Packaging method and apparatus
According to one embodiment a packaging method is provided in which a tube is supplied in a forward movement direction. The method includes a folding step in which the tube is acted on in a manner that is transverse to the forward movement direction, folding part of the tube in a folding direction, and a sealing and cutting step after which a tube closed at one end and a package closed and separated from the tube are obtained. During the folding step the tube is held transversely, and a tear is generated in the folding direction between the acted on and held parts of the tube. The tube is sealed on both sides of the tear and cut at the height of the tear. Packaging machines for carrying out the method are also disclosed. Suitable.
1. A packaging machine for making flat bottom packages, the packaging machine comprising:
a driving device for supplying a tube of a film material in a forward movement direction;
an actuation device configured to contact the tube in a manner that is transverse to the forward movement direction to laterally fold a first part of the tube inwardly in a folding direction transverse to the forward movement direction to produce a fold in the tube;
a first holding device configured to hold a second part of the tube in a manner that is transverse to the forward movement direction, the tube including a line of weakness and the actuation device being configured to act on the line of weakness to produce a partial lateral tear in a part of the tube that is located between the actuation device and the first holding device, the partial lateral tear extending transverse to the forward movement direction and in a manner that does not fully separate the tube into two parts; and
a sealing and cutting device configured to produce first and second transverse seals and a transverse cut located between the first and second seals to produce, upstream the transverse cut, a closed end tube that includes the fold, and to produce, downstream the transverse cut a sealed package;
a cutting tool configured to generate the line of weakness in the tube transverse to the forward movement direction; and
a control device that is configured to cause the actuation device to contact the tube in the manner that is transverse to the forward movement direction to produce in the tube the partial lateral tear after the line of weakness is generated, the control device being configured to cause the sealing and cutting device to produce the first and second transverse seals and transverse cut when the line of weakness is located facing the sealing and cutting device.
2. The packaging machine according to claim 1 , further comprising a second holding device configured to hold the first part of the tube in a manner that is transverse to the forward movement direction, the first part being spaced a distance away from the second part in the forward movement direction, wherein the control device is configured to cause the cutting tool to generate the line of weakness while both the first and second holding devices respectively hold the second and first parts of the tube.
3. The packaging machine according to claim 2 , wherein the control device is configured to cause the second holding device to release holding the first part of the tube after the line of weakness is generated, and to subsequently cause the actuation device to act on the first part of the tube to produce the fold.
4. The packaging machine according to claim 1 , wherein the sealing and cutting device comprises the cutting tool that generates the line of weakness when in a first position, the cutting tool further being configured to make the transverse cut in the tube when in a second position, the cutting tool comprising a first cutting profile when in the first position that is configured to generate the line of weakness and a second cutting profile when in the second position that is configured to produce the transverse cut in the tube, the control device being configured to move the cutting tool between the first and second position.