Method and instrument for unlocking a device having two axially latched bodies

An instrument for unlocking a device having a first body and a second body provided with means of mutual locking by axial latching, said mutual locking means including:

• on said first body, a plurality of axially oriented projecting latching tabs;
• on said second body, a transversely oriented wall provided for each one of said latching tabs with an aperture through which each one of said latching tabs can pass, said transversely oriented wall joining a cylindrical wall faced by said latching tabs when said first body and second body are locked on each other;
• and
• means for preventing the withdrawal of each latching tab which has passed through said aperture;
• the instrument characterised in that it has:
• a sheath having, for each one of said tabs, a portion adapted to be housed between a tab and said cylindrical wall, and adapted, when it enters between the tab and said cylinder wall, to cooperate with said tab to cause it to tilt until said means for preventing withdrawal are released;
• and
• a guidance means, adapted to receive said second body and adapted to move with respect to said sheath in an axial direction, in order to guide, with respect to said sheath, the second body, and therefore the cylindrical wall, in the axial direction.

A method for unlocking a device having a first body and a second body provided with means of mutual locking by axial latching, said mutual locking means having:

• on said first body, a plurality of axially oriented projecting latching tabs;
• on said second body, a transversely oriented wall provided, for each one of said latching tabs, with an aperture through which a latching tab can pass, said transversely oriented wall joining a cylindrical wall faced by said latching tabs when said first body and second body are locked on each other;
• and
• means for preventing the withdrawal of each latching tab which has passed through said aperture;
• the method characterised in that it includes:
• a) the step of positioning said device on a sheath having, for each one of said tabs, a portion adapted to be housed between a tab and said cylindrical wall,
• b) the step of making each portion of said sheath enter between a tab and cylindrical wall so that each said portion cooperates with said tab in order to cause it to tilt until said means for preventing withdrawal are released;
• and
• c) the step of separating said first body and second body from each other;
• wherein said sheath forms part of an unlocking instrument also having a guidance means adapted to move with respect to said sheath in an axial direction, in that said step a) includes a step of positioning said second body on said guidance means and in that said step b) includes a movement of said guidance means with respect to said sheath in order to guide, with respect to said sheath, the second body, and therefore the cylindrical wall, in the axial direction.