Spring in which inner middle ring and outer middle ring are matched with and connected to each other and elastic mattress

Abstract

A spring in which an inner middle ring and an outer middle ring are matched with and connected to each other includes a spring body, the inner middle ring, a flexible sleeve, and an outer middle ring. The inner middle ring is sleeved on the spring body and is at least spaced apart from a force-bearing end of the spring body for ¼ of a spring length of the spring. The flexible sleeve encloses the spring body and the inner middle ring, and the outer middle ring is buckled to the inner middle ring. An outer wall of the outer middle ring includes a connecting structure, and the spring and a second spring are connected together through the connecting structure.

What is claimed is: 
     
         1 . A spring in which an inner middle ring and an outer middle ring are matched with and connected to each other, comprising:
 a spring body,   the inner middle ring,   a flexible sleeve, and   the outer middle ring, wherein:
 the inner middle ring is sleeved on the spring body and is at least spaced apart from a force-bearing end of the spring body for ¼ of a spring length of the spring, 
 the flexible sleeve encloses the spring body and the inner middle ring, 
 the outer middle ring is buckled to the inner middle ring, 
 an outer wall of the outer middle ring comprises a connecting structure, and 
 the spring and a second spring are connected together through the connecting structure. 
   
     
     
         2 . The spring according to  claim 1 , wherein:
 an outer diameter of an upper end and a lower end of the inner middle ring gradually increases in a direction away from a middle part of the inner middle ring, and   a height of the outer middle ring is smaller than a height of the inner middle ring.   
     
     
         3 . The spring according to  claim 1 , wherein:
 an outer diameter of the spring body at a position at which the inner middle ring is connected to the spring body is smaller than an inner diameter of the inner middle ring.   
     
     
         4 . The spring according to  claim 1 , wherein:
 each end of the spring body is wound into a circle to form an end surface rings,   the spring body comprises at least one positioning ring, and the at least one positioning ring is a round ring of the spring body,   the at least one positioning ring is substantially parallel to at least one of the end surface rings or substantially perpendicular to an elastic force direction of the spring body, and   the inner middle ring is buckled to the at least one positioning ring.   
     
     
         5 . The spring according to  claim 4 , wherein
 a length of the at least one positioning ring is greater than or equal to ½ of a circumference of the at least one positioning ring.   
     
     
         6 . The spring according to  claim 1 , wherein:
 the inner middle ring is integrally formed on the spring body.   
     
     
         7 . The spring according to  claim 1 , wherein:
 at least one of the inner middle ring or the outer middle ring is formed by two to four arc-shaped members that are detachably clipped or buckled on a side of the spring body.   
     
     
         8 . The spring according to  claim 1 , wherein:
 the connecting structure and a second connecting structure of the second spring are connected together through a pin connection, a buckle connection, an insertion connection, or a position-limiting block fixing connection.   
     
     
         9 . The spring according to  claim 1 , comprising:
 a plurality of inner middle rings, including the inner middle ring; and   a plurality of outer middle rings, including the outer middle ring, wherein:
 a number of the plurality of outer middle rings is equal to a number of the plurality of inner middle rings. 
   
     
     
         10 . The spring according to  claim 2 , wherein:
 an outer diameter of the spring body at a position at which the inner middle ring is connected to the spring body is smaller than an inner diameter of the inner middle ring.   
     
     
         11 . The spring according to  claim 2 , wherein:
 each end of the spring body is wound into a circle to form an end surface rings,   the spring body comprises at least one positioning ring, and the at least one positioning ring is a round ring of the spring body,   the at least one positioning ring is substantially parallel to at least one of the end surface rings or substantially perpendicular to an elastic force direction of the spring body, and   the inner middle ring is buckled to the at least one positioning ring.   
     
     
         12 . The spring according to  claim 11 , wherein
 a length of the at least one positioning ring is greater than or equal to ½ of a circumference of the at least one positioning ring.   
     
     
         13 . An elastic mattress, comprising:
 an elastic layer, wherein:
 the elastic layer comprises a plurality of the springs according to  claim 1 . 
   
     
     
         14 . The elastic mattress according to  claim 13 , wherein:
 an outer diameter of an upper end and a lower end of the inner middle ring gradually increases in a direction away from a middle part of the inner middle ring, and   a height of the outer middle ring is smaller than a height of the inner middle ring.   
     
     
         15 . The elastic mattress according to  claim 13 , wherein:
 an outer diameter of the spring body at a position at which the inner middle ring is connected to the spring body is smaller than an inner diameter of the inner middle ring.   
     
     
         16 . The elastic mattress according to  claim 13 , wherein:
 each end of the spring body is wound into a circle to form an end surface rings,   the spring body comprises at least one positioning ring, and the at least one positioning ring is a round ring of the spring body,   the at least one positioning ring is substantially parallel to at least one of the end surface rings or substantially perpendicular to an elastic force direction of the spring body, and   the inner middle ring is buckled to the at least one positioning ring.   
     
     
         17 . The elastic mattress according to  claim 16 , wherein
 a length of the at least one positioning ring is greater than or equal to ½ of a circumference of the at least one positioning ring.   
     
     
         18 . The elastic mattress according to  claim 13 , wherein:
 the inner middle ring is integrally formed on the spring body.   
     
     
         19 . The elastic mattress according to  claim 13 , wherein:
 at least one of the inner middle ring or the outer middle ring is formed by two to four arc-shaped members that are detachably clipped or buckled on a side of the spring body.   
     
     
         20 . The elastic mattress according to  claim 13 , wherein:
 the connecting structure and a second connecting structure of the second spring are connected together through a pin connection, a buckle connection, an insertion connection, or a position-limiting block fixing connection.