US 5,411,564 AGranted

Pneumatic plunger mechanism for a glassware forming machine

AssigneeI.M.T.E.C. Enterprises, Inc.

InventorJames A. Bolin

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Abstract

Both blow-and-blow and press-and-blow plunger mechanisms for use in forming a parison from a gob of fluid glass in a individual section (IS) of a glassware forming machine are fully pneumatically controlled. Plunger and thimble pistons affirmatively position a thimble and a plunger in consistently repeatable positions during loading of the gob, counterblowing or pressing an initial opening in the parison, and transferring the formed parison. No springs or other mechanical components which are prone to cause inconsistencies or failures are employed. The plunger mechanism is preferably suspended from the frame of the IS by a plunger case assembly to avoid the problems associated with a support foot. The plunger case assembly allows the plunger mechanisms to be easily interchanged or replaced, to be adjusted to accommodate different types of operation and sizes and configurations of glass article produced, while still communicating pressurized air to the plunger mechanisms to achieve these effects.

Claims72

Dependent claims

A pneumatically operated plunger mechanism for use in an IS of a glassware forming machine to form a gob of fluid glass into a parison, comprising:

a housing having at least two cylinders, each cylinder containing a piston therein to allow movement of the piston along a length of the cylinder;
a plunger piston positioned in a first one of the cylinders to move in the first cylinder in a plunger stroke;
a plunger connected to the plunger piston to move between a retracted position relative to the housing to and a fully extended position upon movement of the plunger piston in the first cylinder;
a thimble piston positioned in a second one of the cylinders to move in the second cylinder in a thimble stroke;
a thimble connected to the thimble piston to move between a retracted position relative to the housing and a fully extended position upon movement of the thimble piston in the second cylinder;
air passageways in the housing to communicate pressurized air to the cylinders to move each piston in its cylinder along the stroke of each piston;
and
the thimble, the thimble piston, the plunger and the plunger piston interoperatively connected with one another to move the plunger from its retracted position to an intermediate extended position upon movement of the thimble from its retracted position to its fully extended position upon application of pressurized air to the second cylinder and without application of pressurized air to the first cylinder, to move the plunger to its fully extended position upon the application of pressurized air to the first cylinder, and to move the plunger and the thimble to their retracted positions upon application of pressurized air to the first cylinder.

5 more elements

A method of forming a gob of fluid glass into a parison in an IS of a glassware forming machine of a type having a blank mold in which the gob is formed into the parison, comprising the steps of:

providing a pneumatically operated plunger mechanism comprising a housing having at least two cylinders, a plunger piston positioned in a first one of the cylinders to move in a plunger stroke, a thimble piston positioned in a second one of the cylinders to move in a thimble stroke, a plunger connected to the plunger piston to move between a retracted position relative to the housing and a fully extended position with movement of the plunger piston in the first cylinder, a thimble connected to the thimble piston to move between a retracted position relative to the housing and a fully extended position, and air passageways within the housing to communicate pressurized air to the cylinders to move each piston along its stroke;
positioning the plunger mechanism relative to the blank mold to allow movement of the plunger and the thimble with respect to the blank mold;
inserting a gob of glass into the blank mold prior to the formation of the parison;
removing the parison from the blank mold after it is formed;
and
forming the gob into the parison while the glass is in the blank mold by steps comprising:
moving the plunger from its retracted position to an intermediate extended position and moving the thimble from its retracted position to its fully extended position by applying pressurized air to the second cylinder and without applying pressurized air to the first cylinder;
moving the plunger to its fully extended position by applying pressurized air to the first cylinder;
and
moving the plunger and the thimble to their retracted positions by applying pressurized air to the first cylinder.

7 more elements

Dependencies are inferred from the claim text.