| 摘要 |
<p>A foundry molding machine is provided with a pattern plate (86) surrounded by and movable in a well form (87). In a preferred form springs (105, 106) bias the well form upwardly around the pattern plate to form a well. The pattern plate and well form are mounted on a squeeze table (31) and cooperate with the underside of a conventional flask which in turn engages an upset (53) to form a mold chamber for receiving molding sand. In such preferred form the sand is blown under very low pressure into the chamber through a slotted squeeze head (47). As the squeeze table moves upwardly, sand is initially squeezed from the top against the squeeze head while the flask, upset, well form and pattern plate move upwardly as a unit. When a selected level of the flask is reached, preferably when the top is flush with the squeeze head, upward movement of the upset is stopped while the table continues upwardly. The pattern plate then telescopes upwardly within the well form while the flask and well form are held fixed. This compresses the springs supporting the well form. The squeeze continues with the sand being compressed both from the squeeze head and from the pattern plate concurrently until the pattern plate is just even with or slightly below the bottom of the flask. At such time, the table moves down for draw as the springs extend and to permit the mold to clear the machine. Other forms of the present invention provide embodiments utilizing a dumpfill (155) of the flask in combination with an equalizing cylinder squeeze head (156). In yet another embodiment, the well form may be mounted by a piston-cylinder assembly (221-222) for movement independently of the pattern plate thus enabling the depth of the well to be adjusted between cycles.</p> |
