Needling device for consolidating a fibre fleece

Abstract

Needles ( 47 ) periodically penetrate into a needling path ( 1 ) between a stripper plate ( 26 ) and a needling table ( 24 ). In the process, the needles describe an elliptical movement by means of which they accompany the textile when they are in penetration phase. The elliptical movement is generated by oscillating-sliding of a rod ( 38 ) in a rotating guide ( 39 ). The rod ( 38 ) is actuated by two crank connecting-rod systems ( 51 a, 51 b ), the adjustable phase shifting of which defines the horizontal amplitude of the movement of the needles. Use for simplifying elliptical guiding means, reducing plays and air turbulences.

1 . An apparatus ( 3 ) for needling or pre-needling a fleece to be processed, comprising a movable structure ( 36 ,  136 ) intended to carry needles ( 47 ), and an actuating mechanism for imparting to the needles ( 47 ) an elliptical-type movement having a penetration component and a progression component, characterized in that one of the components, preferably the progression component, is at least to a large extent generated by angular oscillation of the movable structure.  
     
     
         2 . Apparatus according to  claim 1 , characterized in that the elliptical-type movement of the needles takes place along a trajectory (T) comprising a proximal part (TP) directed towards the fleece and along which the progression component is in the direction ( 6 ) of progressive movement of the fleece, and a distal part (TD) along which the progression component is in the direction opposite to the direction of progression of the fleece, the proximal part (TD) being greater than the distal part (TD) when the proximal (TP) and distal (TD) parts are measured parallel to the penetration component of the movement of the needles.  
     
     
         3 . Apparatus according to  claim 1 , characterized in that the movable structure ( 36 ,  136 ) is guided relative to a frame of the machine by a functional chain comprising a sliding in series with an articulation about an axis ( 37 ,  137 ) parallel to the width of the fleece of fibres.  
     
     
         4 . Apparatus according to  claim 3 , characterized in that the sliding and the articulation are carried out by means arranged inside one another.  
     
     
         5 . Apparatus according to  claim 1 , characterized in that the movable structure ( 36 ) is slidingly guided by a guide ( 39 ) mounted for angular oscillation.  
     
     
         6 . Apparatus according to  claim 5 , characterized in that the actuating mechanism comprises two crank connecting-rod systems, each system comprising a connecting rod ( 51   a,    51   b ) a small end of which ( 54   a,    54   b ) is at least indirectly linked to said movable structure ( 36 ) by an articulation about a so-called positioning axis ( 56   a,    56   b ) which is parallel to said oscillation axis ( 37 ).  
     
     
         7 . Apparatus according to  claim 6 , characterized in that the two crank connecting-rod systems are similar and capable of a phase shift (φ), one being situated ahead of and the other behind the positioning axis ( 56   a,    56   b ), relative to the direction of progression ( 6 ) of the fleece.  
     
     
         8 . Apparatus according to  claim 6 , characterized in that there is an adjustable phase shift (φ) between the two crank connecting-rod systems.  
     
     
         9 . Apparatus according to  claim 8 , characterized in that a differential gear ( 71 ) mounted operatively between the two crank connecting-rod systems comprises a planet gear ( 74   a ) carried by a case ( 78 ) having an adjustable fixed angular position.  
     
     
         10 . Apparatus according to  claim 8 , characterized by a common motor ( 72 ) for the two crank connecting-rod systems and a clutch ( 401 ) mounted operatively between one of the crank connecting-rod systems and a drive member ( 73 ) which is common to the two crank connecting-rod systems.  
     
     
         11 . Apparatus according to  claim 7 , characterized in that each crank connecting-rod system comprises a balancing counterweight ( 301   a,    301   b ) associated with its crank, and in that an angular deviation between counterweight and connecting-rod big-end axis about the crank axis exhibits a difference (δ) between the two crank connecting-rod systems.  
     
     
         12 . Apparatus according to  claim 11 , characterized in that the angular deviation difference (δ) is such that the two counterweights ( 301   a,    301   b ) are becoming closer and closer to a state of symmetry with each other relative to a plane transverse to the path of the fleece when the phase shift (φ) is caused to increase, at least in a first range of variation starting from a zero phase shift.  
     
     
         13 . Apparatus according to  claim 6 , characterized in that there is a respective positioning axis ( 56   a,    56   b ) for each of the two crank connecting-rod systems.  
     
     
         14 . Apparatus according to  claim 13 , characterized in that the two positioning axes ( 56   a,    56   b ) have a very small centre-to-centre distance (e).  
     
     
         15 . Apparatus according to  claim 6 , characterized in that two crank axes ( 49   a,    49   b ) of the two crank connecting-rod systems form with the two connecting-rod-small-end axes ( 54   a,    54   b ) two centre-distance lines ( 60   a,    60   b ) having between them an angle (A) very different from 0° and from 180°, having a vertex preferably situated in the vicinity of the two connecting-rod small-end axes, preferably a short distance beyond said small-end axes.  
     
     
         16 . Apparatus according to  claim 6 , characterized in that the two connecting rods ( 51   a,    51   b ) are oriented with their connecting-rod small end ( 54   a,    54   b ) pointing in a direction generally away from the plane ( 1 ) of the fleece ( 41 ).  
     
     
         17 . Apparatus according to  claim 6 , characterized in that the guide ( 39 ) is placed substantially between two eccentric means ( 48   a,    48   b ) turning in mutually opposite directions and each forming part of respective one of the two crank connecting-rod systems.  
     
     
         18 . Apparatus according to  claim 5 , characterized in that, along a sliding direction defined by the guide ( 39 ), said guide is placed between the needles ( 47 ) on the one hand and the coupling of the movable structure ( 36 ) to the actuating mechanism on the other hand.  
     
     
         19 . Apparatus according to  claim 18 , characterized in that said apparatus comprises means, forming a lubricating-oil barrier, through which the movable structure ( 36 ) passes in the vicinity of the guide ( 39 ).  
     
     
         20 . Apparatus according to  claim 3 , characterized in that the movable structure ( 136 ) is articulated by said articulation to a slider ( 17 ) actuated by a first reciprocation generator, in particular a crank connecting-rod system ( 31 ,  127 ), generating one of the components, preferably the penetration component, and the movable structure ( 136 ) is also articulated about a positioning axis ( 156 ) to a second crank connecting-rod system ( 94 ,  98 ) generating said angular oscillation of the movable structure ( 136 ) about said articulation to the slider ( 17 ).  
     
     
         21 . An apparatus for needling a non-woven material with at least one needle bar which is drivable in a reciprocating manner by at least one eccentric drive in the needle-penetration direction, which needle bar is linked to the eccentric drive via oscillating sliding rods each displaceably held in a bore of a guide, which eccentric drive consists of two parallel eccentric shafts which are drivable in opposite directions and are provided with connecting rods, with the guides being pivotably held about an axis extending parallel to the eccentric shafts, characterized in that the two eccentric shafts are provided with a different angular position and that the connecting rods of the two eccentric shafts extend in an inclined manner with respect to each other.  
     
     
         22 . An apparatus as claimed in  claim 21 , characterized in that the two eccentric shafts are adjustable in their mutual angular position.