Apparatus for opening tubes of flexible material

Claim 2

In combination with apparatus for forming a closed bottom of a bag from an essentially flat tube of flexible material including a machine frame, means in said frame for folding the end of said tube to provide a plurality of overlying layers thereof while said end is in motion, means in said frame for moving said end of said tube into said folding means in a predetermined direction for said folding, and means operatively coupled with said folding means for securing said overlying layers to form said bag bottom, apparatus operatively coupled with said folding means for opening said end of said tube while said end is in motion in said direction prior to completion of said folding thereof, comprising: a. a first suction cup; b. a support member; c. means for rotating said suction cup at a predetermined angular velocity about a first axis which is positioned in said support member, said means including a single pivotal connection means on said suction cup for rotatable connection thereof with said support member and for defining said first axis; d. means for rotating said support member at an angular velocity substantially equal to but opposite in direction to said angular velocity provided by said means (c) about a second axis, said second axis being positioned to provide a first essentially tangential passage of the suction face of cup with a first wall of said tube end in substantially the same direction as said predetermined direction of movement of said tube end; and e. means for applying a suction pressure to said suction cup at least in part during said tangential passage of said suction cup face with said first wall.

Claim 3

The appartus of claim 1 further comprising: f. a second suction cup; g. a second support member; h. means for rotating said second suction cup at a predetermined angular velocity about a third axis, said third axis being positioned in said second support member, said means (h) including a single pivotal connection means on said second suctiOn cup for rotatable connection thereof to said second support member and for defining said third axis; i. means for rotating said second support member in synchronism with said means (d) at an angular velocity substantially equal to but opposite in direction to said angular velocity provided by said means (h), about a fourth axis, said fourth axis being positioned in said frame essentially parallel to said third axis and positioned to provide an essentially tangential passage of the suction face of said second cup with a second wall of said tube end in the vicinity of, substantially in the same direction and concurrent with said first tangential passage of said first cup; and j. means for applying a suction pressure to said second suction cup at least in part during said second tangential passage of said second cup face with said second wall.

Claim 4

In combination with apparatus for forming a closed bottom of a bag from an essentially flat tube of flexible material including a machine frame, means in said frame for folding the end of said tube to provide a plurality of overlying layers thereof while said tube end is in motion, means in said frame for moving said tube end into said folding means with a predetermined velocity for said folding, and means operatively coupled with said folding means for securing said overlying layers to form said bag bottom, apparatus operatively coupled with said folding means for opening said tube end while it is in motion at said velocity prior to completion of said folding thereof, comprising: a. a first support member; b. a second support member; c. first and second opposing suction cups, one on each side of the path of movement of said end of said tube in said frame, said first suction cup having a single pivotal connection means thereon defining a first axis of rotation for rotatable mounting of said first suction cup to said first support member; d. means for rotating said first suction cup about said first axis in a first angular direction at a first angular speed; e. mounting means for rotatably mounting said first support member to said frame for rotation thereof about a second axis essentially parallel to said first axis, wherein said mounting means is positioned in said frame to provide a first tangential passage of the face of said first suction cup with a first wall of said tube end in a direction substantially aligned with the direction of movement of said tube end; f. means for rotating said first support member about said second axis at an angular speed essentially equal to said first angular speed and in an angular direction essentially opposite to said first angular direction; g. a single pivotal connection means on said second suction cup for rotatable connection thereof to said second support member, said single pivotal connection means defining a third axis of rotation; h. means for rotating said second suction cup about said third axis at an angular speed substantially equal to said first angular speed and in an angular direction essentially opposite to said first angular diection; i. mounting means for rotatably mounting said second support member to said frame for rotation thereof about a fourth axis essentially parallel to said third axis wherein said mounting means (i) is positioned in said frame to provide an essentially tangential passage of the face of said second cup with the wall of said tube end opposite said first wall but in the vicinity of said first tangential passage and in a direction substantially aligned with the direction of movement of said tube end; and j. means for rotating, in synchronism with the rotation of said first support member, said second support member about said fourth axis at an angular speed essentially equal to said first angular speed and in an angular direction essentially the same as said first angular direction.

Claim 5

In combination with apparatus for forming a closed bottom of a bag from an essentially flat tube of flexible material including a machine frame, means in said frame for folding the end of said tube to provide a plurality of overlying layers thereof while said tube end is in motion, means in said frame for moving said tube end into said folding means with a predetermined velocity for said folding, and means operatively coupled with said folding means for securing said overlying layers to form said bag bottom, apparatus operatively coupled with said folding means for opening said tube end while it is in motion at said velocity prior to completion of said folding thereof, comprising: a. a first support member; b. a second support member; c. first and second opposing suction cups, one on each side of the path of movement of said end of said tube in said frame, said first suction cup having a single pivotal connection means thereon defining a first axis of rotation for rotatable mounting of said first suction cup to said first support member; d. means for rotating said first suction cup about said first axis in a first angular direction at a first angular speed; e. mounting means for rotatably mounting said first support member to said frame for rotation thereof about a second axis essentially parallel to said first axis, wherein said mounting means is positioned in said frame to provide a first tangential passage of the face of said first suction cup with a first wall of said tube end in a direction substantially aligned with the direction of movement of said tube end; f. means for rotating said first support member about said second axis at an angular speed essentially equal to said first angular speed and in an angular direction essentially opposite to said first angular direction; g. a single pivotal connection means on said second suction cup for rotatable connection thereof to said second support member, said single pivotal connection means defining a third axis of rotation; h. means for rotating said second suction cup about said third axis at an angular speed substantially equal to said first angular speed and in an angular direction essentially opposite to said first angular diection; i. mounting means for rotatably mounting said second support member to said frame for rotation thereof about a fourth axis essentially parallel to said third axis wherein said mounting means (i) is positioned in said frame to provide an essentially tangential passage of the face of said second cup with the wall of said tube end opposite said first wall but in the vicinity of said first tangential passage and in a direction substantially aligned with the direction of movement of said tube end; and j. means for rotating, in synchronism with the rotation of said first support member, said second support member about said fourth axis at an angular speed essentially equal to said first angular speed and in an angular direction essentially the same as said first angular direction.

Claim 6

In combination with apparatus for forming a closed bottom of a bag from an essentially flat tube of flexiblE material including a machine frame, means in said frame for folding the end of said tube to provide a plurality of overlying layers thereof while said end is in motion, means in said frame for moving said end of said tube into said folding means in a predetermined direction for said folding, and means operatively coupled with said folding means for securing said overlying layers to form said bag bottom, apparatus operatively coupled with said folding means for opening said end of said tube while said end is in motion in said direction prior to completion of said folding therof, comprising: a. a suction cup; b. a support member; c. a toothed driven member fixed to said suction cup and rotatably mounted to said support member for defining a first axis of rotation of said suction cup with respect to said support member; d. means for rotating said support member about a second axis, said second axis being positioned in said machine frame substantially parallel to said first axis and positioned in said machine frame to provide a first essentially tangential passage of the suction face of said cup with a first wall of said tube end in substantially the same direction as said predetermined direction of movement of said tube end; e. a toothed driving member fixed to said machine frame in a position circumscribing said second axis; f. engagement means for engaging said driven member (c) with said driving member (e) to rotate said suction cup about said first axis in a direction opposite to the direction of rotation of said support member; and g. means for applying a suction pressure to said suction cup at least in part during said tangential passage of said suction cup face with said first wall.

Claim 7

In combination with apparatus for forming a closed bottom of a bag from an essentially flat tube of flexiblE material including a machine frame, means in said frame for folding the end of said tube to provide a plurality of overlying layers thereof while said end is in motion, means in said frame for moving said end of said tube into said folding means in a predetermined direction for said folding, and means operatively coupled with said folding means for securing said overlying layers to form said bag bottom, apparatus operatively coupled with said folding means for opening said end of said tube while said end is in motion in said direction prior to completion of said folding therof, comprising: a. a suction cup; b. a support member; c. a toothed driven member fixed to said suction cup and rotatably mounted to said support member for defining a first axis of rotation of said suction cup with respect to said support member; d. means for rotating said support member about a second axis, said second axis being positioned in said machine frame substantially parallel to said first axis and positioned in said machine frame to provide a first essentially tangential passage of the suction face of said cup with a first wall of said tube end in substantially the same direction as said predetermined direction of movement of said tube end; e. a toothed driving member fixed to said machine frame in a position circumscribing said second axis; f. engagement means for engaging said driven member (c) with said driving member (e) to rotate said suction cup about said first axis in a direction opposite to the direction of rotation of said support member; and g. means for applying a suction pressure to said suction cup at least in part during said tangential passage of said suction cup face with said first wall.

Claim 8

The apparatus of claim 4 further comprising: h. a second suction cup; i. a second support member; j. a second toothed driven member fixed to said second suction cup and rotatably mounted to said second support member for defining a third axis of rotation; k. means for rotating said second support member about a fourth axis, said fourth axis being positioned in said machine frame essentially parallel to said third axis and positioned in said machine frame to provide an essentially tangential passage of the suction face of said second cup with a second wall of said tube end in the vicinity of, substantially in the same direction and concurrent with said first tangential passage of said first cup; l. a second toothed driving member fixed to said machine frame in a position circumscribing said fourth axis; m. engagement means for engaging said driven member (j) with said driving member (l) to rotate said second suction cup about said third axis in a direction opposite to the direction of rotation of said second support member; and n. means for applying a suction pressure to said second suction cup at least in part during said second tangential passage of said second cup face with said second wall.