Process for making containers

• US 4,327,052 A
• Filed: 09/23/1980
• Issued: 04/27/1982
• Est. Priority Date: 09/22/1975
• Status: Expired due to Term

• Current Assignee: Pechiney Plastic Packaging Incorporated (Rio Tinto Limited)
• Original Assignee: National Can Corporation (Triangle Industries, Inc.)
• Inventors: Sauer, Donald G.
• Primary Examiner(s): Silbaugh, Jan H.
• Application Number:
  US06/189,751
• Time in Patent Office: 581 Days
• Field of Search: 264/132, 264/134, 264/294, 264/296, 264/322, 264/259, 264/544, 264/553, 264/523, 264/532, 264/533, 264/512, 264/516, 264/549-551, 425/112, 425/388, 425/523, 425/342.1, 425/343, 425/387.1
• US Class Current: 264/512
• CPC Class Codes: B29C 49/12 Stretching rods
• CPC Class Codes: B29C 51/02 Combined thermoforming and manufacture of the preform
• CPC Class Codes: B29C 51/04 Combined thermoforming and prestretching, e.g. biaxial stretching
• CPC Class Codes: B29C 51/10 Forming by pressure difference, e.g. vacuum
• CPC Class Codes: B29C 51/14 using multilayered preforms or sheets

Abstract

A process for thermoforming laminated hollow articles including a plurality of processing steps wherein a thermoplastic material heated to a plastic state is selectively deposited area-wise on a sheet of thermoplastic material and such resulting laminate of thermoplastic materials is positioned proximate to a female mold of a thermoforming apparatus including preferably a plug assist for a subsequent forming of laminated hollow articles.

Claims

1. A process for plastic container manufacture comprising the steps of:

(A) clamping an outer portion of a preformed thermoplastic member positioned adjacent a female forming means,

(B) relatively projecting a first male forming means into a face of said thermoplastic member to stretch and form said thermoplastic member into a hollow article having an opening and integral side wall and end wall portions.

(C) removing said hollow article from said female forming means and said first male forming means,

(D) relatively positioning said hollow article in operative relationship to a second male forming means,

(E) positioning a container neck forming means around at least a portion of said side wall,

(F) clamping said side wall between said neck forming means and said second male forming means,

(G) projecting said second male forming means within said hollow article to stretch and form said hollow article into an elongated hollow body having an opening an integral side wall and end wall portions,

(H) relatively positioning a blow mold cavity means about said side wall and end wall portions of said elongated hollow body,

(I) positioning sealing means adjacent said opening of said elongated hollow body to seal said opening,

(J) pressurizing the interior of said resulting hollow body by injecting fluid thereinto to enlarge the volume of said hollow body to an extent sufficient to generally conform said wall portions against said blow mold cavity means thereby forming said hollow body into a container,

(K) separating said blow blow molding cavity from said container,

(L) trimming residual portions of said preformed member from said container adjacent said opening, and

(M) removing said formed container.

2. The process as claimed in claim 1 wherein step (I) is further characterized by said sealing means comprising a sleeve slidably mounted over a portion of said second male forming means, said positioning of said sealing means comprising slidably positioning said sleeve within said elongated hollow body with said sleeve clamping said elongated hollow body between said neck forming means and said sleeve.

3. The process of claim 2 wherein step (G) is further characterized by said sealing means cooperating with said neck forming means to form a neck region in said elongated hollow body adjacent said opening.

4. The process of claim 1 wherein step (L) is further characterized by said trimming step comprising first removing said second male forming means from said container and then passing a trimming means through said container adjacent said opening.

5. The process of claim 1 wherein step (K) is further characterized by said second male forming means being positioned against the interior surface of said end wall of said container to support said container when said blow cavity means is removed.

6. The process of claim 1 wherein step (G) is further characterized by said second male forming means cooperating with said neck forming means to form a neck region in said elongated hollow body adjacent said opening.

7. The process of claim 1 wherein step (G) is further characterized by said sealing means cooperating with said neck forming means to form a neck region in said elongated hollow body adjacent said opening.

8. A process for plastic container manufacture comprising the steps of:

(A) supporting a preformed thermoplastic member in a forming position adjacent the mouth of a female forming means, and clamping outer portions of said thermoplastic member,

(B) relatively movably projecting a first male forming body into a face of said thermoplastic member to stretch and form said thermoplastic member into a hollow article having a mouth and intergral side and end wall portions,

(C) separating said female forming means and said first male forming body and relatively positioning said mouth of said article over a second male forming body,

(D) positioning a container neck forming means around said side wall portions,

(E) clamping said side wall portions between said container neck forming means and said second male forming body,

(F) projecting said second male forming body against inner surface regions of said end wall portions to stretch and form said hollow article into an elongated hollow body having said mouth and integral side and end wall portions,

(G) relatively positioning a blow mold cavity means about said wall portions adjacent said container neck forming means,

(H) movably projecting a third male forming body which surrounds a portion of said second male forming body into the inside of said hollow body through said mouth to form a neck region in said hollow body in cooperation with said container neck forming means and to sealingly close said mouth,

(I) pressurizing the interior of said resulting hollow body by injecting fluid thereinto to enlarge the volume of said hollow body to an extent sufficient to generally conform said wall portions against said blow mold cavity means thereby forming said hollow body into a container,

(J) separating said blow mold cavity means from said container while maintaining said container neck forming means and said third male forming body in supporting engagement with said neck region,

(K) separating said second and said third male forming bodies from said container

(L) trimming residual portions of said preformed member from said container about said mouth, and

(M) separating said container neck forming means from said container.

9. The process of claim 8 wherein said container neck forming means is provided with thread forming spirally extending cavity means whereby thread rings are formed in said neck region.

10. The process of claim 8 wherein said preformed member is multilayered.

11. The process of claim 8, wherein in step (J), said second male forming body is further projected into said container to an extent sufficient to support an inner surface region of said end wall while so maintaining.