Device for Moving a Body Linearly Between Two Predetermined Positions

A device suitable for moving a body along a substantially linear path between a first predetermined position and a second predetermined position, said device comprising:

• a first electromagnet which has a first moving core that is secured to said body and that is arranged to have an axis of action on said body that is substantially parallel to said linear path;
• a second electromagnet which has a second moving core that is secured to said body and that is arranged to have an axis of action on said body that is substantially parallel to said linear path;
• and
• a permanent magnet that is associated functionally with the first core while being disposed in a manner such that it co-operates magnetically and functionally with said first core when the body finds itself in its first position;
• whereby the device is suitable for operating as follows:
• when the body is in the first position, the two electromagnets are not excited and the permanent magnet co-operates magnetically with the first core to lock the body in said first position;
• in order to move the body from its first position to its second position, the first electromagnet is excited in polarized manner so as to generate a magnetic field that is equal and opposite to the field generated by the permanent magnet, the first core of the first electromagnet thus being unlocked, and the second electromagnet is then excited, thereby bringing the body into its second position while driving the first core, the first electromagnet being de-excited as soon as the first core is moved away from the permanent magnet;
• the body is held in said second position so long as the second electromagnet is excited;
• and
• in order to move the body from its second position into said first position, the body is driven from said second position to said first position, while also driving the first core which is brought into magnetic co-operation with the permanent magnet.