Abstract:
An ear-hanging type headphone has an ear hanger arm attached to a rotation shaft portion that is movably mounted on a convex housing of a headphone body at a location that is offset from a central axis of the convex housing by a predetermined eccentric angle. Upon moving the rotation shaft portion relative to the convex housing a distance between the ear hanger arm and a sound emitting side of the headphone is altered to facilitate placing the headphone on the ear. The rotation shaft portion can be spring biased toward one end position and a retaining element can be used to temporarily retain the rotation shaft portion at another end position.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an ear-hanging type headphone which does not require a headband, and more specifically, relates to a headphone wherein the ear hanger arm is rotatably constructed via a rotary shaft portion eccentric with respect to the central axis of the headphone body portion, to thereby improve the wearing property of the headphone. 
     2. Background of the Invention 
     Recently, with advancement of the times of individuation centering on the youth, demands for a product whose design is regarded as important are increasing even in the headphone industry. In a-case of an ear-hanging type headphone, there is a strong demand for one having fashionability for the outdoor use, not having an image regarding function as important, such as conventional ones used in indoors for guidance in museums or the like, or used in international conferences or the like. However, in the outdoor use, it is also important, in view of safety, that the headphone can be quickly removed and mounted, for example, when the user changes a train or the like. 
     Here, one example of a conventional ear-hanging type headphone is shown in FIG. 14. A speaker unit (not shown) is built in a headphone housing  30 , and one side of the headphone housing  30  is a sound production section side to which an ear cushion  31  is attached. An ear hanger arm  32  is connected by a fixed part  33  to the back side of the headphone housing  30 , bent to a shape wrapped around the ear, and arranged on the front side of the ear cushion  31 . The ear hanger arm  32  is made of a plastic molding material, and made detachable with respect to the ear cushion  31 , utilizing an elastic deformation force thereof. Reference symbol  34  denotes a code pulled out from the headphone housing  30 . 
     The above-described ear-hanging type headphone is mounted as shown in FIG. 15, in such a manner that the ear hanger arm  32  is hang on the ear with the ear hanger arm  32  being bent in a direction away from the ear cushion  31 , to thereby support the dead weight of the headphone by the ear hanger arm  32 , and the ear portion “e” is pressed on both sides of the ear hanger arm  32  and the ear cushion  31 . 
     FIG. 16 to FIG. 18 show another example of the conventional ear-hanging type headphone. This headphone is constructed such that the ear hanger arm  36  is rotatable about a supporting point  37  with respect to the headphone housing  35 , and located on the front side of the ear cushion  38 , and the ear hanger arm  36  is spring-energized toward the ear cushion  38  side by means of a spring member (not shown) provided in the supporting point  37 . 
     FIG. 19 to FIG. 21 also show an example in which the fitting angle of the supporting point  37  of the ear hanger arm  36  with respect to the headphone housing  35  is different from that of the headphone shown in the above-described FIG. 16 to FIG.  18 . 
     FIG. 22 also shows another example of the conventional ear-hanging type headphone. This headphone is constructed such that an annular ear-hanging section  39  in a longitudinally elliptic shape along the shape of the ear portion and a ring-shaped holding section  40  in which the headphone housing is held are integrally formed by a plastic molding material, and a headphone housing  41  having a built-in speaker unit is held in the holding section  40  with the sound production section being inside. The holding section  40  is protruded stepwise towards this side with respect to the annular ear-hanging section  39 , so that a gap “g” is produced vertically between the annular ear-hanging section  39  and the holding section  40 . 
     The ear-hanging type headphone constructed as described above is mounted in such a manner that the annular ear-hanging section  39  is supported by the ear portion by inserting the ear portion into the gap “g” in the direction of an arrow, to give the insertion fitted condition of the headphone. 
     The insertion fitting operation of the headphone shown in FIG. 14 has a problem in that insertion fitting of the headphone is troublesome, since it is insertion fitted such that the headphone housing  30  is held by one hand, and while widening the ear hanger arm  32  by the other hand so as to alienate it from the headphone housing  30 , the ear portion is inserted into the gap produced between them so as to be pressed on both sides. Moreover, the gap after completion of the headphone insertion fitting is required to be set narrow so as to give an initial load, taking into consideration the flexion of the ear hanger arm  32  due to the dead weight of the headphone. With such a structure, the gap is narrow on the side of the fixed part  33  of the ear hanger arm  32 , and the gap becomes large on the tip end side, and hence, the ear portion inserted on the fixed part  33  side is pressed and becomes sore. As a result, there is a problem in long time use. 
     The headphone shown in FIG. 16 can uniformly hold the ear portion only in a part where the ear hanger arm  36  is parallel to the headphone housing  35 , and as with the case of the headphone shown in FIG. 14, the gap is narrow on the supporting point  37  side of the ear hanger arm  36 , and the gap becomes large on the tip end side. Therefore, for example, when a headphone having a standard size L in the distance from the supporting point  37  to the bending portion of the ear hanger arm  36 , as shown in FIG. 17, is mounted on a large ear, the ear portion inserted on the supporting point  37  side is pressed and pain easily occurs. Moreover, when a headphone having a size L 1  for large ears in the distance from the supporting point  37  to the bending portion of the ear hanger arm  36 , as shown in FIG.  18 , is mounted on a small ear, a gap is formed between the headphone housing  35  and the supporting point  37 . As a result, there is a problem in that the headphone housing  35  does not come into intimate contact with the ear portion, causing sound leakage and decrease in the tone quality. 
     Even in a case of the headphone shown in FIG. 19, the gap is narrow on the supporting point  37  side of the ear hanger arm  36 , and the gap becomes widely open on the tip end side, as shown in FIG. 20, when a headphone having a standard size L in the distance from the supporting point  37  to the bending portion of the ear hanger arm  36  is mounted on a large ear, as with the case of FIG. 16, the ear portion inserted on the supporting point  37  side is pressed and pain easily occurs. Moreover, when a headphone having a size L 1  for large ears in the distance from the supporting point  37  to the bending portion of the ear hanger arm  36 , as shown in FIG. 21, is mounted on a small ear, a wide gap is formed between the headphone housing  35  and the supporting point  37 . As a result, there is a problem in that the headphone housing  35  does not come into intimate contact with the ear portion, causing sound leakage and decrease in the tone quality. 
     On the other hand, with the headphone shown in FIG. 22, the gap “g” between the annular ear-hanging section  39  and the holding section  40  is a gap which the ear portion can go through. Therefore, in the state that the headphone is inserted and fitted, there are such problems that the headphone housing  41  does not come into intimate contact with the ear portion, causing sound leakage and decrease in the tone quality, or insertion fitting becomes unstable, and headphone is easily dropped. 
     The present invention is for solving the above-described problems, and it is an object of the present invention to obtain an ear-hanging type headphone wherein insertion fitting operation of the headphone is quite easy, and insertion-fitting followingness of the headphone to the ear portion is increased without having any problem in long time use. 
     SUMMARY OF THE INVENTION 
     In order to achieve the above-described object, the headphone according to the present invention is constructed such that a rotation shaft portion is rotatably provided in a position eccentric within 45 degrees with respect to the center of the headphone body portion on the back side of the housing section, and an ear hanger arm portion is fitted to the rotation shaft portion. 
     According to the headphone constructed in this manner, the ear hanger arm portion can perform an operation alienating from the headphone body portion helically and in parallel therewith, by rotating the ear hanger arm portion about the rotation shaft portion. Therefore, in a state with the ear hanger arm portion being turned, the ear hanger arm portion is hang on the ear portion, and thereafter inversely rotated, to thereby uniformly press the ear portion on both sides of the ear hanger arm portion and the headphone body portion, with a movement of the ear hanger arm portion approaching the headphone body portion side in parallel therewith, and at the same time, the headphone body portion comes into intimate contact with the ear portion, to give a retention state of the headphone. When the headphone is removed, the ear hanger arm is turned in the direction to be alienated from the headphone body portion in parallel. Thereafter, the ear hanger arm can be removed by pulling up from the ear portion. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing the appearance of a headphone according to the present invention before mounting; 
     FIG. 2 is a side view of the headphone in FIG. 1, seen from the rear side; 
     FIG. 3 is a perspective view showing the appearance of a headphone with an ear hanger arm being turned to a mounting position; 
     FIG. 4 is a side view of the headphone in FIG. 3, seen from the rear side; 
     FIG. 5 is an enlarged sectional view of a headphone; 
     FIG. 6 shows a turn range regulation means and a rotation position lock means of a rotation shaft portion; 
     FIG. 7 is a diagram for explaining an ideal position of a rotation shaft portion with respect to a housing; 
     FIG. 8 is an enlarged sectional view of a headphone, showing another example of a rotation position lock means of a rotation shaft portion; 
     FIG. 9 is a diagram showing a locked condition of a rotation shaft portion by means of the rotation position lock means in FIG. 8; 
     FIG. 10 is a diagram showing a lock-released condition of the rotation shaft portion; 
     FIG. 11 is a perspective view showing the appearance of a headphone in another embodiment of the present invention; 
     FIG. 12 is a perspective view showing the appearance of a headphone with an ear hanger arm being turned to a mounting position in the embodiment shown in FIG. 11; 
     FIG. 13 is a perspective view showing the appearance of a headphone in another embodiment of the present invention; 
     FIG. 14 is a perspective view showing the appearance of a conventional headphone; 
     FIG. 15 is an elevational view of the conventional headphone shown in FIG. 14 in amounting condition; 
     FIG. 16 is an elevational view of another conventional headphone; 
     FIG. 17 is a plan view in the case where the headphone is mounted on a large ear; 
     FIG. 18 is a plan view in the case where the headphone is mounted on a small ear; 
     FIG. 19 is an elevational view of still another conventional headphone; 
     FIG. 20 is a side view in the case where the headphone is mounted on a large ear; 
     FIG. 21 is a side view in the case where the headphone is mounted on a small ear; and 
     FIG. 22 is a perspective view showing the appearance of a different conventional headphone. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of an ear-hanging type headphone according to the present invention will now be described with reference to the drawings. 
     FIG. 1 is a perspective view of a headphone before insertion fitting, FIG. 2 is a side view thereof, FIG. 3 is a perspective view of the headphone when it is insertion fitted to the ear portion by rotating the ear hanger arm portion, FIG. 4 is a side view thereof, and FIG. 5 is an enlarged sectional view of the headphone. 
     A speaker unit  2  is built in a headphone body portion  1  with a state being held by a fitting portion la, and a sound production section  2 a of the speaker unit  2  is covered with a sponge-like ear cushion  3 . 
     The back side of the headphone body portion  1  is covered with a housing  4  having a convex surface, and a disc-like rotation shaft portion  5  is provided in the housing  4 . The rotation shaft portion  5  is rotatably supported in the counterclockwise direction by a shaft supporting member  6  which is supported by the housing  4 , designating, as a center of rotation, O 1  eccentric by θ with respect to the normal O at the center of the headphone body portion  1 . The eccentric angle θ of the rotation shaft portion  5  is set within 45 degrees. 
     Then, an ear hanger arm  8  consisting of a plastic molded article is attached to the above-described rotation shaft portion  5  via a support  7 . The ear hanger arm  8  has a shape extending from the housing  4  side toward the front face of the ear cushion  3  on the sound production section  2   a  side, and mounted to the ear portion (auricle). Also, the tip end portion of the ear hanger arm  8  is formed in a rounded protected end portion  8   a.    
     In this manner, the ear hanger arm  8  is rotatable in the counterclockwise direction, seen from the housing  4  side, designating O 1  as a center of rotation, together with the rotation shaft portion  5 , and the rotation range is regulated. This will be described with reference to FIG.  6 . 
     On the shaft supporting member  6  is formed a guide groove  9  in a range within a predetermined angle, and a guide protrusion  10  protruding from the rotation shaft portion  5  is engaged with the guide groove  9 . Accordingly, the rotation shaft portion  5  can be turned in a range that the guide protrusion  10  is movable within the guide groove  9 . 
     When the ear hanger arm  8  is in a position before the rotation, that is, substantially in contact with the front side of the ear cushion  3  as shown in FIG.  1  and FIG. 2, the guide protrusion  10  of the rotation shaft portion  5  is in a position on one end portion  9   a  of the guide groove  9 , as shown in FIG.  6 . When the ear hanger arm  8  is turned, as shown in FIG.  3  and FIG. 4, the ear hanger arm  8  is alienated from the front side of the ear cushion  3 , to a position where the ear hanger arm  8  can be mounted on the ear portion, and the guide protrusion  10  of the rotation shaft portion  5  abuts against the other end portion  9   b  of the guide groove  9 , and regulated. At this time, there is provided a rotation position lock means in which the guide protrusion  10  is press-fitted to and engaged with a narrow portion  11  formed on the end portion of the guide groove  9 , to thereby lock the guide protrusion  10  temporarily. 
     Here, it is important that the ear hanger arm  8  is alienated from the front side of the ear cushion  3  helically and in parallel therewith, when being turned to the position mountable to the ear portion together with the rotation shaft portion  5 , and is moved helically and in parallel therewith close to the front side of the ear cushion  3 , when turned inversely together with the rotation shaft portion  5 . This is made possible by the fact that even if the ear hanger arm  8  is turned, the inclination of the ear hanger arm  8  and the plane attached to the housing  4  does not change, since the rotation shaft portion  5  is set to be rotatable centering on O 1  eccentric within 45 degrees with respect to the normal O at the center of the housing  4 , and that the rotation shaft portion  5  is located at the front upper portion of the housing  4  in the mounting position of the headphone, as shown in FIG.  7 . For example, if the rotation shaft portion  5  is provided at an eccentric angle of larger than 45 degrees with respect to the normal O at the center of the housing  4 , when the ear hanger arm  8  is turned, the ear hanger arm  8  is not alienated from the ear cushion  3  helically and in parallel therewith, and the entire ear portion cannot be pressed at a uniform holding pressure between the ear cushion  3  and the ear hanger arm  8 , and thereby causing pain due to oppression of the ear portion by means of the ear hanger arm  8 , sound leakage, and decrease in the tone quality. 
     On the other hand, the rotation shaft portion  5  is provided with a torsion spring  12  consisting of a coil spring. The torsion spring  12  is arranged in a barrel portion of the rotation shaft portion  5 , and one end portion  12   a  of the torsion spring  12  is supported on the rotation shaft portion  5  side, and the other end portion  12   b  is supported on the headphone body portion  1  side. 
     Accordingly, when the ear hanger arm  8  is turned to a position shown in FIG.  3  and FIG. 4 together with the rotation. shaft portion  5 , the torsion spring  12  is wound up, thereby the above-described guide protrusion  10  is press-fitted to and engaged with the narrow portion  11  of the guide groove  9 , being the rotation position lock means and temporarily locked, in a state with the spring force being generated. Hence, the ear hanger arm  8  is slightly pushed back in the return direction, to thereby release the lock of the guide protrusion  10  from the narrow portion  11 , so that the ear hanger arm  8  is reversed together with the rotation shaft portion  5  due to the return force of the torsion spring  12 , and returns to the position shown in FIG.  1  and FIG.  2 . Here, reference symbol  13  denotes a code pulled out from the housing  4 . 
     The mounting operation of the headphone constructed as described above is performed in the following manner. 
     At first, the ear hanger arm  8  is turned from the state shown in FIG.  1  and FIG. 2 to the turn-regulated position. Thereby, as shown in FIG.  3  and FIG. 4, the ear hanger arm  8  is temporarily locked by the rotation position lock means with the ear hanger arm  8  being alienated from the ear cushion  3  helically and in parallel therewith. If the lock of the ear hanger arm  8  is released, with the ear hanger arm  8  being hung on the ear portion in this state, the ear hanger arm  8  returns due to the spring force of the torsion spring  12 , thereby the entire ear portion is uniformly pressed on both sides of the ear hanger arm  8  and the ear cushion  3  with an adequate retention force, while the ear cushion comes into intimate contact with the ear portion to give the headphone mounting state. 
     That is to say, according to the above-described headphone of the present invention, it can be reliably fitted to the ear portion of various sizes without discomfort and sound leakage, thereby enabling improvement in the tone quality, without any pain even in long time use. 
     With regard to the removal operation of the headphone, the ear hanger arm  8  is alienated from the ear cushion  3  by turning the ear hanger arm  8  again to the turn-regulated position, to release the pressing on the ear portion, and thereafter, the ear hanger arm  8  can be easily removed by pulling up from the ear portion. 
     FIG. 8 to FIG. 10 show another example of the rotation position lock means of the ear hanger arm  8 . The same portions as the components shown in FIG. 5 are denoted by the same reference symbols. 
     According to another embodiment, spring action is imparted to the torsion spring  14  arranged in the barrel portion of the rotation shaft portion  5  in the elongation direction as well as the torsional direction, and the rotation shaft portion  5  is spring-energized by the torsion spring  14  to the position protruding with respect to the shaft supporting member  6 . Moreover, a protrusion  15  is provided in the barrel portion of the rotation shaft portion  5 , and an engagement stepped portion  16  is formed on the housing  4  side corresponding thereto. 
     The rotation position lock means is constructed such that when the ear hanger arm (not shown) winds up the torsion spring  14  to turn to the turn movement range, the protrusion  15  of the rotation shaft portion  5  is fitted to the engagement stepped portion  16  on the housing  4  side, as shown in FIG. 9, to thereby temporarily lock the ear hanger arm together with the rotation shaft portion  5 . In order to release the lock of the ear hanger arm  8 , the ear hanger arm is reversed while pressing the rotation shaft portion  5 , to thereby alienate the protrusion  15  from the engagement stepped portion  16  to release the lock. Thereafter, the ear hanger arm turns to the original position due to the return spring force of the torsion spring  14 , to perform an operation for mounting the headphone by pressing the ear portion on both sides of the ear hanger arm and the ear cushion. 
     Another embodiment of the headphone according to the present invention is shown in FIG.  11 . 
     According to this embodiment, a support  20  is rotatably fitted to a housing  19  on the side opposite to an ear cushion  18  covering the sound production section of the headphone by means of a rocker fulcrum shaft  21 , and an ear hanger arm  22  is fitted to the support  20  and arranged on the front side of the ear cushion  18 . The center of rotation O 1  of this rocker fulcrum shaft  21  is located in a position eccentric by about 45 degrees with respect to the normal O at the center of the headphone. The ear hanger arm  22  in this case is also constructed such that when returning to the original position from the turned position, it returns by means of a spring member (not shown) arranged in the housing  19 . 
     The headphone constructed in this manner operates such that when the ear hanger arm  22  is turned, the ear hanger arm  22  can be alienated from the front side of the ear cushion  18  helically and in parallel therewith, as shown in FIG. 12, thereby the entire ear portion can be uniformly pressed on both sides of the ear hanger arm  22  and the ear cushion  18 , as with the headphone shown in FIG. 1, and the ear cushion  18  comes into intimate contact with the ear portion, to give a headphone having no problem such as sound leakage and decrease in the tone quality. 
     Still another embodiment of the headphone is shown in FIG.  13 . 
     According to this embodiment, a support  25  is fitted to a housing  24  on the side opposite to the ear cushion  23  covering the sound production section of the headphone so as to face the front side of the ear cushion  23 , and an ear hanger arm  26  is rotatably supported on the fixed part  25  and arranged on the front side of the ear cushion  23 . 
     In the case of the above-described headphone, the ear hanger arm  26  is turned toward the outer peripheral side substantially in parallel with the front side of the ear cushion  23 , as shown in a virtual line, and hence in a state that the headphone is mounted, the entire ear portion is uniformly pressed on both sides of the ear hanger arm  26  and the ear cushion  23 , and the ear cushion  23  comes into intimate contact with the ear portion, to give a headphone having no problem such as sound leakage and decrease in the tone quality. 
     Having described preferred embodiments of the invention with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments and that various changes and modifications could be effected therein by one skilled in the art without departing from the spirit or scope of the invention as defined in the appended claims.