Apparatus for producing oriented plastic strap

United States Patent im

Van Erden et al.

■ ■lllil Iff 1 HUB

US005707660A [ii] Patent Number: [45] Date of Patent:

5,707,660 Jan. 13, 1998

[54] APPARATUS FOR PRODUCING ORIENTED PLASTIC STRAP

[75] Inventors: Donald L. Van Erden, Wildwood;

Manuel C. Enriquez, Morton Grove; Hans Weltekamper, Lincolnshire, all of HI.

[73] Assignee: Signode Corporation. Glenview, 111.

[21] Appl. No.: 794,923
[22] Filed: Feb- 4, 1997

Related U.S. Application Data

[60] Continuation of Ser. No. 528,282, Sep. 14,1995, abandoned, which is a division of Ser. No. 353,721, Dec. 12, 1994, Pat No. 5,525,287, which is a continuation-in-part of Ser. No. 958,803, Oct. 9, 1992, Pat. No. 5,387,388.

[51] Int CI.6 B29C 25/08

[52] U.S. CI 425/1744; 264/175; 264/210.5;

425/327; 425/363; 425/461

[58] Field of Search 425/363,327,

425/174.4, 461, 465, DIG. 235; 264/175, 117.19, 210.5, DIG. 45, 289.6

[56] References Cited

U.S. PATENT DOCUMENTS

2,055,205 9/1936 Pereyra 425/363

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3,083,410 4/1963 McGlamery 264/280

3,290,420 12/1966 Orser 264/210

3,351,697 11/1967 Hufcagel et al 264/288.4

3,354,023 11/1967 Dunnington et al 161/165

3,376,601 4/1968 Seanoretal 18/2

3,387,068 6/1968 Scudder 264/210.5

3,394,045 7/1968 Gould 161/164

3,619,460 11/1971 Chill 264/2*8.4

3,651,196 3/1972 Starkweather, Jr. 264/280

3,859,027 1/1975 Messner 425/363

3,871,808 3/1975 Ancker 425/367

3,954,934 5/1976 Newby 264/175

4,038,012 7/1977 Sander 425/363

4,118,454 10/1978 Mikietal 264/288.4

4,234,536 11/1980 Thiel et al 264/522

4,311,658 1/1982 Nicoll 425/363

An apparatus for producing an oriented plastic strap having a predetermined desired thickness for use in connection with the strapping of packages or the like. Heating is provided in connection with the surface of the sheet workpiece which is exposed to the ambient air prior to entry of the workpiece into the nip defined between the pair of rollers such that both surfaces will have similar temperature levels so as to exhibit similar density properties, and still further, the edge portions of the sheet workpiece are also heated so as to advantageously control the degree of flatness of the sheet material or workpiece across the width thereof. The flatness quality of the sheet workpiece can also be achieved through means of specially contoured milling rollers defining the zero gap assembly nip. or by means of specially contoured extrusion dies, whereby the edge portions are rendered thinner as compared to the central portion of the sheet workpiece such that upon milling and stretching of the workpiece, which operations tend to thicken the edge portions of the sheet workpiece, the edge portions will exhibit thickness dimensions commensurate with the thickness dimension of the central portion of the sheet workpiece.

27 Claims, 4 Drawing Sheets