Portal system

Portal systems for the multidimensional movement of a holder member in at least x-, y- and z directions to selectable positions within a working space, the portal system comprising:

• (a) a portal having a crossbeam extending in said x-direction with mounting means for mounting said crossbeam at a fixed location;
• (b) a first unit movable along said crossbeam in said x-direction;
• (c) means for moving said first unit in said x-direction;
• (d) a second unit supported by said first unit for movement relative to said first unit in said z-direction;
• and
• (e) means for moving said second unit in said z-direction;
• wherein said second unit comprises:
• (i) a first hollow housing part;
• (ii) a shaft having an axis extending in said z-direction and having a first end and a second end, and being rotatably disposed within said first hollow housing part;
• (iii) a second hollow housing part at said first end of said shaft and rotatable with said shaft about said axis;
• (iv) an axle rotatably disposed in said second housing part and offset to the side of said axis, with said holder member being provided at an end of said axle;
• (v) said holder member being extensible and retractable;
• (vi) a first motor mounted at said first housing part and drivingly connectable to said second end of said shaft;
• (vii) a second motor mounted at said first housing part for driving said axle;
• and
• (viii) a transmission extending from said second motor through said first and second housing parts to said axle for rotation of said axle, whereby movement of said holder member in said y-direction is achieved by rotation of said second housing part about said axis under the influence of said first motor and by rotation of said axle by said second motor.