WO2009038278A1

WO2009038278A1 - A pillow with multi-layered structure

Info

Publication number: WO2009038278A1
Application number: PCT/KR2008/003875
Authority: WO
Inventors: Seok-Kwan Oh
Original assignee: Seok-Kwan Oh
Priority date: 2007-09-20
Filing date: 2008-07-01
Publication date: 2009-03-26

Abstract

Provided is a pillow which is manufactured by reflecting the structure of an arm pillow of a user, and provides various functions and advantages by using a multi-layered structure in which the respective layers have different compressibility and are deformed differently. The pillow with a multi-layered structure includes an intermediate layer and an outer layer, and may further include a core. The core supports the cervical vertebrae when the head is laid on the pillow. The outer layer includes a first support section formed to cover the intermediate layer and support the cervical vertebrae, and a second support section formed to extend from the first support section and support the head. The outer layer is formed of a soft material, and the internal structure of the pillow is formed of materials whose elasticity and hardness increase toward the center of the pillow. Therefore, the pillow provides softness and elasticity like a person's arm. Further, the shape of the pillow is constantly maintained, so that the normal posture of the cervical vertebrae can be maintained.

Description

Description A PILLOW WITH MULTI-LAYERED STRUCTURE

Technical Field

[1] The present invention relates to a pillow.

Background Art

[2] In general, a variety of different kinds of pillows are used for support and comfort during sleep.

[3] A wooden or stone pillow can keep the height of the cervical vertebrae constant.

However, it may have an adverse effect upon the head, the cervical vertebrae, or the muscles or bone of the neck, and it may hinder blood circulation and cause muscle or nerve damage. When the wooden or stone pillow is very low in height and very hard, the normal curvature of the cervical vertebrae is not maintained, cerebral circulation is hindered, and the user may not sleep soundly.

[4] Meanwhile, people who work with their heads lowered are prone to so-called turtle neck syndrome which causes the neck to become bent at the back and protrude at the front. People with turtle neck syndrome usually prefer a high pillow. However, a high pillow may put strain on the muscles and hinder blood flow. Further, the C-shaped curve of the cervical vertebrae may be bent in the reverse direction.

[5] A pillow filled with feathers or cotton provides comfort. However, when the feather or cotton pillow is too soft, the head and neck may sink into the pillow so deeply that the curve of the cervical vertebrae cannot be maintained. To compensate for this, the height and area of the pillow may be increased. In this case, however, the center of the pillow deviates from the center of gravity of the head such that the pillow is likely to slip out from under the head. This could cause the cervical vertebrae to be abnormally curved.

[6] Recently, latex pillows and memory foam pillows have become popular. They have excellent shock absorbing ability and, unlike the above-described pillows, their stuffing does not gather at one side and they recover their shape after use. However, since latex pillows and memory foam pillows have a high compressibility, they do not maintain the normal posture of the cervical vertebrae during sleep. Further, when the user sleeps on his/her side, the head may droop causing the cervical vertebrae to bend.

[7] Further, posture-correcting pillows have been designed to maintain the normal curvature of the neck, but they are limited in how closely they match the overall shape of the head and neck. Further, they do not feel satisfactory.

[8] Japanese Unexamined Patent Application Publication No. 2005-110702 (Patent

Document 1) discloses a pillow and a method of manufacturing the same. The pillow includes a low repulsive-power core layer formed of polyurethane foam and integrated with a surface layer that is softer than the core layer.

[9] U.S. Patent No. 5,689,844 (Patent Document 2) discloses a multi-layer pillow which includes an internal layer, an intermediate layer, a surface layer, and a plurality of air gaps formed among the layers.

[10] WO 92/03957 (Patent Document 3) entitled "Articles of Bedding and the Like" discloses a pillow that includes a non-rigid core, an intermediate layer, and a surface layer. The intermediate layer and the surface layer are air-impermeable and air flow among the layers is limited.

[11] U.S. Patent No. 4,799,275 (Patent Document 4) discloses a shock absorbing pillow which includes an elastically-deformable core, an impermeable membrane surrounding the core, an element for controlling air flow through the membrane, and a cushion member formed of a fiber layer.

[12] The pillows disclosed in Patent Documents 1 to 4 have a multi-layered structure which sits at a proper height when a user lies on his/her back. In sleep, a load on the head and cervical vertebrae is minimized, which comforts and eases the body.

[13] However, in the pillows disclosed in Patent Documents 1 to 4, since layers of different hardness are discontinuously disposed, their elasticity may deteriorate with use rendering them uncomfortable or ineffective for posture correction. That is, when the pillows are used for a long time, the internal layer, the intermediate layer, or the surface layer may lose its elasticity so that the pillows cannot maintain the normal curvature and alignment of the cervical vertebrae and consequently the user may not sleep in comfort.

[14] In order to obtain maximum benefit from a pillow, the pillow's height and hardness should match the shape of the head and cervical vertebrae, and the hardness should not apply pressure to the muscles or blood vessels. Furthermore, the pillow should be comfortable. However, the pillows disclosed in Patent Documents 1 to 4, the wooden pillow, and the latex or memory foam pillow, are limited in their ability to satisfy all of these conditions. Therefore, there is a demand for a comfortable pillow whose height and hardness remain constant. Disclosure of Invention Technical Problem

[15] The present invention is directed to a pillow with a multi-layered structure, which provides comfort and a posture correction effect.

[16] The present invention is also directed to a pillow that has an arm-pillow structure corresponding to the bone, muscles, soft tissue, and skin of a human body, thereby having advantages of an arm pillow. [17] The present invention is also directed to a pillow which provides elasticity and comfort while constantly maintaining the pillow's shape by using a rigid core, an elastic material layer, and a soft cortex layer.

[18] The present invention is also directed to a pillow that has layers whose heights are set differently at predetermined intervals, so that two or more heights can be chosen.

[19] The present invention is also directed to a pillow that has various cross-sectional structures such that an optimal portion can be selected. Technical Solution

[20] According to an aspect of the present invention, a pillow with a multi-layered structure includes: a core that is formed of a material having a first hardness and a first elasticity to correspond to a bone of a human body; a material layer that is formed on the core, and formed of a material having a second hardness lower than the first hardness and a second elasticity lower than the first elasticity to correspond to a muscle of the human body; and a cortex layer that is formed on the material layer, and formed of a material having a third hardness lower than the second hardness and a third elasticity lower than the second elasticity to correspond to soft tissue and skin of the human body. In a state where a user lays his/her head on the pillow, a portion of the material layer corresponding to the central portion of the pillow may have a first height, and a portion of the material layer corresponding to the peripheral portion of the pillow may have a second height which is larger than the first height, which means that the material layer can have two different heights. The pillow may include an outer fabric formed on the cortex layer. The material layer may be composed of spaces divided on the horizontal cross-section thereof.

[21] According to another aspect of the present invention, a pillow with a multi-layered structure includes: a core that supports the cervical vertebrae of a user, when the user lays his/her head on the pillow; an intermediate layer that is formed to cover the core and supports the cervical vertebrae of the user, when the user lays his/her head on the pillow; and an outer layer that includes a first support section which is formed to cover the intermediate layer and supports the cervical vertebrae of the user, when the user lays his/her head on the pillow, and a second support section which is formed to extend from the first support section and supports a head of the user, when the user lays his/ her head on the pillow. The core may be formed of a material having a first hardness and a first elasticity, the intermediate layer may be formed of a material having a second hardness that is lower than the first hardness and a second elasticity that is lower than the first elasticity, and the outer layer may be formed of a material having a third hardness that is lower than the second hardness and a third elasticity that is lower than the second elasticity. The core may be formed of any one selected from the group consisting of urethane, silicon, and wood. The intermediate layer may be formed of any one selected from the group consisting of high-elasticity polyurethane foam and silicon foam. The intermediate layer may have one or more serrations forming a gap in a first direction to distribute pressure applied by the user when the user lays his/her head on the pillow. The intermediate layer may include one or more holes formed along the longitudinal direction of the intermediate layer. The outer layer may include an opening for reducing stress caused by the user when the user lays his/her head on the pillow. When the head is laid on the pillow, the center of gravity supported by the pillow may move toward the cervical vertebrae. The pillow may further include a hollow portion formed between the outer layer and the intermediate layer. The shape of the hollow portion may be determined by a shape formed by an inner surface of the outer layer and an inclined portion adjacent to the outer boundary of the intermediate layer. The intermediate layer may support both the cervical vertebrae and the head when the head is laid on the pillow. The intermediate layer may have a first region designed to reflect the shape of an arm pillow when a person lies on his/her side and puts his/her head on his/her arm, and a second region designed to reflect the shape of an arm pillow when a person lies on his/her back and puts his/her head on his/her arm. The pillow may further include an air bag formed between the outer layer and the intermediate layer to support the cervical vertebrae and the head.

[22] According to still another aspect of the present invention, a pillow includes an intermediate layer that supports the cervical vertebrae of a user when the user lays his/ her head on the pillow; and an outer layer formed to cover the intermediate layer, the outer layer including a first support section that supports the cervical vertebrae of the user and a second support section that is formed to extend from the first support section and supports a head of the user when the user lays his/her head on the pillow. The intermediate layer may cover the outer layer. Alternatively, the outer layer may cover the intermediate layer.

Advantageous Effects

[23] According to the present invention, the pillow with a multi-layered structure provides stability and comfort by using the rigid core and the elastic cortex layer which provide a feeling like bone and muscle. Therefore, it is possible to enhance the feeling of the pillow.

[24] Further, the pillow with a multi-layered structure according to the present invention includes the first portion which supports the cervical vertebrae of a human body, and the second portion which supports the head of the human body. Therefore, the pillow can provide a posture correction effect.

[25] Further, the pillow can provide comfort from the softness of the outer layer, which is similar to the softness of soft tissue and skin of a human body. [26] Further, the heights of the respective layers are differently set at predetermined intervals. Therefore, when a head is laid on the pillow, two or more heights can be utilized. [27] Further, the pillow with a multi-layered structure according to the present invention constantly maintains the pillow's height and hardness, unlike many conventional pillows. Therefore, the muscles and ligaments of the head or cervical vertebrae can be properly relaxed by the pillow, the posture of the cervical vertebrae can be normally maintained throughout sleep, and comfort can be achieved. [28] Furthermore, the air bag included in the pillow with a multi-layered structure buffers a pressure difference at the boundary between the intermediate layer and the outer layer of the pillow. Further, the air bag can change the structure of the pillow in accordance with the shape of the neck of each individual, thereby enhancing comfort.

Further, the air bag may be manufactured to have a shape that is fitted to the shape of the neck and head of a human body. Therefore, the pressure of the human body can be distributed onto as wide an area as possible to enhance comfort.

Brief Description of the Drawings [29] FIG. 1 is a vertical cross-sectional view of a pillow with a multi-layered structure according to a first example embodiment of the present invention. [30] FIG. 2 is a horizontal cross-sectional view of the pillow shown in FIG. 1.

[31] FIG. 3 is a vertical cross-sectional view of the pillow with a multi-layered structure according to the first example embodiment of the present invention. [32] FIGS. 4 and 5 are diagrams showing a state where the pillow shown in FIG. 3 is used. [33] FIG. 6 is a perspective view of a pillow with a multi-layered structure according to a second example embodiment of the present invention. [34] FIG. 7 is a cross-sectional view of the pillow with a multi-layered structure, taken along A-A line of FIG. 6.

[35] FIG. 8 is a side view of the pillow shown in FIG. 6.

[36] FIG. 9 is a longitudinal cross-sectional view of an intermediate layer of a pillow according to a third example embodiment of the present invention. [37] FIG. 10 is a vertical cross-sectional view of the intermediate layer of the pillow according to the third example embodiment of the present invention. [38] FIG. 11 is a cross-sectional view of a pillow with a multi-layered structure according to a fourth example embodiment of the present invention. [39] FIGS. 12 (a) and (b) are diagrams showing an example of pressure occurring around the pillow of FIG. 6. [40] FIGS. 13 (a) and (b) are diagrams showing a state where an intermediate layer of the pillow shown in FIG. 6 or 11 is used.

[41] FIGS. 14 (a) through (f) are diagrams showing modifications of the pillow of FIG. 6.

[42] FIGS. 15 (a) through (e) are cross-sectional views of modifications of the pillows of

FIG. 14, in which a core is omitted.

[43] FIG. 16 (a) is a perspective view of a pillow according to a fifth example embodiment of the present invention.

[44] FIGS. 16 (b) through (d) are diagrams for explaining an air bag unit of FIG. 16 (a).

[45] FIG. 17 (a) is a diagram showing an air bag unit of a pillow according to a sixth example embodiment of the present invention.

[46] FIG. 17 (b) is a perspective view of an air bag of the air bag unit of FIG. 17 (a).

[47] FIG. 18 (a) is a diagram for explaining change in the shape of the pillow having the air bag when a normal shaped neck and head is laid on the pillow.

[48] FIG. 18 (b) is a diagram for explaining change in the shape of the pillow having the air bag when a straight neck and head is laid on the pillow. Mode for the Invention

[49] Various changes may be made in example embodiments of the present invention, and specific example embodiments will be described with reference to the drawings. However, it should be appreciated that the present invention is not limited to the example embodiments, but includes all changes, equivalents, and substitutes included in the sprit and scope of the present invention. In the respective drawings, like referenc e numerals are attached to the same components. All terms which are used in this specification including technical or scientific terms have the same meaning as generally understood by those skilled in the art, as long as the terms are not defined differently. It should be interpreted that terms defined in a dictionary which is generally used have a meaning corresponding to that in contexts of the relevant art. As long as the terms are not defined clearly in this specification, the terms are not interpreted as ideal or excessively formal.

[50] Hereinafter, example embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[51] FIG. 1 is a vertical cross-sectional view of a pillow with a multi-layered structure according to a first example embodiment of the present invention. FIG. 2 is a horizontal cross-sectional view of the pillow shown in FIG. 1. FIG. 3 is a vertical cross-sectional view of the pillow with a multi-layered structure according to the first example embodiment of the present invention. FIGS. 4 and 5 are diagrams showing a state where the pillow shown in FIG. 3 is used.

[52] As shown in FIGS. 1 and 2, the pillow 10 with a multi-layered structure according to the first example embodiment of the present invention includes a core 20 positioned in pillow's center. The core 20 is formed of a rigid material. [53] The core 20 may be formed of a material selected from synthetic bone, wood, plastics, and so on.

[54] The core 20 is wrapped in a material layer 22.

[55] The material layer 22 is formed to have elasticity similar to that of muscle tissue of a human body. Therefore, the material layer 22 may be formed of high-elasticity polyurethane foam or the like. [56] As shown in FIGS. 3, 4, and 5, the material layer 22 may be constructed in such a manner that pillow's compressibility differs at predetermined intervals. Therefore, the pillow can have two or more effective heights (a) and (b). [57] The effective height (a) when a user lies on his/her side (A) as shown in FIG. 4 is different from the effective height (b) when the user lies on his/her back (B) as shown in FIG. 5. The pillow adjusts to the appropriate effective height when the user turns. [58] The material layer 22 may be constructed to have a different cross-sectional shape at predetermined intervals(or sections). For example, the material layer 22 may have a circular cross-section at one interval(or section) and a rectangular cross-section at another interval(or section). Therefore, the user can select a specific portion that he/she wants to sleep on. [59] In this case, the horizontal cross-section of the entire pillow may be formed in various shapes such as a circle and an ellipse. [60] The material layer 22 may be constructed to have an irregular cross-sectional shape such as a flower or saw-toothed shape. [61] The material layer 22 has a cortex layer 24 formed around the material layer 22. The cortex layer 24 gives a cortical sensation. The cortex layer 24 may be formed of low- elasticity polyurethane foam or latex foam. [62] The cortex layer 24 may be wrapped in an outer fabric 26 made of non- woven fabric, as shown in FIGS. 1 and 2. [63] The pillow 10 constructed in such a manner has a structure close to the arm of a human body. Therefore, when a user lays his/her head on the pillow, he/she can experience the comfort of laying his/her head in his/her mother's arm. [64] The material layer 22, which supports the cervical vertebrae, has elasticity similar to that of muscle. Therefore, the material layer 22 provides comfort to the cervical vertebrae.

[65] The cortex layer 24 provides softness similar to that of soft tissue and skin.

[66] The pillow may be constructed in such a manner that pillow's compressibility differs at predetermined intervals along the longitudinal direction of the pillow. When the compressibility of the pillow is differently set at each interval along the longitudinal direction of the pillow, it is possible to obtain an effect where a user can have a sleep while changing the height of the pillow.

[67] Further, the material layer 22 may be constructed to have a different cross-sectional structure at each interval.

[68] In FIGS. 6 to 19, which are diagrams for explaining other example embodiments according to the present invention, components that are the same as in the pillow shown in FIGS. 1 to 5 are represented by like reference numerals. In the example embodiments of the present invention, the material layer is represented by an intermediate layer, and the cortex layer is represented by an outer layer, however the material layer is the same as the intermediate layer, and the cortex layer is the same as the outer layer.

[69] FIG. 6 is a perspective view of a pillow with a multi-layered structure according to a second example embodiment of the present invention. FIG. 7 is a cross-sectional view of the pillow with a multi-layered structure, taken along A-A line of FIG. 6. FIG. 8 is a side view of the pillow shown in FIG. 6.

[70] FIG. 9 is a longitudinal cross-sectional view of an intermediate layer of a pillow according to a third example embodiment of the present invention. FIG. 10 is a vertical cross-sectional view of the intermediate layer of the pillow according to the third example embodiment of the present invention.

[71] FIG. 11 is a cross-sectional view of a pillow with a multi-layered structure according to a fourth example embodiment of the present invention. FIGS. 12 (a) and 12 (b) are diagrams showing an example of pressure occurring around the pillow of FIG. 6.

[72] FIGS. 13 (a) and 13 (b) are diagrams showing a state where an intermediate layer of the pillow shown in FIG. 6 or 11 is used.

[73] FIGS. 14 (a) through 14 (f) are diagrams showing modifications of the pillow of FIG.

6. FIGS. 15 (a) through 15 (e) are cross-sectional views of modifications of the pillows of FIG. 14, in which a core is omitted.

[74] FIG. 6 is a perspective view of a pillow with a multi-layered structure according to a second example embodiment of the present invention. Like the pillow according to the first example embodiment of the present invention, the pillow 10 with a multi-layered structure basically includes a core 20, an intermediate layer 22, and an outer layer 24. The pillow 10 according to the second example embodiment of the present invention is different from the pillow according to the first example embodiment in the structures and features of the core 20, the intermediate layer 22, and the outer layer 24.

[75] When a user lays his/her head on the pillow, the core 20 supports the cervical vertebrae of the user.

[76] The intermediate layer 22 is formed to cover the core 20. When the head is laid on the pillow, the intermediate layer 22 supports the cervical vertebrae.

[77] The outer layer 24 includes a first support section 30a and a second support section 30b. The first support section 30a is formed to cover the intermediate layer 22 and supports the cervical vertebrae when the head is laid on the pillow. The second support section 30b is formed to extend from the first support section 30a, and supports the head when the head is laid on the pillow.

[78] In the pillow 10 with a multi-layered structure according to the second example embodiment, the intermediate layer 22 having the core 20 formed therein is included in the outer layer 24, and the shape of the pillow 10 is asymmetrical.

[79] The core 20 maintains the support structure of the pillow 10. The intermediate layer

22 includes a hollow portion 25 (shown in FIG. 7) which is formed between the outer layer 24 and the intermediate layer 22. The shape of the hollow portion 25 may be determined by a shape formed by an inner surface of the outer layer 24 and an inclined portion 22c adjacent to the outer boundary 22b of the intermediate layer 22. For example, the hollow portion 25 may be formed to have a trapezoidal cross-section.

[80] The outer layer 24 includes an opening 202 for reducing the stress generated when the head is laid on the pillow.

[81] The size of the pillow 10 may be set in such a range that the core 20, the intermediate layer 22, and the outer layer 24 can support the head and the cervical vertebrae with uniform pressure. For example, the height of the pillow 10 from the bottom may be set in such a range that the height of the first support section 30a is about two times larger than that of the second support section 30b. However, the length and height of the pillow 10 are not limited to these proportions, and it will be understood by those skilled in the art that the length and the height of the pillow 10 can be changed.

[82] The core 20 of the pillow 10 may be formed of a material selected from urethane, silicon, wood, and so on, to have a hardness similar to that of the arm bone. The intermediate layer 22 may be formed of a material selected from high-elasticity polyurethane foam, silicon foam, and so on. The outer layer 24 may be formed of low- elasticity polyurethane foam or latex foam such that a soft contact feeling can be maintained while pressure against the head and the cervical vertebrae is minimized.

[83] The intermediate layer 22 has lower hardness and elasticity than the core 20 but higher hardness and elasticity than the outer layer 22.

[84] Now, the core 20, the intermediate layer 22, and the outer layer 24 composing the pillow with a multi-layer structure according to the second example embodiment of the present invention will be described in more detail.

[85] FIG. 7 is a cross-sectional view of the pillow of FIG. 6. Referring to FIG. 7, the hollow portion 25 is formed between the intermediate layer 22 and the outer layer 24.

[86] The core 20 may have the hardness enough to maintain the structure of the cervical vertebrae from the head to the thoracic vertebra against the pressure applied when a human body lays his/her head on the pillow. Meanwhile, the synthetic bone may be replaced with another component. For example, the core 20 may be formed of another material having similar properties to bone, such as urethane, silicon, or wood. The core 20 is positioned to substantially coincide with a center of the curved cervical vertebrae, thereby maintaining the entire structure of the pillow 10. The core 20 keeps the cervical vertebrae in their normal posture. When the cervical vertebrae are crooked, the core 20 can correct the posture of the cervical vertebrae.

[87] The intermediate layer 22 serves to support the cervical vertebrae and the hardness and elasticity of the intermediate layer 22 is between the hardness and elasticity of the outer layer 24 and the hardness and elasticity of the core 20.

[88] The hollow portion 25 is an empty space formed inside the outer layer 24. The shape of the hollow portion 25 is determined by a shape formed by the inclined portion 22c adjacent to the outer boundary 22b of the intermediate layer 22. The air within the hollow portion 25 is ventilated through the outer layer 24.

[89] The outer layer 24 includes the first support section 30a disposed above the core 20 and the second support section 30b extending from the first support section 30a. The first support section 30a has a different shape from the second support section 30b. The first support section 30a has a circular shape which roughly coincides with the curvature of the cervical vertebrae, and the second support section 30b has a shape which roughly coincides with the curvature of the head (refer to FIG. 6).

[90] FIG. 8 is a side view of the pillow shown in FIG. 6.

[91] Referring to FIG. 8, the pillow includes at least one opening 202 formed in the longitudinal direction, in addition to the core 20, the intermediate layer 22, and the outer layer 24. The outer layer 24 has the first support section 30a, which has a horizontal length and height and surrounds the intermediate layer 22, and the second support section 30b extending from the first support section 30a. The first support section 30a has a different shape from the second support section 30b.

[92] The first support section 30a of the pillow 10 has a circular shape which roughly coincides with the curvature of the cervical vertebrae, and the second support section 30b has a shape which roughly coincides with the curvature of the head. The first and second support sections 30a and 30b distributes pressure caused by the weight of the cervical vertebrae and the head, thereby providing comfort to the head laid on the pillow 10.

[93] As described above, the outer layer 24 has at least one opening 202 formed along the longitudinal direction thereof. As shown in FIGS. 14 and 15, which will be described below, the opening 202 may be selectively provided. The opening 202 of the outer layer 24 serves to reduce stress caused by the head on the pillow.

[94] FIG. 9 is a longitudinal cross-sectional view of an intermediate layer of a pillow according to a third example embodiment of the present invention. FIG. 10 is a vertical cross-sectional view of the intermediate layer of the pillow according to the third example embodiment of the present invention.

[95] Referring to FIG. 9, an intermediate layer 22 of the pillow 10 according to the third embodiment of the present invention has one or more serrations 222 along the horizontal direction. Each of the serrations 222 forms a gap in the vertical direction. The serrations 222 may be formed in a portion of the intermediate layer 22 corresponding to the hollow portion 25. However, it will be appreciated by those skilled in the art that one or more serrations which form a gap in the vertical direction may be formed across the intermediate layer 22 along the horizontal direction, without being limited to the hollow portion of the intermediate layer 22.

[96] Referring to FIG. 10, one or more holes 224 are formed along the longitudinal direction of the pillow 10 according to the third example embodiment of the present invention. According to the construction of FIGS. 9 and 10, when a user lies on his/her back, the serrations 222 minimize the transmission of tensile stress, thereby enhancing comfort. Also, the holes 224 absorb shock when the head comes in contact with the pillow 10, and distribute compression stress when the user lies on his/her back. Furthermore, the holes 224 can enhance ventilation throughout sleep.

[97] The intermediate layer 22 has lower hardness and elasticity than the core 20 but higher hardness and elasticity than the outer layer 24. The intermediate layer 22 may be formed of an elastic material selected from high-elasticity polyurethane foam, silicon foam, and so on. When pressure caused by the weight of the cervical vertebrae is applied to the intermediate layer 22, the intermediate layer 22 can easily distribute the pressure to the plurality of serrations 222. Further, since the intermediate layer 22 is formed of an elastic material, the intermediate layer 22 provides elasticity to the head and the cervical vertebrae such that the shape of the cervical vertebrae can be maintained.

[98] FIG. 11 is a cross-sectional view of a pillow with a multi-layered structure according to a fourth example embodiment of the present invention. Referring to FIG. 11, the intermediate layer 22 and the outer layer 24 of the pillow 10 have substantially the same constructions as in the pillow shown in FIG. 6. However, in the pillow according to the fourth example embodiment, the core may be omitted.

[99] In the pillow with a multi-layered structure according to the fourth example embodiment of the present invention, the outer layer 24 includes a first support section 30a and a second support section 30b extending from the first support section 30b, like the outer layer 24 of the pillow shown in FIG. 6. The first support section 30a has a different shape from the second support section 30b. The outer layer 24 has at least one opening 202 formed along the longitudinal direction thereof. The first support section 30a has a circular shape which roughly coincides with the curvature of the cervical vertebrae, and the second support section 30b has a shape which roughly coincides with the curvature of the head. The first and second support sections 30a and 30b distribute pressure caused by the weight of the cervical vertebrae and the head, thereby providing comfort.

[100] Like the outer layer 24 of the pillow shown in FIG. 6, the outer layer 24 is formed of low-elasticity polyurethane foam or latex foam to provide a feeling of softness.

[101] FIGS. 12 (a) and 12 (b) are diagrams showing a state where the pillow of FIG. 6 is used. FIG. 12 (a) shows a state before the head is laid on the pillow 10, and FIG. 12 (b) shows an example of pressure occurring around the pillow 10 after the head is laid on the pillow 10.

[102] In FIGS. 12 (a) and 12 (b), it is assumed that the pillow 10 supports an interval d from a starting point A of a neck to the vertex B of a head, when the user lies on his/ her back. In this case, the intermediate layer 22 is positioned on the bottom of the outer layer 24 in the vicinity of the starting point A in the interval d such that the pillow 10 can support the normal curvature of the cervical vertebrae. Further, the intermediate layer 22 does not exist in the vicinity of the vertex B such that the intermediate layer 22 does not directly support the cervical vertebrae in the vicinity of the vertex B. Therefore, the normal curvature of the cervical vertebrae due to the biased center of gravity of the pillow is maintained. Accordingly, when the head is laid on the pillow, the center of gravity supported by the pillow moves toward the cervical vertebrae, which makes it possible to provide a posture correction effect.

[103] FIG. 12 (a) shows that before the user's head is laid on the pillow, the center of gravity of the pillow 10 is not biased. Therefore, uniform pressure is applied from the center of the pillow 10. However, FIG. 12 (b) shows that after the user's head is laid on the pillow, pressure around the pillow 10 is not crowded to one side, but is uniformly distributed across the entire region.

[104] FIGS. 13 (a) and 13 (b) are diagrams showing a state where the intermediate layer of the pillow 22 shown in FIG. 6 or 12 is used.

[105] According to the structure of the intermediate layer 22 shown in FIGS. 13 (a) and 13 (b), a hollow portion 25 is formed inside the outer layer 24, and the intermediate layer 22 has one or more serrations 222.

[106] When a user lays his/her head on the pillow, the pressure of the cervical vertebrae is distributed into the hollow portion 25 and the serrations 222 of the intermediate layer 22. Therefore, stress f is uniformly received by the center and the surroundings of the intermediate layer 22. Accordingly, the uniformity of pressure applied to the hollow portion 25 and the serrations 222 of the intermediate layer 22 can be ensured

[107] Therefore, since the pillow with a multi-layered structure according to the present invention has the core corresponding to bone of a human body, the entire structure of the pillow can be maintained, and the normal posture of the cervical vertebrae can be maintained throughout sleep. Further, since the pillow includes the intermediate layer having elasticity similar to that of muscle of a human body, the user can enjoy elasticity and comfort. Further, since the pillow includes the outer layer having softness similar to that of soft tissue and skin of a human body, the user can enjoy a soft feeling. Furthermore, since the heights of the respective layers of the pillow are differently set at predetermined intervals, the user can select and use an optimal portion of the pillow.

[108] FIGS. 14 (a) through 14 (f) are diagrams showing modifications of the pillow of FIG. 6. In the modifications, the construction of the outer layer 24 is modified. The construction will be described with reference to FIGS. 14 (a) through 14 (f).

[109] In the modifications, the outer layer 24, as a portion of the pillow 10, is fixed to the core 20 and the intermediate layer 22. However, the outer layer 24 can be replaced with a modifiable form of another construction.

[110] Hereinafter, the modifications will be described with reference to FIGS. 14 (a) through 14 (f).

[I l l] In the modification shown in FIG. 14 (a), the outer layer 24 does not have an opening 202, unlike the outer layer shown in FIG. 8.

[112] In the modification shown in FIG. 14 (b), the outer layer 24 includes one opening 202a formed at a position which corresponds to a position between the head and the cervical vertebrae.

[113] In the modification shown in FIG. 14 (c), the outer layer 24 includes one opening 202b formed at a position at which the head of a human body is supported.

[114] In the modification shown in FIG. 14 (d), the outer layer 24 does not include an opening 202b, and the intermediate layer 22 is covered by the outer layer 24.

[115] In the modification shown in FIG. 14 (e), the outer layer 24 does not include an opening 202, and the outer layer 24 coves the intermediate layer 22.

[116] In the modification shown in FIG. 14 (f), a portion of the outer layer 24 is simply divided at a portion at which the head of a human body is supported.

[117] According to the modifications shown in FIGS. 14 (a) through 14 (f), the outer layer 24 is formed of low-elasticity polyurethane foam, latex foam, or the like. Therefore, the pillow can provide softness similar to that of soft tissue and skin, and a comfortable portion of the pillow can be selected.

[118] In the modifications shown in FIGS. 14 (a) through 14 (f), the core is not an essential component and may be omitted.

[119] FIGS. 15 (a) through 15 (e) are cross-sectional views of modifications of the pillows shown in FIGS. 14 (a) through 14 (f).

[120] The modifications shown in FIGS. 15 (a) through 15 (e) have a basic structure in which the core 20 is omitted, and only the intermediate layer 22 and the outer layer 24 are provided. The outer layer 24 fixed to the intermediate layer 22 can be replaced with a modifiable form of another construction. [121] Hereinafter, the modifications shown in FIGS. 15 (a) through 15 (e) will be described. [122] In the modification shown in FIG. 15 (a), the outer layer 24 does not include an opening 202a, unlike the outer layer shown in FIG. 11. [123] In the modification shown in FIG. 15 (b), the outer layer 24 includes one opening

202a formed at a position between the head and the cervical vertebrae. [124] In the modification shown in FIG. 15 (c), the outer layer 24 includes one opening

202b formed at a position at which the head of a human body is supported. [125] In the modification shown in FIG. 15 (d), the outer layer 24 does not include an opening 202, and two layers which can be separated from each other in the vertical direction are coupled to each other. [126] In the modification shown in FIG. 15 (e), the outer layer 24 is simply divided at a portion at which the head is supported. [127] Referring to FIGS. 15 (a) through 15 (e), the outer layer 24 can be replaced with an elastic outer layer 24 which may include openings 202a and 202b formed in four directions (front, rear, left, right) of the pillow 10. [128] The operational effects of the modifications shown in FIGS. 15 (a) through 15 (f) are the same as those of the modifications shown in FIGS. 14 (a) through 14 (e). [129] FIG. 16 (a) is a perspective view of a pillow according to a fifth example embodiment of the present invention. FIGS. 16 (b) through 16 (d) are diagrams for explaining an air bag unit of FIG. 16 (a). [130] Referring to FIGS. 16 (a) through 16 (d), the pillow according to the fifth example embodiment of the present invention includes an intermediate layer 22 which is formed to extend from the core 20 toward a position at which the head of a human body is supported, unlike the above example embodiments. Therefore, the intermediate layer

22 can support both the head and the cervical vertebrae. [131] As shown in FIG. 17 (a), the air bag unit 29 includes an air bag 29a containing a relatively small amount of air, for example, lOOcc through 200cc, an injection section for injecting the air, and a delivery section 29c which is coupled to the injection section

29b to deliver the air, injected through the injection section 29b, to the air bag. [132] The injection section 29b may be implemented by an air pump. [133] The delivery section 29c may have a tube-like or a pipe-like structure of which one end is closed. The delivery section 29c also serves to fix the air bag 29a. As shown in a portion B of FIG. 17 (a), the other end portion of the delivery section 29c which is coupled to the injection section 29b is bent at 90 degrees such that the delivery section 29c can be fixed.

[134] FIGS. 18 (a) and 18 (b) are cross-sectional views of the middle portion of the pillow including the air bag, taken along line A-A'of FIG. 16 (d).

[135] As shown in FIGS. 16 (b) and 16 (c), the air bag 29a may be formed on the intermediate layer 22 which supports the cervical vertebrae and the head.

[136] The pillow may be implemented in such a manner that the injection section 29b and the delivery section 29c of the air bag unit 29 are housed in the intermediate layer 22, as shown in FIG. 16 (c). Alternatively, the delivery portion 29c of the air bag unit 29 may be housed in the intermediate layer 22 while a portion of the delivery section 29 and the injection section 29b are exposed to the outside of the pillow. When the delivery portion 29c of the air bag unit 29 is housed in the intermediate layer 22 and a portion of the delivery section 29 and the injection section 29b are exposed to the outside of the pillow, the user can adjust an amount of injected air by hand. Further, the pillow may further include a separate pocket which can house the injection section 29b.

[137] In the pillow with a multi-layered structure, which is comprised of a combination of different materials composing the core 20, the intermediate layer 22, and the outer layer 24, the air bag unit 29 serves to buffer a pressure difference at the boundary between the intermediate layer 22 and the outer layer 24, to enhance comfort. Since the pressure within the air bag 29a is constant everywhere, the air within the air bag 29a flows into a portion where a pressure difference occurs, thereby removing the pressure difference.

[138] Depending on the user's head and neck shape, the pattern of pressure applied to the respective pillow differ. Therefore, the most comfortable pillow shape depends on the user. However, as the air bag 29a containing a relatively small amount of air is included in the pillow with a multi-layered structure, the air within the air bag may flow in such a manner that the structure of the pillow can be changed in accordance with the user's head and neck shape, when the pillow is actually used as shown in FIGS. 18 (a) and (e). FIG. 18 (a) shows a case where a person with a straight neck lays his/her head on the pillow, and FIG. 18 (b) shows a case where a person having a normal neck lays his/her head on the pillow. When a head is laid on the pillow having the air bag 29a according to this example embodiment of the present invention, the shape of the pillow changes to match the shape of the neck.

[139] Further, as shown in FIG. 17 (b), the air bag 29a may be manufactured to have a shape that is fitted to the shape of the neck and head. Then, pressure can be distributed to as wide an area as possible to further enhance comfort.

[140] In a modification of the fifth example embodiment of the present invention, the air bag unit 29 may be implemented in such a manner that only the air bag 29a and the delivery section 29c are provided without the injection section 29b. In another modification of the fifth example embodiment of the present invention, the air bag unit 29 may be implemented with only the air bag 29a.

[141] FIG. 19 (a) is a conceptual diagram for explaining the structure of an arm pillow, and FIG. 19 (b) is a cross-sectional view of a pillow according to a seventh example embodiment of the present invention that has a structure corresponding to the arm pillow structure of FIG. 19 (a).

[142] Referring to FIG. 19 (b), the arm pillow shown in FIG. 19 (a) is embodied to design the intermediate layer 22 in a modified manner. To simulate the feeling of lying on one's side and putting one's head on one's arm, a region Ml or M3 of the intermediate layer 22 is designed to reflect the shape of the arm pillow when the user lies on his/her side and puts his/her head on his/her arm. To simulate the feeling of lying on one's back and putting one's head on one's arm, a region M2 of the intermediate layer 22 is designed to reflect the shape of the arm pillow when the user lies on his/her back and puts his/her head on his/her arm. The pillow designed in such a manner has a structure mimicking the arm of a human body and simulating the feeling of laying one's head in one's mother's arm.

[143] While example embodiments have been disclosed herein, it should be understood that other variations may be possible. Such variations are not to be regarded as a departure from the spirit and scope of example embodiments of the present application, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. Industrial Applicability

[144] According to the present invention, the pillow with a multi-layered structure provides stability and comfort by using the bone-like rigid core and the muscle-like elastic cortex layer. Therefore, it is possible to enhance the feeling of comfort provided by the pillow.

[145] Further, the pillow with a multi-layered structure according to example embodiments of the present invention includes the first portion which supports the cervical vertebrae of a user, and the second portion which supports the head of a user. Therefore, the pillow can provide a posture correction effect.

[146] Further, the pillow can provide comfort from the softness of the outer layer, which is similar to the softness of soft tissue and skin of a human body.

[147] Further, the heights of the respective layers are differently set at predetermined intervals. Therefore, when a head of a human body is laid on the pillow, two or more heights can be utilized.

[148] Further, the pillow with a multi-layered structure according to example embodiments of the present invention constantly maintains pillow's height and hardness, unlike many conventional pillows. Therefore, the muscles and ligaments of the head or cervical vertebrae can be properly relaxed by the pillow, and the posture of the cervical vertebrae can be normally maintained throughout sleep. Further, a good comfortable feeling can be provided. Furthermore, the air bag included in the pillow with a multi-layered structure buffers a pressure difference at the boundary between the intermediate layer and the outer layer of the pillow. The air bag can change the structure of the pillow in accordance with the shape of the neck, thereby enhancing comfort. The air bag may be manufactured to have a shape that is fitted to the shape of the neck and head. Therefore, the pressure of the human body can be distributed onto as wide an area as possible to enhance comfort.

Claims

[1] A pillow with a multi-layered structure, comprising: a core that is formed of a material having a first hardness and a first elasticity such that the core corresponds to a bone of a human body; a material layer that is formed on the core, and formed of a material having a second hardness lower than the first hardness and a second elasticity lower than the first elasticity such that the material layer corresponds to a muscle of the human body; and a cortex layer that is formed on the material layer, and formed of a material having a third hardness lower than the second hardness and a third elasticity lower than the second elasticity such that the cortex layer corresponds to a soft tissue and a skin of the human body.

[2] A pillow with a multi-layered structure, comprising: a core that supports the cervical vertebrae of a user, when the user lays the user's head on the pillow; an intermediate layer that is formed to cover the core and supports the cervical vertebrae of the user, when the user lays the user's head on the pillow; and an outer layer that includes a first support section which is formed to cover the intermediate layer and supports the cervical vertebrae of the user, when the user lays the user's head on the pillow, and a second support section which is formed to extend from the first support section and supports a head of the user, when the user lays the user's head on the pillow.

[3] The pillow according to claim 2, wherein the core is formed of a material having a first hardness and a first elasticity, the intermediate layer is formed of a material having a second hardness lower than the first hardness and a second elasticity lower than the first elasticity, and the outer layer is formed of a material having a third hardness lower than the second hardness and a third elasticity lower than the second elasticity.

[4] The pillow according to claim 2, wherein the core is formed of one selected from the group consisting of urethane, silicon, and wood, the intermediate layer is formed of one selected from the group consisting of high-elasticity polyurethane foam and silicon foam, and the outer layer is formed of one selected from the group consisting of low-elasticity polyurethane foam and low-elasticity latex foam.

[5] The pillow according to claim 2, wherein the intermediate layer has one or more serrations forming a gap in a first direction to distribute pressure applied by the user when the user lays the user's head on the pillow. [6] The pillow according to claim 2, wherein the intermediate layer includes one or more holes formed along a longitudinal direction of the intermediate layer. [7] The pillow according to claim 2, wherein the outer layer includes an opening for reducing stress caused by the user when the user lays the user's head on the pillow. [8] The pillow according to claim 2, wherein when the user lays the user's head on the pillow, a center of a gravity supported by the pillow moves toward the cervical vertebrae of the user. [9] The pillow according to claim 2 further comprising: a hollow portion formed between the outer layer and the intermediate layer, wherein the shape of the hollow portion is determined by a shape formed by an inner surface of the outer layer and an inclined portion adjacent to the outer boundary of the intermediate layer. [10] The pillow according to claim 2, wherein the intermediate layer supports both the cervical vertebrae and the head of the user when the user lays the user's head on the pillow. [11] The pillow according to claim 2, wherein the intermediate layer has a first region designed to reflect the shape of an arm pillow when a user lies on the user's side and puts the user's head on the user's arm, and a second region designed to reflect the shape of an arm pillow when a user lies on the user's back and puts the user's head on the user's arm. [12] The pillow according to claim 2 further comprising: an air bag formed between the outer layer and the intermediate layer to support both the cervical vertebrae and the head of the user. [13] The pillow according to claim 12, wherein the air bag has a shape that is fitted to the shape of the cervical vertebrae and the head of the user, in order to distribute pressure applied to the human body over a wide area. [14] A pillow comprising : an intermediate layer that supports the cervical vertebrae of a user when the user lays the user's head on the pillow; and an outer layer formed to cover the intermediate layer, the outer layer including a first support section that supports the cervical vertebrae of the user and a second support section that is formed to extend from the first support section and supports a head of the user when the user lays the user's head on the pillow.