Device for regulating the movement of the folding seat of a chair

Abstract

A device for allowing the regulation of the movement of the folding seat of a chair applied on one chair or several chairs of the type called “with a bar”. The device includes a boxed body which contains in its interior a group of articulated lever devices which regulate the motion of the folding seat between horizontal and vertical positions.

What is claimed is:  
     
         1 . A device for regulating the motion of the folding seat of a chair, said device being applied to single chairs or chairs called “with a bar” used in theaters, stadiums and in general in rooms used for meetings, said device tending to keep said seat in the vertical position, said device comprising a boxed body anchored to the bar supporting the aligned chairs, said body containing in its interior at least one group of articulated lever devices attached at one extremity on the body itself and at the other extremity on the base of said folding seat, said group of articulated lever devices being composed of two levers, which are reciprocally arranged side-by-side and are fitted at one extremity in a neutral mode on two pins, said pins being integral with said boxed body, the other extremities of said two levers being hinged on two pins, said pins constituting also the point of articulation of the bracket which supports the folding seat.  
     
     
         2 . The device according to  claim 1 , which comprises an elastic element which provides for carrying out a force opposite to the force which allows the lowering of the seat and which operates in the direction to dispose said seat in an essentially vertical manner.  
     
     
         3 . The device according to  claim 1  wherein said folding seat ( 2 ) and the back ( 3 ) are applied on said device, said device being clamped by means of clamp ( 4 ) to said transversal bar ( 5 ), wherein said device is constituted by a boxed body ( 6 ) in the interior of which are placed two groups of articulated lever devices ( 7 ), said groups being symmetrically disposed, each group of said articulated lever devices comprising two levers ( 9 ,  10 ) which are parallel and hinged at one extremity in a neutral mode on two fixed pins ( 11 ,  12 ), said pins being blocked on said boxed body, the other extremities of said levers being hinged on pins ( 13 ,  14 ), said pins functioning also for double articulation of the bracket ( 15 ) which supports said folding seat.  
     
     
         4 . The device according to  claim 3 , wherein said four pins ( 11 ,  12 ,  13 ,  14 ) which have parallel axes, are disposed in such a manner that when seat ( 2 ) is completely raised, one of said levers ( 9 ) of each group becomes hooked with its notch ( 16 ) on pin ( 13 ) of said two articulation pins.  
     
     
         5 . The device according to  claim 4 , wherein when the seat ( 2 ) is completely lowered, lever ( 10 ) of each group is placed with its base ( 17 ) on said articulation pin ( 14 ).  
     
     
         6 . The device according to  claim 5 , wherein the action opposite to the lowering of the seat ( 2 ) is ensured by means of the opposite force carried out by means of a spiral spring ( 8 ), said spring being wound on a fixed pin ( 12 ), a first extremity ( 18 ) being in contact with the base ( 19 ) of the boxed body ( 6 ), and a second extremity being disposed against the articulation pin ( 13 ).