| 摘要 |
<p>PURPOSE:To form dental prosthesis having no casting flaw, by constituting the melting guide provided on a rotary plate at a part near to the center thereof of a molten metal accelerating guide and a molten metal outflow guide. CONSTITUTION:The cast 5 held by a heat insulating material 3 is arranged on a rotary plate 1 in a freely detachable manner. The opening part 5a of the cast 5 is turned toward the middle point O and a molten metal guide 2 having an outflow port 2d formed thereto so as to be opposed to the opening part 5a is provided on the middle point O. The guide 2 is formed into a container shape opened at the upper part thereof and consisting of a bottom surface 2c and a wall surface 2a, and the bottom surface 2c is formed horizontally. The wall surfaces 2a is constituted of a radiation part 2a1, a projection part 2a2 and a curved part 2a3, and the projection part 2a2 and the curved part 2a3 are formed into a vortex shape whose radius becomes gradually larger from the middle point O in a clockwise direction and the terminal of the curved part 2a3 reaches an outflow port 2d.</p> |
