Self-shaping earplugs

Claim 2

An earplug substantially in the shape of a dumbbell comprising a resilient and elastic envelope having first and second expansible hollow cavity portions at either end connected together through a commissure, a plastic filler material positioned within the envelope and having the property of slowly flowing between cavity portions through the commissure upon the squeezing of one of the cavity portions, said plastic fiLler material also being relatively unyielding to oscillatory acoustic pressures but slowly flowing under relatively sustained pressures so that one of the cavity portions may be compressed and remain so for a time sufficient to permit insertion into the ear canal of a user, one of said cavity portions expanding by acceptance after compression of the other of said cavity portions a more than initial amount of filler material therein and then slowly driving the filler material back through the commissure into the previously compressed cavity portion as the expanded cavity elastically attempts to return to its initial dimensions to expand the previously compressed cavity portion and a stiffening member which forms the major axis of the earplug and is coupled to the envelope portions forming said first and second cavity portions, said stiffening member being sufficiently stiff along its length to transmit an inserting force to insert the earplug into the ear canal.

Claim 3

An earplug according to claim 1 in which the stiffening member is at least in part surrounded by the envelope.

Claim 4

An earplug according to claim 2 in which the stiffening member is a tube.

Claim 5

An earplug according to claim 2 in which viscous liquid or grease is provided in the hollow portions of the tube to obstruct the passage of audible sound through said hollow tube while permitting an equalization of static air pressure at either end of said tube.

Claim 6

An earplug according to claim 1 in which the filler is a silicone putty.

Claim 7

An earplug according to claim 2 in which the stiffening member is a rod.

Claim 8

An earplug according to claim 2 in which the stiffening member is a tube or a rod and is constructed of a foamed plastic.

Claim 9

An earplug according to claim 1 in which the stiffening member includes bulging portions at either end thereof.

Claim 10

An earplug according to claim 1 in which the filler is a flowable plastic silicone compound.

Claim 11

An earplug for use by a user comprising a resilient and elastic envelope which assumes a dumbbell shape when unstressed, said envelope having an expansible hollow cavity portion at each end with a narrow connecting neck portion therebetween, an elongate stiffening member which extends axially through said neck and is coupled to said dumbbell shaped envelope substantially at each end thereof and a soft slowly flowing plastic filler material within said envelope, said plastic filler material being relatively unyeilding to oscillatory acoustic pressures but flowing under sustained pressures so that one of said cavity portions which is to be inserted into the user''s ear canal can be compressed, thereby displacing the corresponding portion of said plastic filler material through said neck portion and into the other elastic cavity portion which is constructed to expand outside of the user''s ear canal under the pressure of said plastic filler material thereby permitting the compressed portion to be essentially pulled into the user''s ear canal by said stiffening member and subsequently the elastic tension of the stretched envelope of the cavity portion outside of the ear canal will drive said plastic filler material back into the cavity portion within the ear canal, thereby establishing a substantial area of uniform compressive contact between that portion of the earplug and the interior of the user''s ear canal.

Claim 12

An earplug for use by a user comprising a resilient and elastic envelope which assumes a dumbbell shape when unstressed, said envelope having an expansible hollow cavity portion at each end with a narrow connecting neck portion therebetween, an elongate stiffening member which extends axially through said neck and is coupled to said dumbbell shaped envelope substantially at each end thereof and a soft slowly flowing plastic filler material within said envelope, said plastic filler material being relatively unyeilding to oscillatory acoustic pressures but flowing under sustained pressures so that one of said cavity portions which is to be inserted into the user''s ear canal can be compressed, thereby displacing the corresponding portion of said plastic filler material through said neck portion and into the other elastic cavity portion which is constructed to expand outside of the user''s ear canal under the pressure of said plastic filler material thereby permitting the compressed portion to be essentially pulled into the user''s ear canal by said stiffening member and subsequently the elastic tension of the stretched envelope of the cavity portion outside of the ear canal will drive said plastic filler material back into the cavity portion within the ear canal, thereby establishing a substantial area of uniform compressive contact between that portion of the earplug and the interior of the user''s ear canal.

Claim 13

An earplug according to claim 10 in which the filler material is a flowable plastic silicone compound.

Claim 14

An earplug according to claim 10 in which the stiffening member is a tube.

Claim 15

An earplug according to claim 11 in which the filler material is silicone putty.

Claim 16

An earplug according to claim 13 in which the cavity portions each have a diameter D2 and wherein the neck portion has a diameter D1 at its narrowest cross-section and wherein D1 0.5 to 0.8 D1.