Magnetic chucks

• US 3,336,551 A
• Filed: 08/05/1964
• Issued: 08/15/1967
• Est. Priority Date: 08/05/1964
• Status: Expired due to Term

• Current Assignee: Clifford Stead
• Original Assignee: Clifford Stead
• Inventors: Stead, Clifford
• Application Number:
  US04/387,604
• Time in Patent Office: 1,105 Days
• US Class Current: 335/295
• CPC Class Codes: B23Q 3/1546 using permanent magnets

Claims

1. IN A MAGNETIC CHUCK OF THE PERMANENT MAGNET TYPE, COMPRISING (A) A CASING BASE STRUCTURE HAVING A RECESS THEREIN DEFINED BY AN INSIDE BOTTOM WALL AND INSIDE SIDEWALLS, (B) A WORK SUPPORTING FACEPLATE MOUNTED ON SAID BASE STRUCTURE AND COVERING THE RECESS THEREIN WITH SAID FACEPLATE INCLUDING AN ASSEMBLY OF LATERALLY-SPACED POLE PIECES OF PARAMAGNETIC MATERIAL, AND FACEPLATE HAVING AN INNER FACE ARRANGED SUBSTANTIALLY IN A LATTERAL PLANE, (C) A MAGNETIC PACK OF THE PERMANENT MAGNET TYPE RECIPROCATIVELY MOUNTED FOR LATERAL MOVEMENT IN SAID RECESS FREE OF ANY CONTACT WITH ANY OPPOSED PORTIONS OF SAID BOTTOM AND SIDE WALLS DEFINING THE LATTER, WITH SAID PACK INCLUDING AN ASSEMBLY OF LATERALLY-SPACED PERMANENT MAGNETS COOPERATIVELY ARRANGED WITH RESPECT TO SAID FACEPLATE POLE PIECES IN A LATERAL WORK HOLDING POSITION OF SAID PACK WITH SAID PACK HAVING A FACE DISPOSED IN A SUBSTANTIALLY LATERAL PLANE OPPOSED TO SAID INNER FACE OF SAID FACEPLATE FOR LATERAL RECIPROCATION RELATIVE TO THE LATTER, AND (D) MEANS TO RECIPROCATE SAID PACK LATERALLY BETWEEN THE WORK HOLDING POSITION AND ANOTHER POSITION OF WORK RELEASE RELATIVE TO SAID FACEPLATE POLE PIECES;

THE IMPROVEMENT COMPRISING (E) MEANS GUIDING FREE RECIPROCATION OF SAID PACK IN THE BASE STRUCTURE RECESS WHICH ELIMINATES ANY FRICTIONAL SLIDING CONTACT BETWEEN ANY PORTIONS OF AND FIXEDLY MOUNTED ON THE NSIDE BOTTOM AND SIDE WALLS OF THE BASE STRUCTURE RECESS AND OPPOSED PORTIONS OF SAID PACK, AND (F) SLIDE PROMOTING MEANS INTERPOSED BETWEEN SAID FACEPLATE AND PACK OPPOSED FACES SPACING THEM A MINIMUM DISTANCE APART COMPRISING THIN, TOUGH, LONG WEARING DIAMAGNETIC PLASTIC SHEETING OF LOW FRICTION AND HIGH LUBRICITY, WHILE MAGNETIC ATTRACTION BETWEEN SAID FACEPLATE AND PACK MAINTAIN THE OPPOSED FACES OF SAID FACEPLATE AND PACK URGED TOWARD EACH OTHER ON OPPOSITE SIDES OF SAID PLASTIC SHEETING.