| 摘要 |
#CMT# #/CMT# In a molding assembly for lost-wax casting, with a hollow cylindrical sleeve (2) to be combined with a base (3) (covering the lower opening of the sleeve) having a supporting lug or projection for a model of wax (or the like), the support is in the form of a piece (4) separate from the base main body (3'), to be positioned at different sites in the surface (6') of the base central part (6) and to form the mold cavity base, while being held in place magnetically. #CMT# : #/CMT# An independent claim is included for a supporting piece for a mold or a model of wax (or the like) for use in the molding assembly as above, comprising an at least partially truncated conical body (8) of non-magnetic material, having a housing (8') in its base for mounting of a magnetic insert (7). #CMT#USE : #/CMT# Especially in the production of ceramic dental prostheses. #CMT#ADVANTAGE : #/CMT# Prostheses of different sizes and shapes can be produced without the need to use a large number of bases of different sizes and conicities. The need to use an enlarged mold to receive the an asymmetric model (with consequent waste or material) is also eliminated. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The figure shows a partial side elevation, partially sectioned view of a molding unit. 1 : Molding unit 2 : Hollow cylindrical sleeve 2' : Lower opening in sleeve 3 : Base 3' : Main body of base 4 : Supporting piece 5 : Model 6 : Central part of main body 6' : Surface of central part 7 : Magnetic insert 8 : Non-magnetic body of support 8' : Housing 9 : Circumferential groove or recess #CMT#CERAMICS AND GLASS : #/CMT# Preferred Apparatus: The supporting piece (4) has a magnetic insert (7) and the body (3') of the base (3) is of (or has a surface or core of) ferromagnetic material. The body (8) of the supporting piece is of non-magnetic material (preferably metal, e.g. aluminum), and has a housing in its lower surface for receiving the magnetic insert. Alternatively the body (3') of the base (3) (or its surface or core) is magnetized and the supporting piece is at least partially of ferromagnetic material. The supporting piece is at least partially truncated conical in shape and the base is in the form of a plate with one or more circumferential grooves or recesses (9) to receive the edge of the hollow cylindrical sleeve (2) by bayonet fitting or clamping. The base body has a bean- or kidney-shaped exterior contour with a flattened concave side, and the sleeve has a similar cross-section. The surface of at least the central part (6) of the base body is treated (e.g. chromed or anodized) and the interior surface of the sleeve is optionally chromed or anodized. |
