Magnetically suspended and plane-drove vibration isolator

A magnetically suspended and plane-drove vibration isolator with zero stiffness, comprising:

• a upper mounting plate (1),
• a lower mounting plate (2),
• a main body (4) fitted between the upper mounting plate (1) and the lower mounting plate (2), and
• a clean air compressor (3) connected to the main body (4) through an air pipe (26);
• wherein the main body (4) comprising
• a downside-down sleeve (6) lubricated and supported against the lower mounting plate (2) by a magnetically suspended planar motor (24),
• a upside-down piston cylinder (5) fitted in the sleeve (6) and lubricated against the sleeve (6) by a cylindrical air bearing surface (22),
• a spherical air bearing (7) fitted between the piston cylinder (5) and the upper mounting plate (1);
• a voice coil motor in a vertical or Z direction (10) for providing a vertical driving force, a displacement sensor in Z direction (13) and a limit switch in the Z direction (16) having respective sensitive directions along the direction of the vertical driving force that are fitted between the piston cylinder (5) and the sleeve (6);
• a magnetically suspended planar motor (24) for providing a first horizontal driving force and a second horizontal driving force that are perpendicular to each other;
• a displacement sensor in a first horizontal or X direction (11) and a limit switch in the X direction (14) having respective sensitive directions along the direction of the first horizontal driving force that are fitted between a sleeve cylinder (6) and the lower mounting plate (2);
• a displacement sensor in a second horizontal or Y direction (12) and a limit switch in the Y direction (15) having respective sensitive directions along the direction of the second horizontal driving force that are fitted between the sleeve cylinder (6) and the lower mounting plate (2);
• a controller (19) having signal input terminals connected to the displacement sensor in the X direction (11), the displacement sensor in the Y direction (12) and the displacement sensor in the Z direction (13) as well as the limit switch in the X direction (14), the limit switch in the Y direction (15) and the limit switch in the Z direction (16) and signal output terminals;
• and
• a driver (20) having signal input terminals connected to signal output terminals of the controller (19) and signal output terminals connected to the magnetically suspended planar motor (24) and the voice coil motor in the Z direction (10) respectively,
• wherein an air pressure sensor (17) is fitted inside the piston cylinder (5) which is connected to a signal input terminal of the controller (19), and a signal output terminal of the driver (20) is connected to an electromagnetic valve (18) fitted in the piston cylinder (5), and
• wherein the magnetically suspended planar motor (24) is configured as follows:
• the mover of planar motor (24a) is fitted on the bottom of the sleeve (6), the stator of planar motor (24b) is oppositely fitted on the top of the lower mounting plate (2).