Patent Description:
Headphones including a pair of left and right housings in which speaker drivers that output audio signals as sounds are respectively housed, and a headband that connects the pair of left and right housings is known (see, for example, <CIT>). In the headphones, ear pads that cover entire ears of a wearer are provided on facing surfaces of the pair of left and right housings. This type of headphones (so-called over-ear type headphones) is worn in a state where the headband is expanded and the entire wearing surfaces of the ear pads fit peripheries of the ears to sandwich both side head portions of the wearer.

However, in the configuration of <CIT>, when a head size of the wearer is large, due to an external force from the wearer in a direction in which the pair of left and right housings are separated from each other, a stress (elastic restoring force) of the expanded headband is increased and a lateral pressure received from the ear pads is increased. Therefore, the peripheries of the ears of the wearer may hurt and a wearing feeling of the wearer may deteriorate.

Further, patent literature document <CIT> discloses providing a headphone capable of fine adjustment of side pressure without replacement of parts. A headphone including a leaf spring having a shape that is curved corresponding to a head of a user; a pair of housings respectively provided at both end sides of the leaf spring to house sound source units; an ear pad attached to each housing; an adjustment member disposed outside the leaf spring for adjusting a distance between both ends of the leaf spring; and a position adjusting mechanism disposed outside the leaf spring for adjusting the position of the adjusting member with respect to the leaf spring.

The present disclosure has been made in view of the above-described related-art circumstances, and an object thereof is to provide headphones that prevent a variation in a lateral pressure from ear pads of the headphones due to a head size of a wearer, and that provide a comfortable wearing feeling of the headphones regardless of the head size of the wearer.

Aspect of non-limiting embodiments of the present disclosure relates to provide headphones as defined in claim <NUM>.

According to the present disclosure, it is possible to prevent a variation in a lateral pressure from the ear pads of the headphones due to a head size of a wearer, and it is possible to provide a comfortable wearing feeling of the headphones regardless of the head size of the wearer.

Hereinafter, an embodiment specifically disclosing headphones according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, unnecessarily detailed description may be omitted. For example, detailed description of a well-known matter or repeated description of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding of those skilled in the art. The accompanying drawings and the following description are provided for a thorough understanding of the present disclosure by those skilled in the art, and are not intended to limit a subject matter recited in the claims.

<FIG> is a perspective view of headphones <NUM> according to a first embodiment. The headphones <NUM> according to the first embodiment include a pair of left and right housings <NUM> in which a pair of speakers that acoustically output an input audio signal as sound are respectively housed. An ear pad <NUM> that is configured to cover an entire ear of a wearer (hereinafter, also referred to as "user") is attached to a facing surface of each of the left and right housings <NUM>. An entire wearing surface of the ear pad <NUM> fits a side head portion including a periphery of the ear of the user in response to being the headphones <NUM> placed on the wearer's head. Accordingly, the headphones <NUM> are worn in a state where the ear pads <NUM> sandwich both left and right side head portions of the user. The pair of left and right housings <NUM> are attached to both ends of a substantially semicircular arc-shaped headband portion <NUM>.

A pair of coupling members <NUM> are respectively provided between both ends of the headband portion <NUM> and the housings <NUM>. Each coupling member <NUM> includes a band connection portion <NUM> connected to the headband portion <NUM>, and a housing support portion <NUM> formed in a Y shape that extends from the band connection portion <NUM> and supports the housing <NUM>. In the coupling member <NUM>, the housing support portion <NUM> that extends from the band connection portion <NUM> rotatably supports a columnar portion <NUM> provided on an outer side surface of each of the left and right housing <NUM> by a support shaft in a diameter direction thereof. That is, each of the left and right housings <NUM> is swingably supported around the support shaft (see above) with respect to the corresponding housing support portion <NUM>. Accordingly, the headphones <NUM> are configured such that the wearing surface of the ear pad <NUM> freely swings and fits in accordance with a head size different depending on the user. Here, for convenience, the head size different depending on the user is defined as, for example, a size S, a size M, and a size L in ascending order. The head size of the user is not limited to these three sizes, and is merely provided as an example for the sake of convenience in order to make the description easy to understand.

<FIG> is a perspective view of the headband portion <NUM> shown in <FIG>. Slide portions <NUM> of the coupling members <NUM> are respectively inserted into both ends of the headband portion <NUM>. The slide portions <NUM> include tongue piece portions <NUM> being slidably inserted in the headband portion <NUM> from end members <NUM>. The end members <NUM> are fixed to both end portions of the headband portion <NUM>. When the tongue piece portion <NUM> is pulled out by a predetermined length from the end member <NUM> by an operation of the user, the pulling out of the tongue piece portion <NUM> is restricted by a stopper. Accordingly, a length between both end portions of the headband portion <NUM> can be adjusted in accordance with the head size of the user. In the headphones <NUM>, the slide adjustment mechanism by the slide portions <NUM> or the tongue piece portions <NUM> may be omitted.

A cable <NUM> connected to substrates or the like provided on the left and right housings <NUM> is inserted into the headband portion <NUM>. The cable <NUM> can follow displacement in a length due to a movement of the slide portion <NUM> since the cable <NUM> is bent and housed in a wave shape. Both ends of the cable <NUM> are led out from the slide portions <NUM> and drawn into the left and right housings <NUM>.

The headband portion <NUM> includes a pair of holding members <NUM> and a belt-shaped cover member <NUM>. The pair of holding members <NUM> including the end members <NUM> are provided at both end portions of the headband portion <NUM>. In the headphones <NUM>, the belt-shaped hollow cover member <NUM> is provided between the pair of holding members <NUM> and is formed in a substantially semicircular arc shape. The pair of holding members <NUM> are formed of, for example, hard plastic that is difficult to deform (in other words, has high rigidity). In contrast, the cover member <NUM> is made of a material softer than the holding member <NUM>. Accordingly, in the headphones <NUM>, the cover member <NUM> is easily expanded by an operation of the user. A plurality of parallel slits <NUM> for facilitating deformation in an expanding direction of the headband portion <NUM> are provided in a radially inner surface of the cover member <NUM>. The pair of holding members <NUM> and the cover member <NUM> house a substantially semicircular arc-shaped headband spring <NUM>. In other words, the headband spring <NUM> is covered by the belt-shaped hollow cover member <NUM> and the pair of holding members <NUM>.

<FIG> is an enlarged view of a main part in the vicinity of stepped screws of the headband portion <NUM> shown in <FIG>. The headband spring <NUM> is housed in both the cover member <NUM> and the holding members <NUM>. The headband spring <NUM> is formed in, for example, a plate spring shape, and is expandable by being bent in a substantially semicircular arc shape in a longitudinal direction orthogonal to a plate width direction of the headband spring <NUM>. A central portion of the headband spring <NUM> is disposed in the vicinity of a head top portion of the user, and both end portions of the headband spring <NUM> housed in the holding members <NUM> are arranged on both side head portions of the user. A plurality of oval punched portions <NUM> are formed in the headband spring <NUM> along the longitudinal direction of the headband spring <NUM>. A bridge portion <NUM> is formed between the adjacent punched portions <NUM>.

In the headband spring <NUM>, the bridge portion <NUM> disposed on the holding member <NUM> is held to the holding member <NUM> by a pair of stepped screws <NUM>. The pair of stepped screws <NUM> is arranged on both edge portions <NUM> of the headband spring <NUM> in a plate-width direction of the headband spring <NUM>.

Here, as described above, the pair of holding members <NUM> have rigidity that restricts elastic deformation of the headband spring <NUM> in a plate thickness direction of the headband spring <NUM>. Both end portions of the head band spring <NUM> are inserted into and held by the holding members <NUM>. Therefore, the headband spring <NUM> is elastically deformed mainly at a portion not drawn into the holding members <NUM>.

The holding member <NUM> includes a pair of pressing plate portions <NUM> that are arranged in parallel to each other and hold the both edge portions <NUM> of the headband spring <NUM> in the plate thickness direction of the headband spring <NUM>. The holding member <NUM> is provided with a clearance C (see <FIG>) between the pressing plate portions <NUM> and the headband spring <NUM>. More specifically, the pressing plate portions <NUM> are formed to protrude inward in a plate width direction of the headband spring <NUM> and are arranged on an upper side of a groove <NUM> (see <FIG>) that houses the headband spring <NUM>. A distance of the groove <NUM> that houses the headband spring <NUM> in the plate thickness direction of the headband spring <NUM> is formed to be, for example, <NUM>. A plate thickness of the headband spring <NUM> housed in the groove <NUM> is formed to be, for example, <NUM>. Therefore, in a state where the headband spring <NUM> is close to one side of the groove <NUM>, the clearance C is <NUM>. In the headphones <NUM>, the clearance C serves as a play of the headband spring <NUM> and is held by the holding members <NUM>. The pair of pressing plate portions <NUM> may also be provided on the cover member <NUM>.

<FIG> is an enlarged view of a main part in the vicinity of stepped screws of the headband portion shown in <FIG> when viewed from an angle different from the angle of <FIG>. The pair of stepped screws <NUM> pass through both end side portions of the headband spring <NUM> in the plate thickness direction and are screwed to the holding member <NUM>. A male screw portion <NUM> (see <FIG>) is formed at a tip end of the stepped screw <NUM>. On a base end side of the male screw portion <NUM>, a shaft portion <NUM> formed in a columnar shape having an outer diameter larger than that of the male screw portion <NUM> is formed. At a base end of the shaft portion <NUM>, a flange portion <NUM> having a diameter larger than that of the shaft portion <NUM> is formed. For example, a cross hole <NUM> is coaxially recessed in a base end surface of the flange portion <NUM>. In the stepped screw <NUM>, the male screw portion <NUM> is screwed into the holding member <NUM>, and the exposed shaft portion <NUM> is inserted into an insertion hole <NUM> of the headband spring <NUM> (see <FIG>). The insertion hole <NUM> has an inner diameter larger than an outer diameter of the shaft portion <NUM> and smaller than an outer diameter of the flange portion <NUM>. That is, the stepped screw <NUM> holds the headband spring <NUM> movably in an axial direction of the stepped screw <NUM> with a gap larger than the plate thickness of the headband spring <NUM> between the flange portion <NUM> and the holding member <NUM>.

<FIG> is a side cross-sectional view of a stepped screw position of the headband portion <NUM>. Since the headband spring <NUM> is held by the holding member <NUM> with the clearance C in the plate thickness direction of the headband spring <NUM>, the headband spring <NUM> can be moved in a direction in which the clearance C is reduced (upward direction in <FIG>) in a state shown in <FIG>.

Further, the headphones <NUM> include, at a lead-out tip end portion of the headband spring <NUM> of the holding member <NUM>, a cutout portion <NUM> (see <FIG>) from which the pair of pressing plate portions <NUM> are removed. Since the holding member <NUM> includes the cutout portion <NUM>, the holding member <NUM> functions to release restriction of the pressing plate portions <NUM> that restrict a certain amount or more of elastic deformation of the headband spring <NUM>.

<FIG> is a side cross-sectional view in which the headband spring <NUM> is moved from a position illustrated in <FIG> to a position where the headband spring <NUM> abuts against the flange portion <NUM> of the stepped screw <NUM>. Since the headphones <NUM> are provided with the cutout portion <NUM>, even when the headband spring <NUM> is moved in a direction in which the clearance C reduces or disappears from the state shown in <FIG> and an upper surface of the headband spring <NUM> abuts against a cutout-portion-side tip end portion <NUM>, the headband spring <NUM> can be further moved in the same direction (the upward direction in <FIG>) in the cutout portion <NUM>.

Next, an operation of the headphones <NUM> according to the first embodiment will be described.

The headphones <NUM> according to the first embodiment include the plate-spring-shaped headband spring <NUM>, the pair of holding members <NUM> and the pair of stepped screws <NUM>. The plate-spring-shaped headband spring <NUM> is bent in the substantially semicircular arc shape in the longitudinal direction of the headband spring <NUM> so as to be formed to be expandable. In response to the headphones <NUM> being placed on wearer's head, the central portion of the headband spring <NUM> is disposed in the vicinity of the head top portion of the wearer, and the both end portions headband spring <NUM> are arranged on both side head portions of the wearer. The pair of holding members <NUM> have the rigidity that restricts the elastic deformation of the headband spring <NUM> in the plate thickness direction in the headband spring <NUM>, and are configured to insert and hold the pair of both end portions. The pair of stepped screws <NUM> pass through both end side portions of the headband spring <NUM> in the plate thickness direction and are screwed to the holding member <NUM>, and hold the headband spring <NUM> movably in the axial direction of the pair of stepped screws <NUM> with the gap larger than the plate thickness of the headband spring <NUM> between the flange portions <NUM> and the holding member <NUM>. The pair of stepped screws <NUM> are arranged at both end side portions of the headband spring <NUM> in the plate width direction of the headband spring <NUM>, and the plate width direction is orthogonal to the longitudinal direction of the headband spring <NUM>.

In the headphones <NUM>, the headband spring <NUM> is formed to be bent in the substantially semicircular arc shape. The headband spring <NUM> having a substantially semicircular arc-shape is used by being expandable in a direction in which both end portions of the headband spring <NUM> are separated from each other by an operation of the wearer. The headband spring <NUM> is deformed in a shape closer to a flat surface (a curvature is reduced) by expanding the both end portions of the headband spring <NUM> by the operation of the wearer. At this time, a stress (that is, an elastic restoring force) in a direction in which the both end portions of the headband spring <NUM> approach each other is generated in the headband spring <NUM>. Here, the stress is a magnitude per unit area of an internal force in an opposite direction generated inside the headband spring <NUM> with respect to an external force (that is, a force generated by the operation of the wearer).

When the headphones <NUM> are used for a person having a large head of the size L as compared with a person having a small head of the size S, the headband spring <NUM> is deformed in a shape closer to a flatter surface (that is, the curvature is reduced). Therefore, when the headphones <NUM> are used for the head of the size L rather than the head of the size S, an elastic restoring force (lateral pressure) applied to the both side head portions of the head acts more greatly.

The headphones <NUM> are held by inserting both end portions of the headband spring <NUM> into the pair of holding members <NUM>, respectively. The both end portions of the headband springs <NUM> inserted into the respective holding members <NUM> are held to the holding members <NUM> by the pair of stepped screws <NUM> that pass through the both end side portions of the headband spring <NUM> in the plate thickness direction. The stepped screw <NUM> holds the headband spring <NUM> to the holding member <NUM> with the gap larger than the plate thickness of the headband spring <NUM> between the flange portion <NUM> and the holding member <NUM>. That is, the headband spring <NUM> is held by the stepped screw <NUM> so as to be movable in the axial direction of the stepped screw <NUM>.

For example, in headphones according to a comparative example as a related-art headphones, a headband spring mounted on the headphones is fastened (rigidly fixed) to the holding members <NUM> by fixing screws at the positions of the stepped screws <NUM>. Therefore, in the headphones according to the comparative example, the headband spring has an elastically deformable region between two fixing screw positions in which both end portions are rigidly fixed to the respective holding members <NUM> (see <FIG>) by the fixing screws along a longitudinal direction of the headband spring.

On the contrary, in the headphones <NUM> according to the first embodiment, the position where the headband spring is rigidly fixed to the holding member <NUM> by the fixing screw in the headphones of the comparative example is held movably by the stepped screw <NUM> in the axial direction of the stepped screw <NUM>. As a result, in the headphones <NUM> according to the first embodiment, the elastically deformable region of the headband spring <NUM> becomes longer toward a spring end portion side of the headband spring <NUM> than the fixing screw position according to the comparative example (see <FIG>).

The headband spring <NUM> having substantially the same material and shape as the related-art headband spring has the increased elastically deformable region. Therefore, particularly, even when the both end portions of the headband spring <NUM> are used to be expanded with the head of the size L, it is possible to prevent the lateral pressure applied to the both side head portions of the wearer from greatly acting as compared with the related art. That is, the headphones <NUM> are configured to be able to prevent a lateral pressure variation due to a head size of the wearer. Therefore, according to the headphones <NUM> of the first embodiment, it is possible to prevent the variation in the lateral pressure from the ear pads due to a head size of the wearer, and it is possible to provide a comfortable wearing feeling regardless of the head size of the wearer.

In the headphones <NUM>, the headband spring <NUM> is held by the holding members <NUM> with the clearance C in the plate thickness direction of the headband spring <NUM>.

<FIG> is an operation explanatory diagram illustrating a process of movement of the headband spring <NUM>. In the headphones <NUM> according to the first embodiment, the headband spring <NUM> is held by the holding members <NUM> with the clearance C in the plate thickness direction. At this time, the flange portion <NUM> and the headband spring <NUM> are separated from each other by a distance d larger than the clearance C. The headband spring <NUM> is held to the holding member <NUM> by the stepped screw <NUM> and is movable in the axial direction of the stepped screw <NUM> at a lead-out tip end portion of the holding member <NUM>. In the process of moving the headband spring <NUM> in a direction approaching the flange portion <NUM> of the stepped screw <NUM>, the clearance C provided between the holding member <NUM> and the headband spring <NUM> disappears (C = <NUM>) before the headband spring <NUM> is in contact with the flange portion <NUM>. That is, the movement of the headband spring <NUM> is restricted by the holding member <NUM> before the headband spring <NUM> hits the flange portion <NUM>.

At this time, the flange portion <NUM> and the headband spring <NUM> are still separated from each other by a distance d1 smaller than the distance d.

A gap having the distance d1 exists between the headband spring <NUM> and the flange portion <NUM> in a state where the movement of the headband spring <NUM> is restricted by the cutout-portion-side tip end portion <NUM> of the holding member <NUM>. Since the cutout portion <NUM> is provided, the headband spring <NUM> can be further elastically deformed between the cutout-portion-side tip end portion <NUM> and the stepped screw <NUM> by the distance d1 by which the headband spring <NUM> hits the flange portion <NUM>. Accordingly, the headband spring <NUM> can be displaced (moved) both in a period until the headband spring <NUM> is in contact with the cutout-portion-side tip end portion <NUM> and the clearance C disappears and in a period until the headband spring <NUM> hits the flange portion <NUM> after the headband spring <NUM> is in contact with the cutout-portion-side tip end portion <NUM>.

<FIG> is a diagram showing a movable range of a headband spring <NUM> according to the comparative example. <FIG> shows a movable range of the headband spring <NUM> according to the first embodiment.

Accordingly, in the headphones <NUM>, by using the clearance C and the stepped screws <NUM>, a movable range of the headband spring <NUM> can be secured even in a region where the headband spring cannot be operated in the related art, and elasticity of the headband spring <NUM> can be used in a longer region (range).

In the headphones <NUM>, the holding member <NUM> includes the pair of pressing plate portions <NUM> that are arrange in parallel to each other and hold the plate-width-direction both edge portions <NUM> of the headband spring <NUM> in the plate thickness direction, and the clearance C is provided between the pressing plate portions <NUM> and the headband spring <NUM>.

In the headphones <NUM> according to the first embodiment, the holding member <NUM> includes the pair of pressing plate portions <NUM> that hold the plate-width-direction both edge portions <NUM> of the headband spring <NUM> in the plate thickness direction. The plate-width-direction both edge portions <NUM> of the headband spring <NUM> are pressed by the pair of pressing plate portions <NUM>. The above-described clearance C is provided between the headband spring <NUM> and the pressing plate portions <NUM>. When both end portions of the headband spring <NUM> are expanded and the headband spring <NUM> is deformed in a direction so that the shape of the headband spring <NUM> being closer to the flat surface (the direction in which the curvature is reduced), the headband spring <NUM> is moved in a direction approaching the pressing plate portions <NUM>, and finally is in contact with the pressing plate portions <NUM> to restrict the movement of the headband spring <NUM>.

In the headphones <NUM>, the cutout portion <NUM>, which releases the restriction of the elastic deformation, is formed in the lead-out tip end portion of the headband spring <NUM> of the holding member <NUM> by removing the pair of pressing plate portions <NUM>.

<FIG> is an explanatory diagram of a correlation between a head size and a lateral pressure obtained by comparing the headband spring <NUM> of the comparative example with the headband spring <NUM> of the first embodiment. In <FIG>, a vertical axis represents a lateral pressure [N], and a horizontal axis represents a head-ear height [mm] that varies depending on the heads of the size S to the size L.

In the headphones <NUM> according to the first embodiment, the holding member <NUM> includes, at the lead-out tip end portion of the headband spring <NUM>, the cutout portion <NUM> from which parts of the pressing plate portions <NUM> are removed. Since the pressing plate portions <NUM> exist, the movement of the headband spring <NUM> in a direction approaching the flange portion <NUM> is restricted at the lead-out tip end portion of the holding member <NUM>. The movement of the headband spring <NUM> in the direction approaching the flange portion <NUM> is not restricted at the cutout portion <NUM> where the pressing plate portions <NUM> are not provided. When the headband spring <NUM> is moved in the direction approaching the flange portion <NUM>, the headband spring <NUM> hits the cutout-portion-side tip end portion <NUM> of the pressing plate portions <NUM>. The headband spring <NUM> that hits the cutout-portion-side tip end portion <NUM> can be moved by being bent (elastically deformed) in the direction approaching the flange portion <NUM> in a space between the cutout-portion-side tip end portion <NUM> and the flange portion <NUM> (that is, the cutout portion <NUM>).

Accordingly, the headband spring <NUM> can exert elasticity, which has not been obtained in the related art, in the cutout portion <NUM>. That is, a spring constant can be reduced in a range of the size S to the size L of the heads. As a result, regarding the headphones <NUM>, even when a head size is increased, the lateral pressure can be unlikely to increase as compared with the related-art structure.

In the headphones <NUM>, the headband spring <NUM> arranged between the pair of holding members <NUM> is covered by the belt-shaped hollow cover member <NUM> made of the material softer than material of the holding members <NUM>.

In the headphones <NUM>, both end portions of the headband spring <NUM> formed in the substantially semicircular arc shape are held by the respective holding members <NUM>, and the headband spring <NUM> arranged between the pair of holding members <NUM> is covered by the cover member <NUM>. The cover member <NUM> is formed of the material softer than the material of the holding member <NUM>. The cover member <NUM> can be deformed such that elasticity of the movable region of the headband spring <NUM> is not impaired. As shown in <FIG>, in appearance, the headphones <NUM> have substantially the same cross-sectional shape at any positions from one holding member <NUM> to the other holding member <NUM> via the cover member <NUM>. Accordingly, the headphones <NUM> can house the elastic mechanism portion that can prevent the lateral pressure variation due to a head size in the headband portion <NUM> while having a unified and a good-looking design.

Claim 1:
A headband portion (<NUM>) for headphones (<NUM>) comprising:
a headband spring (<NUM>) having a plate-spring shape, and being bent in a substantially semicircular arc shape so as to be expandable in a longitudinal direction orthogonal to a plate width direction of the headband spring (<NUM>) so that a central portion of the headband spring (<NUM>) is disposed in a vicinity of a head top portion of a wearer and each of both end portions of the headband spring (<NUM>) is arranged on each of both side head portions of the wearer, respectively, in response to the headphones (<NUM>) being placed on the wearer's head, the headband spring (<NUM>) comprising a plurality of oval punched portions (<NUM>) along the longitudinal direction of the headband spring (<NUM>) and bridge portions (<NUM>) formed between the adjacent punched portions (<NUM>);
a pair of holding members (<NUM>) having rigidity to restrict elastic deformation of the headband spring (<NUM>) in a plate thickness direction of the headband spring (<NUM>), wherein the pair of holding members (<NUM>) comprises a pair of pressing plate portions (<NUM>) configured to hold both edge portions (<NUM>) of the pair of both end portions in the plate thickness direction by inserting the pair of both end portions into the pair of holding members (<NUM>), the pair of pressing plate portions (<NUM>) being arranged in parallel to each other, and the both edge portions (<NUM>) being arranged in the plate width direction;
a pair of stepped screws (<NUM>) that passes through the bridge portions (<NUM>) of both end side portions of the headband spring (<NUM>) in the plate thickness direction and is screwed to the pair of holding members (<NUM>), and that holds the headband spring (<NUM>) movably in an axial direction of the pair of stepped screws (<NUM>) with gaps between flange portions (<NUM>) of the pair of stepped screws (<NUM>) and the pair of holding members (<NUM>), the gaps being larger than a plate thickness of the headband spring (<NUM>), and the both end side portions of the headband spring (<NUM>) being arranged in the plate width direction.