these magnets into position vertically similarly motor 52 is connected through a reduction gear 518 and a gear output shaft 519 to a magnet clamp 520 that presses against a bearing 521 and that holds a set of sixteen magnets 522 this magnet clamp also has radial outward fingers and shoulders that retain each magnet within the plane of the magnet clamp bolted to this magnet clamp above and below the magnets are a pair of magnet retainer rings that prevent vertical motion of these magnets robot vacuum chamber 54 is enclosed by cylindrical inner wall 55 an outer wall 811 shown in fig8 top wall 523 and bottom wall 524 which are bolted to one another in this particular embodiment walls 524 and 811 are formed as one unitary piece a vacuum seal of chamber 54 is created by vacuum rings 525 and 526 within robot chamber 54 are a set of sixteen magnets 527 retained within the plane of the magnets by a magnet clamp 528 that is similar to clamps 515 and 520 except that the fingers extend radially inward magnet retainer rings above and below the magnets are bolted to clamp 528 to retain these magnets vertically a similar set of magnet clamp 529 and retainer rings hold a set of 16 magnets 530 a set of bearings 531 534 enable clamps 528 and 529 to.