UNDERWATER MASK

Description

RELATED APPLICATIONS

The present application claims priority to Japanese Application Number 2024-200068, filed Nov. 15, 2024, the disclosure of which application is hereby incorporated by reference herein in its entirety.

BACKGROUND OF THE INVENTION

The present invention relates to an underwater mask including a buckle for coupling a head strap to a mask body.

The underwater mask including the buckle for coupling the strap to the mask body has been conventionally known. For example, JP-A-2004-136057 (P2004-136057A) discloses an underwater mask including: a mask body that has a lens frame for fixing a lens and a skirt extending rearward from the lens frame; and a buckle for coupling a head strap to the mask body.

SUMMARY OF THE INVENTION

In an underwater mask disclosed in JP-A-2004-136057 (P2004-136057A), a buckle has an adjuster function capable of adjusting a length of the strap so that the length of the head strap can be adjusted to fit a size of a head of a wearer as appropriate.

However, in the underwater mask disclosed in JP-A-2004-136057 (P2004-136057A), the buckle is integrated with or coupled to the mask body, so that the underwater mask may give an impression of being rough with many projections and depressions in a side view. The mask body having many projections and depressions may cause water flow to become turbulent underwater, generating vortexes that may obstruct the wearer's visibility.

In addition, the operation positions for tightening and loosening the head strap on the head section differ, which makes it difficult for the wearer to understand and results in poor operability. Further, a figure eight ring is required to prevent the folded-back part of the head strap from flapping, which increases the number of parts.

An object of the present invention is to provide an underwater mask that is an improvement over conventional underwater masks and that includes a buckle which is separate from the mask body and has excellent operability.

In order to achieve the above object, the present invention is directed to an underwater mask that has an up-down direction, a front-rear direction, and a horizontal direction, and includes a mask body, a head strap coupled to the mask body, and a buckle for adjusting the length of the head strap.

In the underwater mask according to the present invention, the buckle is separate from the mask body, is positioned at a distance in the front-rear direction, and has an engaging claw that engages with an engagement recess positioned on an outer surface of the head strap, and a pair of operation portions positioned opposite each other in the up-down direction, and when the buckle is moved rearward, the engaging claw engages with the engagement recess of the head strap to regulate adjustment of the length of the head strap, and when the operation portions are pressed, the regulation is removed.

Embodiments described below relate to the underwater mask shown in FIGS. 1 to 8B, and include optional and preferable features as well as essential features of the present invention.

• • (1) The buckle has a base member and a cover member separate from the base member, the cover member is rotatably attached to the base member and has the operation portions, and when the operation portions are pressed, the cover member moves in a direction away from the base member.
  • (2) The cover member has an outer circumferential wall having a center opening that opens outward in a horizontal direction X, front and rear insertion holes, and an engaging structure positioned within the outer circumferential wall, the engaging structure is coupled to the outer circumferential wall via an elastic portion extending from the outer circumferential wall, and has a pair of side portions extending in the horizontal direction so as to incline rearward, and an engaging projection positioned between the side portions, and the sharp-pointed engaging claw is positioned at inner ends positioned on the inner side in the horizontal direction of the side portions.
  • (3) The base member has a bottom wall, side walls that rise from the bottom wall and extend in the front-rear direction opposite each other in the up-down direction Y, front and rear insertion holes, and an engaged structure positioned at a distance from the bottom wall so as to connect the side walls, and the engaged structure has an engaged surface to which the engaging projection of the cover member is engaged.
  • (4) The base member has a rib on an inner surface of the bottom wall, the rib being positioned opposite the engaging claw of the cover member.

According to the underwater mask of the present invention, the buckle is separate from the mask body and positioned at a distance in the front-rear direction, so that the mask body has a neat appearance in a side view and can suppress turbulence of water flows near the mask body underwater. In addition, the length adjustment of the head strap can be regulated by moving the distal end portion of the buckle or the head strap rearward, while the regulation can be removed by pressing the operation portions, so that the underwater mask has excellent operability.

BRIEF DESCRIPTION OF DRAWINGS

The drawings illustrate specific embodiments of an underwater mask according to the present invention including optional and preferred embodiments as well as essential features of the invention.

FIG. 1 is a perspective view of an underwater mask according to the present invention.

FIG. 2A is a side view of a buckle. FIG. 2B is an enlarged plan view of a portion of a head strap.

FIG. 3A is a front perspective view of the buckle. FIG. 3B is a rear perspective view of the buckle.

FIG. 4 is a front exploded perspective view of the buckle.

FIG. 5 is a rear exploded perspective view of the buckle.

FIG. 6A is a cross-sectional view taken along line VI(a)-VI(a) of FIG. 3A. FIG. 6B is a perspective cross-sectional view of the buckle.

FIG. 7A is a cross-sectional view taken along line VII(a)-VII(a) of FIG. 2A. FIG. 7B is a cross-sectional view taken along line VII(b)-VII(b) of FIG. 2A.

FIG. 8A is a view similar to FIG. 7A but showing the head strap in an unfastened state. FIG. 8B is a view similar to FIG. 7B but showing the head strap in an unfastened state.

DESCRIPTION OF EMBODIMENTS

Referring to the accompanying drawings, details of an underwater mask 10 according to the present invention are described as follows. In FIG. 1, a front-rear direction of the underwater mask 10 is represented by Z, an up-down direction by Y, and a horizontal direction by X. A line C-C represents an imaginary center line bisecting a dimension of the underwater mask 10 in the horizontal direction X. The underwater mask 10 is symmetrical with respect to the imaginary center line C-C. Inward (inside) in the horizontal direction X means a direction toward the imaginary center line C-C, and outward (outside) in the horizontal direction X means a direction opposite to the inward direction.

In each drawing, for ease of explanation, a head strap 20 and insertion holes through which the head strap 20 is inserted are indicated in light gray.

As shown in FIG. 1, the underwater mask 10 includes a mask body 13 including a lens frame 12 in which a pair of lenses 11 are fixed and a flexible skirt 15 extending rearward from the lens frame 12, the head strap 20, and buckles 30 configured to adjust the length of the head strap 20. In an example shown in the drawings, the pair of lenses 11 are formed of a pair of transparent plates; however, one continuous transparent plate may be used.

The lens frame 12 and the buckles 30 are made of a hard plastic material. On the other hand, the skirt 15 and the head strap 20 are made of a soft material such as a natural or synthetic rubber, a silicone resin, or a thermoplastic synthetic resin.

Wound portions 18 for attaching the head strap 20 to the mask body 13 are positioned on both sides of the skirt 15.

Referring to FIGS. 1, 2A and 2B, the head strap 20 includes a bifurcated center portion 21 to be brought into contact with the back of the head of a wearer, and first and second extending portions 22 and 23 on both sides of the center portion 21. The head strap 20 includes an inner surface 20a that faces the face of the wearer, and an outer surface 20b on the opposite side of the inner surface 20a. The outer shape of the head strap 20 may be any known shape in addition to the illustrated example.

The outer surface 20b of the first and second extending portions 22 and 23 includes a plurality of engagement recesses (engaging grooves) 25 arranged at intervals in a length direction and a horizontal direction of the head strap 20, and a flat portion 26 among the plurality of engagement recesses 25. That is, the flat portion 26 is a portion where the plurality of engagement recesses 25 are not formed in the outer surface of the head strap 20.

Furthermore, the first and second extending portions 22 and 23 are adjacent to the center portion 21 when the first and second extending portions 22 and 23 are in a reverse state via wound portions 18, and include base end portions 22B and 23B on a face side of the wearer and distal end portions 22A and 23A facing the base end portions 22B and 23B. The following description includes only the first extending portion 22 of the first and second extending portions 22 and 23 of the head strap 20, and one of the buckles 30. However, the second extending portion 23 has the same configuration. However, the buckle 30 may be attached to only one of the first and second extending portions 22 and 23 of the head strap 20 as needed.

Referring to FIGS. 3A and 3B, the buckle 30 has an inner surface 30a that faces the face of the wearer and an outer surface 30b positioned opposite the inner surface 30a, a front end portion 31, a rear end portion 32, an intermediate portion 33 positioned between the front and rear end portions 31, 32, and a pair of operation portions 34 positioned opposite each other in the up-down direction Y.

The buckle 30 includes a base member 40 and a cover member 60 that is separate from the base member 40 and is separably attached to the base member 40. The buckle 30 also has a transverse center line Q that bisects the dimension in a front-rear direction Z (see FIG. 6A).

In the underwater mask 10 according to the present invention, the buckle 30 for adjusting the length of the head strap 20 is separate from the mask body 13 and positioned at a distance in the front-rear direction Z, so that the mask body 13 has a neat appearance in a side view. If the side surface of the mask body 13 has a rough outer shape with many projections and depressions, there is a risk that the water flow will be turbulent underwater, generating vortexes that will obstruct visibility, but this can be avoided.

The buckle 30 may be made of various known materials, such as natural or synthetic rubber, plastic, and metal, without any restrictions. The base member 40 and the cover member 60 are made of flexible materials, and the cover member 60 is preferably made of a material that is more flexible than the base member 40. By making the cover member 60 more flexible than the base member 40, it can be said that the operation portions 34 of the cover member 60 can be easily flexibly deformed when adjusting the length of the head strap 20, and the operation portions 34 can easily move the cover member 60 in a direction away from the base member 40.

In addition, the base member 40 and the cover member 60 are preferably made of different materials. If they are made of the same material, abnormal noise (resonance) is likely to occur when the lock mechanism formed by an engaged structure 50 and an engaging structure 70 is locked. However, making them of different materials suppresses such abnormal noise. Specifically, the cover member 60 can be made of polyacetal resin, and the base member 40 can be made of polycarbonate resin, for example.

Referring to FIGS. 4 and 5, the base member 40 has front and rear ends 40a and 40b, a bottom wall 41 that is positioned opposite the head of the wearer, side walls 42 that rise from the bottom wall 41 and extend in the front-rear direction Z while facing each other in the up-down direction Y, a front insertion hole 43 positioned on the front end 40a side, and the engaged structure 50 positioned away from the bottom wall 41 so as to connect the side walls 42. A rear insertion hole 45 is formed between the rear end of the engaged structure 50 and the rear ends of the side walls 42. The rear insertion hole 45 communicates with the front insertion hole 43 in the front-rear direction Z to form a base insertion hole through which the base end portion 22B of the head strap 20 is inserted.

The engaged structure 50 has an engaged portion 51 that protrudes toward the cover member 60 and side guide protrusions 52 that are positioned on both sides of the engaged portion 51 in the up-down direction Y.

A shaft portion 46 protruding in the up-down direction Y is positioned on the rear end 40b side of the side walls 42 of the base member 40, and pressed projections 47 protruding in the up-down direction Y and adapted to come into contact with pressing projections 34b of the operation portions 34 of the cover member 60 are positioned on the front end 40a side of the side walls 42. A through hole 48 is formed in the center portion of the bottom wall 41 of the base member 40.

The cover member 60 has front and rear ends 60a and 60b, an outer circumferential wall 62 having a center opening 61 that opens outward in the horizontal direction X, a front insertion hole 63 positioned on the front end 60a side of the outer circumferential wall 62, a rear insertion hole 64 positioned on the rear end 60b side of the outer circumferential wall 62, and an engaging structure 70 positioned within the outer circumferential wall 62. The rear end of the outer circumferential wall 62 has a shape that gradually becomes thinner rearward.

The engaging structure 70 is coupled to the outer circumferential wall 62 via elastic portions (arm portions, coupling portions) 75 extending inward from the rear end side of the outer circumferential wall 62, and has a pair of side portions 71 extending in the horizontal direction X so as to incline rearward from the elastic portions 75, and an engaging projection 72 positioned between the side portions 71 and having a shorter length in the horizontal direction X than the side portions 71. Protrusions 73 protruding outward are formed at the outer ends positioned on the outer side in the horizontal direction X of the side portions 71. Sharp-pointed engaging claws 74 are positioned at the inner ends positioned on the inner side in the horizontal direction X of the side portions 71. The engaging projection 72 has a substantially triangular shape in a cross-sectional view.

The engaged structure 50 is coupled to the outer circumferential wall 62 only at the elastic portions 75, and other portions are not fixed. In the lock mechanism formed by the engaged structure 50 and the engaging structure 70, the engaging projection 72 is biased rearward by the elastic action of the elastic portions 75 so as to abut against the engaged portion 51.

When the length of the head strap 20 is adjusted, the elastic portions 75 twist and the engaging projection 72 slides from the engaged portion 51.

A pair of shaft holes 66, through which the shaft portion 46 of the base member 40 is inserted, are positioned on the rear end 60b side of the outer circumferential wall 62 of the cover member 60. The operation portions 34 are positioned on both sides (upper and lower sides) of the outer circumferential wall 62. Each operation portion 34 has a base end positioned near the shaft holes 66 and an extending portion that is spaced apart from the outer circumferential wall 62 and extends forward from the base end. A plurality of projections 34a aligned in the front-rear direction are positioned on the outer surface of the extending portions of the operation portions 34.

Referring to FIG. 6A, when the buckle 30 is in use, the shaft portion 46 of the base member 40 is inserted into the shaft holes 66 of the cover member 60, and the cover member 60 is attached to the base member 40 so as to be rotatable in the direction of arrow R1. The base end portion 22B of the first extending portion 22 of the head strap 20 is inserted into the base insertion hole of the base member 40, and the distal end portion 22A is inserted into a cover insertion hole of the cover member 60.

In the assembled state of the buckle 30, the engaging projection 72 of the engaging structure 70 of the cover member 60 is positioned opposite the engaged portion 51 of the base member 40 in the horizontal direction X, and the engaging projection 72 is engaged with the engaged portion 51. In assembling the buckle 30, the cover member 60 is pressed against the base member 40 with the shaft portion 46 of the base member 40 inserted into the shaft holes 66 of the cover member 60, whereby the engaging projection 72 of the cover member 60 moves toward the bottom wall 41 of the base member 40 while sliding against the engaged portion 51, and the engaging projection 72 is engaged with the engaged portion 51, and the cover member 60 and the base member 40 are coupled to each other.

The engaged portion 51 of the base member 40 has a front region 81 that abuts against the engaging projection 72 of the cover member 60, and a rear region 82 that extends rearward from the front region 81. The front region 81 of the engaged portion 51 has an engaged surface 83 that abuts against the engaging projection 72, and a protrusion 84 that extends outward in the horizontal direction X from the engaged surface 83. The rear region 82 of the engaged portion 51 extends rearward from the front region 81 so as to become gradually thinner, and its rear end has a rear protrusion 85 that is convexed slightly outward in the horizontal direction.

FIG. 6B shows, by arrow E, the direction of movement of the distal end portion 22A of the first extending portion 22 of the head strap 20 in attaching the buckle 30 to the head strap 20. As illustrated in the diagram, first, the distal end portion 22A of the head strap 20 is inserted into the buckle 30 from the rear end 40b of the base member 40 and inserted into the base insertion hole. Next, the distal end portion 22A is hung around the wound portion 18 of the mask body 13, reversed, and inserted into the front insertion hole 63 positioned on the front end 60a side of the cover member 60. The distal end portion 22A abuts against the inclined front surface of the engaging structure 70 and is guided upward. The wearer picks up the upwardly directed distal end portion 22A, inserts it between the engaging structure 70 and the outer circumferential wall 62, pulls it downward so as to pass under the outer circumferential wall 62, and pulls it out from the rear insertion hole 64, whereby the distal end portion 22A is inserted into the cover insertion hole.

As described above, the engaging structure 70 has an inclined front surface, and thus can function as a guide in inserting the distal end portion 22A of the head strap 20. The rear surface of the engaged structure 50 has a rounded shape, and functions as a guide in pulling the distal end portion 22A downward so as to pass under the outer circumferential wall 62. The rear protrusion 85 that protrudes outward in the horizontal direction X at the rear end of the engaged structure 50 can function as a guide that guides the distal end portion 22A into the rear insertion hole 64.

With the buckle 30 attached as described above, the engaging claws 74 of the engaging structure 70 engage with the engagement recesses 25 of the distal end portion 22A of the head strap 20. In addition to the base end portion 22B of the head strap 20 being locked by the engaging claws 74 of the engaging structure 70, the distal end portion 22A is locked by the protrusions 73, so that the head strap 20 can be more stably fixed to the buckle 30 and the head of the wearer can be further tightened starting from the portion locked by the protrusions 73 with an increased fit.

A pair of ribs 49 is positioned on the inner surface of the bottom wall 41 of the base member 40, protruding to face the pair of engaging claws 74 of the cover member 60 and extending in the front-rear direction Z. When the base end portion 22B of the head strap 20 is inserted into the base insertion hole, the engaging claws 74 are engaged with the engagement recesses 25, and the base end portion 22B is clamped between the engaging claws 74 and the ribs 49, thereby enabling a more stable engagement than in the case where the ribs 49 are not present.

As an option, the substantially square through hole 48 is formed in the bottom wall 41 of the base member 40. The through hole 48 is positioned opposite the lock mechanism formed by the engaged structure 50 and the engaging structure 70 in the horizontal direction X. Therefore, if the lock mechanism cannot be unlocked by an operation of unlocking, for example, an operating rod can be inserted into the through hole 48 and the engaging projection 72 can be pushed up via the base end portion 22B of the head strap 20 to unlock the lock mechanism.

Referring to FIGS. 6A, 7A, and 7B, in the assembled state of the buckle 30, the rear surface of the engaging projection 72 of the cover member 60 and the engaged surface 83 of the engaged portion 51 of the base member 40 are in contact with each other in an inclined manner with respect to the transverse center line Q. In the worn state of the underwater mask 10, a pulling force is applied to the distal end portion 22A of the head strap 20 inserted into the cover insertion hole of the cover member 60 in the direction of arrow K1, and a pulling force is applied to the base end portion 22B inserted into the base insertion hole of the base member 40 in the direction of arrow K2.

In the worn state, when the wearer picks up the buckle 30 or the distal end portion 22A of the head strap 20 and pulls it rearward, the engaging structure 70 has required flexibility and is biased rearward by the elastic portion 75, so that the engaging claws 74 positioned at its inner end engages with the engagement recesses 25 of the base end portion 22B of the head strap 20, and the base end portion 22B is clamped between the engaging claws 74 and the ribs 49 of the bottom wall 41. This restricts the movement of the head strap 20, and the head strap 20 is locked.

Thus, according to the underwater mask 10 of the present invention, the wearer can easily regulate the movement of the head strap 20 simply by picking up the buckle 30 or the distal end portion 22A and moving it rearward, which leads to excellent operability.

As shown in FIG. 6A, an intersection angle α between an imaginary line T connecting a pivot axis AX of the cover member 60 relative to the base member 40 and a center point O of the engaged surface 83 of the engaged portion 51 (the point at which the length dimension of the engaged surface 83 is equal) and the engaged surface 83 on the inside of the horizontal direction X is 20 to 60°, preferably 40 to 50°.

If the intersection angle α is less than 20°, the engaging projection 72 is more upright in cross section than in the illustrated form, and the force exerted by the base end portion 22B of the head strap 20 to press the engaging projection 72 against the engaged portion 51 may act to separate the cover member 60 apart from the base member 40. On the other hand, if the intersection angle α is more than 60°, the engaging structure 70 is more inclined in cross section than in the illustrated form, and the engaging claws 74 are more tightly engaged in the engagement recesses 25, making it difficult for the engaging claws 74 to come out of the engagement recess 25 when adjusting the length of the head strap 20.

The protrusion 84 is positioned on the front end 40a side of the engaged portion 51 of the base member 40, and is formed thicker than the rear end 40b side. Accordingly, even if the buckle 30 is subjected to an external shock or the like, it is possible to prevent the engaging projection 72 from unexpectedly climbing over the engaged portion 51 outward in the horizontal direction X, which would uncouple the cover member 60 and the base member 40.

The side portions 71 of the engaging structure 70 of the cover member 60 are formed relatively thin, with a thickness dimension D1 of 1.0 to 1.5 mm. In this manner, the side portions 71 of the engaging structure 70 are formed relatively thin to the extent that they have the required strength, so that they can bend to follow the movement of the head strap 20 without breaking, and can prevent the engagement by the engaging claws 74 from being released.

Referring to FIGS. 7B, 8A, and 8B, in adjusting the length of the head strap 20, the wearer picks up the buckle 30 with one hand and presses the pair of operation portions 34 of the cover member 60 in the direction of the arrow P1, whereby the pressing projections 34b of the operation portions 34 come into sliding contact with the pressed projections 47, and the cover member 60 moves outward in the horizontal direction X so as to separate apart from the base member 40. Accordingly, a gap S1 is formed between the front end portion of the cover member 60 and the front end portion of the base member 40, the engaging claws 74 and the engagement recesses 25 are disengaged from each other, and the base end portion 22B of the head strap 20 that has been clamped between the engaging claws 74 and the bottom wall 41 of the base member 40 becomes free.

In this manner, when the wearer presses the pair of operation portions 34 with one hand and picks up the distal end portion 22A of the head strap 20 with the other hand and pulls it in the direction opposite to arrow K1, the outer peripheral dimension of the head strap 20 decreases at the time of wearing, thereby increasing the fastening force of the head strap 20. On the other hand, when the wearer moves the distal end portion 22A in the direction of arrow K1 so as to push it into the buckle 30, the outer peripheral dimension of the head strap 20 increases, thereby decreasing the fastening force of the head strap 20.

When the wearer adjusts the length of the head strap 20 to fit the size of his/her head and then takes his/her fingers off the operation portions 34, the pressing projections 34b of the operation portions 34 slide against the pressed projections 47, and the cover member 60 moves inward in the horizontal direction X so as to approach the base member 40, and returns to the original state before the pressing operation. In this state, the wearer picks up the buckle 30 or the distal end portion 22A and pulls it rearward, whereby the engaging claws 74 engage with the engagement recesses 25, thereby enabling the movement of the head strap 20 to be regulated and locked.

In this manner, the wearer can easily and freely change the length of the head strap 20 by picking up and pressing the buckle 30 with one hand while pulling or pushing the distal end portion 22A of the head strap 20 with the other hand, resulting in excellent operability.

Although not shown, the buckle 30 may be integrally molded. For example, the buckle 30 can be integrally molded such that the rear end portion 32 of the buckle 30 is inseparable, and the intermediate portion 33 and the front end portion 31 are separable. However, since the buckle 30 is made up of separate parts as in the present embodiment, the manufacturing process can be simpler and manufacturing costs can be reduced compared to when the buckle 30 is integrally molded.

The buckle 30 is formed of two members, the base member 40 and the cover member 60, so that the number of parts is relatively small, the manufacturing cost can be reduced, and the assembly is easy. In addition, the base member 40 and the cover member 60 are separate, so that even if the elastic portion 75 of the cover member 60 is damaged, for example, the base member 40 can be reused by replacing only the cover member 60, which is excellent in economic efficiency.

Various known materials generally used in this kind of field can be used without limitation for constituent materials included in the underwater mask 10, unless otherwise described in this specification.