Device for Fixing an Optical Workpiece for its Processing/Treatment and Method of Fixing an Optical Workpiece on such a Device

Abstract

A device ( 10 ) for retaining a prismatic spectacle lens ( 12 ) at one workpiece surface ( 14 ) for processing of the other workpiece surface ( 16 ) comprises lower and upper parts ( 20, 22 ). The lower part has a base ( 24 ) with a holding interface ( 26 ) and a wedge section ( 28 ). The lower part and upper part are rotatable relative to one another by their mutually facing wedge sections about a rotational axis (DA) inclined with respect to the base axis and retention axis so as to tilt the retaining section and base relative to one another. A wedge orientation arrangement comprises an orientation aid ( 34 ) at the upper part and/or an abutment ( 36 ) between the upper part and lower part, which defines a relative rotational angle end position of the upper part and lower part corresponding with a minimum or maximum tilt of the retaining section with respect to the base.

What is claimed is: 
     
         1 . A device ( 10 ) for retaining an optical workpiece ( 12 ), at a first one of two opposite workpiece surfaces ( 14 ,  16 ) for processing or treating the optical workpiece ( 12 ) at a second one of the workpiece surfaces ( 14 ,  16 ), comprising
 a lower part ( 20 ) with a base ( 24 ), which has a central base axis (BA) and which comprises an interface ( 26 ) for three-dimensionally defined securing to a holder, and a lower wedge section ( 28 ) adjoining the base ( 24 ) along the base axis (BA) and extending transversely to the base axis (BA), and   an upper part ( 22 ) with a retaining section ( 30 ) for the optical workpiece ( 12 ), which has a central retention axis (AA), and an upper wedge section ( 32 ) adjoining the retaining section ( 30 ) along the retention axis (AA) and extending transversely to the retention axis (AA),   wherein the lower part ( 20 ) and the upper part ( 22 ) with the mutually facing lower and upper wedge sections ( 28 ,  32 ) are rotatable relative to one another about a common rotational axis (DA) inclined with respect to the base axis (BA) and the retention axis (AA) so that a relative rotation of the upper part ( 22 ) and lower part ( 20 ) about the rotational axis (DA) produces relative tilting of the retaining section ( 30 ) with respect to the base ( 24 );   characterized by a wedge orientation arrangement with, at the upper part ( 22 ), an orientation aid ( 34 ) by way of which a rotational angle position of the upper part ( 22 ) about the base axis (BA) can be determined and/or the upper part ( 22 ) is fixable in a rotational angle position about the base axis (BA), and/or with an abutment ( 36 ) between the upper part ( 22 ) and the lower part ( 20 ) which defines at least one rotational angle end position of the upper part ( 22 ) with respect to the lower part ( 20 ) about the rotational axis (DA) in which the retaining section ( 30 ) at the upper part ( 22 ) has a minimum or maximum tilt relative to the base ( 24 ) of the lower part ( 20 ).   
     
     
         2 . A device ( 10 ) according to  claim 1 , characterized in that the orientation aid ( 34 ) has a projection ( 50 ) which projects substantially radially outwardly away from the upper wedge section ( 32 ) of the upper part ( 22 ) with respect to the rotational axis (DA), or has in the upper part ( 22 ) a cut-out ( 51 ) extending substantially radially inwardly with respect to the rotational axis (DA). 
     
     
         3 . A device ( 10 ) according to  claim 2 , characterized in that the abutment ( 36 ) has at the lower part ( 20 ) a first abutment section ( 68 ) co-operating with a second abutment section ( 69 ) of the abutment ( 36 ) at the upper part ( 22 ). 
     
     
         4 . A device ( 10 ) according to  claim 3 , characterized in that the first abutment section ( 68 ) and the second abutment section ( 69 ) of the abutment ( 36 ) as seen in a plan view along the rotational axis (DA) are each configured in the form of a ring segment of 90° and as seen in a circumferential direction about the rotational axis (DA) each have two end-face abutment surfaces ( 70 ,  71 ,  72 ,  73 ), wherein one of the abutment surfaces ( 70 ,  71 ) of the first abutment section ( 68 ) co-operates with one of the abutment surfaces ( 72 ,  73 ) of the second abutment section ( 69 ) so as to fix the maximum tilt of the retaining section ( 30 ) at the upper part ( 22 ) relative to the base ( 24 ) of the lower part ( 20 ), whereas another one of the abutment surfaces ( 70 ,  71 ) of the first abutment section ( 68 ) co-operates with another one of the abutment surfaces ( 72 ,  72 ) of the second abutment section ( 69 ) so as to fix the minimum tilt of the retaining section ( 30 ) at the upper part ( 22 ) relative to the base ( 24 ) of the lower part ( 20 ). 
     
     
         5 . A device ( 10 ) according to  claim 4 , characterized in that a relative rotational angle position of the upper part ( 22 ) and lower part ( 20 ) about the rotational axis (DA) is mechanically positively securable in steps. 
     
     
         6 . A device ( 10 ) according to  claim 5 , characterized in that formed between the upper part ( 22 ) and the lower part ( 20 ) is a Hirth toothing ( 74 ) with a first toothing section ( 75 ) on an upper side of the lower part ( 20 ) and a second toothing section ( 76 ), which is formed to be complementary with the first toothing section ( 75 ), on a lower side of the upper part ( 22 ). 
     
     
         7 . A device ( 10 ) according to  claim 6 , characterized in that the Hirth toothing ( 74 ) has a tooth count of between 28 and 36 teeth and/or the individual teeth of the Hirth toothing ( 74 ) have at the radially outer edge of the teeth as referred to the rotational axis (DA) a tooth height of between 1 millimeter and 3 millimeters and/or the individual teeth of the Hirth toothing ( 74 ) lie within a circle about the rotational axis (DA) having a radius of between 15 millimeters and 20 millimeters with respect to the rotational axis (DA). 
     
     
         8 . A device ( 10 ) according to  claim 7 , characterized in that mounted at the retaining section ( 30 ) of the upper part ( 22 ) is a flexible retaining ring ( 60 ) on which the optical workpiece ( 12 ) is placeable by its first workpiece surface ( 14 ). 
     
     
         9 . A device ( 10 ) according to  claim 8 , characterized in that the flexible retaining ring ( 60 )
 is made of NBR or EPDM and/or   has a hardness according to Shore A of between 15 and 80, preferably between 20 and 50, and/or   has a material thickness of between 1.0 millimeter and 8.0 millimeters, preferably between 2.0 millimeters and 5.0 millimeters.   
     
     
         10 . A device ( 10 ) according to  claim 8 , characterized by at the upper part ( 22 ) an outer vacuum chamber ( 38 ) which is bounded at least by an end surface ( 58 ) of the retaining section ( 30 ) at the upper part ( 22 ) and an inner circumferential surface ( 62 ) of the flexible retaining ring ( 60 ) and can be evacuated for releasable holding of the optical workpiece ( 12 ), which is placed on the flexible retaining ring ( 60 ), at the first workpiece surface ( 14 ). 
     
     
         11 . A device ( 10 ) according to  claim 10 , characterized in that the lower part ( 20 ) and the upper part ( 22 ) bound an inner vacuum chamber ( 40 ) which is sealed relative to the environment by a sealing ring ( 64 ) and which can be evacuated in order to releasably hold the upper part ( 22 ) at the lower part ( 20 ) in a predetermined rotational angle setting about the rotational axis (DA). 
     
     
         12 . A device ( 10 ) according to  claim 11 , characterized in that the inner vacuum chamber ( 40 ) is pneumatically connectible or connected with the outer vacuum chamber ( 38 ), the latter preferably by way of a connecting hole ( 66 ) in the retaining section ( 30 ) of the upper part ( 22 ). 
     
     
         13 . A device ( 10 ) according to  claim 12 , characterized in that
 arranged between the lower part ( 20 ) and the upper part ( 22 ) is a spring element ( 82 ) in order to produce between the lower part ( 20 ) and the upper part ( 22 ) a biasing force which urges the lower part ( 20 ) and the upper part ( 22 ) apart, and/or   formed between the lower part ( 20 ) and the upper part ( 22 ) is a detent connection ( 78 ) which secures the upper part ( 20 ) with play to the lower part ( 22 ) against loss, preferably comprising at one part a plurality of flexible detent hooks ( 79 ) which co-operate with an undercut ( 80 ) at the other part, and/or   formed between the lower part ( 20 ) and the upper part ( 22 ) is a centering aid ( 54 ) which aligns the upper part ( 20 ) and the lower part ( 22 ) with respect to the common rotational axis (DA), preferably comprising at one part a substantially hollow-cylindrical sleeve section ( 55 ) co-operating with a substantially cylindrical collar ( 56 ) at the other part.   
     
     
         14 . A device ( 10 ) according to  claim 1 , characterized in that a relative rotational angle position of the upper part ( 22 ) and lower part ( 20 ) about the rotational axis (DA) is mechanically positively securable in steps. 
     
     
         15 . A device ( 10 ) according to  claim 1 , characterized in that mounted at the retaining section ( 30 ) of the upper part ( 22 ) is a flexible retaining ring ( 60 ) on which the optical workpiece ( 12 ) is placeable by its first workpiece surface ( 14 ). 
     
     
         16 . A device ( 10 ) according to  claim 1 , characterized in that the lower part ( 20 ) and the upper part ( 22 ) bound an inner vacuum chamber ( 40 ) which is sealed relative to the environment by a sealing ring ( 64 ) and which can be evacuated in order to releasably hold the upper part ( 22 ) at the lower part ( 20 ) in a predetermined rotational angle setting about the rotational axis (DA). 
     
     
         17 . A device ( 10 ) according to  claim 1 , characterized in that
 arranged between the lower part ( 20 ) and the upper part ( 22 ) is a spring element ( 82 ) in order to produce between the lower part ( 20 ) and the upper part ( 22 ) a biasing force which urges the lower part ( 20 ) and the upper part ( 22 ) apart, and/or   formed between the lower part ( 20 ) and the upper part ( 22 ) is a detent connection ( 78 ) which secures the upper part ( 20 ) with play to the lower part ( 22 ) against loss, preferably comprising at one part a plurality of flexible detent hooks ( 79 ) which co-operate with an undercut ( 80 ) at the other part, and/or   formed between the lower part ( 20 ) and the upper part ( 22 ) is a centering aid ( 54 ) which aligns the upper part ( 20 ) and the lower part ( 22 ) with respect to the common rotational axis (DA), preferably comprising at one part a substantially hollow-cylindrical sleeve section ( 55 ) co-operating with a substantially cylindrical collar ( 56 ) at the other part.   
     
     
         18 . A method for retaining an optical workpiece ( 12 ), particularly a spectacle lens, with a first one of two opposite workpiece surfaces ( 14 ,  16 ) at a retaining device ( 10 ) for processing or treating the optical workpiece ( 12 ) at a second one of the workpiece surfaces ( 14 ,  16 ), comprising the following steps:
 a) providing the optical workpiece ( 12 ) to be processed or treated;   b) providing the retaining device ( 10 ) for the optical workpiece ( 12 ), comprising a lower part ( 20 ) with a base ( 24 ), which has a central base axis (BA) and which comprises an interface ( 26 ) for three-dimensionally defined securing to a holder, and a lower wedge section ( 28 ) adjoining the base ( 24 ) along the base axis (BA) and extending transversely to the base axis (BA), as well as an upper part ( 22 ) with a retaining section ( 30 ), which has a central retention axis (AA), for the optical workpiece ( 12 ) and an upper wedge section ( 32 ) adjoining the retaining section ( 30 ) along the retention axis (AA) and extending transversely to the retention axis (AA), wherein the lower part ( 20 ) and the upper part ( 22 ) by the mutually facing lower and upper wedge sections ( 28 ,  32 ) are rotatable relative to one another about a common rotational axis (DA) which is inclined with respect to the base axis (BA) and the retention axis (AA) so that a relative rotation of the upper part ( 22 ) and lower part ( 20 ) about the rotational axis (DA) produces a relative tilting of the retaining section ( 30 ) with respect to the base ( 24 ), wherein the retaining device ( 10 ) additionally comprises a flexible retaining ring ( 60 ) at the retaining section ( 30 ), an outer vacuum chamber ( 38 ) bounded at least by an end surface ( 58 ) of the retaining section ( 30 ) and an inner circumferential surface ( 62 ) of the flexible retaining ring ( 60 ), and an inner vacuum chamber ( 40 ), which is sealed relative to the environment by a sealing ring ( 64 ), between the lower part ( 20 ) and the upper part ( 22 );   c) ensuring that the desired relative tilting of the retaining section ( 30 ) at the upper part ( 22 ) with respect to the base ( 24 ) of the lower part ( 20 ) is present;   d) placing, with alignment with the retention axis (AA) of the retaining device ( 10 ), the optical workpiece ( 12 ) by its first workpiece surface ( 14 ) on the flexible retaining ring ( 60 ) at the retaining section ( 30 ) of the upper part ( 22 ) of the retaining device ( 10 ); and   e) evacuating the inner vacuum chamber ( 40 ) and the outer vacuum chamber ( 38 ) in common in order at the same time to secure the upper part ( 22 ) and lower part ( 20 ) of the retaining device ( 10 ) to one another in the relative rotational setting thereof about the rotational axis (DA) as well as the optical workpiece ( 12 ) to the retaining section ( 30 ) of the retaining device ( 10 ).   
     
     
         19 . A method according to  claim 18 , wherein
 the step c) of ensuring the desired relative tilting of the retaining section ( 30 ) with respect to the base ( 24 ) comprises relative rotation of the upper part ( 22 ) and lower part ( 20 ) of the retaining device ( 10 ) about the rotational axis (DA); and/or   the step d) of placing the optical workpiece ( 12 ), with alignment with respect to the retention axis (AA) of the retaining device ( 10 ), comprises centering of the optical workpiece ( 12 ) with respect to the retention axis (AA) of the retaining device ( 10 ) and/or a rotational angle orientation of the optical workpiece ( 12 ) about the retention axis (AA) of the retaining device ( 10 ); and/or   at least the step e) is carried out in an evacuable container (BH) into which the retaining device ( 10 ) and the optical workpiece ( 12 ) are inserted; and/or   if the step e) is performed in an evacuable container (BH), a step f) of removal of the retaining device ( 10 ) and the optical workpiece ( 12 ) retained thereat from the evacuable container (BH) follows in which initially the evacuable container (BH) is ventilated, while the optical workpiece ( 12 ) is urged substantially along the retention axis (AA) against the flexible retaining ring ( 60 ).