| 摘要 |
<p>A hydraulic propulsion system for land vehicles comprises a closed hydraulic system (4), in which a pump group (5, 50), a first hydraulic motor (6) for activating wheels (20) of a fixed axle (2) and a second hydraulic motor group (7) for activating wheels (20) of a steering axle (3) are inserted in series. The pump group (5), the first motor group (6) and the second motor group (7) subdivide the hydraulic circuit (4) into an initial tract (40) connecting the pump group (5) to the first motor group (6), an intermediate tract (41) connecting the first motor group (6) to the second motor group (7), and a terminal tract (42) connecting to the second motor group (7) to the pump group (5). The hydraulic circuit (4) comprises at least an auxiliary branch (80, 800) which connects the intermediate tract (41) with either of the initial tract (40) and the final tract (42), and a differential valve (82, 820) for intercepting the auxiliary branch (80, 800), which differential valve (82, 820) is piloted by the difference between the pressures prevailing in two of the tracts (40, 41, 42) of the hydraulic circuit (4).</p> |
