Coil spring for bed mattress having means for preventing frictional noise

Abstract

A coil spring for a bed mattress. At least one of contact wiring portions 16 - 5 and 16 - 5 ′ of the upper and lower exposed wiring portions 16 and 16 ′ which abut to the end wiring portions 14 while the upper and lower exposed wiring portion 16, 16 ′ are being compressed has a contact surface A which is in contact with one corresponding end wiring portion of the end wiring portions 14 , whereby frictional noise between the exposed wiring portion 16, 16 ′ and the end wiring portion 14 is prevented. It is possible to consequently remove friction that is created due to contact between the exposed wiring portion and the end wiring portion while the exposed portion is being compressed, thereby preventing noise. The exposed wiring portion and the body wiring portion move only upward and downward without being displaced or deformed in the lateral direction, thereby increasing longevity.

What is claimed is: 
     
         1 . A coil spring for a bed mattress having means for preventing frictional noise which includes a body wiring portion situated in a space between an upper edge member and a lower edge member, and an end wiring portion provided on both ends of the body wiring portion and set within a range in which the upper and lower edge members are disposed, and at least one of an upper exposed wiring portion extending from the end wiring portion so as to be exposed from the upper edge member and a lower exposed wiring portion extending from the end wiring portion so as to be exposed from the lower edge member,
 wherein at least one of contact wiring portions of the upper and lower exposed wiring portions which abut to the end wiring portions while the upper and lower exposed wiring portion are being compressed has a contact surface which is in contact with one corresponding end wiring portion of the end wiring portions, whereby frictional noise between the exposed wiring portion and the end wiring portion is prevented.   
     
     
         2 . A coil spring for a bed mattress having means for preventing frictional noise which includes a body wiring portion situated in a space between an upper edge member and a lower edge member, end wiring portions provided on both ends of the body wiring portion and set within a range in which the upper and lower edge members are disposed, and at least one of an upper exposed wiring portion extending from the end wiring portion so as to be exposed from the upper edge member and a lower exposed wiring portion extending from the end wiring portion so as to be exposed from the lower edge member,
 the coil spring further comprising at least one rigid support end which is provided on the body wiring portion or the upper or lower exposed wiring portion so as to absorb a compressive load,   wherein at least one of contact wiring portions of the upper and lower exposed wiring portions which abut to the end wiring portions while the upper and lower exposed wiring portions are being compressed has a contact surface which is in contact with one corresponding end wiring portion of the end wiring portions, whereby frictional noise between the exposed wiring portion and the end wiring portion is prevented.   
     
     
         3 . The coil spring according to  claim 3 , wherein the rigid support end is formed at a right angle or an acute angle with respect to the end wiring portion.