Power distribution system and method for mini skid steer loader

Abstract

The invention discloses a power distribution system and method for a mini skid loader, and the system achieves the setting of a walking power proportion and the activation of a converging function through the cooperative work of a power system, a walking proportion control hydraulic system, a double-control accessory hydraulic system and an intelligent display and operation system, thereby achieving the flexible distribution of the total power. The system comprises an engine, a pilot pump, a working pump, a walking proportional valve, a hydraulic control handle valve, a multi-way valve, a reversing confluence integrated valve and other key assemblies, an intelligent display screen and a controller. The method comprises a walking control stage, a swash plate adjustment stage, a walking execution stage, an accessory independent control stage, a confluence control stage and an accessory cooperative control stage, three modes of custom, common and accessory are supported, the power distribution proportion is adjustable, the confluence function can be activated, the equipment use convenience and the working efficiency are remarkably improved, an engine is protected, and the equipment adaptability is enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering vehicles, and in particular to a power distribution system and method for a mini skid steer loader. Background Art

[0002] Mini skid-steer loaders, as small, versatile construction machinery, are widely used in construction, agriculture, gardening, and other fields due to their compact structure and flexible operation. In actual use, mini skid-steer loaders often need to simultaneously perform travel and attachment operations (such as lifting, loading, and crushing). However, due to engine power limitations, when both travel and attachment operation are operating at maximum power, the engine's power output is often exceeded, resulting in undesirable issues such as stalling (a sharp drop in engine speed) and flameout.

[0003] Currently, conventional mini skid-steer loaders lack effective power distribution control mechanisms. Preventing engine stalling requires a high level of operator skill. During operation, users must constantly monitor the engine's operating status. If they detect an imminent stall, they must proactively reduce the speed of the vehicle and attachments to minimize power demand. This approach not only increases user workload and reduces efficiency, but also, due to the uncertainty of human judgment, creates the risk of engine stalling, impacting the equipment's normal operation and service life. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the above technical defects and provide a mini skid loader power distribution system and method. The total power that can be provided by the power system is manually distributed through two aspects: the operator's setting of the walking power ratio and whether the operator activates the merging function. Different distribution schemes can be implemented according to different working conditions, avoiding the operator repeatedly adjusting the action rate during the operation to reduce the power demand to cope with the engine stalling situation, thereby improving the convenience of use and work efficiency of the equipment.

[0005] To solve the above technical problems, the present invention provides a technical solution: a power distribution system for a mini skid steer loader, comprising:

[0006] The power system includes an engine, a fuel tank, a pilot pump and a working pump. The engine drives the pilot pump to output hydraulic power to the travel proportional control hydraulic system, and simultaneously drives the working pump to output hydraulic power to the dual-control attachment hydraulic system.

[0007] The travel proportional control hydraulic system includes a travel proportional valve, a hydraulically controlled handle valve, a travel pump A, a travel motor A, a travel pump B and a travel motor B. The pilot pump is connected to the travel proportional valve and the hydraulically controlled handle valve in sequence through a first oil inlet line, and the hydraulically controlled handle valve is connected to the oil tank through a first oil return line. The hydraulically controlled handle valve controls the swash plate angles of the travel pumps A and B respectively through a first closed-loop oil circuit and a second closed-loop oil circuit. The travel pump A forms a closed circuit with the travel motor A through the A circulation oil circuit, and the travel pump B forms a closed circuit with the travel motor B through the B circulation oil circuit.

[0008] The dual-control attachment hydraulic system includes a multi-way valve, a reversing and merging integrated valve, a left attachment quick connector, an attachment motor, a right attachment quick connector and an attachment cylinder. The outlet 1 of the working pump is connected to the multi-way valve and the reversing and merging integrated valve through the second oil inlet line A, and the outlet 2 of the working pump is directly connected to the reversing and merging integrated valve through the second oil inlet line B. The reversing and merging integrated valve has a left attachment circulating oil circuit connected to the left attachment quick connector and the attachment motor and a second return oil circuit connected to the oil tank. The multi-way valve is connected to the right attachment quick connector and the attachment cylinder through the right attachment circulating oil circuit.

[0009] An intelligent display and operating system includes an intelligent display screen, a controller and a wiring harness, wherein the controller is electrically connected to a travel proportional valve and a reversing and converging integrated valve.

[0010] Furthermore, the hydraulically controlled handle valve forms a closed-loop connection with the swash plate control servo cylinders of the travel pump A and the travel pump B through the first closed-loop oil circuit and the second closed-loop oil circuit respectively. The lead-out section of the travel proportional valve is provided with a bypass oil circuit that diverts to the first return oil circuit. The first return oil circuit is connected to the oil tank to form a pressure release channel.

[0011] Furthermore, the reversing and merging integrated valve includes a reversing valve and a two-position two-way valve. The reversing valve is mechanically controlled by the right accessory operating handle. When the merging function is turned on, the two-position two-way valve blocks the return oil passage of the working pump outlet one, so that the two oil flows merge in the reversing and merging integrated valve and output to the left accessory circulating oil circuit.

[0012] Furthermore, when the multi-way valve performs the reversing action, its outlet oil enters the rodless chamber of the accessory cylinder through the right accessory circulation oil circuit, and at the same time, the rod chamber oil of the accessory cylinder directly returns to the oil tank through the multi-way valve. At this time, the oil at the outlet of the working pump and the reversing merging integrated valve form an oil circuit isolation.

[0013] Furthermore, the travel proportional valve receives a current signal to control its opening, and linear control of the travel speed is achieved by adjusting the proportion of oil entering the hydraulic control handle valve, and the remaining oil returns to the oil tank through the first oil return line to form a pressure balance system.

[0014] The present application also provides a power distribution method for a mini skid steer loader, including the following control process:

[0015] S1, travel control stage: The engine drives the pilot pump to output hydraulic oil to the travel proportional valve. The controller generates a PWM signal based on the power distribution parameters input by the intelligent display screen, adjusts the opening ratio of the travel proportional valve, and distributes part of the hydraulic oil to the swash plate control servo cylinder of travel pump A and travel pump B through the hydraulic control handle valve. The remaining hydraulic oil returns to the fuel tank through the first return oil circuit;

[0016] S2, swash plate adjustment stage: The hydraulic control handle valve delivers hydraulic oil to the swash plate control servo cylinders of travel pump A and travel pump B respectively according to the operating instructions. By changing the cylinder stroke, the swash plate inclination angles of travel pump A and travel pump B are adjusted synchronously, thereby controlling the oil flow and direction of circulation oil circuit A and circulation oil circuit B;

[0017] S3, travel execution stage: The hydraulic oil output by travel pump A and travel pump B respectively drives travel motor A and travel motor B to form a closed loop. The loader's forward, reverse and steering movements are achieved through the differential rotation of travel motor A and travel motor B.

[0018] S4, attachment independent control stage: When the multi-way valve is not actuated, the first-way hydraulic oil output by the working pump is directly returned to the oil tank through the multi-way valve and the reversing and merging integrated valve, and the second-way hydraulic oil is controlled by the reversing valve of the reversing and merging integrated valve to drive the attachment motor connected to the left attachment quick connector;

[0019] S5, confluence control stage: When the confluence function is activated, the first hydraulic oil of the working pump passes through the multi-way valve and merges with the second hydraulic oil in the reversing confluence integrated valve to jointly drive the attachment motor, increasing the output flow to 200% of the independent control stage;

[0020] S6, accessory coordinated control stage: When the multi-way valve is operated to reverse, the first hydraulic oil drives the accessory cylinder to extend and retract through the right accessory quick connector, and the second hydraulic oil maintains an independent control state.

[0021] Furthermore, the activation of the confluence function in step S5 is achieved by:

[0022] The smart display screen sends a confluence instruction to the controller;

[0023] The controller controls the two-position two-way valve in the reversing merging integrated valve to block the direct oil return path, so that the first hydraulic oil and the second hydraulic oil are merged and output to the left attachment quick connector.

[0024] Furthermore, the setting of the power allocation parameters includes:

[0025] In custom mode, the walking power distribution ratio can be adjusted in stages within the range of 20%-100% through the smart display screen;

[0026] In normal mode, the walking power is forcibly locked at 100% rated power;

[0027] In attachment mode, the travel power is forcibly locked to the preset ratio, and the remaining power is distributed to the dual-control attachment hydraulic system.

[0028] Furthermore, the power status display process is also included:

[0029] The controller collects the current signal of the travel proportional valve and the status signal of the reversing and converging integrated valve in real time;

[0030] The intelligent display generates a visual power allocation interface, where:

[0031] Total power is represented by an outline icon;

[0032] The walking power ratio area dynamically expands or shrinks according to the current allocation ratio;

[0033] The attachment power ratio area switches from 50% to 100% when confluence is activated, and real-time feedback is provided through changes in the color block area.

[0034] The advantages of the present invention compared with the prior art are:

[0035] 1. Improved ease of use: Operators can set the travel power ratio and activate the merging function through simple operations according to different working conditions. There is no need to always pay attention to the working status of the engine and repeatedly adjust the action rate, which greatly reduces the difficulty of operation and improves the ease of use of the equipment.

[0036] 2. Improve work efficiency: Since power can be reasonably allocated according to actual working conditions, equipment shutdown and adjustment due to engine jamming can be avoided, operation interruption time can be reduced, thereby improving work efficiency.

[0037] 3. Protect the engine: By real-time monitoring of the working status of the engine and each motor, and adjusting the power distribution strategy according to actual conditions, it ensures that the engine always operates within a safe power range, effectively avoiding the occurrence of adverse phenomena such as engine jamming and flameout, and extending the service life of the engine.

[0038] 4. Enhanced equipment adaptability: The power distribution control system of the present invention can implement different power distribution schemes according to different working conditions, enabling the mini skid steer loader to adapt to more complex and changeable working environments, thereby improving the adaptability and versatility of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1This is a schematic diagram of the overall layout of a power distribution system for a mini skid loader of the present application;

[0040] Figure 2 yes Figure 1 Schematic diagram of the power system;

[0041] Figure 3 yes Figure 1 Schematic diagram of the hydraulic system for mid-travel proportional control;

[0042] Figure 4 yes Figure 1 Schematic diagram of the hydraulic system of the dual-control attachment;

[0043] Figure 5 yes Figure 1 Schematic diagram of intelligent display and operating system;

[0044] Figure 6 This is the hydraulic principle diagram of the travel proportional control hydraulic system of this application;

[0045] Figure 7 This is the hydraulic principle diagram of the hydraulic system of the dual-control attachment of this application;

[0046] Figure 8 yes Figure 5 The intelligent display and operating system's walking power distribution ratio setting operation interface.

[0047] As shown in the figure: 1. Engine, 2. Fuel tank, 3. Pilot pump, 4. Working pump, 5. Travel proportional valve, 6. Hydraulic control handle valve, 7. Travel pump A, 8. Travel motor A, 9. Travel pump B, 10. Travel motor B, 11. First oil inlet line, 12. First closed-loop oil line, 13. Second closed-loop oil line, 14. Circulating oil line A, 15. Circulating oil line B, 16. Multi-way valve, 17. Reversing and converging integrated valve, 18. Left attachment quick Connector, 19. Attachment motor, 20. Right attachment quick connector, 21. Attachment cylinder, 22. Second oil inlet line A, 23. Second oil inlet line B, 24. Left attachment circulating oil line, 25. Second oil return line, 26. Right attachment circulating oil line, 27. Smart display screen, 28. Controller, 29. Wiring harness, 30. First oil return line, 31. Reversing valve, 32. Two-position two-way valve, 33. Right attachment operating handle, 34. Left attachment electric switch. DETAILED DESCRIPTION

[0048] The present invention will be described in further detail below with reference to the accompanying drawings.

[0049] The specific embodiments of the present invention are further described below with reference to the accompanying drawings, wherein the same parts are represented by the same reference numerals.

[0050] It should be noted that the words "front", "rear", "left", "right", "up" and "down" used in the following description refer to directions in the accompanying drawings, and the words "inside" and "outside" refer to directions toward or away from the geometric center of a specific component, respectively.

[0051] In order to make the contents of the present invention more clearly understood, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0052] Reference Attachment Figure 1 -Attached Figure 7 This application provides a mini skid steer loader power distribution system, the core of which is to efficiently and flexibly distribute power to meet the needs of different working conditions. The system mainly includes:

[0053] The power system, serving as the energy source for the entire system, consists of an engine 1, a fuel tank 2, a pilot pump 3, and a working pump 4. As the core of the power, engine 1 drives pilot pump 3 to output hydraulic power to the travel proportional control hydraulic system, and simultaneously drives working pump 4 to output hydraulic power to the dual-control attachment hydraulic system, achieving efficient power distribution and utilization.

[0054] Specifically, the travel proportional control hydraulic system is responsible for controlling the loader's travel motion. It includes a travel proportional valve 5, a hydraulically controlled handle valve 6, a travel pump A7, a travel motor A8, a travel pump B9, and a travel motor B10. The pilot pump 3 is connected to the travel proportional valve 5 and the hydraulically controlled handle valve 6 in sequence via the first oil inlet line 11. The hydraulically controlled handle valve 6 is connected to the fuel tank 2 via the first oil return line 30, forming a complete hydraulic circuit. The hydraulically controlled handle valve 6 controls the swash plate angles of the travel pumps A7 and B9, respectively, via the first closed-loop oil circuit 12 and the second closed-loop oil circuit 13, thereby adjusting the output flow and direction of the travel pumps. The travel pump A7 forms a closed circuit with the travel motor A8 via the A circulation oil circuit 14, and the travel pump B9 forms a closed circuit with the travel motor B10 via the B circulation oil circuit 15, jointly driving the loader's forward, reverse, and steering movements.

[0055] The dual-control attachment hydraulic system is responsible for controlling the movement of the loader's attachments. It includes a multi-way valve 16, a reversing and merging integrated valve 17, a left attachment quick connector 18, an attachment motor 19, a right attachment quick connector 20, and an attachment cylinder 21. The first outlet of the working pump 4 is connected to the multi-way valve 16 and the reversing and merging integrated valve 17 via the second oil inlet line A22, while the second outlet of the working pump 4 is directly connected to the reversing and merging integrated valve 17 via the second oil inlet line B23, achieving flexible distribution of hydraulic oil. The reversing and merging integrated valve 17 has a left attachment circulation oil circuit 24 connected to the left attachment quick connector 18 and the attachment motor 19, and a second return oil circuit 25 connected to the oil tank 2. The multi-way valve 16 is connected to the right attachment quick connector 20 and the attachment cylinder 21 via the right attachment circulation oil circuit 26, together forming the control circuit of the attachment hydraulic system.

[0056] The intelligent display and operating system serve as a bridge for human-machine interaction. It includes an intelligent display screen 27, a controller 28, and a wiring harness 29. The controller 28 is electrically connected to the travel proportional valve 5 and the reversing and converging integrated valve 17, enabling precise control of the hydraulic system. The intelligent display screen 27 provides an intuitive interface, allowing operators to easily set operating modes and adjust power distribution ratios.

[0057] In a specific embodiment, the hydraulically controlled handle valve 6 forms closed-loop connections with the swashplate control servo cylinders of travel pumps A7 and B9 via first and second closed-loop oil circuits 12 and 13, respectively, ensuring precise adjustment of the travel pump swashplate angles. Furthermore, a bypass oil circuit is provided at the outlet of the travel proportional valve 5, diverting flow to the first oil return circuit 30. This first oil return circuit 30 connects to the fuel tank 2 to form a pressure relief channel, effectively preventing damage to components caused by excessive system pressure.

[0058] In another embodiment, the design of the reversing and merging integrated valve 17 is particularly ingenious. It comprises a reversing valve 31 and a two-position, two-way valve 32. The reversing valve 31 is mechanically controlled by the right attachment operating handle 33, enabling flexible reversing of the attachment hydraulic system. When the merging function is activated, the two-position, two-way valve 32 blocks the return oil path from outlet 1 of the working pump 4, allowing the two oil flows to merge within the reversing and merging integrated valve 17 and be output to the left attachment circulating oil circuit 24, thereby increasing the output power of the attachment hydraulic system.

[0059] When the multi-way valve 16 performs a reversing action, the oil at its outlet enters the rodless chamber of the attachment cylinder 21 through the right attachment circulation oil circuit 26. At the same time, the oil in the rod chamber of the attachment cylinder 21 returns directly to the fuel tank 2 through the multi-way valve 16. At this time, the oil at the first outlet of the working pump 4 is isolated from the reversing and merging integrated valve 17, ensuring independent control of the attachment hydraulic system.

[0060] Furthermore, the travel proportional valve 5 receives a current signal to control its opening, linearly controlling the travel speed by adjusting the proportion of oil entering the hydraulic control handle valve 6. The remaining oil returns to the oil tank 2 through the first oil return line 30, forming a pressure-balanced system and ensuring stable operation of the travel hydraulic system.

[0061] The present application also provides a power distribution method for a mini skid steer loader, including the following control process:

[0062] S1, travel control stage: Engine 1 drives pilot pump 3 to output hydraulic oil to travel proportional valve 5. Controller 28 generates PWM signal based on power distribution parameters input by intelligent display 27, adjusts the opening ratio of travel proportional valve 5, and distributes part of the hydraulic oil to the swash plate control servo cylinder of travel pump A7 and travel pump B9 through hydraulic control handle valve 6. The remaining hydraulic oil returns to tank 2 through first oil return line 30.

[0063] S2, swash plate adjustment stage: The hydraulic control handle valve 6 delivers hydraulic oil to the swash plate control servo cylinders of travel pumps A7 and B9 respectively according to the operating instructions. By changing the cylinder stroke, the swash plate inclination angles of travel pumps A7 and B9 are synchronously adjusted, thereby controlling the oil flow and direction of circulation oil circuit A 14 and circulation oil circuit B 15;

[0064] S3, travel execution phase: The hydraulic oil output by travel pumps A7 and B9 drives travel motors A8 and B10 respectively to form a closed loop. The loader's forward, reverse, and steering movements are achieved through the differential rotation of travel motors A8 and B10.

[0065] S4, attachment independent control stage: When the multi-way valve 16 is not actuated, the first-way hydraulic oil output by the working pump 4 is directly returned to the oil tank 2 through the multi-way valve 16 and the reversing and merging integrated valve 17. The second-way hydraulic oil is controlled by the reversing valve of the reversing and merging integrated valve 17 and then drives the attachment motor 19 connected to the left attachment quick connector 18;

[0066] S5, merging control stage: When the merging function is activated, the first hydraulic oil of the working pump 4 passes through the multi-way valve 16 and merges with the second hydraulic oil in the reversing merging integrated valve 17, and together drives the attachment motor 19, so that the output flow rate is increased to 200% of the independent control stage;

[0067] S6, accessory coordinated control stage: When the multi-way valve 16 is operated to change direction, the first hydraulic oil drives the accessory cylinder 21 to extend and retract through the right accessory quick connector 20, and the second hydraulic oil maintains an independent control state.

[0068] In one embodiment, activation of the confluence function in step S5 is achieved by:

[0069] The intelligent display screen 27 sends a merging instruction to the controller 28;

[0070] The controller 28 controls the two-position two-way valve in the reversing merging integrated valve 17 to block the direct oil return path, so that the first hydraulic oil and the second hydraulic oil are merged and output to the left attachment quick connector 18.

[0071] In one embodiment, the setting of the power allocation parameters includes:

[0072] In the custom mode, the walking power distribution ratio is set through the intelligent display 27 in a graded adjustment range of 20%-100%;

[0073] In normal mode, the walking power is forcibly locked at 100% rated power;

[0074] In attachment mode, the travel power is forcibly locked to the preset ratio, and the remaining power is distributed to the dual-control attachment hydraulic system.

[0075] In one embodiment, the power status display process is further included:

[0076] The controller 28 collects the current signal of the travel proportional valve 5 and the status signal of the reversing and converging integrated valve 17 in real time;

[0077] The intelligent display screen 27 generates a visual power distribution interface, wherein:

[0078] Total power is represented by an outline icon;

[0079] The walking power ratio area dynamically expands or shrinks according to the current allocation ratio;

[0080] The attachment power ratio area switches from 50% to 100% when confluence is activated, and real-time feedback is provided through changes in the color block area.

[0081] This method achieves flexible switching and efficient allocation of travel and attachment control through the coordinated operation of components such as the intelligent display 27, controller 28, travel proportional valve 5, and reversing and converging integrated valve 17. The specific control process includes the travel control phase, the swash plate adjustment phase, the travel execution phase, the independent attachment control phase, the converging control phase, and the coordinated attachment control phase.

[0082] In the merging control stage, when the merging function is activated, the intelligent display screen 27 sends a merging instruction to the controller 28. The controller 28 controls the two-position two-way valve in the reversing merging integrated valve 17 to block the direct oil return path, so that the first hydraulic oil and the second hydraulic oil are merged and output to the left attachment quick connector 18, thereby improving the output power of the attachment hydraulic system.

[0083] Setting power distribution parameters is also a key aspect of this invention. In custom mode, the operator can use the intelligent display 27 to adjust the travel power distribution ratio in a graduated range of 20%-100%. In normal mode, travel power is locked at 100% rated power. In attachment mode, travel power is locked at a preset ratio, with the remaining power allocated to the dual-control attachment hydraulic system. This flexible power distribution method meets the needs of different operating conditions.

[0084] In addition, the present invention also includes a power status display process. The controller 28 collects the current signal of the travel proportional valve 5 and the status signal of the reversing confluence integrated valve 17 in real time, and the intelligent display screen 27 generates a visual power distribution interface. The total power is represented by an outline icon, and the travel power proportion area dynamically expands or contracts according to the current distribution ratio. The accessory power proportion area switches from 50% to 100% when the confluence is activated, and real-time feedback is provided through changes in the color block area. This intuitive display method facilitates the operator to monitor and adjust the power distribution status.

[0085] Hydraulic power is supplied to the left attachment quick connector 18 via the reversing and converging integrated valve 17. The operator controls this via the left attachment electrical switch 34. This is a hold-type switch that allows the attachment connected to the left attachment quick connector 18 to maintain high-speed rotation and provides reversing control of its hydraulic power. This design enhances the flexibility and convenience of attachment operation.

[0086] Figure 5The intelligent display and operating system shown consists of an intelligent display 27, a controller 28, and a wiring harness 29. The operator can use the intelligent display 27 to set the mini skid loader's operating mode, including custom mode, normal mode, and attachment mode. In custom mode, the operator can use the intelligent display 27 to set the travel power distribution ratio, with five settings available: 20%, 40%, 60%, 80%, and 100%. The operator can reduce or increase the power allocated to the travel portion. The corresponding PWMI (pulse width modulation) signal is sent via the intelligent display 27 and transmitted to the controller 28 via the wiring harness 29. The controller 28 then outputs a corresponding current signal to the travel proportional valve 5 through the wiring harness 29 to control the ratio of the pilot control pressure. The higher the user-set ratio, the greater the current signal received by the travel proportional valve 5, the greater the ratio of the pilot control pressure received by travel pumps A and B, and the greater the hydraulic power output by travel pumps A and B. In normal mode, the default travel power allocation ratio is 100% and cannot be adjusted; in attachment mode, the default travel power allocation ratio is 60% and cannot be adjusted. The operator can also set the merging mode on or off through the smart display 27. By default, the maximum power usage limit of the dual-control attachment hydraulic system in the non-merging state is 50% of the attachment power, and the maximum power usage limit of the dual-control attachment hydraulic system in the merging state is 100% of the attachment power.

[0087] Figure 8 The smart display screen 27 shown can also display the power distribution status of the mini skid loader. The total power of the power system is virtualized into an outline icon as a whole, and the interior of the outline is filled with travel power and attachment power, and displayed in different colors. When the operator increases or decreases the travel power ratio, the proportion of the area representing the travel power color will also increase or decrease accordingly. When the operator does not activate the merging mode, the attachment power ratio is displayed as 50%; after the operator activates the merging mode, the attachment power ratio will change to 100%. When the merging mode is turned off and on, the proportion of the area representing the attachment power color will also be different accordingly. It should be noted that the proportion of the areas of different colors of travel power and attachment power in the virtual outline icon of the total power of the power system is only to show the operator the trend of the proportion change, and does not represent the actual value of the proportion of the mini skid loader's travel power and attachment power in the total power distribution of the power system.

[0088] The present invention and its embodiments are described above. This description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by this and, without departing from the purpose of the present invention, designs structures and embodiments similar to this technical solution without inventiveness, they shall fall within the scope of protection of the present invention.

Claims

1. A power distribution system for a mini skid steer loader, characterized in that: include: A power system comprises an engine (1), a fuel tank (2), a pilot pump (3) and a working pump (4), wherein the engine (1) drives the pilot pump (3) to output hydraulic power to a travel proportional control hydraulic system, and simultaneously drives the working pump (4) to output hydraulic power to a dual-control attachment hydraulic system; The travel proportional control hydraulic system comprises a travel proportional valve (5), a hydraulic control handle valve (6), a travel pump A (7), a travel motor A (8), a travel pump B (9) and a travel motor B (10); the pilot pump (3) is connected to the travel proportional valve (5) and the hydraulic control handle valve (6) in sequence through a first oil inlet line (11); the hydraulic control handle valve (6) is connected to the oil tank (2) through a first oil return line (30); the hydraulic control handle valve (6) controls the swash plate angles of the travel pump A (7) and the travel pump B (9) respectively through a first closed-loop oil line (12) and a second closed-loop oil line (13); the travel pump A (7) forms a closed loop with the travel motor A (8) through an A circulation oil line (14); and the travel pump B (9) forms a closed loop with the travel motor B (10) through a B circulation oil line (15); The dual-control attachment hydraulic system comprises a multi-way valve (16), a reversing and merging integrated valve (17), a left attachment quick connector (18), an attachment motor (19), a right attachment quick connector (20) and an attachment oil cylinder (21); an outlet 1 of the working pump (4) is connected to the multi-way valve (16) and the reversing and merging integrated valve (17) via a second oil inlet line A (22); an outlet 2 of the working pump (4) is directly connected to the reversing and merging integrated valve (17) via a second oil inlet line B (23); the reversing and merging integrated valve (17) has a left attachment circulation oil circuit (24) connected to the left attachment quick connector (18) and the attachment motor (19) and a second oil return circuit (25) connected to the oil tank (2); the multi-way valve (16) is connected to the right attachment quick connector (20) and the attachment oil cylinder (21) via a right attachment circulation oil circuit (26); An intelligent display and operating system comprises an intelligent display screen (27), a controller (28) and a wiring harness (29), wherein the controller (28) is electrically connected to a travel proportional valve (5) and a reversing confluence integrated valve (17).

2. The mini skid steer loader power distribution system according to claim 1, characterized in that: The hydraulic control handle valve (6) is connected to the swash plate control servo cylinders of the travel pump A (7) and the travel pump B (9) through a first closed-loop oil circuit (12) and a second closed-loop oil circuit (13) to form a closed-loop connection. The lead-out section of the travel proportional valve (5) is provided with a bypass oil circuit that branches to a first oil return circuit (30). The first oil return circuit (30) is connected to the oil tank (2) to form a pressure release channel.

3. The power distribution system for a mini skid steer loader according to claim 1, characterized in that: The reversing merging integrated valve (17) comprises a reversing valve (31) and a two-position two-way valve (32). The reversing valve (31) is mechanically controlled by a right attachment operating handle (33). When the merging function is turned on, the two-position two-way valve (32) blocks the return oil passage of the working pump (4) outlet 1, so that two oil flows merge in the reversing merging integrated valve (17) and are output to the left attachment circulating oil circuit (24).

4. The power distribution system for a mini skid steer loader according to claim 1, characterized in that: When the multi-way valve (16) performs the reversing action, the oil at its outlet enters the rodless chamber of the attachment cylinder (21) through the right attachment circulation oil circuit (26), and at the same time, the oil in the rod chamber of the attachment cylinder (21) directly returns to the oil tank (2) through the multi-way valve (16). At this time, the oil at the outlet 1 of the working pump (4) forms an oil circuit isolation with the reversing merging integrated valve (17).

5. The power distribution system for a mini skid steer loader according to claim 1, characterized in that: The travel proportional valve (5) receives a current signal to control its opening, and linear control of the travel speed is achieved by adjusting the proportion of oil entering the hydraulic control handle valve (6). The remaining oil returns to the oil tank (2) through the first oil return line (30) to form a pressure balance system.

6. A power distribution method for a mini skid steer loader, characterized in that: The method is implemented through the following control process: S1, travel control stage: the engine (1) drives the pilot pump (3) to output hydraulic oil to the travel proportional valve (5), the controller (28) generates a PWM signal according to the power distribution parameter input by the intelligent display (27), adjusts the opening ratio of the travel proportional valve (5), and distributes part of the hydraulic oil to the swash plate control servo cylinder of the travel pump A (7) and the travel pump B (9) through the hydraulic control handle valve (6), and the remaining hydraulic oil returns to the oil tank (2) through the first return oil circuit (30); S2, swash plate adjustment stage: the hydraulic control handle valve (6) delivers hydraulic oil to the swash plate control servo cylinders of the travel pump A (7) and the travel pump B (9) according to the operation command, and adjusts the swash plate inclination angles of the travel pump A (7) and the travel pump B (9) synchronously by changing the cylinder stroke, thereby controlling the oil flow and direction of the A circulation oil circuit (14) and the B circulation oil circuit (15); S3, travel execution stage: the hydraulic oil output by the travel pump A (7) and the travel pump B (9) respectively drives the travel motor A (8) and the travel motor B (10) to form a closed loop, and the loader realizes the forward, backward and turning movements through the differential rotation of the travel motor A (8) and the travel motor B (10); S4, attachment independent control stage: when the multi-way valve (16) is not actuated, the first hydraulic oil outputted by the working pump (4) is directly returned to the oil tank (2) via the multi-way valve (16) and the reversing and merging integrated valve (17), and the second hydraulic oil is controlled by the reversing valve of the reversing and merging integrated valve (17) to drive the attachment motor (19) connected to the left attachment quick connector (18); S5, confluence control stage: When the confluence function is activated, the first hydraulic oil of the working pump (4) passes through the multi-way valve (16) and is combined with the second hydraulic oil in the reversing confluence integrated valve (17), and they jointly drive the attachment motor (19), so that the output flow rate is increased to 200% of the independent control stage; S6, accessory coordinated control stage: When the multi-way valve (16) is operated to change direction, the first hydraulic oil drives the accessory cylinder (21) to extend and retract through the right accessory quick connector (20), while the second hydraulic oil maintains an independent control state.

7. The power distribution method for a mini skid steer loader according to claim 6, characterized in that: The activation of the confluence function in step S5 is achieved in the following manner: The intelligent display screen (27) sends a merging instruction to the controller (28); The controller (28) controls the two-position two-way valve in the reversing merging integrated valve (17) to block the direct oil return path, so that the first hydraulic oil and the second hydraulic oil are combined and then output to the left attachment quick connector (18).

8. A mini skid steer loader power distribution method according to claim 6 or 7, characterized in that: The setting of the power allocation parameters includes: In the custom mode, the walking power distribution ratio is set through the intelligent display screen (27) in a graded adjustment range of 20%-100%; In normal mode, the walking power is forcibly locked at 100% rated power; In attachment mode, the travel power is forcibly locked to the preset ratio, and the remaining power is distributed to the dual-control attachment hydraulic system.

9. The power distribution method for a mini skid steer loader according to claim 6, characterized in that: Also includes the power status display process: The controller (28) collects the current signal of the travel proportional valve (5) and the status signal of the reversing and converging integrated valve (17) in real time; The intelligent display screen (27) generates a visual power distribution interface, wherein: Total power is represented by an outline icon; The walking power ratio area dynamically expands or shrinks according to the current allocation ratio; The attachment power ratio area switches from 50% to 100% when confluence is activated, and real-time feedback is provided through changes in the color block area.

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