematic diagram of the structure of the first self-locking mechanism and the second self-locking mechanism. Figure 1 .

[0030] Fig.11 Structural schematic diagram of the first self-locking mechanism and the second self-locking mechanism Figure 2 .

[0031] Fig.12 It is a front view of the first self-locking mechanism and the second self-locking mechanism.

[0032] Fig.13 It is a cross-sectional view of the first self-locking mechanism and the second self-locking mechanism.

[0033] As shown in the figure: 1. Fixed ladder, 2. Telescopic ladder unit, 3. Ladder legs, 4. Cross brace, 5. Stepper motor, 6. Screw, 7. Threaded sleeve, 8. Telescopic ladder tube, 9. Pedal, 10. First self-locking mechanism, 11. Second self-locking mechanism, 12. Manual handle, 13. Pull plate, 14. First fixed sleeve, 15. First spring, 16. First plug rod, 17. Slide slot, 18. Second fixed sleeve, 19. Second spring, 2 0. Second plug rod, 21. Reset pendulum block, 22. Limiting groove, 23. Limiting protrusion, 24. Fixing claw, 25. Main sleeve, 26. Telescopic support tube, 27. Support leg, 28. Telescopic spring, 29. Limiting lock, 30. Lock seat, 31. Reset spring, 32. Press lock plate, 33. First locking hole, 34. Second locking hole, 35. Slide, 36. Limiting protrusion, 37. Limiting tooth, 38. Anti-slip pad. DETAILED DESCRIPTION

[0034] In the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “inside”, “outside”, “vertical” and “circumferential” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In the description of the present invention, "first feature" and "second feature" may include one or more of the features. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] The electric telescopic ladder of the present invention is further described in detail below with reference to the accompanying drawings.

[0038] Combined with Figure 1-13 The specific implementation process of the electric telescopic ladder of the present invention is as follows:

[0039] An electric telescopic ladder mainly consists of a fixed ladder 1, a plurality of telescopic ladder units 2 and a telescopic support mechanism. The fixed ladder 1 includes two ladder legs 3 and a cross brace 4 connecting the two; the telescopic ladder units 2 are nested in sequence along the length direction of the ladder, with gradually changing sizes, and the bottom telescopic ladder unit 2 is connected to the fixed ladder 1.

[0040] A stepper motor 5 is installed inside each of the two ladder legs 3 , and a screw rod 6 extending into the telescopic ladder unit 2 is provided at a power output end of the motor.

[0041] A threaded sleeve 7 is provided in each telescopic ladder unit 2 and is threadedly connected to the screw rod 6. The threaded sleeve 7 is rotatably connected to the telescopic ladder unit 2. When the stepper motor 5 is running, the screw rod 6 rotates to drive the threaded sleeve 7 to move along the screw rod 6, thereby driving the telescopic ladder unit 2 to extend and retract. The two stepper motors 5 run synchronously to ensure the smooth and synchronous movement of the telescopic ladder unit 2.

[0042] The first self-locking mechanism 10 is located in the pedal 9 of the bottom telescopic ladder unit 2, and includes a manual handle 12, a pulling plate 13, a first fixed sleeve 14, a first spring 15 and a first plug rod 16. The first fixed sleeve 14 is fixed inside the pedal 9, one end of the first spring 15 is fixed to the rear wall of the first fixed sleeve 14, and the other end is connected to the middle of the first plug rod 16. The first plug rod 16 passes through the first fixed sleeve 14, one end is connected to the pulling plate 13, and the other end is plugged into the telescopic ladder tube 8. The end of the pulling plate 13 is connected to the manual handle 12, and a slide groove 17 is provided at the bottom of the pedal 9. The lower end of the manual handle 12 extends from the slide groove 17 to the outside of the pedal 9. When unlocking is required, the handle is manually pulled to drive the first plug rod 16 to be pulled out of the telescopic ladder tube 8 through the pulling plate 13.

[0043] The second self-locking mechanism 11 is located in the remaining telescopic ladder units 2, and includes a second fixing sleeve 18, a second spring 19, a second plug rod 20 and a reset pendulum block 21. The second fixing sleeve 18 is fixed inside the pedal 9, one end of the second spring 19 is connected to the end of the second fixing sleeve 18, and the other end is connected to the end of the second plug rod 20. One end of the second plug rod 20 extends to the inside of the second fixing sleeve 18 to connect the second spring 19, and the other end is plugged into the telescopic ladder tube 8. The middle part of the reset pendulum block 21 is rotatably connected to the side wall of the pedal 9, and the two sides of the upper part are separated on both sides of the second plug rod 20. A limiting groove 22 is provided at the bottom, and a limiting protrusion 23 matching the limiting groove 22 is provided on the top of the pedal 9. When the telescopic ladder unit 2 is extended, the reset pendulum block 21 swings under the action of gravity or a spring, so that the second insertion rod 20 is inserted into the telescopic ladder tube 8 to achieve locking; when unlocking is required, the reset pendulum block 21 is swung by an external force, and the limiting groove 22 cooperates with the limiting protrusion 23 to keep the reset pendulum block 21 in the unlocked position, and the second insertion rod 20 is pulled out of the telescopic ladder tube 8 under the action of the spring.

[0044] A main sleeve 25 is provided at the bottom of the fixed ladder 1 , and the main sleeve 25 connects the two ladder legs 3 .

[0045] The telescopic support tubes 26 are symmetrically arranged on both sides of the main sleeve 25 and are slidably connected thereto, and the support legs 27 are arranged at the ends of the telescopic support tubes 26 .

[0046] The end of the main sleeve 25 is provided with a limit lock 29 connected to the telescopic support tube 26, and the limit lock 29 includes a lock seat 30, a return spring 31 and a press lock plate 32. The lock seat 30 is fixed to the end of the main sleeve 25, and the two sides of the press lock plate 32 are rotatably connected to the lock seat 30. One end of the return spring 31 is connected to the lock seat 30, and the other end is connected to the press lock plate 32. A first lock hole 33 is provided on the main sleeve 25, and a second lock hole 34 is provided on the telescopic support tube 26. When the telescopic support tube 26 is extended, the first lock hole 33 corresponds to the second lock hole 34, and the press lock plate 32 passes through the first lock hole 33 and extends to the second lock hole 34 to hook and lock it. When it is necessary to unlock the telescopic support tube 26 so that the telescopic support tube 26 can be retracted into the main sleeve 25, the press lock plate 32 can be pressed.

[0047] The telescopic spring 28 is disposed inside the main sleeve 25 and has two ends connected to the inner walls of the two telescopic support tubes 26 , respectively, to provide elastic force for the telescopic support tubes 26 to stretch outward.

[0048] A slideway 35 is provided inside the ladder leg 3, a limiting convex plate 36 is provided inside the slideway 35, and a limiting latch 37 cooperating with the limiting convex plate 36 is provided on the outer wall of the end of the telescopic support tube 26 to prevent the telescopic support tube 26 from over-extending.

[0049] The bottom of the support leg 27 is provided with an anti-skid pad 38 rotatably connected thereto, so as to increase the contact area with the ground and improve stability.

[0050] The top of the telescopic ladder unit 2 is provided with a fixing claw 24, which is convenient for fixing the ladder to a building or other support, and increases the safety of use. The cross-sections of the ladder legs 3 and the telescopic ladder tube 8 are both elliptical, which improves the structural strength and stability.

[0051] The raw materials of each component used in the present invention are mainly oval aluminum and plastic parts. The aluminum material is 60 series material profile, and the surface is anodized to ensure that it will not rust or oxidize for many years, and the safety performance is extremely high.

[0052] In terms of driving, the present invention innovatively adopts a dual-motor driving module. A closed-loop stepper motor 5 is provided on each side, and the two motors operate synchronously. During the opening and closing process, the two motors are like a tacit partner, driving at the same speed and force, and combined with the elliptical aluminum tube structure and the screw 6 transmission mechanism, the ladder can be opened and closed smoothly and quickly, avoiding problems such as jamming and tilting caused by inconsistent movements on both sides.

[0053] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. An electric telescopic ladder, characterized in that: It comprises a fixed ladder (1) and a plurality of telescopic ladder units (2); the telescopic ladder units (2) are nested in sequence along the length direction of the electric telescopic ladder and have gradually changing sizes; the telescopic ladder unit (2) at the bottom is connected to the fixed ladder (1) unit; The fixed ladder (1) comprises two ladder legs (3) and a cross brace (4) connecting the two ladder legs (3). A stepper motor (5) is arranged inside the two ladder legs (3). A power output end of the stepper motor (5) is provided with a screw rod (6) extending into the telescopic ladder unit (2). A threaded sleeve (7) threadedly connected to the screw rod (6) is arranged in each telescopic ladder unit (2). The threaded sleeve (7) is rotatably connected to the telescopic ladder unit (2). The two stepper motors (5) operate synchronously.

2. The electric telescopic ladder according to claim 1, characterized in that: The telescopic ladder unit (2) comprises two telescopic ladder tubes (8) and a pedal (9) connecting the two, a first self-locking mechanism (10) is arranged in the pedal (9) of the telescopic ladder unit (2) at the bottom, and a second self-locking mechanism (11) is arranged in the remaining telescopic ladder units (2), and the first self-locking mechanism (10) and the second self-locking mechanism (11) are inserted into the telescopic ladder tube (8) to fix the telescopic ladder unit (2) after the telescopic ladder is extended.

3. The electric telescopic ladder according to claim 2, characterized in that: The first self-locking mechanism (10) comprises a manual pull handle (12), a pulling plate (13), a first fixing sleeve (14), a first spring (15) and a first insertion rod (16); the first fixing sleeve (14) is fixed inside the pedal (9); the first spring (15) is arranged inside the first fixing sleeve (14) and one end of the first spring is fixed to the rear wall of the first fixing sleeve (14) and the other end is connected to the middle of the first insertion rod (16); the first insertion rod (16) passes through the first fixing sleeve (14) and one end of the first spring is connected to the pulling plate (13) and the other end is plugged into the telescopic ladder tube (8); the end of the pulling plate (13) is connected to the manual pull handle (12); a slide groove (17) is provided at the bottom of the pedal (9); the lower end of the manual pull handle (12) extends from the slide groove (17) to the outside of the pedal (9).

4. The electric telescopic ladder according to claim 3, characterized in that: The second self-locking mechanism (11) comprises a second fixing sleeve (18), a second spring (19), a second plug rod (20) and a reset pendulum block (21). The second fixing sleeve (18) is fixed inside the pedal (9). The second spring (19) is arranged inside the second fixing sleeve (18) and one end of the second spring is connected to the end of the second fixing sleeve (18) and the other end is connected to the end of the second plug rod (20). One end of the second plug rod (20) extends into the second fixing sleeve (18) and is connected to the second spring, while the other end is plugged into the telescopic ladder tube (8). The middle part of the reset pendulum block (21) is rotatably connected to the side wall of the pedal (9). The upper two sides of the reset pendulum block (21) are separated on both sides of the second plug rod (20). A limiting groove (22) is provided at the bottom of the reset pendulum block (21), and a limiting protrusion (23) matching the limiting groove (22) is provided at the top of the pedal (9).

5. The electric telescopic ladder according to claim 4, characterized in that: A fixing claw (24) is provided on the top of the telescopic ladder unit (2) at the top.

6. An electric telescopic ladder according to any one of claims 1 to 5, characterized in that: A telescopic support mechanism is provided at the bottom of the fixed ladder (1), and the telescopic support mechanism comprises a main sleeve (25), a telescopic support tube (26), a support leg (27), and a telescopic spring (28); the main sleeve (25) is connected to two ladder legs (3), the telescopic support tube (26) is symmetrically arranged on both sides of the main sleeve (25) and is slidably connected thereto, the support leg (27) is arranged at the end of the telescopic support tube (26), the end of the main sleeve (25) is provided with a limit lock (29) connected to the telescopic support tube (26), and the telescopic spring (28) is arranged inside the main sleeve (25) and its two ends are respectively connected to the inner walls of the two telescopic support tubes (26).

7. The electric telescopic ladder according to claim 6, characterized in that: The limit lock (29) comprises a lock seat (30), a return spring (31), and a pressing lock plate (32); the lock seat (30) is fixed at the end of the main sleeve (25); the pressing lock plate (32) is rotatably connected to the lock seat (30) at both sides; one end of the return spring (31) is connected to the lock seat (30) and the other end is connected to the pressing lock plate (32); a first locking hole (33) is provided on the main sleeve (25); a second locking hole (34) is provided on the telescopic support tube (26); after the telescopic support tube (26) is extended, the first locking hole (33) corresponds to the second locking hole (34) in position; the pressing lock plate (32) passes through the first locking hole (33) and extends to the second locking hole (34) to hook and lock it.

8. The electric telescopic ladder according to claim 7, characterized in that: A slideway (35) is provided inside the ladder leg (3), a limiting convex plate (36) is provided inside the slideway (35), and a limiting latch tooth (37) cooperating with the limiting convex plate (36) is provided on the outer wall of the end of the telescopic support tube (26).

9. The electric telescopic ladder according to claim 8, characterized in that: An anti-skid pad (38) rotatably connected to the bottom of the support leg (27) is provided.

10. The electric telescopic ladder according to claim 2, characterized in that: The cross sections of the ladder legs (3) and the telescopic ladder tube (8) are both elliptical.

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