Lifting handrails and ladders

Abstract

This utility model provides a lifting handrail and ladder, relating to the field of frame-type tools with handrails. The lifting handrail includes a handrail and a locking assembly. The handrail includes a horizontal handrail, two corner connectors, and two vertical handrails. The corner connectors are rotatably connected to the top of the vertical handrails. The locking assembly is installed at the lower end of each vertical handrail. When the vertical handrail is inserted into the connecting pipe cavity, the vertical handrail has a first rotational position and a second rotational position relative to the connecting pipe cavity. The locking assembly is used to axially lock the vertical handrail in the connecting pipe cavity when the vertical handrail is rotated to the first rotational position, and to axially unlock the vertical handrail in the connecting pipe cavity when the vertical handrail is rotated to the second rotational position. The lifting handrail provided by this utility model allows for simultaneous locking and unlocking on both sides during unlocking and locking adjustments. Furthermore, the user does not need to bend over during operation, making the entire operation more convenient and faster than single-sided unlocking.

Description

Technical Field

[0001] This utility model relates to the field of frame tools with handrails, and in particular to a lifting handrail and ladder. Background Technology

[0002] With the widespread use of ladders and other frame tools in construction, home repair, and other fields, their safety and ease of use are receiving increasing attention. Handrails, as an important component of frame tools, are primarily used to provide stable support and prevent users from falling. Traditional frame tool handrails are typically designed with a fixed height, but with the diversification of usage scenarios, height-adjustable handrails are gradually becoming a development trend.

[0003] Currently, handrails with height adjustment functions mainly achieve height adjustment through a spring pin mechanism. The working principle of this mechanism is as follows: a series of equidistant positioning holes are set on the handrail uprights, and spring-driven pins are inserted into these holes to fix the handrail in place. When height adjustment is needed, the user must first release the pin from the positioning hole. After the handrail is adjusted to the desired height, the pin automatically inserts into a new positioning hole under the action of the spring to complete the locking.

[0004] Depending on the location of the operating mechanism, existing technologies mainly fall into two categories: one is to place the control mechanism at the hinge end of the handrail column, typically using mechanical structures such as buttons, pull rings, or levers; the other is to place the control mechanism directly at the end of the handrail, generally at its lowest point. While both methods can achieve handrail height adjustment, they both have significant shortcomings in practical operation.

[0005] (1) The hinge end control mechanism requires both hands to operate the two sides of the mechanism respectively, and cannot achieve synchronous unlocking. It can only unlock one side and then unlock the other side, which is cumbersome.

[0006] (2) The operating part of the handrail end control mechanism is often located at the bottom of the handrail, which is below the limit of the position that a person can operate normally when standing. This requires the user to bend over to operate, which brings inconvenience to daily use. Utility Model Content

[0007] The purpose of this utility model is to provide a lifting handrail and ladder to alleviate the above-mentioned technical problems existing in the prior art.

[0008] To achieve the above objectives, the embodiments of this utility model adopt the following technical solutions:

[0009] In a first aspect, this utility model provides a lifting handrail applied to a frame structure having at least two connecting pipe cavities, the lifting handrail including a handrail and a locking assembly;

[0010] The handrail includes a horizontal handrail, two corner connectors and two vertical handrails; one end of each of the two corner connectors is fixed or integrally connected to both ends of the horizontal handrail, and the other end of each of the two corner connectors is rotatably connected to the top of the two vertical handrails.

[0011] A locking assembly is installed at the lower end of each of the vertical handrails; when the vertical handrail is inserted into the connecting pipe cavity, the vertical handrail has a first rotational position and a second rotational position relative to the connecting pipe cavity; the locking assembly is used to axially lock the vertical handrail to the connecting pipe cavity when the vertical handrail is rotated to the first rotational position, and to axially unlock the vertical handrail from the connecting pipe cavity when the vertical handrail is rotated to the second rotational position.

[0012] In an optional embodiment, the locking assembly includes a concentric cam locking sleeve;

[0013] The concentric cam locking sleeve has a non-circular central hole and an opening on the peripheral wall of the concentric cam locking sleeve, the opening penetrating the peripheral wall of the concentric cam locking sleeve in both the axial and radial directions.

[0014] The lower end of the vertical handrail is provided with a limiting rod segment coaxial with the vertical handrail. The radial cross section of the limiting rod segment is a concentric cam shape with the rotation center point falling on the central axis of the vertical handrail. The concentric cam locking sleeve is rotatably sleeved outside the limiting rod segment and is axially limited by the limiting rod segment.

[0015] The vertical support bar can rotate circumferentially around its own central axis relative to the concentric cam locking sleeve, so that the limiting rod segment expands the concentric cam locking sleeve in the locked state, and the limiting rod segment releases the concentric cam locking sleeve in the unlocked state.

[0016] Further optionally, the locking assembly also includes a locking protrusion;

[0017] The concentric cam locking sleeve is also provided with a clearance groove that communicates with the central hole on its peripheral wall;

[0018] The locking protrusion is provided on the outer wall of the limiting rod segment, and at least a portion of the locking protrusion is located inside the clearance groove;

[0019] When the vertical handrail is rotated to the first position, one side of the locking protrusion abuts against the inner wall of one end of the clearance groove along the circumferential direction of the concentric cam locking sleeve, and the limiting rod segment expands the concentric cam locking sleeve; when the vertical handrail is rotated to the second position, the other side of the locking protrusion abuts against the inner wall of the other end of the clearance groove along the circumferential direction of the concentric cam locking sleeve, and the limiting rod segment releases the concentric cam locking sleeve.

[0020] Further optionally, the clearance groove passes through the radial outer peripheral wall of the concentric cam locking sleeve; and / or, along the axial direction of the vertical support rod, a portion of the locking protrusion is located outside the clearance groove, one end of the clearance groove passes through the end face of the concentric cam locking sleeve facing the locking protrusion, and the other end of the clearance groove is provided with a sidewall.

[0021] In an optional embodiment, the central hole of the concentric cam locking sleeve and the radial cross-sectional outer contour of the limiting rod segment are both elliptical, and the rotation center of the radial cross-section of the limiting rod segment is the center of its elliptical outer contour.

[0022] And / or, a circumferential groove is provided on the outer peripheral wall of the limiting rod segment, and the concentric cam locking sleeve is provided inside the circumferential groove;

[0023] And / or, the locking control assembly further includes a locking shaft, which is fixedly connected to the lower end of the vertical handrail, and the limiting rod segment is formed on the locking shaft; the upper end of the locking shaft is inserted into the lower end of the limiting rod segment, and one of the two opposite side walls of the upper end of the locking shaft and the lower end of the limiting rod segment is provided with a docking groove and the other is provided with a docking protrusion, and the docking groove and the docking protrusion are interlocked.

[0024] In an optional embodiment, the top ends of the two vertical handrails are respectively inserted into one end of the corresponding corner connector, and a rotation limiting structure is also provided between the top end of each vertical handrail and the corresponding corner connector.

[0025] The rotation limiting structure includes a rotation plug, a rotation plug limiting protrusion, and two corner limiting protrusions;

[0026] The rotating plug includes a plug body and an axial positioning end component fixedly or integrally connected to the upper end of the plug body; the inner wall of the corner connector is provided with an annular positioning groove that communicates with the circumference of the vertical support rod, and at least part of the axial positioning end component is rotatably installed in the annular positioning groove; or, the outer wall of the axial positioning end component is provided with an annular positioning groove that communicates with the circumference of the vertical support rod, and the inner wall of the corner connector is provided with a positioning protrusion, which is rotatably installed in the annular positioning groove;

[0027] A rotating stop protrusion is provided on the outer wall of the plug body;

[0028] Two corner limiting protrusions are provided on the inner wall of the corner connector and are located on both sides of the rotating plug limiting protrusion along the circumference of the vertical support rod, in order to limit the rotation angle of the rotating plug limiting protrusion relative to the corner connector.

[0029] In an optional embodiment, one of the two side walls opposite to the upper end of the plug body and the corner connector is provided with a second docking groove, and the other is provided with a second docking protrusion. The second docking groove and the second docking protrusion are interlocked.

[0030] In an optional embodiment, a hand glove is fixedly connected to the upper end of each of the two vertical handrails; and / or, the corner connector is formed by two half-shells being snapped together.

[0031] Secondly, this utility model provides a ladder, including the lifting handrail described in any of the foregoing embodiments;

[0032] The ladder also includes a front frame, a rear frame, and a tread. The front frame and the rear frame each include two vertical frame rods. The two vertical frame rods of the rear frame are hinged to the two vertical frame rods of the front frame through hinges. The tread is hinged between the two vertical frame rods of the front frame and the two vertical frame rods of the rear frame.

[0033] The two vertical frame rods of the front frame are provided with connecting pipe cavities at their upper ends, and the two vertical handrails of the lifting handrail are inserted into the connecting pipe cavities of the two vertical frame rods of the front frame one by one.

[0034] In an optional embodiment, the hinge includes:

[0035] A cylindrical body is fitted onto the outside of the vertical frame rod of the front frame, and a slot is provided on one side of the cylindrical body in the circumferential direction, which runs through the circumferential wall of the cylindrical body in both the axial and radial directions;

[0036] Two clamping plates are fixedly connected to the outer wall of the cylindrical body and located on both sides of the gap, and hinge holes are provided on the clamping plates; the vertical frame of the rear frame is clamped between the two clamping plates.

[0037] A fastener passes through the hinge holes provided on the two clamping plates and the junction hole provided on the vertical frame rod of the rear frame to hinge the vertical frame rod of the rear frame to the two clamping plates.

[0038] The lifting handrail provided in this embodiment of the utility model can achieve at least the following beneficial effects:

[0039] Taking the installation of the lifting handrail inside the connecting pipe cavity at the upper end of the two vertical frame rods of the front frame of the ladder as an example, the specific structure of the lifting handrail will be described and explained:

[0040] In use, unfold the front and rear frames of the ladder from the closed state to the usable state and place them on the ground. The user stands on the side of the front frame, steps on the bottom step, and holds the two vertical handrails with both hands. Simultaneously rotate the two vertical handrails inward (towards each other) to rotate them from the first rotation position to the second rotation position. The locking component unlocks the vertical handrails axially into the connecting pipe cavity, allowing the user to lift the handrails upward. After raising the handrails to the appropriate position, simultaneously rotate the two vertical handrails outward (back to back) with both hands to rotate them to the first rotation position. The locking component then locks the vertical handrails axially into the connecting pipe cavity to lock the lifting handrails.

[0041] Similarly, when the handrail needs to be lowered, hold the two vertical handrails with both hands and rotate them inward (towards each other) to move them from the first rotation position to the second rotation position. The locking component will then unlock the vertical handrails axially into the connecting pipe cavity, allowing the user to press down on the handrail. After lowering the handrail to the desired position, rotate the two vertical handrails outward (towards each other) with both hands to move them to the first rotation position. The locking component will then lock the vertical handrails axially into the connecting pipe cavity to lock the handrail.

[0042] Alternatively, when both hands rotate the two vertical handrails outward (back to back) simultaneously, the vertical handrails rotate from the first rotation position to the second rotation position, and the locking control component unlocks the vertical handrails axially into the connecting pipe cavity; at the same time, when both hands rotate the two vertical handrails inward (towards each other), the vertical handrails rotate to the first rotation position, and the locking control component locks the vertical handrails axially into the connecting pipe cavity to lock the lifting handrail.

[0043] The lifting handrail provided in this embodiment is installed on the frame structure of the ladder, allowing the handrail of the tool ladder to be raised and lowered for adjustment. The ladder can adapt to different leaning heights and tilt angles. During the unlocking and locking adjustment of the lifting handrail, both sides can be locked and unlocked simultaneously. Furthermore, the user does not need to bend over during the operation. The entire operation process is more convenient and faster than unlocking from one side, and it also avoids the problem of ladder instability when unlocking from one side.

[0044] It should be noted that the lifting handrail provided in this embodiment can be applied not only to ladders, but also to other frame structures, achieving the same functional effect.

[0045] The ladder provided in this embodiment of the present invention includes the lifting handrail provided in the first aspect. Therefore, the ladder provided in this embodiment of the present invention can achieve all the beneficial effects that the lifting handrail provided in the first aspect can achieve. Attached Figure Description

[0046] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0047] Figure 1 A schematic diagram of the overall structure of the lifting handrail provided in this embodiment of the utility model;

[0048] Figure 2 for Figure 1 A magnified view of the structure of region A1 in the middle;

[0049] Figure 3 An axonometric perspective view of the rotation limiting structure in the lifting handrail provided in this embodiment of the utility model;

[0050] Figure 4 for Figure 3 A schematic diagram of the overall structure of the rotary stop in the rotary limiting structure shown;

[0051] Figure 5 A cross-sectional view of the installation structure of the lifting handrail installed in the ladder connecting pipe cavity, provided in an embodiment of this utility model;

[0052] Figure 6 for Figure 5 A magnified view of the structure of region B1 in the middle;

[0053] Figure 7 for Figure 6 Cross-sectional view along line CC;

[0054] Figure 8 for Figure 1 A magnified view of the structure of region A2 in the middle;

[0055] Figure 9 for Figure 5 A magnified view of the structure of region B2 in the middle;

[0056] Figure 10 A schematic diagram of the overall structure of the concentric cam locking sleeve in the locking assembly of the lifting handrail provided in this embodiment of the utility model;

[0057] Figure 11 A schematic diagram of the overall structure of the locking shaft in the locking control assembly of the lifting handrail provided in this embodiment of the utility model;

[0058] Figure 12 A schematic diagram of the assembly structure of the locking shaft and the concentric cam locking sleeve in the locking control assembly of the lifting handrail provided in this embodiment of the utility model;

[0059] Figure 13A To rotate the vertical support rod 13 to the first rotation position and lock it axially within the connecting pipe cavity, Figure 12 EE-directed sectional view;

[0060] Figure 13B To rotate the vertical support rod 13 to the second rotation position, when the vertical support rod 13 is axially unlocked into the connecting pipe cavity, Figure 12 EE-directed sectional view;

[0061] Figure 14 A schematic diagram of the overall structure of the vertical handrail in the lifting handrail provided in this embodiment of the utility model;

[0062] Figure 15 for Figure 14 A magnified view of the structure of region D1 in the middle;

[0063] Figure 16 for Figure 14 A magnified view of the structure of region D2 in the middle;

[0064] Figure 17 A schematic diagram of the ladder in the lowered state of the lifting handrail, provided for an embodiment of this utility model;

[0065] Figure 18 A schematic diagram of the ladder with the handrail raised, provided in an embodiment of the present invention.

[0066] Figure 19 This is a schematic diagram of the overall structure of the hinge component in the ladder provided in this embodiment of the utility model.

[0067] Icons: 11-Horizontal handrail; 12-Corner connector; 121-Corner limiting protrusion; 13-Vertical handrail; L-Limiting rod segment; L1-Circumferential groove; L2-Locking protrusion; 2-Concentric cam locking sleeve; 201-Center hole; 202-Opening; 203-Allowing groove; 3-Locking shaft; 41-Matching groove one; 42-Matching protrusion one; 5-Rotating plug; 51-Plug body; 511-Rotating plug limiting protrusion; 52-Positioning end component; 6-Annular positioning groove; 71-Matching groove two; 72-Matching protrusion two; 8-Handle glove;

[0068] 100 - Connecting pipe cavity; 110 - Front frame; 120 - Rear frame; 130 - Pedal; 9 - Hinge; 91 - Cylindrical body; 911 - Gap; 912 - Buckle protrusion; 92 - Clamping plate. Detailed Implementation

[0069] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0070] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0071] It should be noted that similar labels and letters in the accompanying drawings indicate similar items. Therefore, once an item is defined in one accompanying drawing, it does not need to be further defined and explained in subsequent accompanying drawings.

[0072] In the description of this utility model, it should be noted that:

[0073] Unless otherwise expressly specified and limited, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0074] The terms "upper," "lower," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "horizontal" and "vertical" do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly inclined. For example, when the front frame and rear frame of the ladder are unfolded, the "vertical handrail" and "vertical frame" are at an angle inclined to the horizontal plane, but are respectively called "vertical handrail" and "vertical frame" relative to the horizontally unfolded treads. The angle between the "horizontal handrail" and the "vertical handrail" is not strictly defined as 90 degrees, and can also be other non-perpendicular preset angles, that is, a slight inclination between the "horizontal handrail" and the "vertical handrail" is allowed.

[0075] The terms “component one,” “component two,” “first,” “second,” etc., are used only for distinguishing descriptions and do not indicate totality or relative position in time and / or space, nor should they be construed as indicating or implying relative importance.

[0076] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the features of the following embodiments and optional embodiments can be combined with each other.

[0077] Example 1

[0078] This embodiment provides a lifting handrail, which is applied to a frame structure having at least two connecting pipe cavities. This frame structure can be a tool ladder frame, a trolley frame, a suitcase frame, or another tool frame structure. For example... Figure 5 , Figure 17 and Figure 18 As shown, this embodiment takes the installation of the lifting handrail inside the connecting pipe cavity 100 at the upper end of the two vertical frame rods of the front frame 110 of the ladder as an example to describe the specific structure of the lifting handrail:

[0079] Reference Figure 1 , Figure 2 and Figure 5 Specifically, the lifting handrail includes at least a handrail and a locking assembly, wherein: the handrail includes a horizontal handrail 11, two corner connectors 12, and two vertical handrails 13; one end of each of the two corner connectors 12 is fixedly or integrally connected to both ends of the horizontal handrail 11, and the other end of each of the two corner connectors 12 is rotatably connected to the top ends of the two vertical handrails 13. The locking assembly is installed at the lower end of each vertical handrail 13; when the vertical handrail 13 is inserted into the connecting pipe cavity 100, the vertical handrail 13 has a first rotation position and a second rotation position relative to the connecting pipe cavity 100; the locking assembly is used to axially lock the vertical handrail 13 to the connecting pipe cavity 100 when the vertical handrail 13 is rotated to the first rotation position, and to axially unlock the vertical handrail 13 from the connecting pipe cavity 100 when the vertical handrail 13 is rotated to the second rotation position.

[0080] Reference Figure 17 and Figure 18When in use, unfold the front frame 110 and rear frame 120 of the ladder from the closed state to the use state and place them on the ground. The user stands on the side of the front frame 110, steps on the bottom step 130, and holds the two vertical handrails 13 with both hands. At the same time, rotate the two vertical handrails 13 inward (towards each other) so that the vertical handrails 13 rotate from the first rotation position to the second rotation position. The locking component unlocks the vertical handrails 13 axially into the connecting pipe cavity 100, and the user can lift the handrail upward. After the handrail is raised to a suitable position, rotate the two vertical handrails 13 outward (back to back) with both hands at the same time so that the vertical handrails 13 rotate to the first rotation position. The locking component locks the vertical handrails 13 axially into the connecting pipe cavity 100 to lock the lifting handrail.

[0081] Similarly, when the handrail needs to be lowered, hold the two vertical handrails 13 with both hands and rotate them inward (towards each other) to move them from the first rotation position to the second rotation position. The locking component will then unlock the vertical handrails 13 axially into the connecting pipe cavity 100, allowing the user to press down on the handrail. After lowering the handrail to the appropriate position, rotate the two vertical handrails 13 outward (towards each other) with both hands to move them to the first rotation position. The locking component will then lock the vertical handrails 13 axially into the connecting pipe cavity 100 to lock the handrail.

[0082] Alternatively, when both hands rotate the two vertical handrails 13 outward (back to back) simultaneously, the vertical handrails 13 rotate from the first rotation position to the second rotation position, and the locking control assembly unlocks the vertical handrails 13 axially into the connecting pipe cavity 100; at the same time, when both hands rotate the two vertical handrails 13 inward (towards each other), the vertical handrails 13 rotate to the first rotation position, and the locking control assembly locks the vertical handrails 13 axially into the connecting pipe cavity 100 to lock the lifting handrail.

[0083] The lifting handrail provided in this embodiment is installed on the frame structure of the ladder, allowing the handrail of the tool ladder to be raised and lowered for adjustment. The ladder can adapt to different leaning heights and tilt angles. During the unlocking and locking adjustment of the lifting handrail, both sides can be locked and unlocked simultaneously. Furthermore, the user does not need to bend over during the operation. The entire operation process is more convenient and faster than unlocking from one side, and it also avoids the problem of ladder instability when unlocking from one side.

[0084] It should be noted that the lifting handrail provided in this embodiment can be applied not only to ladders, but also to other frame structures, achieving the same functional effect.

[0085] In this embodiment, there are several optional structures for the specific design of the keyhole assembly, such as, but not limited to:

[0086] Reference Figures 8 to 12 ,as well as Figure 13A , Figure 13B In an optional embodiment of this example, the locking assembly includes a concentric cam locking sleeve 2. Specifically, the concentric cam locking sleeve 2 has a non-circular central hole 201, and an opening 202 is provided on the peripheral wall of the concentric cam locking sleeve 2, which penetrates the peripheral wall of the concentric cam locking sleeve 2 axially and radially. The lower end of the vertical support rod 13 is provided with a limiting rod segment L coaxial with the vertical support rod 13. The radial cross section of the limiting rod segment L is in the shape of a concentric cam with its rotation center point falling on the central axis of the vertical support rod 13. The concentric cam locking sleeve 2 is rotatably sleeved outside the limiting rod segment L and is axially limited by the limiting rod segment L. The vertical support rod 13 can rotate circumferentially relative to the concentric cam locking sleeve 2 around its own central axis, so that the limiting rod segment L expands the concentric cam locking sleeve 2 in the locked state, and the limiting rod segment L releases the concentric cam locking sleeve 2 in the unlocked state.

[0087] In use, the user rotates the vertical handle 13, causing the locking protrusion L2 to rotate within the clearance groove 203 of the concentric cam locking sleeve 2, thereby enabling the locking component to switch between different states.

[0088] Specifically: When the vertical support rod 13 is inserted into the connecting tube cavity 100, the concentric cam locking sleeve 2 has an initial frictional force f in contact with the inner wall of the connecting tube cavity 100; the specific assembly method is as follows: in the unlocked state, press the concentric cam locking sleeve 2 radially inward, so that the inner wall of the concentric cam locking sleeve 2 is tightly attached to the outer wall of the limiting rod segment L, so as to insert the concentric cam locking sleeve 2 into the connecting tube cavity 100, and ensure that after the concentric cam locking sleeve 2 is released, the concentric cam locking sleeve 2 generates a positive pressure on the inner wall of the connecting tube cavity 100, so that there is an initial frictional force f between the outer wall of the concentric cam locking sleeve 2 and the inner wall of the connecting tube cavity 100 (this can be achieved by designing the maximum outer diameter of the concentric cam locking sleeve 2 in the free state to be smaller than the inner diameter of the connecting tube cavity 100, or by setting other protruding ribs or other structures on the outer peripheral wall of the concentric cam locking sleeve 2 to achieve frictional fit between the outer wall of the concentric cam locking sleeve 2 and the inner wall of the connecting tube cavity 100 after assembly).

[0089] like Figure 13A As shown, when the user rotates the vertical handle 13 to the locked state (or the vertical handle 13 is preset to be in the locked state), the concentric cam locking sleeve 2 is expanded by the cam-shaped limiting rod segment L, and the opening 202 further expands. A large frictional force is generated between the concentric cam locking sleeve 2 and the limiting rod segment L, and the vertical handle 13 is locked in the connecting tube cavity 100. When the user rotates the vertical handle 13 in the unlocking direction, as... Figure 13BAs shown, the locking protrusion L2, with a radial cross-section in the shape of a concentric cam, rotates with the vertical handle 13 to the unlocked state. The concentric cam locking sleeve 2 and the limiting rod segment L are in a released state, and the vertical handle 13 can be freely raised and lowered. At this time, the user only needs to apply a force slightly greater than the initial frictional force f to lift or press the vertical handle and the concentric cam locking sleeve 2 relative to the corresponding pipe cavity 100. After the lifting or lowering is in place, the user rotates the vertical handle 13 to the locked state, such as... Figure 13A As shown, the concentric cam locking sleeve 2 is expanded by the limiting rod segment L with a radial cross section in the shape of a concentric cam, and the opening 202 is further expanded. A large frictional force is generated between the concentric cam locking sleeve 2 and the limiting rod segment L, and the vertical support rod 13 is locked in the connecting tube cavity 100.

[0090] In this optional embodiment, the concentric cam locking sleeve 2 is fitted outside the limiting rod segment L with a radial cross section in the shape of a concentric cam. Through the opening 202, it achieves frictional engagement with the inner wall of the connecting tube cavity 100 and the cam-shaped limiting rod segment L to achieve rapid locking and unlocking. It has the beneficial effects of compact structure, simple operation, and stable and reliable locking and releasing functions.

[0091] Reference Figures 8 to 12 ,as well as Figure 13A , Figure 13B In a further optional embodiment, the locking assembly further includes a locking protrusion L2. A clearance groove 203 is provided on the peripheral wall of the concentric cam locking sleeve 2, which communicates with the central hole 201 of the concentric cam locking sleeve 2. The locking protrusion L2 is located on the outer wall of the limiting rod segment L, and at least a portion of the locking protrusion L2 is located inside the clearance groove 203. The vertical support rod 13 is circumferentially rotatable relative to the concentric cam locking sleeve 2 around its own central axis, and in the locked state as... Figure 13A As shown, when the vertical support bar 13 rotates to the first position, one side wall of the locking protrusion L2 abuts against the inner wall S1 of one end of the concentric cam locking sleeve 2 along the circumferential direction of the clearance groove 203, and the limiting rod segment L expands the concentric cam locking sleeve 2; in the unlocked state and as Figure 13B As shown, when the vertical support bar 13 rotates to the second position, the other side wall of the locking protrusion L2 abuts against the inner wall S2 of the other end of the relief groove 203 along the circumferential direction of the concentric cam locking sleeve 2, and the limiting rod segment L releases the concentric cam locking sleeve 2.

[0092] In use, the user rotates the vertical handle 13, causing the locking protrusion L2 to rotate within the clearance groove 203 of the concentric cam locking sleeve 2, thereby switching the locking component between different states. Specifically: when the vertical handle 13 is inserted into the connecting tube cavity 100, the concentric cam locking sleeve 2 has an initial frictional force f in contact with the inner wall of the connecting tube cavity 100; such as Figure 13AAs shown, when the user rotates the vertical handrail 13 to the first position (or the vertical handrail 13 is preset to the first position), the locking protrusion L2 rotates with the vertical handrail 13 until it abuts against the inner wall S1 of one end of the concentric cam locking sleeve 2 along the circumferential direction of the clearance groove 203. The concentric cam locking sleeve 2 is expanded by the limiting rod segment L with a radial cross-section in the shape of a cam, and the opening 202 further expands. A large frictional force is generated between the concentric cam locking sleeve 2 and the limiting rod segment L, and the vertical handrail 13 is locked in the connecting tube cavity 100. When the user rotates the vertical handrail 13 to the second position, as... Figure 13B As shown, the locking protrusion L2, with a radial cross-section in the shape of a cam, rotates with the vertical arm 13 until it abuts against the inner wall S2 of the other end of the concentric cam locking sleeve 2 along the circumferential direction of the clearance groove 203. The concentric cam locking sleeve 2 and the limiting rod segment L are in a released state, and the vertical arm 13 can be raised and lowered freely. At this time, the user only needs to apply a force slightly greater than the initial friction force f to lift or press the vertical arm and the concentric cam locking sleeve 2 relative to the connecting pipe cavity 100. After the vertical arm 13 is raised or lowered to the first position, the user rotates the vertical arm 13 back to the first position, and the vertical arm 13 is locked in the connecting pipe cavity 100.

[0093] In this optional embodiment, by providing the locking protrusion L2 and the clearance groove 203, it can be used to maintain the locked or unlocked state after the vertical handrail 13 has been rotated into place. Figure 13A As shown, when the vertical handrail rotates to the first position, the locking protrusion L2 rotates with the vertical handrail 13 until it abuts against the inner wall S1 of one end of the concentric cam locking sleeve 203, which is circumferentially upward. At this point, if the vertical handrail continues to rotate in the locking direction, there will be no problem of changing from the locked state to the unlocked state. Therefore, a stable locking relationship can be ensured at this time. Figure 13B As shown, when the vertical handrail rotates to the second position, the locking protrusion L2 rotates with the vertical handrail 13 until it abuts against the inner wall S2 of the other end of the concentric cam locking sleeve 2 along the circumferential direction of the clearance groove 203. At this time, if the vertical handrail 13 continues to rotate in the unlocking direction, it is only possible for the vertical handrail 13, along with the limiting rod segment L and the concentric cam locking sleeve 2, to rotate simultaneously relative to the connecting tube cavity 100. However, it will not cause the limiting rod segment L and the concentric cam locking sleeve 2 to change from the unlocked state to the locked state. Thus, it can be ensured that the vertical handrail 13 is in a liftable unlocked relationship at this time. Therefore, this optional embodiment enhances the reliability of the lifting handrail in both the unlocked and locked states by designing the locking protrusion L2 and the clearance groove 203.

[0094] In addition, in this optional embodiment, by setting the locking protrusion L2 and the clearance groove 203, positioning references are provided for the unlocked state and the locked state, respectively. After designing this positioning, the rotation angle when switching between the unlocked state and the locked state is determined to be within a relatively small angle range, making it easier for users to operate and improving the user experience.

[0095] In particular, in other optional embodiments of this example, the above-mentioned clearance groove 203 and locking protrusion L2 may not be provided. However, when the lifting handrail is applied to a high-safety frame structure such as a ladder, it is preferable to adopt the structure of the above-described embodiment, designing the locking protrusion L2 and the corresponding clearance groove 203 to improve the stability of the state in the locked or unlocked state. In the locked state, it can improve the positioning reliability of the handrail height position. In the unlocked state, it can avoid the problem of jamming in the lifting adjustment of the handrail caused by repeated locking and unlocking due to incorrect locking.

[0096] In this optional embodiment, the aforementioned clearance groove 203 penetrates the radial outer peripheral wall of the concentric cam locking sleeve 2; and / or, along the axial direction of the vertical support rod 13, a portion of the locking protrusion L2 is located outside the clearance groove 203, one end of the clearance groove 203 penetrates the end face of the concentric cam locking sleeve 2 facing the locking protrusion L2, and the other end of the clearance groove 203 is provided with a sidewall. This optional embodiment allows the clearance groove 203 to accommodate locking protrusions L2 of various sizes, thereby reducing the assembly precision between the clearance groove 203 and the locking protrusion L2, allowing for greater machining errors, and facilitating improved assembly and manufacturing efficiency and reduced product defect rates.

[0097] Optionally, such as Figure 13A and Figure 13B As shown, the outer contours of the radial cross-section of the concentric cam locking sleeve 2, the central hole 201, and the limiting rod segment L are all elliptical. The rotation center of the radial cross-section of the limiting rod segment L is the center of its elliptical outer contour. This allows the concentric cam locking sleeve 2 to achieve radial double-sided locking between the outer wall of its two sides along the long axis of its elliptical central hole 201 and the inner wall of the connecting tube cavity 100, and between the inner wall and the outer wall of the cam-shaped limiting rod segment L. This provides a larger contact surface and constraint force, thereby further improving the locking force of the concentric cam locking sleeve 2 on the vertical rod 13.

[0098] Optionally, the limiting rod segment L can be fixedly connected or integrally formed on the vertical handrail 13. For ease of manufacturing and maintenance, in some optional embodiments, the locking assembly further includes a locking shaft 3, which is fixedly connected to the lower end of the vertical handrail 13, and the limiting rod segment L is formed on the locking shaft 3.

[0099] Furthermore, referring to Figure 11 , Figure 14 and Figure 16In an optional embodiment of this invention, the upper end of the locking shaft 3 is inserted into the lower end of the limiting rod segment L. One of the opposite side walls of the upper end of the locking shaft 3 and the lower end of the limiting rod segment L is provided with a mating groove 41, and the other with a mating protrusion 42. The mating groove 41 and the mating protrusion 42 are interlocked. This mating method is simple and convenient, and provides strong stability. It also prevents the upper end of the locking shaft 3 and the lower end of the limiting rod segment L from rotating relative to each other, making the operation more reliable. It should be noted that the locking component in this embodiment is not limited to a mating structure where the central hole 201 of the concentric cam locking sleeve 2 and the radial cross-sectional outer contour of the limiting rod segment L are both elliptical. In this embodiment, other component forms are also possible, such as, but not limited to, using an eccentric principle to design the locking sleeve and the cam-shaped limiting rod segment L. The cam shape can be teardrop-shaped or other shapes. In use, the user rotates the vertical support rod 13 to make the locking protrusion L2 abut against or disengage from the inner wall of the eccentric locking sleeve, thereby realizing the switching of the locking component between different states. However, preferably, the aforementioned mating structure where the central hole 201 of the concentric cam locking sleeve 2 and the radial cross-sectional outer contour of the limiting rod segment L are both elliptical is used in combination with the locking protrusion L2 to achieve the function of double-sided radial locking of the concentric cam locking sleeve 2 when the vertical support rod 13 is rotated to the first position, ensuring the locking reliability in the locked state.

[0100] In this embodiment, the concentric cam locking sleeve 2 is rotatably sleeved outside the limiting rod segment L and axially limited by the limiting rod segment L. There are various specific axial limiting methods, including but not limited to providing upper and lower limiting protrusions on the outer wall of the limiting rod segment L for limiting, or limiting in other ways. This limiting ensures that the concentric cam locking sleeve 2 can be raised and lowered synchronously with the vertical handrail 13, and ensures that when the vertical handrail 13 rotates circumferentially relative to the concentric cam locking sleeve 2, the locking protrusion L2 can abut against or disengage from the inner wall of the central hole 201 of the concentric cam locking sleeve 2. For example, but not limited to, refer to... Figures 8 to 11 A circumferential groove L1 is provided on the outer peripheral wall of the limiting rod segment L. The concentric cam locking sleeve 2 and the locking protrusion L2 are both located inside the circumferential groove L1. This minimizes the radial clearance between the limiting rod segment L and the connecting tube cavity 100, ensuring that the locking protrusion L2 is always located inside the circumferential groove L1. This ensures that the limiting rod segment L and the concentric cam locking sleeve 2 will not disengage during rotation, thus ensuring the reliability of the locking and unlocking functions. At the same time, it ensures that the limiting fit between the locking protrusion L2 and the clearance groove 203 is not affected by axial movement during rotation.

[0101] Reference Figures 2 to 7In an optional embodiment of this example, the top ends of the two vertical handrails 13 are respectively inserted into the interior of one end of the corresponding corner connector 12, and a rotation limiting structure is also provided between the top end of each vertical handrail 13 and the corresponding corner connector 12. The rotation limiting structure includes a rotation plug 5, a rotation plug limiting protrusion 511, and two corner limiting protrusions 121. Specifically, the rotation plug 5 includes a plug body 51 and an axial positioning end component 52 fixedly or integrally connected to the upper end of the plug body 51; the inner wall of the corner connector 12 is provided with an annular positioning groove 6 that communicates circumferentially with the vertical handrail 13, and at least part of the axial positioning end component 52 is rotatably installed in the annular positioning groove 6, or the outer wall of the axial positioning end component 52 is provided with an annular positioning groove that communicates circumferentially with the vertical handrail 13, and the inner wall of the corner connector 12 is provided with a positioning protrusion, which is rotatably installed in the annular positioning groove (this variable structure is not shown). The rotation plug limiting protrusion 511 is provided on the outer wall of the plug body 51. Two corner limiting protrusions 121 are provided on the inner wall of the corner connector 12 and are arranged on both sides of the rotation block limiting protrusion 511 along the circumference of the vertical support rod 13, in order to limit the rotation angle of the rotation block limiting protrusion 511 relative to the corner connector 12.

[0102] In this optional implementation, the two corner limiting protrusions 121 can cooperate with the rotation blocking limiting protrusion 511 to achieve the rotation limiting function of unlocking and locking, making it easier for users to judge the current position of the vertical handrail 13 and improving the user experience.

[0103] Reference Figures 4 to 6 ,as well as Figure 14 and Figure 15 In an optional embodiment of this invention, one of the two side walls opposite to the upper end of the plug body 51 and the corner connector 12 is provided with a mating groove 71 and a mating protrusion 72, and the mating groove 71 and the mating protrusion 72 are interlocked. This connection method is simple, reliable and easy to manufacture.

[0104] Reference Figure 2 and Figure 6 In an optional embodiment of this invention, handle gloves 8 are fixedly connected to the upper ends of the two vertical handrails 13 respectively to increase the friction force when the vertical handrails 13 rotate, making them easier to operate and preventing slippage. In an optional embodiment of this invention, the corner connector 12 is formed by two half-shells being snapped together, a structure that is easier to manufacture.

[0105] Second aspect

[0106] This embodiment also provides a ladder, as shown in the reference. Figure 17 and Figure 18The ladder includes a lifting handrail provided in any optional embodiment of the first aspect, and also includes a front frame 110, a rear frame 120, and a step 130. The front frame 110 and the rear frame 120 each include two vertical frame rods. The two vertical frame rods of the rear frame 120 are hinged to the two vertical frame rods of the front frame 110 in a one-to-one correspondence via hinges 9. The step 130 is hinged between the two vertical frame rods of the front frame 110 and the two vertical frame rods of the rear frame 120. The two vertical frame rods of the front frame 110 have connecting pipe cavities 100 at least at their upper ends. The two vertical handrails 13 of the lifting handrail are inserted into the connecting pipe cavities 100 of the two vertical frame rods of the front frame 110 in a one-to-one correspondence.

[0107] Reference Figure 19 In an optional embodiment of this example, the hinge 9 includes a cylindrical body 91, two clamping plates 92, and at least one fixing member. Specifically, the cylindrical body 91 is fitted onto the outside of the vertical frame rod of the front frame 110, and a slot 911 is provided on one side of the cylindrical body 91 in the circumferential direction, penetrating the circumferential wall of the cylindrical body 91 axially and radially. The two clamping plates 92 are fixedly connected to the outer wall of the cylindrical body 91 and located on both sides of the slot 911, and hinge holes are provided on the clamping plates 92. The vertical frame of the rear frame 120 is clamped between the two clamping plates 92. The fixing member passes through the hinge holes provided on the two clamping plates 92 and the junction holes provided on the vertical frame rod of the rear frame 120 to hinge the vertical frame rod of the rear frame 120 to the two clamping plates 92. The fixing member can be a bolt assembly, a limiting pin, or other structural components. This optional embodiment has a simple structure, is easy to assemble, and provides high stability after assembly.

[0108] To further facilitate installation, optionally, such as Figure 19 As shown, one of the inner wall of the cylindrical body 91 and the outer wall of the vertical frame rod of the front frame 110 is provided with a buckle protrusion 912, and the other is provided with an assembly groove. After the cylindrical body 91 is fitted onto the outside of the vertical frame rod of the front frame 110, the buckle protrusion 912 is inserted into the assembly groove. This assembly method can improve the installation efficiency and at the same time ensure the stability and reliability of the assembly structure between the hinge 9 and the vertical frame rod of the front frame 110.

[0109] For a more specific structure and the effects that can be achieved by the lifting handrail provided in the ladder in this embodiment, please refer to the optional or preferred embodiments in the first aspect.

[0110] Finally, it should be noted that:

[0111] 1. In this specification, “and / or” means that the first feature before “and / or” and the second feature after “and / or” include the following specific setting methods: (1) setting only the first feature and not setting the second feature; (2) setting only the second feature and not setting the first feature; (3) setting both the first feature and the second feature simultaneously.

[0112] 2. The above embodiments and optional implementations in this specification are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing optional implementations, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model. Furthermore, it is emphasized again that, in the absence of conflict, the features of the embodiments and optional implementations in the embodiments in this specification can be combined with each other.

Claims

1. A lift handrail for use in a frame structure having at least two docking tube cavities (100), characterized in that, The lifting handrail includes: The handrail includes a horizontal handrail (11), two corner connectors (12) and two vertical handrails (13); one end of each of the two corner connectors (12) is fixed or integrally connected to both ends of the horizontal handrail (11), and the other end of each of the two corner connectors (12) is rotatably connected to the top end of the two vertical handrails (13). A locking assembly is installed at the lower end of each of the vertical handrails (13); when the vertical handrail (13) is inserted into the connecting tube cavity (100), the vertical handrail (13) has a first rotation position and a second rotation position relative to the connecting tube cavity (100); the locking assembly is used to lock the vertical handrail (13) axially in the connecting tube cavity (100) when the vertical handrail (13) is rotated to the first rotation position, and to unlock the vertical handrail (13) axially in the connecting tube cavity (100) when the vertical handrail (13) is rotated to the second rotation position.

2. The lifting handrail according to claim 1, characterized in that, The locking assembly includes a concentric cam locking sleeve (2); The concentric cam locking sleeve (2) has a non-circular central hole (201), and an opening (202) is provided on the peripheral wall of the concentric cam locking sleeve (2). The opening (202) penetrates the peripheral wall of the concentric cam locking sleeve (2) in both the axial and radial directions. The lower end of the vertical handrail (13) is provided with a limiting rod segment (L) coaxial with the vertical handrail (13). The radial cross section of the limiting rod segment (L) is a concentric cam shape with the rotation center point falling on the central axis of the vertical handrail (13). The concentric cam locking sleeve (2) is rotatably sleeved outside the limiting rod segment (L) and is axially limited by the limiting rod segment (L). The vertical support rod (13) can rotate circumferentially around its own central axis relative to the concentric cam locking sleeve (2), so that the limiting rod segment (L) expands the concentric cam locking sleeve in the locked state, and the limiting rod segment (L) releases the concentric cam locking sleeve (2) in the unlocked state.

3. The lifting handrail according to claim 2, characterized in that, The locking assembly also includes a locking protrusion (L2); The concentric cam locking sleeve (2) is also provided with a relief groove (203) that communicates with the central hole (201) on its peripheral wall. The locking protrusion (L2) is provided on the outer wall of the limiting rod segment (L), and at least part of the locking protrusion (L2) is located inside the clearance groove (203); When the vertical handrail (13) is rotated to the first position, one side wall of the locking protrusion (L2) abuts against the inner wall of one end of the clearance groove (203) along the circumferential direction of the concentric cam locking sleeve (2), and the limiting rod segment (L) expands the concentric cam locking sleeve (2); when the vertical handrail (13) is rotated to the second position, the other side wall of the locking protrusion (L2) abuts against the inner wall of the other end of the clearance groove (203) along the circumferential direction of the concentric cam locking sleeve (2), and the limiting rod segment (L) releases the concentric cam locking sleeve (2).

4. The lifting handrail according to claim 3, characterized in that, The clearance groove (203) penetrates the radial outer peripheral wall of the concentric cam locking sleeve (2); and / or, along the axial direction of the vertical support rod (13), part of the locking protrusion (L2) is located outside the clearance groove (203), one end of the clearance groove (203) penetrates the end face of the concentric cam locking sleeve (2) facing the locking protrusion (L2), and the other end of the clearance groove (203) is provided with a side wall.

5. The lift bench of claim 2, wherein The central hole (201) of the concentric cam locking sleeve (2) and the radial cross-sectional outer contour of the limiting rod segment (L) are both elliptical, and the rotation center of the radial cross-section of the limiting rod segment (L) is the center of its elliptical outer contour. And / or, a circumferential groove (L1) is provided on the outer peripheral wall of the limiting rod segment (L), and the concentric cam locking sleeve (2) is provided inside the circumferential groove (L1); And / or, the locking assembly further includes a locking shaft (3), which is fixedly connected to the lower end of the vertical handrail (13), and the limiting rod segment (L) is formed on the locking shaft (3); the upper end of the locking shaft (3) is inserted into the lower end of the limiting rod segment (L), and one of the two side walls opposite to the upper end of the locking shaft (3) and the lower end of the limiting rod segment (L) is provided with a docking groove (41) and the other is provided with a docking protrusion (42), and the docking groove (41) and the docking protrusion (42) are interlocked.

6. The lifting handrail according to any one of claims 1-5, characterized in that, The top ends of the two vertical handrails (13) are respectively inserted into one end of the corresponding corner connector (12), and a rotation limiting structure is also provided between the top end of each vertical handrail (13) and the corresponding corner connector (12); The rotation limiting structure includes: The rotating plug (5) includes a plug body (51) and an axial positioning end component (52) fixed or integrally connected to the upper end of the plug body (51); the inner wall of the corner connector (12) is provided with an annular positioning groove (6) that is circumferentially connected to the vertical support rod (13), at least part of the axial positioning end component (52) is rotatably installed in the annular positioning groove (6), or the outer wall of the axial positioning end component (52) is provided with an annular positioning groove that is circumferentially connected to the vertical support rod (13), and the inner wall of the corner connector (12) is provided with a positioning protrusion, which is rotatably installed in the annular positioning groove; A rotating plug limiting protrusion (511) is provided on the outer wall of the plug body (51); Two corner limiting protrusions (121) are provided on the inner wall of the corner connector (12) and on both sides of the rotating block limiting protrusion (511) along the circumference of the vertical support rod (13) to limit the rotation angle of the rotating block limiting protrusion (511) relative to the corner connector (12).

7. The lifting handrail according to claim 6, characterized in that, The upper end of the plug body (51) and the two side walls opposite to the corner connector (12) are provided with a second docking groove (71) on one side and a second docking protrusion (72) on the other side. The second docking groove (71) and the second docking protrusion (72) are interlocked.

8. The elevated handrail of claim 6, wherein, A glove (8) is fixedly connected to the upper end of each of the two vertical handrails (13); and / or, the corner connector (12) is formed by two halves of the shell being snapped together.

9. A ladder, characterized in that Includes the lifting handrail as described in any one of claims 1 to 6; The ladder also includes a front frame (110), a rear frame (120), and a step (130). The front frame (110) and the rear frame (120) each include two vertical frame rods. The two vertical frame rods of the rear frame (120) are hinged to the two vertical frame rods of the front frame (110) in a one-to-one correspondence through hinges (9). The step (130) is hinged between the two vertical frame rods of the front frame (110) and the two vertical frame rods of the rear frame (120). The two vertical frame rods of the front frame (110) are provided with connecting pipe cavities (100) at their upper ends. The two vertical handrails (13) of the lifting handrail are inserted into the connecting pipe cavities (100) of the two vertical frame rods of the front frame (110) in a one-to-one correspondence.

10. The ladder of claim 9, wherein, The hinge (9) includes: A cylindrical body (91) is fitted onto the outside of the vertical frame rod of the front frame (110). A slot (911) is provided on one side of the cylindrical body (91) in the circumferential direction, which runs through the circumferential wall of the cylindrical body (91) in both the axial and radial directions. Two clamping plates (92) are fixedly connected to the outer wall of the cylindrical body (91) and located on both sides of the gap (911). Hinges are provided on the clamping plates (92). The vertical frame of the rear frame (120) is clamped between the two clamping plates (92). The fastener passes through the hinge holes provided on the two clamping plates (92) and the junction hole provided on the vertical frame rod of the rear frame (120) to hinge the vertical frame rod of the rear frame (120) to the two clamping plates (92).

Images