Quad wheel buffering tube clencher capstan

A cable element manufacturing machine comprising:

• one or more payoff reels for supplying one or more optical fibers;
• an extruder for receiving the one or more optical fibers and for extruding a buffer tube around the one or more optical fibers to form a cable element;
• a main capstan for pulling the cable element forward at an advancement speed;
• a cooling section, downstream of said extruder, for cooling and contracting the buffer tube;
• a collection reel, downstream of said cooling section, to take up the finished cable element;
• and
• a buffer tube clencher, between said extruder and at least a portion of said cooling section, for elongating the buffer tube, said buffer tube clencher being characterized by:
• a first set of guiding wheels including:
• a first guiding wheel which rotates about a first axis, said first guiding wheel including a first circular surface to engage an outer surface of the buffer tube;
• and
• a second guiding wheel which rotates about a second axis, said second guiding wheel including a second circular surface to engage the outer surface of the buffer tube, wherein the second axis is spaced from and parallel to the first axis;
• a first gap formed between said first and second circular surfaces;
• a first biasing element applying a first biasing force causing said first circular surface to move toward said second circular surface, wherein said first circular surface can move in a direction away from said second circular surface against the first biasing force of said first biasing element when a force is applied to said first circular surface, so that said first gap may become larger, wherein at least one of said first and second guiding wheels is driven to rotate;
• a second set of guiding wheels including:
• a third guiding wheel which rotates about a third axis, said third guiding wheel including a third circular surface to engage the outer surface of the buffer tube;
• and
• a fourth guiding wheel which rotates about a fourth axis, said fourth guiding wheel including a fourth circular surface to engage the outer surface of the buffer tube, wherein the fourth axis is spaced from and parallel to the third axis;
• a second gap formed between said third and fourth circular surfaces;
• and
• a second biasing element applying a second biasing force causing said third circular surface to move toward said fourth circular surface, wherein said third circular surface can move in a direction away from said fourth circular surface against the second biasing force of said second biasing element when a force is applied to said third circular surface, so that said second gap may become larger, wherein at least one of said third and fourth guiding wheels is driven to rotate.

A method of forming a cable element comprising:

• supplying one or more optical fibers from one or more payoff reels to an extruder;
• extruding a buffer tube around the one or more optical fibers to form a cable element;
• advancing the cable element at an advancement speed using a main capstan;
• cooling the cable element in a cooling section;
• elongating the buffer tube after the extruding of the buffer tube and before finishing of the cooling of the buffer tube;
• and
• collecting the cooled cable element on a collection reel, characterized by the elongating of the buffer tube including:
• guiding the buffer tube through a first gap between first and second guiding wheels, while allowing the first guiding wheel to move away from the second guiding wheel against a first biasing force;
• driving a rotation of at least one of said first and second guiding wheels;
• guiding the buffer tube through a second gap between third and fourth guiding wheels, while allowing the third guiding wheel to move away from the fourth guiding wheel against a second biasing force;
• and
• driving a rotation of at least one of said third and fourth guiding wheels.