Hydraulic Suspension System for Work Vehicle

A hydraulic suspension system comprising:

• a suspension mechanism for a traveling vehicle body;
• a suspension reference position variation mechanism for varying the reference position of the suspension stroke of the suspension mechanism;
• an intermediate value calculator for detecting the maximum position and minimum position of the suspension stroke and calculating an intermediate value between the maximum and minimum positions;
• a cumulating unit for cumulating the frequency at which the intermediate position deviates from a target range as a cumulative frequency;
• a control unit for controlling the operation variation mechanism so that the intermediate position moves in a preset target direction when the cumulative frequency obtained from the cumulating unit exceeds a preset cumulative frequency;
• a stopped state detector (stopped state detection means) for detecting a state in which operation of the suspension mechanism has stopped;
• and
• a control management unit for controlling the suspension reference position variation mechanism so that when the operation of the suspension mechanism is detected to be in a stopped state, the operation of the suspension mechanism moves toward the target range, in preference to control based on the cumulative frequency of the cumulating unit.

A hydraulic suspension system for a work vehicle equipped with an implement, comprising:

• a suspension mechanism for a traveling vehicle body;
• a suspension reference position variation mechanism for varying the reference position of the suspension stroke of the suspension mechanism;
• a suspension stroke position sensor (rising/lowering detection means) for detecting the suspension stroke position;
• a control unit for controlling the suspension reference position variation mechanism on the basis of the suspension stroke position so that the stroke (displacement) of the suspension mechanism moves toward a preset target range;
• an operation detector for detecting an operation for raising or lowering the implement;
• and
• a control management unit for increasing the control frequency of the suspension reference position variation mechanism to be greater than in cases in which the implement is not being raised or lowered, on the basis of raising/lowering operation information generated by the operation detector.

A hydraulic suspension system for a work vehicle equipped with an implement, comprising:

• a suspension mechanism (7) for a traveling vehicle body;
• a suspension reference position variation mechanism for varying the reference position of the suspension stroke of the suspension mechanism;
• an intermediate value calculator for detecting the maximum position and minimum position of the suspension stroke and calculating an intermediate value between the maximum and minimum positions;
• a cumulating unit for cumulating the frequency at which the intermediate position deviates from a target range as a cumulative frequency;
• a control unit for controlling the operation variation mechanism so that the intermediate position moves in a preset target direction when the cumulative frequency obtained from the cumulating unit exceeds a preset cumulative frequency;
• an operation detector for detecting an operation for raising or lowering the implement;
• and
• a control management unit for varying the preset cumulative frequency on the basis of raising/lowering operation information generated by the operation detector so that when an operation of raising or lowering the implement is performed, the preset cumulative frequency decreases from the time the raising/lowering operation is performed until a designated elapsed time has elapsed, and the preset cumulative frequency increases after the designated elapsed time has elapsed since the raising/lowering operation was performed.