The hydraulic suspension system of a mini tractor can be divided into three types: separate hydraulic system, semi-separate hydraulic system, and integral hydraulic system.
Proper Use of the Operating Devices for a Separate Hydraulic System
When raising the implement, release the lever immediately after moving it to the raised position. Allow the lever to automatically return to the neutral position when the implement reaches its highest raised position.
When lowering the implement or adjusting its height, move the lever to the floating position. The distribution valve will not automatically return to the neutral position when in the floating position.
The forced lowering action is unique to double-acting cylinders and is generally used as a transitional state for implementing the implement into the soil. The forced lowering lever should not be held in the forced lowering position for extended periods; otherwise, forcing the implement to lower will lift the tractor, causing excessive tension on the cylinder lower cover lugs and potentially breaking them.
Generally, the neutral position should not be used for tilling, as this is a disguised position adjustment. It places a significant additional burden on the high-pressure hoses, easily leading to hose damage.
When moving the handle from one position to another, avoid prolonged pauses between the two positions; otherwise, the oil pump may experience overload due to obstructed oil flow.
Proper Use of the Semi-Split Hydraulic System Control Device
The control handles must be used correctly. When using force adjustment for tillage, first place the position adjustment handle in the raised position. The height the implement is raised is determined by the raised position of the position adjustment handle. Use only the force adjustment handle to raise and lower the implement. After selecting a suitable tillage depth through trial plowing, immediately use the positioning handwheel to stop the force adjustment handle to ensure that the handle is pushed to the same position each time, resulting in consistent plowing depth.
When using position adjustment, first place the force adjustment handle in the highest raised position. Use only the position adjustment handle to raise and lower the implement. After selecting the lowering and raising positions of the implement, use the positioning handwheel to position the position adjustment handle accordingly.
When suspending implements for long-distance transport, after raising the implement to the transport position, use the positioning handle to lock it. Also, turn the descent speed adjustment handwheel all the way to the bottom to block the oil cylinder's drain passage. This locks the implement in the transport position, preventing accidents caused by accidental operation of the handle.
When hydraulic transport is not needed, do not move the position adjustment handle to the "hydraulic output" area, as this will cause the safety valve to open frequently, resulting in wear on the oil pump and power loss.
Correct Use of Integrated Hydraulic System Control Devices
An integrated hydraulic system integrates the power, control, and working hydraulic components into a single housing, forming a unified hydraulic system. It does not have a separate oil tank; the working fluid is the gear oil from the rear axle.
Raising and Lowering Implements: With the outer handle of the sector lever fixed in the "shallow-deep" area and the inner handle moved to the "fast" position of the sector lever, the implement will descend quickly. Moving it to the "slow" position will result in a slower descent. When the inner handle is positioned at different locations within the "raise-lower" zone of the sector plate, the implement will be held at corresponding heights above the ground.
When adjusting tillage with force, select the appropriate descent speed within the "fast-slow" zone with the inner handle, and select the desired tillage depth within the "deep-shallow" zone with the outer handle. Afterward, when raising and lowering the plow at the edge of the field, only the inner handle should be used for raising and lowering; the outer handle generally will not be significantly moved.
When adjusting for position, operate the inner handle within the "raise-lower" zone, and place the outer handle in the "deep" position below the sector plate.
When transferring implements between plots while suspended, the inner handle should be at the highest raised position and locked with the positioning handwheel to keep the implement in the transport position. The outer handle should be in the "deep-shallow" zone. Do not pull both handles to the top, as this will put the outer handle in the hydraulic output position, preventing the distribution valve from returning to the neutral position and forcing the safety valve to open.
When using hydraulic output, the inner handle should be selected within the "fast-slow" zone for the descent speed. Pulling the outer handle upwards activates the hydraulic output position. Pushing the handle slightly forward engages the neutral position of the hydraulic cylinder. Pushing the handle further forward initiates the lowering process of the hydraulic cylinder.
When the hydraulic pump is not in use, the eccentric shaft clutch handle should be moved to the "disengaged" position to prevent the pump from idling and causing unnecessary wear on precision parts. When operating the eccentric shaft clutch handle, the clutch must be fully depressed.
