Positioning apparatus for biomedical use

1. A medical positioning apparatus for positioning and holding an object, comprising:

a telescopic member extending between a first end and a second end and having an adjustable length;

a support member for receiving the object;

a base member securable to a base;

a first joint mechanism movably securing the support member to the first end of the telescopic member;

a second joint mechanism movably securing the base member to the second end of the telescopic member, the first and second joint mechanisms each having at least two rotational degrees of freedom;

a locking device operatively connected to the first and second joint mechanisms and the telescopic member, the locking device operable between a locked position in which the support member, the base member, and the telescopic member are lockingly interconnected together and the length of the telescopic member is fixed, and a released position in which the support and base members are free to pivotally move with respect to the telescopic member and the length of the telescopic member is adjustable, the locking device being passively biased in the locked position, wherein the locking device comprises a first, second, and third locking units operatively connected to the first joint mechanism, the second joint mechanism, and the telescopic member, respectively, and each passively biased in the locked position and wherein each one of the first, second, and third locking units comprises an elastic member, a piston, and a brake pad operatively connected together, the elastic member being passively compressed when the first, second, and third locking units are in the locked position, and being further actively compressed when the first, second, and third locking units are in the released position upon activation of the lock activation device; and

a lock activation device to unlock the locking device biased in the locked position in order to adjust the length of the telescopic member and a relative position of the support member, the base member, and the telescopic member.

2. The medical positioning apparatus of claim 1 , wherein the first and second joint mechanisms each comprise a ball and a socket operatively connected together, the brake pad abutting the ball against the socket for preventing any relative motion between the ball and the socket when the first and second locking units are in the locked position, and the brake pad being away from the ball when the first and second locking units are in the released position.

3. The medical positioning apparatus of claim 2 , wherein the first and second locking units are integrated into the socket of the first and second joint mechanisms, respectively.

4. The medical positioning apparatus of claim 2 , wherein the ball comprises a first and a second hemispherical portions moveably connected together, the first hemispherical portion being fixedly secured to the telescopic member, the piston abutting the second hemispherical portion against the socket for preventing any relative motion between the ball and the socket when the first and second locking units are in the locked position, and the piston being away from the second hemispherical portion when the first and second locking units are in the released position.

5. The medical positioning apparatus of claim 1 , wherein the lock activation device is a pump fluidly connected to the first, second, and third locking units to define a closed-circuit containing a fluid in contact with the piston for the first, second, and third locking units, an activation of the pump causing an increase in a pressure of the fluid for further compressing the elastic member via the piston and unlocking the first, second, and third locking units.

6. The medical positioning apparatus of claim 5 , wherein the pump is a foot pump to be manually operable.

7. The medical positioning apparatus of claim 1 , wherein the telescopic member comprises a first elongated and hollow member and a second elongated member having a given end slidably engaged within the first elongated and hollow member, the third locking unit being secured at the given end of the second elongated member.

8. The medical positioning apparatus of claim 7 , wherein the piston of the third locking unit engages an internal surface of the first elongated and hollow member for fixing the length of the telescopic member when the third locking unit is in the locked position, the piston being away from the internal surface when the third locking unit is in the released position.

9. The medical positioning apparatus of claim 1 , wherein the elastic member is at least one Belleville spring.

10. The medical positioning apparatus of claim 1 , wherein the lock activation device is adapted to substantially concurrently unlock the first, second, and third locking units.

11. The medical positioning apparatus of claim 1 , wherein the lock activation device comprises one of a cable and push/pull rods.

12. The medical positioning apparatus of claim 1 , wherein the support member comprises one of a limb support.

13. The medical positioning apparatus of claim 1 , wherein the support member is a tool holder.

14. The medical positioning apparatus of claim 1 , wherein the base member is securable to one of a bed, a table, and a chair.