Stroller board locking mechanism and foldable stroller ladder

Abstract

This utility model provides a trolley board locking mechanism and a foldable trolley ladder, relating to the field of ladders. The trolley board locking mechanism includes a base, a locking hook, a spring, and a mounting assembly. The locking hook is rotatably mounted on the base about its axial direction. The locking hook has a first end and a second end located on both sides of the base's axial direction, and the first end has a hook portion extending toward the second end of the base. The spring is mounted on the base and connected to the locking hook. The spring is configured to store elastic potential energy when the second end of the locking hook rotates relative to the base under the action of an external force, and to release elastic potential energy to drive the locking hook to rotate relative to the base when the external force is removed. The mounting assembly is used to fix the base to the ladder frame of the foldable trolley ladder where the trolley board is mounted. This trolley board locking mechanism is installed on the foldable trolley ladder. This utility model solves the technical problem in the prior art where the trolley board of a foldable trolley ladder may accidentally open when used as a ladder, posing a safety hazard.

Description

Technical Field

[0001] This utility model relates to the field of ladders, and in particular to a trolley board locking mechanism and a foldable trolley ladder. Background Technology

[0002] In daily life and work scenarios, trolley ladders are widely used because they combine the functions of a ladder and a trolley. For example, in some small logistics warehouses, staff need to use the trolley function of the trolley ladder to move goods, and also use its ladder function to climb up and retrieve goods.

[0003] The main structure of the foldable trolley ladder includes two side ladder frames and a trolley structure—wheels and a trolley board—installed at the lower end of one side ladder frame. The two side ladder frames are opened to use their ladder function, and the two side ladder frames are folded together and the trolley board is opened to use their trolley function.

[0004] However, some problems were found in the use of existing foldable ladders: when using the ladder function, the trolley board that should be closed sometimes opens unexpectedly, which affects the overall stability of the ladder. In some cases, it can even cause the ladder to slide or tip over. This is undoubtedly a huge safety hazard for people working on the ladder, and may cause accidents such as falls and injuries. Utility Model Content

[0005] The purpose of this invention is to provide a trolley board locking mechanism and a foldable trolley ladder to solve the above-mentioned technical problems existing in the prior art.

[0006] To achieve the above objectives, the embodiments of this utility model adopt the following technical solutions:

[0007] In a first aspect, this utility model provides a trolley plate locking mechanism for use in a foldable trolley ladder, the trolley plate locking mechanism comprising:

[0008] The base has an axial direction, with one end of the axial direction being the first end of the base and the other end of the axial direction being the second end of the base.

[0009] A locking hook is rotatably mounted on the base about the axial direction of the base. The locking hook has a first locking hook end and a second locking hook end located on both sides of the axial direction of the base, and the first locking hook end is provided with a hook portion extending toward the second locking hook end of the base.

[0010] A spring is mounted on the base and connected to the locking hook. The spring is configured to store elastic potential energy when the second end of the locking hook rotates relative to the base under the action of an external force, and to release the elastic potential energy to drive the locking hook to rotate relative to the base when the external force is removed.

[0011] Mounting components are used to securely mount the base to the frame of the foldable trolley ladder, which has a trolley board installed.

[0012] In an optional embodiment, the base has an axially penetrating mounting hole inside, and one side of the base in the axial direction has a side groove communicating with the mounting hole.

[0013] A portion of the locking hook is located inside the side groove;

[0014] The mounting assembly includes a mounting shaft and an end locking member. The mounting shaft passes through the mounting hole and through the portion of the locking hook located inside the side groove. The end locking member is threaded onto the portion of the mounting shaft that protrudes from the base.

[0015] In an optional embodiment, the mounting shaft is a bolt, and the end locking element is a nut that matches the bolt.

[0016] In an optional embodiment, the locking hook has an abutment portion on the side surface opposite to the base;

[0017] The spring includes a central retaining ring and spring coils connected to both ends of the central retaining ring; the spring coils are sleeved outside the mounting shaft and their ends away from the central retaining ring are fixedly connected to the base; the central retaining ring is sleeved outside the locking hook and rotates forward in the direction of the locking hook's rotation relative to the base, and the central retaining ring abuts against the rear side of the abutting part.

[0018] In an optional embodiment, a stepped surface is formed on the side of the locking hook away from the base. The portion of the stepped surface near the first end of the locking hook is formed as a higher stepped surface, and the portion near the second end of the locking hook is formed as a lower stepped surface. The abutting portion is formed at the transition connection between the higher stepped surface and the lower stepped surface.

[0019] In an optional embodiment, the hook portion at the first end of the locking hook has anti-slip protrusions on the side surface facing the base.

[0020] In an optional embodiment, the surface of the locking hook near the first end of the locking hook facing the base is an arc-shaped surface that is recessed away from the base.

[0021] And / or, the portion of the locking hook near the second end of the locking hook has a concave arc surface on the side facing the base, which is opposite to the direction of the base.

[0022] In an optional embodiment, the end face of the first end of the base is a curved surface that is recessed toward the second end of the base, so that it can fit against the column surface of the ladder frame on which the trolley board is mounted in the installed state.

[0023] Secondly, this utility model also provides a foldable trolley ladder, including a ladder frame one, a ladder frame two, a step, wheels, and a trolley plate; the upper end of the ladder frame one is hinged to the upper end of the ladder frame two, the wheels are installed at the bottom of the ladder frame one or the ladder frame two, one end of the trolley plate is installed at the bottom of the ladder frame one and the trolley plate can rotate relative to the ladder frame one to open or close towards the side of the ladder frame one away from the ladder frame two; the ladder frame one and the ladder frame two each have two uprights, and the step is hinged between the two uprights of the ladder frame one and the two uprights of the ladder frame two;

[0024] The foldable trolley ladder further includes a trolley board locking mechanism provided in any of the optional embodiments of the first aspect, wherein:

[0025] The base is fixedly installed on one column of the first ladder frame by the mounting assembly. The second end of the base is suspended and extends toward the other column of the first ladder frame. The first end of the locking hook is located on the side of the first ladder frame away from the second ladder frame, and the second end of the locking hook is located on the side of the first ladder frame toward the second ladder frame.

[0026] With the second ladder frame and the first ladder frame open and the trolley plate closed, the hook portion at the first end of the locking hook is hooked onto the edge of the trolley plate away from the bottom of the first ladder frame.

[0027] When the second ladder frame is combined with the first ladder frame, it presses down on the second end of the locking hook. Under the external force of being pressed down by the second ladder frame, the second end of the locking hook rotates relative to the base, so that the hook portion provided at the first end of the locking hook disengages from the trolley plate.

[0028] In an optional embodiment, at the end of the trolley board away from the bottom of the first ladder frame, the side of the trolley board facing away from the second ladder frame is provided with a positioning groove or a positioning flange; when the second ladder frame and the first ladder frame are open and the trolley board is closed, the hook portion provided at the first end of the locking hook is hooked to the positioning groove or the positioning flange.

[0029] And / or, the second ladder frame is provided with a pushing part, and during the process of merging the second ladder frame and the first ladder frame, and in the merged state, the pushing part presses the second end of the locking hook.

[0030] Specifically, in the present invention, the term "and / or" indicates that the structure before "and / or" and the structure after "and / or" are set simultaneously or selectively.

[0031] The embodiments of this utility model can achieve at least the following beneficial effects:

[0032] The trolley locking mechanism provided in this embodiment of the utility model is applied to a foldable trolley ladder, avoiding the risk of the ladder sliding and tipping over due to the trolley opening accidentally when the ladder is used. This improves the safety when using the ladder function. Whether in industrial scenarios such as construction and warehousing logistics, or in daily home use, users do not need to worry about the danger caused by the trolley opening suddenly while working on the ladder. At the same time, when switching from ladder function to trolley function, users do not need to perform complicated unlocking operations manually, saving users' operation time and energy and improving work efficiency.

[0033] For the specific structure and installation method of the embodiments of this utility model, please refer to the detailed description in the Detailed Description of the Embodiments section of this specification. Attached Figure Description

[0034] 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.

[0035] Figure 1 Schematic diagram of the overall structure of the trolley plate locking mechanism provided in this embodiment of the utility model Figure 1 ;

[0036] Figure 2 The trolley plate locking mechanism provided in this embodiment of the utility model is in Figure 1 Schematic diagram of the exploded structure in the state;

[0037] Figure 3 Schematic diagram of the overall structure of the trolley plate locking mechanism provided in this embodiment of the utility model Figure 2 ;

[0038] Figure 4 The trolley plate locking mechanism provided in this embodiment of the utility model is in Figure 3 Schematic diagram of the exploded structure in the state;

[0039] Figure 5 This is a structural schematic diagram of the foldable trolley ladder provided in the embodiment of the present invention with both sides of the ladder frame open.

[0040] Figure 6 for Figure 5 Enlarged view of the local structure of region A in the middle;

[0041] Figure 7 This is a schematic diagram of the structure of the foldable trolley ladder provided in the embodiment of the present invention with the two side ladder frames combined.

[0042] Figure 8 for Figure 7 Enlarged view of the local structure of region B in the middle.

[0043] Icons: 1-Base; 101-First end of base; 102-Second end of base; 11-Mounting hole; 12-Side groove; 2-Locking hook; 201-First end of locking hook; 2011-Higher stepped surface; 202-Second end of locking hook; 2021-Lower stepped surface; 21-Hook part; 211-Anti-slip protrusion; 22-Abutting part; 3-Spring; 31-Center retaining ring; 32-Spring ring; 4-Mounting assembly; 41-Mounting shaft; 42-End locking element;

[0044] 51-Ladder frame one; 52-Ladder frame two; 521-Pushing part; 501-Column; 53-Step; 6-Walking wheel; 7-Trolley board. Detailed Implementation

[0045] 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.

[0046] 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.

[0047] 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.

[0048] In the description of this utility model, it should be noted that 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 utility model product is in use. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element 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 this utility model. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0049] Furthermore, the terms "horizontal" and "vertical" do not imply that the component must be absolutely horizontal or suspended, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0050] In the description of this utility model, it should also be noted that, unless otherwise explicitly 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.

[0051] The following detailed description, in conjunction with the accompanying drawings, outlines some embodiments of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0052] First aspect

[0053] This embodiment provides a trolley plate locking mechanism, referring to... Figures 1 to 4 This trolley plate locking mechanism is applied to a foldable trolley ladder. Specifically, the trolley plate locking mechanism includes a base 1, a locking hook 2, a spring 3, and a mounting assembly 4. The base 1 has an axial direction, with one end being a base first end 101 and the other end being a base second end 102. The locking hook 2 is rotatably mounted on the base 1 about its axial direction. The locking hook 2 has a locking hook first end 201 and a locking hook second end 202 located on both sides of the axial direction of the base 1, and the locking hook first end 201 has a hook portion 21 extending toward the base second end 102. The spring 3 is mounted on the base 1 and connected to the locking hook 2. The spring 3 is configured to store elastic potential energy when the locking hook second end 202 rotates relative to the base 1 under the action of an external force, and to release elastic potential energy to drive the locking hook 2 to rotate relative to the base 1 when the external force is removed. The mounting assembly 4 is used to fix the base 1 to the ladder frame of the foldable trolley ladder on which the trolley plate 7 is mounted.

[0054] To illustrate in more detail the rotation path of the locking hook 2 around the base 1 in the trolley locking mechanism provided in this embodiment, as follows: Figure 1 The diagram defines the front-to-back direction, and the locking hook 2 is mounted on the base 1 and rotates in the front-to-back direction. This trolley plate locking mechanism is in the spring-free state... Figure 1 In the initial state shown, when the second end 202 of the locking hook is subjected to an external force, the second end 202 of the locking hook (locking hook 2) rotates from front to back relative to the base 1. During this process, the spring 3 stores elastic potential energy, and the external force causes the locking hook 2 to rotate relative to the base 1 to... Figure 3As shown in the diagram; when the external force acting on the second end 202 of the locking hook is removed, the spring 3 rebounds and releases its elastic potential energy to drive the locking hook 2 to rotate relative to the base 1 from back to front, as shown in the diagram. Figure 1 The initial state is shown.

[0055] The trolley locking mechanism provided in this embodiment is applied to a foldable trolley ladder.

[0056] Specifically, refer to Figures 5 to 8 The foldable trolley ladder includes a first ladder frame 51, a second ladder frame 52, a step 53, wheels 6, and a trolley plate 7. The upper end of the first ladder frame 51 is hinged to the upper end of the second ladder frame 52. The wheels 6 are installed at the bottom of the first ladder frame 51 or the second ladder frame 52 (for example, as shown in the figure, installed at the bottom of the first ladder frame 51). One end of the trolley plate 7 is installed at the bottom of the first ladder frame 51, and the trolley plate 7 can rotate relative to the first ladder frame 51 to open or close towards the side of the first ladder frame 51 away from the second ladder frame 52. The first ladder frame 51 and the second ladder frame 52 each have two uprights 501. The step 53 is hinged between the two uprights 501 of the first ladder frame 51 and the two uprights 501 of the second ladder frame 52. Among them, either ladder frame 1 51 or ladder frame 2 52 is the main ladder frame, and the other is the secondary ladder frame. When the main ladder frame and the secondary ladder frame are opened, at least one layer of treads 53 (optional, one or more layers, such as three layers as shown in the figure) unfolds between the main ladder frame and the secondary ladder frame for the user to climb.

[0057] Based on this structure, the base 1 of the trolley board locking mechanism provided in this embodiment is fixedly installed on a column 501 of the first ladder frame 51 by the mounting assembly 4. The second end 102 of the base is suspended and extends toward the other column 501 of the first ladder frame 51. The first end 201 of the locking hook is located on the side of the first ladder frame 51 away from the second ladder frame 52, and the second end 202 of the locking hook is located on the side of the first ladder frame 51 toward the second ladder frame 52. When ladder frame 2 52 and ladder frame 1 51 are open and trolley plate 7 is closed (i.e., trolley plate 7 is closed and no external force is applied to the second end 202 of the locking hook), the hook part 21 of the first end 201 of the locking hook is hooked to the side of the trolley plate 7 away from the bottom of ladder frame 1 51; when ladder frame 2 52 is in the closed state with ladder frame 1 51, it presses down on the second end 202 of the locking hook, and the second end 202 of the locking hook rotates relative to the base 1 under the external force of being pressed down by ladder frame 2 52, so that the hook part 21 of the first end 201 of the locking hook is disengaged from the trolley plate 7.

[0058] refer to Figure 1 The forward and backward directions are defined as shown:

[0059] When the trolley function is applied, ladder frame 2 52 and ladder frame 1 51 are combined. During the process, ladder frame 2 52 presses the second end 202 of the locking hook. Under the action of the external force pressed by ladder frame 2 52, the second end 202 of the locking hook rotates from front to back relative to the base 1, so that the hook part 21 provided on the first end 201 of the locking hook is disengaged from the trolley plate 7. During the process, the spring 3 stores elastic potential energy. At this time, the trolley plate 7 can be opened to apply the trolley function.

[0060] When the ladder function is applied, ladder frame 2 52 and ladder frame 1 51 open. No external force acts on the first end 201 of the locking hook. Spring 3 rebounds, releasing elastic potential energy to drive the locking hook 2 to rotate relative to the base 1 from back to front. Figure 1 In the initial state shown, the trolley plate 7 is closed before rotation. When rotated to the position, the hook part 21 of the first end 201 of the locking hook can hook onto the edge of the trolley plate 7 away from the bottom of the ladder frame 51, thereby ensuring that the trolley plate 7 will not be accidentally opened when the ladder function is used.

[0061] The trolley locking mechanism provided in this embodiment avoids the risk of the ladder sliding and tipping over due to the trolley 7 accidentally opening when the user is using the ladder function, thus improving the safety when using the ladder function. Whether in industrial scenarios such as construction and warehousing logistics, or in daily home use scenarios, users do not need to worry about the danger caused by the trolley suddenly opening while working on the ladder. At the same time, when switching from ladder function to trolley function, users do not need to perform complicated unlocking operations manually, saving users' operation time and energy and improving work efficiency.

[0062] It should be noted that this embodiment does not limit the specific material of the locking hook 2. In some optional embodiments, the locking hook 2 is made of metal materials such as alloy steel to obtain high strength and durability, and can withstand the large external force that the trolley board 7 may apply without deformation or damage. In other optional embodiments, the locking hook 2 can also be made of rigid plastics such as reinforced nylon. When reinforced nylon is used, the reinforced nylon material has good strength, wear resistance and light weight. It can also be further improved in mechanical properties by adding fiber reinforcement materials inside through a special injection molding process. The spring 3 is a compression spring with a suitable elastic coefficient.

[0063] In an optional embodiment of this example, the base 1 has an axially penetrating mounting hole 11 inside, and a side groove 12 communicating with the mounting hole 11 is provided on one side of the base 1 along the axial direction; a portion of the locking hook 2 is provided inside the side groove 12; the mounting assembly 4 includes a mounting shaft 41 and an end locking member 42, wherein the mounting shaft 41 passes through the aforementioned mounting hole 11 and through the portion of the locking hook 2 located inside the side groove 12 (the portion of the locking hook 2 located inside the side groove 12 has a through hole extending axially along the base 1, and the mounting shaft 41 passes through the mounting hole 11 and through the through hole); the end locking member 42 is threaded onto the portion of the mounting shaft 41 that protrudes from the base 1. During installation, a laterally extending assembly hole is provided on the ladder frame column 501, the mounting shaft 41 is inserted into the assembly hole, and the end locking member 42 is used to lock the base 1 to one side of the column 501. In some further optional embodiments, the mounting shaft 41 is a bolt, and the end locking member 42 is a nut that matches the bolt. The bolt passes through the mounting hole provided on the column 501 from one side of the column 501, and the base 1 is provided on the other side of the column 501. The nut is threadedly installed on the free end of the column 501 away from the bolt to lock the base 1. In other optional embodiments, the mounting shaft 41 may also be a double-ended stud, and the end locking member 42 includes two sets of nuts, which are threadedly installed on the two end sections of the mounting shaft 41 located on both sides of the column 501.

[0064] In this embodiment, there are various specific installation structures for the spring 3 mounted on the base 1 and connected to the locking hook 2. These include, but are not limited to, a linear spring where one end of the spring 3 is fixedly connected to the base 1 and the other end is fixedly connected to the locking hook 2; or, the spring 3 includes two torsion springs arranged axially along the base 1 on both sides of the locking hook 2, with one end of each torsion spring fixedly connected to the base 1 and the other end fixedly connected to the locking hook 2. These fixed connection methods include, but are not limited to, welding or bonding, or connection using limiting insertion holes on the base 1 and the locking hook 2. In some optional embodiments of this embodiment, the locking hook 2 has an abutment portion 22 on its surface away from the base 1; the spring 3 includes a central retaining ring 31 and spring coils 32 connected to both ends of the central retaining ring 31; the spring coils 32 are sleeved outside the mounting shaft 41, with one end away from the central retaining ring 31 fixedly connected to the base 1; the central retaining ring 31 is sleeved outside the locking hook 2 and rotates forward in the direction of rotation of the locking hook 2 relative to the base 1, with the central retaining ring 31 abutting against the rear side of the abutment portion 22. In this optional embodiment, the installation method of spring 3 is more secure than other optional embodiments, making it less likely to fall off, thus improving the durability of the trolley plate locking mechanism. At the same time, it simplifies the assembly process and makes it easier to manufacture.

[0065] In this optional embodiment, the abutment portion 22 may be a protrusion or groove provided on the side surface of the locking hook 2 facing away from the base 1, or it may be other structures, such as in some optional embodiments of this embodiment. Figures 1 to 4As shown, a stepped surface is formed on the side of the hook 2 facing away from the base 1. In this stepped surface, the part near the first end 201 of the hook is formed into a higher stepped surface 2011, and the part near the second end 202 of the hook is formed into a lower stepped surface 2021. The abutting part 22 is formed at the transition connection between the higher stepped surface 2011 and the lower stepped surface 2021 (that is, the front end surface of the hook 2 facing away from the base 1 is high and the rear end surface is low, and the middle retaining ring 31 abuts at the junction of the front end surface and the rear end surface).

[0066] In addition, in an optional embodiment of this example, the hook portion 21 of the first end 201 of the lock hook has an anti-slip protrusion 211 on the side surface facing the base 1. The anti-slip protrusion 211 can further enhance the locking stability of the trolley plate 7 in the locked state.

[0067] In an optional embodiment of this example, the surface of the locking hook 2 near the first end 201 facing the base 1 is a concave arc surface facing away from the base 1. This arc surface design makes it easier for the hook portion 21 at the second end 202 of the locking hook to hook and detach from the edge of the trolley plate 7 during operation, improving adaptability. And / or, the surface of the locking hook 2 near the second end 202 facing the base 1 is a concave arc surface facing away from the base 1. This arc surface design can be used to avoid the crossbeams and other structures on the uprights 501 of the ladder frame where the trolley plate 7 is installed, without interfering with the design structure of the ladder frame itself. This avoids the problem of weakening the strength of the ladder frame structure due to the reduction of crossbeams and other structures caused by the design of the trolley plate locking mechanism. Here, "and / or" indicates that the structure before "and / or" and the structure after "and / or" are set simultaneously or selectively.

[0068] In an optional embodiment of this example, the end face of the first end 101 of the base is a curved surface that is recessed toward the second end 102 of the base, so that it can fit against the surface of the column 501 of the ladder frame on which the trolley plate 7 is installed in the installed state, thereby improving the stability of the base 1 fixed to the column 501, preventing the base 1 and the locking hook 2 from rotating synchronously, and ensuring the effectiveness of the locking and unlocking functions of the trolley plate locking mechanism.

[0069] Second aspect

[0070] This embodiment also provides a foldable trolley ladder.

[0071] Reference Figures 5 to 8A foldable trolley ladder typically includes a first ladder frame 51, a second ladder frame 52, a step 53, wheels 6, and a trolley plate 7. The upper end of the first ladder frame 51 is hinged to the upper end of the second ladder frame 52. The wheels 6 are installed at the bottom of the first ladder frame 51 or the second ladder frame 52 (for example, as shown in the figure, installed at the bottom of the first ladder frame 51). One end of the trolley plate 7 is installed at the bottom of the first ladder frame 51, and the trolley plate 7 can rotate relative to the first ladder frame 51 to open or close towards the side of the first ladder frame 51 away from the second ladder frame 52. The first ladder frame 51 and the second ladder frame 52 each have two uprights 501. The step 53 is hinged between the two uprights 501 of the first ladder frame 51 and the two uprights 501 of the second ladder frame 52. Among them, either ladder frame 1 51 or ladder frame 2 52 is the main ladder frame, and the other is the secondary ladder frame. When the main ladder frame and the secondary ladder frame are opened, at least one layer of treads 53 (optional, one or more layers, such as three layers as shown in the figure) unfolds between the main ladder frame and the secondary ladder frame for the user to climb.

[0072] Continue to refer to Figures 5 to 8 In addition to the above structure, the foldable trolley ladder provided in this embodiment also includes a trolley plate locking mechanism provided in any optional embodiment of the first aspect.

[0073] Specifically, such as Figure 6 and Figure 8 As shown, the base 1 of the trolley plate locking mechanism is fixedly installed on a column 501 of the first ladder frame 51 by the mounting assembly 4. The second end 102 of the base is suspended and extends toward the other column 501 of the first ladder frame 51. The first end 201 of the locking hook is located on the side of the first ladder frame 51 away from the second ladder frame 52, and the second end 202 of the locking hook is located on the side of the first ladder frame 51 facing the second ladder frame 52. When ladder frame 2 52 and ladder frame 1 51 are open and trolley plate 7 is closed (i.e., trolley plate 7 is closed and no external force is applied to the second end 202 of the locking hook), the hook part 21 of the first end 201 of the locking hook is hooked to the side of the trolley plate 7 away from the bottom of ladder frame 1 51; when ladder frame 2 52 is in the closed state with ladder frame 1 51, it presses down on the second end 202 of the locking hook, and the second end 202 of the locking hook rotates relative to the base 1 under the external force of being pressed down by ladder frame 2 52, so that the hook part 21 of the first end 201 of the locking hook is disengaged from the trolley plate 7.

[0074] Its working principle is described in the relevant section 1.

[0075] Furthermore, in the foldable trolley ladder provided in this embodiment, optionally, at the end of the trolley plate 7 away from the bottom of the ladder frame 51 (i.e., the opposite end of the trolley plate 7 and the bottom hinged end of the ladder frame 51), the side of the trolley plate 7 facing away from the ladder frame 52 is provided with a positioning groove or positioning flange. When the ladder frame 52 and ladder frame 51 are open and the trolley plate 7 is closed (i.e., the trolley plate 7 is closed and no external force is applied to the second end 202 of the locking hook), the hook portion 21 of the first end 201 of the locking hook is hooked onto the aforementioned positioning groove or positioning flange. This structure further enhances the stability of the hook portion 21 of the first end 201 of the locking hook when it is hooked onto the side of the trolley plate 7, further improving the reliability of locking the trolley plate 7.

[0076] In an optional embodiment of this example, a pushing part 521 is provided on the second ladder frame 52. This pushing part 521 can be part of the frame structure of the second ladder frame 52 itself, or it can be a structure separately provided on the upright 501 of the second ladder frame 52. For example, the pushing part 521 can be the upright 501 of the second ladder frame 52 itself (as long as the width of the second ladder frame 52 at the corresponding height of the locking hook 2 when the first ladder frame 51 and the second ladder frame 52 are combined is less than the width of the first ladder frame 51 at the corresponding height of the locking hook 2). Alternatively, the pushing part 521... 21 can also be a protrusion on one column 501 of the second ladder frame 52 protruding towards the other column 501, or the pushing part 521 can be a structure such as a crossbeam between the two columns 501 of the second ladder frame 52; during the process and state of merging the second ladder frame 52 and the first ladder frame 51, the pushing part 521 presses the second end 202 of the locking hook, and the second end 202 of the locking hook rotates relative to the base 1 under the action of the external force pressed by the pushing part 521, so that the hook part 21 provided on the first end 201 of the locking hook is disengaged from the pusher plate 7.

[0077] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to mutually. The above embodiments in this specification are only used to illustrate the technical solutions of this utility model, and not 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 embodiments, or equivalent substitutions can be made to some or all of the technical features. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the various embodiments of this utility model.

Claims

1. A stroller board locking mechanism for use in a foldable stroller, the stroller board locking mechanism comprising: The stroller board locking mechanism comprises: a base (1) having an axial direction, one end of which is a first end (101) of the base and the other end is a second end (102) of the base; a lock hook (2) rotatably mounted on the base (1) along the axial direction of the base (1), the lock hook (2) having a first end (201) and a second end (202) of the lock hook (2) disposed on both sides of the axial direction of the base (1), and the first end (201) of the lock hook (2) being provided with a hooking portion (21) extending towards the second end (102) of the base (1); a spring (3) mounted on the base (1) and connected with the lock hook (2), the spring (3) being configured to store elastic potential energy when the second end (202) of the lock hook (2) is subjected to an external force and to release the elastic potential energy to drive the lock hook (2) to rotate relative to the base (1) when the external force is removed; a mounting assembly (4) for fixedly mounting the base (1) on a stroller frame of a foldable stroller ladder.

2. The stroller board locking mechanism of claim 1, wherein: The base (1) is internally provided with an axial through mounting hole (11), and one side of the base (1) is provided with a side recess (12) in communication with the mounting hole (11); a part of the lock hook (2) is disposed inside the side recess (12); the mounting assembly (4) comprises a mounting shaft (41) and an end locking member (42), the mounting shaft (41) passing through the mounting hole (11) and the part of the lock hook (2) disposed inside the side recess (12); and the end locking member (42) being threadedly mounted on the part of the mounting shaft (41) exposed outside the base (1).

3. The stroller board locking mechanism of claim 2, wherein: The mounting shaft (41) is a bolt, and the end locking member (42) is a nut matched with the bolt.

4. The stroller board locking mechanism of claim 2, wherein: The side surface of the lock hook (2) away from the base (1) is provided with an abutting portion (22); the spring (3) comprises a middle clasp (31) and spring coils (32) connected to both ends of the middle clasp (31); the spring coils (32) are sleeved outside the mounting shaft (41) and are fixedly connected to the base (1) at the end away from the middle clasp (31); and the middle clasp (31) is sleeved outside the lock hook (2) and is rotatable in a direction from back to front when the lock hook (2) rotates relative to the base (1), and the middle clasp (31) abuts against the back side of the abutting portion (22).

5. The stroller board locking mechanism of claim 4, wherein: The side surface of the lock hook (2) away from the base (1) forms a stepped surface, in which the part close to the first end (201) of the lock hook forms a higher stepped surface (2011), and the part close to the second end (202) of the lock hook forms a lower stepped surface (2021), and the abutting portion (22) is formed at the transition connection between the higher stepped surface (2011) and the lower stepped surface (2021).

6. The stroller board locking mechanism of claim 1, wherein: The hooking portion (21) provided on the first end (201) of the lock hook (2) is provided with an anti-slip protrusion (211) on the side surface facing the base (1).

7. The stroller board locking mechanism of claim 1, wherein: The surface of the part of the hook (2) near the first end (201) of the hook facing the base (1) is an arc surface that is concave away from the base (1); And / or, the portion of the locking hook (2) near the second end (202) of the locking hook has a concave arc surface on the side facing the base (1) away from the base (1).

8. The stroller board locking mechanism of claim 1, wherein: The end face of the first end (101) of the base is a curved surface that is recessed toward the second end (102) of the base so that it can fit against the surface of the column (501) of the ladder frame on which the trolley plate (7) is installed in the installed state.

9. A foldable trolley ladder, comprising a first ladder frame (51), a second ladder frame (52), a step (53), wheels (6), and a trolley plate (7); the upper end of the first ladder frame (51) is hinged to the upper end of the second ladder frame (52), the wheels (6) are installed at the bottom of the first ladder frame (51) or the second ladder frame (52), one end of the trolley plate (7) is installed at the bottom of the first ladder frame (51), and the trolley plate (7) is rotatable relative to the first ladder frame (51) to open or close towards the side of the first ladder frame (51) away from the second ladder frame (52); the first ladder frame (51) and the second ladder frame (52) each have two uprights (501), and the step (53) is hinged between the two uprights (501) of the first ladder frame (51) and the two uprights (501) of the second ladder frame (52); characterized in that The foldable trolley ladder further includes a trolley plate locking mechanism as described in any one of claims 1 to 8, wherein: The base (1) is fixedly installed on a column (501) of the first ladder frame (51) by the mounting assembly (4). The second end (102) of the base is suspended and extends toward the other column (501) of the first ladder frame (51). The first end (201) of the locking hook is located on the side of the first ladder frame (51) away from the second ladder frame (52). The second end (202) of the locking hook is located on the side of the first ladder frame (51) facing the second ladder frame (52). When the trolley plate (7) is closed and no external force is applied to the second end (202) of the lock hook, the hook part (21) provided on the first end (201) of the lock hook is hooked to the side of the trolley plate (7) away from the bottom of the ladder frame (51); When the second ladder frame (52) and the first ladder frame (51) are open and the trolley plate (7) is closed, the second end (202) of the lock hook rotates relative to the base (1) under the action of the external force pressed by the second ladder frame (52), so that the hook part (21) provided on the first end (201) of the lock hook is disengaged from the trolley plate (7).

10. The foldable cart ladder of claim 9, wherein: At one end of the trolley plate (7) away from the bottom of the first ladder frame (51), the side of the trolley plate (7) facing away from the second ladder frame (52) is provided with a positioning groove or a positioning flange; when the second ladder frame (52) and the first ladder frame (51) are open and the trolley plate (7) is closed, the hook part (21) provided at the first end (201) of the locking hook is hooked to the positioning groove or the positioning flange; And / or, the second ladder frame (52) is provided with a pushing part (521), and the pushing part (521) presses the second end (202) of the lock hook during the merging process of the second ladder frame (52) and the first ladder frame (51) and in the merging state.

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