US2785676A - Ear protecting device - Google Patents

Description

,March 19, 1957 B. BERKMAN EAR PROTECTING DEVICE Filed Aug. l, 1952 :equalized to prevent pain and injury thereto.

United States Patent VThe present invention relates to an ear protecting :device and in particular to a novel device for protecting the eardrum and other inner ear parts against pain or injury caused by noises, concussion, shocks and sensible changes in the barometric pressure.

The human eardrum is located in the middle ear and rersponds to fluctuations in air pressure and sound waves Jthrough the auditory canal. by the Eustachian tube to the oral cavity so that pressures The middle ear is connected von the opposite sides of the drum head are normally The .-Eustachian tube is a normally closed slit which opens in the act of swallowing or yawning from the action of lthe muscles lifting the palate. This tube is readily sub- ;ject to inammation arising from colds, sinusitis and other disorders of the oral and nasal passages. Consequently, during these times of inilammation its function is impaired, and sound waves and the like impinging against the drum head will be more sharply felt, sometimes resulting in severe pain and injury.

Furthermore, a perfectly healthy person is liable to injury of his eardrums from noises of excessive type, explosions, concussions, etc, and experience has shown that it is not unusual for military personnel to suffer punctured eardrums as a result of artillery fire and explosion. ln fact it is quite customary for these men to have impaired hearing for a short time after coming out of an area wherein there has been a large amount of gunre, explosions and the like, such as a battle area or the artillery and rifle range.

It is also a known fact that air waves above the normal audible range, which varies according to the individual but generally extends between 50 and 15,000 C. P. S., are apt to canse very severe pain and permanent damage to a persons ear. These waves, because they are not audible, are exceedingly dangerous and one is not aware of their existence until a painful sensation is detected, at which time the damage more likely than not has been done.

A number of devices to prevent injury to the ear or to mufile sound have been proposed. Most, if not all, of these prior art devices have been unsuccessful for a variety of reasons. Many of them are cosmetically unattractive and people are reluctant to wear them. rhis is particularly true of that type of ear protector which either covers the whole ear or projects outwardly from the ear.

Many of the prior art devices are of the type which project a substantial distance into the auditory canal. Frequently the Success of such device depends upon the tightness with which it plugs the auditory canal. If it is suiciently loose to be comfortable, the normal jaw action accompanying mastication, yawning, or even conversation will be enough to cause the plug to pop out of position. Furthermore, if the t is so Snug that it resists the popping out tendency, it is apt to cause serious injury to the auditory canal and develop an infectious condirice tion spreading vto the eardrum and thus defeat its own purpose.

Some of the prior art devices include solid ber material, such as cotton, wool, silk, and synthetic fibers, as a sound insulating means. At times these bers have been impregnated with parain or the like. Tests have conclusively demonstrated that such bers are inadequate in mui'lling sound waves and at high frequencies-4000 C. P. S. to 8000 C. P. S.show very little suppression characteristics.

Experiments have conclusively shown that it is not essential that the ear protector be inserted into the auditory canal but merely that it close and provide an adequate block at the outer end of the auditory canal. Furthermore, experiments have also shown that, when the ear protector is made in a large part of a cellular fibrous material, an extremely effective block of high frequency sound waves and air waves beyond the audible range is obtained, while also permitting muled but adequately audible transmission of sound waves within the conversational range lying between '500 and 2000 C. P. S.

It is the principal object of the present invention to provide a device for preventing pain and injury to the ear, particularly the eardrum, arising from noises, concussions, shocks, explosions and excessive and sensible changes in the barometric pressure at opposite sides of the drumhead.

It is another object to provide a novel ear protecting device adapted to be held in air wave blocking position at the outer end of the auditory canal with perfect cornfort Aand cosmetic attractiveness.

Another object is to provide a novel ear protecting device which will substantially block and mule sound waves of high frequency and air waves of a frequency higher than the audible range so as to prevent pain and injury to the ear, and which also will permit sounds in the conversational range to reach the eardrum.

A further object is to provide a novel ear protecting device which may be worn with perfect comfort and which will also stay in place during those movements of the jaw required by mastication and yawning and which will not be dislodged by a violent movement of the body or the head or a blow on the ear.

Another object is to provide a novel ear protecting device which is readily put in sound-blocking position at the outer end of the auditory canal and removed from that position.

Another object is to provide a novel ear protecting device in which a quantity of fine air cell providing material is held in sound and air wave blocking position at the outer end of the auditory canal.

Still another object is to provide a novel ear protecting device attaining all of the foregoing objectives and which is economical to manufacture, easily packaged, and may readily be carried in ones pocket or purse.

Other objects and advantages will become apparent from the following description taken in conjunction with the accomapnying drawing, wherein:

Fig. l is a fragmentary view of a human head and ear showing the novel ear protecting device of this invention in sound and air wave blocking position at the outer end of the auditory canal;

Fig. 2 is a view similar to Fig. l but illustrating the manner in which the ear protecting device is manipulated to place it in position or to remove it;

Fig. 3 is a sectional View through the auditory canal and illustrates the manner in which the ear protecting device of this invention closes the outer end of the canal;

Fig. 4 is a longitudinal cross sectional view of a preferred form of ear protecting device constllld. according to this invention;

' 3 Fig. 5 is a view'similar to Fig. 4 but illustrating a modified form ofear protecting-device; and

Fig. 6 is an end viewof ythe device and may be considered asbeing taken from the right end of Fig; 4.

Dur-ing the following description referencewill be had to different portions of the human ear, andthe-following table designates the reference characters for the different parts of theear: Y

A-helinr B-.antihelix C-fossa of the antihelix D.-antitragus E-tragus F-concha G-.auditory canal VReferring firstV to the principal modification, and in particular to Fig. 4, the ear protecting device is indicated as a Whole by the reference lcharacter it) and comprises a Vcentral tubular part 1-2 terminating at one endin a hall like or bulbular casing i4. its opposite end 16 is'closed by a removable plug 1S. The tubular part 12 and bulbular casing M are preferably made of a very high quality rubber or latex, and it has been found that t e Wall of the tube might properly be about 2?/647 or 1/16/ thick, and the outside diameter be not greater than M1". If the tubular portion be about 1% long,.a satisfactory length is provided forthe device l0 sothat it might fit the average human ear. The diameter of the bulbular casing Mis ,between 1/2 and 5/8" with a wall thickness about 1,54" so that the casing is sufciently pliable comfortably to fit the Wearers ear and effectively to conform itself to the outer end of the auditory canal.

The casing 3A is filled with an air cell providing Vmaterial 20v/bieb is inserted through the tube i2 in a suitableV manner such as by dilating Vthe tube and holding it in dilated position until the casing i4 has been filled. The cellular material'Ztlpreferably may consist of milk- Weed oss fibers, kapokiibers or cellular glass fiber. Ex-

perience has shown that milky/eed floss -fiber is preferred over other known cellular fibers because of its deterioration resisting characteristics, its casein handling, and its somewhat lighter weight. Miikweed floss in its natural stateV is an extremely fine tube having a length of 3A" to l1/2" and in its separated form is closed at one end and open .at the other endto form a minute dead air space or cell. Milkweed oss fiber, or other air cell providing Vfibers filling the casing, provideV Within their fiber structure a very great multiplicity of extremely small air cells, and another multiplicity of small air spaces or traps is provided among these fibers. vSound blocking characteristics of the cellular fibrous material in the casing 14 arise from the combinationrof Vtherclead air spaces in the fibers and the minute traps ofthe encased fibers. K

It has been foundas a matter of fact, that the casing i4, filled Vwith cellular material such as milkweed oss and placedV insound blocking position over the'outer end of the auditorycanal, blocks sound and air waves from entry because the casing i4 is pliable and will conform itself to the ear contour. It has been found that, VWith the canal so sealed, sounds or speech within the conversation range Vbetween v500 and 2060 C. P. `Sfare transmitted to theeardrum in sufficient intensity as to permit conversation. It is true, however, that these sounds will be somewhat muflied but not so as to prevent conversation.V it has also been found that sounds in the frequency range and air Waves of frequency above the audible range are very substantially muffled so that extremelysharp sounds, such as explosions, are not transmitted to the eardrum with an intensity sufficient to darnage the eardrum or cause injury to the wearer. Furthermore, the ear'protector affords Vprotection against Ythose high frequency air waves (above the audible range) which, because of their siience, are extremely insidious 4 n in ltheir nature and even more harmful than high Vfrequency sound.

Experiments conducted with an ear protecting devic constructed in accordance with the teachings of this in-V vention and using milkweed oss as the sound insulating material and a prior art protector incorporating cotton fibers which were subjected to comparative tests con'- clusively show that the device of this invention suppresses sound in the high frequency range by as much as 35 decibels While the prior ait device had suppression characteristics in the same frequency range of not more than l5 decibels. Y j Y The principles which apply to sound andair .Waves in connection with injury to the ear and the utility of the device 'of this ivention in protecting. against that iniury likewise pertain to sensible changes in the barometn'c pressure. Therefore, the ear protectorof this invention guards against discomfort and ear injury arising from changes in barometric pressure such-for example as those encountered in air flight and ascendingor-.descending.sevf eral thousand feet in an aircraft of the Vnonpressurized type.

The plug 18, Whichcloses the end 15 of the tube 12, comprises a .cylindrical part 22 which is inserted into the tube 172 and a cap part 24 which'has an underside 26 bearingagainst the outer end of the tube 12. The

cap 24 has the shape generally seen in Fig. 6 and itsY dimension is greater in one direction than in the other being provided Withsubstantially attraight sides 28. rl`heplug 18 is preferably made of rubber or a rubber.- like material, and the outer surface 290i thecap por.- tion 26 is curved and is pliable so that it might conform itself to the shape of the concha F whereby the ear protecting device i@ is` comfortably held in place. 1

The ear protecting device 10 is put into the sound blocking position in the ear by placing the casing 14 at the outer end of the auditory canal G and behind the tragus E. In order to then engage the cap or pad 2.4 in the concha F it is necessary to bend the tube portion i2 slightly outwardlytopermit the cap or-pad 24'tobe inserted under the cartilage defining the concha F. The device is maintained in sound Vand airvvaveblocking p0- sition by virtue of the resiliency of the `tubularportitm 12 and the ability ofthe cap or pad 24 to conform itseif to the shape of theV concha. Because the casing 14 is extremely thin and very pliable, and becauseV the cellular fibers 20 respond to the deformation of the casing i4, the outer end of the auditory canal G is effectively blocked by conformation of the casingto `the ear configuration at the outer end of the canal. The device is removed in the same way as it was inserted, namely, by 'bending the tubular portion i2 .outwardly and then removing the bulbular casing 14 fromthe outer'end of the `canal Gand behind the tragus-E.

It is observed from AFigi that the device 10 occupies a very inconspicuous position in therear, and ifthe tubular portion 12, casing 14 and cap 24 arertinted with a flesh color it will be substantially indetectable totheV vcasual observer.

in the modified form shown in Fig. 5*, a tube 3f), having the length, diameter and Wall thickness generally culled for for the tubular portion 12, isprovided. One end of the tube is closed by a cap or pad 32 having a plug portion 34 inserted into the `tube and a hollow cap portion 36 with a curved concha engaging face 57. lBecause the cap portion 36 is hollow, it will shape itself Vinto the concha F extremely readily. The opposite end of the tube 3i) receives a sack 33 formed of cloth, preferably batiste, although other suitable cloth material having sterile characteristics may be used. The sack 38 is filled with cellular material-such Yas milkweed floss fibers, kapok fibers and cellular glass fibers-and its open end is gathered together as at et! .and inserted into the tube 3f).k Theear protecting device as shownin Fig. 5 is inserted into theear and held in place in the same manner as that shown in Fig. 4 and operates in substantially the same manner.

While preferred embodiments of the protecting device constituting this invention have been shown and described, it will be apparent that numerous further modifications and variations thereof may be made without departing from the underlying principles of the invention. lt is, therefore, desired by the following claims to include within the scope of the invention all such variations and modifications by which substantially the results of this invention may be obtained through the use of substantially' the same or equivalent means.

What is claimed as new and desired to be secured by United States Letters Patent is:

l. An ear protecting device of the class described comrising a quantity of air cell providing sound insulating fibers consisting of milkweed floss liber, and means confining said fibers so as -to lbe held in air wave blocking position at the outer end of the auditory canal.

2. An ear protecting device of the class described comprising means forming a pliable sack, a quantity of air cell providing sound insulating fibers consisting of milka/voed iioss fiber filling said sack, said fibers having the characteristics of substantially blocking sound and air Waves of high frequency while permitting muffled transmission of such waves in the conversational frequency range, and means connected to said sack for removably securing said sack in air Wave blocking position at the outer end of the auditory canal.

3. An ear protecting device of the class described comprising a pliable casing, a quantity of air cell providing sound insulating fibers filling said casing and having the characteristics of substantially blocking sound and air Waves of high frequency while permit-ting muffled transmission of such waves in the conversational frequency range, and resilient means including a tube having an end connected to said casing and another end adapted to engage an external part of the human ear lfor removably holding said fiber filled casing in air wave blocking position at the outer end of the auditory canal.

4. An ear protecting device of the class described comprising a pliable casing, a quantity of air cell providing sound insulating fibers filling said casing and having the characteristics of substantially blocking sound and air Waves of high frequency While permitting muffled transmission of such Waves in the conversational frequency range, a bendable tube connected at one end to said casing, and a soft cap closing the other end of said tube and adapted comfortably to engage the concha of a human ear, whereby the device may be removably held in place with said `fiber filled casing in sound blocking position at the outer end of the auditory canal.

5. An ear protecting device of the class described com- Y prising a deformable bulbular casing formed of a thin rubber-like material, a quantity of air cell providing sound insulating fibers filling said casing and having the characteristics of substantially blocking sound and air waves of high frequency while permitting mued transmission of such waves inthe conversational frequency range, a bendable tube having one end integral with said casing, said tube having a wall thickness such that said tube returns to its original shape after being released from a bending force, and soft cap means closing that end of said tube opposite said casing and adapted comfortably to engage the concha of a human ear whereby the device may be removably held in place with said fiber filled casing in sound blocking position at the outer end of the auditory canal.

6. An ear protecting device of the class described comprising a deformable casing formed of a cloth-like material, a quantity of air cell providing sound insulating bers lling said casing and having the characteristics of substantially blocking sound and air waves of high frequency while permitting muffled transmission of such waves in the conversational frequency range, a bendable tube to one end of which said casing is secured, said tube having a wall thickness such that said tube returns to its original shape after being released from a bending force, and a soft cap means closing that end of said tube opposite said casing and adapted comfortably to engage the concha of a human ear whereby the device may be removably held in place with said fiber filled casing in sound blocking position at Athe outer end of the auditory canal.

7. An ear protecting device of the class described comprising a deformable thin-walled casing, a quantity of air cell providing sound insulating fibers filling said casing and having the characteristics of substantially blocking sound and air waves of h-igh frequency While permitting muffled transmission of suc-h Waves in the conversational frequency range, a pad means adapted to engage against an externa-l part of the human ear, and a resilient memoer interconnecting said casing and said pad means so tha-t the device may be removably held in place with said fiber filled casing in sound blocking position at the outer end of the auditory canal.

8. An ear protecting device of the class described comprising a deformable :thin-Walled casing, a quantity of air cel-l providing sound insulating fibers filling said casing and having the characteristics of substantially blocking sound and air waves of high frequency while permitting muilied transmission of such Waves in the conversational frequency range, and resilient means connected to said casing and including a soft pad part adapted to engage an external part of the ear for removably holding sa-id fiber filled casing in sound blocking position at the outer end of the auditory canal.

References Cited in the file of this patent UNITED STATES PATENTS 706,975 Macbeth' Aug. 12, 1902 2,441,866 Cantor May 18, 1948 FOREIGN PATENTS 977,197 France Nov. 8, 1950

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