Communications headset

Abstract: A lightweight, monaural communications headset is disclosed which is readily adjustable to be worn on either the right or left ear of a wearer. The disclosed headset consists of two housings, one (12) for holding electronic circuitry (26) for the headset, and the other (14) for holding an acoustical receiver (46). The two housings are coupled with a swivel or ball-and-socket coupling (34), so that the device may be positioned behind either the right or left ear of a wearer. The receiver housing (14) is provided with acoustical port holes (32) on both of its sides to further facilitate the reversible wearing of the device. The disclosed headset is constructed from lightweight materials so that it is self-supporting, and causes minimal discomfort to the wearer.

Description: This invention relates generally to communications headsets, and more particularly to self-supporting, monaural headsets containing a microphone and a receiver. Communications headsets can be used in a diversity of applications, and are particularly effective for telephone operators, radio operators, aircraft personnel, and for other situations wherein it is desirable to support "hands free" access to communications systems. Accordingly, a wide variety of headsets have been known in the prior art. Known communications headsets can be broadly characterized on the basis of several fundamental aspects of their design and function, including: whether they deliver monaural or binaural sound; whether they are right-handed, left-handed or neither; whether they employ an invasive ear tip or a non-invasive loudspeaker in establishing a receiver-to-ear acoustical coupling; how they are physically supported on the user; their acoustical characteristics; and their economic qualities. Typically in the art, headsets which deliver binaural sound (i.e. ones which have acoustical transducers for both ears) may be neither right-handed nor left-handed, and may utilize some type of headband arrangement to secure receiver elements beside each ear. Although generally providing very stable support for the headset, headbands have the disadvantages that they increase the size and weight of the headset, and tend to be uncomfortable or obtrusive to the user. Monaural headsets (having only a single receiver situated near one ear) may be quite compact, and therefore may not require the high stability of a headband. Uneven weight distribution can be a problem for monaural headsets, however, since the majority of the headset components are concentrated on one side of the head. Known self-supporting monaural headsets often rely on a molded ear tip inserted into the entrance of the auditory meatus for securing the device to the user. Such invasive eartips, like the one for instance known from document US-A-3 548 118 which has been used to delimit the preamble of claim 1, have the disadvantages of being uncomfortable and unhygenic. In addition, invasive eartips must conform closely to the geometry of a user's ear in order to be stable and secure, and are therefore typically either right-handed or left-handed only, and may not be optimally effective on all users. Ergonomic considerations in the design of communications headsets include the comfort of the device, the ease of putting the headset on and subsequently adjusting it for use, the restriction of user mobility resulting from the wearing of the headset, as well as the quality of sound delivered by the device. Acoustical qualities of communications headsets are often closely dependent on other aspects of the design. For example, the acoustical quality of the sound heard by a user is clearly affected by the nature of the receiver-to-ear seal. Invasive ear tips provide a good seal, but suffer from the aforementioned problems of comfort and hygiene. Non-invasive loudspeaker-type receivers, on the other hand, are more susceptible to acoustical degradation from background-level sound and attenuation of the acoustical wave passing through open space from the receiver to the auditory meatus. Another acoustical problem results from the arrangement and size of components in a headset. Naturally, it is desirable to utilize microphones and receivers of the smallest possible size and least weight, making the resulting headset as light and compact as possible. Typically, however, smaller components deliver a weaker acoustical signal, and must accordingly be closely coupled to the user. In addition, care must be taken, especially with miniaturized components in close proximity to each other, that the receiver(s), and transmitter of a headset be mechanically and acoustically decoupled. Lastly, the use of acoustic tubes within a headset to carry sound from its source to a transmitter or from a receiver to a user's auditory canal can subject the acoustical signals to undesirable resonance effects and other forms of interference, thus decreasing the overall frequency response and sound quality of the headset. It is a general object of the present invention to provide a lightweight, self-supporting headset which can be comfortably and securely fitted to a wide range of users without undue individual attention. It is a further object of the present invention to provide a headset which is shaped and constructed to be worn comfortably and stably behind the ear of a wearer. It is still another object of the present invention that a satisfactory receiver-to-ear coupling is established with a wearer's left or right ear with equal ease, and without the use of an invasive ear tip. In general, the foregoing and other objectives are achieved, in accordance with the present invention by the features of claim 1. Further embodiments are defined in the dependent claims 2 to 4. The novel features believed characteristic of a headset of the present invention are set forth in the appended claims. The invention itself, however, as well as other features and advantages thereof, will be best understood by reference to a detailed description of a specific embodiment which follows, when read in conjunction with the accompanying drawings, wherein: Figure 1 is an illustration of a headset in accordance with one embodiment of the present invention; Figure 2 is an illustration of one housing of the headset of Figure 1 depicting its contoured shape; Figure 3 is an enlarged illustration of both housings of the headset of Figure 1; and Figures 4a, 4b, and 4c are illustrations of a ball-and-socket joint coupling the housings of Figures 1 and 3; Figures 5a and 5b are illustrations of the headset of Figure 1 being worn on a user's right ear; and Figures 6a, 6b and 6c are illustrations showing the adjustment capabilities of the headset of Figure 1. Referring to Figure 1, a headset in accordance with one embodiment of the present invention is illustrated, designated generally as 10. Headset 10 comprises a first molded housing 12, a second molded receiver housing 14 coupled to first molded housing 12 in a manner hereinafter described, a telescoping voice pick-up tube 16 originating generally near the top of first molded housing 12, and an electrical cable 18 originating generally near the bottom of first molded housing 12. Voice pick-up tube 16 includes telescoping portions 16a and 16b allowing tube 16 to be extended or retracted such that the distal end 16c of pick-up tube 16 may be positioned adjacent to a wearer's mouth. Tube portion 16a is preferably made of a plastic, or another suitably flexible and lightweight material, while tube portion 16b is made of stainless steel or another suitably rigid material for facilitating a sufficiently tight frictional seal with a flanged end 16d of flexible tube 16a. Rigid tube 16b is detachably coupled to housing 12 by means of a ferrule 20. In particular, tube 16b is secured to housing 12 through slots in the sides of ferrule 20 which releasably engage a pair of pins 22 mounted in and extending radially from a cylindrical protrusion 21 of housing 12. Pins 22 are more clearly shown in Figure 2. Ferrule 20 is of a conventional structure well known in the art to allow for angular adjustment of pick-up tube 16. Housing 12 may comprise two mating parts which are affixed to one another as, for example, by pins, sonic bonding, or the like. When assembled, housing 12 is contoured to fit snugly but comfortably behind the ear of a user. Referring to Figure 2, a contour diagram of housing 12 is shown. Contour line C1 indicates the region of housing 12 having a thickness of approximately 10.16 mm (0.4 inches); contour line C2 indicates the region of housing 12 having a thickness of approximately 9.144 mm (0.36 inches). Housing 12 has a thickness of about 8.128 mm (0.32 inches) at contour line C3, 7.112 mm (0.28 inches) at line C4, and 6.604 mm (0.26 inches) at line C5. At lines C6 and C7, housing 12 has a thickness of approximately 6.096 mm (0.24 inches), at line C8 a thickness of approximately 5.080 mm (0.2 inches), and at line C9 a thickness of approximately 4.064 mm (0.16 inches). It should be noted that the contour lines C1 through C9 of Figure 2 are meant to indicate only generally the thickness of housing 12, and not to indicate boundaries of transition between one thickness and another; housing 12 is smoothly formed from molded ABS or the like, as previously described, and its surfaces are generally devoid of sharp or highly angular edges which could cause discomfort to a wearer. Referring now to Figure 3, a greatly enlarged view of housings 12 and 14 is shown with one side of each housing 12, 14 removed to expose internal elements. The contents of housing 12 include a microphone transducer 24 and a printed circuit board 26. Microphone 24 is acoustically coupled to rigid portion 16b of voice tube 16 via connecting tube 28, which meets an end of rigid voice tube 16b within ferrule 20. The coupling of connecting tube 28 with rigid voice tube 16b occurs generally within ferrule 20. As previously noted, ferrule 20 releasably engages housing 12 by means of pins 22. Connecting tube 28, microphone 24, and printed circuit board 26 are each supported within housing 12 by means of appropriately formed support struts 30, which struts 30 are preferably integral internal features that may be formed during the molding process of housing 12. With continued reference to Figure 3, receiver housing 14 contains a loudspeaker-type receiver transducer 46. Housing 14, like housing 12, is preferably constructed from two mating halves; in order to expose internal components of the receiver, one half of housing 14 is not shown in Figure 3. As indicated in Figure 1, each half of housing 14 provided with acoustical port holes 32 on its substantially planar face, for allowing sound produced by receiver transducer 46 to exit receiver housing 14 and be audible to a person wearing headset 10 on either the right or left ear. Receiver housing 14 is coupled to housing 12 by means of a joint designated generally as 34, adapted to allow for adjustment of receiver housing 14 with respect to housing 12. This joint is a ball-and-socket joint 34. An enlarged view of ball-and-socket joint 34 is shown in figure 4a. Tubular mounting beam 36 is rigidly supported within housing 12 by support struts 30. A circular collar 35 around a portion of beam 36 in housing 12 is received between supports 30, functioning to increase the stability of joint 34. Although tubular beam 36 is free to rotate in place within housing 12, collar 35 can serve to increase the frictional resistance to this rotation, so that the headset tends to remain in its adjusted position during use. A cap 37 is dispose on the end of beam 36 in housing 12 to prevent beam 36 from sliding axially out of housing 12. As an alternative to cap 37, beam 36 may be provided with a flared end to achieve the same result. With continued reference to Figure 4a, beam 36 enters housing 14 via a hole 40 therein. The inner diameter of hole 40 is larger than the outer diameter of tubular mounting beam 36, creating gaps 39 between housing 14 and beam 36. Formed around the end of beam 36 in housing 14 is a ball 38 which is frictionally supported within a cavity 41. As shown in Figure 4b, ball-and-socket joint 34 allows for angular and rotary motion of housing 14 in all directions with respect to tubular beam 36. This motion is limited, however, by the size of gaps 39 between beam 36 and housing 14. In Figure 4b, beam 36 is shown in two extreme positions, with the total allowable angle of adjustment (in the X-Y plane of Figure 4b) being designated by . Tubular beam 36, collar 35, ball 38 and cap 37 are shown in greater detail in Figure 4c. Referring again to Figure 3, receiver wires 42 enter housing 12 through ball-and-socket joint 34 and tubular beam 36, as previously described. Receiver wires 42 travel generally adjacent to connecting tube 28, continuing past microphone 24 and printed circuit board 26, where the wires 42 are combined with other wires originating on printed circuit board 26 to form the electrical cable 18. Support struts 30 generally define a path for receiver wires 42, so that the wires 42 do not interfere with other components within housing 12. Electrical cable 18 is secured to housing 12 by means of a resilient strain relief collar 44, which frictionally prevents cable 18 from being forcibly withdrawn from housing 12. Due to the symmetrical design of housings 12 and 14, headset 10 of the present invention is equally suitable for wearing on either the right or left ear. This capability is further facilitated by the provision of acoustical port holes 32 on both substantially planar faces of receiver housing 14, as well as by the ball-and-socket joint 34 coupling housing 12 to housing 14 and allowing for the adjustment of receiver housing 12 to lie adjacent to either a right or left ear. In Figure 5a, an illustration of a headset in accordance with the present invention being worn on the right ear of a wearer is shown. A portion of housing 12 is hidden from view in Figure 5, behind the auricle 50 of the wearer's ear, as indicated by the dashed line 52. The forwardly-directed portion of housing 12 including cylindrical protrusion 21 extends slightly in front of the ears not covered by auricle 50. With housing 12 in this position, cylindrical protrusion 21 is directed forward and down, generally in the direction of the wearer's mouth. Receiver housing 14 rests in front of the external acoustic meatus of the ear, coupled to housing 12 by means of ball-and-socket joint 34. Such a joint is preferred due to the increased freedom of adjustment which it affords. In Figure 5b, line 66 is tangent to housing 14 at the arbitrarily chosen point 68, and is fixed with respect to housing 14. Line 70 indicates the direction in which tubular mounting beam 36 extends from housing 12, along the central plane of housing 12. Line 71, which also lies in the central plane of housing 12, is perpendicular to line 70. Since line 66 is fixed with respect to housing 14, and line 70 (the axis of tubular mounting beam 36) is fixed with respect to housing 12, the angle between lines 66 and 70 is representative of the relative positions of housings 12 and 14, in the two-dimensional plane defined by the central plane of housing 12. Ball-and-socket joint 34 permits housing 14 to be moved in several directions with respect to housing 12. In particular, the circular movement indicated by arrows 72 and 73 allows receiver housing 14 to be moved generally forward and down (arrow 72) or aft and up (arrow 73) with respect to the wearer's head. This facilitates adaptation of housing 14 to the varying heights and widths of different wearers' ears. Furthermore, ball-and-socket joint 34 permits housing 12 to be rotated about the axis defined by by tubular mounting beam 36 in joint 34 (the axis designated as 70), as indicated by arrows 74; this permits receiver housing 14 to be folded into a position in which it rests lightly against the outer surfaces of the wearer's auricle. Lastly, ball-and-socket joint 34 permits rotation of housing 14 about line 71, as indicated by arrows 76; again, this permits comfortable use by different wearers having various auricular geometries. In accordance with a further aspect of this embodiment of the invention, the shape of the forwardly-directed portion of housing 12 and positioning of cylindrical protrusion 21 functions to restrict the range of movement of housing 14. Recall from Figure 3 that receiver wires 42 pass through tubular mounting beam 36 from housing 12 to housing 14, to be received by receiver transducer 46. Cylindrical protrusion 21 limits the rotational motion of housing 14 indicated by arrows 74 in Figure 5b to less than 360°. This limitation is crucial, since it prevents receiver wires 42 from being subjected to excessive stress and repeated over-twisting, possibly leading to wire fatigue or loosened electrical connections. The limited rotation of housing 14 around axis 70 is more clearly illustrated in Figure 6a, in which housing 14 and cylidrical protrusion 21 are shown from a line of sight along the axis 70 of cylindrical beam 36. In Figure 6a, housing 14 is shown in two positions corresponding to the extreme points of rotation about axis 70. Clearly, the arc of rotation designated by the line 78 is less than 360°. Figures 6b and 6c are similar axial views of housings 12 and 14 showing the typical relative positions of these housings while headset 10 is being worn on the right and left ears, respectively, of a wearer. In Figure 6b, acoustical signals produced by receiver 46 in housing 14 travel in the direction indicated by arrow 80 to be heard by the wearer; in Figure 6c, sound heard by the wearer travels in the direction shown by arrow 82. Since the rotation of housing 14 about axis 70 is limited to less than a complete rotation, it is necessary for acoustical signals to be emitted from both planar faces of housing 14, in the directions indicated by arrows 80 and 82 in Figures 6b and 6c. Accordingly, and in keeping with the overall symmetry of housings 12 and 14, acoustical port holes 32, such as are shown in Figure 1, are provided on both sides of housing 14. Acoustical port holes 32 must be of sufficient size to allow sound to be emitted from housing 14 without undue acoustical degradation. From the above detailed description of a specific embodiment, it should be evident that a lightweight, monaural communications headset has been disclosed which is capable of being worn on either the right or left ear of a user. Although a specific embodiment has been disclosed in detail, it is to be understood that various changes, alterations and substitutions can be made therein without departing from the scope of the present invention as defined in the appended claims.

Claims: A communications headset comprising: a first housing (12) containing a microphone transducer (24) and electronic circuitry (26), the first housing (12) being symmetrical about its central plane and having a substantially hook-shaped outline in its central plane, such that the first housing (12) can be lowered into a secure, post-auricular position, an interior curve of said hook shape engaging the wearer's ear and securing said first housing (12) behind the auricle, around the rear and top of the ear, with a forwardly-directed portion of the first housing (12) extending partially in front of the ear; and a flexible, telescoping voice pick-up tube (16) having proximal (16b) and distal (16c) ends, the proximal end (16b) detachably coupled to a cylindrical protrusion (21) on the forwardly-directed portion of the first housing (12) and extending forward and down from the first housing (12) such that the distal end (16c) can be positioned generally in front of the wearer's mouth, characterized in that said communications headset further comprises a second housing (14), symmetrical about its central plane and having a substantially teardrop-shaped outline in its central plane, containing an acoustical receiver (46) having wires (42) coupled thereto, the second housing (14) having acoustical port holes (32) on both of its substantially planar and teardrop-shaped outer surfaces and being coupled near its apex to said forwardly-directed portion of the first housing (12) with a ball-and-socket joint (34) which allows limited angular and rotary movement of the second housing (14) with respect to the first housing (12) such that the second housing (14) may be folded inwardly to a position substantially parallel with the external surfaces of the wearer's ear, the ball-and-socket joint (34) also permitting rotation of the second housing (14) about the axis of the ball-and-socket joint (34). A communications headset in accordance with claim 1, characterized in that said cylindrical protrusion (21) extending from said forwardly-directed portion of the first housing (12) limits said rotation of the second housing (14) with respect to said first housing (12), preventing complete rotation of the second housing (14) about the axis of said ball-and-socket joint (34). A communications headset in accordance with claim 1 or claim 2, characterized in that said ball-and-socket joint (34) defines a hollow channel between the first (12) and second (14) housings through which said receiver wires (42) may pass. A communications headset in accordance with any of claims 1 to 3, characterized in that said microphone transducer (24) is electrically coupled to said electronic circuitry (26), for converting the wearer's speech into electrical signals and in that said flexible, telescoping voice pick-up tube (16) conducts acoustical signals produced by the wearer to said microphone transducer (24) for conversion to electrical signals.

Inventors: BERNARDI ROBERT J, SCOTT CHARLES G, BERNARDI, ROBERT J., SCOTT, CHARLES G.
Applicants: PLANTRONICS, PLANTRONICS INCORPORATED
Application year: 1990
Main classification: H04R1
IPC codes: H04M1, H04R1, H04R25