MOOG伺服閥由永磁力矩馬達、噴嘴、檔板、閥芯、閥套和控制腔組成。當輸入線圈通入電流 伺服閥時，檔板向右移動，使右邊噴嘴的節流作用加強，流量減少，右側背壓上升；同時使左邊噴嘴節流作用減小，流量增加，左側背壓下降。閥芯兩端的作用力失去平衡, 閥芯遂向左移動。高壓油從S流向C2，送到負載。負載回油通過 C1流過回油口，進入油箱。閥芯的位移量與力矩馬達的輸入電流成正比，作用在閥芯上的液壓力與彈簧力相平衡，因此在平衡狀態下力矩馬達的差動電流與閥芯的位移成正比。如果輸入的電流反向，則流量也反向。表中是伺服閥的分類。

MOOG 伺服閥 D661-4090  P80HXAF6NSM2O

MOOG 伺服閥 D661-4091 P80HEAF6NSM2O

MOOG 伺服閥 D791-4009

MOOG 伺服閥 D661-4093 P20KAAO6EEM2E

MOOG 伺服閥 D661-4096P60HXAA4NSM2O

MOOG 伺服閥 D661-4097 P80HAAF4VSM2O

MOOG 伺服閥 D661-4098E P80HZCM6NEX2HE

MOOG 伺服閥 D661-4101 P30HAAF4NSX2A

MOOG 伺服閥 D661-4102  P30HAAF6NSF2A

MOOG 伺服閥 D661-4103 P15HXAA5NSM2O

MOOG 伺服閥 D661-4105 P60HDAO6NSM2O

MOOG 伺服閥 D661-4106E P60HAWA5NSM2HO

MOOG 伺服閥 D661-4106E P60HAWA5NSM2HO

MOOG 伺服閥 D661-4107 P60HAAF6NSM2A

MOOG 伺服閥 D791-4009

MOOG 伺服閥 D661-4109 P80HAAA4VSG2A

MOOG 伺服閥 D661-4110P60HAAF6VSM2O

MOOG 伺服閥 D661-4111EP20HAWA4NSM2HO

MOOG 伺服閥 D661-4112 P30HAAF6VSX2B

MOOG 伺服閥 D661-4113 P80HYBF6VSX2B

MOOG 伺服閥 D661-4115 P80HAAO5NS M2A

MOOG 伺服閥 D661-4116E P20HAWA6NSM2HO

MOOG 伺服閥 D661-4117E P20HAWA5NSM2HO

MOOG 伺服閥 D661-4118E P60HAWA6NSM2HO

MOOG 伺服閥 D661-4119E P60HAWA4NSM2HO

MOOG 伺服閥 D661-4120 P80HAAA4NSS2O

MOOG 伺服閥 D661-4121E P30HAWA4NSM2HO

MOOG 伺服閥 D661-4122E P30HAWA5NSM2HO

MOOG 伺服閥 D661-4123E P30HAWA6NSM2HO

MOOG 伺服閥 D661-4127 P80HXAF6NSM2A

MOOG 伺服閥 D661-4128 P60HXAF6NSM2A

MOOG 伺服閥 D661-4160 P80HABB6NSM2O

MOOG 伺服閥 D661-4165 P80HAAM6VS X2A

MOOG 伺服閥 D661-4166 P20HZBF6NSM2O

MOOG 伺服閥 D661-4168 P80HABF6VSX2A

MOOG 伺服閥 D661-4169 P80HAAF6VSM2O

MOOG 伺服閥 D661-4170 P80HABF7VSY2A

MOOG 伺服閥 D661-4172 P80HABF6VSS2B

MOOG 伺服閥 D661-4173 P80HUBD6VSX2B

MOOG 伺服閥 D661-4174 P80HYBD6VSX2B

MOOG 伺服閥 D661-4175 P60HYAD4VSX2A

MOOG 伺服閥 D661-4176 P80JAAF4ESM2O

MOOG 伺服閥 D661-4177 P80HAAF4NSX2A

MOOG 伺服閥D662-4016B

MOOG 伺服閥D662-4307K