CA2249279A1 - Method of mutually positioning a pair of shaping-tool halves facing each other, and shaping tool for the manufacture of precision-made articles, in particular contact lenses - Google Patents
Method of mutually positioning a pair of shaping-tool halves facing each other, and shaping tool for the manufacture of precision-made articles, in particular contact lenses Download PDFInfo
- Publication number
- CA2249279A1 CA2249279A1 CA002249279A CA2249279A CA2249279A1 CA 2249279 A1 CA2249279 A1 CA 2249279A1 CA 002249279 A CA002249279 A CA 002249279A CA 2249279 A CA2249279 A CA 2249279A CA 2249279 A1 CA2249279 A1 CA 2249279A1
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- Canada
- Prior art keywords
- tool
- thermal expansion
- positioning
- mould
- moulding
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/30—Mounting, exchanging or centering
- B29C33/303—Mounting, exchanging or centering centering mould parts or halves, e.g. during mounting
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/56—Coatings, e.g. enameled or galvanised; Releasing, lubricating or separating agents
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D11/00—Producing optical elements, e.g. lenses or prisms
- B29D11/00009—Production of simple or compound lenses
- B29D11/00432—Auxiliary operations, e.g. machines for filling the moulds
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2909/00—Use of inorganic materials not provided for in groups B29K2803/00 - B29K2807/00, as mould material
- B29K2909/08—Glass
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Health & Medical Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Ophthalmology & Optometry (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
- Eyeglasses (AREA)
- Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
- Grinding And Polishing Of Tertiary Curved Surfaces And Surfaces With Complex Shapes (AREA)
Abstract
Proposed is a shaping tool for manufacturing precision-made articles, in particular contact lenses, said shaping tool comprising two halves fitted with inserts (18, 38) and with a cavity (50) between them. The tool is made of ceramic glass with negligible thermal expansion in a given work range. On each side of the cavity (50) is a ceramic-glass insert which defines the shape of the part being manufactured and which is positively held round its circumference in a positioning plate (16, 36) also made of ceramic glass. The positioning plates (16, 36) are each mounted on a ceramic-glass mounting plate (14, 34).
Description
CL,~t-21z~)6/A/CVE 57 pl~ !~ Tlll~ AM{M~LL, Tt~ JEL.~ . ~'1 Method for the reciprocal positioning of pairs of oPposed shape-determining moulding tool portions and a moulding tool for the manufacture of precision articles, esPeciallv contact lenses The invention relates to a method for the reciprocal positioning of pairs of opposed shape-determining moulding tool portions that co-operate to form a mould cavity, for the manufacture of precision articles, especially contact lenses.
The invention relates also to a moulding tool for the manufacture of precision articles, especially contact lenses, that consists of two mould halves having shape-determining tool portions, which mould halves form a mould cavity.
According to the prior art, the moulding tool consists of support plates in each mould half, in each of which support plates a tool insert or a number of tool inserts is/are mounted. The tool inserts of the two mould halves are in alignment with one another and, when the mould is closed, form between them a mould cavity. In known moulding tools for the manufacture of contact lenses, the support plates are made of aluminium. A thin-walled cylindrical clamping bush is installed in a bore in the support plate and is fastened to the support plate by a flange. A sleeve-shaped holder for the tool insert is seated in the clamping bush. The clamping bush forms a pocket into which pressure medium (clamping oil) can be introduced. The wall of the clampingbush is, as a result, deformed and the holder is clamped in place. A centring pin serves to position the clamping bush initially. A number of tool inserts, or tool inserts that have a number of mould cavities for the simultaneous manufacture of a number of contact lenses or the like, can be held in the support plates in the manner described.
The known moulding tools each require a large number of high-precision components.
All the components require complicated surface treatment. The registration of the tool inserts opposed to one another in the two mould halves is difficult and time-consuming, and hence expensive. Component tolerances are cumulative, with the result that precision in the known moulding tools is limited. For that reason, handling of the moulding tools requires great care.
A further important factor is that method steps involving the use of heat are not permitted in the known moulding tools. The linear expansion of the components varies. As a result, changes in temperature will seriously prejudice the alignment. The oil pressure in the hydraulic clamping system also alters under the action of heat.
A problem arises when the mould is opened. The moulded precision articles may beretained by one or other of the mould halves. That depends on random influences that are difficult to control. That uncertainty makes removal of the precision articles difficult, especially when this is to be carried out automatically by a mechanism.
The problem underlying the invention is to construct a moulding tool of the typementioned at the beginning more simply, to simplify alignment and to counteract misalignment.
According to the invention, the problem is solved by a method for the reciprocalpositioning of pairs of opposed shape-determining moulding tool portions that co-operate to form a mould cavity, in which method (a) the position of each of the tool portions is determined by an associated element made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the relative position of the two elements associated with the tool portions is determined precisely by positioning means.
Such materials are known perse. The material may be a glass ceramics material or a specific metal alloy, such as Invar. Quartz glass also exhibits low thermal expansion.
The use of such a material for positioning the shaping tool portions in moulding tools means that the geometry does not change in dependence on the temperature. A toolinsert does not need to be clamped in place hydraulically. The shaping tool portion retains its position relative to the support also in the event of changes in temperature.
The relative position of the supports is again determined directly by high-precision positioning means. It is then possible to use method steps involving the use of heat.
For example, by heating one of the mould halves it is possible to provide distinctly varying adhesion of the moulded precision articles in the mould halves so that the mouldings are all in one mould half after the mould has been opened.
Accordingly, in a moulding tool for the manufacture of precision articles, especially contact lenses, that consists of two mould halves having shape-determining tool portions, which mould halves form a mould cavity, -(a) the position of the shape-determining tool portions in each of the tool halves is determined by supports made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the reciprocal position of the supports is determined by high-precision positioning means that act directly between the two supports.
The dependent claims relate to developments of the invention.
An embodiment of the invention is described in greater detail below with reference to the associated drawings.
Fig. 1 is a diagrammatic representation of two mould halves having tool inserts mounted inside.
Fig. 2 shows diagrammatically the reciprocal positioning of the mould halves.
Fig. 3 is a diagrammatic representation showing a positioning plate in which there are mounted individual tool inserts, each for the manufacture of one contact lens, the positioning plate being positioned relative to the opposed positioningplate in the manner shown in Fig. 2.
Fig. 4 is a diagrammatic representation showing a positioning plate in which there are mounted a plurality of tool inserts, each of which tool inserts is configured for the manufacture of a number of contact lenses or the like, but the positioning plates are positioned relative to one another in the manner shown in Fig.2.
Fig. 5 is a diagrammatic representation showing two tool inserts made of glassceramics, each of which is configured for the manufacture of a plurality of contact lenses and which are mounted without a positioning plate directly on a glass ceramics support plate, the tool inserts themselves being provided with positioning means for positioning relative to their counterpart (not shown).
Fig. 6 shows a moulding tool in which a single glass ceramics plate has recessesor projections for the manufacture of a plurality of contact lenses and has positioning means for positioning the plate relative to the correspondingly constructed counterpart, that plate simultaneously fulfilling the function of support plate, positioning plate and tool insert.
Fig. 7 shows a further embodiment of a moulding tool in which, when the mouldingtool is closed, the support plates are in position relative to one another.
Fig.1 shows an "upper" mould half denoted by the reference numeral 10 and a "lower" mould half denoted by the reference numeral 12. The upper mould half 10 consists of a support plate 14, a positioning plate 16 and a tool insert 18. The tool insert 18 is positioned in an opening 20 of the positioning plate by optical wringing. In the region of the tool insert 18, the support plate 14 has a bore 22. An annularprojection 24 having a polished end face 26 is formed around the bore on the surface of the support plate that faces the tool insert 18. The likewise polished rear face 28 of the tool insert 18 rests against the end face 26. The rear face 28 is joined to the end face 26 by optical wringing. The front face 30 of the tool insert 18 is provided with a recess and defines a mould cavity 32. The positioning plate 16 is joined to the support plate 14.
The tool insert in this case forms a "shape-determining tool portion".
The "lower" mould half 12 is of similar construction to the mould half 10. The lower mould half 12 consists of a support plate 34, a positioning plate 36 and a tool insert 38. The tool insert 38 is positioned in an opening 40 in the positioning plate 36 by wringing. In the region of the tool insert 38, the support plate 34 has a bore 42. An annular projection 44 having a polished end face 46 is formed around the bore 42 on the surface of the support plate that faces the tool insert 38. The likewise polished rear face 48 of the tool insert 38 rests against the end face 46. The rear face 48 is joined to the end face 46 also by optical wringing. The front face 50 of the tool insert 38 is provided with a convexity and defines the mould cavity 32 on the side which, in Fig.1, is the lower side. The positioning plate 36 is joined to the support plate 34.
The support plates 14 and 34, the positioning plates 16 and 36 and the tool inserts 18 and 38 are all made of a material having negligible thermal expansion in the working range of the moulding tool.
That material is preferably a non-transparent glass ceramics material. It is also possible, however, to use a metal alloy, such as Invar. The tool inserts are preferably made of a transparent material (or one of the tool inserts is made of a transparent material and the other is made of an absorbent, and hence non-transparent, material), with the result that the moulded product, for example a contact lens, can be treated with light inside the mould. Quartz glass, which also exhibits very low thermal expansion, has proved suitable for that purpose. The light beam is delimited sharply by the wall of the bores 22 and 42 since the material of the support plates 14 and 34 and that of the positioning plates 16 and 36 is non-transparent. Consequently, the contact lenses can be manufactured with very precise edges.
The support plates 14 and 34 are joined to the associated positioning plates 16 and 36 also by optical wringing. Alternatively, however, a different method of fastening can be used.
Fig. 2 shows positioning means that provide precise alignment of the positioningplates 16 and 36 relative to one another. A bore 52 is provided in the positioning plate 36. An index pin 54 is seated snugly in that bore 52. A bore 56 is provided in the positioning piate 16. An index bush 58 is also seated snugly in the bore 56. When the mould is closed, the index pin 54 is guided with low tolerances in the index bush 58.
The index pin 54 tapers at one end 60 so that it can be inserted easily into the index bush 58. In the region of the index pin 58, the support plate 14 has a bore 61 into which the end of the index pin 54 projects in the closed state.
Opening and closing of the moulding tool is performed using a known mechanism not shown. It is important that the mechanism allows a small amount of lateral play of the support plates 14 and 34 and the positioning plates 16 and 36 relative to one another, .
so that the position relative to one another of the positioning plates and thus of the tool inserts 18 and 38 can be determined exclusively by the positioning means (Fig. 2) mounted on the positioning plates 16 and 36.
Fig. 3 is a diagrammatic representation of a moulding portion of a moulding tool of the kind shown in Figs.1 and 2 having a plurality of tool inserts 38. Each of the tool inserts 38 is configured for the manufacture of a single contact lens (or some other precision article). Those tool inserts 38 are then mounted in rows and columns of openings 40 (Fig.1) in the positioning plate 36. Two index pins 54 of the kind shown in Fig. 2 are located in the corners of the positioning plate 36.
Fig. 4 is a modified development of a mould half. The positioning plate 36 in this case has a number of, for example rectangular, openings 62. Seated in the openings 62are corresponding tool inserts 64, each of which has a plurality of recesses or convexities for the manufacture of a plurality of contact lenses. Here too the positioning plate 36 is centred relative to its counterpart by index pins 54.
In this case also, all the parts are made of a material such as a glass ceramicsmaterial having thermal expansion that is negligible in a working range.
Fig. 5 shows an arrangement in which two tool inserts 68 and 70 of glass ceramics are mounted directly on a support plate 66. Each of those tool inserts 68 and 70 is configured for the manufacture of a plurality of precision articles, such as contact lenses, and has corresponding recesses or convexities 72. Each of the tool inserts 68 CA 02249279 l998-09-l7 and 70 can be centred relative to its counterpart by pairs of index pins or index bushes 74,76 and 78,80, respectively, in a manner similar to that described in the context of Fig. 2. There are no positioning plates in this solution.
In the development according to Fig. 6, only a plate 82 of glass ceramics or the like is provided as tool half. The plate 82 has rows and columns of recesses or convexities 84 for the simultaneous moulding of a plurality of contact lenses. The plate 82 can be centred precisely relative to a corresponding counterpart by positioning means 86,88.
In this case there is neither a separate support plate nor a positioning plate. Instead, the shape of the contact lenses is determined by the recesses or convexities 84 on the plate 82 that forms the tool half.
Fig. 7 shows a further development of a moulding tool. The upper portion of the moulding tool is denoted by the reference numeral 90. The lower portion of the moulding tool is denoted by the reference numeral 92. The upper portion 90 comprises a support plate 94 and a tool insert 96. Fig. 7iS a fragmentary representation. Generally, a plurality of tool inserts 96 will be mounted on a support plate 94. The lower portion 92 comprises a support plate 98 and a tool insert 100. The two tool inserts 96 and 100 form the "shape-determining tool portions" and define a mould cavity 106 by means of a convex surface 102 and a recess 104. The support plates 94 and 98 are made of glass ceramics having negligible thermal expansion.The surfaces of the support plates 94 and 98 that face one another are polished.
The tool inserts 96 and 100 are each seated in bores in the positioning plates 110 and 112, respectively. The positioning plates are also made of glass ceramics or some other material having negligible thermal expansion.
Positioning means in the form of an index pin 114 and index bushes 116,118 and 120 provide for precise positioning relative to one another not only of the positioning plates 110 and 112 but also of the support plates 94 and 98. For that purpose, the index pin 1 14is seated in a bore 122 in the support plate 98. The index bush 116is seated in a bore 124 in the other support plate 94. The other index bushes 118 and 120 are seated in bores 126 and 128, respectively, of the positioning plates 110 and 112, respectiveiy. All the index bushes 116,118 and 120 are guided on the index pin Bores 130 and 132, which are in alignment with the tool inserts 96 and 100, are provided in the support plates 94 and 98, respectively.
The support plates 94 and 98 and the positioning plates 110 and 112 are aligned precisely with one another by the index pins 114 and index bushes 116,118 and 120.
That also ensures precise alignment of the tool inserts 96 and 100 that are held in the positioning plates 110 and 112, both with one another and with the support plates 94 and 98. Those positions are to a very great extent independent of the temperature. In those positions, the tool inserts 96 and 100, which have polished rear faces 134 and 136, respectively, are attached to the polished surfaces of the support plates 94 and 98, respectively, by optical wringing.
After being attached by wringing, it is possible for the positioning plates 110 and 112 to be removed again so that the mould halves 90 and 92 are formed only by the support plates 94 and 98 and the tool inserts 96 and 100 that have been attachedthereto by optical wringing. For that reason, in Fig. 7 the positioning plates 110 and 112 are indicated by broken lines.
,_ It is, of course, also possible to leave the positioning plates 110 and 112 in the moulding tool and to join them to the support plates 94 and 98, for example also by optical wringing.
The invention relates also to a moulding tool for the manufacture of precision articles, especially contact lenses, that consists of two mould halves having shape-determining tool portions, which mould halves form a mould cavity.
According to the prior art, the moulding tool consists of support plates in each mould half, in each of which support plates a tool insert or a number of tool inserts is/are mounted. The tool inserts of the two mould halves are in alignment with one another and, when the mould is closed, form between them a mould cavity. In known moulding tools for the manufacture of contact lenses, the support plates are made of aluminium. A thin-walled cylindrical clamping bush is installed in a bore in the support plate and is fastened to the support plate by a flange. A sleeve-shaped holder for the tool insert is seated in the clamping bush. The clamping bush forms a pocket into which pressure medium (clamping oil) can be introduced. The wall of the clampingbush is, as a result, deformed and the holder is clamped in place. A centring pin serves to position the clamping bush initially. A number of tool inserts, or tool inserts that have a number of mould cavities for the simultaneous manufacture of a number of contact lenses or the like, can be held in the support plates in the manner described.
The known moulding tools each require a large number of high-precision components.
All the components require complicated surface treatment. The registration of the tool inserts opposed to one another in the two mould halves is difficult and time-consuming, and hence expensive. Component tolerances are cumulative, with the result that precision in the known moulding tools is limited. For that reason, handling of the moulding tools requires great care.
A further important factor is that method steps involving the use of heat are not permitted in the known moulding tools. The linear expansion of the components varies. As a result, changes in temperature will seriously prejudice the alignment. The oil pressure in the hydraulic clamping system also alters under the action of heat.
A problem arises when the mould is opened. The moulded precision articles may beretained by one or other of the mould halves. That depends on random influences that are difficult to control. That uncertainty makes removal of the precision articles difficult, especially when this is to be carried out automatically by a mechanism.
The problem underlying the invention is to construct a moulding tool of the typementioned at the beginning more simply, to simplify alignment and to counteract misalignment.
According to the invention, the problem is solved by a method for the reciprocalpositioning of pairs of opposed shape-determining moulding tool portions that co-operate to form a mould cavity, in which method (a) the position of each of the tool portions is determined by an associated element made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the relative position of the two elements associated with the tool portions is determined precisely by positioning means.
Such materials are known perse. The material may be a glass ceramics material or a specific metal alloy, such as Invar. Quartz glass also exhibits low thermal expansion.
The use of such a material for positioning the shaping tool portions in moulding tools means that the geometry does not change in dependence on the temperature. A toolinsert does not need to be clamped in place hydraulically. The shaping tool portion retains its position relative to the support also in the event of changes in temperature.
The relative position of the supports is again determined directly by high-precision positioning means. It is then possible to use method steps involving the use of heat.
For example, by heating one of the mould halves it is possible to provide distinctly varying adhesion of the moulded precision articles in the mould halves so that the mouldings are all in one mould half after the mould has been opened.
Accordingly, in a moulding tool for the manufacture of precision articles, especially contact lenses, that consists of two mould halves having shape-determining tool portions, which mould halves form a mould cavity, -(a) the position of the shape-determining tool portions in each of the tool halves is determined by supports made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the reciprocal position of the supports is determined by high-precision positioning means that act directly between the two supports.
The dependent claims relate to developments of the invention.
An embodiment of the invention is described in greater detail below with reference to the associated drawings.
Fig. 1 is a diagrammatic representation of two mould halves having tool inserts mounted inside.
Fig. 2 shows diagrammatically the reciprocal positioning of the mould halves.
Fig. 3 is a diagrammatic representation showing a positioning plate in which there are mounted individual tool inserts, each for the manufacture of one contact lens, the positioning plate being positioned relative to the opposed positioningplate in the manner shown in Fig. 2.
Fig. 4 is a diagrammatic representation showing a positioning plate in which there are mounted a plurality of tool inserts, each of which tool inserts is configured for the manufacture of a number of contact lenses or the like, but the positioning plates are positioned relative to one another in the manner shown in Fig.2.
Fig. 5 is a diagrammatic representation showing two tool inserts made of glassceramics, each of which is configured for the manufacture of a plurality of contact lenses and which are mounted without a positioning plate directly on a glass ceramics support plate, the tool inserts themselves being provided with positioning means for positioning relative to their counterpart (not shown).
Fig. 6 shows a moulding tool in which a single glass ceramics plate has recessesor projections for the manufacture of a plurality of contact lenses and has positioning means for positioning the plate relative to the correspondingly constructed counterpart, that plate simultaneously fulfilling the function of support plate, positioning plate and tool insert.
Fig. 7 shows a further embodiment of a moulding tool in which, when the mouldingtool is closed, the support plates are in position relative to one another.
Fig.1 shows an "upper" mould half denoted by the reference numeral 10 and a "lower" mould half denoted by the reference numeral 12. The upper mould half 10 consists of a support plate 14, a positioning plate 16 and a tool insert 18. The tool insert 18 is positioned in an opening 20 of the positioning plate by optical wringing. In the region of the tool insert 18, the support plate 14 has a bore 22. An annularprojection 24 having a polished end face 26 is formed around the bore on the surface of the support plate that faces the tool insert 18. The likewise polished rear face 28 of the tool insert 18 rests against the end face 26. The rear face 28 is joined to the end face 26 by optical wringing. The front face 30 of the tool insert 18 is provided with a recess and defines a mould cavity 32. The positioning plate 16 is joined to the support plate 14.
The tool insert in this case forms a "shape-determining tool portion".
The "lower" mould half 12 is of similar construction to the mould half 10. The lower mould half 12 consists of a support plate 34, a positioning plate 36 and a tool insert 38. The tool insert 38 is positioned in an opening 40 in the positioning plate 36 by wringing. In the region of the tool insert 38, the support plate 34 has a bore 42. An annular projection 44 having a polished end face 46 is formed around the bore 42 on the surface of the support plate that faces the tool insert 38. The likewise polished rear face 48 of the tool insert 38 rests against the end face 46. The rear face 48 is joined to the end face 46 also by optical wringing. The front face 50 of the tool insert 38 is provided with a convexity and defines the mould cavity 32 on the side which, in Fig.1, is the lower side. The positioning plate 36 is joined to the support plate 34.
The support plates 14 and 34, the positioning plates 16 and 36 and the tool inserts 18 and 38 are all made of a material having negligible thermal expansion in the working range of the moulding tool.
That material is preferably a non-transparent glass ceramics material. It is also possible, however, to use a metal alloy, such as Invar. The tool inserts are preferably made of a transparent material (or one of the tool inserts is made of a transparent material and the other is made of an absorbent, and hence non-transparent, material), with the result that the moulded product, for example a contact lens, can be treated with light inside the mould. Quartz glass, which also exhibits very low thermal expansion, has proved suitable for that purpose. The light beam is delimited sharply by the wall of the bores 22 and 42 since the material of the support plates 14 and 34 and that of the positioning plates 16 and 36 is non-transparent. Consequently, the contact lenses can be manufactured with very precise edges.
The support plates 14 and 34 are joined to the associated positioning plates 16 and 36 also by optical wringing. Alternatively, however, a different method of fastening can be used.
Fig. 2 shows positioning means that provide precise alignment of the positioningplates 16 and 36 relative to one another. A bore 52 is provided in the positioning plate 36. An index pin 54 is seated snugly in that bore 52. A bore 56 is provided in the positioning piate 16. An index bush 58 is also seated snugly in the bore 56. When the mould is closed, the index pin 54 is guided with low tolerances in the index bush 58.
The index pin 54 tapers at one end 60 so that it can be inserted easily into the index bush 58. In the region of the index pin 58, the support plate 14 has a bore 61 into which the end of the index pin 54 projects in the closed state.
Opening and closing of the moulding tool is performed using a known mechanism not shown. It is important that the mechanism allows a small amount of lateral play of the support plates 14 and 34 and the positioning plates 16 and 36 relative to one another, .
so that the position relative to one another of the positioning plates and thus of the tool inserts 18 and 38 can be determined exclusively by the positioning means (Fig. 2) mounted on the positioning plates 16 and 36.
Fig. 3 is a diagrammatic representation of a moulding portion of a moulding tool of the kind shown in Figs.1 and 2 having a plurality of tool inserts 38. Each of the tool inserts 38 is configured for the manufacture of a single contact lens (or some other precision article). Those tool inserts 38 are then mounted in rows and columns of openings 40 (Fig.1) in the positioning plate 36. Two index pins 54 of the kind shown in Fig. 2 are located in the corners of the positioning plate 36.
Fig. 4 is a modified development of a mould half. The positioning plate 36 in this case has a number of, for example rectangular, openings 62. Seated in the openings 62are corresponding tool inserts 64, each of which has a plurality of recesses or convexities for the manufacture of a plurality of contact lenses. Here too the positioning plate 36 is centred relative to its counterpart by index pins 54.
In this case also, all the parts are made of a material such as a glass ceramicsmaterial having thermal expansion that is negligible in a working range.
Fig. 5 shows an arrangement in which two tool inserts 68 and 70 of glass ceramics are mounted directly on a support plate 66. Each of those tool inserts 68 and 70 is configured for the manufacture of a plurality of precision articles, such as contact lenses, and has corresponding recesses or convexities 72. Each of the tool inserts 68 CA 02249279 l998-09-l7 and 70 can be centred relative to its counterpart by pairs of index pins or index bushes 74,76 and 78,80, respectively, in a manner similar to that described in the context of Fig. 2. There are no positioning plates in this solution.
In the development according to Fig. 6, only a plate 82 of glass ceramics or the like is provided as tool half. The plate 82 has rows and columns of recesses or convexities 84 for the simultaneous moulding of a plurality of contact lenses. The plate 82 can be centred precisely relative to a corresponding counterpart by positioning means 86,88.
In this case there is neither a separate support plate nor a positioning plate. Instead, the shape of the contact lenses is determined by the recesses or convexities 84 on the plate 82 that forms the tool half.
Fig. 7 shows a further development of a moulding tool. The upper portion of the moulding tool is denoted by the reference numeral 90. The lower portion of the moulding tool is denoted by the reference numeral 92. The upper portion 90 comprises a support plate 94 and a tool insert 96. Fig. 7iS a fragmentary representation. Generally, a plurality of tool inserts 96 will be mounted on a support plate 94. The lower portion 92 comprises a support plate 98 and a tool insert 100. The two tool inserts 96 and 100 form the "shape-determining tool portions" and define a mould cavity 106 by means of a convex surface 102 and a recess 104. The support plates 94 and 98 are made of glass ceramics having negligible thermal expansion.The surfaces of the support plates 94 and 98 that face one another are polished.
The tool inserts 96 and 100 are each seated in bores in the positioning plates 110 and 112, respectively. The positioning plates are also made of glass ceramics or some other material having negligible thermal expansion.
Positioning means in the form of an index pin 114 and index bushes 116,118 and 120 provide for precise positioning relative to one another not only of the positioning plates 110 and 112 but also of the support plates 94 and 98. For that purpose, the index pin 1 14is seated in a bore 122 in the support plate 98. The index bush 116is seated in a bore 124 in the other support plate 94. The other index bushes 118 and 120 are seated in bores 126 and 128, respectively, of the positioning plates 110 and 112, respectiveiy. All the index bushes 116,118 and 120 are guided on the index pin Bores 130 and 132, which are in alignment with the tool inserts 96 and 100, are provided in the support plates 94 and 98, respectively.
The support plates 94 and 98 and the positioning plates 110 and 112 are aligned precisely with one another by the index pins 114 and index bushes 116,118 and 120.
That also ensures precise alignment of the tool inserts 96 and 100 that are held in the positioning plates 110 and 112, both with one another and with the support plates 94 and 98. Those positions are to a very great extent independent of the temperature. In those positions, the tool inserts 96 and 100, which have polished rear faces 134 and 136, respectively, are attached to the polished surfaces of the support plates 94 and 98, respectively, by optical wringing.
After being attached by wringing, it is possible for the positioning plates 110 and 112 to be removed again so that the mould halves 90 and 92 are formed only by the support plates 94 and 98 and the tool inserts 96 and 100 that have been attachedthereto by optical wringing. For that reason, in Fig. 7 the positioning plates 110 and 112 are indicated by broken lines.
,_ It is, of course, also possible to leave the positioning plates 110 and 112 in the moulding tool and to join them to the support plates 94 and 98, for example also by optical wringing.
Claims (25)
1. A method for the reciprocal positioning of pairs of opposed shape-determiningmoulding tool portions that co-operate to form a mould cavity, for the manufacture of precision articles, especially contact lenses, in which method (a) the position of each of the tool portions is determined by an associated element made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the relative position of the two elements associated with the tool portions is determined precisely by positioning means.
2. A method according to claim 1, in which (a) the tool portions are each fixed, in the resulting positions, to a support made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the positioning element is subsequently removed.
3. A method according to claim 1 or claim 2, in which (a) the tool portions and, where appropriate, the supports are provided with polished flat surfaces, and (b) the fixing of the tool portions is effected by optical wringing.
4. A method according to any one of claims 1 to 3, in which a glass ceramics material is used as material that exhibits negligible thermal expansion in a working temperature range.
5. A method according to any one of claims 1 to 3, in which a metal alloy having low thermal expansion, for example Invar, is used as material that exhibits negligible thermal expansion in a working temperature range.
6. A method according to any one of claims 1 to 5, in which a quartz glass is used as material for the tool portion.
7. A moulding tool for the manufacture of precision articles, especially contact lenses, that consists of two tool halves (10,12; 90, 92) having shape-determining tool portions (18, 38; 96, 100), which tool halves form a mould cavity (32; 106), in which moulding tool (a) the position of the shape-determining tool portions (18, 38; 96, 100) in each of the tool halves (10,12; 90, 92) is determined by supports (16, 36; 94, 98) made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) the reciprocal position of the supports (16, 36; 94, 98) is determined by high-precision positioning means (54, 58; 114, 116) that act directly between the two supports (16, 36; 94, 98).
8. A moulding tool according to claim 7, in which the tool inserts (18, 38; 96, 100) are each mounted on a support plate (14, 34; 94, 98) made of a material that exhibits negligible thermal expansion in a working temperature range.
9. A moulding tool according to either claim 7 or claim 8, in which there is provided on each side of the mould cavity (32) a tool insert (18, 38; 96, 98) that determines the shape of the precision article to be manufactured, which tool insert is held around its circumference in a form fit in a positioning plate (16, 36; 110,112) made of a material that exhibits negligible thermal expansion in a working temperature range.
10. A moulding tool according to any one of claims 7 to 9, in which the positioning means comprise index pins (54; 114).
11. A moulding tool according to claim 9, in which the positioning plates (16, 36) are held in a precisely defined position relative to one another by the positioning means (54, 58).
12. A moulding tool according to claim 10, in which (a) index pins (54) are mounted on one of the positioning plates (36), and (b) the other positioning plate (16) has, in alignment with each index pin (54), an opening (56) having an index bush (58), the tool inserts (18, 38) opposed to one another being in correct alignment with one another when the index pins (54) engage in the index bushes (58).
13. A moulding tool according to claim 10, in which (a) index pins (114) are mounted on one of the support plates (98), and (b) the other support plate (94) has, in alignment with each index pin (114), anopening (124) having an index bush (116), the tool inserts (96, 100) opposed to one another being in correct alignment with one another when the index pins (114) engage in the index bushes (116).
14. A moulding tool according to claim 13, in which (a) the tool inserts (96, 100) are held in openings in positioning plates (110, 112), (b) the positioning plates (110, 112) are guided with index bushes (118, 120) on the index pins (114) that position the support plates (94, 98) relative to one another and are thus positioned relative to one another and to the support plates (94, 98), and (c) the positioning plates (110, 112) are joined to the support plates (94, 98) by optical wringing.
15. A moulding tool according to any one of claims 8 to 14, in which each support plate (14, 34; 94, 98) forms a stop (24, 44) against which the tool insert (18, 38; 96, 100) rests in the direction perpendicular to the support plate (14, 34; 94, 98).
16. A moulding tool according to claim 15, in which the tool insert (18, 38; 96, 100) is joined to the support plate (14, 34; 94, 98) by optical wringing.
17. A moulding tool according to any one of claims 7 to 16, in which guide means for guiding the mould halves to the closed position allow a small amount of lateral movement of the mould halves so that alignment can be effected solely in accordance with the positioning means (54, 58) of the supports (16, 36).
18. A moulding tool according to claim 8, in which each of the tool inserts (62) has a plurality of mould-cavity-defining surfaces for the simultaneous manufacture of a number of precision articles to be moulded.
19. A moulding tool according to claim 7, in which in each mould half (a) there is mounted on a support plate (66) a plurality of tool inserts (68, 70) that are made of a material that exhibits negligible thermal expansion in a working temperature range, and (b) each of the tool inserts (68, 70) is positioned individually relative to itscounterpart on the other mould half by positioning means (74, 76; 78, 80).
20. A moulding tool according to claim 19, in which each of the tool inserts (68, 70) has a plurality of mould-cavity-defining surfaces for the simultaneous manufacture of a number of precision articles to be moulded.
21. A moulding tool according to claim 7, in which (a) each of the mould halves has a single plate (82) made of a material that exhibits negligible thermal expansion in a working temperature range, in which plate there are formed a plurality of mould-cavity-defining surfaces (84) for the simultaneous manufacture of a number of precision articles to be moulded, and (b) that plate (82) is positioned relative to its counterpart in the other mould half by centring means (86, 88).
22. A moulding tool according to any one of claims 7 to 20, in which a glass ceramics material is provided as material that exhibits negligible thermal expansion in a working temperature range.
23. A moulding tool according to any one of claims 7 to 20, in which a quartz glass is provided as material that exhibits negligible thermal expansion in a working temperature range.
24. A moulding tool according to claim 23, in which mould inserts provided as shape-determining tool portions consist of quartz glass.
25. A moulding tool according to any one of claims 7 to 20, in which a metal alloy having low thermal expansion, for example Invar, is provided as material that exhibits negligible thermal expansion in a working temperature range.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19610563A DE19610563A1 (en) | 1996-03-18 | 1996-03-18 | Method for the mutual positioning of pairs of opposing shape-determining mold parts and mold for the production of precision parts, in particular contact lenses |
| DE19610563.3 | 1996-03-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2249279A1 true CA2249279A1 (en) | 1997-09-25 |
Family
ID=7788611
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002249279A Abandoned CA2249279A1 (en) | 1996-03-18 | 1997-03-05 | Method of mutually positioning a pair of shaping-tool halves facing each other, and shaping tool for the manufacture of precision-made articles, in particular contact lenses |
Country Status (11)
| Country | Link |
|---|---|
| EP (1) | EP0891246B1 (en) |
| JP (1) | JP2000506463A (en) |
| KR (1) | KR20000064606A (en) |
| CN (1) | CN1214005A (en) |
| AT (1) | ATE202967T1 (en) |
| AU (1) | AU715356B2 (en) |
| BR (1) | BR9708095A (en) |
| CA (1) | CA2249279A1 (en) |
| DE (2) | DE19610563A1 (en) |
| IL (1) | IL126061A0 (en) |
| WO (1) | WO1997034752A1 (en) |
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| US5989462A (en) | 1997-07-31 | 1999-11-23 | Q2100, Inc. | Method and composition for producing ultraviolent blocking lenses |
| TW429327B (en) * | 1997-10-21 | 2001-04-11 | Novartis Ag | Single mould alignment |
| DE59903705D1 (en) | 1998-03-10 | 2003-01-23 | Novartis Ag | Molding tool for the production of precision parts, in particular contact lenses |
| EP0941829B1 (en) * | 1998-03-10 | 2002-12-11 | Novartis AG | Mould for making precision parts especially contact lenses |
| US6419873B1 (en) | 1999-03-19 | 2002-07-16 | Q2100, Inc. | Plastic lens systems, compositions, and methods |
| US6528955B1 (en) | 2000-03-30 | 2003-03-04 | Q2100, Inc. | Ballast system for a fluorescent lamp |
| US6698708B1 (en) | 2000-03-30 | 2004-03-02 | Q2100, Inc. | Gasket and mold assembly for producing plastic lenses |
| US6723260B1 (en) | 2000-03-30 | 2004-04-20 | Q2100, Inc. | Method for marking a plastic eyeglass lens using a mold assembly holder |
| US6716375B1 (en) | 2000-03-30 | 2004-04-06 | Q2100, Inc. | Apparatus and method for heating a polymerizable composition |
| WO2001074572A2 (en) * | 2000-03-30 | 2001-10-11 | Q2100, Inc. | Apparatus and method for heating a polymerizable composition |
| US6632535B1 (en) | 2000-06-08 | 2003-10-14 | Q2100, Inc. | Method of forming antireflective coatings |
| US6702564B2 (en) | 2001-02-20 | 2004-03-09 | Q2100, Inc. | System for preparing an eyeglass lens using colored mold holders |
| US6676398B2 (en) | 2001-02-20 | 2004-01-13 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a prescription reader |
| US6808381B2 (en) | 2001-02-20 | 2004-10-26 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a controller |
| US6676399B1 (en) | 2001-02-20 | 2004-01-13 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having sensors for tracking mold assemblies |
| US6752613B2 (en) | 2001-02-20 | 2004-06-22 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a controller for initiation of lens curing |
| US6709257B2 (en) | 2001-02-20 | 2004-03-23 | Q2100, Inc. | Eyeglass lens forming apparatus with sensor |
| US6790022B1 (en) | 2001-02-20 | 2004-09-14 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a movable lamp mount |
| US6655946B2 (en) | 2001-02-20 | 2003-12-02 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a controller for conveyor and curing units |
| US6790024B2 (en) | 2001-02-20 | 2004-09-14 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having multiple conveyor systems |
| US6726463B2 (en) | 2001-02-20 | 2004-04-27 | Q2100, Inc. | Apparatus for preparing an eyeglass lens having a dual computer system controller |
| US6758663B2 (en) | 2001-02-20 | 2004-07-06 | Q2100, Inc. | System for preparing eyeglass lenses with a high volume curing unit |
| US6712331B2 (en) | 2001-02-20 | 2004-03-30 | Q2100, Inc. | Holder for mold assemblies with indicia |
| US6612828B2 (en) | 2001-02-20 | 2003-09-02 | Q2100, Inc. | Fill system with controller for monitoring use |
| KR100763168B1 (en) * | 2001-05-15 | 2007-10-16 | 엘지.필립스 엘시디 주식회사 | Vertical type cleaner |
| US6464484B1 (en) | 2002-03-30 | 2002-10-15 | Q2100, Inc. | Apparatus and system for the production of plastic lenses |
| JP5461771B2 (en) * | 2007-12-07 | 2014-04-02 | 日本写真印刷株式会社 | Molding mold positioning structure |
| CN101637951B (en) * | 2008-07-31 | 2012-10-10 | 鸿富锦精密工业（深圳）有限公司 | Wafer level optical lens forming device and alignment method thereof |
| KR101634353B1 (en) * | 2008-12-04 | 2016-06-28 | 삼성전자주식회사 | Micro lens, method for manufacturing the micro lens, apparatus for manufacturing the micro lens, camera module including the micro lens |
| JP2011189565A (en) * | 2010-03-12 | 2011-09-29 | Fujifilm Corp | Mold for molding and molding method |
| CN101941228B (en) * | 2010-08-26 | 2012-06-06 | 北京科技大学 | Preparation method of electric heating ceramic die for precision spray forming |
| JP6465021B2 (en) * | 2013-06-12 | 2019-02-06 | コニカミノルタ株式会社 | Optical element manufacturing method |
| CN105538607A (en) * | 2016-01-22 | 2016-05-04 | 苏州艾力光电科技有限公司 | Optical device ceramic mold conveniently take out product |
| CN109264972B (en) * | 2018-08-11 | 2021-06-04 | 浙江黄岩环日光学有限公司 | Rear mold of lens mold and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2253697A (en) * | 1938-07-11 | 1941-08-26 | Jenkel Davidson Optical Compan | Die for molding or casting optical lenses |
| US2333051A (en) * | 1941-11-24 | 1943-10-26 | Univis Lens Co | Thickness-shrinkage-controlled die assembly |
| GB650692A (en) * | 1944-11-28 | 1951-02-28 | Teksun Inc | Injection mold for use in molding opthalmic lenses and other articles |
| US2516373A (en) * | 1946-11-09 | 1950-07-25 | Domar Products Inc | Mold for making integral plastic frames and lenses |
| FR1128971A (en) * | 1955-04-13 | 1957-01-14 | Improvements in the manufacture of ophthalmic or optical elements in plastics | |
| IT990526B (en) * | 1972-02-02 | 1975-07-10 | Deutsche Spiegelglas Ag | INJECT FUSION MOLD FOR THE PRODUCTION OF HIGHLY POLYMERIC SHAPED BODIES IN RAMIC GLASS |
| US4876042A (en) * | 1987-12-28 | 1989-10-24 | Canon Kabushiki Kaisha | Molding processing using a reproducible molding die |
| US5176839A (en) * | 1991-03-28 | 1993-01-05 | General Electric Company | Multilayered mold structure for hot surface molding in a short cycle time |
-
1996
- 1996-03-18 DE DE19610563A patent/DE19610563A1/en not_active Withdrawn
-
1997
- 1997-03-05 EP EP97907071A patent/EP0891246B1/en not_active Expired - Lifetime
- 1997-03-05 DE DE59704018T patent/DE59704018D1/en not_active Expired - Lifetime
- 1997-03-05 KR KR1019980707295A patent/KR20000064606A/en not_active Application Discontinuation
- 1997-03-05 WO PCT/EP1997/001105 patent/WO1997034752A1/en not_active Application Discontinuation
- 1997-03-05 CN CN97193183A patent/CN1214005A/en active Pending
- 1997-03-05 CA CA002249279A patent/CA2249279A1/en not_active Abandoned
- 1997-03-05 IL IL12606197A patent/IL126061A0/en unknown
- 1997-03-05 JP JP9533082A patent/JP2000506463A/en active Pending
- 1997-03-05 BR BR9708095A patent/BR9708095A/en not_active Application Discontinuation
- 1997-03-05 AU AU19254/97A patent/AU715356B2/en not_active Ceased
- 1997-03-05 AT AT97907071T patent/ATE202967T1/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| KR20000064606A (en) | 2000-11-06 |
| ATE202967T1 (en) | 2001-07-15 |
| EP0891246B1 (en) | 2001-07-11 |
| BR9708095A (en) | 1999-07-27 |
| DE59704018D1 (en) | 2001-08-16 |
| IL126061A0 (en) | 1999-05-09 |
| JP2000506463A (en) | 2000-05-30 |
| AU715356B2 (en) | 2000-01-20 |
| WO1997034752A1 (en) | 1997-09-25 |
| DE19610563A1 (en) | 1997-09-25 |
| CN1214005A (en) | 1999-04-14 |
| EP0891246A1 (en) | 1999-01-20 |
| AU1925497A (en) | 1997-10-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Discontinued |