Abstract: A pattern holder 12 and a sand tank 14 are rotatably mounted on a frame 16 so that the pattern holder can be inverted over and sealably mounted atop the sand tank. A vented pattern 26 is secured to the pattern holder and forms a first chamber between one side of the pattern and the interior of the pattern holder. A second chamber 90 is formed between the other side of the pattern and the interior of the sand tank when the pattern holder adjoins the sand tank. O-ring seals 32 and 80 isolate the chambers from the atmosphere so that a partial vacuum can be formed therein. A mixture 84 of sand and a gas-curable binder is provided in the sand tank so that the mixture will fall onto the pattern upon inverting the sand tank over the pattern holder. A flexible line 42 is provided for controllably introducing a gas catalyst into the chamber 38 in order to cure a portion of the sand-binder mixture to form a shell mold 94 of a predetermined thickness on a pattern face 36 of the pattern.

Abstract: The specification discloses a strike off apparatus for leveling and compacting mounds of sand extending above the upper edges of open-top mold boxes of varying heights carried in succession along a pathway. A pair of pivotally supported rollers extend across the pathway. A sensor determines the height of a sand mound in a mold box before it reaches the rollers. An elevating mechanism responsive to the sensor adjusts the rollers to a height so that they level and compact the sand mound as the mold box is carried thereunder. A control system including electrical and hydraulic circuits is provided for automatically controlling the cyclical operation of the apparatus.

Abstract: The specification discloses a bottom board feeder apparatus for feeding bottom boards onto the top surface of mold boxes of varying heights. The bottom boards are supplied in succession to the apparatus by a first conveying line. The mold boxes are supplied in succession to a board receiving position adjacent the apparatus by a second conveying line. The apparatus includes a proximity sensor for detecting the height of a mold box in the board receiving position and an elevating mechanism responsive to the sensor for raising a bottom board so that the bottom surface of the board is at least as high as the top surface of the box. The apparatus also includes a shuttle mechanism for pushing the board onto the top surface of the box after the board has been raised. A control system including electrical and hydraulic circuits is provided for automatically controlling the cyclical operation of the apparatus.

Abstract: The specification discloses a method and apparatus for combining high speed horizontal and high speed vertical continuous mixing of sand and binder ingredients for mold making purposes. Sand supplied by a hopper assembly and liquid binder ingredients supplied by injection assemblies are fed into the rearward ends of a pair of side-by-side, horizontally extending cylindrical mixing chambers. They are rapidly mixed and conveyed forwardly by blade assemblies which extend centrally through the horizontal mixing chambers and are rotated at from about 300 rpm to about 1500 rpm. The mixtures are then discharged into a vertically extending cylindrical mixing chamber where they are rapidly mixed by a blade assembly which extends centrally through the vertical mixing chamber and is rotated at from about 300 rpm to about 800 rpm. The final mixture is then discharged from the vertical mixing chamber downwardly into a mold box.

Abstract: A mixing apparatus for mixing particulate material is described in which a plurality of different shaped blades are employed for thorough rapid mixing as the material moves downward through a mixing chamber and for impelling the mixed material downward through a discharge opening at the bottom of such chamber. A pair of convoluted lower mixing blades, which spiral downward and inward, are used to mix, to impel the material downward through the discharge opening, and to scrape such material from the conical bottom surface of the mixing chamber. First and second pairs of longitudinal intermediate mixing blades of different lengths positioned above the convoluted blades mix and scrape the material from the cylindrical side surface of the mixing chamber.