Telescopic rail

Abstract

A telescopic rail has first, second, and third rail elements, and a drive device. The first and second rail elements are mounted together such that the first and second rail elements are linearly displaceable relative to one another in and counter to a pull-out direction. The third and second rail elements are mounted together such that the third and second rail elements are linearly displaceable relative to one another. The drive device, mounted on the first rail element, causes a linear movement of the second rail element relative to the first rail element. A traction element, fixed to the first and third rail elements, is guided on the second rail element parallel to the pull-out direction such that a displacement movement of the second rail element relative to the first rail element leads to a displacement movement of the third rail element relative to the second rail element.

1 . A telescopic rail ( 4 ) comprising
 a first rail element ( 1 ),   a second rail element ( 2 ),   a third rail element ( 3 ), and   a drive device ( 13 );   wherein the first rail element ( 1 ) and the second rail element ( 2 ) are mounted together such that the first rail element ( 1 ) and the second rail element ( 2 ) are linearly displaceable relative to one another in and counter to a pull-out direction ( 7 );   wherein the third rail element ( 3 ) and the second rail element ( 2 ) are mounted together such that the third rail element ( 3 ) and the second rail element ( 2 ) are linearly displaceable relative to one another in and counter to the pull-out direction ( 7 );   wherein the drive device ( 13 ) is mounted on the first rail element ( 1 ) or is mountable on a holding element connectable to the first rail element;   wherein the drive device ( 13 ) is configured such that, in an operation of the telescopic rail ( 4 ), the drive device ( 13 ) causes a linear movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) in or counter to the pull-out direction ( 7 );   wherein the telescopic rail ( 4 ) comprises a traction element ( 5 );   wherein the traction element ( 5 ) is fixed to the first rail element ( 1 ) and to the third rail element ( 3 );   wherein the traction element ( 5 ) is guided on the second rail element ( 2 ) in a direction parallel to the pull-out direction ( 7 ) such that a displacement movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) leads to a displacement movement of the third rail element ( 3 ) relative to the second rail element ( 2 ); and   the drive device is selected from a spindle drive, a tooth belt drive, a rack-and-pinion drive, a flexible shaft, a push rod, a push element, a traction element, a cable pull, a gas compression spring, a hydraulic or pneumatic cylinder, a receptacle for a linear motor, an electromagnetic linear drive, or a combination thereof.   
     
     
         2 . The telescopic rail ( 4 ) according to  claim 1 , characterized in that the second rail element ( 2 ) comprises a first guide element ( 10 ,  18 ) having a first deflection surface ( 21 ) and a second guide element ( 9 ,  17 ) having a second deflection surface ( 22 ),
 wherein the first guide element ( 10 ,  18 ) is configured such that a pulling force in the pull-out direction ( 7 ) can be transmitted from the second rail element ( 2 ) to the traction element ( 5 ) by means of the first guide element ( 10 ,  18 ),   wherein the second guide element ( 9 ,  17 ) is configured such that a pulling force counter to the pull-out direction ( 7 ) can be transmitted from the second rail element ( 2 ) to the traction element ( 5 ) by means of the second guide element ( 9 ,  17 ), and   wherein the traction element ( 5 ) is deflected by the first and second deflection surfaces ( 21 ,  22 ) such that a displacement movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) causes a transmission of a pulling force from the traction element ( 5 ) to the third rail element ( 3 ) in or counter to the pull-out direction.   
     
     
         3 . The telescopic rail ( 4 ) according to  claim 2 , characterised in that at least the first guide element ( 10 ,  18 ) or the second guide element ( 9 ,  17 ) comprises a pair of oppositely disposed traction element guide surfaces ( 23 ,  24 ) which face one another, wherein the traction element guide surfaces ( 23 ,  24 ) are configured such that they guide the traction element ( 5 ) in a direction perpendicular to the pull-out direction ( 7 ). 
     
     
         4 . The telescopic rail ( 4 ) according to  claim 2 , characterised in that at least the first guide element ( 10 ,  18 ) or the second guide element ( 9 ,  17 ) comprises a stationary holding portion ( 29 ) which is fixed to the second rail element ( 2 ) and a deflection portion ( 30 ) which is fixed to the holding portion ( 29 ) such that it can be moved in the pull-out direction ( 7 ), wherein the deflection portion ( 30 ) comprises the first and second deflection surfaces ( 21 ,  22 ) of the guide element ( 9 ,  17 ), and
 wherein the deflection portion ( 30 ) is resiliently pretensioned relative to the holding portion ( 29 ) in or counter to the pull-out direction ( 7 ) by means of a spring element ( 31 ), such that the traction element ( 5 ) is tensioned.   
     
     
         5 . The telescopic rail ( 4 ) according to any one of  claim 2  characterised in that at least the first or the second deflection surface ( 21 ,  22 ) is configured such that first or second deflection surface ( 21 ,  22 ) deflects the traction element by 180°, wherein the first or second deflection surface ( 21 ,  22 ) comprises a recess ( 25 ,  26 ), so that the traction element ( 5 ) is in frictional engagement with the first or second deflection surface ( 21 ,  22 ) over an angular range of less than 180°. 
     
     
         6 . The telescopic rail ( 4 ) according to the  claim 5 , characterised in that the traction element ( 5 ) comprises a latching projection ( 27 ) on a surface ( 28 ) which comes into frictional engagement with the first or second deflection surface ( 21 ,  22 ). 
     
     
         7 . The telescopic rail ( 4 ) according to  claim 2 , characterised in that the telescopic rail ( 4 ) comprises a rolling element cage with rolling elements received there-in and guided between the running surfaces of the second rail element ( 2 ) and the third rail element ( 3 ), wherein at least the first guide element ( 10 ,  18 ) or the second guide element ( 9 ,  17 ) forms a stop ( 35 ) for a movement of the rolling element cage ( 34 ) in or counter to the pull-out direction ( 7 ). 
     
     
         8 . The telescopic rail ( 4 ) according to  claim 2 , characterised in that the drive device is a spindle drive ( 13 ) comprising a threaded spindle ( 19 ) which is rotatable relative to the first rail element ( 1 ) and is stationarily mounted in the pull-out direction ( 7 ) and an internal thread ( 38 ) which is fixed on the second rail element ( 2 ) in the pull-out direction ( 7 ), wherein the internal thread ( 38 ) is mounted as a portion of a spindle nut ( 20 ) such that it floats in at least one direction perpendicular to the pull-out direction ( 7 ). 
     
     
         9 . The telescopic rail ( 4 ) according to  claim 8 , characterised in that the internal thread ( 38 ) is mounted as a portion of a spindle nut ( 20 ) in the first or second guide element ( 1 ,  2 ) such that it floats in at least one direction perpendicular to the pull-out direction ( 7 ) with a nut clearance, wherein the threaded spindle ( 19 ) is guided through the guide element ( 17 ,  18 ) in a spindle receiving bore ( 41 ), wherein the threaded spindle ( 19 ) in the spindle receiving bore ( 41 ) has a spindle clearance and wherein the spindle clearance is less than or equal to the nut clearance. 
     
     
         10 . The telescopic rail ( 4 ) according to  claim 8 , characterised in that the internal thread ( 38 ) is a portion of a spindle nut ( 20 ), wherein the spindle nut ( 20 ) comprises a torque arm which introduces torque transmitted from the threaded spindle ( 19 ) to the spindle nut ( 20 ) into the first or second guide element ( 17 ,  18 ). 
     
     
         11 . The telescopic rail ( 4 ) according to  claim 8 , characterised in that the spindle nut ( 20 ) is a clasp nut as an overload protection. 
     
     
         12 . The telescopic rail ( 4 ) according to  claim 1 , characterised in that the traction element ( 5 ) is configured in two parts with a first traction element portion ( 11 ) guided around the first guide element ( 10 ,  18 ) and a second traction element portion ( 12 ) guided around the second guide element ( 9 ,  17 ), wherein the first and the second traction element portion ( 11 ,  12 ) are respectively fixed on the first rail element ( 1 ) and the third rail element ( 3 ). 
     
     
         13 . The telescopic rail ( 4 ) according to  claim 1 , characterised in that the second rail element ( 2 ) comprises an axial bearing for the threaded spindle ( 19 ), wherein the axial bearing preferably comprises a bearing plate ( 42 ) bent out of a rail back of the first rail element ( 1 ). 
     
     
         14 . The telescopic rail ( 4 ) according to  claim 1 , characterised in that the traction element ( 5 ) is configured such that both pulling forces and pushing forces can be transmitted by means of the traction element ( 5 ), wherein the second rail element ( 2 ) comprises a guide element ( 17 ,  18 ), wherein the guide element ( 17 ,  18 ) is configured such that a pulling force and a pushing force can be transmitted from the second rail element ( 2 ) to the traction element ( 5 ) by means of the guide element ( 17 ,  18 ), and wherein the traction element ( 5 ) is deflected by the guide element ( 17 ,  18 ) such that both a pulling force acting on the traction element ( 5 ) and a pushing force acting on the traction element ( 5 ) causes a displacement movement of the third rail element ( 3 ) in or counter to the pull-out direction ( 7 ) relative to the second rail element ( 2 ). 
     
     
         15 . A pull-out assembly comprising a holding element, in particular a carcass, and a receiving element, in particular a drawer, which can be moved relative to the holding element, and two telescopic rails ( 4 ) which are disposed opposite to one another and with parallel pull-out directions ( 7 ) according to  claim 1 , wherein the first rail element ( 1 ) of each telescopic rail ( 4 ) is connected to the holding element and the third rail element ( 3 ) of each telescopic rail ( 4 ) is connected to the receiving element. 
     
     
         16 . A telescopic rail ( 4 ) comprising
 a first rail element ( 1 ),   a second rail element ( 2 ),   a third rail element ( 3 ), and   a drive device ( 13 );   wherein the first rail element ( 1 ) and the second rail element ( 2 ) are mounted together such that the first rail element ( 1 ) and the second rail element ( 2 ) are linearly displaceable relative to one another in and counter to a pull-out direction ( 7 );   wherein the third rail element ( 3 ) and the second rail element ( 2 ) are mounted together such that the third rail element ( 3 ) and the second rail element ( 2 ) are linearly displaceable relative to one another in and counter to the pull-out direction ( 7 );   wherein the drive device ( 13 ) is mounted on the first rail element ( 1 ) or is mountable on a holding element connectable to the first rail element;   wherein the drive device ( 13 ) is configured such that, in an operation of the telescopic rail ( 4 ), the drive device ( 13 ) causes a linear movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) in or counter to the pull-out direction ( 7 );   wherein the telescopic rail ( 4 ) comprises a traction element ( 5 );   wherein the traction element ( 5 ) is fixed to the first rail element ( 1 ) and to the third rail element ( 3 );   wherein the traction element ( 5 ) is guided on the second rail element ( 2 ) in a direction parallel to the pull-out direction ( 7 ) such that a displacement movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) leads to a displacement movement of the third rail element ( 3 ) relative to the second rail element ( 2 ); and   the drive device is selected from an elastic string drive, a chain drive, a belt drive, a flat belt drive, a V-belt drive, or a combination thereof.   
     
     
         17 . The telescopic rail ( 4 ) according to  claim 16 , characterized in that the second rail element ( 2 ) comprises a first guide element ( 10 ,  18 ) having a first deflection surface ( 21 ) and a second guide element ( 9 ,  17 ) having a second deflection surface ( 22 ),
 wherein the first guide element ( 10 ,  18 ) is configured such that a pulling force in the pull-out direction ( 7 ) can be transmitted from the second rail element ( 2 ) to the traction element ( 5 ) by means of the first guide element ( 10 ,  18 ),   wherein the second guide element ( 9 ,  17 ) is configured such that a pulling force counter to the pull-out direction ( 7 ) can be transmitted from the second rail element ( 2 ) to the traction element ( 5 ) by means of the second guide element ( 9 ,  17 ), and   wherein the traction element ( 5 ) is deflected by the first and second deflection surfaces ( 21 ,  22 ) such that a displacement movement of the second rail element ( 2 ) relative to the first rail element ( 1 ) causes a transmission of a pulling force from the traction element ( 5 ) to the third rail element ( 3 ) in or counter to the pull-out direction.   
     
     
         18 . The telescopic rail ( 4 ) according to  claim 17 , characterised in that at least the first guide element ( 10 ,  18 ) or the second guide element ( 9 ,  17 ) comprises a pair of oppositely disposed traction element guide surfaces ( 23 ,  24 ) which face one another, wherein the traction element guide surfaces ( 23 ,  24 ) are configured such that they guide the traction element ( 5 ) in a direction perpendicular to the pull-out direction ( 7 ). 
     
     
         19 . The telescopic rail ( 4 ) according to  claim 18 , characterised in that at least the first guide element ( 10 ,  18 ) or the second guide element ( 9 ,  17 ) comprises a stationary holding portion ( 29 ) which is fixed to the second rail element ( 2 ) and a deflection portion ( 30 ) which is fixed to the holding portion ( 29 ) such that it can be moved in the pull-out direction ( 7 ), wherein the deflection portion ( 30 ) comprises the deflection surface ( 21 ,  22 ) of the guide element ( 9 ,  17 ), and
 wherein the deflection portion ( 30 ) is resiliently pretensioned relative to the holding portion ( 29 ) in or counter to the pull-out direction ( 7 ) by means of a spring element ( 31 ), such that the traction element ( 5 ) is tensioned.   
     
     
         20 . A pull-out assembly comprising a holding element, in particular a carcass, and a receiving element, in particular a drawer, which can be moved relative to the holding element, and two telescopic rails ( 4 ) which are disposed opposite to one another and with parallel pull-out directions ( 7 ) according to  claim 16 , wherein the first rail element ( 1 ) of each telescopic rail ( 4 ) is connected to the holding element and the third rail element ( 3 ) of each telescopic rail ( 4 ) is connected to the receiving element.