US 4,173,161 A · Trim press

Abstract

A trim press for severing cup-shaped articles from a sheet of thermoplastic material in which the articles have been integrally formed as by a vacuum forming operation. A horizontally reciprocable punch is driven to sever articles positioned in a stationary die by a linkage arranged to drive the punch at a relatively slow speed during the severing operation to achieve a smooth shearing separation of the relatively soft thermoplastic material. The sheet is fed into the die in step-by-step movement through vertical sheet guides fixedly mounted in a treadle which is reciprocated with the punch at a proportionate speed. A flexible sheet guide connected between the guides in the treadle and a fixed point on the machine frame flexes to accommodate reciprocation of the treadle while continuously guiding the sheet to the guides on the treadle. Feed fingers mounted on the treadle advance the sheet to the die in step-by-step movement synchronized with the stroke of the punch.

Claims13

Dependent claims

In a trim press for severing cup-shaped articles formed in synthetic plastic sheet material from the sheet, said press including a frame, die means on said frame for receiving an article integral with said sheet to locate the article relative to said frame, reciprocable punch means movable on said frame to and from said die means for severing an article located in said die means from said sheet upon the forward stroke of said punch means, drive means for driving said punch means in reciprocation, and feed means for intermittently feeding said sheet with articles formed therein to said die means in synchronism with the stroke of said punch means;

the improvement wherein said feed means comprises a treadle mounted on said frame for reciprocating movement along a first path parallel to the path of movement of said reciprocable punch means, first means coupling said treadle to said punch means for coordinating the movement of said treadle with the stroke of said punch means, sheet guiding means fixedly coupled to said treadle for guiding said sheet in movement to said die means, and feed finger means for feeding said sheet to said die means in intermittent movement coordinated with the stroke of said punch means.

In a trim press for severing cup-shaped articles integrally formed in a sheet of relatively soft synthetic plastic material from the sheet, said press including a frame, die means on said frame having a recess for receiving an article integral with said sheet to locate the article relative to said frame, reciprocable punch means movable on said frame to and from said die means and having cutter means for severing an article located in said die means from said sheet upon movement of said punch means to the forward end of its stroke, drive means for driving said punch means in reciprocation, and feed means for intermittently feeding said sheet with articles formed therein to said die means in synchronism with the stroke of said punch means;

the improvement wherein said drive means comprises flywheel means driven at a constant speed of rotation, link means coupled between said flywheel, said frame and said punch means for driving said punch means in a reciprocatory cycle wherein the speed of said punch means as it approaches the forward end of its stroke is substantially less than the speed of said punch means as it approaches the opposite end of its reciprocatory stroke, and said feed means comprises a treadle mounted on said frame for reciprocatory movement along a path generally parallel to the path of movement of said punch means, and first means coupling said treadle to said punch means for movement therewith at proportionate speeds to insert successive articles into said recess in synchronism with the stroke of said punch means.

In a trim press for severing cup-shaped articles formed in synthetic plastic sheet material from the sheet, said press including a frame, die means on said frame for receiving an article integral with the sheet to locate the article relative to said frame, punch means mounted on said frame for reciprocatory movement along a horizontal path to and from said die means for severing an article located in said die means upon the forward stroke of said punch means, drive means for driving said punch means in reciprocatory movement, and feed means for intermittently feeding a sheet with articles formed therein to said die means in synchronism with the stroke of said punch means;

the improvement wherein said feed means comprises a treadle mounted on said frame for reciprocatory movement on said frame along a path parallel to the reciprocatory path of said punch means at a location above said die means, first guide means fixedly mounted on said treadle for guiding said sheet along a vertical path extending downwardly through said treadle, and flexible second guide means for guiding said sheet from a location on said frame above said treadle along a downwardly curved path merging with said vertical path throughout the full range of movement of said treadle.

Dependencies are inferred from the claim text.

Trim press

Life of this patent

Trim press

Life of this patent

Abstract

Claims13