Mechanism for shearing discrete gobs of molten glass

Abstract: Shears are supported for reciprocating displacement within an open frame so that they can be conjointly displaced from retracted positions to advanced overlapping positions where a runner of molten glass will be severed. A pair of covers close the open frame except for the central portion where the runners pass through. A pip having a plurality of holes is secured to the front edge of the covers so that coolant can be directed downwardly and inwardly against the reciprocating shears.

Description: In conventional glassware forming machines the ware is formed from a gob of molten glass sheared from a molten runner discharged from a feeder. The shears will heat up due to direct contact with the molten gob and from radiant heating. U.S. Patents numbered 4,813,994; 4,859,227 and 4,924,740 disclose conventional shear mechanisms. It is an object of the present invention to provide a very effective structure for cooling the shear blades. The invention generally comprises a shear mechanism for shearing discrete gobs from at least one runner of molten glass comprising a frame, open at the top, having opposed ends joined by a pair of sides, at least one pair of opposed shears supported within the frame for reciprocating displacement from a retracted position proximate the frame ends to an advanced position, characterized by a pair of covers for partially closing the open frame and overlying the retracted shears, the covers including opposed spaced front edges extending transverse to the direction of displacement of the shears from one side of the frame to the other side of the frame, a conduit secured to each of the front edges for directing coolant downwardly in a selected direction against the retracted shears, and including means for setting the direction within a selected range, the setting means being selectively located outside the partially closed frame. Other objects and advantages of the present invention will become apparent from the following portion of this specification and from the accompanying drawings which illustrate a presently preferred embodiment incorporating the principles of the invention. Referring to the drawings: Figure 1 is an oblique view of a shear mechanism made in accordance with the teachings of the present invention; and Figure 2 is an elevational view of one of the cooling tube assemblies shown in Figure 1. The shear mechanism has pairs of opposed shears 10 which are supported within a housing 12 for reciprocating displacement (indicated in Figure 1 by the double ended arrows) between retracted and advanced positions. A pair of shears, when advanced, shear a discrete gob of molten glass from a runner of molten glass 14 supplied from a suitable feeder (not shown) which moves downwardly as indicated by the vertical arrows in Figure 1. The open top of the housing is partially closed by a pair of covers 16, each of which is made up of two panels 18 joined together by a hinge 20. The front edge 22 of each cover 16 extends transverse to the direction of shear movement and overlies the shears at their retracted positions as shown in Figure 1. Secured to the bottom of the cover and defining the front edge 22 is a tube or conduit 30 (Figure 2) having a plurality of radial slots 32 which extend through the lower quadrant facing the associate shears at their retracted position. Within this tube 30 is located a coolant delivery pipe 34 having a set of holes 36 located to correspond with the number and location of the shears. This will minimize pressure losses due to coolant being forced to areas without need. The delivery pipe has a knurled knob 38 for rotating the delivery pipe to aim these holes 36 at the desired angle which can lie within the angular range of the radial slots which extend through the lower quadrant of the tube facing the shears at their retracted position (rearwardly and downwardly as shown by the arrows in Figure 1) and the pipe is held in this axial position with the holes and slots aligned and orientated at the desired angle by a set screw 40 which is received by a threaded hole in the enlarged end 42 of the tube 30. Coolant which can be air or water or a mixture of air and water, for example, is supplied from a suitable source 50.

Claims: A shear mechanism for shearing discrete gobs from at least one runner of molten glass comprising a frame (12), open at the top, having opposed ends joined by a pair of sides, at least one pair of opposed shears (10) supported within said frame for reciprocating displacement from a retracted position proximate said frame ends to an advanced position, characterized by a pair of covers (16) for partially closing said open frame and overlying said retracted shears, said covers including opposed spaced front edges (22) extending transverse to the direction of displacement of said shears from one side of said frame to the other side of said frame, conduit means (30, 34) secured to each of said front edges for directing coolant downwardly in a selected direction against said retracted shears, and including means (40) for setting said direction within a selected range, said setting means being selectively located outside said partially closed frame. A shear mechanism according to claim 1, wherein said conduit means comprises a tube (30) having a plurality of axially spaced slots (32) extending circumferentially through a selected angle, a delivery pipe (34) located within said tube having a plurality of holes (36) axially aligned with at least some of said slots, and means (40) for securing said tube and said delivery pipe together with said holes and slots in axial alignment and with said holes at any selected location within said circumferential slots.

Inventors: WRIGHT DOUGLAS W, WRIGHT, DOUGLAS W.
Applicants: EMHART GLASS MACH INVEST, EMHART GLASS MACHINERY INVESTMENTS INC.
Application year: 1992
Main classification: C03B7
IPC codes: C03B7