BOTTOM OF A HOLLOW BODY OBTAINED BY BLOWING OR STRETCH-BLOWING A PREFORM OF A THERMOPLASTIC MATERIAL, AND HOLLOW BODY COMPRISING SUCH A BOTTOM

• US 20110309090A1
• Filed: 07/13/2007
• Published: 12/22/2011
• Est. Priority Date: 08/08/2006
• Status: Active Grant

• Current Assignee: Sidel Participations (Tetra Laval Holdings BV)
• Original Assignee: Sidel Participations (Tetra Laval Holdings BV)
• Inventors: Derrien, Mikael, Boukobza, Michel
• Granted Patent: US 9,302,805 B2
• Time in Patent Office: Days
• US Class Current: 220/600
• CPC Class Codes: B65D 1/0261 Bottom construction B65D1/06 takes precedence
• CPC Class Codes: B65D 1/0284 having a discontinuous contact surface, e.g. discrete feet

Abstract

Bottom (2) of a hollow body obtained by blowing or stretch-blowing a preform of a thermoplastic material, wherein said bottom (2) includes a transverse support surface (4) and, on either side of said transverse support surface (4), a transverse outer edge (5) and a concave inner wall with a transverse central portion (10) comprising a pellet (11) of a low-crystallinity material, said pellet corresponding to the injection point of the perform; the bottom (2) comprises reinforcing ribs (1) having an outer edge (12) adjacent to the outer edge (5) of the bottom (2) as well as an inner edge (13) adjacent to the transverse central portion (10) but not reaching said transverse central portion (10), wherein said reinforcing ribs (1) flare from their outer edge (12) toward their inner edge (13).

Claims

1. Bottom of hollow body obtained by blowing or stretch-blowing of a preform of thermoplastic material, said bottom comprising a transverse support surface, and on either side of said transverse support surface:

a transverse outer edge;

a concave inner wall with a transverse central part containing a pellet of material of low crystallinity, said pellet corresponding to the injection point of the preform;

said bottom comprising reinforcing ribs having an outer edge in proximity to the outer edge of the bottom, said reinforcing ribs having an inner edge in proximity to the transverse central part but without reaching said transverse central part, wherein the reinforcing ribs flare out from their outer edge toward their inner edge.

2. Bottom of hollow body as claimed in claim 1, wherein the reinforcing ribs have a bottom wall of substantially constant width over the whole length of said ribs.

3. Bottom of hollow body as claimed in claim 1, wherein the outer edge of the reinforcing ribs do not reach the outer edge.

4. Bottom of hollow body as claimed in claim 1, wherein at least one rib has a plane of vertical symmetry.

5. Bottom of hollow body as claimed in claim 4, wherein both lateral flanges of each rib provided with a plane of symmetry are substantially facing each other at the extreme distal part of said ribs, and particularly adjacent to their outer edge.

6. Bottom of hollow body as claimed in claim 1, wherein the pellet of material of low crystallinity projects from the outer face in the transverse central part.

7. Bottom of hollow body as claimed in claim 1, wherein the outer edge is placed at a height h5 with respect to the transverse support surface, the transverse central part being placed at a height h10 with respect to the transverse support surface.

8. Bottom of hollow body as claimed in claim 1, wherein, with the exception of the reinforcing ribs, the bottom is in the form of a body of revolution around an axis substantially perpendicular to its transverse support surface.

9. Bottom of hollow body as claimed in claim 8, wherein, in vertical radial cross-section, between the outer edge and the transverse support surface, the bottom has a profile that is:

adjacent to the outer edge, substantially tangent to a direction perpendicular to the transverse support surface,

adjacent to the transverse support surface, substantially tangent to said transverse support surface.

10. Bottom of hollow body as claimed in claim 9, wherein it has, in vertical radial cross-section between the outer edge and the transverse support surface (4), a substantially parabolic profile.

11. Bottom of hollow body as claimed in claim 9, wherein the bottom has a transverse support surface that is annular in shape.

12. Bottom of hollow body as claimed in claim 11, wherein, starting from said annular transverse support surface and proceeding toward the axis of revolution, the bottom first has an annular step, then a substantially parabolic profile connecting said step to the transverse central part.

13. Hollow body of thermoplastic material, especially a polyester such as PET, obtained by blowing or stretch-blowing of a preform, said hollow body comprising a side wall and a bottom joined to said side wall, wherein said bottom is as presented in claim 1.