A pallet truck and auxiliary wheel assembly thereof

Abstract

The present invention discloses an auxiliary wheel assembly, including an upper bracket, a lower bracket rotatably connected to the upper bracket, and a spring that contacts and abuts against the lower bracket and provides elastic force, and also includes a top rod component connected to the upper bracket and used to contact and abut against the spring to adjust the elastic force of the spring, and an anti-loosening component that cooperates with the top rod component and is used to fit tightly with the outer end surface of the upper bracket to prevent the top rod component from loosening. The present invention also discloses a pallet truck including the above-mentioned auxiliary wheel assembly. The above-mentioned auxiliary wheel assembly can accurately adjust the load borne by the auxiliary wheel as required, thereby reducing the impact of manufacturing errors in the production and assembly process, saving resources and reducing production costs; at the same time, the above-mentioned elastically adjustable auxiliary wheel assembly can be applied to more vehicle models.

Description

Technical Field

[0001] The present invention relates to the technical field of forklift assembly, and in particular to an auxiliary wheel assembly. The present invention also relates to a pallet truck having the auxiliary wheel assembly. Background Art

[0002] A pallet truck is a general term for a type of forklift, including pallet trucks and pallet stackers.

[0003] Currently, if Figure 1 and Figure 2 As shown, the driving system of the pallet truck (including the driving wheel 01) is rigidly connected to the frame 02, while the auxiliary wheels 03 on both sides of the driving wheel 01 are elastically connected to the frame 02, that is, the auxiliary wheels 03 are elastic (usually through springs 04). When designing, the height difference between the auxiliary wheels 03 and the driving wheel 01 is set, so that when the vehicle is on a horizontal road, the spring 04 of the auxiliary wheel 03 has a certain pre-compression amount, and the elasticity of the spring 04 acts on the auxiliary wheel 03, so that the auxiliary wheel 03 helps the driving wheel 01 share a part of the load. Traditional elastic auxiliary wheels, such as Figure 3 As shown, it is composed of a mounting seat 07, an upper bracket 06, a lower bracket 05, a spring 04, and an auxiliary wheel 03, and the relationship between them is that the auxiliary wheel 03 is rotationally connected to the lower bracket 05, and the lower bracket 05 is rotationally connected to the upper bracket 06. At the same time, the lower bracket 05 is in contact with one end surface of the spring 04, and the other end surface of the spring 04 is in contact with the upper bracket 2. In this way, the lower bracket 05 can rotate relative to the upper bracket 06, but at the same time it is affected by the elastic force of the spring 04. In this traditional elastic auxiliary wheel, the load of the auxiliary wheel 03 is converted from the elastic force of the spring 04 and depends on the compression amount of the spring 04. However, the amount of force on the auxiliary wheel 03 is related to the compression of the spring 04, and the compression of the spring 04 is directly determined by the height difference between the driving wheel 01 and the auxiliary wheel 03, and this height difference depends on the respective installation positions of the driving wheel 01 and the auxiliary wheel 03. The driving wheel 01 and the auxiliary wheel 03 are both installed on the frame. Due to manufacturing errors, it is difficult for the installation surfaces of the driving wheel 01 and the auxiliary wheel 03 to meet the precise requirements, which ultimately causes the load distribution of the driving wheel 01 and the auxiliary wheel 03 to fail to reach an ideal state; in addition, the theoretically designed load distribution of the driving wheel 01 and the auxiliary wheel 03 cannot be applied to all working conditions, and once the above-mentioned structure of the driving wheel 01 and the auxiliary wheel 03 is installed, it is impossible to complete the adjustment of the load distribution.

[0004] Therefore, how to avoid the load distribution between the driving wheel and the auxiliary wheel from being unable to be adjusted as needed is a technical problem that those skilled in the art need to solve at present. Summary of the invention

[0005] The purpose of the present invention is to provide an auxiliary wheel assembly, which can accurately increase or decrease the load borne by the auxiliary wheel according to the demand, so as to redistribute the load between the driving wheel and the auxiliary wheel, and at the same time avoid waste caused by manufacturing errors of parts, so as to save costs. Another purpose of the present invention is to provide a pallet truck including the above auxiliary wheel assembly.

[0006] To achieve the above-mentioned purpose, the present invention provides an auxiliary wheel assembly, including an upper bracket, a lower bracket rotatably connected to the upper bracket, and a spring that contacts and abuts against the lower bracket and provides elastic force, and also includes a push rod component connected to the upper bracket and contacts and abuts against the spring to adjust the elastic force of the spring, and an anti-loosening component that is cooperatively connected to the push rod component and is used to tightly fit with the outer end surface of the upper bracket to prevent the push rod component from loosening.

[0007] Preferably, the push rod component is connected to the upper bracket via threads.

[0008] Preferably, the push rod component includes a threaded connection section, and the upper bracket is provided with a threaded hole for cooperating with the threaded connection section.

[0009] Preferably, the anti-loosening component is specifically a nut, and the nut is used to cooperate with the threaded connection section.

[0010] Preferably, the push rod component also includes a first cylindrical section connected to the threaded connection section for contacting and abutting against the end face of the spring, and a second cylindrical section coaxially arranged with the first cylindrical section for inserting into the inner ring of the spring, and the diameter of the second cylindrical section is smaller than the diameter of the first cylindrical section.

[0011] Preferably, it also includes a recessed groove provided on the push rod component for inserting a wrench to rotate the push rod component.

[0012] Preferably, the sink is a hexagonal sink.

[0013] Preferably, the lower bracket includes a guide column for extending into the inner circle of the spring to provide positioning guidance for the spring.

[0014] Preferably, it also includes a mounting seat disposed above the upper bracket and used for being rotatably connected to the upper bracket.

[0015] The present invention further provides a pallet truck, comprising any one of the auxiliary wheel assemblies described above.

[0016] Compared with the above background technology, the present invention designs an auxiliary wheel assembly according to different requirements of pallet trucks. Since the load distribution of the driving wheel and the auxiliary wheel designed theoretically cannot be applied to all working conditions, that is, the load distribution of the driving wheel and the auxiliary wheel cannot be adjusted as needed, it is necessary to use an auxiliary wheel assembly that can accurately adjust the force of the auxiliary wheel on the ground.

[0017] Specifically, the auxiliary wheel assembly includes an upper bracket, a lower bracket and a spring, wherein the lower bracket is rotatably connected to the upper bracket, and the spring is used to provide elastic force to the auxiliary wheel; further, the auxiliary wheel assembly also includes a push rod component and an anti-loosening component, wherein the push rod component is connected to the upper bracket, the push rod component is used to adjust the spring elastic force, the anti-loosening component is cooperatively connected to the push rod component, and the anti-loosening component is tightly fitted with the outer end surface of the upper bracket, thereby preventing the push rod component from loosening, wherein one end surface of the spring is in contact with and abuts against the lower bracket, and the other end surface of the spring is in contact with and abuts against the push rod component, so that the spring can be compressed or anti-loosened by the push rod component, thereby accurately adjusting the force of the auxiliary wheel on the ground, that is, the auxiliary wheel can be adjusted by the push rod component. load, so that the lower bracket can rotate relative to the upper bracket, and the lower bracket is affected by the elastic force of the spring, that is, the lower bracket can swing within the compression stroke corresponding to the spring, and the different elastic forces of the corresponding push rod components are adjusted to the spring, so that the load of the auxiliary wheel on the ground can be adjusted as needed; the above-mentioned setting method can also reduce the impact of manufacturing errors in the production and assembly process, thereby avoiding the scrapping of parts due to large manufacturing errors, thereby saving resources and reducing production costs; at the same time, the above-mentioned elastically adjustable auxiliary wheel assembly can be applied to more vehicle models, even if the initial elastic forces of different vehicle models are theoretically designed with different values, the adjustable characteristics of the assembly can also be applied to various vehicle models, realizing true modular design and improving the three levels. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of the initial installation state of the driving wheel and the auxiliary wheel;

[0020] Figure 2 It is a schematic diagram of the driving wheel and the auxiliary wheel touching the ground;

[0021] Figure 3 It is a schematic diagram of the structure of an elastic auxiliary wheel in the prior art;

[0022] Figure 4 A schematic diagram of the structure of an auxiliary wheel assembly disclosed in an embodiment of the present invention;

[0023] Figure 5 for Figure 4 A schematic diagram of the structure of the middle and upper bracket;

[0024] Figure 6 for Figure 4 Schematic diagram of the structure of the middle push rod component.

[0025] in:

[0026] 1-mounting seat, 2-upper bracket, 21-threaded hole, 3-lower bracket, 31-guide column, 4-auxiliary wheel, 5-spring, 6-top rod component, 61-sinking groove, 62-threaded connection section, 63-first cylindrical section, 64-second cylindrical section, 7-anti-loosening component. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The core of the present invention is to provide an auxiliary wheel assembly, which can accurately increase or decrease the load borne by the auxiliary wheel according to the demand, so as to redistribute the load between the driving wheel and the auxiliary wheel, and avoid the waste caused by the manufacturing error of the parts, so as to save the cost. Another core of the present invention is to provide a pallet truck including the above auxiliary wheel assembly.

[0029] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0030] It should be noted that the directional words such as "above, below, left side, right side" described below are all defined based on the drawings in the specification.

[0031] Please refer to Figure 4 , Figure 5 and Figure 6 , Figure 4 A schematic diagram of the structure of an auxiliary wheel assembly disclosed in an embodiment of the present invention; Figure 5 for Figure 4 A schematic diagram of the structure of the middle and upper bracket; Figure 6 for Figure 4 Schematic diagram of the structure of the middle push rod component.

[0032] The auxiliary wheel assembly provided in the embodiment of the present invention includes an upper bracket 2, a lower bracket 3, an auxiliary wheel 4 and a spring 5, wherein the lower bracket 3 is rotatably connected to the upper bracket 2, and the auxiliary wheel 4 is rotatably connected to the lower bracket 3, and at the same time, the lower bracket 3 is in contact with and abuts against one side end surface of the spring 5, so that the lower bracket 3 can make a rotational motion relative to the upper bracket 2, and the lower bracket 3 is also subjected to the elastic force of the spring 5, that is, the lower bracket 3 can swing within the compression stroke corresponding to the spring 5, and the elastic force of the spring 5 can be converted into the load of the auxiliary wheel 4 on the ground; in addition, according to actual application needs, the above-mentioned spring 5 can be selected as a cylindrical coil spring, and the initial installation state of the cylindrical coil spring is horizontally set, wherein the right end surface of the cylindrical coil spring is in contact with and abuts against the lower bracket 3 to realize the conversion of elastic force.

[0033] In addition, the auxiliary wheel assembly is also provided with a mounting seat 1, which is arranged above the upper bracket 2, and the upper bracket 2 is rotatably connected to the mounting seat 1, and the mounting seat 1 is fixedly connected to the frame of the auxiliary wheel assembly. The upper bracket 2 can rotate 360° within a plane relative to the mounting seat 1.

[0034] Furthermore, the auxiliary wheel assembly also includes a push rod component 6 and an anti-loosening component 7, wherein the push rod component 6 is connected to the upper bracket 2, the push rod component 6 is used to adjust the elastic force of the spring 5, and the anti-loosening component 7 is cooperatively connected with the push rod component 6. While the anti-loosening component 7 is cooperatively connected with the push rod component 6, it is tightly fitted with the outer end surface of the upper bracket 2, thereby preventing the push rod component 6 from loosening.

[0035] In this way, one end face of the spring 5 contacts and abuts against the lower bracket 3 on the right, and the other end face of the spring 5 contacts and abuts against the push rod component 6 on the left. In this way, the push rod component 6 can be used to tighten or prevent the spring 5 from loosening, so that the force of the auxiliary wheel 4 on the ground can be accurately adjusted. In other words, the load of the auxiliary wheel 4 can be adjusted through the push rod component 6, and the different elastic forces of the spring 5 can be adjusted corresponding to the push rod component 6, thereby adjusting the load of the auxiliary wheel 4 on the ground as needed.

[0036] The above-mentioned setting method can also reduce the impact of manufacturing errors in the production and assembly processes, thereby avoiding the scrapping of parts due to large manufacturing errors, thereby saving resources and reducing production costs; at the same time, the above-mentioned elastically adjustable auxiliary wheel assembly can be applied to more vehicle models. Even if the initial elastic force of different vehicle models is theoretically designed to be different, the adjustable characteristics of the assembly can also be applied to various vehicle models, realizing a truly modular design.

[0037] In the embodiment of the present invention, the connection between the top rod component 6 and the upper bracket 2 can be a detachable connection, and the premise is that the top rod component 6 can move relative to the upper bracket 2, so that the top rod component 6 can adjust the elastic force of the spring 5. Preferably, the top rod component 6 and the upper bracket 2 are connected by threads to achieve the above function.

[0038] Specifically, the push rod component 6 includes a threaded connection section 62, and the threaded connection section 62 is set to a preset size. For example, according to actual needs, the length of the threaded connection section 62 is set to L, and L is sufficient to satisfy the elastic force adjustment function of the push rod component 6 for the spring 5. The thread of the threaded connection section 62 is set to an external thread, the major diameter is set to M, and the pitch is set to P; accordingly, a threaded hole 21 is opened at the position where the spring 5 is installed on the upper bracket 2, and the threaded hole 21 is opened in the horizontal direction, that is, the axis of the threaded hole 21 is a horizontal straight line. The threaded hole 21 can be matched and connected with the threaded connection section 62 of the push rod component 6, so that the adjustment function of the push rod component 6 for the elastic force of the spring 5 can be realized.

[0039] On the basis of the above, the anti-loosening component 7 can be specifically set as a nut, which can be matched and connected with the threaded connection section 62 of the push rod component 6. At the same time, the close fit between the nut and the left end face of the upper bracket 2 can play a role in preventing the thread of the push rod component 6 from loosening. The nut is a standard part, and its internal thread specifications are the same as those of the threaded hole 21 of the upper bracket 2, that is, the major diameter is M and the pitch is P.

[0040] Of course, the specifications of the internal thread of the nut, the specifications of the threaded hole 21 of the upper bracket 2, and the external thread of the threaded connection section 62 of the push rod component 6 can be adjusted according to actual needs. This article does not make specific restrictions. The above major diameter M and pitch P are only regarded as general cases.

[0041] More specifically, the push rod component 6 also includes a first cylindrical section 63 and a second cylindrical section 64, wherein the first cylindrical section 63 is connected to the right end of the threaded connection section 62, and the second cylindrical section 64 is connected to the right end of the first cylindrical section 63, and the threaded connection section 62, the first cylindrical section 63 and the second cylindrical section 64 are coaxially arranged, wherein the diameter D of the first cylindrical section 63 is greater than the diameter d of the second cylindrical section 64, the diameter d of the second cylindrical section 64 is less than or equal to the inner ring diameter of the spring 5, and the diameter of the threaded connection section 62 can be set to be between D and d, or greater than D, wherein the right side end face of the first cylindrical section 63 with a larger diameter can contact and abut against the left side end face of the spring 5, that is, the spring 5 is pressed against the right side end face of the first cylindrical section 63, and the second cylindrical section 64 with a smaller diameter can be inserted into the inner ring of the spring 5, thereby playing a positioning and guiding role for the spring 5.

[0042] Furthermore, a guide column 31 is provided on the end surface of the lower bracket 3 that contacts and abuts the spring 5. The function of the guide column 31 is similar to that of the second cylindrical section 64 of the above-mentioned push rod component 6, that is, the guide column 31 can extend into the inner circle of the spring 5, so as to play a positioning and guiding role for the spring 5. In this way, the left end surface of the spring 5 contacts and abuts against the right end surface of the first cylindrical section 63 of the push rod component 6, and the right end surface of the spring 5 contacts and abuts against the lower bracket 3, and the spring 5 can operate stably under the joint action of the second cylindrical section 64 and the guide column 31.

[0043] In order to optimize the above embodiment, the auxiliary wheel assembly also includes a groove 61 provided on the left end surface of the push rod component 6, and the groove 61 is used to insert a wrench, so as to achieve the purpose of rotating the push rod component 6. The shape of the groove 61 can be selected in different ways. For example, according to the general application needs of the market, the groove 61 can be set to a hexagonal groove, and the hexagonal groove can be used in conjunction with an Allen wrench, provided that the specifications of the two match.

[0044] To sum up, the upper bracket 2 of the auxiliary wheel assembly is rotatably connected to the mounting base 1, the lower bracket 3 is rotatably connected to the upper bracket 2, the push rod component 6 is threadedly connected to the upper bracket 2, the left end of the spring 5 contacts the end face of the first cylindrical section 63 of the push rod component 6, the left inner ring of the spring 5 is sleeved on the second cylindrical section 64, the right end of the spring 5 contacts the end face of the lower bracket 3, the right inner ring of the spring 5 is sleeved on the guide column 31 of the lower bracket 3, the nut is threadedly connected to the push rod component 6, and one end face of the nut is tightly fitted with the outer end face of the upper bracket 2, thereby preventing the push rod component 6 from loosening.

[0045] The assembled assembly has the following features: Figure 4 X and Y are the spaces reserved on both sides of the top rod component 6. The force F spring of the spring 5 on the lower bracket 3 is finally transmitted to the force F wheel of the auxiliary wheel 4 on the ground. According to the structural relationship, the two forces have the following relationship:

[0046] F round = I × F bullet,

[0047] Where I is a constant, which is the ratio of the lengths of the two force arms. The specific value is related to the structural size.

[0048] and:

[0049] F = K × δ,

[0050] Where K is the stiffness coefficient of spring 5, δ is the initial pre-compression of spring 5,

[0051] Since in this structure, the position of the push rod component 6 can be adjusted by threaded fit, assuming that the amount of thread adjustment is β, and the number of turns of the push rod component 6 is n, then:

[0052] β=n×P, where P is the thread pitch of the push rod component 6, which has been defined above. Assume that the adjustment direction of the push rod component 6 to compress the spring 5 is the positive direction, that is, when the spring 5 is compressed, β is a positive value, and the adjustment direction of the push rod component 6 to relax the spring 5 is the negative direction, that is, when the spring 5 is released, β is a negative value;

[0053] Thus, in the initial state, F wheel = I × F spring = I × K × δ; after adjusting the top rod component 6, F wheel = I × F spring = I × K × (δ + β) = I × K × (δ + n × P),

[0054] In the above formula, only the number of adjustment turns n of the push rod component 6 is a variable, and the rest are constants. Therefore, the load of the auxiliary wheel assembly can be accurately adjusted by adjusting the push rod component 6 to tighten or prevent the spring 5, and the force of the auxiliary wheel 4 on the ground is adjusted accordingly.

[0055] A pallet truck provided by the present invention includes the auxiliary wheel assembly described in the above specific embodiment; other parts of the pallet truck can refer to the prior art and will not be elaborated in this article.

[0056] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0057] The above is a detailed introduction to the pallet truck and its auxiliary wheel assembly provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. An auxiliary wheel assembly, characterized in that: The invention comprises an upper bracket (2), a lower bracket (3) rotatably connected to the upper bracket (2), and a spring (5) in contact with and against the lower bracket (3) and used to provide elastic force, and also comprises a push rod component (6) connected to the upper bracket (2) and in contact with and against the spring (5) to adjust the elastic force of the spring (5), and an anti-loosening component (7) cooperatively connected to the push rod component (6) and used to fit tightly with the outer end surface of the upper bracket (2) to prevent the push rod component (6) from loosening; The push rod component (6) is connected to the upper bracket (2) via threads; The push rod component (6) comprises a threaded connection section (62), and the upper bracket (2) is provided with a threaded hole (21) for matching and connecting with the threaded connection section (62); The anti-loosening component (7) is specifically a nut, and the nut is used to cooperate with the threaded connection section (62) for connection; The push rod component (6) also includes a first cylindrical section (63) connected to the threaded connection section (62) for contacting and abutting against the end face of the spring (5), and a second cylindrical section (64) coaxially arranged with the first cylindrical section (63) for inserting into the inner ring of the spring (5), wherein the diameter of the second cylindrical section (64) is smaller than the diameter of the first cylindrical section (63), the diameter of the second cylindrical section (64) is smaller than or equal to the diameter of the inner ring of the spring (5), the diameter of the threaded connection section (62) is between the diameter of the first cylindrical section (63) and the diameter of the second cylindrical section (64), or is larger than the diameter of the first cylindrical section (63), the right end face of the first cylindrical section (63) can contact and abut against the left end face of the spring (5), and the second cylindrical section (64) can be inserted into the inner ring of the spring (5) to play a positioning and guiding role for the spring (5); It also includes a sink groove (61) provided on the push rod component (6) for inserting a wrench to rotate the push rod component (6), wherein the sink groove (61) is specifically a hexagonal sink groove; The lower bracket (3) comprises a guide column (31) for extending into the inner ring of the spring (5) to provide positioning guidance for the spring (5); It also includes a mounting seat (1) disposed above the upper bracket (2) and used for being rotatably connected to the upper bracket (2).

2. A pallet truck, characterized in that: Comprising the auxiliary wheel assembly as claimed in claim 1.

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