Variable load type counterbalance forklift truck

Abstract

The invention discloses a variable load type counter weight forklift truck which comprises a truck body, front driving wheels, a counter weight position adjusting system, rear telescopic steering wheels and a portal frame system arranged on the front portion of the truck body. The counterweight position adjusting system comprises a counterweight, a connecting counterweight oil cylinder and a guide rail, the counterweight is slidably connected with the vehicle body through the guide rail, one end of the connecting counterweight oil cylinder is hinged with the vehicle body, and the other end is hinged with the counterweight for driving the counterweight to move back and forth along the guide rail; the rear telescopic steering wheel is arranged at the tail of the vehicle body and has the steering function and the telescopic function perpendicular to the ground plane. The stabilizing moment of the whole forklift can be changed by adjusting the front position and the rear position of the balance weight, and therefore the single forklift can safely adapt to different rated loads. And a user does not need to purchase a plurality of forklifts for goods with different weights, so that the fixed asset investment and the equipment management cost are obviously reduced.

Description

Technical Field

[0001] This invention relates to the field of engineering machinery technology, and in particular to a variable load counterbalance forklift. Background Technology

[0002] Counterbalance forklifts are widely used material handling equipment, and their load capacity is mainly determined by the weight and position of the counterweight. In existing technology, the rated load capacity of each counterbalance forklift is fixed, preset by the manufacturer according to the specifications and position of the counterweight. When users need to handle goods of varying weights, they often need to configure multiple forklifts with different load capacities. This not only increases the user's fixed asset investment but also complicates equipment management and maintenance. Especially when there are large differences in the weight distribution of goods or when there are temporary or urgent handling tasks, fixed-load forklifts cannot adapt flexibly, potentially leading to low equipment utilization or decreased handling efficiency.

[0003] Therefore, there is an urgent need for a forklift that can dynamically adjust its load capacity according to the actual weight of the goods being handled, so as to achieve multiple uses, reduce user costs, and improve equipment utilization. Summary of the Invention

[0004] In view of this, the present invention provides a variable load counterbalance forklift whose load capacity can be continuously or in stages adjusted according to the weight of the goods, thereby covering a wider load range with one device.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A variable load counterbalance forklift includes: a body, a front drive wheel, a counterweight position adjustment system, a rear telescopic steering wheel, and a mast system located at the front of the body; the counterweight position adjustment system includes a counterweight, a counterweight connecting cylinder, and a guide rail, the counterweight being slidably connected to the body via the guide rail, one end of the counterweight connecting cylinder being hinged to the body, and the other end being hinged to the counterweight, for driving the counterweight to move back and forth along the guide rail; the rear telescopic steering wheel is located at the rear of the body, and the rear telescopic steering wheel has a steering function and a telescopic function perpendicular to the ground plane.

[0007] Preferably, the guide rail is a U-shaped groove guide rail, which is fixedly installed on the vehicle body, and the counterweight is provided with a rotating shaft or slider that cooperates with the U-shaped groove guide rail.

[0008] Preferably, the connecting counterweight cylinder is connected to a hydraulic multi-way valve, and the stroke of the connecting counterweight cylinder is adjusted by controlling the hydraulic multi-way valve.

[0009] Preferably, the rear telescopic steering wheel includes a steering actuator and a telescopic cylinder, wherein the steering actuator is used to drive the wheel to steer, and the telescopic cylinder is used to drive the wheel assembly to extend and retract perpendicular to the ground plane.

[0010] Preferably, the steering actuator of the rear telescopic steering wheel is a steer-by-wire actuator.

[0011] Preferably, the gantry system is fixedly connected to the vehicle body and does not have a separate gantry tilting cylinder.

[0012] Preferably, the front drive wheel is a front electromagnetic drive wheel.

[0013] Preferably, the front electromagnetic drive wheel is connected to an electric drive control system.

[0014] Preferably, the center of gravity of the counterweight is located on the straight line of the sliding direction of the guide rail.

[0015] Preferably, the vehicle body is provided with a reinforced frame structure for mounting the connecting counterweight cylinder and the guide rail.

[0016] The beneficial effects of this invention are as follows:

[0017] 1. By adjusting the front and rear positions of the counterweight, the overall stabilizing torque of the forklift can be changed, allowing a single forklift to safely adapt to different rated loads. Users do not need to purchase multiple forklifts for goods of different weights, significantly reducing fixed asset investment and equipment management costs.

[0018] 2. When faced with multiple goods of varying weights or urgent handling tasks, operators can quickly adjust the forklift's load capacity without changing equipment, greatly improving the response speed and overall operational efficiency of logistics handling.

[0019] 3. The innovative rear telescopic steering wheel design not only enables steering but also adjusts the vehicle's posture by telescopically extending and retracting, compensating for changes in the center of gravity caused by counterweight movement or driving on slopes. This effectively prevents cargo from tipping over or slipping, ensuring stability and operational safety during slope operations and steering.

[0020] 4. The adoption of front electromagnetic drive wheels and steer-by-wire saves space occupied by traditional mechanical transmission and steering mechanisms. The mast is rigidly connected to the vehicle body, eliminating the need for mast tilting cylinders, resulting in a more compact and reliable structure and fewer maintenance points. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the variable load counterbalance forklift of the present invention.

[0022] Figure 2 This is a schematic diagram of the variable load counterbalance forklift of the present invention.

[0023] Figure 3 This is a schematic diagram of the rear telescopic steering wheel structure of the present invention on a complete vehicle.

[0024] Figure Labels

[0025] 1. Gantry system; 2. Front electromagnetic drive wheel; 3. Drive-by-wire steering actuator; 4. Counterweight; 5. Connecting counterweight cylinder; 6. Rear telescopic steering wheel; 7. U-shaped groove guide rail. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0027] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0028] The following is for reference. Figures 1 to 3 This invention describes a variable load counterbalance forklift in an embodiment of the present invention.

[0029] This application discloses a variable load counterbalance forklift, including: a vehicle body, a front drive wheel, a counterweight position adjustment system, a rear telescopic steering wheel 6, and a mast system 1 disposed at the front of the vehicle body; the counterweight position adjustment system includes a counterweight 4, a counterweight connecting cylinder 5, and a guide rail. The counterweight 4 is slidably connected to the vehicle body through the guide rail. One end of the counterweight connecting cylinder 5 is hinged to the vehicle body, and the other end is hinged to the counterweight 4, for driving the counterweight 4 to move back and forth along the guide rail; the rear telescopic steering wheel 6 is disposed at the rear of the vehicle body, and the rear telescopic steering wheel 6 has a steering function and a telescopic function perpendicular to the ground plane.

[0030] Specifically, the counterweight position adjustment system consists of a counterweight 4, a connecting counterweight cylinder 5, and a guide rail. The counterweight 4 is slidably mounted on the guide rail of the vehicle body. The connecting counterweight cylinder 5 serves as the drive mechanism; its cylinder body is hinged to the vehicle body, and its piston rod end is hinged to the counterweight 4. By extending and retracting the cylinder, the counterweight 4 can be moved back and forth along the guide rail (usually longitudinally of the vehicle body, i.e., in the X direction). The rear telescopic steering wheel 6 is mounted at the rear of the vehicle body; it is a multi-functional component integrating a steering mechanism and a telescopic mechanism capable of vertical lifting and lowering.

[0031] When lifting heavier loads, the control system commands the counterweight cylinder 5 to extend, pushing the counterweight 4 towards the rear of the vehicle. This increases the counterweight arm (the horizontal distance from the counterweight's center of gravity to the center of the front drive axle), generating a greater anti-tipping moment and allowing the forklift to safely handle heavier loads. Conversely, when handling light loads, the cylinder retracts, and the counterweight 4 moves forward to optimize the vehicle's center of gravity and save energy. During inclines and declines, or after the counterweight 4 has moved, the angle between the frame and the ground can be finely adjusted by controlling the extension and retraction of the rear telescopic steering wheels 6, keeping the mast vertical or at a suitable angle to ensure cargo stability.

[0032] The technical solution of this application fundamentally changes the traditional fixed load capacity mode of forklifts. Compared with the existing technology, its biggest progress lies in giving a single forklift a dynamically adjustable load capacity, solving the industry pain point that users must configure multiple models due to differences in cargo weight, realizing a huge leap in equipment versatility, and maintaining the overall stability of the vehicle during the dynamic adjustment process through the rear telescopic steering wheel 6.

[0033] In some embodiments, for example Figure 2 As shown, the guide rail is a U-shaped groove guide rail 7, which is fixedly installed on the vehicle body. The counterweight 4 is equipped with a rotating shaft or slider that cooperates with the U-shaped groove guide rail 7.

[0034] Specifically, the U-shaped groove guide rail 7 is fixed to the rear frame of the vehicle body by bolts or welding. A pivot or slider is installed at the corresponding position of the counterweight 4, and this pivot or slider is embedded in the U-shaped groove to form a sliding pair. The open design of the U-shaped groove facilitates the installation and maintenance of the counterweight 4 and its pivot / slider. The U-shaped structure provides good lateral and vertical constraints, ensuring that the counterweight 4 can only move smoothly and linearly along the length of the guide rail, preventing jamming or deviation during movement.

[0035] The U-shaped groove guide rail 7 used in this embodiment has a simple and reliable structure, and its processing and assembly technology is mature. Compared with simple slide bars or flat guide rails, the U-shaped groove provides better constraint on the counterweight 4, and can more effectively withstand various torques generated during the movement and operation of the counterweight 4, thereby improving the rigidity and durability of the adjustment system. This is an important optimization in the implementation details of the core variable load function.

[0036] In some embodiments, the connecting counterweight cylinder 5 is connected to a hydraulic multi-way valve, and the stroke of the connecting counterweight cylinder 5 is adjusted by controlling the hydraulic multi-way valve.

[0037] Specifically, the hydraulic multi-way valve is a commonly used hydraulic control component in construction machinery, installed in the hydraulic system of a forklift. Its valve core position is controlled by an electrical signal sent by the operator via a lever or button, thereby precisely adjusting the flow and direction of hydraulic oil to the two chambers of the counterweight cylinder 5. The operator issues commands from the cab, and the controller actuates the solenoid of the hydraulic multi-way valve, changing the oil circuit and driving the counterweight cylinder 5 to extend or retract to a predetermined position. The hydraulic system can be equipped with a stroke sensor or position sensor to achieve closed-loop control, allowing the counterweight 4 to stop at any set position.

[0038] In this embodiment, control is achieved through a hydraulic multi-way valve, a reliable and mature technology in engineering machinery. This ensures a smooth, controllable, and powerful adjustment process for the counterweight at position 4. Compared to purely mechanical adjustment, hydraulic adjustment is less labor-intensive and facilitates precise displacement control and self-locking, guaranteeing the reliability and convenience of load adjustment.

[0039] In some embodiments, the rear telescopic steering wheel 6 includes a steering actuator and a telescopic cylinder. The steering actuator is used to drive the wheel to steer, and the telescopic cylinder is used to drive the wheel assembly to extend and retract perpendicular to the ground plane.

[0040] Specifically, the steering actuator can be an independent steering motor or hydraulic steering cylinder, responsible for driving the wheel hub steering. The telescopic cylinder is arranged vertically, with its cylinder body connected to the vehicle body and its piston rod connected to the wheel suspension or load-bearing mechanism. The steering function operates independently to achieve the steering of the entire vehicle. The telescopic function is independently controlled: when the system detects that the vehicle is going uphill, downhill, or that the counterweight position has changed, it commands the telescopic cylinder to extend or retract, thereby raising or lowering the rear of the vehicle, adjusting the mast posture, and keeping the forks level or at the required tilt angle.

[0041] In this embodiment, the steering and attitude adjustment functions are modularly integrated into a single wheel assembly, resulting in a compact design and saving space. Compared to setting up a separate, complex linkage or lifting mechanism for attitude adjustment, this solution has a simpler structure, clearer functional division, and clearer control logic, effectively reducing system complexity and failure rate.

[0042] In some embodiments, for example Figure 1 and Figure 2 As shown, the steering actuator of the rear telescopic steering wheel 6 is a steer-by-wire actuator 3. Specifically, the operator turns the steering wheel (or joystick) to generate an angle signal, which is transmitted to the vehicle controller and the steer-by-wire controller. The controller calculates the required steering angle of the rear wheels and drives the steering actuator to achieve steering. The entire process involves no mechanical connection, only electrical signal transmission.

[0043] In this embodiment, steer-by-wire is employed, eliminating the complex mechanical steering linkage between the steering wheel and rear wheels. This simplifies the vehicle body structure, improves chassis space utilization, and facilitates the arrangement of other components (such as the counterweight guide rails). Furthermore, steer-by-wire offers faster response and is easier to integrate with vehicle stability control algorithms, representing the future direction of modern engineering machinery steering systems.

[0044] In some embodiments, for example Figure 3 As shown, the mast system 1 is fixedly connected to the vehicle body and does not have an independent mast tilt cylinder. Specifically, the mast itself does not have a tilting degree of freedom. When it is necessary to tilt the forks forward (for easier loading) or backward (to stabilize the cargo during transport), the overall vehicle posture is changed by controlling the extension and retraction of the rear telescopic steering wheel 6, thereby indirectly achieving the change in the angle of the forks relative to the ground. This improvement represents a redistribution and integration of the functions of the entire vehicle system. Eliminating the mast tilt cylinder simplifies the mast structure, reduces manufacturing costs and maintenance requirements, and improves the connection rigidity and reliability at the mast root.

[0045] In some embodiments, the front drive wheel is a front electromagnetic drive wheel 2. Specifically, the electric drive controller receives throttle and braking signals and controls the motor integrated in the wheel to output torque, directly driving the wheel to rotate. Using the front electromagnetic drive wheel 2 results in an extremely short transmission chain and high transmission efficiency. It frees up the central space of the vehicle body occupied by the traditional drive axle, which can be used to arrange the battery pack or provide more space for the counterweight 4 moving mechanism. This is a key technology selection for optimizing the overall vehicle layout and supporting the realization of core innovative structures.

[0046] In some embodiments, the front electromagnetic drive wheel 2 is connected to an electric drive control system. Specifically, the electric drive control system realizes comprehensive control of the forklift's driving, speed regulation, and braking energy recovery, and coordinates with the hydraulic system, steering system, etc. The electric drive control system is the core of the electric forklift, and its combination with systems such as steer-by-wire and adjustable counterweight 4 provides the foundation for realizing intelligent and integrated control of the entire vehicle. It makes precise and coordinated control of various vehicle movements possible, improving the overall energy efficiency and handling performance of the vehicle.

[0047] In some embodiments, for example Figure 2 As shown, the center of gravity of counterweight 4 is located on the straight line of the sliding direction of the guide rail. This ensures that the balancing torque generated by counterweight 4 during movement is always along the longitudinal direction of the vehicle, and will not generate additional torsional torque or lateral force on the guide rail. This is an important design principle to ensure the smooth, low-resistance, and reliable operation of the counterweight position adjustment system. It effectively prevents counterweight 4 from "gripping" or jamming during movement, reduces the load on the drive cylinder, and extends the service life of the guide rail and sliding components. It is a key detail for improving the motion accuracy of the mechanism in engineering practice.

[0048] In some embodiments, the vehicle body is provided with a reinforced frame structure for mounting and connecting the counterweight cylinder 5 and the guide rail. This reinforced frame, as the main load-bearing carrier of the counterweight position adjustment system, bears the load of the counterweight 4, the pushing and pulling force of the cylinder, and various dynamic loads during vehicle operation, effectively transmitting them to the entire vehicle frame. It ensures the connection stiffness and strength of the mounting point under extreme conditions of counterweight 4 movement and forklift heavy-duty operation, preventing malfunctions or structural damage due to localized deformation, and guaranteeing the long-term safety and reliability of the entire variable load system.

[0049] Other configurations and operations of the variable load counterbalance forklift according to embodiments of the present invention are known to those skilled in the art and will not be described in detail here.

[0050] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0051] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A variable load counterbalance forklift, characterized in that, include: Body, front drive wheels, counterweight position adjustment system, rear telescopic steering wheel and mast system located at the front of the body; The counterweight position adjustment system includes a counterweight, a connecting counterweight cylinder, and a guide rail. The counterweight is slidably connected to the vehicle body via the guide rail. One end of the connecting counterweight cylinder is hinged to the vehicle body, and the other end is hinged to the counterweight, for driving the counterweight to move back and forth along the guide rail. The rear telescopic steering wheel is located at the rear of the vehicle body, and the rear telescopic steering wheel has a steering function and a telescopic function perpendicular to the ground plane.

2. The variable load counterbalance forklift according to claim 1, characterized in that, The guide rail is a U-shaped groove guide rail, which is fixedly installed on the vehicle body. The counterweight is provided with a rotating shaft or slider that cooperates with the U-shaped groove guide rail.

3. The variable load counterbalance forklift according to claim 1 or 2, characterized in that, The connecting counterweight cylinder is connected to a hydraulic multi-way valve, and the stroke of the connecting counterweight cylinder is adjusted by controlling the hydraulic multi-way valve.

4. The variable load counterbalance forklift according to claim 1, characterized in that, The rear telescopic steering wheel includes a steering actuator and a telescopic cylinder. The steering actuator is used to drive the wheel to steer, and the telescopic cylinder is used to drive the wheel assembly to extend and retract perpendicular to the ground plane.

5. The variable load counterbalance forklift according to claim 4, characterized in that, The steering actuator of the rear telescopic steering wheel is a steer-by-wire actuator.

6. The variable load counterbalance forklift according to claim 1, characterized in that, The gantry system is fixedly connected to the vehicle body and does not have a separate gantry tilting cylinder.

7. The variable load counterbalance forklift according to claim 1, characterized in that, The front drive wheel is a front electromagnetic drive wheel.

8. The variable load counterbalance forklift according to claim 7, characterized in that, The front electromagnetic drive wheel is connected to an electric drive control system.

9. The variable load counterbalance forklift according to claim 1, characterized in that, The center of gravity of the counterweight is located on the straight line of the sliding direction of the guide rail.

10. The variable load counterbalance forklift according to claim 1, characterized in that, The vehicle body is equipped with a reinforced frame structure for mounting the connecting counterweight cylinder and the guide rail.

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