Patent Description:
A known typical headphone is worn on the user's head, covering the user's right and left ears. A known example of such a headphone includes: a pair of housings being placed on the right and left ears; a headband being placed on the head; and connectors provided to ends of the headband, the housings each being rotatably connected to corresponding one of the connectors (see, for instance, Patent Literature <NUM>).

The pair of housings of the headphone disclosed in Patent Literature <NUM> each include a body containing a speaker unit and a hanger supporting the body. Respective sound-emitting surfaces of the bodies of the housings, which face each other when the headphone is in a normal use state, can be directed rearward by oppositely rotating the housings. In other words, the housings of the headphone are rotatable by <NUM> degrees with respect to the normal use state. <CIT> discloses in a headphone with rotable speakers, a stopper structure determining a movable range of a hanger being always biased by a torsion coil spring. <CIT> discloses in a headphone with rotable speakers, a biasing force of a spring member, which does not act a restoring force for restoring a speaker to a reference position. <CIT> discloses in a headphone with rotable speakers, a stopper having a spring property, which switches a fixation state between an arm and a holder and, by releasing the fixation state, allows the arm and the holder to rotate around a shaft. There is no restoring force for restore a speaker unit to a reference position. <CIT> discloses headphones with speakers rotatable around a rotation axis extending along top-bottom direction and comprising restoring portions configured to apply a restoring force on the speakers to force them to return to a reference position at which sound-emitting surfaces of the speakers face each other.

When a typical user uses such a headphone, the headphone is worn in the normal use state. In contrast, specific users such as a DJ (Disc Jockey), who have to monitor music currently played at a site and music to be played next, wear the headphone with one of the right and left housings being put on ear and the other being put along a part other than ear.

In view of the wearing conditions of the users, the housings and the hangers may be configured to be automatically restored to the normal use state with a use of a biasing member (e.g. a spring) after being rotated. According to the above arrangement, a biasing force applied by the biasing member acts to hold a part of a human body (e.g. a head) with the housings after the headphone is worn. In addition, the biasing force reduces the chance of unexpected detachment of the housings from ears, allowing the headphone to be stably worn even when the above specific users use the headphone.

However, resistance against the biasing force is continuously applied by the biasing member when the housings of the headphone arranged as the above are stored in a storing case or the like after being rotated by <NUM> degrees from the normal use state, so that the biasing force may be weakened. In addition, the housings automatically return to the normal use state even when the above specific users hope that the housings should be kept rotated by <NUM> degrees in using the headphone, deteriorating the usability for the specific users.

In view of the above problems, an object of the invention is to provide a more user-friendly headphone.

A headphone according to an aspect of the invention includes the features of claim <NUM>. Advantageous embodiments are subject-matter of the dependent claims.

A first exemplary embodiment of the invention will be described with reference to the attached drawings.

<FIG> is a perspective view showing a front side of a headphone <NUM> according to the first exemplary embodiment.

The headphone <NUM> according to the first exemplary embodiment is configured to be worn on the user's head and output sound to the user's ears. As shown in <FIG>, the headphone <NUM> includes a headband <NUM>, a pair of sound emitters <NUM> (<NUM>, 3R), and a pair of connectors <NUM> (<NUM>, 4R) provided to right and left ends of the headband <NUM>.

One of the features of the headphone <NUM> is that the sound emitters <NUM>, which are each supported in a manner rotatable around a rotation axis AX3 along a top-bottom direction, are configured to switch a mode in which the sound emitters <NUM> are each biased toward a reference position (i.e. a position at which sound-emitting surfaces <NUM> face each other) and a mode in which the sound emitters <NUM> are not biased toward the reference position.

It should be noted that "front" and "rear" hereinbelow refer to front and rear with respect to a user who wears the headphone <NUM>. Likewise, "up" and "down" refer to up and down with respect to the user and "right" and "left" refer to right and left with respect to the user.

Components of the headphone <NUM> will be described below.

The headband <NUM> is an arched member wearable on the head. The headband <NUM> is arched from the sound emitter <NUM> (<NUM>) corresponding to the left ear and the sound emitter <NUM> (3R) corresponding to the right ear. A left end of the headband <NUM> is provided with the connector <NUM> connected with the sound emitter <NUM> and a right end of the headband <NUM> is provided with the connector 4R connected with the sound emitter 3R. It should be noted that an extension/retraction mechanism capable of extension and retraction along the arched shape of the headband <NUM> may be provided near each of the right and left ends of the headband <NUM>.

The pair of sound emitters <NUM> (right and left sound emitters are denoted by 3R and <NUM>, respectively) are configured to output a sound corresponding to an inputted audio signal. The sound emitters <NUM>, 3R each include a housing <NUM>, a sound-emitting unit <NUM>, a pad <NUM>, and a hanger <NUM>.

The housing <NUM>, which is cylindrical, contains the sound-emitting unit <NUM> (e.g. a speaker) therein. It should be noted that one of the right and left housings <NUM> is provided with an input cord (not shown) connected to an acoustic device. The acoustic device outputs audio signal for the left ear and audio signal for the right ear, one of which is inputted to the sound-emitting unit <NUM> in corresponding one of the housings <NUM> through the input cord. Meanwhile, the other audio signal is inputted to the sound-emitting unit <NUM> in the other housing <NUM> through a signal wire (not shown) in the headband <NUM>. It should be noted that the audio signal(s) may be wirelessly received without using the input cord.

The pad <NUM> is attached to the sound-emitting surface <NUM> of the housing <NUM>, through which sound is outputted from the sound-emitting unit <NUM>. The pad <NUM> may be made of a material with cushioning properties (e.g., low-resilience urethane) to be fitted well on the head when the pad <NUM> is in contact with the head.

The hanger <NUM> supports the housing <NUM> while being connected to the corresponding connector <NUM>. The hanger <NUM> includes a first connecting portion <NUM> at a lower end and a second connecting portion <NUM> at an upper end.

The first connecting portion <NUM> is connected to a surface <NUM> of the housing <NUM> opposite the sound-emitting surface <NUM>. The first connecting portion <NUM> supports housing <NUM> so that the housing <NUM> is rotatable around a rotation axis AX1 that extends along a front-back direction.

The second connecting portion <NUM> is connected to a connecting member <NUM> of the connector <NUM> to connect the hanger <NUM> with the connector <NUM>. The second connecting portion <NUM> includes a pair of cylindrical portions <NUM> that are spaced in the front-back direction by a predetermined gap. A fixing unit FM is inserted into the cylindrical portions <NUM> and a barrel portion <NUM> (see <FIG>) of the connecting member <NUM> with the barrel portion <NUM> being disposed between the cylindrical portions <NUM>, so that the hanger <NUM> is supported by the connecting member <NUM> in a manner rotatable around a rotation axis AX2 extending along the front-back direction.

It should be noted that, though detailed later, the connecting member <NUM>, which is rotatable around the rotation axis AX3 along the top-bottom direction, allows the hanger <NUM> and, consequently, sound emitter <NUM> to rotate around the rotation axis AX3 when the hanger <NUM> is connected to the connector <NUM>.

<FIG> is an exploded perspective view showing the connector <NUM> (<NUM>). It should be noted that, though <FIG> shows the structure of the connector <NUM>, the connector 4R is similarly structured.

The connectors <NUM> (right and left connectors are denoted by 4R and <NUM>, respectively) connect the headband <NUM> to the hangers <NUM> (sound emitters <NUM>). As shown in <FIG>, each of the connectors <NUM> includes a support <NUM> that supports the hanger <NUM> so that the hanger <NUM> is rotatable, a restoring portion <NUM> configured to apply on the hanger <NUM> a restoring force to the reference position, and a switcher <NUM> configured to switch a state in which the restoring force is applied and a state in which the restoring force is not applied.

It should be noted that the right connector <NUM> (4R), which is bilaterally symmetrical to the connector <NUM> (<NUM>), has the same structure as that of the connector <NUM> (<NUM>). Accordingly, the left connector <NUM> (<NUM>) will be described below.

The support <NUM>, which is attached to the headband <NUM>, supports the hanger <NUM> so that the hanger <NUM> is rotatable. The support <NUM> includes the connecting member <NUM>, a first support member <NUM>, a cover <NUM>, a fixing member <NUM> and a second support member <NUM>. Among the above, the first support member <NUM>, the cover <NUM>, the fixing member <NUM> and the second support member <NUM> define the support member of the invention.

<FIG> is a perspective view showing the connecting member <NUM> from above. It should be noted that <FIG> also shows the restoring portion <NUM> (a biasing member <NUM>) engaged with the connecting member <NUM>.

The connecting member <NUM>, which is connected to the second connecting portion <NUM>, allows the rotation of the hanger <NUM> around the rotation axis AX2. As shown in <FIG>, the connecting member <NUM> includes the barrel portion <NUM> at a lower part and a held portion <NUM> at an upper part.

The barrel portion <NUM> includes a through hole <NUM> penetrating through the barrel portion <NUM> in the front-back direction. The fixing unit FM (see <FIG>) is inserted into the through hole <NUM>.

The held portion <NUM>, whose outer diameter is larger at an upper part than a lower part thereof, is held by the first support member <NUM> from right and left sides. The held portion <NUM> includes a flange <NUM>, a projection <NUM>, an opening <NUM>, a recess <NUM>, and a projection <NUM>.

The flange <NUM> is an annular (as viewed from above) part at an upper end of the held portion <NUM>.

The projection <NUM> projects downward from a part of a peripheral edge of the flange <NUM>. The projection <NUM> is configured to be in contact with one of a pair of restricting portions <NUM>, <NUM> (see <FIG>) of a second holder piece <NUM> of the first support member <NUM> when the connecting member <NUM> is rotated. The restricting portions <NUM>, <NUM> define a rotation range of the connecting member <NUM> around the rotation axis AX3, as detailed later.

The opening <NUM> penetrates through the held portion <NUM> in the top-bottom direction to be in communication with the through hole <NUM>.

The recess <NUM> is dented downward at a part of a periphery of the opening <NUM>. An end (extending portion <NUM>) of the later-described biasing member <NUM> is received by the recess <NUM>.

The projection <NUM> is disposed inside a pair of restricting portions <NUM>, <NUM> (see <FIG>) of the later-described piece member <NUM>. The projection <NUM> is configured to be in contact with one of the pair of restricting portions <NUM>, <NUM> when the connecting member <NUM> is rotated around the rotation axis AX3.

As shown in <FIG>, the first support member <NUM> is a component, in combination with the cover <NUM>, to attach the connecting member <NUM> to the second support member <NUM> so that the connecting member <NUM> is rotatable. The first support member <NUM> includes a first holder piece <NUM> and a second holder piece <NUM>. These holder pieces <NUM>, <NUM> are combined by a pair of fixing members <NUM>, which are inserted along a right-left direction and fixed to the second support member <NUM>. It should be noted that the fixing members <NUM> are screws in the first exemplary embodiment.

When the headphone <NUM> is worn by a user, the first holder piece <NUM> is located at a side of the headphone <NUM> facing the user and the second holder piece <NUM> is located at a side opposite the user.

The first holder piece <NUM> and the second holder piece <NUM> include semi-circular open portions <NUM>, <NUM>, respectively, in which a part of the held portion <NUM> below the flange <NUM> and the projection <NUM> is fitted. In addition, the first holder piece <NUM> includes a recess <NUM> formed along the open portion <NUM>. The second holder piece <NUM> includes a recess <NUM> formed along the open portion <NUM>. When the first holder piece <NUM> and the second holder piece <NUM> are combined, the held portion <NUM> of the connecting member <NUM> is held by the first holder piece <NUM> and the second holder piece <NUM> from right and left sides. At this time, a part of the flange <NUM> near the first holder piece <NUM> is received within the recess <NUM> and a part of the flange <NUM> near the second holder piece <NUM> is received within the recess <NUM>. The connecting member <NUM> is thus rotatably supported by the first support member <NUM>.

It should be noted that the second holder piece <NUM> includes the pair of upward-projecting restricting portions <NUM>, <NUM> in the recess <NUM>. When the connecting member <NUM> is combined with the first support member <NUM>, the projection <NUM> is located between the pair of restricting portions <NUM>, <NUM>. The connecting member <NUM> is rotatable with respect to the first support member <NUM> within a range defined by contact points of the projection <NUM> to the first and second restricting portion <NUM> and <NUM>. The restricting portions <NUM>, <NUM> thus define the rotation range of the connecting member <NUM>. The position of the sound emitter <NUM> (e.g. sound emitter <NUM>) when the projection <NUM> is in contact with one of the restricting portions <NUM>, <NUM> defines the reference position at which the sound-emitting surface <NUM> of the sound emitter <NUM> squarely faces the other sound emitter (e.g. the sound emitter 3R).

Being combined with the first support member <NUM>, the cover <NUM> is fixed to the second support member <NUM> (extending portion <NUM>) with the fixing member <NUM> such as a screw. Thus, the connecting member <NUM>, the first support member <NUM>, the cover <NUM>, and the second support member <NUM> are integrated.

The cover <NUM> includes two holes <NUM>, each of which receives corresponding one of the fixing members <NUM>, and a recess <NUM> to be combined with the first support member <NUM>.

The second support member <NUM> is attached to an end of the headband <NUM>. The first support member <NUM> and the cover <NUM> are attached to the second support member <NUM>. As shown in <FIG>, the second support member <NUM> includes an extending portion <NUM> extending along an arch of the headband <NUM>, and a bent portion <NUM> bent at an end of the extending portion <NUM> to extend substantially in the right-left direction.

An arrangement base <NUM>, on which a later-described operation member <NUM> is placed, is provided in a form of a cylinder projecting upward on the bent portion <NUM>. The arrangement base <NUM> includes a hole <NUM> substantially at a center thereof, and a pair of guides <NUM> arranged in a line extending in opposite directions across the hole <NUM>. The pair of guides <NUM> each define a hole for receiving a boss <NUM> of corresponding one of later-described restricting members <NUM> to restrict a movement of the restricting members <NUM> in later-described ±D2 directions.

It should be noted that a receiver <NUM> (see <FIG>) for receiving a part of the restoring portion <NUM> and the switcher <NUM> is provided on a bottom side of the bent portion <NUM>.

The restoring portion <NUM> is configured to apply a biasing force (restoring force) to the connecting member <NUM> so that the sound emitter <NUM> is located at the reference position when the sound emitter <NUM> is rotated while the later-described switcher <NUM> is enabled. As shown in <FIG>, the restoring portion <NUM> includes the biasing member <NUM>, a washer <NUM>, and a fixing member <NUM>. It should be noted that the restoring portion <NUM> is "enabled" (in an enabled state) when the biasing force applied by the biasing member <NUM> is capable of acting on the connecting member <NUM>, and the restoring portion <NUM> is "disabled" (in a disabled state) when the biasing force is incapable of acting on the connecting member <NUM>.

The biasing member <NUM> is configured to generate the restoring force and is in a form of a torsion coil spring in the first exemplary embodiment. The biasing member <NUM> includes a coil <NUM> having a central axis coaxial with the rotation axis AX3, and extending portions <NUM>, <NUM> extending from both ends of the coil <NUM> in mutually different directions.

The coil <NUM> is disposed to surround a boss <NUM> projecting from a bottom side of the piece member <NUM> of the later-described switcher <NUM>. The biasing member <NUM> is attached to the piece member <NUM> by attaching the washer <NUM> and the fixing member <NUM> onto the boss <NUM> from below with the boss <NUM> being surrounded by the coil <NUM>.

The extending portion <NUM> (i.e. lower one of the extending portion <NUM>, <NUM>) is inserted into the recess <NUM> of the connecting member <NUM>. The extending portion <NUM> (i.e. upper one of the extending portion <NUM>, <NUM>) is locked by a locking portion <NUM> (see <FIG>) projecting from the piece member <NUM>.

The switcher <NUM> is configured to switch the enabled state in which the restoring portion <NUM> is enabled to allow the restoring force to act on the connecting member <NUM> (and consequently on the hanger <NUM>) and the disabled state in which the restoring portion <NUM> is disabled to keep the restoring force from acting on the connecting member <NUM>. As shown in <FIG>, the switcher <NUM> includes the piece member <NUM>, the operation member <NUM>, a washer <NUM>, an O-ring <NUM>, a fixing member <NUM>, and the pair of restricting members <NUM>. It should be noted that the switcher of the invention refers to a combination of the switcher <NUM> and the second support member <NUM> in the first exemplary embodiment. In other words, the second support member <NUM> is a component common to the support and the switcher of the invention.

<FIG> is a perspective view showing the piece member <NUM> from below. It should be noted that the biasing member <NUM> is also shown in <FIG>.

The piece member <NUM>, which is substantially circular as viewed from above, is disposed in the receiver <NUM> in a manner rotatable around the rotation axis AX3. The restoring portion <NUM> is in the disabled state when the rotation of the piece member <NUM> is allowed and is in the enabled state when the rotation of the piece member <NUM> is restricted.

As shown in <FIG>, the piece member <NUM> includes the boss <NUM>, the locking portion <NUM>, the restricting portions <NUM>, <NUM> and a projection <NUM>.

The boss <NUM> projects from the center of a bottom side 71BS of the piece member <NUM>. As described above, the coil <NUM> of the biasing member <NUM> is disposed around the boss <NUM>. The boss <NUM> includes a screw hole <NUM>, to which the fixing member <NUM> for attaching the biasing member <NUM> to the boss <NUM> is fixed via the washer <NUM>.

The locking portion <NUM> locks the upper extending portion <NUM> of the biasing member <NUM>. The locking portion <NUM> projects from the bottom side 71BS at a position apart from the boss <NUM>.

The restricting portions <NUM>, <NUM> and the projection <NUM> project from a periphery of the bottom side 71BS. Among the above, the restricting portions <NUM>, <NUM> are substantially symmetrical across the boss <NUM> and are configured to be in contact with the projection <NUM>. In other words, like the restricting portions <NUM> and <NUM>, the restricting portions <NUM>, <NUM> are a pair of restricting portions that define the rotation range of the connecting member <NUM>.

Further, as shown in <FIG> and <FIG>, the piece member <NUM> includes a pair of rising portions <NUM> and a pair of cutouts <NUM> defined by peripheral edges of the pair of rising portions <NUM>.

The pair of rising portions <NUM> rise upward from a periphery of an upper side <NUM> of the piece member <NUM>. The rising portions <NUM> are divided by the pair of cutouts <NUM> symmetrical across a center of the upper side <NUM>. In other words, the pair of rising portions <NUM> are symmetrical across the center. The pair of restricting members <NUM> are disposed in the pair of rising portions <NUM>.

It should be noted that the peripheral edges of the pair of rising portions <NUM> defining the cutouts <NUM> and intersecting the upper side <NUM> are abutment portions <NUM> configured to be in contact with the pair of restricting members <NUM>.

The operation member <NUM>, which is a drive member for moving the restricting members <NUM>, is in a form of a dial in the first exemplary embodiment. As shown in <FIG>, the operation member <NUM> is placed to cover the arrangement base <NUM> of the second support member <NUM> from above. Specifically, the operation member <NUM> is rotatably attached to the arrangement base <NUM> with the fixing member <NUM> (e.g. a screw) inserted from below into the hole <NUM> through the washer <NUM> and the O-ring <NUM>.

<FIG> is a perspective view showing the operation member <NUM> from below.

As shown in <FIG>, the operation member <NUM> includes a boss <NUM>, which has a hole <NUM> for the fixing member <NUM> to be fixed therein, at the center of a bottom side 72BS, and a pair of guide grooves <NUM> that are symmetrical across the boss <NUM>.

The pair of guide grooves <NUM> each extend in a curve from a part near the center of the bottom side 72BS toward an outside. Specifically, each of the guide grooves <NUM> define a spiral (volute) around the boss <NUM>. The boss <NUM> of corresponding one of the restricting members <NUM> is inserted into each of the guide grooves <NUM>. In accordance with the rotation of the operation member <NUM>, the guide grooves <NUM> guides the movement of each of the restricting members <NUM> with the bosses <NUM> being inserted through the guide <NUM> in directions orthogonal to the rotation axis AX3 (specifically in radial directions from the center of the piece member <NUM>). It should be noted that the guide grooves <NUM> are not necessarily spiral but may linearly extend from an inner side to an outer side of the bottom side 72BS as long as the guide grooves <NUM> are capable of moving the restricting members <NUM> in directions as described above.

The pair of restricting members <NUM> are configured to move in accordance with the rotation of the operation member <NUM> to restrict or allow the rotation of the piece member <NUM>, thereby enabling or disabling the restoring portion <NUM>. As shown in <FIG>, the pair of restricting members <NUM> are disposed between the piece member <NUM> and the second support member <NUM>.

<FIG> is a perspective view showing the pair of restricting members <NUM> whose bosses <NUM> are inserted into the corresponding one of the guide grooves <NUM> of the operation member <NUM>.

As shown in <FIG> and <FIG>, each of the restricting members <NUM> is an integrated component including the boss <NUM> and a restricting portion <NUM>.

The boss <NUM> corresponds to the engagement portion of the invention. An upper end of the boss <NUM> is inserted through the guide <NUM> of the second support member <NUM> to be received in the guide groove <NUM> of the operation member <NUM>. The bosses <NUM> move in the radial directions in accordance with the rotation of the operation member <NUM>. The bosses <NUM> are linearly moved while being guided by the guides <NUM>.

When the bosses <NUM> are moved outward in the radial directions, the restricting portions <NUM> are received in the cutouts <NUM> to be contactable with the abutment portions <NUM>. In this state, when the piece member <NUM> is to be rotated around the rotation axis AX3, the abutment portions <NUM> are brought into contact with the respective restricting portions <NUM> to restrict the rotation of the piece member <NUM>. In this case, since the piece member <NUM> is unable to rotate together with the connecting member <NUM>, the biasing force of the biasing member <NUM> is capable of acting on the connecting member <NUM>.

Meanwhile, when the restricting portion <NUM> is located inside the rising portions <NUM>, since the abutment portions <NUM> are not in contact with the restricting portions <NUM>, the rotation of the piece member <NUM> is not restricted by the restricting members <NUM>. In this case, since the piece member <NUM> is rotatable coaxially with the biasing member <NUM> and the connecting member <NUM>, the biasing force (restoring force) of the biasing member <NUM> is incapable of acting on the connecting member <NUM>.

<FIG> shows a rotation direction (+D1 direction) of the operation member <NUM> when the restoring portion <NUM> is enabled. <FIG> shows a moving state of the restricting members <NUM> when the operation member <NUM> is rotated in the +D1 direction shown in <FIG>.

When the restoring portion <NUM> is disabled, the operation member <NUM> is capable of rotation in the +D1 direction (i.e. a circumferential direction around the rotation axis AX3 shown in <FIG>). When the operation member <NUM> is rotated in the +D1 direction, each of the restricting members <NUM>, whose boss <NUM> is located in the guide groove <NUM> near the center of the operation member <NUM>, moves toward an outside of the operation member <NUM> (i.e. outside in the radial direction, +D2 direction shown in <FIG>) along each of the guides <NUM> of the second support member <NUM>, as shown in <FIG> and <FIG>.

<FIG> is a perspective view showing a positional relationship between each of the restricting members <NUM> and the piece member <NUM>.

When the operation member <NUM> is rotated in the +D1 direction to fully move each of the restricting members <NUM> in the +D2 direction, the restricting portion <NUM> of each of the restricting members <NUM> is located in the corresponding one of the cutouts <NUM> of the piece member <NUM> and thus is contactable with the abutment portions <NUM> as shown in <FIG>. In this state, even when the piece member <NUM> is to be rotated together with the connecting member <NUM> connected with the hanger <NUM>, the rotation of the piece member <NUM> is restricted by a contact between the restricting portions <NUM> and respective abutment portions <NUM>. Accordingly, the biasing force (restoring force) of the biasing member <NUM>, whose extending portion <NUM> is locked by the piece member <NUM>, is capable of acting on the connecting member <NUM> engaged with the extending portion <NUM>. The position of the restricting members <NUM> in this state is a restricting position according to the invention.

It should be noted that the hanger <NUM> and the connecting member <NUM> are rotatable around the rotation axis AX3 toward the rear side by <NUM> degrees with respect to the reference position at which sound-emitting surfaces <NUM> of the respective sound emitters <NUM> face each other. As described above, the rotation range of the connecting member <NUM> is defined by the projection <NUM> and the pair of restricting portions <NUM>, <NUM>, and the projection <NUM> and the pair of restricting portions <NUM>, <NUM>.

The biasing member <NUM> applies the restoring force on the connecting member <NUM> when the hanger <NUM> and the connecting member <NUM> are rotated in a direction where the sound-emitting surface <NUM> of the sound emitter <NUM> face the rear side. Accordingly, the sound emitter <NUM> can be easily positioned at the reference position, so that the headphone <NUM> can be easily maintained in an orientation for a typical user to use the headphone <NUM>.

<FIG> shows a rotation direction (-D1 direction) of the operation member <NUM> when the restoring portion <NUM> is disabled. <FIG> shows a moving state of the restricting members <NUM> when the operation member <NUM> is rotated in the -D1 direction shown in <FIG>.

When the restoring portion <NUM> is enabled as described above, the operation member <NUM> is rotatable in the -D1 direction shown in <FIG> (i.e. an opposite direction to the +D1 direction). When the operation member <NUM> is rotated in the -D1 direction, each of the restricting members <NUM>, whose boss <NUM> is located in the guide groove <NUM> near the outer periphery of the operation member <NUM>, moves toward an inside of the operation member <NUM> (i.e. inside in the radial direction, -D2 direction shown in <FIG>) along each of the guides <NUM> as shown in <FIG> and <FIG>.

When the operation member <NUM> is rotated in the -D1 direction to fully move each of the restricting members <NUM> in the -D2 direction, the restricting portions <NUM> are located inside the pair of rising portions <NUM> as shown in <FIG>. In this state, even when the piece member <NUM> is rotated together with the connecting member <NUM> connected with the hanger <NUM>, the abutment portions <NUM> are not in contact with the respective restricting portions <NUM>. Accordingly, the biasing member <NUM> and the piece member <NUM> are rotated integrally with the connecting member <NUM>, so that the biasing force (restoring force) of the biasing member <NUM> no more acts on the connecting member <NUM>. Thus, the connecting member <NUM> and the hanger <NUM> (sound emitter <NUM>) are capable of freely rotating within the rotation range. The position of each of the restricting members <NUM> in this state is an allowing position according to the invention.

The headphone <NUM> according to the first exemplary embodiment as described above provides the following advantage(s).

The headphone <NUM> includes the headband <NUM>; the sound emitter <NUM> including a sound-emitting unit <NUM> therein, and the connector <NUM> connecting the sound emitter <NUM> to the headband <NUM>. Among the above, the connector <NUM> includes the support <NUM> for supporting the sound emitter <NUM> (hanger <NUM>) so that the sound emitter <NUM> is rotatable around the rotation axis AX3 along the top-bottom direction in the rotation range including the reference position, the restoring portion <NUM> for applying the restoring force for restoration to the reference position on the sound emitter <NUM>, and the switcher <NUM> for switching the enabled state in which the restoring force is capable of acting on the sound emitter <NUM> and the disabled state in which the restoring force is incapable of acting on the sound emitter <NUM>.

The above arrangement allows switching between the state in which the sound emitter <NUM> is automatically restored to the reference position, and the state in which sound emitter <NUM> is freely rotatable. Accordingly, when a typical user uses the headphone <NUM>, the restoring portion <NUM> is enabled so that the sound emitters <NUM> can be easily disposed on the right and left ears of the user. Alternatively, when a specific user (e.g. a DJ) uses the headphone <NUM> with one of the sound emitters <NUM> being put on one ear and the other one of sound emitters <NUM> being held along another part of the user, the biasing force applied on the sound emitters <NUM> allows the headphone <NUM> to be worn so that the sound emitters <NUM> hold the body (e.g. head) of the user. Accordingly, the detachment of the sound emitters <NUM> from ear can be restrained, allowing the user to stably wear the headphone <NUM>. On the other hand, by disabling the restoring portion <NUM>, the sound emitters <NUM> can be arranged so that the sound-emitting surfaces <NUM> each face the rear side when the headphone <NUM> is stored, allowing the headphone <NUM> to be stored in a compact space. Further, since the enabled state with the restoring portion <NUM> being enabled and the disabled state with the restoring portion <NUM> being disabled can be switched, the headphone <NUM> can be used in a manner suitable for each of various usages of the user. The user-friendliness of the headphone <NUM> can thus be improved.

The support <NUM> includes the connecting member <NUM> connected to the hanger <NUM> of the sound emitter <NUM> and engaged with an end (extending portion <NUM>) of the biasing member <NUM> of the restoring portion <NUM>, and the support member (the first support member <NUM>, the cover <NUM>, and the second support member <NUM>) attached to the headband <NUM> to support the connecting member <NUM> so that the connecting member <NUM> is rotatable. Further, the switcher <NUM> includes a piece member <NUM> engaged with the other end (extending portion <NUM>) of the biasing member <NUM>, the restricting members <NUM> for restricting the rotation of the piece member <NUM>, and the operation member <NUM> for moving the restricting members <NUM> to the restricting position and the allowing position. Accordingly, by restricting the rotation of the piece member <NUM>, the enabled state and the disabled state of the restoring portion <NUM> can be reliably switched. The above arrangement can thus reliably improve the user-friendliness of the headphone <NUM>.

The operation member <NUM>, which is a dial operable by the user, moves the restricting members <NUM> to one of the restricting position and the allowing position. Accordingly, the user can easily switch the enabled state and the disabled state of the restoring portion <NUM> by operating the operation member <NUM>.

The restricting members <NUM> are configured to move along the radial directions (directions orthogonal to the rotation axis AX3) of the piece member <NUM>. The piece member <NUM> includes the abutment portions <NUM> to be in contact with the restricting members <NUM> when the restricting members <NUM> are at the restricting position. The rotation of the piece member <NUM> can thus be reliably restricted and, consequently, the restoring portion <NUM> can be reliably switched to the enabled state by locating the restricting members <NUM> at the restricting position.

The piece member <NUM> includes the rising portions <NUM> standing on the upper side <NUM> facing the restricting members <NUM>. The allowing position is located inside (i.e. near the center) of the piece member <NUM> with respect to the rising portions <NUM>. The restricting position is located near the outside of the piece member <NUM> with respect to the rising portions <NUM>. The restricting members <NUM> can thus be located at the position not in contact with the piece members <NUM> by locating the restricting members <NUM> at the allowing position, so that the rotation of the piece member <NUM> can be reliably restricted. The piece member <NUM> to be rotated can thus be brought into contact with the restricting members <NUM> when the restricting members <NUM> are located at the restricting position, so that the rotation of the piece member <NUM> can be reliably restricted. Accordingly, the enabled state and the disabled state of the restoring portion <NUM> can be reliably switched by moving the restricting members <NUM> to the allowing position and the restricting position.

The abutment portions <NUM> of the piece member <NUM> to be brought into contact with the restricting members <NUM> are defined by the peripheral edges of the cutouts <NUM> defined in the rising portion <NUM>. The abutment portions <NUM> can thus be reliably brought into contact with the restricting members <NUM> (restricting portions <NUM>) when the piece member <NUM> is rotated with the restricting members <NUM> being located inside the cutouts <NUM> (restricting position). Accordingly, the rotation of the piece member <NUM> can be reliably restricted, so that the biasing force (restoring force) of the restoring portion <NUM> can be reliably applied on the connecting member <NUM> and, consequently, on the hanger <NUM> of the sound emitter <NUM>.

The second support member <NUM> includes the guides <NUM> through which the bosses <NUM> (the engagement portions) of the restricting members <NUM> are inserted to guide the movement of the restricting members <NUM>. The linear movement of the restricting members <NUM> can thus be facilitated, so that the restricting members <NUM> can be reliably moved to the restricting position or the allowing position. Particularly, since the operation member <NUM> is in a form of a dial in the first exemplary embodiment, the rotation of the operation member <NUM> can be reliably converted to the linear movement of the restricting members <NUM> by the linearly extending guides <NUM>. Accordingly, the enabled state and the disabled state of the restoring portion <NUM> can be reliably switched by the user's operation on the operation member <NUM>.

The operation member <NUM> is a dial capable of rotation around the rotation axis AX3. Further, the operation member <NUM> includes the guide grooves <NUM> each configured to receive corresponding one of the respective bosses <NUM> and move the restricting members <NUM> in the radial directions of the piece member <NUM> in response to the rotation of the operation member <NUM>. The restricting members <NUM> can thus be reliably moved in the radial directions of the piece member <NUM> in response to the rotation of the operation member <NUM>, so that the restricting members <NUM> can be reliably located at the allowing position and the restricting position. Accordingly, the enabled state and the disabled state of the restoring portion <NUM> can be reliably switched by the user's operation on the operation member <NUM>.

Two restricting members <NUM> are disposed across the center of the piece member <NUM> (i.e. the rotation axis AX3). The stability in restricting the rotation of the piece member <NUM> by the restricting members <NUM> can thus be enhanced as compared with an instance provided with a single restricting member <NUM>. Accordingly, the rotation of the piece member <NUM> can be reliably and stably restricted.

The restoring portion <NUM> includes the biasing member <NUM> in a form of a torsion coil spring. The restoring portion <NUM> configured to connect the connecting member <NUM> and the piece member <NUM> can thus be relatively easily provided. Accordingly, the structure of the connector <NUM> can be simplified.

Next, a second exemplary embodiment of the invention will be described.

A headphone according to the second exemplary embodiment is structurally the same as the headphone <NUM> except that the sound emitters <NUM> are capable of being locked at an angle (rotation angle) desired by a user. It should be noted that the same or substantially the same parts as already described will be denoted by the same reference characters hereinbelow for omission of the description thereof.

<FIG> is an exploded perspective view showing a structure of a connector 4A of a headphone 1A according to the second exemplary embodiment.

The headphone 1A according to the second exemplary embodiment is structurally and functionally the same as the headphone <NUM> except for a pair of connectors 4A, which are provided in place of the pair of connectors <NUM>.

Each of the pair of connectors 4A is provided to corresponding one of the right and left ends of the headband <NUM> in the same manner as the pair of connectors <NUM> and is configured to support corresponding one of the sound emitters <NUM> (hangers <NUM>) so that the sound emitters <NUM> (hangers <NUM>) are rotatable around the rotation axis AX3 along the top-bottom direction, thereby connecting the headband <NUM> and the sound emitters <NUM>. As shown in <FIG>, each of the connectors 4A includes a support 5A, a restoring portion 6A, and a switcher 7A.

Among the above, the restoring portion 6A includes the biasing member <NUM> and the washer <NUM> as the restoring portion <NUM> but does not include the fixing member <NUM>.

It should be noted that the connector 4A located on the left side and the connector 4A located on the right side with respect to the headband <NUM> are symmetrically arranged but of the same structure in other respects. Accordingly, the connector 4A located on the left side will be described and the description on the connector 4A located on the right side will be omitted hereinbelow.

As in the support <NUM>, the support 5A is attached to the headband <NUM> with the hanger <NUM> being connected, thereby supporting the hanger <NUM> (and, consequently, the sound emitter <NUM>) so that the hanger <NUM> (and, consequently, the sound emitter <NUM>) is rotatable. The support 5A includes a connecting member 51A, the first support member <NUM>, the cover <NUM>, the fixing member <NUM> and a second support member 55A.

As in the connecting member <NUM>, the connecting member 51A is connected to the second connecting portion <NUM> (see <FIG>) so that the hanger <NUM> is rotatable around the rotation axis AX2 (see <FIG>) along the front-back direction. The connecting member 51A includes the barrel portion <NUM> at a lower part and a held portion <NUM> at an upper part.

The held portion <NUM> includes an annular flange <NUM> extending radially outward from the circumference of the held portion <NUM>, a projection <NUM> and a recess <NUM> provided on the flange <NUM>, and a shaft portion <NUM>.

The projection <NUM> projects from an upper side of the flange <NUM>. As in the projection <NUM>, the projection <NUM> is disposed inside the pair of restricting portions <NUM>, <NUM> (see <FIG>) of a piece member 71A. The projection <NUM> is configured to be in contact with one of the pair of restricting portions <NUM>, <NUM> when the connecting member <NUM> is rotated around the rotation axis AX3.

As in the recess <NUM>, the recess <NUM> receives the extending portion <NUM> of the biasing member <NUM> to lock the extending portion <NUM>.

The shaft portion <NUM> is a cylindrical member standing upward from a bottom of the held portion <NUM>. An upper end of the shaft portion <NUM> projects upward beyond the flange <NUM>. When the connecting member 51A and the piece member 71A are connected through the biasing member <NUM> of the restoring portion 6A, the shaft portion <NUM> is inserted through an insertion hole <NUM> of the piece member 71A from below to be exposed at an upper side of the piece member 71A. A meshing portion <NUM> with multiple teeth, which is capable of meshing with restricting members <NUM> placed on an upper side of the piece member 71A, is provided on a circumference of an end of the shaft portion <NUM>.

As in the second support member <NUM>, the second support member 55A is attached to the headband <NUM> using the fixing member <NUM> together with the cover <NUM>. The first support member <NUM> holding the connecting member 51A is also attached to the second support member 55A. The second support member 55A includes the extending portion <NUM> and a bent portion 552A bent at an end of the extending portion <NUM> to extend substantially in the right-left direction.

The bent portion 552A includes an arrangement base 553A, on which the operation member <NUM> is placed. As in the arrangement base <NUM>, the arrangement base 553A is in a form of a cylinder projecting upward. The arrangement base 553A includes the hole <NUM> at the center thereof, the pair of guides <NUM> disposed across the hole <NUM>, and the receiver <NUM>.

The arrangement base 553A further includes a projection <NUM> projecting upward from a surface of the arrangement base 553A facing the operation member <NUM>. The hole <NUM> is formed in the projection <NUM>. The pair of guides <NUM> partially cut into the projection <NUM>.

As in the switcher <NUM>, the switcher 7A is configured to switch applying and not applying the restoring force by the restoring portion 6A on the connecting member 51A. As shown in <FIG>, the switcher 7A is constructed in the same manner as the switcher <NUM> except that the piece member 71A and a pair of restricting members <NUM> are provided in place of the piece member <NUM> and the pair of restricting members <NUM>. It should be noted that the switcher of the invention refers to a combination of the switcher 7A and the second support member 55A in the second exemplary embodiment.

As in the piece member <NUM>, the piece member 71A, which is substantially circular as viewed from above, is received in the receiver <NUM> of the second support member 55A in a manner rotatable around the rotation axis AX3. The restoring portion 6A is in the disabled state when the rotation of the piece member 71A is allowed and is in the enabled state when the rotation of the piece member 71A is restricted by the restricting members <NUM>.

The piece member 71A has the same structure as that of the piece member <NUM> except for a boss 711A in place of the boss <NUM>.

In place of the screw hole <NUM>, the boss 711A includes an insertion hole <NUM> penetrating therethrough along the rotation axis AX3. The shaft portion <NUM> is inserted through the insertion hole <NUM>.

The pair of restricting members <NUM> are configured to move in accordance with the movement of the operation member <NUM> to restrict or allow the rotation of the piece member 71A, thereby enabling or disabling the restoring portion 6A. As shown in <FIG>, the pair of restricting members <NUM> are disposed between the piece member 71A and the second support member 55A. As in the restricting members <NUM>, each of the pair of restricting members <NUM> includes the boss <NUM> and the restricting portion <NUM>.

<FIG> is a perspective view showing a positional relationship between the shaft portion <NUM> of the connecting member 51A, the piece member 71A, and the restricting members <NUM>. Specifically, <FIG> is a perspective view showing an interior of the connector 4A when the rotation of the piece member 71A is restricted by the restricting members <NUM> to enable the restoring portion 6A.

Further, each of the pair of restricting members <NUM> includes a locking portion <NUM> at a part facing the meshing portion <NUM> of the connecting member 51A as shown in <FIG>. The locking portion <NUM> includes multiple teeth configured to mesh with the meshing portion <NUM>. When the pair of restricting members <NUM> are moved toward an inside of the piece member 71A (i.e. in a direction toward the meshing portion <NUM>) in response to the rotation of the operation member <NUM>, the locking portion <NUM> meshes with the meshing portion <NUM>. The connecting member 51A (and, consequently, the sound emitter <NUM>) is thus locked to be fixed.

As in the connector <NUM>, when the pair of restricting members <NUM> are fully moved in the +D2 direction (i.e. radially outward from the rotation axis AX3) in response to the rotation of the operation member <NUM> in the +D1 direction around the rotation axis AX3, the restricting portions <NUM> of the respective restricting members <NUM> are received in the corresponding cutouts <NUM> of the piece member 71A as shown in <FIG>. In this state, each of the restricting portions <NUM> are in contact with corresponding one of abutment portions <NUM> to restrict the rotation of the piece member 71A. Accordingly, the biasing force (restoring force) of the biasing member <NUM>, whose extending portion <NUM> is engaged with the piece member 71A, is capable of acting on the connecting member 51A engaged with the extending portion <NUM>. The position of each of the restricting members <NUM> in this state is the restricting position according to the invention.

It should be noted that the hanger <NUM> and the connecting member 51A are, in the same manner as the above, rotatable around the rotation axis AX3 toward the rear side by <NUM> degrees with respect to the reference position at which sound-emitting surfaces <NUM> of the sound emitters <NUM> face each other. The biasing member <NUM> applies the restoring force on the connecting member 51A when the sound-emitting surface <NUM> of the sound emitter <NUM> is rotated in a direction to face the rear side. Accordingly, the sound emitter <NUM> can be easily positioned at the reference position, so that the headphone 1A can be easily maintained in an orientation for a typical user to use the headphone 1A.

<FIG> is a perspective view showing the interior of the connector 4A when the rotation of the piece member 71A is allowed by the restricting members <NUM> to disable the restoring portion 6A.

When the operation member <NUM> is rotated in the -D1 direction (i.e. an opposite direction to the +D1 direction), the bosses <NUM> at an outer part of the operation member <NUM> move toward the inner part of the operation member <NUM> along the guides <NUM>. The restricting members <NUM> are thus moved in the -D2 direction (i.e. an opposite direction to the +D2 direction) as shown in <FIG>, so that the restricting portions <NUM> are located inside the pair of rising portions <NUM> of the piece member 71A. In this state, even when the piece member 71A is rotated together with the connecting member 51A, the abutment portions <NUM> are not in contact with the respective restricting portions <NUM>. Accordingly, the biasing member <NUM> and the piece member 71A are rotated integrally with the connecting member 51A, so that the biasing force (restoring force) of the biasing member <NUM> no more acts on the connecting member 51A. Thus, the connecting member 51A and the sound emitter <NUM> are capable of freely rotating within the rotation range. The position of each of the restricting members <NUM> in this state is the allowing position according to the invention.

<FIG> is a perspective view showing the interior of the connector 4A when the locking portion <NUM> is meshed with the meshing portion <NUM> of the connecting member 51A. Specifically, <FIG> is a perspective view showing the interior of the connector 4A when the connecting member 51A is locked by the locking portion <NUM>.

When the operation member <NUM> is further rotated in the -D1 direction to fully move each of the restricting members <NUM> in the -D2 direction, the locking portion <NUM> of each of the restricting members <NUM> is meshed with the meshing portion <NUM> of the connecting member 51A to lock the connecting member 51A as shown in <FIG>. In this state, since the rotation of the connecting member 51A is, even tried, restricted by the restricting members <NUM>, the position of the connecting member 51A and, consequently, the hanger <NUM> (sound emitter <NUM>) is fixed. The position of each of the restricting members <NUM> in this state is referred to as a fixing position.

It should be noted that the meshing portion <NUM> is continuously formed on a circumferential surface of the shaft portion <NUM> held by the pair of restricting members <NUM> (i.e. over an entire circumference of the shaft portion <NUM>), and the connecting member 51A is freely rotatable within the rotation range until being locked by the locking portion <NUM>. Accordingly, the connecting member 51A and, consequently, the sound emitter <NUM> can be fixed at a desired angle by meshing the locking portions <NUM> of the restricting members <NUM> with the meshing portion <NUM> while the connecting member 51A is rotated by the desired angle (predetermined rotation angle).

The headphone 1A according to the second exemplary embodiment as described above can achieve not only the same advantages as those of the headphone <NUM> but also the following advantages.

When the operation member <NUM> is fully rotated in the -D1 direction, the pair of restricting members <NUM> hold and lock the connecting member 51A. Specifically, the locking portion <NUM> of each of the restricting members <NUM> is meshed with the meshing portion <NUM> to lock and fix the connecting member 51A and, consequently, the sound emitter <NUM>. The sound emitter <NUM> can thus be kept rotated at an angle desired by the user. The user-friendliness of the headphone 1A can thus be improved.

Further, since the locking portion <NUM> of each of the restricting members <NUM> meshes with the meshing portion <NUM> of the connecting member 51A, the rotation of the connecting member 51A can be reliably restricted as compared with the restricting member <NUM> simply holding the shaft portion <NUM>. In addition, since it is not necessary for the restricting members <NUM> to continuously apply the pushing force on the shaft portion <NUM>, the load applied on the restricting members <NUM> can be reduced.

Though not shown in the drawings, the operation member <NUM> may be configured so that the position thereof is fixed or temporarily fixed when the restricting members <NUM> are located at at least one of the restricting position, the allowing position, and the fixing position.

For instance, a projection may be provided on one of the operation member <NUM> and the arrangement base 553A and at least one recess for receiving the projection may be provided on the other of the operation member <NUM> and the arrangement base 553A at a position corresponding to the position of the projection when the restricting members <NUM> are located at at least one of the restricting position, the allowing position, and the fixing position.

With the connector 4A configured as described above, the user can easily recognize how and/or whether the connecting member 51A and the sound emitter <NUM> are restricted by the operation member <NUM>, and unexpected rotation of the operation member <NUM>, which could change the restricted condition of the connecting member 51A and the sound emitter <NUM>, can be restrained.

Next, a third exemplary embodiment of the invention will be described.

A headphone according to the third exemplary embodiment is structurally the same as the headphone <NUM> except that the headphone of the third exemplary embodiment is further configured to reduce the load applied on the restricting members <NUM>. It should be noted that the same or substantially the same parts as already described will be denoted by the same reference characters hereinbelow for omission of the description thereof.

<FIG> is an exploded perspective view showing a structure of a connector 4B of a headphone 1B according to the third exemplary embodiment.

The headphone 1B according to the third exemplary embodiment is structurally and functionally the same as the headphone <NUM> except for a pair of connectors 4B, which are provided in place of the pair of connectors <NUM>.

Each of the connectors 4B is provided to corresponding one of the right and left ends of the headband <NUM> in the same manner as the connectors <NUM> and are configured to support corresponding one of the sound emitters <NUM> (hangers <NUM>) so that the sound emitters <NUM> are rotatable around the rotation axis AX3 along the top-bottom direction, thereby connecting the headband <NUM> and the sound emitters <NUM>. As shown in <FIG>, each of the connectors 4B includes a support <NUM>, the restoring portion <NUM>, and a switcher <NUM>.

It should be noted that the connector 4B located on the left side and the connector 4B located on the right side with respect to the headband <NUM> are symmetrically arranged but of the same structure in other respects. Accordingly, the connector 4B located on the left side will be described and the description on the connector 4B located on the right side will be omitted hereinbelow.

As in the support <NUM>, the support <NUM> is attached to the headband <NUM> with the hanger <NUM> being connected, thereby supporting the hanger <NUM> so that the hanger <NUM> is rotatable. The support <NUM> includes a connecting member <NUM>, a first support member <NUM>, a cover <NUM>, a fixing member <NUM> and a second support member <NUM>.

As in the connecting members <NUM> and 51A, the connecting member <NUM> is connected to the second connecting portion <NUM> so that the hanger <NUM> is rotatable around the rotation axis AX2 (see <FIG>) along the front-back direction. The connecting member <NUM> includes the barrel portion <NUM> at a lower part and a held portion <NUM> at an upper part.

The held portion <NUM> includes an annular flange <NUM> extending radially outward from the circumference of the held portion <NUM> to be supported by the first support member <NUM>, and projections <NUM> to <NUM> and a recess <NUM> provided on the flange <NUM>.

The projection <NUM> projects downward from a part of the flange <NUM>.

The projections <NUM> to <NUM> project from an upper side of the flange <NUM>. Among the above, the projection <NUM> defines a post for the piece member <NUM> to be placed thereon. The projection <NUM> is configured to be in contact with one and the other of two protrusions <NUM>, <NUM> (see <FIG>) provided on the second support member <NUM> when the connecting member <NUM> is rotated together with the hanger <NUM>, thereby delimiting the rotation range of the connecting member <NUM>. The projection <NUM>, <NUM> are located relatively close to each other at positions opposite the projection <NUM> across the center axis of the connecting member <NUM>. A cable connected with the sound-emitting unit <NUM> of the sound emitter <NUM> is disposed between the projections <NUM>, <NUM>.

The extending portion <NUM> of the biasing member <NUM> is inserted into the recess <NUM>. The biasing force (restoring force) of the biasing member <NUM> acts on the connecting member <NUM> via the extending portion <NUM>.

As in the first support member <NUM>, the first support member <NUM> includes a first holder piece <NUM> and a second holder piece <NUM>. The holder pieces <NUM>, <NUM> are combined via a pair of fixing members <NUM>, which are inserted along a right-left direction and fixed to the second support member <NUM>.

When the headphone 1B is worn by a user, the first holder piece <NUM> is located at a side facing the user and the second holder piece <NUM> is located at a side opposite the user. The first holder piece <NUM> and the second holder piece <NUM> include semi-circular open portions <NUM>, <NUM>, respectively, in which a part of the held portion <NUM> below the flange <NUM> is fitted. In addition, the first holder piece <NUM> includes a recess <NUM> formed along the open portion <NUM>. The second holder piece <NUM> includes a recess <NUM> formed along the open portion <NUM>. When the first holder piece <NUM> and the second holder piece <NUM> are combined, the held portion <NUM> of the connecting member <NUM> is held by the first holder piece <NUM> and the second holder piece <NUM> from right and left sides. At this time, a part of the flange <NUM> near the first holder piece <NUM> is received within the recess <NUM> and a part of the flange <NUM> near the second holder piece <NUM> is received within the recess <NUM>. The connecting member <NUM> is thus rotatably supported by the first support member <NUM>.

As in the cover <NUM>, the cover <NUM> fixes the second support member <NUM> (extending portion <NUM>) to an end of the headband <NUM>. The fixing member <NUM> (e.g. a screw) penetrating through the cover <NUM> and the headband <NUM> is fixed to the second support member <NUM>, thereby fixing the cover <NUM> and the second support member <NUM> to the end of the headband <NUM>.

Though not illustrated, the cover <NUM> also has holes for receiving the fixing members <NUM>.

As in the second support members <NUM> and 55A, the second support member <NUM> is attached to the end of the headband <NUM>. The first support member <NUM> holding the connecting member <NUM> is attached to the second support member <NUM>. As in the second support member <NUM>, the second support member <NUM> includes the extending portion <NUM> and a bent portion <NUM>.

An arrangement base <NUM>, which is provided on the bent portion <NUM>, includes a hole <NUM> and a pair of guides <NUM> as in the arrangement base <NUM>. In addition, the arrangement base <NUM> includes a pair of defining portions <NUM> projecting at positions symmetric with respect to the hole <NUM>, the defining portions <NUM> delimiting the rotation range of the operation member <NUM>.

<FIG> is a perspective view showing the second support member <NUM> (bent portion <NUM>) from below.

As shown in <FIG>, the second support member <NUM> includes screw holes <NUM>, <NUM>, and two protrusions <NUM>, <NUM> as well as a receiver <NUM>, which is recessed in the same manner as the receiver <NUM> on a surface opposite the arrangement base <NUM> (i.e. a surface facing the first support member <NUM>).

The number of the screw holes <NUM>, in which each of the fixing members <NUM> is fixed, is two in the third exemplary embodiment.

The number of the screw holes <NUM>, through which the pair of fixing members <NUM> having penetrated through the holder pieces <NUM>, <NUM> of the first support member <NUM> are fixed, is two in the third exemplary embodiment.

The protrusions <NUM>, <NUM> are disposed so that an imaginary line VL1 connecting the protrusions <NUM>, <NUM> intersects an imaginary line VL2 connecting the pair of guides <NUM>. Further, the protrusions <NUM>, <NUM> are disposed to be located outside the piece member <NUM> of the switcher <NUM> when the second support member <NUM> is combined with the switcher <NUM>. The projection <NUM> is located between the protrusions <NUM>, <NUM>.

When the sound emitter <NUM> is rotated in a first direction, the projection <NUM> is in contact with one of the protrusions <NUM>, <NUM> at a first terminal end of the rotation range of the sound emitter <NUM>.

When the sound emitter <NUM> is rotated in a second direction, the projection <NUM> is in contact with the other of the protrusions <NUM>, <NUM> at a second terminal end of the rotation range of the sound emitter <NUM>.

Thus, the rotation range of the sound emitter <NUM> is defined by the positions for the projection <NUM> to be in contact with one and the other of the protrusions. When the projection <NUM> is in contact with one of the protrusions, the sound emitter <NUM> is located at the reference position and, when the projection <NUM> is in contact with the other of the protrusions, the sound emitter <NUM> is oriented so that the sound-emitting surface <NUM> faces the rear side in the third exemplary embodiment.

As in the switchers <NUM>, 7A, the switcher <NUM> is configured to switch the enabled state in which the restoring portion <NUM> is enabled to allow the restoring force to act on the connecting member <NUM> (and consequently on the hanger <NUM>) and the disabled state in which the restoring portion <NUM> is disabled to keep the restoring force from acting on the connecting member <NUM>. As shown in <FIG>, the switcher <NUM> includes the piece member <NUM>, the operation member <NUM>, a pair of restricting members <NUM>, and an intermediate member <NUM>. It should be noted that the switcher of the invention is also defined by a combination of the switcher <NUM> and the second support member <NUM> in the third exemplary embodiment.

Among the above, the operation member <NUM> is located above the second support member <NUM>, and the pair of restricting members <NUM>, the intermediate member <NUM>, and the piece member <NUM> are located below the second support member <NUM>.

As in the operation member <NUM>, the operation member <NUM>, which is attached to the arrangement base <NUM> in a manner rotatable around the rotation axis AX3, is a drive member for moving the pair of restricting members <NUM>. Specifically, the operation member <NUM> that is in a form of a dial is configured to, in response to a rotary movement applied by a user, move the pair of restricting members <NUM> in an orthogonal direction orthogonal to the rotation axis AX3 (i.e. in a radial direction of the piece member <NUM>) and rotate the intermediate member <NUM> in the same direction as the rotation of the operation member <NUM> to cause the movement of the pair of restricting members <NUM> in the orthogonal direction.

The operation member <NUM> includes a knob <NUM> projecting from an outer circumferential surface of the operation member <NUM> and configured to be operated by a user. In addition, though not illustrated in detail, the operation member <NUM> includes a projection <NUM> projecting from the center of a bottom side to be inserted into the later-detailed intermediate member <NUM>, and the pair of guide grooves <NUM> symmetrical with respect to the projection <NUM>.

<FIG> is a perspective view showing a positional relationship between the piece member <NUM>, the pair of restricting members <NUM>, and the intermediate member <NUM>. <FIG> illustrates the pair of restricting members <NUM> and the intermediate member <NUM> as viewed from above. It should be noted that the restricting members <NUM> are disposed inside the rising portions <NUM> in <FIG> and <FIG>.

As in the pair of restricting members <NUM>, the pair of restricting members <NUM> move in the radial directions of the piece member <NUM> in response to the rotation of the operation member <NUM>, restricting the rotation of the piece member <NUM>. As shown in <FIG> and <FIG>, each of the restricting members <NUM> is an integrated component including a boss <NUM>, a restricting portion <NUM>, and a curved portion <NUM>.

The boss <NUM> corresponds to the engagement portion of the invention. Each of the bosses <NUM> is inserted through corresponding one of the guides <NUM> of the second support member <NUM> to be received in the corresponding one of the guide grooves <NUM> of the operation member <NUM>.

The restricting portions <NUM>, which are each provided under the corresponding boss <NUM>, are moved toward an inside and outside of the cutouts <NUM> together with the movement of the restricting members <NUM>.

The curved portion <NUM> is a part of each of the restricting portions <NUM> facing corresponding one of push portions <NUM> of the intermediate member <NUM>, which is located between the restricting members <NUM>. The curved portion <NUM> has a curved profile conforming to the profile of corresponding one of the push portions <NUM> and is configured to be pushed by the corresponding one of the push portions <NUM> in accordance with the rotation of the intermediate member <NUM>. Each of the restricting members <NUM>, whose boss <NUM> is engaged with the operation member <NUM>, is thus moved in the +D2 direction in accordance with the rotation of the operation member <NUM> in the +D1 direction, and also moved in the +D2 direction by the pushing force applied by the intermediate member <NUM>.

The intermediate member <NUM> is configured to be rotated integrally with the operation member <NUM> to move the restricting members <NUM> in the +D2 direction (i.e. outward in the radial direction). As shown in <FIG> and <FIG>, the intermediate member <NUM> includes a cylindrical portion <NUM>, a hole <NUM>, two push portions <NUM>, a flange <NUM>, two cutouts <NUM>, and two projections <NUM>.

The cylindrical portion <NUM>, which define an upper part of the intermediate member <NUM>, is in a form of a substantially elliptical cylinder. The cylindrical portion <NUM> is located at a position to be held by the restricting members <NUM>.

The hole <NUM> is provided on an upper side of the cylindrical portion <NUM>. The projection <NUM> (see <FIG>) of the operation member <NUM> is inserted into the hole <NUM>, thereby integrally attaching the intermediate member <NUM> with the operation member <NUM>.

Each of the two push portions <NUM>, which are defined by curves at parts of lateral face of the cylindrical portion <NUM> facing the respective restricting members <NUM>, is configured to push the curved portion <NUM> of each of the restricting members <NUM>. The curved profile of each of the push portions <NUM> is designed so that the movement of each of the restricting members <NUM> caused by the push portions <NUM> is synchronized with (i.e. in the same moving speed and movement direction as) the movement of the restricting members <NUM> along the corresponding guide grooves <NUM> in accordance with the rotation of the operation member <NUM>.

The flange <NUM>, which define a lower part of the intermediate member <NUM>, is in a form of a circle having an outer diameter larger than the cylindrical portion <NUM>. The flange <NUM> is interposed between the upper side <NUM> of the piece member <NUM> and the restricting members <NUM>.

The cutouts <NUM> divide the flange <NUM> into two parts. The projections <NUM> are provided on respective ends of the divided parts of the flange <NUM>.

<FIG> illustrates the rotated states of the restricting members <NUM> and the intermediate member <NUM> when the operation member <NUM> is rotated in the +D1 direction as viewed from above.

When the operation member <NUM> is rotated in the +D1 direction from the state where the restricting members <NUM> are located inside the rising portions <NUM> as shown in <FIG> and <FIG>, the bosses <NUM> received in the respective guide grooves <NUM> of the operation member <NUM> are moved in the +D2 direction along the guides <NUM> of the second support member <NUM>, as shown in <FIG>. Together with the movement of the bosses <NUM>, the intermediate member <NUM> is rotated in the +D1 integrally with the operation member <NUM> to cause the push portions <NUM> to push the respective curved portions <NUM> and move the restricting portions <NUM> in the +D2 direction.

As described above, the shapes of the guide grooves <NUM>, the curved portions <NUM>, and the push portions <NUM> are designed so that the moving speed of the bosses <NUM> in the +D2 direction becomes substantially the same as the moving speed of the restricting portions <NUM> in the +D2 direction. Thus, the restricting members <NUM> is restrained from inclining with respect to the +D2 direction and a large load is restrained from being applied on the bosses <NUM>.

<FIG> shows the rotated states of the restricting members <NUM> and the intermediate member <NUM> when the operation member <NUM> is fully rotated in the +D1 direction as viewed from above. <FIG> is a perspective view showing the positions of the restricting members <NUM> and the intermediate member <NUM> as shown in <FIG> with respect to the piece member <NUM>.

When the operation member <NUM> is fully rotated in the +D1 direction from the rotated state as shown in <FIG>, the restricting members <NUM> are further moved in the +D2 direction to reach the terminal end of the movement range of the restricting members <NUM> as shown in <FIG>. At this time, the restricting portions <NUM> of the restricting members <NUM> are received in the cutouts <NUM> as shown in <FIG>, thereby allowing the restricting portions <NUM> to be in contact with the respective abutment portions <NUM>. The rotation of the piece member <NUM> around the rotation axis AX3 is thus restricted, and the state of the restoring portion <NUM> is switched to the enabled state where the biasing force (restoring force) of the biasing member <NUM> is capable of acting on the connecting member <NUM> as in the connectors <NUM>, 4A.

Meanwhile, when the operation member <NUM> is rotated in an opposite direction to the +D1 direction from the state shown in <FIG> and <FIG>, the restricting members <NUM> move in an opposite direction to the +D2 direction along the guide grooves <NUM> of the operation member <NUM>, so that the restricting members <NUM> are located inside the pair of rising portions <NUM> as shown in <FIG>. The restriction on the rotation of the piece member <NUM> is thus cancelled to allow the rotation of the piece member <NUM> together with the connecting member <NUM>, thereby switching the state of the restoring portion <NUM> to the disabled state where the biasing force (restoring force) of the biasing member <NUM> is incapable of acting on the connecting member <NUM>.

Without the intermediate member <NUM>, the following problem could occur.

The restricting members <NUM> are movable so that the restricting portions <NUM> are received in the respective cutouts <NUM>, as long as the cutouts <NUM> of the piece member <NUM> are located in the +D2 direction when the restricting members <NUM> are moved in the +D2 direction. However, if the cutouts <NUM> are not located in the +D2 direction as a result of the rotation of the piece member <NUM> together with the connecting member <NUM>, the restricting portions <NUM> would be in contact with the inner sides of the rising portions <NUM> even when the operation member <NUM> is rotated, thereby restricting the movement of the restricting members <NUM> in the +D2 direction.

If the operation member <NUM> is further rotated while the movement of the restricting members <NUM> in the +D2 direction is restricted by the rising portions <NUM> as described above, the pushing force for urging the restricting members <NUM> in the +D2 direction would be applied solely on the bosses <NUM>. Thus, when the bosses <NUM> are not rigid enough, the bosses <NUM> might be deformed or damaged.

In contrast, the push portion <NUM> of the intermediate member <NUM> in the third exemplary embodiment urges the restricting members <NUM> to move at substantially the same moving speed as the moving speed of the restricting members <NUM> caused by the guide grooves <NUM> of the operation member <NUM> in response to the rotation of the operation member <NUM>. The pushing force caused by the rotation of the operation member <NUM> thus acts on the boss <NUM> and the curved portion <NUM> (restricting portion <NUM>) of each of the restricting members <NUM>. The pushing force acting on the restricting members <NUM> is thus distributed to the respective parts. Accordingly, the connector 4B, which is complicated in structure than the connector <NUM> due to the additional intermediate member <NUM>, can reduce deformation and/or damage on the restricting members <NUM>.

The headphone 1B according to the third exemplary embodiment as described above can achieve not only the same advantages as those of the headphone <NUM> but also the following advantages.

The switcher <NUM> includes the intermediate member <NUM> rotatable in accordance with the operation member <NUM> in a form of a dial. The intermediate member <NUM> includes the push portions <NUM> configured to push the restricting members <NUM> in a direction for the restricting members <NUM> to be moved in accordance with the rotation of the operation member <NUM>. With the above arrangement, even when the operation member <NUM> is further moved in the +D1 direction while the cutouts <NUM> are not present in the +D2 direction, the load applied on the bosses <NUM> can be reduced as described above. Accordingly, the deformation and/or damage of the restricting members <NUM> can be reduced, so that the enabled state and the disabled state of the restoring portion <NUM> can be reliably switched.

The push portions <NUM> each have a curved profile as viewed along the rotation axis of the intermediate member <NUM> (coaxial with the rotation axis AX3) so that the moving speed of the respective restricting members <NUM> in the +D2 direction in accordance with the rotation of the operation member <NUM> becomes equal to the moving speed of the respective restricting members <NUM> in the +D2 direction by the intermediate member <NUM>. The pushing force applied on the bosses <NUM> by the guide grooves <NUM> of the operation member <NUM> can thus be equalized with the pushing force applied to the curved portions <NUM> by the intermediate member <NUM>, thereby reliably distributing the pushing force acting on the restricting member <NUM>. Accordingly, the deformation and/or damage on the restricting members <NUM> can be reliably reduced.

Next, a fourth exemplary embodiment of the invention will be described.

A headphone according to the fourth exemplary embodiment is structurally the same as the headphone 1B except that the restricting member is provided between the second support member and the operation member. It should be noted that the same or substantially the same parts as already described will be denoted by the same reference characters hereinbelow for omission of the description thereof.

<FIG> is an exploded perspective view showing a structure of a connector 4C of a headphone 1C according to the fourth exemplary embodiment.

The headphone 1C according to the fourth exemplary embodiment is structurally and functionally the same as the headphone 1B except for a pair of connectors 4C, which are provided in place of the pair of connectors 4B.

Each of the connectors 4C is provided to corresponding one of the right and left ends of the headband <NUM> in the same manner as the connectors <NUM>, 4A, 4B and are configured to support corresponding one of the sound emitters <NUM> (hangers <NUM>) so that the sound emitters <NUM> are rotatable around the rotation axis AX3 along the top-bottom direction, thereby connecting the headband <NUM> and the sound emitters <NUM>. As shown in <FIG>, each of the connectors 4C includes a support 8C, the restoring portion <NUM>, and a switcher 9C.

It should be noted that the connector 4C located on the left side and the connector 4C located on the right side with respect to the headband <NUM> are symmetrically arranged but of the same structure in other respects. Accordingly, the connector 4C located on the left side will be described and the description on the connector 4C located on the right side will be omitted hereinbelow.

As in the supports <NUM>, 5A and <NUM>, the support 8C is attached to the headband <NUM> with the hanger <NUM> being connected, thereby supporting the hanger <NUM> and, consequently, the sound emitter <NUM> so that the hanger <NUM> and the sound emitter <NUM> are rotatable. The support 8C is structurally and functionally the same as the support <NUM> except that the support 8C includes a second support member <NUM> in place of the second support member <NUM>.

<FIG> is a perspective view showing the second support member <NUM> as viewed from above. Specifically, <FIG> is a perspective view showing the second support member <NUM> combined with the piece member <NUM> as viewed from above.

As in the second support members <NUM>, 55A and <NUM>, the second support member <NUM> is attached to an end of the headband <NUM>. The first support member <NUM> holding the connecting member <NUM> is attached to the second support member <NUM>. As shown in <FIG> and <FIG>, the second support member <NUM> includes the extending portion <NUM> and a bent portion <NUM> bent at an end of the extending portion <NUM> to extend substantially in the right-left direction.

The bent portion <NUM> includes an arrangement base <NUM>, on which an operation member 91C (described later) is placed. The arrangement base <NUM> is a two-stage cylindrical upward projection of a profile corresponding to an outer profile of the operation member 91C. Thus, a step portion <NUM> is formed along a periphery of the arrangement base <NUM>. The step portion <NUM> is covered with the operation member 91C.

In addition, the arrangement base <NUM> includes a guide <NUM>, an insertion hole <NUM>, a pair of cuts <NUM>, a pair of holes <NUM>, and a pair of protrusions <NUM> as shown in <FIG>.

The guide <NUM> is a substantially rectangular recess extending diametrically in the arrangement base <NUM> as viewed from above. The insertion hole <NUM> is provided at the bottom of the guide <NUM> at a position corresponding to the center of the arrangement base <NUM>. The restricting members <NUM> are received in the guide <NUM>. In addition, a projection <NUM> and push portions <NUM> of the operation member 91C (see <FIG> and <FIG>) are disposed in the guide <NUM> when the operation member 91C is placed on the arrangement base <NUM>. In other words, the guide <NUM> is configured to guide a linear movement of the restricting members <NUM> in accordance with the rotation of the operation member 91C.

The pair of cuts <NUM> are formed in respective longitudinal ends of the guide <NUM>. The rising portions <NUM> and the cutouts <NUM> of the piece member <NUM> combined with the second support member <NUM> are exposed through the pair of cuts <NUM>.

The pair of holes <NUM> are formed outside the guide <NUM> across the insertion hole <NUM>. Each of the pair of holes <NUM> vertically penetrates through the second support member <NUM>. A later-described ball <NUM> is received in each of the holes <NUM>.

The pair of protrusions <NUM> are formed near an outer periphery with respect to the pair of holes <NUM> across the insertion hole <NUM>. The pair of protrusions <NUM> are formed so that an imaginary line (not shown) connecting the protrusions <NUM> and an imaginary line (not shown) connecting the pair of holes <NUM> intersect each other. The protrusions <NUM> are received in respective restricting grooves <NUM> (see <FIG> and <FIG>) of the operation member 91C placed on the arrangement base <NUM> to define a rotation range of the operation member 91C.

In addition, the bent portion <NUM> is provided with a receiver <NUM> in a form of a recess on a surface opposite the arrangement base <NUM> (i.e. the surface facing the first support member <NUM>) as shown in <FIG>, as well as the screw holes <NUM>, <NUM> and the protrusions <NUM>, <NUM> (not shown).

As in the switchers <NUM>, 7A and <NUM>, the switcher 9C is configured to switch the enabled state in which the restoring portion <NUM> is enabled to allow the restoring force to act on the connecting member <NUM> (and consequently on the sound emitter <NUM>) and the disabled state in which the restoring portion <NUM> is disabled to keep the restoring force from acting on the connecting member <NUM>. As shown in <FIG>, the switcher 9C includes the operation member 91C, an intermediate member <NUM>, an O-ring <NUM>, a fixing member <NUM>, biasing members <NUM>, and the balls <NUM> as well as the above-described piece member <NUM> and the pair of restricting members <NUM> as shown in <FIG>.

The fixing member <NUM> in the fourth exemplary embodiment is a screw. The pair of restricting members <NUM> are received in the guide <NUM> across the rotation axis of the piece member <NUM> (coaxial with the rotation axis AX3), as described above.

<FIG> and <FIG> are a perspective view and a bottom view, respectively, showing the operation member 91C from below. It should be noted that one of the pair of restricting grooves <NUM> and two of the four holes <NUM> of the operation member 91C are shown in <FIG> for the convenience of illustration.

As in the operation member <NUM>, the operation member 91C, which is attached to the arrangement base <NUM> in a manner rotatable around the rotation axis AX3, is a drive member in a form of a dial for moving the pair of restricting members <NUM> in the fourth exemplary embodiment. As shown in <FIG> and <FIG>, the operation member 91C has a bottomed cylindrical shape placed upside down. The operation member 91C includes the laterally-projecting knob <NUM>, a boss <NUM>, a screw hole <NUM>, the projection <NUM>, the pair of push portions <NUM>, a pair of guide grooves <NUM>, the pair of restricting grooves <NUM>, and the four holes <NUM>.

The boss <NUM> is a substantially cylindrical component projecting at a center of an inner surface 91CA defining the bottom of the bottomed cylindrical shape of the operation member 91C. When the operation member 91C is placed on the arrangement base <NUM>, the boss <NUM> penetrates through the insertion hole <NUM> to be exposed at a lower side of the second support member <NUM>.

The screw hole <NUM> is formed at an end surface (bottom side) of the boss <NUM>. The fixing member <NUM> for fixing the later-described intermediate member <NUM> to the boss <NUM> is secured to the screw hole <NUM>.

The projection <NUM>, which is a substantially elliptical cylinder projecting from a lateral surface of the boss <NUM>, is received in the guide <NUM> of the arrangement base <NUM>.

The pair of push portions <NUM>, which are defined at parts of the projection <NUM> opposite each other, are configured to push and move the pair of restricting members <NUM> (also received in the guide <NUM>) in mutually separating directions when the operation member 91C is rotated. As in the push portions <NUM> of the intermediate member <NUM>, the pair of push portions <NUM> each have a curved profile. Specifically, the push portions <NUM> are defined by curved surfaces so that the moving speed of the restricting members <NUM> in a certain direction caused by the later-described guide groove <NUM> in accordance with the rotation of the operation member 91C becomes substantially equal to the moving speed of the restricting members <NUM> in the certain direction being pushed by the pair of push portions <NUM>.

Specifically speaking, the push portions <NUM>, which are each defined by an arc as a whole, are each divided into a first pushing portion <NUM> and a second pushing portion <NUM> substantially at a half in a circumferential direction of each of the push portions <NUM>. Though not illustrated, the center of curvature of the first pushing portion <NUM> is located at the center of the screw hole <NUM>, whereas the center of curvature of the second pushing portion <NUM> is offset from the center of the screw hole <NUM>. The curved portion <NUM> of each of the restricting members <NUM> of the fourth exemplary embodiment is curved in conformity with the profile of the corresponding one of the push portions <NUM>.

The pair of guide grooves <NUM> are arc-shaped grooves formed in the inner surface 91CA across the boss <NUM>. As in the pair of guide grooves <NUM>, the boss <NUM> of corresponding one of the restricting members <NUM> is inserted into each of the pair of guide grooves <NUM>. The restricting members <NUM> are thus moved in directions toward and away from each other in accordance with the rotation of the operation member 91C.

The pair of restricting grooves <NUM>, which are formed at an outer periphery of the inner surface 91CA, are arc-shaped grooves around the screw hole <NUM>. An angle of the arc of one of the pair of the restricting grooves <NUM> is the same as an angle of the arc of the other one of the pair of the restricting grooves <NUM>. Each of the protrusions <NUM> is received in corresponding one of the pair of restricting groove <NUM> when the operation member 91C is placed on the arrangement base <NUM>, thereby delimiting the rotation range of the operation member 91C.

Four holes <NUM> (919A, 919B) are formed in the inner surface 91CA. Two of the four holes 919A are provided on a first imaginary line (not illustrated) passing through the center of the screw hole <NUM>, whereas the other two of the holes 919B are provided on a second imaginary line passing through the center of the screw hole <NUM> and intersecting the first imaginary line at a predetermined intersection angle (approximately <NUM> degrees in the fourth exemplary embodiment). The balls <NUM> provided to the intermediate member <NUM> are fittable in the holes <NUM>.

As shown in <FIG>, the intermediate member <NUM> is disposed inside the pair of rising portions <NUM> of the piece member <NUM>. The fixing member <NUM> having passed through the O-ring <NUM> is inserted into the intermediate member <NUM> to be fixed in the screw hole <NUM> exposed at a lower side through the insertion hole <NUM>. The intermediate member <NUM> is thus integrated with the operation member 91C with the second support member <NUM> interposed therebetween. In other words, the second support member <NUM> and the pair of restricting members <NUM> are held by the intermediate member <NUM> and the operation member 91C to keep the pair of restricting members <NUM> from dropping off.

The intermediate member <NUM> includes a first intermediate member <NUM> and a second intermediate member <NUM>.

The first intermediate member <NUM>, which is a support member for supporting the biasing members <NUM> and the balls <NUM>, is combined with the second intermediate member <NUM> fixed to the screw hole <NUM> (i.e. to the operation member 91C). The first intermediate member <NUM> includes an annular body <NUM> defining a circular opening <NUM>, a pair of pins <NUM> projecting from an upper side of the body <NUM>, and a recess <NUM>.

An insertion portion <NUM> of the second intermediate member <NUM> is inserted into the opening <NUM>. Accordingly, the first intermediate member <NUM> is not rotated even when the second intermediate member <NUM> is rotated integrally with the operation member 91C.

The pair of pins <NUM> project across the opening <NUM>. The biasing member <NUM> in a form of a compression coil spring is provided at an end of each of the pair of pins <NUM>. The balls <NUM> are each provided at an end of the biasing member <NUM>. The balls <NUM> are exposed from an upper side of the arrangement base <NUM> through the respective holes <NUM>. When the balls <NUM> are fitted into the holes <NUM> in accordance with the rotated state of the operation member 91C placed on the arrangement base <NUM>, a user senses a clicking touch each time the operation member 91C is rotated. The pins <NUM> are disposed so that a direction connecting the pins <NUM> approximately orthogonally intersects a direction for the pair of restricting members <NUM> to face each other.

The recess <NUM> is at a bottom side of the first intermediate member <NUM>. A body <NUM> of the second intermediate member <NUM> is fitted into the recess <NUM>.

The second intermediate member <NUM> is a component for attaching the first intermediate member <NUM> to the operation member 91C. The second intermediate member <NUM> includes the body <NUM>, the insertion portion <NUM>, a through hole <NUM>, holders <NUM> and a recess <NUM>.

The body <NUM>, which defines an outer periphery of the second intermediate member <NUM>, is a substantially disc-shaped component. The body <NUM> is fitted into the recess <NUM>.

The insertion portion <NUM> is a substantially cylindrical component projecting from an upper side of the body <NUM>. The insertion portion <NUM> is inserted into the opening <NUM> of the first intermediate member <NUM>.

The through hole <NUM> vertically penetrates through the body <NUM> and the insertion portion <NUM> along the top-bottom direction. The fixing member <NUM> is inserted into the through hole <NUM> from below.

The holders <NUM>, which are provided in a pair on an upper side of the insertion portion <NUM> across the through hole <NUM>, hold the fixing member <NUM> inserted through the through hole <NUM>. Mutually facing surfaces of the holders <NUM> are threaded to be meshed with the fixing member <NUM> in a form of a screw.

The recess <NUM> is provided on a lower side of the body <NUM>. The O-ring <NUM> and a head of the fixing member <NUM> (screw) are received in the recess <NUM>.

<FIG> is a perspective view as viewed from above showing positions of the pair of restricting members <NUM> when the restoring portion <NUM> is disabled. It should be noted that the operation member 91C is not illustrated in <FIG> for the convenience of easily understanding the moving state of the restricting members <NUM>.

When the restoring portion <NUM> is disabled, in other words, when the restoring force of the restoring portion <NUM> does not act on the connecting member <NUM>, the pair of restricting members <NUM> are located near the center of the guide <NUM> of the second support member <NUM> as shown in <FIG>. Specifically, the pair of restricting members <NUM> are located near the center of the guide <NUM> (allowing position) with respect to the pair of cuts <NUM> at both longitudinal ends of the guide <NUM>. Thus, even when the piece member <NUM> whose rising portions <NUM> and the cutouts <NUM> are exposed through the pair of cuts <NUM> is rotated, the restricting members <NUM> are not in contact with the respective abutment portions <NUM>, so that the rotation of the piece member <NUM> is not restricted. In this state, since the piece member <NUM> and the restoring portion <NUM> are rotated together with the connecting member <NUM> and the sound emitter <NUM>, the restoring force by the restoring portion <NUM> is not generated. Thus, irrespective of the rotation of the connecting member <NUM> and the sound emitter <NUM>, the restoring force (the biasing force of the biasing member <NUM>) does not act on the connecting member <NUM> and the sound emitter <NUM>.

<FIG> is a perspective view as viewed from above showing positions of the restricting members <NUM> when the restoring portion <NUM> is enabled. It should be noted that the operation member 91C is also not illustrated in <FIG> for the convenience of easily understanding the moving state of the restricting members <NUM>.

When the operation member 91C is rotated in the +D1 direction from the state (disabled state) shown in <FIG>, the restricting members <NUM> are moved toward the ends of the guide <NUM> (in the +D2 direction) (restricting position) being guided by the guide groove <NUM> with the bosses <NUM> being received therein. At this time, the push portions <NUM> located in the guide <NUM> push the curved portion <NUM> of the respective restricting members <NUM>, so that the restricting members <NUM> are also moved toward the ends of the guide <NUM> (in the +D2 direction). The restricting members <NUM> are thus located at the ends of the guide <NUM> to enable the restoring portion <NUM> as shown in <FIG>.

In this enabled state, since the restricting members <NUM> are located at the respective cutouts <NUM> of the piece member <NUM> exposed through the cuts <NUM>, the rotation of the piece member <NUM> is, even tried, restricted by the restricting portions <NUM> that are in contact with the respective abutment portions <NUM>. Since the piece member <NUM> and the restoring portion <NUM> are unable to rotate together with the connecting member <NUM> and the sound emitter <NUM>, the restoring force by the restoring portion <NUM> is generated when the connecting member <NUM> and the sound emitter <NUM> are rotated. Thus, the restoring force (the biasing force of the biasing member <NUM>) acts on the connecting member <NUM> and the sound emitter <NUM> in a direction for urging the sound emitter <NUM> toward the reference position.

In the enabled state, the protrusions <NUM> of the arrangement base <NUM>, which are each located at an end of corresponding one of the restricting grooves <NUM>, restrict the further rotation of the operation member 91C. Further, the balls <NUM> are fitted in the holes 919B of the operation member 91C to cause the clicking touch in the enabled state. The user can thus easily understand that the operation member 91C is rotated to one of the ends of the rotation range.

When the operation member 91C is rotated in the -D1 direction from the enabled state shown in <FIG>, the restricting members <NUM> are moved by the guide groove <NUM> in the -D2 direction to reach the allowing position. The restoring portion <NUM> is thus disabled as shown in <FIG>.

In the disabled state, the protrusions <NUM> are located at the other ends of the corresponding restricting grooves <NUM> to restrict the further rotation of the operation member 91C and, in addition, the balls <NUM> are fitted in the respective holes 919A to cause the clicking touch. The user can thus easily understand that the operation member 91C is rotated to the end of the rotation range.

The headphone 1C according to the fourth exemplary embodiment as described above can achieve not only the same advantages as those of the headphone 1B but also the following advantage.

In the fourth exemplary embodiment, the operation member 91C (dial) includes the push portions <NUM> configured to push and move the restricting members <NUM> in the +D2 direction when the operation member 91C is rotated in the +D1 direction. The thickness of the projection <NUM>, on which the push portions <NUM> are provided, can thus be increased, so that the strength of the component for pushing and moving the restricting members <NUM> can be enhanced. Accordingly, the operation member 91C can be made not only of a metal (a material of high strength) but also of a synthetic resin, thereby increasing the options for the material of the operation member 91C. Since the operation member 91C made of a synthetic resin can reduce not only the production cost of the operation member 91C (consequently of the headphone 1C) but also the weight of the headphone 1C, the load on the user wearing the headphone 1C can be reduced.

Incidentally, it should be understood that the scope of the invention is not limited to the above-described exemplary embodiments but includes modifications and improvements that do not hamper the achievement of an object of the invention.

In the exemplary embodiments, the drive member for moving the restricting members <NUM>, <NUM>, <NUM> is provided by the operation members <NUM>, <NUM>, 91C each in a form of a dial. However, the drive member (operation member) is not necessarily constructed as described above, but may be any component as long as being capable of moving the restricting members <NUM>, <NUM>, <NUM> to the restricting position and the allowing position. For instance, the operation member is provided by a slide switch or a push switch in some embodiments.

In the exemplary embodiments, the switchers <NUM>, 7A, <NUM>, 9C are configured to restrict the rotation of the piece member <NUM> connected to the connecting member <NUM>, <NUM>, which are connected to the hanger <NUM> (sound emitter <NUM>) via the biasing member <NUM>, to switch the enabled state where the biasing force of the biasing member <NUM> acts on the connecting members <NUM>, <NUM> and the disabled state where the biasing force of the biasing member <NUM> does not act on the connecting members <NUM>, <NUM>. However, the switcher is not necessarily constructed as the above, but is configured, in some embodiments, to disconnect (disengage) the biasing member <NUM> from at least one of the connecting members <NUM>, <NUM> and the piece member <NUM> to switch the enabled state to the disabled state. For instance, a clutch is provided in some embodiments between the restoring portion (biasing member) and the connecting member and/or between the restoring portion (biasing member) and the piece member, the clutch being brought into/out of contact with the restoring portion to switch applying the restoring force by the restoring portion or not.

In the first, third and fourth exemplary embodiments, when the restoring portion <NUM> is disabled, the connecting member <NUM> and, consequently, the sound emitter <NUM> is freely rotatable within the rotation range. Alternatively, as in the second exemplary embodiment, the sound emitter <NUM> is locked at a predetermined angle in some embodiments, thereby enhancing the user-friendliness of the headphone. The structure for locking the sound emitter <NUM> at the predetermined angle is not necessarily the structure described in the second exemplary embodiment but is differently structured in some embodiments.

In the exemplary embodiments, the restoring portion <NUM> includes the biasing member <NUM> in a form of a torsion coil spring. However, the biasing member is not necessarily a torsion coil spring but is other coil spring or a flat spring, or any elastic member capable of applying an elastic force thereof as the restoring force in some embodiments.

In the exemplary embodiments, the sound emitter <NUM> includes the hanger <NUM> for supporting the housing <NUM>. However, the invention is not limited thereto and the hanger <NUM> is not provided in some embodiments. In this case, the housing <NUM> is directly connected to the connecting member <NUM> or <NUM>, or may be connected via other component(s).

In the exemplary embodiments, the restricting members <NUM>, <NUM>, <NUM> are symmetrically arranged with respect to the rotation axis AX3 coaxial with the center axis of the piece member <NUM>. However, the restricting members <NUM>, <NUM>, <NUM> are not necessarily arranged as the above. A single restricting member is provided to the switcher <NUM>, 7A, <NUM>, or 9C in some embodiments, and three or more restricting members are provided to the switcher <NUM>, 7A, <NUM>, or 9C in some embodiments.

In the third and fourth exemplary embodiments, the restricting members <NUM> each include the boss <NUM> to be received in the guide grooves <NUM> and <NUM> of the operation members <NUM> and 91C, respectively, and the curved portion <NUM> (pushed portion) to be pushed by the push portions <NUM>, <NUM>. However, the above arrangement is not exhaustive, and the boss <NUM> is not engaged with the operation members <NUM>, 91C in some embodiments as long as the restricting member can be moved in the +D2 direction by the push portion and can be moved in the -D2 direction by, for instance, a biasing member. Further, the boss <NUM> does not necessarily penetrate through the guide <NUM> and project to the outside of the guide <NUM> as long as the restricting member can be moved in the +D2 and -D2 directions. In other words, the restricting member is not necessarily provided with the boss to be engaged with the operation member.

In the above exemplary embodiments, the sound emitter <NUM> is rotatable toward the rear side within a range of <NUM> degrees with respect to the reference position being <NUM> degrees. However, the invention is not limited thereto but the maximum rotation angle of the sound emitter <NUM> can be changed as needed in some embodiments. Specifically, the maximum rotation angle of the sound emitter <NUM> exceeds <NUM> degrees (e.g., <NUM> degrees) in some embodiments. It should be noted that a rotation angle of the sound emitter <NUM> of <NUM> degrees or more would cause twist of the cord connected to the sound-emitting unit <NUM> located in the sound emitter <NUM>, so that the maximum rotation angle is preferably less than <NUM> degrees.

Further, the reference position is defined at the position of each of the sound emitters <NUM> when the sound-emitting surfaces <NUM> face each other (i.e. the position of the sound emitter <NUM> when the sound emitter <NUM> faces an ear of a user) in the exemplary embodiments. However, the invention is not limited thereto but the reference position is defined at other position(s) in some embodiments. Further, the sound emitter <NUM> is not necessarily rotatable from the reference position toward the rear side but toward the front side in some embodiments.

The boss <NUM> in the first and second exemplary embodiments is substantially cylindrical, and the boss <NUM> in the third and fourth exemplary embodiments is a substantially rectangular post with one pair of opposing corners being arc-shaped. However, the invention is not limited thereto but the bosses <NUM> and <NUM> are otherwise shaped (e.g. square column) in some embodiments. For instance, the boss <NUM> has the same shape as the boss <NUM> in some embodiments, and the boss <NUM> has the same shape as the boss <NUM> in some embodiments. It should be noted that the boss of the restricting member can be easily formed with the same shape as the boss <NUM>. Alternatively, with the same shape as the boss <NUM>, the cross sectional area of the boss can be easily enlarged without impairing slidability of the restricting member, thus easily enhancing the strength of the boss.

Claim 1:
A headphone (<NUM>,1A,1B,1C) comprising:
a headband (<NUM>);
a pair of sound emitters (<NUM>), each sound emitter (<NUM>) being provided to a respective end of the headband (<NUM>) and comprising a sound-emitting unit (<NUM>) therein; and
a pair of connectors (<NUM>), each connector (<NUM>) connecting a respective sound emitter (<NUM>) to the respective end of the headband (<NUM>); wherein
each connector (<NUM>) comprises:
a support (<NUM>,5A) that supports the respective sound emitter (<NUM>) so that the sound emitter (<NUM>) is rotatable around a rotation axis along a top-bottom direction in a predetermined rotation range comprising a reference position, wherein the reference position is a position at which sound-emitting surfaces (<NUM>) of the sound-emitting units (<NUM>) face each other; and
a restoring portion (<NUM>,6A) configured to apply a restoring force on the sound emitter (<NUM>), the restoring force urging the sound emitter (<NUM>) to return to the reference position;
the support (<NUM>,5A,<NUM>,8C) comprises:
a connecting member (<NUM>,51A,<NUM>) connected to the sound emitter (<NUM>) and engaged with a first end of the restoring portion (<NUM>,6A); and
a support member (<NUM>,<NUM>,55A,<NUM>,<NUM>,<NUM>) attached to the headband (<NUM>), the support member (<NUM>,<NUM>,55A,<NUM>,<NUM>,<NUM>) supporting the connecting member (<NUM>,51A,<NUM>) so that the connecting member (<NUM>,51A,<NUM>) is rotatable, and
characterized in that
each connector (<NUM>,4A,4B,4C) further comprises a switcher (<NUM>,7A,<NUM>,9C) configured to switch a state in which the restoring force acts on the sound emitter (<NUM>) and a state in which the restoring force does not act on the sound emitter (<NUM>),
the switcher (<NUM>,7A,<NUM>,9C) comprises:
a piece member (<NUM>,71A) engaged with a second end of the restoring portion (<NUM>,6A);
at least one restricting member (<NUM>,<NUM>,<NUM>) configured to restrict a rotation of the piece member (<NUM>,71A); and
a drive member (<NUM>,<NUM>,91C) configured to move the at least one restricting member (<NUM>,<NUM>,<NUM>) to a restricting position at which the rotation of the piece member (<NUM>,71A) is restricted and the restoring force is hence capable of acting on the connecting member (<NUM>,51A,<NUM>), and an allowing position at which the rotation of the piece member (<NUM>,71A) is allowed and the restoring force is hence incapable of acting on the connecting member (<NUM>,51A,<NUM>).