Device for extruding a polymer frame onto a plate-shaped object

Abstract

This invention concerns a device used in the process of manufacturing an automobile pane 1 equipped with a polymer frame 52 placed on the edge of the pane 1. The frame 52 is extruded onto the pane 1 which can be moved by means of a suitable support in such a way that the edge of the pane travels through a recess in an extrusion head 25 and 40. The recess of the extrusion head 40 preferably includes a U-shaped jaw 41 straddling the edge of the pane. At the front extremity of the two half-jaws of the U-shaped jaw 41 there are disposed sealing ledges or shoes 42 and 43 which are movable perpendicularly to the surfaces of the pane and which, during extrusion, bear upon the surfaces of the pane. Alternatively, the extrusion head can include a fixed jaw where the sealing ledges or shoes slideably and sealingly contact the plate.

What is claimed is:  
     
       1. An apparatus for producing a shaped polymer frame on a plate having top and bottom main surfaces and a peripheral edge, which comprises: 
       an extrusion die having a body which defines a plate-receiving recess for receiving the edge of the plate and portions of the main surfaces adjacent thereto;  
       a first sealing ledge which is movable between (1) a retracted position which allows entry of the plate edge into the recess, and (2) an engaged position in contact with one of the main surfaces of the plate which defines an open area between the die body, sealing ledge and the plate in the shape of a polymer frame; and  
       means for moving the plate relative to the extrusion die, where the moving means advances the edge of the plate through the recess to receive the shaped polymer frame on the edge and one of the main surfaces of the plate.  
     
     
       2. The apparatus of claim  1  which further comprises means for moving the first sealing ledge between the retracted and engaged positions in a direction which is essentially perpendicular to the main surfaces of the plate. 
     
     
       3. The apparatus of claim  2  wherein the moving means comprises spring means for biasing the first sealing ledge toward the engaged position and rod means for returning the first sealing ledge to the retracted position. 
     
     
       4. The apparatus of claim  1  wherein the recess includes a first surface which is spaced from the plate and a second surface which contacts the plate on the surface opposite that which is contacted by the first sealing ledge in the engaged position, so that the polymer frame is provided on the edge and a portion of one main surface of the plate. 
     
     
       5. The apparatus of claim  4  wherein the portions of the first sealing ledge and recess which contact the plate include a layer of an elastic material thereon to facilitate sliding movement upon the plate. 
     
     
       6. The apparatus of claim  1  which further comprises a second sealing ledge which is movable between (1) a retracted position which allows entry of the plate edge into the recess, and (2) an engaged position in contact with the other main surface of the plate. 
     
     
       7. The apparatus of claim  6  wherein one or both of the sealing ledges includes an arcuate surface which assists in the formation of an arcuate portion for the polymer frame. 
     
     
       8. The apparatus of claim  6  wherein the recess includes first and second surfaces which are spaced from the plate, so that the polymer frame is provided on the edge and a portion of each main surface of the plate. 
     
     
       9. The apparatus of claim  1  which further comprises a support wheel which travels along the surface of the plate and compensates for shape tolerances of the plate. 
     
     
       10. An apparatus for producing a shaped polymer frame on a plate having top and bottom main surfaces and a peripheral edge, which comprises: 
       an extrusion die having a one-piece body which defines a plate receiving recess for receiving the edge of the plate and portions of the main surfaces adjacent thereto;  
       said plate receiving recess comprising first and second sealing ledges which are movable between (1) a retracted position which allows entry of the plate edge into the recess, and (2) an engaged position in contact with the main surfaces of the plate which defines an open area between the die body, sealing ledges and the plate in the shape of a polymer frame, wherein the sealing ledges, in the engaged position, provide a seal for said recess and facilitate sliding movement between said die body and said main surfaces; and  
       means for providing relative movement between the die and plate such that the edge of the plate advances through the recess to receive the shaped polymer frame on the edge and at least one of the main surfaces of the plate.  
     
     
       11. The apparatus of claim  10  wherein the portions of the sealing ledges that contact the plate include a layer of an elastic material thereon to facilitate said sliding movement. 
     
     
       12. The apparatus of claim  11  which further comprises selecting the elastic material from the group consisting of thermoplastic foam, elastomeric foam, and thermoplastic coated elastomeric foam. 
     
     
       13. The apparatus of claim  12  which further comprises means for releasably securing the layer of elastic material to the sealing ledge to facilitate replacement of said layer. 
     
     
       14. The apparatus of claim  13  wherein the releasable securing means comprises a backing member for the elastic material, with the backing member including a rib member for engaging a corresponding slot in the sealing ledge. 
     
     
       15. The apparatus of claim  14  wherein the backing member is made of an engineering thermoplastic having sufficient rigidity to retain the rib member in the slot. 
     
     
       16. The apparatus of claim  15  wherein the elastic member is secured to the backing member by an adhesive. 
     
     
       17. The apparatus of claim  10  wherein the recess includes a first surface which is spaced from the plate and a second surface which contacts the plate on the surface opposite that which is contacted by the first sealing ledge, so that the polymer frame is provided on the edge and a portion of one main surface of the plate. 
     
     
       18. The apparatus of claim  10  wherein the recess includes first and second surfaces which are spaced from the plate, so that the polymer frame is provided on the edge and a portion of each main surface of the plate. 
     
     
       19. The apparatus of claim  10  wherein one or both of the sealing ledges includes an arcuate surface which assists in the formation of an arcuate portion for the polymer frame. 
     
     
       20. The apparatus of claim  10  wherein the extrusion die includes two channels for supplying polymer to the open area and means for independently regulating the flow of polymer in each channel. 
     
     
       21. The apparatus of claim  10  which further comprises means for extruding the polymer through the open area and onto the plate. 
     
     
       22. A process for producing a shaped polymer frame on a plate having top and bottom main surfaces and a peripheral edge, which process comprises: 
       placing an extrusion die adjacent the plate edge, wherein the extrusion die has a body which defines a plate-receiving recess for receiving the edge of the plate and portions of the main surfaces adjacent thereto; and a first sealing ledge which is movable between (1) a retracted position which allows entry of the plate edge into the recess, and (2) an engaged position in contact with one of the main surfaces of the plate which defines an open area between the die body, sealing ledge and the plate in the shape of a polymer frame;  
       receiving the plate edge in the recess of the extrusion die;  
       moving the first sealing ledge into contact relation with at least one of the main surfaces of the plate;  
       advancing the plate edge through the recess; and  
       depositing polymer onto the plate edge and a portion of at least one of the adjacent main surfaces through the open area of the die during movement of the plate edge through the recess to provide the polymer frame thereon.  
     
     
       23. The method of claim  22  wherein the polymer is a moisture-hardening reaction polymer which is deposited upon the peripheral edge of the plate as it advances through the recess. 
     
     
       24. The method of claim  22  wherein the first sealing edge moves in a direction which is essentially perpendicular to the main surfaces of the plate and is biased towards the engaged position and the method further comprises returning the first sealing ledge to the retracted position after deposition of the polymer frame. 
     
     
       25. The method of claim  22  wherein the extrusion die further comprises a second sealing ledge which is movable between (1) a retracted position which allows entry of the plate edge into the recess, and (2) an engaged position in contact with the other main surface of the plate, and the method further comprises moving the second sealing ledge into contact relation with the other main surface of the plate before the plate edge is advanced through the recess. 
     
     
       26. The method of claim  25  wherein each sealing ledge is biased towards the engaged position and the method further comprises returning each sealing ledge to the retracted position after deposition of the polymer frame. 
     
     
       27. The method of claim  22  wherein the extrusion die includes two channels for supplying polymer to the open area and the method further comprises independently regulating the flow of polymer in each channel to facilitate the filling of the open area of the extrusion die. 
     
     
       28. The method of claim  22  wherein the recess includes a first surface which is spaced from the plate and a second surface which contacts the plate on the surface opposite that which is contacted by the first sealing ledge in the engaged position, and the method further comprises providing the first sealing ledge and the second surface of the recess with a layer of an elastic material thereon to facilitate sliding movement of the plate through the recess. 
     
     
       29. The method of claim  25  wherein the recess includes first and second surfaces which are spaced from the plate so that the polymer frame is provided on the edge and a portion of each main surface of the plate, and the method further comprises providing each sealing ledge with a layer of an elastic material thereon to facilitate sliding movement of the plate through the recess. 
     
     
       30. The method of claim  25  which further comprises forming an arcuate portion on the polymer frame by providing one or both of the sealing ledges with an arcuate surface which assists in the formation of the polymer frame. 
     
     
       31. The method of claim  22  which further comprises compensating for shape tolerances of the plate as the die travels along the plate. 
     
     
       32. The method of claim  23  wherein the moisture hardening reaction polymer comprises a thermoplastic polyolefin elastomer constituted by isotactic polypropylene and ethylene propylene diene rubber. 
     
     
       33. The method of claim  28  which further comprises selecting the elastic material from the group consisting of thermoplastic foam, elastomeric foam, and thermoplastic coated elastomeric foam. 
     
     
       34. The method of claim  29  which further comprises selecting each elastic material from the group consisting of thermoplastic foam, elastomeric foam, and thermoplastic coated elastomeric foam.