Method for forming ceramic shell molds

Claim 1

In the production of investment casting molds by building up refractory layers around pattern set-ups, a method of applying refractory material to a plurality of pattern set-ups in a single operation comprising the steps of mounting an array of several pattern set-ups for rotation as a group about an axis transverse to the vertical, the pattern set-ups being spaced radially from said axis and arranged about it with their ends lying in planes transverse to said axis so that when the array is rotated each pattern set-up is moved about said axis between a lowered position and a raised position, rotating the array and moving each set-up to change the angular positions of its outer peripheral proportions, and applying fluent refractory material to the set-ups in the array, whereby the material is caused to uniformly cover the outer peripheral portions of the set-ups as their angular positions are changed.

Claim 10

A method of making refractory molds by building up refractory layers around pattern set-ups, said method being characterized by the procedure of handling several pattern set-ups as a group during formation of the refractory layers around the set-ups in the group and including the steps of: a. grouping a plurality of pattern set-ups in an array so that the set-ups are circumferentially spaced from each other about an axis and so that the ends of the set-ups lie in planes transverse to said axis, b. processing the array of several pattern set-ups through a coating operation in which refractory slurry is applied to each set-up in a single operation, c. processing said array of several pattern set-ups through a stuccoing operation in which refractory particles are applied to the coated set-ups of the array in a single operation, d. hardening the stuccoed coatings around the set-ups, e. repeating the coating and stuccoing operations to build up refractory layers around each set-up in the array, and f. removing the set-ups from the array after refractory layers of the desired thickness have been formed, g. at least one of said operations being carried out by the steps of: i. mounting the array of set-ups for rotation about said axis with said axis being transverse to the vertical height of a tank containing fluent refractory material and so that when the array is rotated each pattern set-up is moved about said axis between the lowered position in which it is at least partially immersed in the refractory material and a raised position in which the set-up is above the refractory material, ii. rotating the array of pattern set-ups through the refractory material while moving each set-up to change the angular positions of its outer peripheral portions so that they are uniformly covered by the refractory material.

Claim 11

A method of making refractory molds by building up refractory layers around pattern set-ups, said method being characterized by the procedure of handling several pattern set-ups as a group during formation of the refractory layers around the set-ups in the group and including the steps of: a. grouping a plurality of pattern set-ups in an array so that the set-ups are circumferentially spaced from each other about an axis and so that the ends of the set-ups lie in planes transverse to said axis, b. processing the array of several pattern set-ups through a coating operation in which refractory slurry is applied to each set-up in a single operation, c. processing said array of several pattern set-ups through a stuccoing operation in which refractory particles are applied to the coated set-ups of the array in a single operation, d. hardening the stuccoed coatings around the set-ups, e. repeating the coating and stuccoing operations to build up refractory layers around each set-up in the array, and f. removing the set-ups from the array after refractory layers of the desired thickness have been formed, g. at least one of said operations being carried out by the steps of: i. mounting the array of set-ups for rotation about said axis with said axis being transverse to the vertical height of a tank containing fluent refractory material and so that when the array is rotated each pattern set-up is moved about said axis between the lowered position in which it is at least partially immersed in the refractory material and a raised position in which the set-up is above the refractory material, ii. rotating the array of pattern set-ups through the refractory material while moving each set-up to change the angular positions of its outer peripheral portions so that they are uniformly covered by the refractory material.