US 3368644 A
Description (OCR text may contain errors)
Feb. 13, 1968 J. D. HENDERSON 3,368,644
HEARING AlD TONE TUNING DEVICE AND METHOD Filed March 28, 1966 4v EH T02- JOHN D. fiewosefia/f ATTOIIZNEYE United States Patent This invention relates to a hearing aid tone tuning device and method.
The present application is a continuation-in-part of my application Ser. No. 497,132, filed Oct. 18, 1965, which is being abandoned upon the filing of the instant case.
The invention contemplates the infinitely variable tuning of a hearing aid sound tube or car plug by opening or closing communication passages in elastically deformable material by introducing or withdrawing relatively less elastic tubes. The elastically deformable element may be a part of an air plug or it may be at some other location between the transducer and the patients ear canal.
Conventionally, the device will be incorporated in the ear plug to provide for infinite variation by pushing the sound tube into the deformable material or withdrawing it therefrom. In some instances, I may use similarly a second tube to open and close a vent to the atmosphere. Because the infinitely variable tuning can be done with the hearing aid in use by the wearer, a very high degree of accuracy in optimum result is obtainable, the tone quality being tested continuously by the patient while the adjustment is in progress.
In the preferred operation, the sound tube and the ear vent or both pushed completely through the plug. The sound tube is connected to a speaker and is then gradually withdrawn, with the speaker in operation. In some position the desired effect is achieved and reported by the patient. The same practice is followed with regard to the vent tube until the quality of reproduction is at the desired peak. Both tubes are then left in the adjusted positions and the vent tube is cut off, leaving the sound tube as the only external projection from the plug.
A similar operation involving the sound tube only tunes the device when it serves as a coupling elsewhere, as in a coupling between transducer and sound tube.
In the drawings:
FIG. 1 is a view in side elevation diagrammatically illustrating an ear plug and a portion of the temple of an eyeglass hearing aid.
FIG. 2 is an enlarged detailview taken in section through the ear plug with the sound tube and air vent tube in their positions of initial insertion, portions of the sound tube and air vent tube being broken away.
FIG. 3 is a view similar to FIG. 2 showing the respective tubes in one adjusted position of use, any exterior portion of the vent tube having been cut off flush with the outside of the ear plug.
FIG. 4 is a view similar to FIG. 3 showing the tubes in a slightly different adjusted position and showing an arrangement in which the ear plug is relatively inelastic and the desired adjustment is made possible by using an elastically deformable element of spongy material housed within the plug.
FIG. 5 is a view showing a modified embodiment in which the deformable element has its passage opened and closed by bodily displacement of its sides as compared with the compression of the sides of the passage as in FIGS. 2 to 4.
'FIG. 6 is a view similar to FIG. 5 showing the bodily displaceable side wall of the deformable element opened up by the insertion of the sound tube to a point beyond that at which it is illustrated in FIG. 5.
FIG. 7 shows a further modified embodiment in which the elastically deformable element lacks the flanged terminal portion illustrated in FIGS. 5 and 6.
FIG. 8 is a further modification in which the deformable element is not located in the ear plug but is a coupling element disposed in proximity to the transducer outlet of a hearing air eyeglass temple.
The hearing aid selected to exemplify the invention contemplates transducers, amplifier and battery built into the temple 10 of a pair of eyeglasses, a conventional position of the speaker or transducer 12 being shown in dotted lines. Whether or not an eyeglass hearing aid is involved, a sound tube 16 leads from the transducer outlet 1-4 to an ear. plug 18 of any desired type, its external contour normally being fitted to the ear canal and the outer ear of the patient.
The portion 20 which projects into the ear canal is an elastomeric sponge which is resiliently deformable by compression or otherwise. It may conveniently be made of rubber or synthetic resin. It has a restricted sound passage 22 opening toward the patients ear canal. The predetermined normal cross section of this passage is very small, as indicated at the right in FIG. 2. It may also have a potential vent passage 24 which is not normally open at all. It is characterized as a potential passage because the continuity of the sponge material has been broken (as by forcing a needle through it). However, upon withdrawal of the tool used, the passage closes itself and is not reopened except as forced open in the manner hereinafter described.
The sound passage 22 may be expanded in cross sec tion by forcing an end portion of the sound tube 16 into it and progressively advancing the sound tube toward the end 26 which is within the patients ear canal. The opening 28 through the rigid or relatively inelastic portions of the ear insert 18 is large enough so that it will not offer any substantial resistance to the insertion of the sound tube 16. Only after the sound tube passes beyond the opening 28 and into the opening 22 of the sponge rubber extension 20 will there be resistance to the continued advance of the air tube toward end 26 of the insert. In the course of this advance, the length of the remaining unexpanded portion of passage 22 will be varied and this will affect the tuning. When the sound tube 16 is advanced to the point indicated in FIG. 3, the cross section of the remaining unoccupied part of the passage 22 will be expanded ahead of the sound tube as shown at 30 in FIG. 3. This also will alfect the tuning.
The sound tube can be pushed in and out while the hearing aid is in use and this permits a very fine adjustment because the change in tuning in infinite and the patient is able to designate during continued functioning of the hearing aid the precise point at which the tuning is most acceptable to him.
When the sound passage 22 has ben adjusted in length and cross section to the capacity which gives the best tone, the atmospheric vent passage 24 will be similarly adjusted by inserting into it a short length of tube 32 which is of small cross section. As shown in FIG. 2, the potential passage 24 is completely closed except in the immediate vicinity of the tube 32 which is being used for tuning. When the tube 32 reaches a position such as that shown in FIG. 3, the potential passage 24 has been opened as indicated at 24-0. Until such opening occurs, there is no communication through the potential passage between the ear canal and the atmosphere. Assuming that the patient feels that the opening of the atmospheric vent does not improve the results already achieved, the tube 32 may be completely withdrawn, leaving no opening whatever, or substantially none, through the potential passage 24, the elasticity of the sponge material at 20 being suflicient to close the passage again during withdrawal of the tube 32. If the tube 32 gives improved results in some predetermined position, for example, as that shown in FIG. 3, its external portion is preferably severed flush with the outer surfaces 38 of the ear plug 18.
Some persons prefer that all surfaces of the ear plug which contact the body be made of some relatively inelastic and easily cleanable material such as an acrylic resin. In such instances, results comparable to those described above can be achieved by counterboring the plug to provide a socket at 40 to receive a tube 42 of elastomeric sponge material having a potential passage of initially restricted cross section. Into this passage the sound tube 16 is inserted and manipulated as already described. The acrylic or other non-elastic plug 18 may similarly be provided with a bore at 44 for the tube 32 which tones the atmospheric air vent. In this instance, the potential (normally closed) air vent passage 24 will be formed in the inner end of the elastomeric sponge tube 42 where it will be expanded and contracted into open or closed positions by the insertion or withdrawal of the tuning tube 32. When a satisfactory position for the tuning tube is found, it will be cut off flush with the outer surface of the air plug as already described.
The sponge rubber materials mentioned are deformed by compression of their side walls in the expansion of the passages therethrough. FIGS. and 6 disclose a modified embodiment in which the relatively inelastic ear plug has a bore 40 such as that provided in FIG. 4 but the insert 420 is molded of elastically deformable tubing which is not of sponge material. The mold provides a constricted passage at 46 about which the side walls 48 of the tube 420 are formed inwardly away from the surfaces of bore 40. When the sound tube 16 is forced into the insert 420 to the point shown in FIG. 5, it begins to push the side walls 48 bodily in an outward direction thereby tensioning the elastomeric material and expanding the restricted passage 46 in a manner which differs from that above described only because the expansion results from bodily outward displacement rather than compression of the material.
In order to make the ear plug of more nearly universal application, the elastomeric insert 420 may be provided with a flange 50 at its inner end, the flange being of greater radius than adjacent portions of the plug so as to fill or substantially fill an ear canal which might have been too large to receive with tight fit the inner end of the ear plug proper. FIG. 6 shows the sound tube 16 advanced to a position in which the bodily displacement of the side wall portions 48 forming the restricted passage 46 have been so displaced that the passage has been materially enlarged in cross section as compared with its initial form illustrated in FIG. 5.
The elastomeric insert 420 need not be flanged. FIG. 7 fragmentarily illustrates an arrangement in which the elastically deformed tube 422 is only a little more than half the length of that shown in FIGS. 5 and 6, being terminated at the point where the sound passage 46 through the deformable side wall portions 48 is of minimum cross section. This construction is advantageous when, for some reason, it is desired that the ear plug 18 be shorter than those shown in the other views.
FIG. 8 shows an embodiment in which tuning is done elsewhere along the sound tube. The sound tube 16 enters the ear plug 18 in the usual manner. It will, of course, be understood that optionally there may be additional tuning if one of the ear plugs shown in the other views may be employed. However, the purpose of including FIG. 8 is to show a device in which an elastically deformable tube 424, comparable to that shown in FIGS. 5 and 6, serves as a coupling between the transducer outlet 14 and the sound tube 16, being elastically contracted upon the outlet 14 and having a constricted passage at 46 which is opened and closed by progressive insertion or progressive withdrawal of the inlet end of sound tube 16 exactly as if the tuning were being done in the assembly shown in FIGS. 5 and 6. If desired, the elastomeric tube 424 may be enclosed within a sleeve at 54 but this is an optional feature which is not essential to the invention.
Merely by way of example and not by way of limitation, it may be noted that the sound tube normally has an outside diameter of .125 inch and an inside diameter of .095 inch. The durometer values of the various elastomeric components will normally range between 20 and as desired. The materials used form no part of the invention; a wide variety of elastomeric and relatively nonresilient resins are well known to be available both in the form of sponge and in the form of bodily deformable materials.
1. In a hearing aid, a tuning device comprising an elastically deformable ear insert having a restricted passage through it, and a tubular liner of relatively less elastic material extending into said ear insert through at least a portion of the passage and adjustable in advance longitudinally thereof, the liner having an external cross section greater than the initial restricted cross section of the passage whereby progressively to expand the cross section of the passage as the liner is advanced therein.
2. A device according to claim 1 in which the tubular liner comprises a portion of a hearing aid sound tube.
3. A hearing aid according to claim 1 in which the deformable ear insert has had an atmospheric passage formed therein, which passage is normally closed by the elasticity of the deformable insert material, and a liner of relatively less elastic material is telescopically adjustable in said atmospheric passage in a range of movement in which the cross section of the normally closed passage is progressively opened and closed to a variable extent as the liner is advanced and retracted therein.
4. A device according to claim 1 in which said insert has about said passage elastically compressible walls of spongy material, the expansion of the passage consequent upon the insertion of the liner being effected by the compression of the walls of said insert.
5. A device according to claim 1 in which said insert comprises wall portions about said passage which are elastically deformable by bodily displacement, the expansion of said passage consequent upon the insertion of the liner involving a bodily displacement and circumferential tensioning of said last mentioned wall portions.
6. A method of tuning a hearing aid having a sound passage and which includes a sound tube and an elastically deformable ear insert having a passage providing an initially restricted portion, said method including the steps of: using the hearing aid with a sound tube of larger diameter than said passage; telescopically engaged in said insert to an extent suflicient to expand said passage at one end thereof, leaving the inner portion of the passage restricted, and infinitely varying the tuning during the use of said hearing aid by changing the form of said passage by advancing and retracting the sound tube into and from the restricted portion of said passage.
7. A method according to claim 6 in which said insert has an atmospheric passage formed therein and closed by the elasticity of the deformable insert material, said method including thefurther step of adjusting a vent tube in said closed atmospheric passage to an extent suffi-cient at least to effect partial opening thereof, whereby infinitely to vary the tuning resulting from change in form of the atmospheric passage While the patient is using the hearing aid.
References Cited UNITED STATES PATENTS Fiene 18123 Coley 18123 Wallace 179-407 Touson 18123 StrzalkOWski 18123 Henderson 18123 Victoreen 179-479 Kohler 18131 8/1930 French 181 23 10 TEPHEN J. TOMSKY, Primary Examiner.