Installation for depositing, by means of a microwave plasma, an internal barrier coating in thermoplastic containers

Installation for depositing, by means of a microwave plasma, a barrier coating on the internal surface of containers each comprising a neck and a body and made of a thermoplastic comprising PET, the installation comprising:

• a multiplicity of container treatment stations each comprising a treatment enclosure;
• bottoms which each supports a corresponding container and which move axially to insert and extract the container, placed neck up, into and from the treatment enclosure, via a base of the treatment disclosure;
• and
• an upper block forming a cover which comprises an upper surface and a lower surface disposed on a top of the treatment enclosure proximate the necks of the containers so that the microwave plasma is injected via the cover toward the necks of the containers, the upper block including:
• a vacuum pumping chamber in which connection means for sealed connection to the neck of the container comprises a sleeve of tubular general shape coaxial with the neck of the container, each cover supporting an injector coaxial with said sleeve for injecting a reactive fluid into the container during the treatment,
• wherein members, chosen from among the sleeves and the injectors of several adjacent stations forming a group of stations are fastened to a single support plate that extends as a bridge over upper surfaces of the covers of said adjacent stations,
• said plate and the members of said adjacent stations of the group of stations constitute a unitary assembly that is maneuvered as one piece to fit said members onto the covers of respective adjacent stations or to remove the members therefrom.