Method and an apparatus for blowing a container in a blowing mould
View Patent ↗The invention concerns a method of manufacturing a container in a blowing mold, the blown container ( 22; 72; 82 ) having a neck and a bottom aligned along a longitudinal axis (A) and being enclosed within a blowing mold ( 12; 70; 80 ), the blowing mold comprising two side halves ( 12 a, 12 b; 70 a, 70 b; 80 a; 80 b ) which are in contact with each other along a joint plane (P) when the blowing mold is in a closed position, the blown container having at least one transverse dimension in a longitudinal cross-section including the longitudinal axis, characterized in that the method comprises a step of moving apart the two side halves ( 12 a, 12 b; 70 a, 70 b; 80 a; 80 b ) of the blowing mold along a substantially transverse direction, the two side halves being moved apart from the joint plane (P) over an overall distance that is less than the greatest transverse dimension of the blown container and that enables extraction of the blown container from the blowing mold ( 12; 70; 80 ).
1. A method of manufacturing a blown container in a blowing mold, the blown container having a neck and a bottom aligned along a longitudinal axis and being enclosed within a blowing mold, the blowing mold comprising a first side half and a second side half, the first side half comprises a first side half mold face and the second side half comprises a second side half mold face, the first side half mold face and the second side half mold face are in contact with each other along a joint plane when the blowing mold is in a closed position, the blown container having at least one transverse dimension in a longitudinal cross-section including the longitudinal axis, the method comprises moving apart the first side half and the second side half along a transverse direction to separate the first side half mold face from the second side half mold face, the first side half and the second side half being moved apart from the joint plane over an overall distance that is less than the greatest transverse dimension of the blown container and that enables extraction of the blown container from the blowing mold.
2. The method of claim 1 , wherein the overall distance is dependent on the shape of the outer surface of the blown container and the at least one transverse dimension thereof.
3. The method of claim 2 , wherein the overall distance is dependent on the transverse dimension of the neck of the blown container.
4. The method of claim 3 , wherein the overall distance is equal to the transverse dimension of the neck when the transverse dimension is less than the transverse dimension of the bottom and the transverse dimension of the container between the neck and the bottom is being kept constant or increasing.
5. The method of claim 1 , wherein the overall distance is equal to half the difference between the greatest and the smallest transverse dimensions of the blown container when the transverse dimension of the bottom is less than the greatest transverse dimension of the blown container.
6. The method of claim 1 , wherein the blown container comprises a waist having a first transverse dimension D1 that is less than a second and a third transverse dimension D2 and D3 respectively of two respective convex portions of the blown container arranged on either part of the waist.
7. The method of claim 6 , wherein the overall distance is equal to half the difference between the transverse dimensions Di and D1, where i equals 1 or 2.
8. The method of claim 7 , wherein the difference between the transverse dimensions is (D2−D1) if
the convex portion with the transverse dimension D2 is arranged above the waist and
either D2 is equal to or greater than D3
or D2 is less than D3 and the transverse dimension of the blown container bottom is equal to D3.
9. The method of claim 1 , comprising extracting the blown container from the open blowing mold.
10. The method of claim 1 , wherein the blown container is extracted from underneath the blowing mold.
11. The method of claim 1 , wherein the blowing mold comprises a bottom part, the method comprises moving the bottom part of the blowing mold on which rests the blown container away from the first side half and the second side half.
12. The method of claim 1 , wherein, prior to moving apart the first side half and the second side half, the method comprises:
stretching a preform placed within the blowing mold; and
injecting a liquid into the preform to cause expansion of the preform within the blowing mold while the preform is being stretched, thereby leading to the blown and liquid-filled container.