| 摘要 |
A short travel solenoid actuator is disclosed. The solenoid actuator comprises a tube (130), an armature (138) disposed inside the tube, first and second inner pole pieces (139, 140) disposed inside the tube and an outer pole piece (135) which lies outside the tube. The solenoid actuator also comprise an electromagnet coil (133, 134) which lies outside the tube and which is arranged, in response to energisation, to cause travel of the armature between first and second positions. A permanent magnet (136) lies outside the tube and is positioned and orientated so as to latch the armature in the first and second positions when the armature is in the first and second positions respectively. A spring (143) is arranged to bias the armature and is configured to provide sufficient force so as to prevent the armature from latching in second position. |
