[54] THERMOFORMING EQUIPMENT FOR
DIFFERENTIAL PRESSURE FORMING
PRODUCTS IN THERMOPLASTIC
MATERIAL
[75] Inventors: Robert C. Whiteside, Harrison;
Albert W. Arends, Gladwin, both of
Mich.
[73] Assignee: John Brown Inc., Beaverton, Mich.
[21] Appl. No.: 613,864
[22] Filed: May 23,1984
[51] Int. Q." B29C 51/36; B29C 51/44
[52] U.S. a 425/590; 264/153;
264/334; 264/551; 425/292; 425/388; 425/405 R; 425/422; 425/451.6; 425/451.7; 425/592;
425/593
[58] Field of Search 425/145, 161, 162, 292,
425/324.1, 327, 347, 388, 395, 397, 405 R, 422, 451, 451.2, 451.5, 451.6, 589, 590, 592, 593, 451.3; 264/153, 334, 549-551, 553
[56] References Cited
U.S. PATENT DOCUMENTS
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3,166,790 1/1965 Keyes 425/302.1
3,173,174 3/1965 Edwards 425/292
3,216,491 11/1965 Brown et al 165/161
3,338,997 8/1967 Tigner 264/549
3,346,923 10/1967 Brown et al 425/162
3,507,007 4/1970 Martin 425/388
3,561,057 2/1971 Butzko 425/214
3,577,596 5/1971 Bullard et al 425/151
3,585,689 6/1971 Brown et al 425/157
3,719,445 3/1973 Sindelar 425/150
3,726,458 4/1973 Rabl 226/146
3,830,611 8/1974 Irwin 425/415
3,876,488 4/1975 Uemura et al 156/405
3,890,308 6/1975 Collins 425/242
4,158,539 6/1979 Arends et al 425/451.4
4,308,005 12/1981 Zundel 425/388
4,354,816 10/1982 Schepp 425/388
4,368,024 1/1983 Asano 425/388
4,377,377 3/1983 Arends et al 425/451.2
4,428,723 1/1984 Thiel et al 425/324.1
Primary Examiner—Jay H. Woo
Assistant Examiner—Timothy W. Heitbrink
Attorney, Agent, or Firm—Learman & McCulloch
[57] ABSTRACT
Improvements in differential pressure, thermoforming machinery for molding articles in thermoplastic material wherein a mold station incorporates female mold mechanism and opposed mold mechanism, a web advancing mechanism indexes a plastic web in which products are to be formed between said mold mechanisms, a drive moves the female and opposed mold mechanisms between open and closed positions on opposite sides of the plastic web, severing knife means is cooperable with a final increment of said relative movement to dispose said mechanism in closed position to sever the products formed from the web, and ejector mechanism is operable after severing is accomplished and there has been relative movement of said mold mechanisms toward open position to eject the product.
13 Claims, 12 Drawing Figures
