Cart with tray

By installing a barrier structure and detachable mounting components on the trolley pallet, the problem of goods shifting and falling off the trolley is solved, achieving stable transport of goods and flexibility of use.

CN223494539UActive Publication Date: 2025-10-31ZHONGSHAN CHANGZHI HARDWARE PROD CO LTD
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Patent Information

Application Number
CN202423264415.8
Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2024-12-28
Publication Date
2025-10-31
Estimated Expiration
2034-12-28

AI Technical Summary

Technical Problem

Existing flatbed trolleys lack sufficient friction when handling large but lightweight goods such as foam products, cardboard boxes, inflatable products, and irregularly shaped plastic parts. This causes the goods to easily shift and fall off the trolley, making them difficult to transport smoothly.

Method used

Design a trolley with a pallet, on which a barrier structure is set to restrict the horizontal movement of goods. The pallet is detachably fixed to the base plate and connected to the base plate by mounting components to ensure that the goods are stable inside the pallet.

Benefits of technology

It effectively prevents goods from falling off the base plate, ensuring smooth delivery. At the same time, the detachable design of the pallet increases its flexibility and adapts to different needs.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model relates to the technical field of carts, in particular to a cart with a tray, which comprises a bottom plate, a plurality of trundles and the tray, the trundles are arranged at the bottom of the bottom plate, and the tray is detachably fixed on the top surface of the bottom plate. A fence structure is arranged on the tray and used for limiting goods in the tray from moving out of the tray in the horizontal direction. The goods can be prevented from falling off from the bottom plate, and smooth conveying of the goods is guaranteed.
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Description

Technical Field

[0001] This utility model relates to the field of trolley technology, and in particular to a trolley with a tray. Background Technology

[0002] Existing flatbed trolleys consist of a base and casters at the bottom. Goods are placed on the base and transported as the trolley moves. However, for larger but lighter items such as foam products, cardboard boxes, inflatable products, and irregularly shaped plastic parts, the friction between these items and the base is low. When the trolley moves, the items are prone to shifting relative to the trolley and falling off the base, making it difficult to transport these items smoothly. Utility Model Content

[0003] This utility model provides a trolley with a tray, which can prevent goods from falling off the bottom plate and ensure the smooth transportation of goods.

[0004] To solve the above problems, the present invention adopts the following technical solution:

[0005] An embodiment of this utility model provides a trolley with a pallet, including a base plate, multiple casters disposed at the bottom of the base plate, and a pallet, wherein the pallet is detachably fixed to the top surface of the base plate; the pallet is provided with a barrier structure, which is used to restrict the goods inside the pallet from moving out of the pallet in the horizontal direction.

[0006] In some embodiments, the bottom of the tray is provided with a mounting member, the tray is placed on a base plate, and the mounting member is detachably connected to the base plate.

[0007] In some embodiments, the mounting member includes a rod and a resilient pin disposed on the side of the rod. The top surface of the base plate is provided with a connecting hole extending to its bottom surface, through which the rod can pass. After the resilient pin passes through the connecting hole, the resilient pin pops outward to restrict the rod from moving upward out of the connecting hole.

[0008] In some embodiments, the enclosure structure includes four baffles located at the four corners of the pallet, and each of the four baffles includes a first enclosure portion extending along the length direction of the pallet and a second enclosure portion extending along the width direction of the pallet.

[0009] In some embodiments, the tray includes a base frame and four support plates fixed at the four corners of the base frame, with the four baffles connected to the outer edges of the four support plates respectively.

[0010] In some embodiments, a handle is also included, the handle comprising a connecting seat and a pull rod, the lower end of the pull rod being connected to the connecting seat, and the connecting seat being detachably connected to the base plate.

[0011] In some embodiments, the top surface of the base plate is provided with a mounting hole extending through to its bottom surface, through which the connecting seat can pass; each of the two opposite sides of the connecting seat is provided with a receiving groove, and each receiving groove is provided with a locking member and an elastic member. The locking members in the two receiving grooves can slide in a direction parallel to each other and close to each other. The locking members can slide to a locked state where they at least partially extend out of the receiving groove and to an unlocked state where they retract into the receiving groove; the elastic member abuts against the locking member, and under the elastic force of the elastic member, the locking member remains locked; the locking member is also connected to a pressing plate, which extends from the bottom surface of the connecting seat and can slide relative to the connecting seat with the locking member; after the connecting seat passes through the mounting hole, if the locking member is in the locked state, the locking member can abut against the bottom surface of the base plate to prevent the connecting seat from disengaging from the mounting hole; if the locking member is in the unlocked state, the connecting seat can be pulled out from the mounting hole.

[0012] In some embodiments, the bottom of the outer ends of the two locking members that are far apart from each other are provided with guide ramps, and the height of the guide ramps gradually increases in the direction in which the two locking members are far apart from each other.

[0013] In some embodiments, a protruding limiting ring is provided at the upper end of the outer peripheral surface of the connector, the limiting ring surrounds the outer peripheral surface of the connector and is located above the receiving groove; after the connector passes through the mounting hole, the limiting ring can abut against the top surface of the base plate.

[0014] In some embodiments, the base plate may be detachably combined with the base plate of another trolley with a tray.

[0015] This utility model has at least the following beneficial effects: The trolley of this utility model includes a pallet, and goods can be placed in the pallet. The barrier structure on the pallet can restrict the goods in the pallet from moving out of the pallet in the horizontal direction, which can prevent the goods from falling off the bottom plate and ensure the smooth transportation of goods. At the same time, the pallet is detachably fixed to the top surface of the bottom plate. The pallet can be fixed to the bottom plate or removed from the bottom plate according to the user's needs, making it more flexible and convenient for the user. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a trolley with a tray according to an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the structure of a tray according to an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of a trolley with a tray according to an embodiment of the present invention after the tray is removed;

[0019] Figure 4This is a schematic diagram of the structure of an elastic pin according to an embodiment of the present invention;

[0020] Figure 5 This is a schematic diagram of the structure of a trolley with a tray according to another embodiment of the present invention;

[0021] Figure 6 This is a schematic diagram of the handle structure according to one embodiment of the present invention;

[0022] Figure 7 for Figure 6 The diagram shows the structure of the handle from another perspective;

[0023] Figure 8 This is a cross-sectional schematic diagram of the connecting seat, locking member, and elastic member according to an embodiment of the present utility model;

[0024] Figure 9 This is an exploded view of the connecting seat, locking member, and elastic member according to one embodiment of the present utility model;

[0025] Figure 10 This is a schematic diagram of the structure of a trolley with a tray in an assembled state according to an embodiment of the present invention;

[0026] Figure 11 This is a bottom view of the base plate according to an embodiment of the present invention.

[0027] The attached figures are labeled as follows:

[0028] Connecting seat 100, receiving groove 101, locking element 110, guiding slope 111, guiding groove 112, elastic element 120, pressing plate 130, guiding post 140, limiting ring 150, cover plate 160, through groove 161.

[0029] Pull rod 200, grip 201;

[0030] Connection hole 301, base plate 310, mounting hole 311, caster 320, combination plug 330, connecting plate 340, connection hole 341;

[0031] Tray 400, mounting part 410, insert rod 411, spring pin 412, pin rod 413, spring piece 414, bottom frame 420, reinforcing rod 421, support plate 430;

[0032] The enclosure structure is 500, the baffle is 510, the first enclosure part is 511, and the second enclosure part is 512. Detailed Implementation

[0033] This invention provides the following description with reference to the accompanying drawings to aid in a comprehensive understanding of the various embodiments of the invention as defined by the claims and their equivalents. The description includes various specific details to aid understanding, but these details should be considered exemplary only. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the various embodiments described herein without departing from the scope and spirit of the invention.

[0034] In the description of this utility model, the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. 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.

[0035] It should be understood that when one element (e.g., the first element) is “connected” to another element (e.g., the second element), the element may be directly connected to the other element, or there may be an intervening element (e.g., the third element) between the element and the other element.

[0036] An embodiment of this utility model provides a trolley with a tray, such as Figure 1-3 As shown, the cart includes a base plate 310, multiple casters 320 mounted on the bottom of the base plate 310, and a pallet 400. The casters 320 are rotatable to reduce friction during movement, facilitating overall cart movement. The casters 320 can be either fixed casters or swivel casters. The pallet 400 is detachably fixed to the top surface of the base plate 310, allowing users to attach or detach it as needed. When the pallet 400 is attached to the base plate 310, goods can be placed inside it. When the pallet 400 is detached from the base plate 310, goods can be placed on it, forming a standard trolley for normal goods handling, offering greater flexibility and allowing users to choose the appropriate method based on their needs.

[0037] Meanwhile, the pallet 400 is equipped with a barrier structure 500, which is used to restrict the goods inside the pallet 400 from moving out of the pallet 400 in the horizontal direction. The goods are less likely to fall out of the pallet 400, which is especially suitable for handling large but light goods. It can prevent these goods from falling off during the handling process and ensure the smooth delivery of goods.

[0038] In some embodiments, a mounting member 410 is provided at the bottom of the pallet 400. The pallet 400 is placed on the base plate 310, and the mounting member 410 is detachably connected to the base plate 310. The detachable connection between the mounting member 410 and the base plate 310 enables the pallet 400 to be detachably fixed on the top surface of the base plate 310. At the same time, since the pallet 400 is placed on the base plate 310, the weight of the pallet 400 and the goods inside it is loaded on the base plate 310. The base plate 310 supports the pallet 400 and the goods inside it, which greatly reduces the stress on the mounting member 410 and can extend the service life of the mounting member 410.

[0039] Furthermore, the mounting component 410 includes a rod 411 and a resilient pin 412 disposed on the side of the rod 411. The resilient pin 412 can elastically extend and retract. The top surface of the base plate 310 is provided with a connecting hole 311 extending to its bottom surface. The connecting hole 311 is adapted to the rod 411, and the rod 411 can pass through the connecting hole 311. During the process of the rod 411 passing through the connecting hole 311, the resilient pin 412 is compressed and retracts inward to prevent the rod 411 from passing through the connecting hole 311. After the resilient pin 412 passes through the connecting hole 311, the resilient pin 412 pops outward. When the rod 411 moves upward, the resilient pin 412 will abut against the bottom surface of the base plate 310 to limit the rod 411 from moving upward out of the connecting hole 311. The resilient pin connection enables a detachable connection between the mounting component 410 and the base plate 310, which is simple in structure and convenient for installation and disassembly.

[0040] like Figure 4 As shown, the elastic pin 412 may include a pin rod 413 and an elastic device connected to the pin rod 413. The elastic device may be a spring sheet 414, a spring, or other elastic device. The elastic device may be disposed inside the inner insertion rod 411, and the side wall of the insertion rod 411 may be provided with a pin hole adapted to the pin rod 413. The elastic device abuts against the insertion rod 411, so that the pin rod 413 can elastically extend and retract along the axial direction of the pin hole.

[0041] In some embodiments, such as Figure 1-3 As shown, the enclosure structure 500 includes four baffles 510, which are located at the four corners of the pallet 400. Each of the four baffles 510 includes a first enclosure portion 511 extending along the length direction of the pallet 400 and a second enclosure portion 512 extending along the width direction of the pallet 400. Thus, the baffles 510 can block the movement of goods in both the length and width directions of the pallet 400 to prevent the goods from falling off.

[0042] Furthermore, the pallet 400 includes a base frame 420 and four support plates 430 respectively fixed at the four corners of the base frame 420. Four baffles 510 are respectively connected to the outer edges of the four support plates 430. The support plates 430 have a larger area, and goods can be placed on the support plates 430 to stably support the goods.

[0043] Furthermore, the base frame 420 can be square-shaped, and a reinforcing rod 421 is provided on the inner side of the base frame 420. Both ends of the reinforcing rod 421 are connected to the base frame 420 to enhance the structural strength of the base frame 420. The mounting component 410 can be fixed to the bottom of the reinforcing rod 421.

[0044] In some embodiments, such as Figure 3-9 As shown, the pallet-equipped trolley in this embodiment also includes a handle for the user to grip, allowing them to pull or push the entire trolley. The handle includes a connecting base 100 and a pull rod 200. The lower end of the pull rod 200 is connected to the connecting base 100, which is detachably connected to the base plate 310. In use, the user can pull the pull rod 200 to move the entire trolley. Because the connecting base 100 is detachably connected to the base plate 310, the user can either fix the handle to the base plate 310 or remove it as needed. The top surface of the base plate 310 without the handle is relatively flat, allowing for the placement of larger items without obstruction. This further enhances the flexibility of use, allowing users to choose the trolley according to their actual needs.

[0045] Furthermore, the top surface of the base plate 310 is provided with mounting holes 311 extending to its bottom surface. The mounting holes 311 are adapted to the connecting seat 100, and the connecting seat 100 can pass through the mounting holes 311. Each of the two opposite sides of the connecting seat 100 is provided with a receiving groove 101. The two receiving grooves 101 can be connected to each other or be independent of each other. Each of the two receiving grooves 101 is provided with a locking member 110 and an elastic member 120. The locking members 110 in both receiving grooves 101 can slide in a direction parallel to each other, thus the locking members 110 in the two receiving grooves 101 can move closer to each other or further away from each other. As the locking member 110 slides relative to the connecting seat 100, the locking member 110 can slide to a locked state where it at least partially extends out of the receiving groove 101 and to an unlocked state where it retracts into the receiving groove 101. When the locking member 110 is in the locked state, since it extends at least partially beyond the receiving groove 101, the protruding part bulges out from the side of the connecting seat 100, thus serving as a limit. When the locking member 110 is in the unlocked state, since it retracts into the receiving groove 101, it no longer serves as a limit.

[0046] One end of the elastic member 120 abuts against the locking member 110, and the other end can abut against the inner wall of the receiving groove 101 or other stops inside the receiving groove 101. The elastic member 120 can apply an elastic force to the locking member 110. Under the elastic force of the elastic member 120, the locking member 110 remains locked, at least partially extending out of the receiving groove 101. After the connecting seat 100 is fixed to the bottom plate 310 of the vehicle body, the force of the elastic member 120 can keep the connecting seat 100 connected to the bottom plate 310. Without external force, the connecting seat 100 is difficult to detach from the bottom plate 310, thus improving the stability of the connection. The locking member 110 is also connected to a pressing plate 130. The pressing plate 130 extends from the bottom surface of the connecting seat 100 and can slide relative to the connecting seat 100 with the locking member 110. Thus, the user can press the pressing plate 130, thereby causing the locking member 110 to slide to switch the state of the locking member 110.

[0047] When installing the handle of this embodiment, the user can press the pressing plate 130, causing the locking member 110 to overcome the force of the elastic member 120 and switch the locking member 110 to the unlocked state, so as not to block the connector 100 from being inserted into the mounting hole. Then, the connector 100 is passed through the mounting hole 311, and then the pressing plate 130 is released. Under the action of the elastic member 120, the locking member 110 remains locked. The outwardly protruding locking member 110 can abut against the bottom surface of the base plate 310 to prevent the connector 100 from disengaging from the mounting hole 311, thereby fixing the handle to the base plate 310 of the vehicle body. When disassembling the handle of this embodiment, the user can press the pressing plate 130, causing the locking member 110 to overcome the force of the elastic member 120 and switch the locking member 110 to the unlocked state. The retracted locking member 110 no longer restricts the connector 100. Then, the connector 100 is pulled out from the mounting hole 311, and the handle can be separated from the vehicle body, completing the disassembly.

[0048] In some embodiments, the bottom of the outer ends of the two locking members 110 that are far apart from each other are provided with guide ramps 111, and the height of the guide ramps 111 gradually increases in the direction in which the two locking members 110 are far apart from each other. During the process of inserting the connecting seat 110 into the mounting hole 311, the side edge of the top opening of the mounting hole 311 abuts against the guide ramps 111. Due to the inclined structure of the guide ramps 111, under the action of the pressing force, the locking member 110 will retract inward, thereby reaching the unlocked state retracted into the receiving groove 101, allowing the user to smoothly pass the connecting seat 110 through the mounting hole 311. Therefore, in this embodiment, when installing the handle, it is not necessary to manually press the pressing plate 130. After being subjected to the pressing force, the locking member 110 can automatically retract to the unlocked state, saving the user the operation of pressing the pressing plate 130, making the installation of the handle more convenient.

[0049] In some embodiments, the locking member 110 is provided with a guide groove 112, the extension direction of the guide groove 112 is parallel to the sliding direction of the locking member 110 relative to the connecting seat 100, and a guide post 140 is provided in the receiving groove 101. The guide post 140 is inserted into the guide groove 112 and can slide in the guide groove 112. The cooperation between the guide post 140 and the guide groove 112 guides the sliding direction of the locking member 110, so that the locking member 110 slides stably along a direction parallel to each other and close to each other, avoiding the problem of being unusable due to the deviation of the sliding direction.

[0050] In some embodiments, a protruding limiting ring 150 is provided at the upper end of the outer peripheral surface of the connecting seat 100. The limiting ring 150 surrounds the outer peripheral surface of the connecting seat 100 and is located above the receiving groove 101. After the connecting seat 110 passes through the mounting hole 311, the limiting ring 150 can abut against the top surface of the base plate 310, restricting the connecting seat 110 from further passing through the mounting hole 311, so that the distance between the locking member 110 in the locked state and the bottom surface of the base plate 310 is not too large.

[0051] Ideally, after the handle is installed in place, the limiting ring 150 and the locking member 110 in the locked state can clamp the base plate 310, and the connecting seat 100 is not easy to wobble relative to the base plate 310, which further improves the stability of the handle installed on the base plate 310.

[0052] In some embodiments, the receiving groove 101 forms an opening on the bottom surface of the connecting seat 100, through which the locking member 110 and the elastic member 120 can be installed into the receiving groove 101 to facilitate the assembly of the locking member 110 and the elastic member 120. A cover plate 160 is fixed to the bottom of the connecting seat 100, which covers the opening of the receiving groove 101 on the bottom surface of the connecting seat 100. This can isolate and protect the locking member 110 and the elastic member 120, and can also reduce the entry of dust and other impurities into the receiving groove 101. Meanwhile, the cover plate 160 is provided with a through groove 161. The extension direction of the through groove 161 is parallel to the sliding direction of the locking member 110 relative to the connecting seat 100. The pressing plate 130 extends out of the through groove 161 to extend beyond the connecting seat 100, so that the user can operate the pressing plate 130 from the outside. The existence of the through groove 161 provides space for the pressing plate 130 to slide with the locking member 110. Moreover, the through groove 161 can also guide the movement of the pressing plate 130 to prevent its movement direction from deviating.

[0053] Furthermore, the cover plate 160 can be fixed to the bottom of the connector 100 by various methods such as screw fixing, snap-fit ​​connection or adhesive fixing.

[0054] In some embodiments, the lower end of the pull rod 200 is rotatably connected to the connecting seat 100, allowing the user to rotate the pull rod 200 to the corresponding angle as needed, making it more flexible and convenient to use.

[0055] Of course, the pull rod 200 can also be fixedly connected to the connecting seat 100 and form a preset angle relative to the horizontal direction. In this case, the pull rod 200 cannot be adjusted relative to the connecting seat 100, and the user can pull the pull rod 200 at a specific angle.

[0056] In some embodiments, the pull rod 200 is telescopic to adjust its length to meet the needs of different users or different usage scenarios. Since the telescopic structure of the pull rod is a conventional technical means, its specific implementation will not be described in detail here.

[0057] In some embodiments, the elastic element 120 may be a spring, and the locking element 110 may be provided with a groove in which the spring is located, restricting the movement of the spring so that it can stably provide elastic force. One end of the spring may abut against the inner wall of the groove, and the other end may abut against the inner wall of the receiving groove 101 or other stops inside the receiving groove 101.

[0058] In some embodiments, the upper end of the lever 200 is provided with a grip portion 201 for the user to hold. The grip portion 201 can be bent into a "7"-shaped structure, making it easier for the user to grip and requiring less effort when pulling. A rubber sleeve may be fitted onto the grip portion 201 to increase the user's grip comfort.

[0059] In some embodiments, mounting holes 311 can be provided on all four sides of the base plate 310, and the connecting seat 100 can be fixed in any one of the mounting holes 311. Users can pull the vehicle body from any direction of the base plate 310, making it more flexible to use.

[0060] In some embodiments, such as 10 and Figure 1 As shown, the base plate 310 can be detachably combined with the base plate 310 of another trolley with a tray. The base plates 310 of multiple trolleys can be fixed together, allowing multiple trolleys to be pushed simultaneously. After the base plates 310 of the two trolleys are separated, two independent trolleys are formed, and the user can use the two trolleys independently.

[0061] Furthermore, the base plate 310 is provided with a combination structure and a connection structure that are compatible with each other. The combination structure on the base plate 310 can be connected to the connection structure of another trolley to combine and connect the two trolleys together.

[0062] Furthermore, the assembly structure includes assembly inserts 330 located at the side edges of one long side and one short side of the bottom surface of the base plate 310; the connecting structure includes a connecting plate 340 located at the side edges of the other long side and the other short side of the base plate 310, with a through connecting hole 341 on the top surface of the connecting plate 340. The assembly insert 330 of one of the two trolleys can be inserted into the connecting hole 341 of the other trolley to connect the two trolleys together.

[0063] Specifically, the combination insert 330 at the side edge of the long side of the base plate 310 of one trolley can be inserted into the connecting hole 341 at the side edge of the long side of the base plate 310 of the other trolley, so that the long sides of the base plates 310 of the two trolleys are connected together. The combination insert 330 at the side edge of the short side of the base plate 310 of one trolley can be inserted into the connecting hole 341 at the side edge of the short side of the base plate 310 of the other trolley, so that the short sides of the base plates 310 of the two trolleys are connected together.

[0064] In the above embodiments, the long side refers to the side extending along the length direction, and the short side refers to the side extending along the width direction.

[0065] The terms and words used in the foregoing description and claims are not limited to their literal meaning, but are merely used by the applicant to enable a clear and consistent understanding of the present invention. Therefore, those skilled in the art should understand that the foregoing description of various embodiments of the present invention is for illustrative purposes only, and not intended to limit the present invention as defined by the appended claims and their equivalents.

Claims

1. A trolley with a tray, characterized in that: It includes a base plate, multiple casters located at the bottom of the base plate, and a pallet, the pallet being detachably fixed to the top surface of the base plate; the pallet is provided with a barrier structure, the barrier structure being used to restrict the horizontal movement of goods inside the pallet out of the pallet.

2. The trolley with a tray according to claim 1, characterized in that: The bottom of the tray is provided with a mounting component, the tray is placed on the base plate, and the mounting component is detachably connected to the base plate.

3. The trolley with a tray according to claim 2, characterized in that: The mounting component includes a plug rod and a resilient pin disposed on the side of the plug rod. The top surface of the base plate is provided with a connecting hole extending through to its bottom surface, through which the plug rod can pass. After the resilient pin passes through the connecting hole, the resilient pin pops outward to restrict the plug rod from moving upward out of the connecting hole.

4. The trolley with a tray according to claim 1, characterized in that: The enclosure structure includes four baffles, which are located at the four corners of the pallet. Each of the four baffles includes a first enclosure portion extending along the length of the pallet and a second enclosure portion extending along the width of the pallet.

5. The trolley with a tray according to claim 4, characterized in that: The tray includes a base frame and four support plates fixed at the four corners of the base frame, with the four baffles connected to the outer edges of the four support plates respectively.

6. The trolley with a tray according to any one of claims 1-5, characterized in that: It also includes a handle, which includes a connecting seat and a pull rod. The lower end of the pull rod is connected to the connecting seat, and the connecting seat is detachably connected to the base plate.

7. The trolley with a tray according to claim 6, characterized in that: The top surface of each base plate is provided with a mounting hole extending to its bottom surface, through which the connecting seat can pass. Each of the two opposite sides of the connecting seat is provided with a receiving groove, and each receiving groove contains a locking element and an elastic element. The locking elements in both receiving grooves can slide parallel to each other in a direction of approach. The locking elements can slide to a locked state where at least part of them extend out of the receiving groove, and to an unlocked state where they retract into the receiving groove. The elastic element abuts against the locking element, and under the elastic force of the elastic element, the locking element remains locked. The locking element is also connected to a pressing plate, which extends from the bottom surface of the connecting seat and can slide relative to the connecting seat with the locking element. After the connecting seat passes through the mounting hole, if the locking element is in the locked state, it abuts against the bottom surface of the base plate to prevent the connecting seat from disengaging from the mounting hole; if the locking element is in the unlocked state, the connecting seat can be pulled out of the mounting hole.

8. The trolley with a tray according to claim 7, characterized in that: The bottom of the outer ends of the two locking members, which are far apart from each other, are provided with guide ramps, and the height of the guide ramps gradually increases in the direction in which the two locking members are far apart from each other.

9. The trolley with a tray according to claim 7, characterized in that: A protruding limiting ring is provided at the upper end of the outer peripheral surface of the connecting seat. The limiting ring surrounds the outer peripheral surface of the connecting seat and is located above the receiving groove. After the connecting seat passes through the mounting hole, the limiting ring can abut against the top surface of the base plate.

10. The trolley with a tray according to any one of claims 1-5, characterized in that: The base plate can be detachably combined with the base plate of another trolley with a tray.