Load wheel arrangement structure, crawler device and hand truck

Abstract

In the field of hand truck technology, a load wheel arrangement structure, a crawler device, and a hand truck are provided. [Solution] The load wheel arrangement structure includes a plurality of load wheels 1 rotatably connected to a support beam 2, of which a plurality of load wheels are provided on the left side of the support beam, divided into at least two sets, with a fixed interval between every two adjacent sets of load wheels, and a plurality of load wheels are provided on the right side of the support beam, divided into at least two sets, with a fixed interval between every two adjacent sets of load wheels. The load wheel arrangement structure provided by this device improves the overall load capacity and structural stability through a rational structural layout, and makes it easy for dirt to be discharged from both sides of the support beam.

Description

[Technical Field]

[0001] The present invention relates to the technical field of hand trucks, and more particularly to a load wheel arrangement structure, a crawler device, and a hand truck. [Background technology]

[0002] Hand trucks are widely used cargo transportation tools and play an indispensable role in multiple fields, including logistics, warehousing, agriculture, and construction. Traditional hand trucks rely on wheels for support and travel, and this structure provides excellent performance on flat, hard surfaces, allowing for efficient and stable cargo transportation. However, when faced with terrain such as sand, mud, or uneven mountain roads, traditional hand trucks tend to feel powerless, easily get trapped in mud, and shake or overturn on uneven ground, significantly limiting their range of use and transportation efficiency. To solve this problem, engineers have introduced the design concept of crawler devices and applied it to hand trucks. This design significantly improves the adhesion between the hand truck and the ground, allowing it to run stably on soft ground such as sand and mud, and greatly improving its maneuverability and stability on uneven roads.

[0003] In the prior art, an invention patent with publication number CN211223573U and titled "Construction Hand Truck Suitable for Complex Terrain" discloses a hand truck, which uses a crawler device to travel, including crawlers and a number of load-bearing driven wheels, but which still has certain problems: 1) the multiple driven wheels are arranged very close together and the gaps between them are very small, making it difficult to easily discharge foreign matter and dirt; 2) each crawler device only has one row of driven wheels, which means that the load-bearing capacity is relatively weak. In order to improve the load-bearing capacity, the driven wheels need to be designed to be relatively large, which takes up a lot of space and is expensive; and 3) no protective structure is provided for each driven wheel, which means that there is a risk that each driven wheel will come off the crawler from the side. Summary of the Invention [Problem to be solved by the invention]

[0004] To solve the technical problems of the load wheel arrangement structure of the crawler device in the prior art hand truck, which makes it difficult to discharge foreign matter present, is large in volume, is costly, and is structurally unstable, this invention provides a load wheel arrangement structure that improves the overall load capacity and structural stability through a rational structural arrangement, reduces size and costs, and makes it easy for dirt to be discharged from both sides of the support beam. [Means for solving the problem]

[0005] The technical solutions of the present invention are as follows:

[0006] One aspect of the present invention provides a load wheel arrangement, including a plurality of load wheels rotatably connected to a support beam, wherein: A plurality of load wheels are provided on the left side of the support beam, and are divided into at least two sets, with a fixed interval between each pair of adjacent load wheels; A plurality of load wheels are provided on the right side of the support beam, and are divided into at least two sets, with a fixed interval between every two adjacent sets of load wheels.

[0007] Furthermore, the load wheels located on both the left and right sides of the support beam are arranged symmetrically, and every two symmetrical load wheels share a central axis.

[0008] Furthermore, the number of load wheels in each set is the same.

[0009] Another aspect of the present invention provides a crawler device, including the load wheel arrangement structure described above, wherein the crawler device further includes a crawler, and each load wheel is located inside the crawler and is in load contact with the crawler.

[0010] Furthermore, the crawler is formed by joining a plurality of crawler shoes together, and protrusions are formed on both sides of the support beam on the inner surface of each of the crawler shoes, and recessed grooves are formed on the radial outer surface of each of the load wheels to fit into and maintain engagement with the protrusions.

[0011] Furthermore, the plurality of crawler shoes are hingedly connected in sequence from head to tail, and each of the crawler shoes has a first connection hole and a second connection hole at the front and rear, and the first connection hole on the rear crawler shoe and the second connection hole on the front crawler shoe are fitted onto a hinge connection shaft to be hingedly connected.

[0012] Furthermore, the protrusion has a stripe shape along the traveling direction, the cross section of the protrusion is arc-shaped, the cross section of the groove is arc-shaped, the top of the protrusion is tight-fit with the bottom of the groove, the crawler device further includes guide wheels, the guide wheels are arranged symmetrically on both sides of the support beam, trapezoidal grooves are formed on the radial outer surfaces of the guide wheels, and the guide wheels are tight-fit with the protrusions on the crawler shoes via the inclined surfaces of the trapezoidal grooves.

[0013] Furthermore, stopper edges are formed on the left and right edges of each of the crawler shoes, and protrusions are provided on the front side or rear side of each of the crawler shoes.

[0014] A further aspect of the present invention provides a hand truck, comprising at least one crawler device according to any one of the above claims.

[0015] Furthermore, the handcart further includes a pallet, and the pallet is attached to a support beam in the crawler device via a mounting frame, the support beam is an aluminum profile, and mounting grooves that run through from front to back are formed on both the left and right sides of the support beam, the mounting frame is a U-shaped bracket, and the heads of the mounting bolts on both the left and right sides of the U-shaped bracket are positioned in the mounting grooves. [Effects of the Invention]

[0016] After adopting the above technical solutions, the load wheel arrangement structure, crawler device, and hand truck provided by the present invention have the following beneficial effects compared to the prior art. The load wheel arrangement structure provided by the present invention groups the load wheels and provides a certain gap between the groups, making it easy for foreign objects, dirt, etc. to be discharged through the gap. In this embodiment, load wheels are provided on both the left and right sides of the support beam, improving the load capacity, reducing the size of the load wheels, and simultaneously improving the stability of the structure. The crawler device of the present invention improves the support capacity and the ability to prevent wheels from slipping off by fitting the protrusions on the crawler shoes with the grooves on the load wheels. The hand truck of the present invention uses the crawler device, and in addition to the above beneficial effects, it also has the advantage of being easy to install. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic view of the load wheel arrangement structure of the present invention at a left viewing angle; [Figure 2] 1 is a schematic view of the load wheel arrangement structure of the present invention at a right viewing angle; [Figure 3] 1 is a structural schematic diagram of a pair of symmetrical load wheels according to the present invention; [Figure 4] 1 is a schematic diagram of the crawler structure of the present invention; [Figure 5] 2 is a schematic view of the left side of the crawler device of the present invention; FIG. [Figure 6] 2 is a schematic view of the crawler device of the present invention from the right side; FIG. [Figure 7] FIG. 6 is an enlarged view of part I in FIG. 5. [Figure 8] 4 is a schematic view of the engagement between the groove on the load wheel and the protrusion on the crawler shoe of the present invention. [Figure 9] 4 is a schematic view of the trapezoidal groove on the guide wheel and the projection on the crawler shoe of the present invention. [Figure 10] 2 is a schematic diagram of the hinge connection between two adjacent crawler shoes of the present invention; FIG. [Figure 11] 1 is a schematic structural view of a crawler shoe according to the present invention at a first viewing angle. [Figure 12]1 is a schematic view of the structure of the crawler shoe of the present invention at a second viewing angle. [Figure 13] 1 is a schematic diagram of the overall structure of the hand truck of the present invention; [Figure 14] 2 is a structural schematic diagram of the support beam and mounting frame of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0018] The following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is for illustrative purposes only and does not constitute any limitation on the present invention and its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without any creative work are also within the scope of protection of the present invention.

[0019] It should be noted that the terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the exemplary embodiments of the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural, and when used herein, the terms "comprises" and / or "includes" are understood to indicate the presence of features, steps, operations, devices, assemblies, and / or combinations thereof.

[0020] In describing the present invention, it should be understood that the orientations or positional relationships indicated by directional terms, such as "front, back, up, down, left, right," "lateral, longitudinal, vertical, horizontal," and "top, bottom" are generally based on the orientations or positional relationships shown in the drawings, and are intended solely to facilitate the description and simplification of the present invention; unless otherwise stated, these directional terms do not indicate or suggest that the indicated devices or elements have a particular orientation or must be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the scope of protection of the present invention; and the directional terms "inside, outside" refer to the inside or outside of the outline of each member itself.

[0021] For ease of description, spatially relative terms such as "above," "above," "on top of," and "above" may be used herein to describe the spatial relationship of one device or feature to another device or feature as shown in the figures. It should be understood that spatially relative terms are intended to encompass different orientations of use or operation of the device other than the orientation depicted in the figures. For example, if a device in the figures were turned upside down, a device described as "above other devices or structures" or "on other devices or structures" would later be positioned "below other devices or structures" or "beneath other devices or structures." Thus, the exemplary term "above" may encompass two orientations: "above" and "below." The device may be oriented in other different ways (rotated 90 degrees or at other orientations) and the spatially relative descriptions used herein interpreted accordingly.

[0022] It should also be noted that the use of terms such as "first" and "second" to define components is intended to facilitate distinction between corresponding components, and unless otherwise specified, the terms have no special meaning and therefore cannot be understood to limit the scope of protection of the present invention.

[0023] As shown in Figures 1 to 3, this embodiment provides a load wheel arrangement structure that can be used in a handcart crawler device, which includes a plurality of load wheels 1, and these load wheels 1 are all rotatably connected to a support beam 2, for example, via members such as a rotating shaft and a bearing, and the support beam 2 is the main beam used for support, supporting the cargo weight and transmitting the supporting force to the plurality of load wheels 1.

[0024] Furthermore, the load wheels 1 are distributed on both the left and right sides of the support beam 2, and there are multiple load wheels 1 on each side. On the left side of the support beam 2, the multiple load wheels 1 are divided into at least two sets, with a fixed interval 11 between every two adjacent sets of load wheels 1, and on the right side of the support beam 2, the multiple load wheels 1 are also divided into at least two sets, with a fixed interval 11 between every two adjacent sets of load wheels 1.

[0025] In this way, compared with the prior art, the load wheel arrangement structure provided by this embodiment groups the load wheels 1 and sets a certain gap 11 between two adjacent pairs of load wheels, making it easier for foreign matter, dirt, etc. to be expelled from the gap 11. In addition, in this embodiment, load wheels 1 are installed on both the left and right sides of the support beam 2, which improves the load capacity and reduces the size of the load wheels 1, while at the same time improving the stability of the structure.

[0026] Preferably, in this embodiment, the number of load wheels 1 located on both the left and right sides of the support beam 2 are the same and are arranged symmetrically in one-to-one correspondence, so that the load wheels 1 on both sides receive the same supporting force and are more stable. Furthermore, by installing in this manner, every pair of symmetrical load wheels 1 can share a single central axis 12, which facilitates installation and saves costs. Preferably, the number of load wheels 1 in each pair is the same, which further improves stability.

[0027] For example, as shown in Figure 1, nine load wheels 1 are provided on each side of the support beam 2, and these load wheels 1 are arranged symmetrically around the support beam 2, with every pair of symmetrical load wheels 1 sharing a central axis 12. On the left and right sides, the nine load wheels 1 are divided into three sets, with three load wheels 1 per set, with a certain interval 11 between every two adjacent sets of load wheels 1, which is greater than the gap between any two load wheels 1 within a set. Of course, in other embodiments, the total number of load wheels 1, the number of load wheels 1 on each side, the number of sets into which the load wheels 1 on each side are divided, the number of load wheels 1 in each set, whether the load wheels 1 are symmetrical, the specific size of the interval 11, etc. can be set according to actual needs.

[0028] As shown in Figures 4 to 12, this embodiment further provides a crawler device that can be used in a handcart, which includes the load wheel arrangement structure described above, and the crawler device further includes a crawler 3, and each load wheel 1 is located inside the crawler 3 and contacts a part of the crawler 3, transmitting the force received by the load wheel 1 to the crawler 3.

[0029] Preferably, the crawler 3 is formed from a plurality of crawler shoes 31 joined together, and as shown in Figures 7 and 8, a protrusion 311 is formed on the inner surface of each crawler shoe 31, i.e., the surface facing the load wheel 1, and each crawler shoe 31 is provided with two protrusions 311, which are arranged symmetrically around the support beam 2 and fit with the load wheels 1 on both sides of the support beam 2. Furthermore, a groove 13 is formed on the radial outer surface of each load wheel 1, so that when the crawler device is running, the load wheel 1 can always be fitted with the protrusions 311 on the left / right side of at least one crawler shoe 31 through the groove 13 on the top.

[0030] In this way, the groove 13 on the load wheel 1 fits into the protrusion 311 on the crawler shoe 31, increasing the support area and improving the load capacity, and allowing the size of the load wheel 1 to be reduced for the same load capacity, thereby reducing costs. In addition, the protrusion 311 on the crawler shoe 31 acts as a stopper for the groove 13 on the load wheel 1, preventing relative lateral displacement between the load wheel 1 and the crawler 3 and preventing the load wheel 1 from separating from the crawler 3 laterally. Furthermore, by installing the crawler 3 so that it is formed by connecting multiple crawler shoes 31, the formed protrusions 311 are not a continuous whole that imitates the crawler 3, but small protrusions 311 divided into multiple crawler shoes 31. If the crawler 3 is a continuous whole and continuous protrusions that imitate the crawler 3 are used, the crawler 3 and protrusions 311 would have to be made of soft materials such as rubber to ensure running. In this embodiment, however, by installing the crawler 3 so that it is formed by connecting multiple crawler shoes 31, the crawler shoe 31 can be made of hard materials such as metal or plastic, improving strength.

[0031] Preferably, in this embodiment, the multiple crawler shoes 31 are hinged sequentially from head to tail, each crawler shoe 31 having the same structure, each crawler shoe 31 having a first connecting hole 3121 and a second connecting hole 3122 at its front and rear positions, respectively, the first connecting hole 3121 on the rear crawler shoe 31 can be aligned with the center of the second connecting hole 3122 on the front crawler shoe 31, and is fitted with a hinge connecting shaft 3123 and fasteners such as screws and nuts to realize the hinge connection.

[0032] Specifically, a connection block 312 is formed to protrude inside the crawler shoe 31, and the first connection hole 3121 and the second connection hole 3122 are formed at the front and rear positions of the connection block 312, respectively; the front part of the connection block 312, including the first connection hole 3121, protrudes from the main body of the crawler shoe 31, and an escape groove 3124 is formed in the middle of this front part, which escape groove 3124 fits into the rear part of the connection block 312, including the second connection hole 3122; the first connection hole 3121 is formed to penetrate both the left and right protruding parts of the front part of the connection block 312, and the second connection hole 3122 is formed to penetrate the rear part of the connection block 312.

[0033] Furthermore, at least two first hole-side molding grooves 3125 are formed radially outward of each first connecting hole 3121 in the connecting block 312, and as shown in Figures 10 to 12, taking the left-side first connecting hole 3121 as an example, the two first hole-side molding grooves 3125 are located in the upper left and lower right, respectively, and the two first hole-side molding grooves 3125 are arranged closely together, thereby forming the first connecting holes 3121 that penetrate left and right at the groove bottoms of the two first hole-side molding grooves 3125. To ensure effective connection of each crawler shoe 31, there is a high requirement for dimensional accuracy of the crawler shoes 31, and therefore they are preferably manufactured by pressure casting. In this embodiment, the front part of the connection block 312, including the first connection hole 3121, is installed to protrude from the body of the crawler shoe 31, facilitating the hinge connection between each crawler shoe 31. The first hole-side molding groove 3125 can be provided above and below this protruding part, thereby simplifying the mold. Here, the mold design only needs to be opened and closed in the vertical direction, and no sliding mechanism is required.

[0034] Similarly, at least two second hole-side molding grooves 3126 are formed radially outward of the second connection hole 3122 in the connection block 312, and as shown in Figures 10 to 12, a total of three second hole-side molding grooves 3126 are provided, two of which are located at the upper left and upper right, respectively, and the third second hole-side molding groove 3126 is located at the rear, and the three second hole-side molding grooves 3126 are provided closely to each other, thereby forming the second connection hole 3122 that penetrates from left to right at the groove bottoms of the three second hole-side molding grooves 3126. Because the protrusions 311 are present on the left and right sides of the crawler shoe 31, providing the third second hole-side molding groove 3126 at the rear facilitates mold design and processing / manufacturing.

[0035] In this embodiment, as shown in Figures 7 and 8, the protrusions 311 on the crawler shoes 31 are strip-shaped along the traveling direction, and the cross sections of the protrusions 311 are arranged so as to be arc-shaped. Furthermore, the cross sections of the grooves 13 on the load wheels 1 are arranged so as to be arc-shaped. The arc-shaped tops of the protrusions 311 are tightly fitted into the arc-shaped bottoms of the grooves 13, i.e., make close contact with each other, improving the support capacity. There is a certain gap between the arc-shaped left and right sides of the protrusions 311 and the arc-shaped left and right sides of the grooves 13, making steering easier. 1-2, the crawler device of this embodiment further includes guide wheels 4, which are symmetrically arranged on both sides of the support beam 2 and are distributed in two locations, front and rear. As shown in FIG. 9, trapezoidal grooves 41 are formed on the radial outer surfaces of the guide wheels 4, and the guide wheels 4 are tightly fitted, i.e., come into close contact with the arc-shaped side edges of the protrusions 311 on the crawler shoes 31, via the inclined surfaces of the trapezoidal grooves 41. The bottom surfaces of the trapezoidal grooves 41 do not come into contact with the arc-shaped tops of the protrusions 311, making steering easy.

[0036] 10 to 12, in this embodiment, stopper edges 313 are further formed on the left and right edges of each crawler shoe 31, which further stop the load wheel 1 and prevent the load wheel 1 from separating laterally from the crawler 3. In this embodiment, protrusions 314 are further provided symmetrically on the front side of each crawler shoe 31, and two adjacent crawler shoes 31 come into contact via these protrusions 314, which provide gaps on the left and right sides of each protrusion 314 and reduce the possibility of foreign matter being caught between the two adjacent crawler shoes 31. Naturally, the protrusions 314 may also be provided on the rear side of each crawler shoe 31.

[0037] 13-14, this embodiment further provides a hand truck, which includes a pallet 5 and two crawler devices as described above, and the two crawler devices are symmetrically distributed below the pallet 5. In other embodiments, there may be only one crawler device, which is located at a middle position below the pallet 5, or there may be three or more crawler devices, all of which are distributed below the pallet 5.

[0038] Specifically, in this embodiment, the hand truck further includes a handle 7, which is attached to the pallet 5. The left and right lower sides of the pallet 5 are attached to the support beam 2 of each crawler device via two mounting frames 6. The support beam 2 is preferably made of aluminum, such as GY-4080C aluminum, and as shown in FIG. 14 , mounting grooves 21 are formed on both the left and right sides of the support beam 2, penetrating the front-to-rear direction. The mounting frames 6 are U-shaped brackets that are installed in an inverted manner. During installation, the left and right sides of the mounting frame 6 are connected via mounting bolts 61, mounting nuts 62, and support tubes 63, respectively. The heads of the mounting bolts 61 can be positioned in the mounting grooves 21, making it easy to adjust the front-to-rear positions of the mounting frames 6 and pallet 5 relative to the support beam 2, and then lock them in place after adjustment. This installation allows the crawler device to be compatible with pallets 5 and mounting frames 6 of various sizes. For example, even if the size of the pallet 5 changes and the front-to-rear distance between the two mounting frames 6 on the same side changes, installation is easy and does not require additional mounting holes to be drilled in the support beam 2.

[0039] As can be seen from the above, the load wheel arrangement structure, crawler device and hand truck provided in this embodiment have the following advantages: the load wheel arrangement structure improves the overall load capacity and structural stability through a rational structural arrangement, reduces costs, and allows dirt to be easily discharged from both sides of the support beam; the protrusions on the crawler shoes of the crawler device fit together with the grooves on the load wheels, improving the support capacity and wheel-off ability; and the hand truck adopts the crawler device and has the above-mentioned advantages, as well as the added advantage of being easy to install.

[0040] The above description is merely a preferred specific embodiment of the present invention, and the protection scope of the present invention is not limited thereto. Those skilled in the art may make equivalent substitutions or modifications based on the technical solutions of the present invention and the ideas of the invention within the technical scope disclosed in the present invention, and these shall also be included in the protection scope of the present invention. [Explanation of symbols]

[0041] Load wheel 1, spacing 11, central axis 12, groove 13, support beam 2, mounting groove 21, crawler 3, crawler shoe 31, protrusion 311, connection block 312, first connection hole 3121, second connection hole 3122, hinge coupling axis 3123, escape groove 3124, first hole side molding groove 3125, second hole side molding groove 3126, stopper edge 313, protrusion 314, guide wheel 4, trapezoidal groove 41, pallet 5, mounting frame 6, mounting bolt 61, mounting nut 62, support tube 63, handle 7.

Claims

1. A load wheel arrangement comprising a plurality of load wheels (1) rotatably connected to a support beam (2), among which: A plurality of load wheels (1) are provided on the left side of the support beam (2), and are divided into at least two sets, with a fixed interval (11) between each pair of adjacent load wheels (1); A load wheel arrangement structure characterized in that a plurality of load wheels (1) are provided on the right side of the support beam (2), divided into at least two sets, with a certain interval (11) provided between each two adjacent sets of load wheels (1).

2. The load wheel arrangement structure according to claim 1, characterized in that the load wheels (1) located on both the left and right sides of the support beam (2) are arranged symmetrically, and every two symmetrical load wheels (1) share a single central axis (12).

3. 3. The load wheel arrangement according to claim 2, wherein the number of load wheels (1) in each set is the same.

4. A crawler device comprising the load wheel arrangement structure according to any one of claims 1 to 3, characterized in that the crawler device further comprises a crawler (3), and each load wheel (1) is located inside the crawler (3) and is in load contact with the crawler (3).

5. The crawler device according to claim 4, characterized in that the crawler (3) is formed by connecting a plurality of crawler shoes (31) head to tail, and a protrusion (311) is formed on the inner surface of each of the crawler shoes (31) on both sides of the support beam (2), and a groove (13) that fits into and maintains engagement with the protrusion (311) is formed on the radial outer surface of each of the load wheels (1).

6. The crawler device described in claim 5, characterized in that the multiple crawler shoes (31) are hingedly connected in sequence from head to tail, each of the crawler shoes (31) has a first connection hole (3121) and a second connection hole (3122) at the front and rear, and the first connection hole (3121) on the rear crawler shoe (31) and the second connection hole (3122) on the front crawler shoe (31) are fitted with a hinge connection shaft (3123) to be hingedly connected.

7. 6. The crawler device according to claim 5, wherein the protrusion (311) has a stripe shape along the traveling direction, the cross section of the protrusion (311) is arc-shaped, the cross section of the groove (13) is arc-shaped, the top of the protrusion (311) is tight-fitted with the bottom of the groove (13), the crawler device further includes guide wheels (4), the guide wheels (4) are symmetrically installed on both sides of the support beam (2), trapezoidal grooves (41) are formed on the radial outer surfaces of the guide wheels (4), and the guide wheels (4) are tight-fitted with the protrusions (311) on the crawler shoes (31) via the inclined surfaces of the trapezoidal grooves (41).

8. The crawler device according to claim 5, characterized in that stopper edges (313) are further formed on the left and right edges of each of the crawler shoes (31), and protrusions (314) are further provided on the front side of each of the crawler shoes (31) or the rear side of each of the crawler shoes (31).

9. A hand truck comprising at least one crawler device according to claim 4.

10. 10. The handcart of claim 9, further comprising a pallet (5), the pallet (5) being attached to a support beam (2) of the crawler device via a mounting frame (6), the support beam (2) being an aluminum profile, mounting grooves (21) penetrating front to back on both the left and right sides of the support beam (2), the mounting frame (6) being a U-shaped bracket, and heads of mounting bolts (61) on both the left and right sides of the U-shaped bracket being positioned in the mounting grooves (21).

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