| 摘要 |
<p>The invention provides an electrically operated valve which uses a needle valve to open and close a valve port so as to control the flow of a cooling agent, stabilizes the flow of the cooling agent at the valve port and reduces noise by inhibiting vibration of a secondary joint pipe. A first valve port (11) of an inner diameter D1 and a second valve port (12) of an inner diameter D2 with circular cross sections are formed in a valve shell (1). The inner diameter D3 of the secondary joint pipe (22) is arranged to meet D1<D2<D3. The ratio D2/D1 of the inner diameter D2 of the second valve port to the inner diameter D1 of the first valve port is arranged to meet 1.05<=D2/D1<=1.85. The ratio L2/L1 of the length L2 of the second valve port and the length L1 of the first valve port is arranged to meet 20<=L2/L1<=45. A tapered part (13) for connecting the first valve port and the second valve port is formed, the taper angle [alpha 3] of the tapered part is arranged to meet 90 DEG<=[alpha 3]<=150 DEG. Pressure cannot be recovered sharply at the second valve port. The flow of the cooling agent is rectified at the second valve port.</p> |
