| 摘要 |
<p>A directly actuated injection valve comprises a hollow valve housing, a valve needle disposed within the hollow interior, a needle spring, and a magnetostrictive actuator assembly disposed in an annular space around a portion of the valve needle. A magnetic field actuates the magnetostrictive material to change its length to cause a corresponding movement of the valve needle that actuates the valve. The valve needle is comprises of a plurality of magnetostrictive actuator assembly is formed from a non-ferromagnetic material and the portion of the needle comprising the needle tip, which contacts the valve seat, is formed from a different material that has higher through-hardness than that the non-ferromagnetic material. The portion of the needle formed from a non-ferromagnetic material prevents interference with the flux field that is directed through the magnetostrictive member.</p> |
