CA3088952C - Ladder - Google Patents

Abstract

Embodiments of the present disclosure embodiment may disclose a ladder. The ladder may include a front ladder and a rear ladder. A top of the front ladder and a top of the rear ladder may be rotatably connected to adjust an angle between the front ladder and the rear ladder. At least one pole assembly may be arranged at the front ladder and/or the rear ladder. The at least one pole assembly may be extended in at least one direction to adjust a size of the ladder and/or a structure of the ladder. Additionally or alternatively, at least one socket may be arranged at the front ladder and/or the rear ladder. The at least one socket may be configured to receive an accessory plate assembly at least for holding goods.

Description

LADDER
TECHNICAL FIELD
[0001] The present disclosure relates to a technical field of a ladder, specifically relates to a ladder.
BACKGROUND

[0002] Ladders, as common goods, are tools used for climbing high. The structures and types of ladders are various, such as a trestle ladder, a manhole ladder, etc.

[0003] Considering actual conditions of using the ladder, a user may need to change tools on the ladder during operation and the conditions of a work site on which the ladder is used are restraint during the operation. The present disclosure provides a ladder with improved convenience and safety.
SUMMARY

[0004] One embodiments of the present disclosure may provide a ladder.
The ladder may include a front ladder and a rear ladder. A top of the front ladder and a top of the rear ladder may be rotatably connected to adjust an angle between the front ladder and the rear ladder. At least one pole assembly may be arranged at the front ladder and/or the rear ladder. The at least one pole assembly may be extended in at least one direction to adjust a size of the ladder and/or a structure of the ladder. Additionally or alternatively, at least one socket may be arranged at the front ladder and/or the rear ladder. The at least one socket may be configured to receive an accessory plate assembly at least for holding goods.

[0005] In some embodiments, the socket may be arranged at the top of the front ladder and/or the top of the rear ladder and rotatable on the front ladder Date Recue/Date Received 2020-06-17 and/or the rear ladder to adjust an installation angle of the accessory plate assembly.

[0006] In some embodiments, the socket may include an inner housing configured to receive the accessory plate assembly and an outer housing installed on the front ladder and/or rear ladder. The inner housing may be rotatable on the outer housing and locked with the outer housing when the inner housing is rotated to a preset angle.

[0007] In some embodiments, between the outer housing and the inner housing there may be a rotatable connection point and at least one detachable connection point. The rotatable connection point may be configured as a center of rotation when the inner housing is rotated on the outer housing. The at least one detachable connection point may be configured as at least one locking point between the inner housing and the outer housing when the inner housing is rotated to the preset angle.

[0008] In some embodiments, the at least one rotatable connection point may use a pin shaft, a spindle, a rivet or a screw to allow a rotatable connection between the inner housing and the outer housing.

[0009] In some embodiments, the at least one detachable connection point may use a pin shaft, a screw or a buckle to allow a locking between the inner housing and the outer housing.

[0010] In some embodiments, the outer housing may include a first buckle and a second buckle. The inner housing may include a first shackle buckled with the first buckle. The inner housing may include a second shackle buckled with the second buckle.

[0011] In some embodiments, the accessory plate assembly may possess a collapsible structure. The accessory plate assembly may include a connection Date Recue/Date Received 2020-06-17 pipe for matching a hole on the inner housing. A locking handle may be disposed on the connection pipe to fasten the connection pipe and the socket.

[0012] In some embodiments, the locking handle may include a handle body rotatably connected to the connection pipe and a spring strip connected to the connection pipe. A free end of the spring strip may abut an end of the handle body. A pin may be disposed on another end of the handle body. The pin may match a locking hole on the inner housing or the outer housing.

[0013] In some embodiments, the pole assembly may include a pole. An installation direction of the pole on the front ladder and/or the rear ladder may be adjustable.

[0014] In some embodiments, the pole may include an upper arm and a lower arm. The upper arm and the lower arm may be retractably connected. A
connection sleeve assembly for connecting with the front ladder and/or the rear ladder may be connected to the lower arm.

[0015] In some embodiments, the connection sleeve assembly may include two sliding frames, a fixed block, a handle cap, and a locking assembly. The fixed block and the handle cap may be disposed between the two sliding frames, and together with the two sliding frames, may form a circle encasing the lower arm. The locking assembly may successively pass through the handle cap, the lower arm, and the fixed block to be connected to a sliding block disposed on the ladder.

[0016] In some embodiments, the sliding block may be disposed on the front ladder and/or the rear ladder in at least two directions.

[0017] In some embodiments, the sliding block may be disposed along a length direction of the front ladder and/or the rear ladder or along a direction parallel to a pedal of the ladder.

Date Recue/Date Received 2020-06-17

[0018] In some embodiments, an end of the upper arm may be connected to a supporting foot in an adjustable angle.

[0019] In some embodiments, the upper arm may be connected to the supporting foot via a connection assembly. The connection assembly may include a connection block and a spring strip, a free end of which may have a pin lock. The connection block, the upper arm, and the supporting foot may all have at least two locking holes. One of the locking holes of the connection block, the upper arm, and the supporting foot may be configured to connect both the supporting foot and the connection block to the upper arm. The supporting foot may be rotatable on the connection block. At least one of the remaining locking holes on the connection block, the upper arm, and the supporting foot may be detachably connected to the supporting foot, the connection block, and the upper arm via the pin on the spring strip of the connection assembly.

[0020] In some embodiments, the spring strip of the connection assembly may include a U-shaped spring strip, and each of two free ends of the U-shaped spring strip may have the pin.
BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 'I is a schematic diagram illustrating an exemplary structure of a ladder extending as a trestle ladder according to an embodiment of the present disclosure;

[0022] FIG. 2 is a schematic diagram illustrating a ladder in a folding position according to an embodiment of the present disclosure;

[0023] FIG. 3 is a schematic diagram illustrating a ladder extending as a manhole ladder according to an embodiment of the present disclosure;

[0024] FIG. 4 is a schematic diagram illustrating an exploded view of a hinge locking mechanism of a ladder according to an embodiment of the present disclosure;

Date Recue/Date Received 2020-06-17

[0025] FIG. 5 is a schematic diagram illustrating a structure of an leg adjustment assembly of a ladder extending outside an outer ladder according to an embodiment of the present disclosure;

[0026] FIG. 6 is a schematic structural diagram illustrating a structure of an leg adjustment assembly of a ladder according to an embodiment of the present disclosure;

[0027] FIG. 7 is a schematic diagram illustrating an exploded view of an leg adjustment assembly according to an embodiment of the present disclosure;

[0028] FIG. 8 is a schematic diagram illustrating a connection between an leg adjustment assembly and an outer ladder according to an embodiment of the present disclosure;

[0029] FIG. 9 is a schematic diagram illustrating an enlarged view of part A in FIG. 8 according to an embodiment of the present disclosure;

[0030] FIG. 10 is a schematic diagram illustrating an enlarged view of part B
in FIG. 8 according to an embodiment of the present disclosure;

[0031] FIG. 11 is a schematic diagram illustrating an assembled shackle assembly in FIG. 10 according to an embodiment of the present disclosure;

[0032] FIG. 12 is a schematic diagram illustrating a state that a ladder is plugged into an accessory plate assembly via a socket according to an embodiment of the present disclosure;

[0033] FIG. 13 is a schematic diagram illustrating another state that a ladder is plugged into an accessory plate assembly via a socket according to an embodiment of the present disclosure;

[0034] FIG. 14 is a schematic diagram illustrating a state that an accessory plate assembly of a ladder is locked into a socket 300 according to an embodiment of the present disclosure;
Date Recue/Date Received 2020-06-17

[0035] FIG. 15 is a schematic diagram illustrating a structure of an accessory plate assembly according to an embodiment of the present disclosure;

[0036] FIG. 16 is a schematic diagram illustrating a structure of a socket according to an embodiment of the present disclosure;

[0037] FIG. 17 is a schematic diagram illustrating another view of a socket;

[0038] FIG. 18 is a schematic diagram illustrating a cross-sectional view along a C-C direction in FIG. 17;

[0039] FIG. 19 is schematic diagram illustrating an enlarged view of part D in FIG. 18;

[0040] FIG. 20 is a schematic diagram illustrating a state that a pole assembly is extended outside a ladder;

[0041] FIG. 21 is a schematic diagram illustrating a structure of a pole assembly according to an embodiment of the present disclosure;

[0042] FIG. 22 is schematic diagram illustrating an enlarged view of part E in FIG. 21 according to an embodiment of the present disclosure;

[0043] FIG. 23 is a schematic diagram illustrating a structure of a sliding block on a ladder;

[0044] FIG. 24 is a schematic diagram illustrating a structure of a locking assembly according to an embodiment of the present disclosure;

[0045] FIG. 25 is a schematic diagram illustrating a structure of a lower arm of a pole and a connection sleeve assembly of another embodiment in the present disclosure;

[0046] FIG. 26 is a schematic diagram illustrating a connection of a lower arm of a pole and a connection sleeve assembly in another state;

[0047] FIG. 27 is a schematic diagram illustrating a state of a pole assembly and a ladder when the connection between the lower arm and the connection sleeve assembly is in the another state as shown in FIG. 26;

Date Recue/Date Received 2020-06-17

[0048] FIG. 28 is a schematic diagram illustrating another state of a pole assembly and a ladder when the connection between the lower arm and the connection sleeve assembly is in the another state as shown in FIG. 26; and

[0049] FIG. 29 is a schematic diagram illustrating a structure of a fixed bracket in the connection sleeve assembly in FIG. 25.

[0050] In the figures, 001 is a front ladder and 002 is a rear ladder.

[0051] 100 is an inner ladder, 101 is a half-hinge, 102 is a pin hole, 103 is a locking hole, 104 is a pin seat, 105 is a sliding shaft, 106 is a pin, 107 is a spring, 108 is a pulley, 109 is a button cover, 110 is a circlip, and 111 is a gasket.

[0052] 200 is an outer ladder, 201 is an adjustment leg, 202 is a protective cover, 203 is a foot pedal, 204 is an elastic member, 205 is a spacing buffer block, 206 is a buckle, 207 is a housing, 208 is an end cover, 209 is a spring strip, and 210 is a shackle.

[0053] 300 is a socket, 301 is an outer housing, 302 is an inner housing, is a first buckle, 304 is a second buckle, 305 is a first shackle, 306 is a second shackle, 307 is a movable plug, 308 is an elastic member, 309 is a curved surface, 310 is an buckling surface, 311 is an inclined surface, 312 is a transition surface, and 313 is a bonding surface.

[0054] 400 is a pole assembly, 410 is a supporting foot, 420 is a connection assembly, 421 is a connection block, 422 is a spring strip, 423 is a pin, 430 is a pole, 431 is an upper arm, 432 is a lower arm, 433 is a locking handle, 440 is a connection sleeve assembly, 441 is a sliding frame, 442 is a fixed block, 443 is a handle cap, 444 is a locking assembly, 445 is a card slot, 446 is a lock tongue, 447 is a protrusion; 448 is a installation block, 449 is a mounting seat, 450 is a mounting plate, 451 is a guiding plate, 452 is a connection rod, 4521 is a connecting section, 4522 is a guiding section, 453 is a friction ring, 454 is a guiding hole, 455 is a return spring, 456 is a bottom plate, 457 is a supporting Date Recue/Date Received 2020-06-17 plate, 458 is a clamping piece, 459 is a rotating end cover, 460 is a supporting sleeve, 461 is a strip groove, 462 is a positioning hole, 463 is an outer pin, 464 is an inner pin, and 465 is a compression spring.

[0055] 500 is an leg adjustment assembly.

[0056] 600 is a roller.

[0057] 700 is an accessory plate assembly, 701 is a connection pipe, 702 is an accessory plate, 703 is a moveable shackle, 704 is a hinge point, 705 is a connection rod, 706 is a spring strip, 707 is a handle body, 708 is a pin, and is a hanger.

[0058] 800 is a rung.

[0059] 900 is a sliding block.
DETAILED DESCRIPTION

[0060] In order to make the purposes, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present disclosure and not intended to limit the present disclosure.

[0061] Instead, the present disclosure covers any alternatives, modifications, and equivalents to the essences and the scope of the present disclosure defined by the claims. Further, in order to provide the public with a better understanding of the present disclosure, some specific details are described in detail in the detailed description of the present disclosure below. Those skilled in the art can fully understand the present disclosure without the descriptions of these details.

[0062] One embodiment of the present disclosure may provide a ladder. The ladder may include a front ladder 001 and a rear ladder 002. The top of the front ladder 001 and the top of the rear ladder 002 may be rotatably connected to Date Recue/Date Received 2020-06-17 adjust an angle between the front ladder 001 and the rear ladder 002. The front ladder 001 and/or the rear ladder 002 may have a pole assembly 400. The pole assembly 400 may be extended outside the front ladder 001 and/or the rear ladder 002 in different directions. The front ladder 001 and/or the rear ladder 002 may have a socket 300 for receiving an accessory plate assembly which is at least for holding goods.

[0063] Some embodiments may provide a ladder. The ladder may include a front ladder 001 and a rear ladder 002. The top of the front ladder 001 and the top of the rear ladder 002 may be rotatably connected to adjust an angle between the front ladder 001 and the rear ladder 002. The front ladder 001 and/or the rear ladder 002 may have a pole assembly 400. The pole assembly 400 may be extended outside the front ladder 001 and/or the rear ladder 002 in different directions.

[0064] Some embodiments may provide a ladder. The ladder may include a front ladder 001 and a rear ladder 002. The top of the front ladder 001 and the top of the rear ladder 002 may be rotatably connected to adjust an angle between the front ladder 001 and the rear ladder 002. The front ladder 001 and/or the rear ladder 002 may have a socket 300 for receiving an accessory plate assembly which is at least for holding goods.

[0065] As referred to FIGs. 1-3, the top of the front ladder 001 and the top of the rear ladder 002 may be rotatably connected to adjust the angle between the front ladder 001 and the rear ladder 002. As shown in FIG. 1, the front ladder 001 and the rear ladder 002 may form a trestle ladder. FIG. 2 is a schematic diagram illustrating the front ladder 001 and the rear ladder 002 in a folding position. FIG. 3 is a schematic diagram illustrating the front ladder 001 and the rear ladder 002 forming a manhole ladder. The ladder in the present disclosure Date Recue/Date Received 2020-06-17 may be adjusted according to the needs of the operator, such that the ladder may be presented differently in usage and will not be described here.

[0066] In some embodiments, as referred to FIG. 1, both the front ladder and the rear ladder 002 may include an inner ladder 100 and an outer ladder 200, respectively. In some embodiments, both the inner ladder 100 and the outer ladder 200 may include columns. The columns may be connected by rungs 800 to form steps of the ladder.

[0067] In some embodiments, the outer ladder 200 may slide up and down along the inner ladder 100. In some embodiments, the outer ladder 200 may have sliding grooves. The inner ladder 100 may be disposed within the sliding groove to allow the sliding between the outer ladder 200 and the inner ladder 100. Therefore, a length of the outer ladder 200 extending outside the inner ladder 100 may be adjusted, thereby facilitating to adjust a length of the ladder to meet the needs of different heights and improving the convenience in usage.

[0068] In some embodiments, the outer ladder 200 and the inner ladder 100 may be fastened by a locking member (e.g., a pin, a bolt) to allow the locking between the outer ladder 200 and the inner ladder 100. In some embodiments, when the outer ladder 200 and the inner ladder 100 are locked together by the pin or the bolt, the inner ladder 100 may have a plurality of locking holes to lock the outer ladder 200 at different positions of the inner ladder 100. When the outer ladder and the inner ladder 100 are locked together, the rung 800 of the inner ladder 100 may correspond to the rung 800 of the outer ladder 200 in locations, such that the rungs of the inner ladder and the rungs of the outer ladder may form the steps of the ladder.

[0069] In some embodiments, when the outer ladder 200 and the inner ladder 100 are locked together, the upper surfaces of the rung 800 of the inner ladder 100 and the outer ladder 200 may be on the same horizontal plane. In some Date Recue/Date Received 2020-06-17 embodiments, when the outer ladder and the inner ladder are locked together, the upper surface of the rung 800 of the outer ladder 200 may be 1-10 millimeters higher than that of the rung 800 of the inner ladder 100 to form an inclined step, which may reduce the risk of the slipping and improve the safety of the operator using the ladder.

[0070] In some embodiments, the upper surface of the rung 800 may be applied with an anti-slip treatment, such as being covered with an anti-slip rubber layer, an anti-slip pattern, etc., to improve the safety of the ladder.

[0071] In some embodiments, the top of the front ladder 001 and the top of the rear ladder 002 may include a hinge locking mechanism configured to adjust the angle between the front ladder and the rear ladder. The hinge locking mechanism may lock the angle between the front ladder and the rear ladder. In some embodiments, the angle between the top of the inner ladder of the front ladder and the top of the inner ladder of the rear ladder may be adjusted and locked via the hinge locking mechanism.

[0072] As referred to FIG. 4, the hinge locking mechanism may include a half-hinge arranged at the top of the inner ladder 100 of the front ladder 001 and the top of the inner ladder 100 of the rear ladder 002, respectively. That is to say, the tops of the two inner ladders 100 may be hinged by the two half-hinges 101, and the two half-hinges may form the hinge between the inner ladders. Both of the half-hinges 101 may have a locking hole 103 and a pin hole 102. The pin holes 102 of the two half-hinges 101 may be matched with each other. The locations of locking holes 103 of the two half-hinges may match. The pin hole 102 and the locking hole 103 may each have an elastic pin. The elastic pin may include a pin seat 104. A middle part of the pin seat 104 may have a sliding shaft 105 matching the pin hole 102. The pin seat 104 may also have at least one pin 106 matching the locking hole 103. The sliding shaft 105 may be Date Recue/Date Received 2020-06-17 sleeved with a spring 107. Two ends of the spring 107 may have a circlip 110 and a gasket 111. An end of the sliding shaft 105 may be connected to a pulley 108 and a button cover 109 through the pin holes 102 of the two half-hinges 101.
In the usage process, the two half-hinges 101 may be hinged via the sliding shaft 105 and locked via the pin 106.

[0073] In some embodiments, in order to improve the locking stability, the pin seat 104 may have two pins 106. One of the half-hinges 101 may have two locking holes 103 corresponding to the pins 106. The two locking holes 103 may be formed as a set. The other half-hinge 101 may have at least two sets of the locking holes 103. One of the sets may be configured as reference locking holes, and the remaining sets of the at least two sets may be formed by rotating the reference locking holes at any angle of 0-90 along the center of the pin hole 102.

[0074] In the usage process of the hinge locking mechanism of the present disclosure, when the two pins 106 match a set of the locking holes 103 of the two half-hinges, the front ladder 001 and the rear ladder 002 may be at an angle.
When the angle between the front ladder and the rear ladder needs to be adjusted, the button cover 109 may be pressed, and then an ejector pin of the button cover 109 may press the sliding shaft 105, thereby moving the pin seat 104 and the pin 106 until the pin 106 is separated from the locking hole 103.
Then the angle between the front ladder 001 and the rear ladder 002 may be adjusted based on needs (e.g., an adjusted angle). Then the button cover 109 may be released. The pin seat 104 may drive the pin 106 to be engaged with another set of the locking holes 103 (a position of the another set of the locking holes 103 matching the adjusted angle between the front ladder and the rear ladder) by a reset force of the spring 107 to complete the adjustment and the locking of the angle between the front ladder 001 and the rear ladder 002.

Date Recue/Date Received 2020-06-17

[0075] The hinge locking mechanism of the present disclosure may unlock the front ladder and the rear ladder by directly pressing in usage. After the adjustment is completed, the pin 106 and the locking hole 103 may be automatically engaged via the spring 107 to implement the locking, such that the adjustment and the usage may be convenient.

[0076] As referred to FIG. 5, FIG. 5 is a schematic diagram illustrating a structure of an leg adjustment assembly 500 extending outside a ladder. By adjusting the length of the leg adjustment assembly extending outside the ladder, the length adjustment capability of the ladder may be improved, and thereby improving the usage convenience of the ladder. In some embodiments, the leg adjustment assembly 500 may be installed on the front ladder 001 and/or the rear ladder 002. Preferably, to improve the usage convenience of the ladder, the leg adjustment assembly 500 may be installed on both sides of the front ladder 001 and/or the rear ladder 002. In some embodiments, when the front ladder 001 and the rear ladder 002 may include the inner ladder 100 and the outer ladder 200, the leg adjustment assembly 500 may be installed on the outer ladder 200.

[0077] As referred to FIGs. 6-11, FIG. 6 is a schematic diagram illustrating a structure of an adjustment leg 201. FIG. 7 is a schematic diagram illustrating an exploded view of an adjustment leg. FIG. 8 is a schematic diagram illustrating a connection between the leg adjustment assembly 500 and the outer ladder.
FIG. 9 is a schematic diagram illustrating an enlarged view of part A in FIG.

and shows a schematic diagram of assembling an upper side of the adjustment leg 201 and the outer ladder 200. FIG. 10 is a schematic diagram illustrating an enlarged view of part B in FIG. 8 and shows an exploded view of a shackle assembly of the leg adjustment assembly 500. The shackle assembly may be configured to lock the adjustment leg 201 on the outer ladder and form a Date Recue/Date Received 2020-06-17 detachable connection with the outer ladder. FIG. 11 is a schematic diagram illustrating an assembled shackle assembly.

[0078] As referred to FIGs. 6-11, in some embodiments, the leg adjustment assembly 500 may include the adjustment leg 201. The lower side of the adjustment leg 201 may be connected with a protective cover 202. The adjustment leg 201 may be also connected with a foot pedal 203. The adjustment leg 201 may be internally connected with an elastic member 204.
The adjustment leg 201 may slide up and down in the outer ladder 200. The outer ladder 200 may also include a spacing buffer block 205. The spacing buffer block 205 may have a buckle 206. The lower side of the elastic member 204 may be connected to the adjustment leg 201. The upper side of the elastic member 204 may be connected with the buckle 206. The outer ladder 200 may have a shackle assembly for locking the adjustment leg with the outer ladder together.

[0079] The shackle assembly may include a housing 207, an end cap 208, a spring strip 209, and a shackle 210. The housing 207 and the end cap 208 may form a space for accommodating the spring strip and the shackle. An end of the spring strip 209 may extend outside the housing 207. The other end of the spring strip 209 may be connected to the shackle 210. The shackle 210 may include two locking grips. One of the locking grips may be connected to a fixed slot of the outer ladder, and the other locking grip may be passed through the outer ladder and match a locking hole of the adjustment leg.

[0080] In the process of using the leg adjustment assembly of the present disclosure, when the leg adjustment assembly 500 needs to be extended, the spring strip 209 may be pressed to separate a lock catch of the shackle 210 from a certain set of the locking holes of the adjustment leg 201. The foot pedal may be pressed to drive the adjustment leg 201 to move downward, thereby Date Recue/Date Received 2020-06-17 extending the adjustment leg 201 outside the outer ladder 200 for adjusting the height of the ladder. When the adjustment leg 201 moves to a suitable position, the elastic strip 209 may be released. The lock catch of the shackle 210 may match another set of the locking holes of the adjustment leg 201 for locking.
When the adjustment leg 201 needs to be retracted, the spring strip 209 may be pressed to separate the lock catch of the shackle 210 from the locking holes of the adjustment leg 201. The adjustment leg 201 may be retracted and reset automatically by the elastic member 204. The adjustment of the leg adjustment assembly of the present disclosure may be convenient.

[0081] In some embodiments, the adjustment leg 201 may also be connected with a roller 600 to move the ladder easily.

[0082] As referred to FIGs. 12-14, FIG. 12 is a schematic diagram illustrating a state of plugging the accessory plate assembly 700 into the socket 300. FIG.

13 is a schematic diagram illustrating another state of plugging the accessory plate assembly 700 into the socket 300. In FIGs. 12-13, the accessory plate assembly 700 may be not locked together with the socket 300. As shown in FIGs. 12-13, an installation angle of the accessory plate assembly may be adjusted to meet different needs using the socket. In the present disclosure, the accessory plate assembly may be set up using the socket. The accessory plate assembly may be configured for convenience, holding thing that an operator may use during operation. The operator may thus spend less time climbing up and down to getting the things. The operation efficiency of the operator may be improved. At the same time, the accessory plate assembly may also be configured as a handrail for the operator to climb up the top of the ladder.
When the operator works, the accessory plate assembly 700 may be configured as the handrail for the operator to improve the safety of using the ladder. FIG. 14 shows a structure that the accessory plate assembly 700 and the socket 300 are Date Recue/Date Received 2020-06-17 locked with each other when the accessory plate assembly 700 is in a folding state.

[0083] As referred to FIG. 15, FIG. 15 is a schematic diagram illustrating a structure of the accessory plate assembly 700 according to an embodiment of the present disclosure. A structure of the accessory plate assembly 700 may include a collapsible structure. The accessory plate assembly 700 may include a connection pipe 701 matching a hole of the socket 300. The connection pipe 701 may have a locking handle for fastening the connection pipe 701 and the socket 300.

[0084] In some embodiments, the locking handle may include a handle body 707 rotatably connected to the connection pipe 701 and a spring strip 706 connected to the connection pipe 701. One side of the spring strip 706 may be connected to the connection pipe 701, and the free end of the spring strip 706 may be abutted against the handle body 707. The other side of the handle body 707 may have a pin 708 for matching the locking hole (i.e., the locking hole on the inner housing or the outer housing) of the socket. That is, the inner housing 302 and/or the outer housing 301 of the socket 300 may have the locking hole configured to match the pin 708 to lock the accessory plate assembly 700. For example, the free end of the spring strip 706 may abut an inner side of one end of handle body 707. Under the force of the spring strip 706, the end of handle body 707 may be pushed away from the connection pipe 701. Between the handle body 707 and the connection pipe 701 there may be a rotatable connection point configured as a supporting point. The pin 708 set on the other end of handle body 707 may tightly cling to the connection pipe 701 under the force of the spring strip 706, thereby locking the pin 708 in the locking hole on the socket.

Date Recue/Date Received 2020-06-17

[0085] In some embodiments, the accessory plate assembly 700 may also include an accessory plate 702 connected to the connection pipe 701. A
movable shackle 703 may be installed on the connection pipe 701. A
connection rod 705 may be hinged on the movable shackle 703 on one end.
The other end of the connection rod 705 may be hinged on the accessory plate 702. The accessory plate 702 may also be hinged on the connection pipe 701 via a hinge point 704. When the accessory plate assembly 700 needs to be folded, the movable shackle 703 may be slid up and down along the connection pipe 701, pulling the connection rod 705 making the accessory plate 702 rotating around the hinge point 704 , thereby finishing unfolding or folding the accessory plate assembly.

[0086] In some embodiments, the accessory plate 702 may also have a hanger 709. When the accessory plate assembly 700 is folded, the accessory plate assembly 700 may be suspended on the rung 800 of the ladder via the hanger 709 to reduce the occupation of the space.

[0087] FIG. 16 is a schematic diagram illustrating a structure of a socket according to an embodiment. FIG. 17 is a schematic diagram illustrating a side view of the socket according to an embodiment. FIG. 18 is a schematic diagram illustrating a cross-sectional view along a C-C direction in FIG. 17. FIG. 19 is a schematic diagram illustrating an enlarged view of part D in FIG. 18. The socket 300 may be holded on the top of the front ladder and/or the top of the rear ladder and rotated on the front ladder and/or the rear ladder to adjust the installation angle of the accessory plate assembly. In some embodiments, the front ladder 001 and the rear ladder 002 may include the inner ladder 100 and the outer ladder 200. The socket 300 may be installed on the top of the inner ladder 100.
In the present disclosure, the socket 300 may be used for the installation of the accessory plate assembly 700 and adjust the installation angle of the accessory Date Recue/Date Received 2020-06-17 plate assembly 700, such that the operator may adjust the position of the accessory plate assembly 700 according to actual needs, thereby improving the convenience of the operator.

[0088] In some embodiments, in order to improve the stability of installing the accessory plate assembly 700, a count of the socket 300 on the front ladder may be 2, or a count of the socket 300 on the real ladder 002 may be 2, or a count of the socket on the front ladder and the rear ladder may be 2, respectively, such that the operator may more easily adjust the installed position of the accessory plate assembly 700 to improve the usage convenience.

[0089] As referred to FIGs. 16-19, in some embodiments, the socket 300 may include an inner housing for receiving the accessory plate assembly 700 and the outer housing 301 installed on the front ladder and/or the rear ladder. The inner housing may be rotated on the outer housing. The inner housing may be locked on the outer housing when the inner housing is rotated to a preset angle. In some embodiments, the inner housing may have a hole for receiving the connection pipe 701 of the accessory plate assembly 700 to facilitate the connection of the accessory plate assembly 700 and the socket. Preferably, the hole of the inner housing for receiving the connection pipe 701 may be a through hole, that is, the hole may run through the inner housing 302, such that the connection pipe 701 may be received from different directions, thereby improving the usage convenience.

[0090] In order to improve the stability of assembling the accessory plate assembly 700, the inner housing 302 and/or the outer housing 301 may have locking holes for engaging with the pin 708 on the handle body 707. A count of the locking holes may be at least two to facilitate the locking of the accessory plate assembly 700 at different angles.

Date Recue/Date Received 2020-06-17

[0091] In some embodiments, there may be at least two connection points between the inner housing 302 and the outer housing 301. One of the connection points may be configured as a center of rotation when the inner housing is rotated on the outer housing. The remaining connection point(s) may be configured as detachable connection point(s) for locking the inner housing on the outer housing. The center of rotation may include a pin shaft or a rivet, that is, an axis of the pin shaft and the rivet may be configured as a rotation axis when the inner housing is rotated on the outer housing. The detachable connection point(s) may include a bolt screw component, a pin shaft component, a buckle component, etc. The detachable connection point(s) between the outer housing 301 and the inner housing 302 may be any structure capable of the detachable connection.

[0092] In some embodiments, the inner housing 302 and the outer housing 301 may be rotatably connected via the pin shaft or the rivet. The axis of the pin shaft or the rivet may be configured as the axis of the rotation of the inner housing on the outer housing. When the inner housing 302 moves a certain angle on the outer housing 301, the inner housing and the outer housing may be buckled with each other. In some embodiments, the inner housing and the outer housing may be fixed via buckling, and the fastener needn't to be disassembled during use, which has the advantages of convenient usage.

[0093] As referred to FIGs. 16-19, in some embodiments, the outer housing 301 may have a first buckle 303 and a second buckle 305. The inner housing 302 may have a first shackle 305 buckled with the first buckle 303. The inner housing 302 may have a second shackle 306 buckled with the second buckle 304.

Date Recue/Date Received 2020-06-17

[0094] In some embodiments, the first buckle and the second buckle may be installed on the inner housing. The first shackle and the second shackle may be installed on the outer housing.

[0095] In some embodiments, the first buckle 303 may include a curved surface 309 and a buckling surface 310 that are connected to each other. The intersection of the curved surface 309 and the buckling surface 310 may be smoothly transitioned. The curved surface 309 and the buckling surface 310 may form a protrusion extending outside the outer housing 301. The first shackle 305 may include an inclined surface 311, a transition surface 312, and a bonding surface 313 that are sequentially connected to each other. The inclined surface 311 and the transition surface 312 may transit smoothly, and the transition surface 312 and the bonding surface 313 may transit smoothly. The transition surface and the bonding surface may form a stepped shape. When the first buckle 303 and the first shackle 305 are required to lock the inner housing and the outer housing, and the inner housing 302 is rotated on the outer housing 301, the inclined surface 311 may be firstly in contact with the curved surface 309, and then the transition surface 312 may be in contact with the curved surface 309. As the inner housing rotates, the press between the first buckle 303 and the first shackle 305 may be the largest when the transition surface moves to the end of the curved surface. At this time, the inner housing may continue to rotate, the transition surface 312 and the curved surface 309 may be separated from each other. The buckling surface 310 and the bonding surface 313 may be fitted with each other. At this time, the first shackle may have moved to an accommodation space formed between the first buckle and the outer housing. At the same time, one side of the inner housing may contact that of the outer housing r to complete the locking between the inner housing and the outer housing. The locking manner between the first buckle and the first Date Recue/Date Received 2020-06-17 shackle of the present disclosure may have the advantages of locking convenience, thereby locking the inner housing easily. When the first buckle and the first shackle need to be unlocked, the inner housing may be rotated to separate the step of the first shackle from the protrusion of the first buckle.

[0096] In some embodiments, the second buckle 304 may have a rounded protrusion. The second shackle 306 may include a pin shaft. The pin shaft may have a movable plug 307. The movable plug 307 may have a hole fitting with the pin shaft. The two ends of the pin shaft may be respectively buckled with each other via the hole of the movable plug 307. The movable plug 307 may have an elastic member 308. The movable plug 307 may be moved on the inner housing 301. During the rotation of the inner housing, when the inner housing and the outer housing need to be locked by the second buckle 304 and the second shackle 306, the second buckle may press the pin shaft. The pin shaft may then press the movable plug 307 to move along the inner housing until the protrusion of the second buckle passes over the pin shaft. At this time, the protrusion of the second buckle and the pin shaft may be locked. The movable plug 307 may be reset by the elastic member 308 to apply a preload to the pin shaft. Thus, the locking between the second buckle and the second shackle may be completed, and the locking may be convenient. When the second buckle and the second shackle need to be unlocked, the second buckle may press the pin shaft to separate the second buckle from the pin shaft. The pin shaft may be movable via the elastic member 308. The reset of the elastic member 308 may ensure the buckling between the pin shaft and the second buckle. At the same time, the friction between the second buckle and the second shackle may be reduced during the locking and unlocking process, and the service life of the second buckle may be improved.

Date Recue/Date Received 2020-06-17

[0097] As referred to FIGs. 1, 3, and 20, the front ladder and/or the rear ladder may have the pole assembly 400 that may extend outside the ladder from at least two directions. The pole assembly 400 may be folded in the side surface of the ladder in FIG. 1 and not occupy the space. In some embodiments, the front ladder and the rear ladder may be extended to an angle of 180 . At this time, the ladder may be shown as the manhole ladder in FIG.
3.
The pole assembly 400 may be disposed on the top of the ladder along a direction perpendicular to the length direction of the ladder or along the length direction of the ladder. At this time, the pole assembly 400 may be configured as an armrest when the operator climbs on the step of the top of the ladder to improve the safety of the operator. When the pole assembly 400 is disposed along the direction perpendicular to the length direction of the ladder, the pole assembly 400 may also be configured as a horizontal support for the ladder to increase a contact area between the ladder and a supporting surface (such as a wall) to improve the stability of the ladder. In some embodiments, the pole assembly 400 may also be disposed at the bottom of the manhole ladder along the direction perpendicular to the length direction of the ladder and configured as a horizontal supporting point for the ladder to improve the stability of the ladder.
When the ladder is used for different planes, the pole assembly 400 may tightly cling to the bottom of the ladder and configured as an extension component of the ladder to improve the convenience of the ladder in FIG. 20. It should be noted that FIGs. 1, 3 and 20 only show three states of the pole assembly 400 in three different directions, and the state of the pole assembly 400 may not be limited to the three states.

[0098] In an embodiment of the present disclosure, both sides of the front ladder 001 and/or the rear ladder 002 may have the pole assembly 400. When the front ladder 001 and the rear ladder 002 may include the inner ladder 100 Date Recue/Date Received 2020-06-17 and the outer ladder 200, the pole assembly 400 may be disposed on the outer ladder 200.
10099] As referred to FIG. 21, FIG. 21 is a schematic diagram illustrating a structure of a pole assembly according to an embodiment of the present disclosure. The pole assembly 400 may include a pole 430 and a connection sleeve assembly 440 for connecting the pole 430 to the front ladder 001 and/or the rear ladder 002. In some embodiments, a sliding block 900 may be disposed on the front ladder and/or the rear ladder in at least two different directions. The connection sleeve assembly 440 may be slidably coupled to the sliding block 900 and locked with the sliding block 900, such that the pole assembly 400 may extend outside the ladder in the different directions. For example, the sliding block may be installed along the direction of the length direction of the front ladder and/or the rear ladder (installed along a direction perpendicular to the direction of the rung 800). The sliding block may also be installed in a direction parallel to the rung 800. The sliding block may also be tilted to the front ladder and/or the rear ladder, such that the pole assembly may extend outside the ladder in the different directions. In the present disclosure, the pole assembly may be installed on the ladder in the means of the sliding block, such that the structure may be simple, and the usage may be convenient.
[0100] In some embodiments, the length of the pole may not be adjusted. In some embodiments, the pole 430 may be a telescopic pole whose length is adjustable. The pole 430 may include an upper arm and a lower arm. The connection between the upper arm and the lower arm may be retractable. In some embodiments, the upper arm and the lower arm may be connected together via a locking handle 433. The upper arm may have a plurality of locking holes. The lower arm may have a locking hole. When the length of the Date Recue/Date Received 2020-06-17 pole 430 is adjusted, the upper arm may be pulled out from the lower arm and match one of the plurality of locking holes in the upper arm with the locking hole on the lower arm. Then the pole 430 may be locked by the locking handle 433.
In some embodiments, the structure of the locking handle 433 may be similar to the description of the locking handle in the accessory plate assembly 700 and will not be described herein. The locking handle 433 may be installed on the upper arm 431 or installed on the lower arm 433 as long as positions between the upper arm and the lower arm may be adjusted and locked and it will not be described here.
[0101] In some embodiments, the length between the upper arm and the lower arm may also be adjusted by a manner of a threaded connection. In some embodiments, the upper arm and the lower arm may be slidably connected. The upper arm and the lower arm may be locked by a moveable buckle.
[0102] In some embodiments, the pole 430 may be connected to a supporting foot 410 via a connection assembly 420. An angle between the supporting foot and the pole 430 may be adjusted. By setting the supporting foot on the pole 430, the supporting foot may be configured as a support for the ground. The supporting foot may also be configured as a support for a wall and a roof (for example, when the ladder is placed on a glass or a window, the supporting foot may be configured as a contact connection between the ladder and the wall and the roof), thereby improving the usage convenience of the ladder. At the same time, in the present disclosure, the angle between the supporting foot 410 and the pole 430 may be adjusted to suit different scenarios, further improving the usage convenience of the ladder.
[0103] In some embodiments, the connection assembly 420 may include a connection block 421 and a spring strip 422. A free end of the spring strip Date Recue/Date Received 2020-06-17 may have a pin 423. Each of the connection block 421, the upper arm 431 and the supporting foot 410 may have at least two locking holes. One of the locking holes of the lock blocks 421, the upper arm 431 and the supporting foot 410 may be configured to connect the connection block 421, the upper arm 431 and the supporting foot 410 via a pin shaft, a rivet or a screw. The pin shaft, the rivet or the screw in the locking hole may be configured as a rotation axis of the supporting foot, the connection block and the upper arm. The remaining locking holes on the connection block 421, the upper arm 431 and the supporting foot 410 may be configured to be detachably connected to the connection block, the upper arm 431 and the supporting foot 410 by the pin lock 423 on the spring strip 422 to adjust the angle between the supporting foot and the upper arm 431. In some embodiments, the upper arm 431 and the connection block 421 may have two locking holes (a and b). The lock foot 410 may have three locking holes (a, band c). The locking hole a of the upper arm 431, the connection block 421, and the lock foot 410 may be plugged into the pin shaft. The pin shaft may connect the upper arm 431, the connection block 421 and the supporting foot 410 to each other. A center line of the pin shaft in the locking hole a may be used as the rotation axis of the supporting foot on the connection block 421 and the upper arm 431. Then the pin 423 on the spring strip 422 may be successively passed through the locking hole b of the upper arm 431, the locking hole b on the connection block 421, and the locking hole b on the supporting foot 410. At this time, the supporting foot 410 may be connected to the locking holes b of the connection block 421 and the upper arm 431 via the pin 423, thereby fastening the supporting foot 410. During a specified installation adjustment process, the connection block 421 may be sleeved on the periphery of the upper arm 431. The locking hole a and b on the connection block may correspond to the locking hole a and the locking hole b on the upper arm 431, respectively.
At Date Recue/Date Received 2020-06-17 the same time, the elastic strip 422 may be plugged into the upper arm 431 until the pin 423 on the elastic strip 422 corresponds to the locking holes b of the connection block and the upper arm. The pin 423 may successively pass through the locking hole b on the upper arm 431 and the locking hole b on the connection block 421 under the force of the spring strip, such that the pin may be exposed. At the same time, the supporting foot 410 may be sleeved on the periphery of the connection block 421 such that the locking hole a of the supporting foot 410 may match that of the connection block 421. The pin shaft, the locking hole may receive the rivet or the screw. The pin shaft, the rivet or the screw in the locking hole a may be configured as the rotation axis of the supporting foot 410 on the connection block 421. Then the position of the supporting foot 410 may be adjusted such that the locking hole b of the supporting foot 410 may be turned to the pin 423. The supporting foot 410 may press the pin 423 until the locking hole b of the supporting foot 410 faces the pin lock 423. The pin lock 423 may be plugged into the locking hole b of the supporting foot 410 under the force of the spring strip, thereby completing the connection of the supporting foot 410 to the connection block and the upper arm 431. When the angle of the supporting foot 410 needs to be adjusted, the pin 423 on the elastic strip 422 may be pressed down such that the pin 423 may be separated from the locking hole b of the supporting foot 410. At the same time, the supporting foot 410 may be only connected to the upper arm and the connection block by the pin shaft, the rivet or the screw in the locking hole a.
The supporting foot 410 may rotate around the locking hole a. At the same time, without the press of the supporting foot 410, the pin 423 may automatically expose the locking hole b on the connection block 421 under the force of the spring strip. When the supporting foot 410 is rotated such that the locking hole c on the supporting foot corresponds to the pin 423, the pin 423 may be plugged Date Recue/Date Received 2020-06-17 into the locking hole c of the supporting foot 410, thereby completing the angle adjustment between the supporting foot 410 and the upper arm 431.
[0104] The connection block 421 may be used as a protection of the upper arm 431 and prevent the upper arm 431 from being deformed during use. In some embodiments, the supporting foot 410 may be directly connected to the upper arm 431 and not need the protection of the connection block 421.
[0105] In some embodiments, the supporting foot, the upper arm, and the connection block may be connected via the pin shaft as long as the angle between the supporting foot and the upper arm may be adjusted, and it will not be described here.
[0106] The pole may include the upper arm and the lower arm. The connection between the upper arm and the lower arm may be retractable. A
supporting leg may be also connected to the upper arm. A connection angle between the upper arm and the supporting leg may be adjusted. The lower arm may be connected to a sleeve assembly for connecting to the front ladder and/or the rear ladder.
[0107] In some embodiments, the spring strip 422 may include a U-shaped spring strip. Two free ends of the U-shaped spring strip may have the pin 423 to improve the stability of the connection between the supporting foot and the connection block and the upper arm.
[0108] In some embodiments, an outer surface (that is a side of the supporting foot contacting with a glass floor, a wall, a window, or a roof) of the supporting foot may have a rubber layer. The supporting foot may be buffered by the rubber layer, such that the abrasion of the supporting foot may be reduced. At the same time, a friction of a contact surface of the supporting foot may be improved, and the stability of the placement may be improved.

Date Recue/Date Received 2020-06-17 10109] As referred to FIGs. 21, 23-24, in some embodiments, the connection sleeve assembly 440 may include two sliding frames 441, a fixed block 442, a handle cap 443, and a locking assembly 444. The fixed block 442 and the handle cap 443 may be disposed between the two sliding frames 441. The fixed block 442 and the handle cap 443 may form a closed loop to wrap the lower arm 432 of the pole 430. The same sides of the fixed block 442 and the two sliding frames 441 may have a card slot 445 for engaging with the sliding block 900 on the front ladder and/or the rear ladder. Preferably, the card slot 445 may include a dovetail slot. The locking assembly 444 may successively pass through the handle cap 443, the lower arm 432, and the fixed block 442 and be connected to a hole 901 on the sliding block 900. The locking assembly 444 may be configured to allow the connection sleeve assembly 440 to be locked on the hole 901 of the sliding block 900. The locking assembly 444 may have the structure as shown in FIG. 24. The locking assembly 444 may include an outer pin 463 and an inner pin 464. An end of the outer pin 463 may be connected to a locking tongue 446. The locking tongue 446 may be configured to match the hole 901 on the sliding block 900 installed on the ladder. A rack may be disposed on an inner wall of the outer pin 463. One end of the inner pin 464 may be plugged into the outer pin and connected to a gear. A compression spring 465 may be disposed between the outer pin 463 and the handle cap 443.
During the usage, the inner pin 464 may be pressed toward the inside of the handle cap 443. The inner pin 464 may drive the gear to rotate in the direction of the sliding block 900. The gear may drive the outer pin 463 to move away from the sliding block 900, such that the locking tongue 446 and the hole 901 on the sliding block may be separated from each other to complete the unlocking process with the sliding block. When the inner pin 464 is released, under a force of the compression spring 465, the outer pin 463 may be reset such that Date Recue/Date Received 2020-06-17 the locking tongue may be plugged into the card hole in the sliding block 900 again. The inner pin may also be reset simultaneously. In some embodiments, the locking assembly 444 may have the structure of the locking handle in the accessory plate assembly of the present disclosure (referring to the detailed descriptions of FIG. 15 in the present disclosure). The locking assembly 444 may also include a pin shaft, a screw or other structures for the fastening connection with the sliding block.
[0110] In some embodiments, the connection sleeve assembly may include a sliding frame 441. One side of the sliding frame may have a card slot buckled with the sliding block. The sliding frame may have the locking assembly 444 for the sliding frame and the hole 901 on the sliding block.
[0111] As referred to FIGs. 23-24, in some embodiments, the hole 901 on the sliding block 900 may include an irregular hole. For example, the hole 901 may include a large arc segment and a small arc segment. An arc radius of the large arc segment may be larger than an arc radius of the small arc segment. The locking tongue 446 of the locking assembly 444 may have a protrusion 447.
When the connection sleeve assembly is locked with the hole 901 of the sliding block, the locking tongue may automatically fall to the bottom of the hole 901.
At this time, the protrusion 447 may match the small arc segment of the hole 901.
When the unlocking is needed, the pole assembly 400 may need to be lifted up, thereby preventing unlocking by wrong operations and improving the safety of using the ladder.
[0112] As referred to FIGs. 25-28, FIG. 25 is a schematic diagram illustrating a connection between the lower arm 432 of the pole 430 and the connection sleeve assembly 440 according to an embodiment of the present disclosure.
The lower arm 432 may be parallel to the installation block 448. If the installation block 448 is plugged into the sliding block 900 parallel to the rung Date Recue/Date Received 2020-06-17 800, the pole assembly may extend outside the ladder in the direction parallel to the rung 800 (as referred to FIG. 3). If the installation block is plugged into the sliding block 900 along the length direction of the ladder, the pole assembly may extend outside the ladder along the direction of the length direction of the ladder (as referred to FIG. 20). Alternatively, the pole assembly 400 may be folded on the side of the ladder (as referred to FIG. 1 and FIG. 2).
[0113] FIG. 26 is a schematic diagram illustrating a connection of the lower arm 432 and the connection sleeve assembly 440 in another state. The lower arm 432 and the mounting seat may be perpendicular to each other in the state.

The lower arm 432 may be rotated 360 on the installation block and locked by rotating the end cap 459 in the state. If the sliding block 900 is perpendicular to the rung 800 of the ladder, the pole assembly 400 may be rotated 360 along a side of the ladder (as refer to FIG. 27). If the sliding block 900 is parallel to the rung 800 of the ladder, the pole assembly 400 may be rotated 360 along the plane formed by the outside of each pedal (as refer to FIG. 28). Therefore, in the present disclosure, the pole assembly may be rotated in different planes of the ladder to meet the usage of the pole assembly 400 in different scenarios, greatly improving the flexibility of using the ladder. At the same time, the pole may also be locked to prevent the pole from rotating during use.
[0114] As referred to FIGs. 25-26 and 29, the connection sleeve assembly 400 may include the installation block 448. The installation block 448 may have a card slot matching the sliding block 900, such that the installation block may slide on the sliding block 900. The installation block 448 may have the locking assembly for locking the installation block and the sliding block. The installation block 448 may have a mounting groove. The mounting seat 449 may be disposed inside the mounting groove. A guiding plate 451 and two mounting plates 450 may be installed on the mounting seat 449. The guiding plate 451 Date Recue/Date Received 2020-06-17 may be disposed between the two mounting plates 450. A friction ring 453 may be disposed on each of the two mounting plates 450. The two friction rings 453 may be sleeved with a connection rod 452. The connection rod may be sleeved in the friction ring 453 and rotated in the friction ring. The friction ring 453 may increase a damping when the connection rod 452 rotates, thereby improving the hand feeling when the operator rotates the connection rod 452 . The connection rod 452 may include a guiding section 4522 and two connecting sections 4521.
The two connecting sections 4521 may be rotatably connected to the friction ring 453 of the two mounting plates, respectively. The guiding section 4522 may be connected between the two connecting sections. An outer size of the guiding section may be larger than outer sizes of the two connecting sections. A cross-section of the guiding section may include a rectangle, a trapezoid, or a triangle.
The guiding section may be designed to prevent the rotation of the connection rod 452, such that the working state of the connection rod may be adjusted as needed. The connecting section may match an inner diameter of the friction ring. The guiding plate 451 may have a guiding hole 454 matching the guiding section. A return spring 455 may be disposed between the guiding section and one of the two mounting plates. One of the two connecting sections may pass through the friction ring and be connected to a fixed bracket. The fixed bracket may include a bottom plate 456 and two supporting plates 457 symmetrically disposed along the bottom plate. An outer surface of the supporting plate 457 may be an arc shape. The mounting seat 449 may have a plurality of clamping pieces 458 space from each other. Each clamping piece may be wrapped around the periphery of the supporting plate 457. The clamping piece 458 may have a rotating end cover 459. A supporting sleeve 460 may be fixedly connected or detachably connected to the lower arm 432 of the pole. Two sides of the supporting sleeve 460 may be respectively configured with a strip groove Date Recue/Date Received 2020-06-17 461. The supporting plate 457 may have a pin shaft matching the strip groove.
The bottom of the strip groove 461 may be further configured with a fixed groove.
The pole may have a fixed screw matching the fixed groove. In some embodiments, the bottom plate 462 may have a positioning hole 462 buckled with an end of the tower arm 432. A locking groove may be disposed on the periphery of the guiding section 4522. A pin buckled with the locking groove may be disposed in the guiding plate 451 to facilitate a self-locking between the guiding section and the guiding hole. In some embodiments, the guiding plate may have the guiding section whose size is larger than the guiding hole, such that the guiding section may be plugged into the guiding hole 454. For example, the guiding section may be flared. In some embodiments, the working process of the connection sleeve assembly may include: releasing the fixed screw to unlock the supporting sleeve 460 and the supporting plate 457 when the state in FIG. 26 is adjusted to the state in FIG, 25, rotating the supporting sleeve, then pushing the supporting sleeve into the supporting plate 457 until an end of the lower arm 432 is plugged into the positioning hole 462 of the bottom plate 462, and locking the fixed screw. In order to prevent the pole 430 from rotating during use, the rotating end cover 459 may be released to loosen the clamping piece 458 and the supporting plate 457. The pole 430 may be pulled outward, such that the guiding section 4522 of the connection rod 452 may be plugged into the guiding hole 454, thereby locking the positions of the connection rod, the bottom plate and the supporting plate to prevent the pole from rotating during the usage. Finally, the rotating end cover 459 may be rotated to fix the position of the bottom plate and the supporting plate on the mounting seat 449. When the state in FIG. 24 is adjusted to the state in FIG. 25, the fixed screw may be firstly released to pull the lower arm 432 outward, such that the lower arm 432 and the positioning hole 462 may be separated from each other. Then the lower arm Date Recue/Date Received 2020-06-17 432 may be rotated and the supporting sleeve 460 may be locked with the supporting plate 457 by fastening the screw. Then the rotating end cover may be released to loosen the clamping piece 458 and the supporting plate 457.
The bottom plate and the supporting plate may be under the reset action of the return spring 455, and the guiding section and the guiding hole may be separated from each other. The connection rod, the bottom plate and the supporting plate may be in a rotatable state and when they rotate to the appropriate angle, the connection rod may be pulled outward again to lock the guiding section and the guiding hole. Finally, the rotating end cover 459 may clamp the bottom plate.

Date Recue/Date Received 2020-06-17

Claims (15)

WE CLAIM:

1 . A ladder, comprising:
a front ladder and a rear ladder, a top of the front ladder and a top of the rear ladder being rotatably connected te adjust an angle between the front ladder and the rear ladder, wherein:
at least one pole assembly arranged at the front ladder and/or the rear ladder, wherein the at least one pole assembly is extended in at least one direction to adjust a size of the ladder and/or a structure of the ladder;
and/or a socket arranged at the top of the front ladder and/or the top of the rear ladder, wherein the socket is configured to receive an accessory plate assembly at least for holding goods, and is rotatable on the front ladder and/or the rear ladder to adjust an installation angle of the accessory plate assembly, wherein the socket includes an inner housing configured to receive the accessory plate assembly and an outer housing installed on the front ladder and/or rear ladder; and the inner housing is rotatable on the outer housing and locked with the outer housing when the inner housing is rotated to a preset angle.

2. The ladder of claim 1, wherein between the outer housing and the inner housing there is a rotatable connection point and at least one detachable connection point;
the rotatable connection point is configured as a center of rotation when the inner housing is rotated on the outer housing; and the detachable connection point is configured as a locking point between the inner housing and the outer housing when the inner housing is rotated to the preset angle.

Date Recue/Date Received 2021-09-01

3. The ladder of claim 2, wherein the rotatable connection point uses a pin shaft, a spindle, a rivet or a screw to allow a rotatable connection between the inner housing and the outer housing.

4. The ladder of claim 2, wherein the detachable connection point uses a pin shaft, a screw or a buckle to allow a locking between the inner housing and the outer housing.

5. The ladder of claim 4, wherein the outer housing includes a first buckle and a second buckle;
the inner housing includes a first shackle buckled with the first buckle; and the inner housing includes a second shackle buckled with the second buckle.

6. The ladder of claim 1, wherein the accessory plate assembly possesses a collapsible structure; and the accessory plate assembly includes a connection pipe for matching a hole on the inner housing, and a locking handle is disposed on the connection pipe to fasten the connection pipe and the socket.

7. The ladder of claim 6, wherein the locking handle includes a handle body rotatably connected to the connection pipe and a spring strip connected to the connection pipe;
a free end of the spring strip abuts an end of the handle body; and a pin is disposed on another end of the handle body, wherein the pin matches a locking hole on the inner housing or the outer housing.
Date Recue/Date Received 2021-09-01

8. A ladder of any one of claims 1-7, wherein the pole assembly includes a pole, and an installation direction of the pole on the front ladder and/or the rear ladder is adjustable.

9. The ladder of claim 8, wherein the pole includes an upper arm and a lower arm;
the upper arm and the lower arm are retractably connected, and a connection sleeve assembly for connecting with the front ladder and/or the rear ladder is connected to the lower arm.

10. The ladder of claim 9, wherein the connection sleeve assembly includes two sliding frames, a fixed block, a handle cap, and a locking assembly;
the fixed block and the handle cap are disposed between the two sliding frames, and together with the two sliding frames, form a circle encasing the lower arm;
the locking assembly successively passes through the handle cap, the lower arm, and the fixed block to be connected to a sliding block disposed on the ladder.

11. The ladder of claim g, wherein the sliding block is disposed on the front ladder and/or the rear ladder along at least two directions.

12. The ladder of claim 11, wherein the sliding block is disposed along a length direction of the front ladder and/or the rear ladder or along a direction parallel to a pedal of the ladder.

13. The ladder of claim 9, wherein an end of the upper arm is connected to a supporting foot in an adjustable angle.

Date Recue/Date Received 2021-09-01

14. The ladder of claim 13, wherein the upper arm is connected to the supporting foot via a connection assembly, the connection assembly includes a connection block and a spring strip, a free end of which has a pin;
the connection block, the upper arm, and the supporting foot all have at least two locking holes;
one of the locking holes of the connection block, the upper arm, and the supporting foot is configured to connect both the supporting foot and the connection block to the upper arm, wherein the supporting foot is rotatable on the connection block; and at least one of the remaining locking holes on the connection block, the upper arm, and the supporting foot is detachably connected to the supporting foot, the connection block, and the upper arm via the pin on the spring strip of the connection assembly.

15. The ladder of claim 14, wherein the spring strip of the connection assembly includes a U-shaped spring strip, and each of two free ends of the U-shaped spring strip has the pin.

Date Recue/Date Received 2021-09-01