Earpiece for Acoustic Headset

This invention relates to acoustic headsets, and more particularly to earpieces for such headsets.

Acoustic headsets having sound-transmitting tubes are fitted with earpieces designed to engage the wearer's outer ear. Such earpieces have a central hub that receives the acoustic tube, and a flange projecting symmetrically from the hub which is intended to seal against the outer ear in the region of the ear canal, and to become deformed as the wearer adjusts the center of the earpiece into position communicating effectively with the ear canal. While the purpose is well conceived, the result has been poor. Few users are able to adjust the central passage of the earpiece opposite the ear canal, because the flange, despite its supple quality, nevertheless resists placement of the earpiece to the desired sound-coupling position.

In the novel earpiece, the flange is at least weakened at places, by radiating slots or by webs or by slots at some places and webs elsewhere, so that extreme deformation of the flange at one region can occur without imposing needless distortion on the rest of the flange. Anyone who has embraced an egg with his fingers and tried to crush the seemingly frail eggshell has been impressed with the enormous resistance of the shell in relation to circular compressive forces that develop in the shell. The material of the shell is well suited to resist such stresses. The flange of an earpiece of conventional design is circularly symmetrical, and despite its soft material, it is a symmetrical figure of revolution of uniform thickness, and each region develops surprising resistance to deforming stresses developed when prominent deformation is imposed elsewhere. By using thinned regions, or sloping webs amounting to corrugations, or slots, or combinations of these, one region of the flange is encouraged to wrinkle or to shrink so as to allow the central passage of the earpiece to be moved opposite a wearer's ear canal and yet the remainder of the flange can stand out and become conformed reasonably to the wearer's outer ear, acting with reasonable effectiveness to exclude ambient sounds.

The illustrative embodiments of the invention described in detail below are shown in the accompanying drawings, wherein:

FIG. 1 is an enlarged rear view of a novel earpiece embodying features of the invention;

FIG. 2 is a cross-section of the novel earpiece viewed at the plane 2--2 in FIG. 1;

FIG. 3 is a fragmentary cross-section of the earpiece of FIG. 1 as viewed along the cylindrical surface 3--3 in FIG. 1;

FIG. 4 is an enlarged view of the earpiece of FIGS. 1-3 in position opposite a wearer's outer ear shown diagrammatically in phantom lines and including portions of the headset that bears the earpiece, such portions also being shown in phantom lines;

FIG. 5 is a fragmentary view of a portion of an earpiece distorted in the region of section line 5--5 in FIG. 4;

FIG. 5A is another view similar to FIG. 5, showing another flange portion of a distorted earpiece; and

FIG. 6 is a modified earpiece viewed in cross-section similar to FIG. 2.

The earpiece 10 includes a tubular hub 12 and a flange 14. A through axial passage 16 has a cylindrical portion ending with an annular abutment 18 for the end of a pliable acoustic tube T of a stereo headset carried by a light plastic frame F. Passage 16 extends from the reduced-diameter portion adjacent abutment 18 to a flared opening 19 formed by flange 14.

Flange 14 includes many relatively thick portions or ribs 20 (eight ribs in the form illustrated) extending outward from the tubular hub 12, in a generally conical configuration. When placed against a person's ear, the slight weight of the stereo headset forces the lower ribs to bend. Being spaced apart initially, the ribs move readily toward one another, allowing the earpiece to become aligned with the ear canal of the wearer, and then to support the headset. If the ribs were part of a soft wall of uniform thickness, this action could not occur. This is because, in the case of the uniform wall, the wall cannot be compressed in a circular direction (e.g. along line 3--3) to a comparable extent by such light forces, and required deformation of the flange in one region is resisted to a remarkable degree by the rest of the flange. In the case of earpieces that depend upon deformation of such a flange, it is difficult to find the right fit, such that the passage of the earpiece and the wearer's ear canal are aligned.

As shown, ribs 20 are divided and separated by notches 22 at some points. Webs 24 and 26 are provided for excluding ambient sound. Thin webs 24 extend from rib to rib. Such webs readily form folds when the ribs are bent, as represented by web 24' in FIGS. 4 and 5. Webs 26 may become overlapped as shown in FIG. 5A. While not readily apparent in the drawing, webs 24 extend well into the transition region 19 between flange 14 and tubular portion 12. By like token, thinned webs may extend inward radially from the inner ends of notches 22. Webs 24 do not lie along an imaginary conical outer surface of flange 14, nor do they lie along an inner imaginary conical surface of flange 14. (This statement applies correspondingly where flange 14 is not conical but some other shape, as a figure of revolution about a central axis.) As viewed in circular cross-section (FIG. 3, and see line 3--3 in FIG. 1), webs 24 slope or slant and thus promote the formation of folds such as folded web 24'. Furthermore, as shown in FIG. 3, webs 26 at the lateral edges of notches 22 are disposed in different "planes", or staggered or mutually offset, as shown in FIG. 3. This promotes the overlapped configuration of FIG. 5A whereas, were the webs 26 "coplanar" or aligned, they would tend to become abutting and so resist localized collapse of the flange in the circular direction when the wearer attempts to align through passage 16 with his or her ear canal.

A modification is shown in FIG. 6, including a tubular extension 30 of the hub 12' which, in FIGS. 1-5, ends at flange 14. The tubular extension at once complements the rest of the earpiece in sound transmission into the ear canal of the user and excluding ambient sound, and in assuring proper location of the passage through the earpiece opposite the ear canal. The rest of the earpiece of FIG. 6 is not described here. It is in all respects (except as already noted) the same as that of FIGS. 1-5.

The described and illustrated embodiments of the invention are evidently amendable to varied modification, and therefore the invention should be construed in accordance with its full spirit and scope.