Method and device for pneumatically spreading an elongated flexible article, such as a stocking or a sock

Abstract

The device comprises: a suction duct ( 7 ) with a first end and a second end; a retaining member ( 5 ) to hold a flexible article (M) inserted at least partly in said suction duct; and a suction opening ( 21 ) which places the inside of the suction duct in communication with the outside, arranged in an intermediate position between the retaining member and the second end.

1 . A device for spreading a flexible and elongated article, such as a sock or stocking, the device comprising:
 a suction duct with a first end and a second end;   a retaining member to hold a flexible article at least partly inserted in said suction duct;   a suction opening that puts the inside of the suction duct in communication with the outside, said suction opening being arranged in an intermediate position between said retaining member and said second end; and   a suction source in fluid communication with said second end.   
     
     
         2 . A device as claimed in  claim 1 , wherein said suction opening has an opening and closing valve. 
     
     
         3 . A device as claimed in  claim 2 , wherein said opening and closing valve is controlled such that said opening and closing valve is in an open position when said article is inserted inside said suction duct. 
     
     
         4 . A device as claimed in  claim 1 , wherein said suction duct comprises two portions inclined with respect to each other. 
     
     
         5 . A device as claimed in  claim 4 , wherein a connecting section is disposed between said two inclined portions, said suction opening being arranged in one of said two portions, said retaining member being associated with said one of said two portions, said second end being positioned in another of said two portions. 
     
     
         6 . A device as claimed in  claim 1 , wherein an element is associated with said first end of the suction duct, said element modifying a cross section of the suction duct. 
     
     
         7 . A device as claimed in  claim 6 , wherein said element comprises a block with a shape corresponding to an inner wall ofthe suction duct, said block being inserted transversely in said suction duct such that the cross section of said duct is reduced and a transverse passage with a narrow and elongated section is formed, wherein said retaining member is controlled and arranged such that said retaining member moves in a direction opposite the suction air flow to extract the article, the article passing through said narrow and elongated section when said retaining member moves in said direction opposite the suction air flow. 
     
     
         8 . A method for spreading a flexible and elongated article, the method comprising:
 inserting at least a portion of an article in a suction duct; and   holding the article such that said portion ofthe article is maintained in said suction duct;   generating an air flow is in said suction duct, said air flow being drawn by suction at least partly through an intermediate suction opening provided in a wall of the suction duct.   
     
     
         9 . A method as claimed in  claim 8 , further comprising the steps of:
 disposing said article at least partly in said suction duct such that said article is not drawn by the air flow;   opening said intermediate opening such that said air flow is generated from the outside in a direction of an interior of the suction duct, said flow engaging said portion of the article located in the suction duct.   
     
     
         10 . A method as claimed in  claim 8 , wherein the article is gradually extracted from the suction duct with a movement in a direction opposite to the direction of said air flow. 
     
     
         11 . A method as claimed in  claim 10 , wherein said article passes through a narrow and elongated cross section such that the article is flattened transversely with respect to a direction of the extraction movement and a longitudinal extension thereof. 
     
     
         12 . A device as claimed in  claim 2 , wherein said suction duct comprises two portions inclined with respect to each other. 
     
     
         13 . A device as claimed in  claim 3 , wherein said suction duct comprises two portions inclined with respect to each other. 
     
     
         14 . A device as claimed in  claim 12 , wherein a connecting section is disposed between said two inclined portions, said suction opening being arranged in one of said two portions, said retaining member being associated with said one of said two portions, said second end being positioned in another of said two portions. 
     
     
         15 . A method as claimed in  claim 9 , wherein the article is gradually extracted from the suction duct with a movement in a direction opposite to the direction of said air flow. 
     
     
         16 . A method as claimed in  claim 15 , wherein said article passes through a narrow and elongated cross section such that the article is flattened transversely with respect to a direction of the extraction movement and a longitudinal extension thereof.