Leesona Corporation

Leesona Corporaton

George A West

George L Pickard

Albert W Arends

William F Kent

Wilbur P Winton

Edward J Russell

A thermoforming machine having opposed mold platens includes a linkage system driven in cyclic movement by rotary cam mechanism to cyclically shift the platens between their open and closed position. The cam mechanism is driven by a variable speed motor which is controlled in a manner such that the rotary speed of the cam mechanism during different portions of a cam revolution may be set to a speed which is different than the rotary speed of the cam mechanism during other portions of each revolution. By adjusting the speed differential or by adjusting the angular extent of that portion of a revolution of the cam mechanism over which the different speed is maintained the time duration of any chosen portion of the cycle may be adjusted independently of the time duration of other portions of the cycle.

Differential pressure forming machine with variable mold closed cycle

An oscillating canopy is employed in the feeding of an elongate sheet of synthetic plastic material having articles, such as cups, for example, formed in the sheet, to a die which trims the articles from the sheet. The canopy has a downwardly concave curved upper portion upon which the sheet is supported by a series of rollers. The canopy is driven in forward and return strokes in pivotal movement about an axis located at a radial distance from the curved upper portion which is a greater distance from the discharge end of the curved upper portion than from the sheet receiving end so that tension is maintained on the sheet during the feeding stroke. The sheet-supporting rollers are mounted for rotation in one direction only, this direction being that in which the rollers can roll relative to the sheet on the return stroke of the canopy.

Trim press with oscillating canopy sheet feed

A method and apparatus for lining the interior of a container with plastic sheet material. An open topped container is elevated upon a support through a passage in a lower die member into contact with the under surface of a sheet of heated thermoplastic material overlying the upper end of the passage. A plug assist member is then employed to deform the sheet into conformation with the interior of the container. Upon withdrawal of the plug assist member, an upper die member is lowered into shearing relationship with the lower die member to shear the sheet around the upper periphery of the container. The support, with the lined container in place, is then further elevated to raise the lined container upwardly through the opening thus sheared in the sheet and through a passage extending vertically through the upper die member. The plastic lined container is discharged from the apparatus by pushing it transversely across the flat upper surface of the upper die member.

Container lining

A method for lining the interior of a container with plastic sheet material. An open topped container is elevated upon a support through a passage in a lower die member into contact with the under surface of a sheet of heated thermoplastic material overlying the upper end of the passage. A plug assist member is then employed to deform the sheet into conformation with the interior of the container. Upon withdrawal of the plug assist member, an upper die member is lowered into shearing relationship with the lower die member to shear the sheet around the upper periphery of the container. The support, with the lined container in place, is then further elevated to raise the lined container upwardly through the opening thus sheared in the sheet and through a passage extending vertically through the upper die member. The plastic lined container is discharged from the apparatus by pushing it transversely across the flat upper surface of the upper die member.

Container lining method

An indexing system for synthetic plastics molding machinery, wherein plastic web gripping drive elements are employed to feed a plastic web in planar indexing movements to the molds of the machine, utilizes a conventional pump driven hydraulic motor connected with the web gripping drive elements by drive transmission mechanism incorporating a brake for positively halting the web gripping elements in predetermined position. A stroke measuring control device driven by the drive transmission mechanism in a path of movement corresponding with the indexing moving of the web gripping elements first decelerates the movement of the web gripping elements and then positively halts them in a predetermined position. Alternatively, a photoelectric eye sensitive to the position of the web can stop the web.

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Clare, MI, United States of America

George A West