Rotary dancer for a packaging machine

Abstract

The present invention relates to a packaging machine ( 1 ), which unrolls a lower film web ( 8 ) from a supply roller ( 52 ) and transports it intermittently or continuously along the packaging machine and thereby forms packaging recesses ( 6 ) in the lower film web ( 8 ) in a forming station ( 2 ), after which the packaging recesses are filled with a product ( 16 ) to be packaged, wherein an upper film web ( 14 ) is subsequently sealed onto the lower film web ( 8 ) in a sealing station ( 15 ), wherein the upper film web ( 14 ) is unrolled from a supply roller ( 22 ). Provided downstream of the supply roller is a dancer ( 20 ), which has at least one, preferably two rollers ( 23.1, 23.2 ), which are provided on a linkage ( 23.4 ), which, driven by a rotary drive, rotates about an axis of rotation ( 23.3 ) and thereby stores a certain length of film web ( 8, 14 ) and/or produces a certain tension in the film web ( 8, 14 ).

1 . A packaging machine comprising:
 a forming station; and   a sealing station;   wherein the packaging machine unrolls a lower sheet-material web from a supply roll of the lower sheet-material web, the packaging machine transports the lower sheet-material web in an intermittent or continuous manner along the packaging machine;   wherein packaging cavities are formed in the lower sheet-material web in the forming station, the packaging cavities are then filled with a product,   wherein after the packaging cavities are filled with the product, an upper sheet-material web is sealed onto the lower sheet-material web in the sealing station;   wherein the upper sheet-material web is unrolled from a supply roll of the upper-sheet material web;   wherein the packaging machine comprises a dancer that is provided downstream of at least one of the supply roll, the dancer having two rollers, which are provided on a linkage which, driven by a rotary drive, rotates the dancer about a rotary pin provided between the two rollers; and   wherein the dancer stores a certain length of the lower sheet-material web and the upper sheet-material web and/or generates a desired level of tensioning in the lower sheet-material web and the upper sheet-material web.   
     
     
         2 . The packaging machine as claimed in  claim 1 , wherein the packaging machine comprises a means that senses an angular position of the linkage. 
     
     
         3 . The packaging machine as claimed in  claim 1 , wherein the rotary drive is a pneumatic drive, a servomotor or a stepping motor, or the rotary drive is a rotary motor with a transmission. 
     
     
         4 . The packaging machine as claimed in  claim 1 , wherein at least one of the two rollers are mounted by means of bearings at two opposite ends. 
     
     
         5 . The packaging machine as claimed in  claim 4 , wherein the bearings are supported on a wall. 
     
     
         6 . The packaging machine as claimed in  claim 1 , wherein the rollers are grounded. 
     
     
         7 . The packaging machine as claimed in  claim 1 , wherein a sheet-material brake provided downstream of the dancer. 
     
     
         8 . The packaging machine as claimed in  claim 7 , wherein the sheet-material brake is mounted by means of bearings in a pivotable manner such that the sheet-material can be pivoted about a vertical pin. 
     
     
         9 . The packaging machine as claimed in  claim 7 , wherein the sheet-material brake has a first part and a second part, which are provided for movement, in particular rotation, in relation to one another by way of a pin. 
     
     
         10 . The packaging machine as claimed in  claim 1 , wherein the packaging machine comprises a cutting and adhesive-bonding table. 
     
     
         11 . The packaging machine as claimed in  claim 10 , wherein the cutting and adhesive-bonding table has apertures connected to a vacuum means. 
     
     
         12 . The packaging machine as claimed in  claim 11 , wherein the apertures can be provided optionally with a suction-attachment means or a dummy plug. 
     
     
         13 . The packaging machine as claimed in  claim 1 , wherein the packaging machine comprises rollers in a case of which a rotary spindle is connected to a rotary body of a roller by means of a laser weld seam. 
     
     
         14 . The packaging machine as claimed in  claim 13 , wherein at least one of the rollers has a rotary bearing, which is grounded. 
     
     
         15 . A method of threading a sheet-material web into a dancer, comprising:
 transferring rollers of the dancer into a threading-in position; and   drawing the sheet-material web along a straight line through the dancer for the threading-in.   
     
     
         16 . The method as claimed in  claim 15 , wherein for threading the sheet-material web into a sheet-material brake, one part of the sheet-material brake is moved away, in particular rotated away, from another part the sheet-material brake. 
     
     
         17 . The packaging machine as claimed in  claim 5 , wherein the wall is located on one side of the lower sheet-material web or the upper sheet-material web. 
     
     
         18 . The packaging machine as claimed in  claim 1 , wherein the dancer is fully enclosed by a housing. 
     
     
         19 . The packaging machine as claimed in  claim 12 , wherein at the adhesive-bonding table, an end of a used-up sheet-material roll is connected to a start of a new sheet-material roll. 
     
     
         20 . A packaging machine comprising:
 a forming station;   a sealing station;   a dancer, the dancer comprising two rollers, the rollers are provided on a linkage which, driven by a rotary drive, rotate the dancer about a rotary pin provided between the two rollers, the dancer is fully enclosed by a housing;   a means that senses an angular position of the linkage;   a sheet-material brake provided downstream of the dancer, the sheet-material brake is mounded by means of bearings in a pivotable manner such that the sheet-material brake is pivotable about a vertical pin; and   a cutting and adhesive-bonding table, the cutting and adhesive table having apertures connected to a vacuum means, at the adhesive-bonding table, an end of a used-up sheet-material roll is connected to a start of a new sheet-material roll;   wherein at least one of the two rollers of the dancer are mounted by means of bearings at two opposite ends, the bearings are supported on a wall, the wall is located on   one side of the lower sheet-material web or the sheet-material web;   wherein the rollers are grounded;   wherein the packaging machine unrolls a lower sheet-material web from a supply roll of the lower sheet-material web, the packaging machine transports the lower sheet-material web in an intermittent or continuous manner along the packaging machine;   wherein packaging cavities are formed in the lower sheet-material web in the forming station, the packaging cavities are then filled with a product;   wherein after the packaging cavities are filled with the product, an upper sheet-material web is sealed onto the lower sheet-material web in the sealing station;   wherein the upper sheet-material web is unrolled from a supply roll of the upper-sheet material web:   wherein dancer that provided downstream of at least one of the supply rolls;   wherein the dancer stores a certain length of the lower sheet-material web and the upper sheet-material web and generates a desired level of tensioning in the lower sheet-material web and the upper sheet-material web.