Spring core

Abstract

A spring core includes a plurality of helically wound springs. At least two of the springs include a bulging at least at one of two end regions of each of the at least two springs in a direction of a longitudinal axis of the at least two springs.

1 . A spring core comprising: 
 a plurality of helically wound springs; and    at least two of the plurality springs include a bulging at least at one of two end regions of each of the at least two springs in a direction of a longitudinal axis of the at least two springs.    
   
   
       2 . The spring core according to  claim 1 , wherein both end regions of the at least two springs include a throat formed between the bulgings.  
   
   
       3 . The spring core according to  claim 1 , wherein pitches of the windings of at least two springs are one of identical and different in the end regions of the at least two springs.  
   
   
       4 . The spring core according to  claim 3 , wherein the pitch of the windings of the end regions is one of flatter and steeper, and in a direction of the a throat formed between the bulgings the pitch of the windings is one of steeper and flatter.  
   
   
       5 . The spring core according to  claim 1 , wherein the at least two springs are mutually connected by a spiral wire.  
   
   
       6 . The spring core according to  claim 1 , wherein the at least two springs are constructed as pocket springs.  
   
   
       7 . The spring core according to  claim 6 , wherein a row of the pocket springs are connected to form a spring strand.  
   
   
       8 . The spring core according to  claim 7 , wherein the spring strand is glued together with an adjacent spring strand in the end region of a bulging of individual pocket springs.  
   
   
       9 . The spring core according to  claim 8 , wherein an elastic intermediate layer is arranged between two of the spring strands.  
   
   
       10 . The spring core according to  claim 9 , wherein the intermediate layer includes a foamed material.  
   
   
       11 . The spring core according to  claim 9 , wherein the intermediate layer is glued together with the one of the pocket springs and the spring strands.  
   
   
       12 . The spring core according to  claim 1 , wherein a spring which differs from the at least two springs is inserted into a space formed by the at least two springs.  
   
   
       13 . The spring core according to  claim 12 , wherein the different spring is constructed as a barrel spring.  
   
   
       14 . The spring core according to  claim 13 , wherein the barrel spring rests in a throat of one of the at least two springs.  
   
   
       15 . The spring core according to  claim 13 , wherein the barrel spring projects over the at least two springs on one end of the at least two springs.  
   
   
       16 . The spring core according to  claim 13 , wherein at least one of the at least two springs in their entirety and the barrel springs are each mutually connected by a cover layer.  
   
   
       17 . The spring core according to  claim 5 , wherein the spiral wire connecting the at least two springs is in the form of a Bonell spring core.