Lens grinding apparatus

Claim 2

A lens grinding apparatus for holding a lens and performing rough and fine grinding operations thereto comprising: a base assembly including rotatable lens holding means; a grinding head assembly including rough and fine grinding wheels thereon, said grinding head assembly movably mounted to said base assembly for alternately positioning one of said grinding wheels in contact with a lens positioned in said holding means; and means for moving said head assembly relative to said base to position one or the other of said grinding wheels into contact with a lens by sequentially raising, shifting, and lowering said grinding wheels relative to said lens holding means and in presettable registration therewith.

Claim 3

The apparatus as defined in claim 1 and further including means for controlling the grinding depth of said grinding wheels in accordance with a preselected pattern comprising: means for rotating a pattern in predetermined relationship with the rotation of said lens; sensing means coupled to said pattern and to said grinding head assembly for detecting the relative position of said grinding head assembly with respect to said lens for a given rotational position of said lens and said pattern; and control means for rotating said lens and said pattern when said sensing means detects that said grinding wheel has removed material from said lens to a depth corresponding to said pattern.

Claim 4

The apparatus as defined in claim 2 wherein said moving means includes a follower member pivotally mounted to said grinding head assembly and releasably clamped thereto and extending toward said base assembly; and transport means movably positioned on said base assembly and including receiving means for releasably holding said follower member such that when said follower is clamped to said grinding head assembly and said transport means is actuated, said transport means moves to carry said follower and said grinding head assembly from a rough grinding to a fine grinding position whereupon said follower is released from said receiving means to lower said grinding head assembly for fine grinding.

Claim 5

The apparatus as defined in claim 3 wherein said transport means includes camming means for moving said follower in a direction to raise said grinding head assembly as said transport means begins to move and wherein said receiving means comprises a member having a tapered open-ended notch to allow said grinding head assembly to gradually lower when said transport means approaches a fine grinding position.

Claim 6

The apparatus as defined in claim 4 and further including an edge follower adjustably positioned on said grinding head assembly for contacting an edge of a lens as said grinding head assembly is transferred to the fine grinding position to prevent further transfer of said grinding head assembly thereby indexing the position of said fine grinding wheel relative to said lens.

Claim 9

The method as defined in claim 6 and including the steps of: sensing the position of the rough grinding wheel in contact with the lens; comparing the position of the rough grinding wheel with the pattern; and rotating the lens pattern when the relative positions reach a first predetermined relationship.

Claim 10

The method as defined in claim 7 including the steps of: sensing the position of the fine grinding wheel in contact with the lens; comparing the position of the fine grinding wheel with the pattern; and rotating the lens and pattern when the relative positions reach a second predetermined relationship.

Claim 11

A lens grinding apparatus comprising: a base assembly including lens holding means for rotatably holding a lens; a grinding head assembly including rough and fine grinding wheels rotatably mounted thereto; means for mounting said head assembly to said base assembly in transversely movable and pivotable relation to said base; means for adjustably positioning said head assembly relative to a lens in said lens holding means for indexing each of said rough and said fine grinding wheels to a lens; transport means coupled between said base assembly and said head assembly for moving said head assembly between a predetermined rough grinding position and a pre-determined fine grinding position; and control means for actuating said transport means.

Claim 12

A lens grinding apparatus comprising: a base assembly including lens holding means for rotatably holding a lens; a grinding head assembly including rough and fine grinding wheels rotatably mounted thereto; means for mounting said head assembly to said base assembly in transversely movable and pivotable relation to said base; means for adjustably positioning said head assembly relative to a lens in said lens holding means for indexing each of said rough and said fine grinding wheels to a lens; transport means coupled between said base assembly and said head assembly for moving said head assembly between a predetermined rough grinding position and a pre-determined fine grinding position; and control means for actuating said transport means.

Claim 13

The apparatus as defined in claim 9 wherein said grinding head assembly includes a follower member extending toward said base assembly and slidably and pivotally positioned on said grinding head assembly and wherein said transport means includes a member slidably positioned on said base assembly and including means for receiving said follower member in releasable engagement therewith.

Claim 14

The apparatus as defined in claim 10 and including means for moving said receiving means in a direction to push against said follower member of said grinding head assembly to tend to pivot said follower member in relation to said grinding head assembly.

Claim 15

The apparatus as defined in claim 11 wherein said grinding head assembly includes braking means for selectively fixing the pivotal position of said following member with respect to said grinding head assembly such that when said receiving means pushes against said follower member, said grinding head assembly pivots with respect to said base assembly.

Claim 16

The apparatus as defined in claim 12 wherein said means for indexing said fine grinding wheel comprises an edge follower adjustably positioned on said grinding head assembly and including a follower shoe extending in spaced relationship from the fine grinding wheel to contact an edge of a lens in said lens holding means thereby limiting the transverse motion of said grinding head assembly when said grinding head assembly moves from roughing to fine grinding positions to position the fine grinding wheel in predetermined relationship to the lens.

Claim 17

The apparatus as defined in claim 13 wherein said means for indexing said rough grinding wheel includes means for adjustably fixing the slidable position of said follower member with respect to said grinding head assembly.

Claim 18

The apparatus as defined in claim 14 wherein said follower shoe is adjustable in a linearly movable path toward and away from said fine grinding wheel.

Claim 19

The apparatus as defined in claim 15 wherein said control means includes timing cam means movable with said lens rotation and having control elements actuated by camming surfaces thereon.

Claim 22

The apparatus as defined in claim 17 wherein said grinding head apparatus is pivotally and slidably mounted to said base assembly to be movable toward and away from a lens held by said lens holding means.

Claim 23

The apparatus as defined in claim 18 wherein said follower member is pivotally mounted to said grinding head assembly and slidably adjustable therewith, and wherein said grinding head assembly includes braking means for fixing the pivotal position of said follower member with respect to said grinding head assembly.

Claim 24

The apparatus as defined in claim 19 wherein said transport means is a housing slidably positioned between guide means to move transversely between rough and fine grinding positions at opposite limits of travel, and wherein said guide means includes camming means for moving said housing in a direction generally orthogonal to its sliding movement as it travels from the rough grinding position.

Claim 25

The apparatus as defined in claim 20 wherein said receiving means comprises an open-ended notched member extending from said housing and having a surface against which said follower member is seated, said surface being tapered away from said follower at the open end of said notch.

Claim 26

The apparatus as defined in claim 21 wherein said apparatus includes stop means positioned on said grinding head assembly and adapted to contact a lens in said lens holder for limiting the transverse motion of said grinding head assembly toward said lens and said control means actuates said braking means and drive means for moving said housing to cause said grinding head assembly to raise, move transversely toward the lens, and lower as the follower slides along said seating surface of said receiving means when said stop means contacts said lens.

Claim 27

A transport assembly for use in shifting the position of a head assembly slidably and pivotally mounted to a base member between first and second predetermined positions comprising: a base member including means for holding an article; a head assembly including means for performing a machining operation on the article held by said base, said assembly transversely slidably, and pivotally mounted to said base member and including transport engaging means extending therefrom; a transport assembly positioned on said base assembly and including a housing with a receiving member adapted to releasably hold said transport engaging means of said head assembly; bias means holding said transport engaging means in contact with said receiving member when said head is in a first position; guide means for loosely supporting said housing in slidable engagement relative to said base member; means for sliding said housing along said guide means; camming means positioned on said base member for moving said housing in a direction to raise said head assembly as said housing assembly moves from an end position corresponding to said first position of said head assembly; and stop means positioned on said head assembly to limit the travel of said head assembly thereby forcing said transport engaging means from said receiving member in a manner to lower said head assembly.

Claim 28

A transport assembly for use in shifting the position of a head assembly slidably and pivotally mounted to a base member between first and second predetermined positions comprising: a base member including means for holding an article; a head assembly including means for performing a machining operation on the article held by said base, said assembly transversely slidably, and pivotally mounted to said base member and including transport engaging means extending therefrom; a transport assembly positioned on said base assembly and including a housing with a receiving member adapted to releasably hold said transport engaging means of said head assembly; bias means holding said transport engaging means in contact with said receiving member when said head is in a first position; guide means for loosely supporting said housing in slidable engagement relative to said base member; means for sliding said housing along said guide means; camming means positioned on said base member for moving said housing in a direction to raise said head assembly as said housing assembly moves from an end position corresponding to said first position of said head assembly; and stop means positioned on said head assembly to limit the travel of said head assembly thereby forcing said transport engaging means from said receiving member in a manner to lower said head assembly.

Claim 29

The apparatus as defined in claim 23 wherein said receiving member is an L-shAped member having a seating surface against which said transport engaging means is positioned, said seating surface being tapered away from said transport engaging means at the open end of said member to gradually lower said head assembly as said transport engaging means slides out of said L-shaped member to said second position.

Claim 30

A lens edge grinding apparatus for shaping a lens blank in accordance with a preselected lens pattern comprising: a base member including means for holding and rotating a lens blank and a lens pattern; a grinding head assembly movably positioned with respect to said base member and including rough and fine grinding wheels rotatably mounted thereto; means for shifting the position of said grinding head assembly to alternately position said rough and fine grinding wheels over said lens blank; a movable follower assembly coupled to said grinding head assembly and having a follower shoe contacting said pattern, said follower assembly including a cam extending therefrom; sensing means positioned on said grinding head assembly and movable between first and second positions, said sensing means including first and second cam surfaces adapted to alternately contact said cam of said follower assembly when said sensing means is in said first or second positions respectively; control means coupled to said sensing means to be selectively actuated by movement of said sensing means for selectively actuating said lens rotating means when the lens blank has been ground by one of said grinding wheels to a predetermined dimension at a peripheral point on the edge of the lens; and additional control means for shifting the grinding head assembly to position the other grinding wheel over the lens blank and to shift the position of the sensing means such that the cam contacts the other of the cam surfaces to actuate said control means to actuate said lens rotating means to remove a different amount of lens material from the lens blank.

Claim 31

A lens edge grinding apparatus for shaping a lens blank in accordance with a preselected lens pattern comprising: a base member including means for holding and rotating a lens blank and a lens pattern; a grinding head assembly movably positioned with respect to said base member and including rough and fine grinding wheels rotatably mounted thereto; means for shifting the position of said grinding head assembly to alternately position said rough and fine grinding wheels over said lens blank; a movable follower assembly coupled to said grinding head assembly and having a follower shoe contacting said pattern, said follower assembly including a cam extending therefrom; sensing means positioned on said grinding head assembly and movable between first and second positions, said sensing means including first and second cam surfaces adapted to alternately contact said cam of said follower assembly when said sensing means is in said first or second positions respectively; control means coupled to said sensing means to be selectively actuated by movement of said sensing means for selectively actuating said lens rotating means when the lens blank has been ground by one of said grinding wheels to a predetermined dimension at a peripheral point on the edge of the lens; and additional control means for shifting the grinding head assembly to position the other grinding wheel over the lens blank and to shift the position of the sensing means such that the cam contacts the other of the cam surfaces to actuate said control means to actuate said lens rotating means to remove a different amount of lens material from the lens blank.

Claim 32

The apparatus as defined in claim 25 wherein said sensing means comprises a plate having an adjustable surface at one end forming said first cam surface and a fixed surface at the same end spaced from said first cam surface, said fixed surface forming said second cam surface, said plate pivotally mounted to said grinding head assembly with said one end extending into contact with said cam of said follower assembly and an opposite end contacting said sensing means.

Claim 33

The apparatus as defined in claim 26 wherein said plate is positioned on a movable shaft of an actuatable cylinder to permit said plate to pivot about the longitudinal axis of said shaft and shift to position a different one of said first or second cam surfaces in contact with said cam when said cylinder is actuated.

Claim 34

A lens grinding apparatus comprising: means for rotatably holding a lens, said holding means including a base assembly having lens holding jaws coupled to a rotatable shaft; means for slidably and pivotally supporting a pair of grinding wheels in relationship to said holding means, said supporting means including a grinding head assembly including bearing means for supporting said assembly on said base in pivotable and slidable relation therewith; transport means including means for releaseably engaging said support means for moving said support means relative to said holding means wherein said grinding head assembly of said supporting means further includes a follower member adapted to extend into releaseable contact with said transport means; and means for disengaging said support means from said transport means when a grinding wheel is positioned in a predetermined relationship to a lens in said holding means.

Claim 35

A lens grinding apparatus comprising: means for rotatably holding a lens, said holding means including a base assembly having lens holding jaws coupled to a rotatable shaft; means for slidably and pivotally supporting a pair of grinding wheels in relationship to said holding means, said supporting means including a grinding head assembly including bearing means for supporting said assembly on said base in pivotable and slidable relation therewith; transport means including means for releaseably engaging said support means for moving said support means relative to said holding means wherein said grinding head assembly of said supporting means further includes a follower member adapted to extend into releaseable contact with said transport means; and means for disengaging said support means from said transport means when a grinding wheel is positioned in a predetermined relationship to a lens in said holding means.

Claim 36

The apparatus as defined in claim 28 wherein said transport means is slidably positioned on said base, and wherein said releaseable engaging means is adapted to receive said follower means extending from said grinding head assembly.

Claim 37

The apparatus As defined in claim 29 wherein said releaseable engaging means comprises a notched member having an open end for allowing said follower to disengage from said notched member at said open end.

Claim 38

The apparatus as defined in claim 30 wherein said disengaging means comprises a stop for limiting the motion of said grinding head assembly thereby forcing said follower out of said notched member when said grinding head assembly has reached a predetermined position relative to a lens within said holding means.

Claim 39

For use in a lens grinding apparatus including a grinding head which has a follower member pivotally attached to the head and extending into releaseable contact with receiving means on a transversely movable transport means positioned on a lens holding base, a method of transferring the grinding head between two lens grinding positions comprising the steps of: locking the follower member in a fixed position relative to said grinding head; moving the transport means from a first position to transversely move the grinding head while simultaneously raising the grinding head by forcing the follower pin in a direction lateral to the transverse movement of the transport means; and limiting the motion of the grinding head to slide the follower member from the receiving means in a manner which allows the grinding head to lower.

Claim 40

For use in a lens grinding apparatus including a grinding head which has a follower member pivotally attached to the head and extending into releaseable contact with receiving means on a transversely movable transport means positioned on a lens holding base, a method of transferring the grinding head between two lens grinding positions comprising the steps of: locking the follower member in a fixed position relative to said grinding head; moving the transport means from a first position to transversely move the grinding head while simultaneously raising the grinding head by forcing the follower pin in a direction lateral to the transverse movement of the transport means; and limiting the motion of the grinding head to slide the follower member from the receiving means in a manner which allows the grinding head to lower.

Claim 41

The method as defined in claim 32 and including the additional steps of: returning the transport means to the first position; raising the grinding head such that the follower member seats in said receiving means; and unlocking said follower member to permit said member to rotate relative to said grinding head.

Claim 42

In a lens grinding apparatus having a grinding head assembly pivotally and slidably positioned on a lens holding base assembly, means for transferring the grinding head assembly to alternately position one of two grinding wheels thereon in alignment with a lens, said means comprising: a transport movably positioned on said base assembly and including receiving means thereon; a sleeve pivotally positioned on said grinding head assembly and including a follower pin extending into releaseable contact with said receiving means; means for actuating said transport means to transversely move said transport and simultaneously shift said grinding head assembly transversely from a first position; cam means coupled to said transport means for forcing said follower pin in a direction which tends to raise said grinding head assembly as said transport means moves from said first position; braking means for locking the pivotal position of said sleeve relative to said grinding head assembly, and control means for actuating said braking means such that said cam means raises said grinding head assembly as said transport means shifts said grinding head assembly.

Claim 43

In a lens grinding apparatus having a grinding head assembly pivotally and slidably positioned on a lens holding base assembly, means for transferring the grinding head assembly to alternately position one of two grinding wheels thereon in alignment with a lens, said means comprising: a transport movably positioned on said base assembly and including receiving means thereon; a sleeve pivotally positioned on said grinding head assembly and including a follower pin extending into releaseable contact with said receiving means; means for actuating said transport means to transversely move said transport and simultaneously shift said grinding head assembly transversely from a first position; cam means coupled to said transport means for forcing said follower pin in a direction which tends to raise said grinding head assembly as said transport means moves from said first position; braking means for locking the pivotal position of said sleeve relative to said grinding head assembly, and control means for actuating said braking means such that said cam means raises said grinding head assembly as said transport means shifts said grinding head assembly.

Claim 44

The apparatus as defined in claim 34 wherein said braking means comprises a shoe assembly rigidly positioned on said grinding head assembly and including a brake shoe movable into contact with said sleeve to fix the relative position of said sleeve and said grinding head assembly when said control means actuates said braking means.