Closure apparatus and method of closing an opening

Closure apparatus comprising:

• a collar, having an opening defined therethrough;
• a closure, said closure closing said opening in a closed position and being spaced away from said opening in an open position,
• a closure carriage for mounting said closure and moving said closure between said closed and said open position, said closure carriage comprising first and second closure grip parts, said closure carriage comprising a closure grip part drive for driving said first and said second closure grip parts into or out of engagement with said closure.

A method of closing an opening formed in a collar, comprising:

• moving a closure from an open position to a closed position, said closure closing said opening in said closed position;
• and
• rotating a locking ring from an unlocked position to a locked position, wherein said collar has a collar outer surface and at least one engagement formation formed on said collar outer surface, said closure having a closure outer surface with at least one second engagement formation formed on said closure outer surface, said locking ring having a locking ring inner surface and at least one third engagement formation and at least one fourth engagement formation formed on said locking ring inner surface, said locking ring being configured so that said third engagement formation engages one of said first and second engagement formations in said locked position to hold said closure in said closed position and so that in said unlocked position, said fourth engagement formation is spaced apart from said other of said first and second engagement portions, to permit said closure to be moved into said open position.

A method of closing an opening formed in a collar, comprising moving a closure from an open position to a closed position, said closure closing said opening in said closed position, said closure being mounted on a closure carriage, said closure mounted on said closure carriage being moved between said closed position and said open position, said closure mount comprising first and second closure grip parts, said closure carriage comprising a closure grip part drive for driving said first and second closure grip part into engagement with said closure.

Closure apparatus, comprising:

• collar means having a collar periphery and having a collar inner surface defining an opening,
• closure means, having a closure periphery, said closure means being for closing said opening,
• a bearing structure being located around said collar periphery or said closure periphery, locking ring means being mounted for rotation with respect to said closure means and said opening on said bearing structure, so that said locking ring means is rotatable between a locking position for locking said closure means to said opening and an unlocked position for permitting said closure means to be moved away from said opening.

Closure apparatus comprising:

• collar means, having an opening defined therethrough;
• closure means, said closure means closing said opening in a closed position and being spaced away from said opening in an open position,
• closure carriage means for mounting said closure means and moving said closure means between said closed and said open position, said closure carriage means comprising first and second closure grip parts, said closure carriage comprising closure grip part drive means for driving said first and said second closure grip parts into or out of engagement with said closure means.