Cmi International, Inc.

Daniel L Merrill

Steve M Sunday

John R Synder

John L Seaver

Chuck O Eckholm, Jr

An abrasive machining assembly (10) wherein a worktable (14) is rotatably supported on a frame (12) for rotation about a table axis (A) and a plurality of platens (32) are supported on the worktable (14) with each of the platens (32) being adapted for supporting a workpiece to be machined by a machining disc (38) rotating about a tool axis (B). Each platen (32) is rotatably supported for rotation about a platen axis (C) which is radially spaced from the table axis (A) a different distance than the tool axis (B) whereby each of the platens (32) rotates about a platen axis (C) which is parallel to and offset from the tool axis (B) when positioned in the workstation. The assembly is characterized by a drive mechanism for selective driving engagement with the workstation platen (32) to rotate the workstation platen (32) and for disengaging the workstation platen (32) during the indexing of the worktable (14) to move the workstation platen (32) out of the workstation while moving another platen (32) into the workstation. This drive mechanism comprises a vertically movable shaft (56) which is rotated by a pulley (70) and selectively moved up and down by a pneumatic actuator (64) to engage and disengage the workstation platen (32).

Abrasive machining assembly

Disc with coolant passages for an abrasive machining assembly

A hold-down mechanism (88) is provided for holding a base plate (32) of a casting assembly (20) in engagement with a crucible (28). The hold-down mechanism (88) includes a plurality of Belleville-type washers (89) for allowing relative movement while maintaining a predetermined force holding the base plate (32) in engagement with the crucible (28). The hold-down mechanism includes a plurality of tension rods (90) and a plurality of forks (91) each having a pair of spaced fingers (92), each of the rods (90) being paired with one of the forks (91). Each of the rods (90) has a threaded end (93) and the Belleville-type washers (89) are disposed about the threaded end (93) of each of the rods (90) with a threaded nut (94) engaging the threads (93) of each of the rods (90) for compressing the washers (89) against the fingers (92) of the forks (91).

Low-pressure casting machine hold-down system

The subject invention is characterized by a mechanism for moving the tilt plate (45) laterally of the guide posts (38) to a loading position outside the operating area within the assembly so that the attachment surface faces sufficiently upwardly to allow a cope (36) and drag (34) defining a mold to rest thereon under the force of gravity. A plurality of crank arms (48) are fixed to and extend upwardly from one lateral edge of the tilt plate (45) to a distal end. A pair of hydraulic cylinders (51) are disposed above the movable platen (43) with a first connection (52) to the distal ends of the crank arms (48) and a second connection (53) to the movable platen (43) for rotating the crank arms (48) to thereby rotate the tilt plate (45) about a tilt axis (50) between an operating position within the assembly and the loading position outside the assembly and facing upwardly. A support ledge, defined by a plurality of removable stakes (46), extends upwardly from the attachment surface in the loading position for receiving and holding a mold against the force of gravity in the loading position while the mold is secured to the tilt plate (45) by cope clamps (47).

Mold loading in low-pressure casting

The invention is characterized by a rack mechanism (60) interconnecting a fixed platen (41) and a movable platen (43) for preventing the movable platen (43) from cocking relative to its guide posts (38) during vertical movement thereof. The rack mechanism (60) includes a gear rack (61) paired with each of the guide posts (38) with the bottom end of each gear rack (61) secured to the movable platen (43), and a spur gear (71) in meshing engagement with each of the gear racks (61) and supported on the fixed platen. A box-like framework interconnects the gear racks (61) and a synchronizing drive system simultaneously rotates the spur gears (71) in unison and includes parallel shafts (72) on opposite sides of the framework with two of the spur gears (71) supported on each of the shafts (72) and in meshing engagement with two of the gear racks (61). The running tolerances between the spur gears (71) and the gear racks (61) can be adjusted by pillow blocks (76) supporting the shafts (72).

Growing community of inventors

Montaque, MI, United States of America

Daniel L Merrill