Device and method for manufacturing receptacles provided with decorative wrap-around labels by thermoforming
The device includes a mold block having at least one thermoforming chamber ( 28 ) having an inside surface ( 29 ), an axial opening ( 28 A) through which a decorative wrap-around label ( 38 ) can be inserted into the chamber, and a moving end-wall ( 40 ) opposite from the opening. The end-wall is suitable for moving in an end segment ( 28 A) of the chamber ( 28 ) between a positioning high level and at least one thermoforming low level, and the device has at least one tongue-and-groove set comprising a fin ( 42 ) on the end-wall ( 40 ) that is engaged in a notch ( 44 ) in the inside surface of the end segment ( 28 B).
1. A device for manufacturing receptacles provided with decorative wrap-around labels by thermoforming, the device including a mold block having at least one thermoforming chamber that has a side wall defining an inside surface, an axial opening, and a moving end-wall, opposite from the opening, and a wrap-around label insertion block having at least one wrap-around label insertion chamber and a piston mounted to move in the wrap-around label insertion chamber to push a decorative wrap-around label into the thermoforming chamber through said axial opening, the moving end-wall being configured to move along the inside surface in an end segment of the chamber between a positioning high level in which said moving end wall is configured to define an abutment for a lower edge of a wrap-around label placed in the thermoforming chamber and at least one thermoforming low level, and the device comprising at least one tongue-and-groove set comprising a fin on the end-wall, said fin being engaged in a notch in the inside surface of the end segment.
2. A device according to claim 1 , wherein the notch ends at the high level.
3. A device according to claim 1 , wherein the inside surface of the end segment of the chamber has diametrical dimensions that are larger at the high level than at the low level, and the depth of the notch, as measured transversely, is smaller at the high level than at the low level.
4. A device according to claim 1 , wherein the fin projects transversely from an outline of the end-wall having diametrical dimensions that are analogous to the diametrical dimensions of the inside surface of the low level of the end segment in which the notch is formed.
5. A device according to claim 1 , comprising a plurality of tongue-and-groove sets distributed circumferentially.
6. A device according to claim 1 , wherein the tongue-and-groove set comprises a multiplicity of fins distributed uniformly over the circumference of the end-wall and engaged in a multiplicity of notches distributed uniformly over the inside surface of the end segment.
7. A device according to claim 1 , wherein the end-wall is suitable for taking up a plurality of thermoforming low levels, for thermoforming receptacles that are of different depths.
8. A device according to claim 1 , wherein the thickness of a fin lies in the range 0.3 mm to 1 mm, and the width ( 13 ) of a notch ( 44 ) receiving said fin is equal to the thickness of the fin, plus clearance of approximately in the range 0.1 mm to 0.3 mm.
9. A device according to claim 1 , wherein the thickness of a fin is substantially equal to 0.5 mm, and the width of a notch receiving said fin is equal to the thickness of the fin, plus clearance substantially equal to 0.2 mm.
10. A device according to claim 1 , wherein the inside surface of the chamber includes a suction portion situated between the high level and the axial opening.