Plastic closure device for tubular bags

Abstract

A plastic closure device ( 1 ) with a lower part ( 2 ) is disclosed which can be fastened in a non-releasable and integrally bonded manner by means of ultrasonic welding to a plastic film or a plastic patch. A flange ( 20 ) of the lower part ( 2 ) is connected by an underside thereof to the plastic layer in an integrally bonded manner by means of introducing ultrasonic energy of a sonotrode into the flange ( 20 ). An energy-introducing arrangement, comprising a plurality of energy-introducing ribs ( 23 ), is used to introduce the ultrasonic energy into the flange ( 20 ), as a result of which the weld parts are welded under the action of a static joining force. Owing to the design according to the invention of the energy-introducing arrangement, a desired connection can be achieved in spite of a reduced static joining force, a reduced ultrasonic energy and, in general, with the use of a reduced welding power by comparison with prior art methods.

1 . A plastic closure device for tubular bags, having a bottom part ( 2 ), comprising a discharge outlet ( 22 ) and a flange ( 20 ) having a flange bottom side ( 200 ) on which there is disposed an energy-introducing arrangement which can be connected to a plastic layer by ultrasonic welding,
 characterized in that   the energy-introducing arrangement comprises at least two energy-introducing ribs ( 23 ), which run approximately parallel to one another along the flange bottom side ( 200 ) and respectively project away from the flange bottom side ( 200 ) by a height (h).   
     
     
         2 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that the energy-introducing ribs ( 23 ) are arranged over a width (b) of about 2.5 to 2.7 mm which is less than or equal to the width of a bearing edge ( 61 ) of a sonotrode ( 6 ). 
     
     
         3 . The plastic closure device ( 1 ) as claimed in  claim 2 , characterized in that a flange top side ( 201 ), above the region in which the energy-introducing ribs ( 23 ) are arranged (b), is freely accessible. 
     
     
         4 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that respectively adjacent energy-introducing ribs ( 23 ) are arranged at a distance apart (b′) of 1 to 1.5 mm. 
     
     
         5 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that energy-introducing ribs ( 23 ), at their circumferential domes, are configured rounded with a radius (r) of 0.1 to 0.3 mm in cross section. 
     
     
         6 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that flanks of the energy-introducing ribs ( 23 ), which flanks are visible in cross section, enclose an angle (α) of 50° to 70°. 
     
     
         7 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that domes of the energy-introducing ribs ( 23 ) are configured to form, viewed in cross section, roughly punctiform bearing surfaces of the energy-introducing ribs ( 23 ). 
     
     
         8 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that the height (h) of the energy-introducing ribs ( 23 ) is between 0.2 and 0.4 mm. 
     
     
         9 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that the bottom side ( 200 ), in a marginal region (Y) adjoining an outer energy-introducing rib ( 23 ), is curved in a direction of a flange top side ( 201 ). 
     
     
         10 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that the energy-introducing arrangement comprises three energy-introducing ribs ( 23 ). 
     
     
         11 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that respectively adjacent energy-introducing ribs ( 23 ) are arranged at a distance apart (b′) of 1.25 mm. 
     
     
         12 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that flanks of the energy-introducing ribs ( 23 ), which flanks are visible in cross section, enclose an angle (α) of 60°. 
     
     
         13 . The plastic closure device ( 1 ) as claimed in  claim 1 , characterized in that the height (h) of the energy-introducing ribs ( 23 ) is 0.3 mm.