Length adjustable earplug cord
A cord-earplug set ( 10 ) which includes a cord ( 16 ) that connects together a pair of earplugs ( 12, 14 ), the cord having a length that can be readily increased by a worker who pulls apart the opposite ends of the cord. The cord has an initial length much less than the usual two feet, such as 11 to 14 inches, and is constructed so the cord can be stretched by a worker pulling apart the cord ends with a force on the order of magnitude of 15 pounds. The cord is preferably formed of an elastomeric polymer of uniform diameter along its length so when the cord ends are pulled apart (by pulling apart the earplugs) to stretch the cord, the cord sections lengthen evenly to leave a cord of approximately constant diameter along its length.
1 . A cord-earplug set which includes a pair of earplugs that each has front and rear ends, and a flexible cord that extends between rear ends of said earplugs so the cord can extend behind a person in its extension between said earplug rear ends, wherein:
said cord is permanently stretchable by more than an inch by a tension force on the order of magnitude of fifteen pounds.
2 . The cord-earplug set described in claim 1 wherein:
said cord has an initial length of no more than 16 inches.
3 . The cord-earplug set described in claim 1 wherein:
said cord has an initial length of about 11 inches.
4 . The cord-earplug set described in claim 1 wherein:
said cord is formed of elastomeric material and is of uniform material and diameter along its length between the rear ends of said earplugs.
5 . A cord-earplug set which includes a pair of earplugs that each has front and rear ends, and a flexible cord that extends between rear ends of said earplugs so the cord can extend behind a person in its extension between said earplug rear ends, wherein:
said cord has an initial length of no more than about 16 inches, but is permanently stretchable by at least an inch by an average wearer pulling apart opposite end portion of the cord using only the wearer's hands.
6 . The cord-earplug set described in claim 5 wherein:
said earplug is formed of elastomeric material.
7 . A method for producing a cord-earplug set and adjusting it to an individual, where the cord-earplug set includes a pair of earplugs that each has front and rear end portions, and also includes a flexible cord that extends between said rear ends of said earplugs, comprising:
constructing said cord with an initial length and with a construction that makes the cord permanently stretchable by more than 25% of its initial length by a pull force on the order of magnitude of 15 pounds.
applying a stretching tension to said cord and stretching it so it is permanently stretched by at least 10% of its initial length.
8 . The method described in claim 7 wherein said steps of constructing includes inserting ends of said cord into said earplug rear portions, and wherein:
said step of applying a stretching tension includes grasping and squeezing the rear end of each of said earplugs, to prevent cord pullout therefrom, while pulling apart said earplugs to stretch said cord.