Method for the Ultrasonic Welding of a Strip

Abstract

The invention relates to a method for the ultrasonic welding of a strip consisting of a plastic material for the production of cigarette products, in which method the strip has two free ends which are heated in a connection region by means of ultrasound and joined together to form a closed strip. Ultrasound at a frequency of more than 22 kHz is used.

Claims

1. A method for the ultrasonic welding of a tape composed of a plastics material for the production of cigarette products, wherein the tape has two free ends which in a connection region by ultrasonic means are heated and connected to one another so as to form a closed tape, characterized in that ultrasound at a frequency of more than 22 kHz is used.

2. The method as claimed in claim 1, characterized in that ultrasound at a frequency in a range from 22 to 100 kHz is used.

3. The method as claimed in claim 1, characterized in that ultrasound at a frequency in a range from 25 to 60 kHz is used.

4. The method as claimed in one of claim 1, characterized in that ultrasound at a frequency in a range from 30 to 45 kHz is used.

5. The method as claimed in one of claim 1, characterized in that ultrasound at a frequency in a range from 32 to 38 kHz is used.

6. The method as claimed in one of claim 1, characterized in that ultrasound at a frequency in a range from 34 to 36 kHz is used.

7. A tape for the production of cigarette products, having a woven fabric which has warp threads and weft threads that are composed of a plastics material, said tape in a connection region being connected by ultrasonic welding, characterized in that the woven fabric has warp threads in the entire connection region.

Description

[0020] In the drawing:

[0021] FIG. 1 shows a tape for the production of cigarette products prior to connecting the two free ends of said tape; and

[0022] FIG. 2 shows the tape from FIG. 1 in the ultrasonic welding.

[0023] FIG. 1 shows a tape 1 for the production of cigarette products (not illustrated) such as, for example, cigarettes, filters, or alternative cigarette products such as, for example, so-called e-cigarettes. The tape 1 can be a garniture tape for producing the cigarette product, or a suction tape for transporting tobacco.

[0024] When the tape 1 is configured as a garniture tape, it can be used in a machine in which filters for cigarettes are produced in the form of continuous or at least comparatively long filter strands which are also referred to as filter tows, for example. The garniture tape could also be used as a vacuum tape for transporting various objects or materials such as, for example, tobacco or filter material. In the case of the tape 1 being embodied as a suction tape, said suction tape can be used for transporting tobacco fibers, for example. Since garniture tapes as well as suction tapes are known in principle, the specific use thereof will however not be discussed in more detail here.

[0025] The tape 1 has a woven fabric 2 which in a manner known per se is composed of warp threads 3 and weft threads 4. Since the production of the woven fabric 2 from the warp threads 3 and the weft threads 4 is also known per se, this is likewise not discussed in more detail here. It is only to be mentioned that the weft threads 4 are situated so as to be continuous on both free ends 5 and 6 of the tape 1, that is to say that said weft threads 4 are not removed prior to connecting the two free ends 5 and 6 of the tape 1 as described hereunder.

[0026] The warp threads 3 as well as the weft threads 4 are composed of a plastics material, preferably of a polymer material having a crystalline or semi-crystalline structure. The polymer material is in particular a material from the polyetherketone family. The materials PEK, PEEK, PEKK, PEEKK are particularly preferable. The warp threads 3 and the weft threads 4 are preferably monofilament threads.

[0027] A step of a method for the ultrasonic welding of the two free ends 5 and 6 of the tape 1 so as to form a continuous tape is illustrated in FIG. 2. By means of an ultrasonic generation installation 7, for example a sonotrode, the tape 1 in a connection region 8 in which the two free ends 5 and 6 are placed on top of one another, herein is heated by ultrasonic means, on account of which the two free ends 5 and 6 of the tape 1 are connected to one another such that a continuous tape 1 is created. The woven fabric 2 of the tape 1 produced in this manner has the weft threads 4 in the entire connection region 8.

[0028] Ultrasound at a frequency of more than 22 kHz is used in the heating of the two free ends 5 and 6 of the tape 1. Ultrasound at a frequency from 22 to 100 kHz is more preferably used. Ultrasound at a frequency in a range from 25 to 60 kHz is more preferably used. Ultrasound at a frequency in a range from 30 to 45 kHz is more preferably used. Ultrasound at a frequency in a range from 32 to 38 kHz is more preferably used. Most preferably, ultrasound at a frequency in a range from 34 to 36 kHz is used.

[0029] The ultrasonic generation installation 7, or the sonotrode, respectively, can be part of an entire device by way of which the tape 1 can optionally be produced in a fully automatic manner.