Clamping apparatus for molding machine

Claim 1

An apparatus for use in molding or casting and adapted to support and clamp together the mold members of a mold comprising: 1. a frame, 2. a pair of platens adapted to support said mold members including, a. a fixed platen affixed at one end of said frame, and b. a movable platen slidably mounted on a medial portion of said frame, 3. a back plate adjustably affixed to said frame at the other end thereof, 4. means for providing rapid reciprocal movement of said movable platen between an advanced position of mold closure and a retracted position of mold opening comprising a fast-acting cylinder having a piston mounted therein for reciprocal movement of relatively small bore and of relatively long stroke mounted on said back plate and having a piston rod the remote end of which is affixed to said movable platen, 5. means for providing a high tonnage clamping force comprising a tonnage cylinder mounted on said back plate coaxially positioned with respect to said fast-acting cylinder and having a piston reciprocably mounted therein, said cylinder having a bore of large cross-sectional area and a stroke of relatively short travel; and 6. means for transmitting tonnage clamping force from said tonnage cylinder to said movable platen comprising a plurality of stress rods each affixed at one end to said movable platen and extending in parallel relationship in the direction of said back plate, said back plate and said tonnage cylinder and piston being provided with apertures having seals therein permitting said stress rods to pass therethrough, and a lock plate rotatably mounted on said back plate and means for rotating said lock plate alternatively to one of two indexing positions, said lock plate having a plurality of apertures so arranged that when said lock plate is in the open index position the ends of said stress rods may pass therethrough, and when said lock plate is rotated to the closed index position, the ends of said stress rods engage said lock plate and force transmitted from said tonnage piston to said lock plate is in turn transmitted to said stress rods.

Claim 2

An apparatus for use in molding or casting and adapted to support and clamp together the mold members of a mold comprising: 1. a frame, 2. a pair of platens adapted to support said mold members including, a. a fixed platen affixed at one end of said frame, and b. a movable platen slidably mounted on a medial portion of said frame, 3. a back plate adjustably affixed to said frame at the other end thereof, 4. means for providing rapid reciprocal movement of said movable platen between an advanced position of mold closure and a retracted position of mold opening comprising a fast-acting cylinder having a piston mounted therein for reciprocal movement of relatively small bore and of relatively long stroke mounted on said back plate and having a piston rod the remote end of which is affixed to said movable platen, 5. means for providing a high tonnage clamping force comprising a tonnage cylinder mounted on said back plate coaxially positioned with respect to said fast-acting cylinder and having a piston reciprocably mounted therein, said cylinder having a bore of large cross-sectional area and a stroke of relatively short travel; and 6. means for transmitting tonnage clamping force from said tonnage cylinder to said movable platen comprising a plurality of stress rods each affixed at one end to said movable platen and extending in parallel relationship in the direction of said back plate, said back plate and said tonnage cylinder and piston being provided with apertures having seals therein permitting said stress rods to pass therethrough, and a lock plate rotatably mounted on said back plate and means for rotating said lock plate alternatively to one of two indexing positions, said lock plate having a plurality of apertures so arranged that when said lock plate is in the open index position the ends of said stress rods may pass therethrough, and when said lock plate is rotated to the closed index position, the ends of said stress rods engage said lock plate and force transmitted from said tonnage piston to said lock plate is in turn transmitted to said stress rods.