Single degree of freedom vibration isolating device of linear motor and motion control method thereof

A vibration isolating device of a linear motor for isolating single degree of freedom vibration, which linear motor comprises a rotor (13) and a stator (12), characterized in that, the vibration isolating device comprises a balance block (11) moving along X axis, an anti-drifting driving unit and a control unit;

• the upper surface of the balance block (11) is fixedly connected to the stator (12) of the linear motor, the lower surface of the balance block (11) is connected to the base (1) through a first air bearing (4a), a first grating ruler(2b) is mounted on one side of the balance block (11), the grating stripes of the first grating ruler (2b) are arranged along the direction of X axis, and a first grating ruler reading head (2a) corresponding to the first grating ruler (2b) is mounted on the rotor (13) of the linear motor;
• the anti-drifting driving unit comprises an anti-drifting linear motor, a grating ruler and a guide rail (10);
• the guide rail (10) is fixedly connected to the rotor (9) of the anti-drifting linear motor, one end of the guide rail (10) is connected to the balance block (11) through a second air bearing (4b) in YZ plane, one side of the guide rail (10) in XY plane is connected to the stator (7) of the anti-drifting linear motor through a third air bearing (4c), and one side of the guide rail (10) in XZ plane is connected to the stator (7) of the anti-drifting linear motor through a forth air bearing (4d);
• the stator (7) of the anti-drifting linear motor is fixedly connected to the base (1), a second grating ruler (5b) is mounted on one side of the guide rail (10), the grating stripes of the second grating ruler (5b) are arranged along the direction of X axis, and a second grating ruler reading head (5a) corresponding to the second grating ruler (5b) is mounted on the stator (7) of the anti-drifting linear motor;
• the control unit comprises an industrial personal computer storing a control program, a grating counter card, a DA card and a driver;
• signals of the first grating ruler (2b) and the second grating ruler (5b) are collected and input into the industrial personal computer by the grating counter card, respectively, then the anti-drifting linear motor is controlled by the industrial personal computer by using the signals as position feedback signals, and control instructions are output to the driver through the D/A card.