Patent ID: 8142177

Claim:
An installation for blow moulding hollow thermoplastic bodies, comprising at least one mould carrier to which a respective removable mould can be connected via fluid connection means, said installation comprising at least one pressurized temperature-controlled fluid circuit passing through at least said carrier and said respective mould, and automatic means for shutting off said circuit being provided in at least said carrier, wherein said installation comprises: at least one enclosure comprising at least one variable-volume chamber provided with a fluid connection to said pressurized temperature-controlled fluid circuit, and generating means for generating an adjustably pressurized auxiliary fluid able to vary between a maximum pressure substantially equal to a pressure of a pressurized temperature-controlled fluid present in said circuit and a minimum pressure substantially equal to atmospheric pressure, said generating means being connected to said enclosure outside of said variable-volume chamber in such a way that said variable-volume chamber is subjected to an opposing pressure of said adjustable pressure auxiliary fluid, by which generating means, before said mould is disconnected from said mould respective carrier, said opposing pressure of said auxiliary fluid is reduced from said maximum pressure to substantially said minimum pressure, and said pressure of said pressurized temperature-controlled fluid can be reduced in said variable-volume chamber until said pressure is substantially atmospheric pressure, in such a way as to reduce the risk of pressurized temperature-controlled fluid being sprayed out of said carrier if said mould is disconnected from said mould respective carrier when said means for automatically shutting off said circuit are not working.