| 摘要 |
<p>A pre-tensioning-pre-twisting full-bridge 2D electro-hydraulic proportional directional valve. Two ends of a 2D valve each are connected with a linear electro-mechanical converter (2, 16) through a pressure-torsion coupling and a spring. A cylindrical compression spring (21, 23) is mounted between a valve body (8) and a sliding wedge (20, 25), and the pre-compression amount of the cylindrical compression spring is slightly greater than a stroke of a valve core (9). Left and right sensitive cavities are formed between an end shoulder of the valve core (9), the sliding wedge (20, 25), and the valve body (8). Each end shoulder of the valve core (9) is provided with a pair of high pressure hole and low pressure hole (b and d, c and e), which are respectively communicated with a P opening and a T opening through an inner hole of the valve core. Sensing channels (f and g) are separately formed at two ends of a wall of an inner hole of the valve body (8), and are respectively communicated with the left and right sensitive cavities (h and i). The high pressure hole and the low pressure hole (b and d, c and e) on the end shoulder intersect with the sensing channels to form two tiny openings, and are in series connection with the sensing channels to form hydraulic resistance half bridges. The pressure of the sensitive cavities at the two ends is controlled by the hydraulic resistance half bridges at the two ends respectively. The valve is characterized by large flow and high working pressure.</p> |
