Patent ID: 8714966

Claim:
Apparatus ( 1 ) for the injection moulding of containers in plastic material, comprising: at least a mould ( 2 ) having at least a female matrix die ( 3 ) and at least a corresponding male element ( 4 ) that can be coupled to one another to define a forming inter-space ( 5 ) of at least a container, and at least one centring stem ( 10 ) for centring said male element ( 4 ) with respect to said female matrix die ( 3 ), wherein: said at least one centering stem comprises a first extremity ( 12 ) having at least a locator surface ( 12 a ) for said male element ( 4 ) and a side surface ( 12 b ), said surfaces sliding in a direction (D) transversal with respect to said male element ( 4 ) inside a corresponding centring hole ( 11 ) obtained in said female matrix die ( 3 ), and said surfaces moving with a reciprocating motion between a backward configuration, in which said locator surface ( 12 a ) is arranged in correspondence to the inner surface of said female matrix die ( 3 ), and a forward configuration, in which said locator surface ( 12 a ) abuts said male, element ( 4 ), wherein: said first extremity ( 12 ) of the centring stem ( 10 ) has a cross section decreasing towards said locator surface ( 12 a ) which decreases continuously towards said locator surface ( 12 a ), and said side surface ( 12 b ) is sloped by an angle between 0.05° and 2° with respect to said sliding direction (D).