US 2501107 A
Description (OCR text may contain errors)
March 21, 1950 Filed May 27, 1944 J. VOLKMANN 2,501,107
HEADBAND 2 Sheets-Sheet l March 21, 1950 J. VOLKMANN 2,501,107
HEADBAND Filed May 2'7, 1944 2 Sheets-Sheet 2 i .4 "Ma a-2:42
Patented Mar. 21, 1950 UNITED HEADBAND John Volkmann, Cambridge, Mass, assignor to the United States of America, as represented by the Secretary of War Application May 27, 1944, Serial No. 537,712
This invention relates to a headband for supporting earphones, and especially to earphones which are equipped with acoustic couplers for excluding ambient noise.
An acoustic coupler, usually consisting of a tubular member, is interposed between an earphone and the opening of an ear canal to shut out ambient noise and permit more efficient communication of signals transmitted through the earphone. It is essential that the acoustic coupler fit snugly in apposition to the opening of the ear canal to provide an orificial seal. A conventional headband in a slightly extended position about the head, is relied upon to provide a light pressure for urging the earphone and acoustic coupler against the ear and providing the required seal. However, if a helmet or other equipment comes into contact with the headband, pressure increases against tender ear cartilage portions and a great deal of discomfort may result. Conventional headbands are subject to the further disadvantage that they fail to provide for satisfactorily locating an acoustic coupler in apposition to the ear canal.
It is an object of the present invention therefore to improve headbands and to devise improved means for supporting earphones and acoustic couplers at the extremities of a headband, with a view to eliminating excessive pressure against ear cartilage portions and to providing for more satisfactorily locating acoustic couplers in apposition to ear canals. Another object is to provide improved adjustment means for a headband. The invention also aims to provide a simple, cheap and efiicient headband and earphone suspension device.
The nature of the invention and its objects will be more fully understood from the following description of the drawings and discussion relating thereto.
In the accompanying drawings:
Fig. 1 is a plan view of the headband of the invention;
Fig. 2 is an elevational view of the headband;
Fig. 3 is an enlarged detail view of one extremity of the headband with supporting means for an earphone and coupler attached thereto;
Fig. 4 is a plan cross section taken on the line 4-4 of Fig. 3;
Fig. 5 is a cross section taken on the line 55 of Fig. 4;
Fig. 6 is a cross section taken on the line 6--6 of Fig. 3;
Fig. 7 is an enlarged detail view of adjustment means for the headband;
Fig. 8 is an end elevational view of an acoustic coupler; and
Fig. 9 is a diagrammatic view illustrating an ear with an earphone and acoustic coupler supported in apposition thereto.
The invention in general includes a headband provided at its extremities with adjustment pieces. Secured to the free ends of the adjustment pieces are supporting members in which are pivotally mounted wire frames adapted to encircle earphones and engage around acoustic couplers attached to the earphones. The pivotally mounted frames are under spring tension and normally extend rearwardly and inwardly to assume an angular position with respect to the inter-aural axis. Such a position of the frames facilitates engagement of a coupler with an ear canal opening. The supporting members, frames and tension means combine to provide an isotonic spring arrangement which is adapted to equalize pressure on the cartilage portions surrounding the ear.
Referring more in detail to the drawings, Figs. 1 and 2 illustrate the headband of the invention with earphones and acoustic couplers supported in the position they normally assume when not in use. Numeral 2 refers to the headband of the invention at the ends of which are supported earphones 4 and ii. The earphones may be of any conventional type, and their construction forms no part of the present invention.
Numerals 8 and Ill denote acoustic couplers attached to the earphones. The couplers generally consist of tapered tubular members having communication channels adapted to connect with the earphones 4 and ii. At their inner ends the couplers are formed with sealing lips l2 and M, which are shaped to conform generally to those cartilage portions of an ear immediately surrounding the ear canal opening. The peculiar shape of an ear canal opening and the presence and arrangement of that part of the ear known as the tragus, make it necessary for the sealing lips to engage in back of the tragus. In order to become correctly located, therefore, the tubular couplers should be inserted while in an angular position so that they may easily pass in back of the tragus. The angular position of the earphones and couplers with respect to an axis passing between the ends of the headband, as illustrated in Figs. 1 and 2 of the drawings, is provided to facilitate location of the couplers.
Considering in detail the headband 2, it will be noted that this member is made up of a resilient metal band 16 which is bent into a bow, with an arc of curvature sufiiciently small so as to re- 3 quire that the ends be flexed away from one another when the band is assembled over the head of an operator.
At either end of the band l6 are located adjustment pieces I 1 and I 8 which are slidably engaged against the inner side of the band and surrounded by thin metal sleeves I9 and 28. The radius of the arc of curvature of the band I6, at points adjacent to the adjustment pieces I! and I8, is smaller than the radius of the arc of curvature of the adjustment members I! and I8, as may be more clearly observed from an inspection of Fig. 2. As a result of this, the adjustment pieces I! and I8 have their upper extremities resiliently urged against the inner side of band Hi. This provides a frictional contact which is adapted to maintain the adjustment pieces I! and I8 in a fixed position in the sleeves I9 and 28. However, a light pull is suificient to overcome the friction force and slide the adjustment pieces into any desired position, thus providing an efficient and convenient means of adjusting the size of the headband.
Numerals 2| and 22 refer to stops formed at the extremities of the adjustment pieces I! and I8, and these stops prevent withdrawal of the adjustment pieces from the sleeves I3 and 28. Surrounding the headband I6 and members I"! and I8 is a leather casing 23. This serves as a protective medium for keeping the bare metal out of contact with the head of the operator,
and also functions to eliminate interference with the act of sliding the adjustment straps upon the band.
Mounted at the free ends of the adjustment pieces I? and I8 are supporting members 25 and 26. The supporting members are of rectangular shape and are fixed to the ends of the adjustment pieces by means of rivets or some other desirable fastening means. Referring to Figs. 3, 4 and 5, it will be seen that each of the supporting members is constructed with sides 21 and 28, which are spaced apart to provide a box-like structure. The sides 21 and 28 may, for the sake of convenience, be considered as forming T-shaped portions, with the legs of the T-shaped portions extending rearwardly from the adjustment pieces at right angles to an axis passing through the ends of the headband; and the heads of the T-shaped portions lying in vertical planes. Between the sides 2 and 28 at those points corresponding to the heads of the T-shaped portions are bearing members 29, mounted one above another. Numeral 32 denotes a wire frame element which has its extremities bent over and pivotaily mounted through the bearings 29, as may be more clearly seen in Fig. 3. The frame member is of a rectangular shape, corresponding somewhat to the shape of the supporting member 28 and extends transversely between the sides 21 and 28 at the top and bottom of the T-shaped portions. (Fig. 3.) At those points where the frame member passes through the T- shaped portions, openings 33 and 36 are provided to form clearances which permit the frame member to swing through a limited arc of rotation. The opposite edges of the T-shaped portions, which define the openings 33 and 34, serve as stops for limiting the arc of rotation of the frame. They also function to prevent the support from being readily bent out of shape, should it be subjected to a sudden stress. (Fig. 5.) The frame member is of a width greater than the width of the leg of th T-shaped side. This permits the frame, in swinging through its arc of rotation, to avoid contact with the leg.
Surrounding the bent ends of the frame member 22 is a coiled spring 36, which has one end engaged against a side of the supporting member, and the opposite end attached to the frame member in a position such as that illustrated in Figs. 1 and 4 of the drawings. The frame member may be rotated outwardly against the tension of the spring through the limited arc of rotation above noted, to assume a position such as that illustrated in dotted lines at the righthand side of Fig. 1. The frame 32 is bent further into a position such that it extends rearwardly and inwardly, and terminates in a loop which passes around a groove 40 in the earphone 6, as may be more clearly observed in Fig. 3 of the drawings. In addition, the frame, at points adjacent to the loop, is reversely bent to pass over and in back of lug portions 44 which form a part of the acoustic coupler I8. The reverse bends of the frame prevents rotation of the acoustic coupler and insures the irregular surfaces of the sealing lips being located and held in proper relation to the cartilage portions surrounding an ear canal.
In Fig. 9 I have diagrammatically illustrated an ear 58, with an earphone and coupler located in apposition thereto by the supporting means of the invention. In operation, the headband is placed over the head of the operator and the adjustment pieces are moved into a position in. which the acoustic couplers roughly occur opposite the ear canal. Then the frame elements are pivoted outwardly to swing the couplers into a position such as that illustrated in dotted lines at the right-hand side of Fig. l. The frames are then gradually released and the couplers swing through a short are and come into engagement with the ear canal while in an angular position. This allows the couplers to readily pass in back of the tragus 5| and become seated in a sealed position whereby all portions of the ear cartilage surrounding the ear canal opening are contacted by the sealing lips.
After the coupler has been thus accurately located in apposition to the ear canal, the headband presses the supporting members gently against the side of the head, and the frames and spring tension means lightly press the couplers against the ears independently of the pressure exerted by the headband or any increase in pressure on the headband. It should be observed that this is especially important in connection With wearing a helmet or other covering which tends to exert pressure on the headband. The same eifect is true with respect to a sudden blow which may be directed against the headband or helmet.
It will also be observed that the support members terminate at points lying in a plane roughly tangential to the lowest peripheral surface of the earphone, and upon adjusting the headband, there are no projecting ends upon which connecting wires or other equipment may become entangled. The adjustment is taken care of by the adjustment pieces already described, with the engaged ends of the adjustment members being telescoped within the leather casing. The support members may also be covered with a leather casing which protects the face of the wearer and covers edges or corners upon which wire or other equipment may become entangled.
Numeral 54 denotes a snap fastener attached at the side of the support member. This fastener may be utilized to secure a lip microphone or other equipment, in front of the face. It is as: pointed out that the support member, in addition to its other functions, constitutes a convenient means of holding such snap fasteners.
It may be desired to provide other types of isotonic spring arrangements, secured at the ends of a headband. For example, I may employ levers, rods and other devices in place of the wire frame, and I may resort to other types of pivotal mountings to receive such devices. The isotonic spring arrangement may be utilized independently of the particular acoustic coupler illustrated in the drawings, and similarly, may be utilized with conventional headbands having no adjustment pieces. Also, the adjustment features may be employed independently of the isotonic spring arrangement.
While I have shown a preferred embodiment of my invention, it should be understood that various changes and modifications may be resorted to, in keeping with the spirit of the invention as defined by the appended claims.
1. An article of the character described comprising a headband, adjustable strap means slidably attached to the headband, bearing support members secured at the extremities of the adjustable straps, bearing members located in the bearing supports, frame members having their extremities pivotally mounted in the bearings, the axis of each of said pivotal mountings extending substantially parallel to the longitudinal axis of the adjacent adjustable strap means, and spring means for resiliently urging the frame members inwardly with respect to the said band,
said frame members adapted normally to support pivotally mounted in the bearing members, the 4 axis of each of said pivotal mountings extending substantially parallel to the longitudinal axis of the adjacent adjustment piece, and coiled springs surrounding the portions of the frame members in the bearings, each of said springs having one end engaging a supporting member and its other end attached to a frame member, said frame members having loop portions adapted to support ear hones.
3. In a headband, a resilient metal band member, adjustment pieces slidably engaging the inher sides of the ends of the band member, metal sleeves surrounding the ends of the band memher and adjustment pieces, stop lugs formed on the ends of the adj ustment pieces to prevent withdrawal of said adjustment pieces from the sleeves, the radius of arc of curvature of the band member at points adjacent the adjustment pieces being less than the radius of arc of curvature of the adjustment pieces, supporting members fixed to the ends of the adjustment pieces, said supporting members having spaced apart sides to form boxlike structures, bearing members positioned in the supporting members, wire frame members having their extremities bent over and pivotally mounted in the bearing members, and coiled springs surrounding the bent ends of the frame members having loop portions adapted to support earphones.
REFERENCES CITED The following references are of record in the file of this patent:
UNITED STATES PATENTS Number Name Date 820,463 Zimmerman May 15, 1906 1,398,958 Basch Dec. 6, 1921 2,075,196 Hand Mar. 30, 1937 2,337,953 Wirsching Dec. 28, 1943 2,353,070 Pitkin July 4, 1944 FOREIGN PATENTS Number Country Date 353,758 Germany May 24, 1922 237,514 Great Britain July 30, 1925