Method and device for producing a toothbrush by the two-component or multi-component injection-molding process

Abstract

The invention relates to a method and a device for producing a toothbrush or part thereof by the two-component or multi-component injection-molding process. To produce in the brush body segments that are isolated from the rest of the brush body, a mold which comprises three hollow regions is used. Two of these hollow regions that are separate from one another serve for producing the segments and the other regions of the toothbrush from a first component. A third hollow region serves for distributing material to the segments that are isolated from one another and from the other regions, or the corresponding hollow region. The material remaining behind there is removed and sent for disposal. In a further step, connecting elements between the segments and/or the other regions are injection-molded from a second component.

1 . A method for producing a toothbrush with a body which comprises at least a handle region, a neck region and a head region and a carrier element connected to the body, with the following steps:
 producing a plurality of segments in a form of sleeves or cups as well as other regions of the carrier element of a first component in a first step;   producing connecting elements in a form of a membrane by injection of a second component in a further step, said connecting elements connecting the segments and the other regions of the carrier element;   thereafter fitting the carrier element with bristles; and   connecting the carrier element including the bristles to a separately produced body.   
     
     
         2 . The method as claimed in  claim 1 , wherein the segments are molded into an elliptical or kidney shaped form or in the form of a figure of eight. 
     
     
         3 . The method as claimed in  claim 1 , wherein the head region has an edge onto which an outer edge of the carrier element comes to bear whereby the carrier element and the brush body will be connected undetachably along a line. 
     
     
         4 . The method as claimed in  claim 3 , wherein the head region and the carrier element are welded along said line producing a welding area, said welding area being partially disrupted by openings or different material components. 
     
     
         5 . The method as claimed in  claim 1 , wherein the carrier element is connected to the head region of the body under prestress in such a way that it is made to arch up. 
     
     
         6 . The method as claimed in  claim 1 , wherein the first component is a hard component and the second component is a hard or a soft component. 
     
     
         7 . The method as claimed in  claim 6 , wherein the hard component comprises at least one of of styrene-acrylonitrile (SAN), polyethylene terephthalate (PET), polyethylene (PE), polymethylmethacrylate (PMMA), acrylobutadiene styrene (ABS) and polypropylene (PP). 
     
     
         8 . The method as claimed in  claim 6 , wherein the soft-component consists of a rubber-elastic material. 
     
     
         9 . The method as claimed in  claim 1 , wherein a spatial position of the segments in relation to at least one of one another and the other regions is changed before the injection-molding of the second component. 
     
     
         10 . The method as claimed in  claim 1 , the fitting the carrier element with bristles further comprises:
 leading a bristle cluster through an opening in the carrier element; and   then melting the bristle cluster at the rear end to connect the bristle cluster to the carrier element.   
     
     
         11 . The method as claimed in  claim 10 , wherein the bristle cluster is led through an opening of a segment. 
     
     
         12 . The method as claimed in  claim 1 , wherein cleaning and massaging elements are formed by the second component. 
     
     
         13 . Toothbrush with a body comprising at least a handle region, a neck region and a head region, wherein the body at least partially comprises a first and a second component, and a carrier element comprising a plurality of segments and other regions of a first component and a membrane of the second component connecting the segments and the other regions, wherein the head region is connected to other regions of the first component of the carrier element and the carrier element holds bristles. 
     
     
         14 . Toothbrush as claimed in  claim 13 , wherein the other regions of the first component form an elliptical closed periphery onto which sleeves are directly molded, in the head region a circular edge is formed against which an outer edge of the carrier element bears, and, along a line formed by the edge and the outer edge, the carrier element is undetachably connected to the body. 
     
     
         15 . Toothbrush as claimed in  claim 13 , wherein the other regions of the first component form two material pieces, the head region has two edges running in a transverse direction and serving as anchoring locations for the carrier element and the two material pieces are fastened to the two edges, respectively. 
     
     
         16 . Toothbrush as claimed in  claim 13 , wherein
 the body is (1) bent in the head region, and (2) branched one or more times toward a front end to form a skeletal carrying structure with an anchoring location formed at an end of each branch,   a further anchoring location is built on the body in the form of an elongate edge at a transition from the head region to the neck region,   the carrier element has an elongate material piece at one end and plate-like pieces that are distributed in a manner to correspond to at least one anchoring location, the membrane is located between the olongate material piece and the plate-like material pieces, and   the elongate material piece and the plate-like material pieces form the other regions of the first component.   
     
     
         17 . Toothbrush as claimed in  claim 13 , wherein the segments have a form of at least one of singular and interconnected sleeves or cups, which are adapted to receive bristle clusters. 
     
     
         18 . Toothbrush as claimed in  claim 17 , wherein the segments have an opening,the opening having a shape that is at least one of elliptical, circular,kidney shaped and in the form of a figure eight. 
     
     
         19 . Toothbrush as claimed in  claim 13 , further comprising at least one of cleaning and massaging elements of the second component. 
     
     
         20 . A device for carrying out the method as claimed in  claim 1 , the device comprising:
 a first mold including:
 first hollow regions, which correspond to the other regions to be produced from the first component and to which the first component can be supplied, 
 second hollow regions, which are arranged at a distance from one another and correspond to the segments to be produced from the first component, and 
 at least one third hollow region, to which the first component can be supplied and which is connected with the second hollow regions in such a way that material supplied to the at least one third hollow region is supplied to the second hollow regions, 
 wherein the second hollow regions for producing a plurality of segments that are separate from one another comprise a plurality of subregions, which are in connection with one another exclusively via the at least one third hollow region; 
   a second mold, including:
 a fourth hollow region which is larger than the second hollow regions, at least in the region around the segments, 
 wherein the second mold is shaped such that it is adapted to the first mold in such a way that connecting elements are formed from the second component as a membrane, in which the segments are at least partially embedded and which is resiliently connected to the other regions of the first component; and 
   means for removing the first mold at least partially in such a way that the at least one third hollow region, including solidified material remaining in the at least one third hollow region, is removed from the segments and the other regions of the toothbrush.   
     
     
         21 . A device as claimed in  claim 20 , further comprising means for introducing the segments and the other regions into the second mold. 
     
     
         22 . A device as claimed in  claim 20 , wherein the second hollow regions are shaped in such a way that the segments have the form of sleeves that are open at two ends, through which bristles can be led, the opening directions being oriented substantially perpendicularly in relation to a surface area of the head region. 
     
     
         23 . A device as claimed in  claim 20 , wherein the first mold comprises at least three part-molds, the first and second hollow regions being formed between a first part-mold and a second part-mold and the at least one third hollow region being formed between the second part-mold and a third part-mold. 
     
     
         24 . A device as claimed in  claim 20 , further comprising a handling unit for changing at least one of a position and an orientation of the segments in relation to one another before the second component is injected. 
     
     
         25 . The method as claimed in  claim 8 , wherein the rubber-elastic material is a thermoplastic elastomer (TPE). 
     
     
         26 . The method as claimed in  claim 25 , wherein the thermoplastic elastomer is polyurethane (PUR). 
     
     
         27 . The method as claimed in  claim 9 , wherein the spatial position of the segments is changed through at least one of translation and rotation. 
     
     
         28 . The method as claimed in  claim 12 , wherein the cleaning and massaging elements are connected to the membrane. 
     
     
         29 . The method as claimed in  claim 28 , wherein the cleaning and massaging elements are produced in a same production step as the membrane. 
     
     
         30 . Toothbrush as claimed in  claim 14 , wherein the carrier element is connected to the body by welding. 
     
     
         31 . Toothbrush as claimed in  claim 15 , wherein the two material pieces are fastened to the two edges by welding. 
     
     
         32 . Toothbrush as claimed in  claim 19 , wherein the cleaning and massaging elements are connected to the membrane. 
     
     
         33 . Toothbrush as claimed in  claim 32 , wherein the cleaning and massaging elements are produced in a same production step as the membrane.