FR2660574A3 - Filter sleeve - Google Patents

Abstract

Filter sleeve made of nonwoven fabric conforming to food standards, especially made of viscose, provided with a lengthwise stitching. It is characterised in that edges (2) (3) of the filter sleeve (1) are brought together along the lengthwise stitching. One edge (3) is placed over another (2) with a certain width so that the latter edge (2) projects. The lengthwise stitching (4) is produced in the hem (5) parallel to the two edges (2) (3).

Description

 The invention relates to a filter sleeve, provided with a length seam of nonwoven, in particular viscose. The sleeve complies with food standards.

 Filtration sleeves of this type are well known. They are incorporated into the piping of milking machines. The milk sucked from the udder is pumped through filter sleeves. Immediately after milking, the milk is subjected to a first cleaning in which the filter sleeves serve as filters. These filtration sleeves are made of non-woven fabric (viscose), which complies with food standards. They are cut so as to be sewn by a length seam, along the edges.

 One drawback to these filter sleeves is that the piercing points of the seam come loose, especially if the seam is overloaded by the milk pumped under pressure through the filter sleeve. The seam piercing points, which extend over a distance of about 2.7 mm, then form unfiltered passage channels having a diameter of 1.5 mm to 2 mm. The margins placed end to end along the seam unstitch and then open a surface without filtering with a width of 23 mm, only fractionated by the mesh structure of the sewing threads. To avoid these drawbacks, the filter sleeves are welded along the length seam. However, this requires the addition of additional means for welding the filtering material. Such welded filter sleeves are more expensive and more difficult to manufacture.

 The objective of the invention is to improve the field of sewing and its position so that the open passage surfaces are considerably reduced while retaining the advantages of the sewn filter sleeve.

 To achieve this objective, according to the invention, the edges of the filter sleeves being joined along the seam, one edge is placed on another with a certain width so that the latter overflows and that the length seam is made in the flap parallel to the two edges.

 By this extraordinarily simple and therefore inexpensive measure, it is possible, while keeping the seam length, to manufacture a filtration sleeve having the same filtration qualities as a welded filtration sleeve.

 An advantageous development of the invention provides that the length seam is made in a zigzag.

Two embodiments of the invention are described more fully below with the aid of the attached drawings.
- Figure 1 shows an exemplary embodiment.

 - Figure 2 shows a cut along the line II-II in Figure 1.

 - Figure 3 shows, according to Figure 2, a second embodiment.

 Figure 1 shows a filtration sleeve according to the invention. This is installed in milking machines. Milk is pumped through. It is produced as indicated above, in non-woven material, that is to say in a material which allows the passage of milk and which at the same time guarantees the best filtration conditions.

 The filter sleeve 1 is sewn in one cut. The edge 3 envelops the edge 2 so that a flap 5 is formed. Sewing 4 is done through the flap. Figure 2 shows this in a partial cross section where the position of the seam is indicated by a dotted line. Figure 3 shows that the seam 4 can also be made in a zigzag shape.

 Thus, it is excluded that, by the effect of the pressure inside the filter sleeve, the seam will come loose and that instead of the seam, there will practically be a passage surface between the edges brought to an end. at the end. According to the invention, this surface is also covered with filtration material by the back of an edge, that is to say the edge 3 and therefore by the formation of a flap.

Claims (2)

 1. Non-woven filter sleeve, compliant with food standards, in particular viscose, provided with a length seam, characterized in that the edges (2) (3) of the filter sleeve (1) are gathered along the length seam, one edge (3) being placed on another (2) with a certain width so that the latter (2) projects and that the length seam (4) is made in the flap (5) parallel to the two edges (2) (3).  2. Filter sleeve according to claim 1, characterized in that the length seam (4) is made in a zigzag shape.