Splicing device to join together two web materials, unwinding device comprising said splicing device

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• and including means acting selectively on one or another of the moving unit to block one of the two heads, which is to remain deactivated.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• wherein the moving unit of each said head is provided with a movement of oscillation about a first axis of oscillation controlled by said first common control member;
• wherein each said moving unit is disposed essentially symmetrically with respect to a plane, each unit extending from an axis of oscillation which is positioned in proximity to the plane of symmetry, the counter-pressure member and the cutting member being positioned at a greater distance from the plane of symmetry with respect to the axis of oscillation;
• wherein said first axis of oscillation is common to each said moving unit;
• and wherein the plane of symmetry contains said common axis of oscillation.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• and further comprising a brake associated with said moving unit to hold the first web material during the cutting, a second common control member which controls the brake of one or another of said two heads alternately, and an arrangement of stops adapted to act selectively on one or another of said brake to block one said brake to deactivate a respective one of said heads.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• and further comprising a brake associated with said moving unit to hold the first web material during the cutting, wherein each brake is supported oscillating about an axis of oscillation on a respective one of said moving unit, said brake comprising an oscillating arm hinged to said moving unit about an axis of oscillation essentially parallel to the axis of oscillation of the respective moving unit, and axes of oscillation of each said arm of each said brake associated with the two heads are disposed at a side of the common axis of oscillation of the moving unit, each said arm extending on opposite sides with respect to the common axis of oscillation.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• wherein each said moving unit is carried by a carriage movable along a track to adopt at least two operating positions;
• and, wherein said track has a stop member cooperating with stops integral with each said moving unit and having interruptions at least at a level of the operating positions of said moving carriage, to allow selective movement of one or another of each said moving unit by means of said first common control member.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• and wherein a temporary clamping member of an initial edge of the web material to be clamped between the clamping bar and the roller is associated with each said clamping bar and with a respective one of the roller.

A splicing device to join together a first web material and a second web material, comprising two heads, each head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, on which said counter-pressure member and said cutting member are carried;
• wherein a first common control member adapted to cause, through movement imparted to the moving unit of one or another of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• and wherein said first common control member comprises a pair of piston-cylinder actuators in parallel.

A splicing device to join together a first web material coming from a reel being fed, and a second web material, coming from a reel standing by, comprising two heads, each said head comprising:

• a roller associated with a clamping bar to hold an initial edge of the second web material;
• a counter-pressure member cooperating with said roller to press said first web material and said second web material against each other;
• a cutting member;
• a moving unit, oscillating about an axis, on which said counter-pressure member and said cutting member are carried;
• wherein a first common actuator member is mechanically connected to the moving unit and is adapted to impart movement to the moving unit of one or other of said two heads alternately, pinching of the first web material and said second web material between the roller and the counter-pressure member, cutting of the first web material, and release of the second web material;
• wherein each said moving unit of the two heads are disposed essentially symmetrically with respect to a plane of symmetry.