Method for producing and filling bottom-fold bags and apparatus for execution of the method

Claim 1

A method for producing bottom-fold bags from endless tubular material comprising: inwardly folding the tubular material along a first pair of oppositely spaced fold lines at a juncture of the tubular material and the ends of a flat bottom of the bag being formed to form two lateral, substantially triangularly shaped, inwardly-facing bottom flaps, in the vicinity of which the tubular material is in three layers; simultaneously, inwardly folding the tubular material along a second pair of oppositely spaced fold lines at a juncture of the tubular material and the sides of a flat bottom of the bag being formed, perpendicular to the first pair of fold lines, to form two substantially trapezoidal shaped, inwardly-facing longitudinal bottom flaps; pressing the tubular material forming the two substantially triangular shaped inwardly-facing bottom flaps together and connecting at least two of the three layers; pressing the two trapezoidal shaped longitudinal bottom flaps together and connecting them such that they form a bottom longitudinal seam therebetween, parallel to the second pair of fold lines and perpendicular to the first pair of fold lines, and such that they partially overlap and abut the two triangularly shaped lateral bottom flaps to thereby form a rectangularly shaped flat bottom surface to the tubular material capable of supporting the bag thus formed from the tubular material in a standing position when filled: providing at least one connecting seam substantially at right angles to the bottom longitudinal seam, arranged near each lateral edge of the bag; and providing at least one connecting seam substantially at right angles to the bottom longitudinal seam, arranged near each apex of a triangle formed by the abutment of the inwardly folded triangular shaped lateral bottom flaps and the inwardly folded trapezoidal shaped longitudinal bottom flaps; such that at least one of the connecting seams is linear and is divided in its longitudinal extension.

Claim 2

A method for producing bottom-fold bags from endless tubular material comprising: inwardly folding the tubular material along a first pair of oppositely spaced fold lines at a juncture of the tubular material and the ends of a flat bottom of the bag being formed to form two lateral, substantially triangularly shaped, inwardly-facing bottom flaps, in the vicinity of which the tubular material is in three layers; simultaneously, inwardly folding the tubular material along a second pair of oppositely spaced fold lines at a juncture of the tubular material and the sides of a flat bottom of the bag being formed, perpendicular to the first pair of fold lines, to form two substantially trapezoidal shaped, inwardly-facing longitudinal bottom flaps; pressing the tubular material forming the two substantially triangular shaped inwardly-facing bottom flaps together and connecting at least two of the three layers; pressing the two trapezoidal shaped longitudinal bottom flaps together and connecting them such that they form a bottom longitudinal seam therebetween, parallel to the second pair of fold lines and perpendicular to the first pair of fold lines, and such that they partially overlap and abut the two triangularly shaped lateral bottom flaps to thereby form a rectangularly shaped flat bottom surface to the tubular material capable of supporting the bag thus formed from the tubular material in a standing position when filled: providing at least one connecting seam substantially at right angles to the bottom longitudinal seam, arranged near each lateral edge of the bag; and providing at least one connecting seam substantially at right angles to the bottom longitudinal seam, arranged near each apex of a triangle formed by the abutment of the inwardly folded triangular shaped lateral bottom flaps and the inwardly folded trapezoidal shaped longitudinal bottom flaps; such that at least one of the connecting seams is linear and is divided in its longitudinal extension.

Claim 11

An apparatus for producing and filling bottom-fold bags made of endless tubular material comprising: expansion means for maintaining an expanded shaft of the tubular material and over which the expanded shaft of tubular material is passed; guide means for guiding the expanded shaft of tubular material and which provides a substantially leak-proof central filling zone for the bag being formed; folding means for producing an inward fold in the expanded shaft of the tubular material as it passes over the expansion means to form a flat rectangularly-shaped bottom surface on the bag being formed, the bottom surface having lateral triangularly shaped bottom flaps, and longitudinal trapezoidal shaped bottom flaps, with the tubular material in the vicinity of the triangularly shaped flaps being triple-folded; first sealing means for pressing together the folded-over layers of the tubular material in the vicinity of the triangularly shaped flaps; second sealing means which cooperate with the expansion means and the folding means to seal the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps and form a longitudinal seam between the longitudinal flaps; third sealing means for forming at least one connecting seam at the bottom of the bag being formed near each lateral edge of the bag and for forming at least one connecting seam near the apex of a triangle formed by the abutment of the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps, such that at least one of the connecting seams is linear and is divided in its longitudinal extension.

Claim 12

An apparatus for producing and filling bottom-fold bags made of endless tubular material comprising: expansion means for maintaining an expanded shaft of the tubular material and over which the expanded shaft of tubular material is passed; guide means for guiding the expanded shaft of tubular material and which provides a substantially leak-proof central filling zone for the bag being formed; folding means for producing an inward fold in the expanded shaft of the tubular material as it passes over the expansion means to form a flat rectangularly-shaped bottom surface on the bag being formed, the bottom surface having lateral triangularly shaped bottom flaps, and longitudinal trapezoidal shaped bottom flaps, with the tubular material in the vicinity of the triangularly shaped flaps being triple-folded; first sealing means for pressing together the folded-over layers of the tubular material in the vicinity of the triangularly shaped flaps; second sealing means which cooperate with the expansion means and the folding means to seal the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps and form a longitudinal seam between the longitudinal flaps; third sealing means for forming at least one connecting seam at the bottom of the bag being formed near each lateral edge of the bag and for forming at least one connecting seam near the apex of a triangle formed by the abutment of the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps, such that at least one of the connecting seams is linear and is divided in its longitudinal extension.

Claim 25

An apparatus for producing and filling bottom-folding bags made of endless tubular material, which comprises: a format shaft having a substantially rectangular external periphery over which the tubular material is downwardly passed; a guide shaft at each side of the format shaft, formed by a partition at each side parallel to the format shaft, which is substantially leakproof in relation to a central filling area of the format shaft; a sealing plunger in each guide shaft for pressing together layers of the tubular material which have been folded over onto one another; a horizontally positioned folding tool at each side of the format shaft oriented perpendicularly to and situated just below the format shaft which is capable of moving from a first, outer position of rest to a second inner, actuated position wherein the folding tool is horizontally projected in the tubular material from each side to cause the tubular material to be inwardly folded thereby producing a triple layer of the tubular material in the vicinity of the fold; a transverse sealing tool located below the format shaft which cooperates with the format shaft and the folding tools to form the lateral and longitudinal bottom flaps and the longitudinal bottom seam of the bottom-fold bag being formed; and means for forming at least one connecting seam at the bottom of the bag being formed near each lateral edge of the bag and for forming at least one connecting seam near the apex of a triangle formed by the abutment of the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps, such that at least one of the connecting seams is linear and is divided in its longitudinal extension.

Claim 26

An apparatus for producing and filling bottom-folding bags made of endless tubular material, which comprises: a format shaft having a substantially rectangular external periphery over which the tubular material is downwardly passed; a guide shaft at each side of the format shaft, formed by a partition at each side parallel to the format shaft, which is substantially leakproof in relation to a central filling area of the format shaft; a sealing plunger in each guide shaft for pressing together layers of the tubular material which have been folded over onto one another; a horizontally positioned folding tool at each side of the format shaft oriented perpendicularly to and situated just below the format shaft which is capable of moving from a first, outer position of rest to a second inner, actuated position wherein the folding tool is horizontally projected in the tubular material from each side to cause the tubular material to be inwardly folded thereby producing a triple layer of the tubular material in the vicinity of the fold; a transverse sealing tool located below the format shaft which cooperates with the format shaft and the folding tools to form the lateral and longitudinal bottom flaps and the longitudinal bottom seam of the bottom-fold bag being formed; and means for forming at least one connecting seam at the bottom of the bag being formed near each lateral edge of the bag and for forming at least one connecting seam near the apex of a triangle formed by the abutment of the lateral triangularly shaped bottom flaps and the longitudinal trapezoidal shaped bottom flaps, such that at least one of the connecting seams is linear and is divided in its longitudinal extension.