A wheel track adjusting mechanism for a trolley and a trolley

Abstract

The utility model relates to the technical field of material handling equipment, and specifically discloses a carrying trolley wheel track adjusting mechanism and carrying trolley, including lifting unit, adjusting unit, lifting unit is fixed in the car body front end, is used for when adjusting and is in contact with ground, the car body front end is lifted and makes the front wheel off the ground, adjusting unit is installed in the car body front side and is connected with the front wheel, drives its transverse movement to change the wheel track after the front wheel off the ground, through the coordinated operation of lifting and adjusting, the flexible, accurate, loadless adjustment of front wheel wheel track is realized, makes the same carrying trolley can switch between the narrow wheel track and wide wheel track mode according to the passage width or load condition, and the adaptability and operation safety of equipment are improved obviously.

Description

Technical Field

[0001] This utility model relates to the technical field of material handling equipment, and specifically to a wheel track adjustment mechanism and a handling vehicle. Background Technology

[0002] Handling vehicles (such as forklifts and pallet trucks) are common equipment used for short-distance transfer of goods in factories, warehouses, ports and other places. Traditional handling vehicles usually have one drive wheel (rear wheel) located at the rear of the vehicle body and two front wheels located near the forks at the front of the vehicle body. The front wheels are the main support points. Currently, the track width of the front wheels of most handling vehicles is fixed.

[0003] This fixed wheelbase design has obvious drawbacks in practical use: if the front wheelbase is designed to be wider, the lateral stability of the pallet truck is better, and its load-bearing capacity and anti-tipping ability are stronger. However, when it needs to pass through narrow aisles, shelf gaps, or door frames, it may be unable to pass due to the excessively wide wheelbase, thus limiting its application scenarios. Conversely, if the front wheelbase is designed to be narrower, the pallet truck's passability is improved, and it can adapt to more complex working environments. However, its stability will decrease accordingly, and there is a greater risk of tipping over when moving heavy goods or making high-speed turns, resulting in prominent safety hazards. Utility Model Content

[0004] This utility model addresses the aforementioned problems. Its purpose is to provide a wheel track adjustment mechanism and a transport vehicle that can flexibly adjust the front wheel track when needed, thereby improving stability in wide passage environments and enhancing passability in narrow passage environments.

[0005] To achieve the above objectives, this utility model provides a wheel track adjustment mechanism for a transport vehicle. The transport vehicle includes a vehicle body and a drive wheel assembly mounted on the bottom of the vehicle body. The drive wheel assembly includes a rear wheel mounted on the rear end of the vehicle body and two front wheels mounted on both sides of the front end of the vehicle body. The wheel track adjustment mechanism includes:

[0006] A lifting unit is fixed to the front end of the vehicle body. The lifting unit has a movable end that can extend relative to the vehicle body and abut against the ground. The movable end is used to lift the front end of the vehicle body in the extended state so that the two front wheels are lifted off the ground.

[0007] An adjustment unit is installed on the front side of the vehicle body and connected to the front wheel;

[0008] When the front end of the vehicle body is in a raised state, the adjustment unit can drive one or two of the front wheels to move toward or away from the side of the vehicle body.

[0009] According to the above-described wheel track adjustment mechanism for transport vehicles, there are two lifting units, which are symmetrically arranged on both sides of the front end of the vehicle body and are used to jointly lift the front end of the vehicle body.

[0010] According to the above-described wheel track adjustment mechanism for transport vehicles, the lifting unit includes a lifting power component and a lifting arm. The lifting power component is fixed to the vehicle body, and one end of the lifting arm is located at the bottom of the vehicle body, while the other end can pass through the vehicle body and connect with the lifting power component.

[0011] According to the above-described wheel track adjustment mechanism for transport vehicles, the lifting power component is a lifting cylinder, which is arranged vertically on the vehicle body, and the piston rod at the bottom of the lifting cylinder is connected to the lifting arm.

[0012] According to the above-described wheel track adjustment mechanism for transport vehicles, two adjustment units are provided, which are respectively located on both sides of the vehicle body and are used to independently drive the two front wheels.

[0013] According to the above-described wheel track adjustment mechanism for transport vehicles, the adjustment unit includes an adjustment power component, which is arranged laterally on the vehicle body. A first rotating shaft is provided on the inner side of the front wheel, and the output end of the adjustment power component is connected to the first rotating shaft.

[0014] According to the above-described wheel spacing adjustment mechanism for transport vehicles, the adjustment power component is a linear motor, and the output shaft of the linear motor is connected to the first rotating shaft.

[0015] According to the above-described wheel track adjustment mechanism for transport vehicles, the adjustment unit further includes a coupling, which is located at the output shaft of the linear motor and connected to the first rotating shaft.

[0016] The wheel track adjustment mechanism for a transporter described above also includes a control unit, which is electrically connected to the lifting unit and the adjustment unit.

[0017] A transport vehicle, comprising:

[0018] The wheel track adjustment mechanism as described above.

[0019] This utility model has the following beneficial effects:

[0020] 1. The adjustable unit enables flexible and adjustable front wheel track of the transport vehicle. Users can adjust the front wheel track at any time according to the actual aisle width or operational stability requirements, significantly improving the adaptability of the transport vehicle to different working environments;

[0021] 2. When adjustment is needed, first use the lifting unit to lift the front of the vehicle body so that the front wheels are off the ground, and then use the adjustment unit to adjust the front wheel track. This avoids the frictional resistance between the front wheels and the ground, making the adjustment process easier and reducing front wheel wear.

[0022] 3. The symmetrical arrangement of the double lifting units and the independently driven double adjustment units ensures smooth vehicle body lifting, flexible and controllable wheel track adjustment, and overall stable and reliable mechanism. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the wheelbase adjustment mechanism and the assembly of the front wheel and the vehicle body in an embodiment.

[0024] Figure 2 This is a schematic diagram of the wheel track adjustment mechanism and the front wheel assembly in an embodiment;

[0025] Figure 3 This is a schematic diagram of the overall structure of the transport vehicle in the embodiment.

[0026] In the picture:

[0027] 100. Lifting unit; 110. Lifting cylinder; 120. Lifting arm;

[0028] 200. Adjustment unit; 210. Linear motor; 220. Coupling;

[0029] 300. Vehicle body;

[0030] 400, front wheel; 410, first axle. Detailed Implementation

[0031] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0032] like Figure 1-3As shown, a pallet truck includes a body 300, a drive wheel assembly mounted on the bottom of the body 300, and a track width adjustment mechanism mounted on the body 300. The drive wheel assembly includes a rear wheel mounted at the rear end of the body 300 and two front wheels 400 mounted on both sides of the front end of the body 300. Since the forks are also usually mounted on the front side of the body 300, the two front wheels 400 are the main support points of the pallet truck, and their track width determines the stability of the pallet truck, especially when the forks pick up heavy objects and the lateral displacement distance is large. The narrow wheelbase of the front wheels 400 increases the risk of tipping over. However, a wide wheelbase between the two front wheels 400 results in poor maneuverability, making it difficult to pass through narrow passages. Therefore, in this embodiment, a wheelbase adjustment mechanism is provided. This mechanism allows for real-time adjustment of the wheelbase between the two front wheels 400. In cases of tipping risk, a wider wheelbase can be used to improve the stability of the transport vehicle. In cases of good stability, a narrower wheelbase can be used to improve the maneuverability of the transport vehicle.

[0033] The wheelbase adjustment mechanism includes a lifting unit 100 and an adjustment unit 200. The lifting unit 100 is fixed to the front end of the vehicle body 300 and has a movable end that can extend relative to the vehicle body 300 and abut against the ground. The movable end is used to lift the front end of the vehicle body 300 in the extended state so that the two front wheels 400 are off the ground. The adjustment unit 200 is installed on the front side of the vehicle body 300 and connected to the front wheels 400. In this embodiment, the core function of the lifting unit 100 is to temporarily relieve the load of the vehicle body 300 borne by the front wheels 400, creating a "zero-pressure, low-friction" physical environment for subsequent wheelbase adjustment. By extending downward through its movable end, it forms a stable support with the solid ground, thereby lifting the front end of the vehicle body 300 along with the forks and any possible load. The direct result of this action is... The lifting unit 100 completely lifts the two front wheels 400, which bear the main support function, off the ground. Under the ideal conditions created by the lifting unit 100, it drives the front wheels 400 to move laterally in a straight line in the horizontal plane, thereby changing the wheel track between the two wheels. Therefore, the lifting unit 100 must work first, and then the adjusting unit 200 works. That is, when the front end of the vehicle body 300 is in a lifted state, the adjusting unit 200 can drive one or two front wheels 400 to move towards or away from the side of the vehicle body 300. The lifting unit 100 is responsible for the vertical displacement to release the constraint of the static friction between the front wheels 400 and the ground, and the adjusting unit 200 is responsible for the horizontal displacement to change the wheel track between the two front wheels 400. The two work together in terms of mechanical structure and control logic to complete a function that a single unit cannot achieve independently.

[0034] In this embodiment, there are two ways to adjust the wheel track: one is to adjust one front wheel 400 individually, so that it moves closer to or further away from the other front wheel 400 to achieve wheel track adjustment; the other is to adjust both front wheels 400 simultaneously, so that they move closer to or further away from each other to achieve wheel track adjustment.

[0035] Furthermore, in this embodiment, since the lifting is done before adjustment, after the front wheel 400 leaves the ground, the adjustment unit 200 only needs to overcome the wheel's own inertia and the slight friction between it and the vehicle body 300. The required driving force is small, and the energy consumption is low. This completely eliminates the problem of severe tire wear and ground scratches caused by the front wheel 400 sliding and dragging on the ground. Both the lifting and adjustment actions are carried out under controlled and low load conditions, resulting in a low failure rate of the mechanism. The lifting unit 100 itself can serve as an emergency support device, increasing the safety of vehicle maintenance.

[0036] Furthermore, two lifting units 100 are provided, symmetrically arranged on both sides of the front end of the vehicle body 300, and used to jointly lift the front end of the vehicle body 300. When the forks are loaded with heavy loads, the front end of the vehicle body 300 has a very large weight. Single-point lifting requires the lifting unit 100 to have a very large force, and single-point lifting will generate a huge concentrated load at the support point. Moreover, the structure of the vehicle body 300 needs to resist the torsional moment generated by this, which may cause structural deformation in the long term. The symmetrical double lifting units 100 are like... The two ends of the carrying pole exert force simultaneously, and the supporting force is distributed on both sides of the vehicle body 300. The force flow path is short and symmetrical, and the lifting force acts directly on the main load-bearing structures on both sides of the vehicle body 300. This greatly eliminates the internal torque of the vehicle body 300, so that the vehicle body 300 always maintains pure translation during the lifting process, avoiding structural torsional stress. Moreover, the two symmetrical support points form a stable support surface, which can effectively resist any lateral disturbance (such as slight uneven ground, personnel contact or gusts of wind), and prevent the vehicle from lateral swaying or overturning during the lifting process.

[0037] Furthermore, the lifting unit 100 includes a lifting power component and a lifting arm 120. The lifting power component is fixed to the vehicle body 300. One end of the lifting arm 120 is located at the bottom of the vehicle body 300, and the other end can pass through the vehicle body 300 and connect with the lifting power component. Since the lifting power component is fixed to the vehicle body 300, it becomes a stable force application base. During the process of the lifting power component driving the lifting arm 120 to extend downward, the lifting arm 120 can move to contact the ground. After contact, if the lifting arm 120 continues to extend downward, the lifting power component will be subjected to a reaction force and rise, thereby driving the front end of the vehicle body 300 to rise synchronously, realizing the lifting action of the front end of the vehicle body 300.

[0038] Furthermore, the lifting cylinder 110 is arranged vertically on the vehicle body 300, and the piston rod at the bottom of the lifting cylinder 110 is connected to the lifting arm 120. Compared with the motor and the air cylinder, the cylinder can provide a much greater thrust than them and the two under the same size, which is the prerequisite for overcoming the weight of the vehicle body 300 and the load.

[0039] Furthermore, there are two adjustment units 200, which are respectively located on both sides of the vehicle body 300 and are used to independently drive the two front wheels 400. The two adjustment units 200 are completely independent, which means that the movement of the left and right front wheels 400 can be controlled separately. This not only enables the synchronous movement of the two wheels in opposite directions, but also enables the independent movement of a single wheel. For example, when it is necessary to pass through an asymmetrical narrow space, only one side of the wheel can be moved, leaving more room for the other side. Compared with the solution of using a single central drive unit (such as a motor with a complex linkage and screw mechanism) to drive the two wheels at the same time, the independent drive solution completely eliminates the mechanical coupling between the movement of the two front wheels 400. The movement of one front wheel 400 will not produce any forced, difficult-to-control linkage or interference to the other front wheel 400 through mechanical linkage, so that the positioning control of each front wheel 400 is independent, precise and without mutual influence.

[0040] Furthermore, the adjustment unit 200 includes an adjustment power component, which is arranged laterally on the vehicle body 300. A first rotating shaft 410 is provided on the inner side of the front wheel 400. The output end of the adjustment power component is connected to the first rotating shaft 410. By arranging the adjustment power component laterally, the direction of movement of its output shaft is completely collinear with the direction in which the wheel needs to move. This means that the linear thrust or pull generated by the adjustment power component can be used 100% to drive the lateral movement of the front wheel 400 without any directional conversion, achieving the highest mechanical transmission efficiency and the most immediate dynamic response.

[0041] In this embodiment, the adjusting power component is a linear motor 210. The output shaft of the linear motor 210 is connected to the first rotating shaft 410. The motor has high control precision and can improve the adjustment precision of the 400mm wheel track of the two front wheels.

[0042] Furthermore, the adjustment unit 200 also includes a coupling 220, which is located between the output shaft of the linear motor 210 and the first rotating shaft 410. The function of the coupling 220 is to allow the first rotating shaft 410 to rotate relative to the output shaft of the linear motor 210, while the output shaft of the linear motor 210 can drive the first rotating shaft 410 to move laterally.

[0043] Furthermore, it also includes a control unit, which is electrically connected to the lifting unit 100 and the adjusting unit 200. Without the control unit, the operator needs to manually, step by step, and in the correct sequence to start the lifting, adjusting, and lowering actions, which is cumbersome and prone to errors. The control unit integrates multiple mechanical actions into a coherent automatic process through a preset program. The user only needs to issue a command (such as pressing the "narrow passage mode" button), and the system will automatically execute the entire process of "lifting the front wheel 400 → adjusting the wheel track to the preset value → lowering the front wheel 400", which greatly simplifies the operation and improves efficiency.

[0044] Of course, this control unit can be the control system of the transport vehicle, or it can be independent of the control system of the transport vehicle.

[0045] The technical solution of this utility model has been described in detail above with reference to the accompanying drawings. The described embodiments are used to help understand the concept of this utility model. The specific embodiments described herein are merely illustrative examples of the spirit of this utility model. Those skilled in the art to which this utility model pertains can make various modifications or additions to the described specific embodiments or use similar methods to replace them, but without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

[0046] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0047] Furthermore, in this utility model, the use of terms such as "first," "second," and "a" is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0048] In this utility model, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0049] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

Claims

1. A wheelbase adjustment mechanism for a transport vehicle, the transport vehicle comprising a vehicle body and a drive wheel assembly mounted on the bottom of the vehicle body, the drive wheel assembly comprising a rear wheel mounted on the rear end of the vehicle body and two front wheels mounted on both sides of the front end of the vehicle body, characterized in that, The wheel track adjustment mechanism includes: A lifting unit is fixed to the front end of the vehicle body. The lifting unit has a movable end that can extend relative to the vehicle body and abut against the ground. The movable end is used to lift the front end of the vehicle body in the extended state so that the two front wheels are lifted off the ground. An adjustment unit is installed on the front side of the vehicle body and connected to the front wheel; When the front end of the vehicle body is in a raised state, the adjustment unit can drive one or two of the front wheels to move toward or away from the side of the vehicle body.

2. The wheel spacing adjustment mechanism for a transport vehicle according to claim 1, characterized in that, The lifting unit is provided in two parts, which are symmetrically arranged on both sides of the front end of the vehicle body and are used to lift the front end of the vehicle body together.

3. A wheel spacing adjustment mechanism for a transport vehicle according to claim 1 or 2, characterized in that, The lifting unit includes a lifting power component and a lifting arm. The lifting power component is fixed to the vehicle body. One end of the lifting arm is located at the bottom of the vehicle body, and the other end can pass through the vehicle body and connect to the lifting power component.

4. The wheel spacing adjustment mechanism for a transport vehicle according to claim 3, characterized in that, The lifting power component is a lifting cylinder, which is arranged vertically on the vehicle body, and the piston rod at the bottom of the lifting cylinder is connected to the lifting arm.

5. The wheel spacing adjustment mechanism for a transport vehicle according to claim 1, characterized in that, The adjustment unit is provided in two parts, which are respectively located on both sides of the vehicle body and are used to independently drive the two front wheels.

6. A wheel gauge adjustment mechanism for a transport vehicle according to claim 1 or 5, characterized in that, The adjustment unit includes an adjustment power component, which is arranged laterally on the vehicle body. A first rotating shaft is provided on the inner side of the front wheel, and the output end of the adjustment power component is connected to the first rotating shaft.

7. A wheel track adjustment mechanism for a transport vehicle according to claim 6, characterized in that, The adjusting power component is a linear motor, and the output shaft of the linear motor is connected to the first rotating shaft.

8. The wheel track adjustment mechanism for a transport vehicle according to claim 7, characterized in that, The adjustment unit also includes a coupling, which is located at the point where the output shaft of the linear motor is connected to the first rotating shaft.

9. A wheel track adjustment mechanism for a transport vehicle according to claim 1, characterized in that, It also includes a control unit, which is electrically connected to the lifting unit and the adjusting unit.

10. A transport vehicle, characterized in that, include: The wheel track adjustment mechanism as described in any one of claims 1-9.

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