Patent Application
20130298335
The present invention relates in general to the field of sleeping surfaces. In particular, the present invention relates to a support surface assembly for sleeping persons. More particularly, the present invention relates to an air-permeable support surface assembly to allow a person to breath naturally and without obstruction while sleeping thereon and to a method for tensioning the surface.
Sleep is considered to be a time of growth and rejuvenation for organisms. Teenagers and adults typically sleep between 6-8 hours per night, while children and the elderly often require more sleep and thus spend more time in bed. It is therefore important that the surface that one sleeps on, no matter what one's age, does not pose any risks for any health or physical harm.
One of the many aspects of infant care includes the position in which an infant should sleep. Based on current research, parents are advised to place a sleeping infant in a supine (face-up) position, as opposed to a prone (face-down) position, due to the possible risks involved with prone sleeping. These risks include suffocation, which may occur if air (oxygen) flow to the infant is obstructed. Such an incident is more likely when the infant is positioned in a manner wherein its mouth and nose are in close contact with or are enveloped by a soft mattress or a mattress cover. Similarly, in a prone position, the infant may breathe into a small unventilated space, so that it may inhale exhaled carbon dioxide for an extended period of time, which in a subset of infants can lead to asphyxiation and death.
Although the sleeping infant may be positioned in its crib or bed in a supine position, when the infant is strong enough to turn over by itself, it may change on its own to a prone position. In many cases, an infant may be strong enough to turn from a supine to prone position, but not the reverse. Thus, if an adult does not notice that the infant has turned over, the infant may remain in the prone position for an entire night.
It is therefore important that the surface upon which an infant sleeps is air-permeable to allow the infant to breathe naturally and fully without obstruction, even in a prone position.
The American Academy of Pediatrics [www.aap.org] discloses that a firm mattress is helpful in preventing sudden infant death syndrome (SIDS) and in promoting child development. There have been various attempts by the prior art to overcome to problems associated with sleeping infants; however, they each have drawbacks or difficulties of their own.
For example, U.S. Pat. No. 5,664,273 and U.S. Pat. No. 6,026,525 disclose different mattress assemblies for supporting a sleeping infant or child.
The present invention relates to a support surface assembly for a sleeping person. The assembly includes four corner elements, four elongated, rigid frame sections defining a rectangular perimeter of the support surface assembly, and an air-permeable layer suspended on the upper edge of the frame sections. A plurality of peripheral portions are attached to the air-permeable layer. Each of the frame sections is provided with an upper edge, inner wall, and outer wall. Two adjacent and substantially mutually perpendicular frame sections are pivotally connected to a common corner element.
Each peripheral portion of the air-permeable layer is received and secured by means of a pressure fit in a groove formed in the inner wall of a corresponding frame section. A frame contactable portion of the air-permeable layer is wrapped about the corresponding frame section upon application of a moment to each of the corresponding frame sections, tensioning the air-permeable layer and causing the corresponding frame sections to be coupled with two adjacent corner elements.
The peripheral portion is preferably attached to the air-permeable layer and includes a loop for receiving via an opening in the cover member a rod securable to walls of the groove.
The air-permeable layer is characterized by an ability to withstand fatigue tests of 500 pressing operations in which a load of 1 kg is loaded on a surface of 10 cm×10 cm with a speed of 50 mm/sec, without sagging and 2000 pressing operations in which the same load, surface and speed are applied, resulting in sagging of 2 mm at the point of impact.
In one aspect, the corner element has a convex outer wall and an arcuate inner wall both of which subtending an angle of approximately 90 degrees. Two straight interface elements extend between the outer wall and the inner wall at each terminal end thereof. Two apertures are bored in each of the interface elements by which a corresponding frame section is coupled with the corner element. The corner element may be provided with an interspace between the inner and outer walls through which attachment elements for immobilizing the corner element by means of a fixation device and for attachment to an underlying work surface pass.
In one aspect, the support surface assembly further includes a decorative shield contactable with, and securable to, the outer wall of the corner element. The outer wall of an adjacent frame section is substantially flush with the shield after being pivoted to an upright position.
In one aspect, the frame section has a cover member with a planar plate at each of its two longitudinal ends facing an adjacent corner element, an axle by which the frame section pivots and a spring biased pin protruding from the cover member for engaging the two apertures, respectively, bored in an adjacent interface element of the corner element.
In one aspect, the groove in which the peripheral portion of the air-permeable layer is received is a longitudinally extending groove that separates the inner wall of the frame section into an upper inner wall and a lower inner wall. The upper wall is oblique with respect to the outer wall such that the width of the upper edge which extends between the outer wall and upper inner wall is considerably less than the width of the bottom wall.
In one aspect, the frame section has a planar outer wall and a bottom wall substantially perpendicular to the outer wall and the lower inner wall, the bottom wall being provided with two opposed rounded portions extending to the outer wall and the lower inner wall, respectively.
In one aspect, vibratory motion of the air-permeable layer is transmitted to a movement sensor placed on a frame support by means of a vibration transmitter. The vibration transmitter includes an upper member in contact with an underside of the air-permeable layer, a lower member in contact with the movement sensor and coupled to the upper member, and spring means extending from the lower member to a surface of the upper member. The lower member oscillates in response to the vibratory motion, inducing a corresponding electrical signal by means of the movement sensor.
In one aspect, the support surface assembly further includes a plurality of pivotable legs for elevating one longitudinal end of the frame.
In one aspect, a final length of the air-permeable layer stretched over a distance between groove centers after pivoting the frame sections is 1-4% longer than the initial length before pivoting.
In one aspect, a ratio of fiber to area ratio of the air-permeable layer is between 40% and 60%, preferably between 45% and 55%.
The present invention is also directed to a method for tensioning an air-permeable layer that is suspended on a plurality of frame sections. The method includes the steps of:
In one aspect, two or more of the frame sections are concurrently pivoted.
In one aspect, a corner element is immobilized by coupling a fixation device thereto and attaching the fixation device to an underlying work surface.
In one aspect, each of the frame sections is pivoted by means of a corresponding arm assembly, the arm assembly comprising a plurality of differently oriented arms connected to a roller assembly in which are rotatably mounted three rollers that rollingly contact the outer wall, bottom wall, and inner wall, respectively, of the frame section.
In one aspect, a controller selectively controls the rate of pivoting of each of the arm assemblies to ensure that the sleeping surface of the air-permeable layer will be tensioned to a substantially uniform level.
According to a further aspect, the presently disclosed subject matter discloses a kit for constructing a support surface for a sleeping person. The kit comprises:
The air-permeable layer can be a screen printing mesh characterized by a fiber to area ratio of between 40% and 60%, preferably between 45% and 55% or by a mesh count of greater than 14.5/cm.
The air-permeable layer can be characterized by a tensile strength greater than 1000 N.
The air-permeable layer can be characterized by an ability to allow passage of gas therethrough such that, when a head box is placed with its open face on the air-permeable layer and a gas having an initial concentration of 7% of CO2 is flowed to the head box at a rate of 1.5 Liter/minute, after 5 minutes of the flow the concentration of CO2 in the gas in the head box does not exceed 1%.
The air-permeable layer can be characterized by an ability to withstand 500 pressing operations in which a load of 1 kg is loaded on a surface of 10 cm×10 cm with a speed of 50 mm/sec, without sagging and 2000 pressing operations in which the same load, surface and speed are applied, resulting in sagging of 2 mm at the point of impact.
The air-permeable layer can have a long and a short dimension and stretched so that in the long dimension it is under a greater tension than in the short dimension.
The air-permeable layer of the present disclosed subject matter can be characterized by different combinations of characteristics selected from the characteristics above.
The kit can further comprise a supplementary layer to be used with the support surface, the supplementary layer being made of air-permeable mesh fiber material which is softer the material of the air-permeable layer and which has a fiber to area ratio greater than the fiber to area ratio of the air-permeable layer, the supplementary layer being configured to cover at least a majority of the air-permeable layer.
The tensioning mechanism can comprise a pivoting axis about which the layer-edge engaging portion is configured for pivoting and which is fixedly disposed relative to the opposing frame section, and a rotatable portion for exerting a rotational force, at least indirectly, on the layer-edge engaging portion.
The rotatable portion can comprise at least a portion of the frame section different from the layer-edge engaging portion, which is pivotable about the pivoting axis when the force is exerted thereon, optionally at least indirectly by a user.
The first frame section or its tensioning mechanism can have a pre-tensioned position and pivotable therefrom to a tensioned position in which its layer-edge engaging portion is spaced from the opposition frame section to a distance shorter than that in the pre-tensioned position.
The kit can further comprise at least two corner elements attachable to the first frame section at two opposite ends thereof and configured to receive therein corresponding ends of the pivoting axis so as to allow pivoting of the frame section about the axis.
The ends of the frame section can be mis-aligned with the corners when in the pre-tensioned position and aligned with the corners and fixedly attached thereto in the tensioned position.
The at least one pair of parallel opposing frame sections can be two pairs of parallel opposing frame sections forming a rectangular perimeter of the frame. The at least one pair of opposing layer-edge portions can be two pairs of opposing layer-edge portions. Each of the frame sections can comprise the layer-edge engaging portion configured for fixedly engaging a corresponding layer-edge portion and being moved by its corresponding tensioning mechanism.
The layer-edge engaging portion can be a longitudinal groove formed in the frame section configured for engaging its corresponding layer-edge portion and for securing it therein by means of pressure fit.
Each of the layer-edge portions comprises a longitudinal loop configured for being received in the longitudinal grooves and to receive a securable rod therein, so as to be secured within the groove.
The tensioning mechanism can comprise fixing means configured for causing the tensioning mechanism leave the air-permeable layer at least partially tensioned.
The frame can further comprise at least one stabilizing member. The stabilizing member can be a transverse cross bar extending transversely between the opposite frame sections. The stabilizing member can also be a corner reinforcing element configured for connecting two adjacent frame sections.
According to a still further aspect, the presently disclosed subject matter discloses a method for constructing a support surface from components which constitute the kit describes above. The method comprises at least the following steps:
The method can further comprise a step of fixedly disposing the frame sections at a distance therebetween for forming at least a portion of a frame supporting the support surface.
The method can further comprise a step of pivoting the layer-edge engaging portion about the pivoting axis, thereby exerting a rotational force, at least indirectly on the layer-edge engaging portion by a rotatable portion.
The method can further comprise a step of pivoting the first frame section from its pre-tensioned position to a tensioned position, thereby spacing its layer-edge engaging portion from the opposition frame section to a distance shorter than that in the pre-tensioned position.
The method can further comprise a step of attaching two opposite ends of the first frame section to the corner elements by receiving therein corresponding ends of the pivoting axis so as to allow pivoting of the frame section about the axis.
According to a still further aspect, the presently disclosed subject matter discloses a support surface for a sleeping person. The support surface comprises:
The tensioning mechanism can comprise a pivoting axis about which the layer-edge engaging portion is configured for pivoting and which is fixedly disposed relative to the opposing frame section, and a rotatable portion for exerting a rotational force, at least indirectly, on the layer-edge engaging portion.
The rotatable portion can comprise at least a portion of the frame section different from the layer-edge engaging portion, which is pivotable about the pivoting axis when the force is exerted thereon, optionally at least indirectly by a user.
The first frame section can have a pre-tensioned position and pivotable therefrom to a tensioned position in which its layer-edge engaging portion is spaced from the opposition frame section to a distance shorter than that in the pre-tensioned position.
The support surface can further comprise at least two corner elements attachable to the first frame section at two opposite ends thereof and configured to receive therein corresponding ends of the pivoting axis so as to allow pivoting of the frame section about the axis.
The ends of the frame section can be mis-aligned with the corners when in the pre-tensioned position and aligned with the corners and fixedly attached thereto in the tensioned position.
The at least one pair of parallel opposing frame sections can be two pairs of parallel opposing frame sections forming a rectangular perimeter of the frame. The at least one pair of opposing layer-edge portions can be two pairs of opposing layer-edge portions, each of the frame sections comprises the layer-edge engaging portion configured for fixedly engaging a corresponding layer-edge portion and being moved by its corresponding tensioning mechanism.
The layer-edge engaging portion can be a longitudinal groove formed in the frame section configured for engaging its corresponding layer-edge portion and for securing it therein by means of pressure fit.
Each of the layer-edge portions can comprise a longitudinal loop configured for being received in the longitudinal grooves and to receive a securable rod therein, so as to be secured within the groove.
The tensioning mechanism can comprise fixing means configured for causing the tensioning mechanism leave the air-permeable layer at least partially tensioned.
According to a still further aspect, the presently disclosed subject matter discloses a support surface for a sleeping person The support surface comprises:
According to a still further aspect, the presently disclosed subject matter discloses a supplementary layer to be used with a support surface comprising a main mattress layer of a first air-permeable mesh fiber material having a first space-to-fiber ratio. The supplementary layer is made of second air-permeable mesh fiber material which is softer than said first material and which has a second fiber to area ratio greater than the first space-to-fiber ratio. The supplementary layer being configured to cover at least a majority of said main layer.
The supplementary layer can be made of polyester and can have a width of between 5 mm and 7 mm.
In order to understand the invention and to see how it can be carried out in practice, embodiments will now be described, by way of non-limiting examples only, with reference to the accompanying drawings, in which:
a schematically illustrates an exemplary mechanism for concurrently pivoting two arm assemblies of
b schematically illustrates a controller operable in conjunction with the mechanism of
a is an isometric view of a surface assembly having a pivotable leg for elevating one longitudinal end of the assembly.
b is an upper view of a surface assembly having a pivotable leg for elevating one longitudinal end of the assembly.
c is an upper view of a surface assembly having a pivotable leg of
Reference numerals of elements of the presently disclosed subject matter illustrated in
The average person spends between six to eight hours sleeping, out of a twenty-four hour day. Children and the elderly often spend even more time sleeping. It is therefore important that the construction of the mattress that one sleeps on is conducive to one's health. The present invention is concerned with providing a sleeping surface that can benefit people of all ages.
With regard to infants, it is important for an infant to be able to breathe naturally and without obstruction at all times while sleeping. Conventional mattresses are typically air-impermeable, which, therefore, blocks air flow to an infant who is sleeping in a face down position. This may cause the infant to stop breathing due to physical suffocation or by rebreathing of CO2 which may ultimately result in death. The present invention solves this problem by providing an air-permeable surface on which an infant may sleep, which enables air flow even when sleeping in a face down position. Additionally, the air-permeable surface of the present invention is constructed such that the risk of injury due to collision with a rigid frame is reduced to almost zero.
As shown in
Since frame sections 625 are concurrently pivoted, the entire sleeping surface of air-permeable layer 620, i.e. suspended between opposite frame sections, is tensioned to a substantially uniformly high level. For a mattress having dimensions in the range of 0.8-1.0 m width and 1.4-1.6 m length, the sleeping surface is tensioned to a level ranging from 700 kg to 800 kg and greater than 650 kg in the longer dimension of the mattress and from 400 kg to 500 kg and greater than 350 kg in the shorter dimension of the mattress. Those tensions withstand sagging for a period of at least three years during normal infant usage.
One suitable air-permeable layer 620 is a screen printing mesh made of polyester. Such a layer has a tensile strength of greater than 1000 N that can withstand a concentrated load of greater than 400 N without being punctured and is fatigue resistant during 2000 pressure applications of 10 N/100 cm2. An exemplary air-permeable layer is the PET 1000 15/40-200 W PW screenprinting mesh manufactured by Sefar AG, Thal, Switzerland made of polyester and having a warp and weft mesh count of greater than 14.5/cm and a fabric thickness of less than 375 microns.
The tensioning of the air-permeable layer is caused by the increase of the initial distance between groove centers to a final elongated distance when the frame sections 625 are flushed with the corners 615. The elongation is kept well within the material elastic range. For example, for a PET net elongation of the initial distance is preferably kept in the range of 1-4%.
As shown in
Longitudinal groove 645, in which the peripheral portion of air-permeable layer 620 is secured, is defined by an arcuate wall 647 subtending an angle of approximately 330 degrees, and by mutually parallel guide elements 648 and 649 extending from arcuate wall 647 to lower inner wall 634 and intermediate wall 635, respectively, for the insertion therebetween of the peripheral portion. Longitudinal groove 645 has an axis which is substantially parallel to outer wall 631. Intermediate wall 635 is adjacent to inner wall 636 and substantially parallel to outer wall 631. A reinforcing rib 639 extends from arcuate wall 647 to outer wall 631.
Cover member 650 connectable to frame section 625 is illustrated in
Each interface element 675, 676 extends radially outwardly from inner wall 672 and has a protruding portion 677 which protrudes from outer wall 674. An upper aperture 672a shown in
Corner element 615 may also have a bottom cover 681 attachable to abutment plates 671 and 673, or otherwise integrally formed with the corner element. Cover 681 has a recessed surface in which are formed large-holed apertures 688 and 689, by which an immobilizing device can be coupled, as will be described hereinafter. A decorative shield 690 contacting outer wall 674 may be attached to corner element 615 such that bottom surface 691 of the shield will be substantially coplanar with bottom cover 681 and each circumferential edge 693 of the shield will contact protruding portion 677 of the corner element.
An exemplary cover element may be made of nylon reinforced with glass fibers, e.g. PA6 and GF 40%, with its inner and outer walls having a thickness of 3-4 mm. The decorative shield may be made of ABA (Acrylonitrile Butadiene Styrene).
Peripheral portion 627 is illustrated in greater detail in
With reference also to
In
Frame section 625 is shown to be in a pre-tensioning position in
As shown in
With reference also to
Force applying element 712 has a vertical concave surface 721 whose bottom edge 723 borders apertures 717 and 718 as well as sidewall 704. A substantially planar portion 713 vertically extends from sidewall 704 to block element 707, being disposed inwardly from concave surface 721. Since block element 707 is massive, its weight is transmitted to engagement element 703 by means of force applying element 712, causing corner element 615 to be immobilized.
In order to pivot a frame section 625 and to thereby cause the air-permeable layer to be tensioned, a roller assembly 735 shown in
Roller assembly 735 comprises a U-shaped housing 737 in which are rotatably mounted three rollers 739. The three rollers 739 are adapted to rollingly contact outer wall 631 bottom wall 637, and upper inner wall 636 of frame section 625, respectively, to avoid tearing or severing of the air-permeable layer 620 when being tensioned. Each of the rollers 739 may be manually positioned to be in pressure contact with frame section 625, or alternatively, may be automatically positioned, e.g. by means of pneumatically actuated cylinders for displacing a roller to a desired position. The three rollers 739 are placed in sufficiently high pressure contact with frame section 625 such that a force applied to roller assembly 735 will cause frame section 625 to be correspondingly displaced without slip.
Three arms 746, 747 and 748 of arm assembly 741, which may be coplanar, are connected to base 738 of roller assembly housing 737 at different angles. Consequently, arm 746 is connected at region 756 in the vicinity of a first longitudinal end of base 738, arm 748 is connected at region 758 in the vicinity of a second longitudinal end of base 738, and arm 747 is connected at region 757 in the vicinity of an intermediate region of base 738 between regions 756 and 758, while the three arms are connected together at a distance from base 738. Thus a single moment applied to arm assembly 741 may be substantially evenly distributed to regions 756, 757 and 758 so that the air-permeable layer will be evenly tensioned when base 738 is pivoted.
Two or more frame sections 625 may be concurrently pivoted by means of the concurrent displacement of a corresponding number of arm assemblies 741.
One may design a concurrently pivoting mechanism. for the arm assemblies 741 of
Referring now to
The controller 870 may selectively control the operation of two drive units so that the corresponding arm assemblies will pivot at such a rate that the tension of the entire sleeping surface of the air-permeable layer will be tensioned to a substantially uniformly high level. A motion sensor in electrical communication with controller may be operatively connected to two or more pivot members. When a motion related parameter of a pivot member, e.g. angular velocity, is indicative that the tension of one region of the air-permeable layer will be greater than another region, the controller 870 commands one of the drive units to reduce the force applied to the corresponding piston.
Referring now to
Reference is now made to
The kit 100 can assembled by the user himself at home, or it can be assembled at the selling point. These both options do not require any special appliance, which provided to this kit one of its advantages over known in the art support assemblies with air-permeable layers.
The air-permeable layer 20 has two pairs of opposing layer-edge portions 11, 12, 13 and 14. The air-permeable layer 20 is configured to be stretched at least in a direction D1 between the layer-edge portions 12 and 13, and at least in a direction D2 between the layer-edge-portions 11 and 14. The stretching of the air-permeable layer 20 is configured to provide a tensioned layer which forms a main upper portion of the support surface 10. The support surface is constructed in such a way that enables to stretch and elongate the air-permeable layer 20 while its material is kept in its elastic range. For example, an elongation of the initial distance can be preferably kept in the range of 1-4%, at least in the directions D1 and D2.
The opposing frame sections 30, 32, 34 and 36 are fixedly disposable at a distance therebetween to define and to form together with the corner elements 22, 24, 26 and 28 a rectangular perimeter of a frame 15 (shown in
Each of the frame sections 30, 32, 34 and 36 comprises a layer-edge engaging portion 31, 33, 35 and 37, respectively. These layer-edge engaging portion are longitudinal grooves which are formed within their respective frame sections and configured for engaging their respective layer-edge portions for securing them therein by means of pressure fit. The layer-edge engaging portions 31, 33, 35 and 37 are configured to fixedly receive and secure the layer-edge portions 11, 12, 13 and 14 as follows: the layer-edge portion 11 is receivable within the layer-edge engaging portion 35, the layer-edge portion 12 is receivable within the layer-edge engaging portion 31, the layer-edge portion 13 is receivable within the layer-edge engaging portion 33 and the layer-edge portion 14 is receivable within the layer-edge engaging portion 37.
Each of the layer-edge portions is formed as a longitudinal loop which is configured to tightly receive a securable rod therein, via a side opening of the loop, following placement of the layer-edge portion in its corresponding layer-edge engaging portion. By insertion of the securable rods 16, 17, 18, and 19 in the loops of each layer-edge portion 11, 12, 13 and 14, respectively, while the layer-edge portions are received in their corresponding layer-edge engaging portions, the air-permeable layer can be fixedly secured to the frame portions 30, 32, 34 and 36 and thereby to the frame 15. At this stage, the air-permeable layer 20 is still not tensioned.
Each of the frame sections 30, 32, 34 and 36 is integrated with a corresponding tensioning mechanism 60, 62, 64, and 66. Each of the tensioning mechanisms 60, 62, 64, and 66 is configured for moving its corresponding layer-edge engaging portion 31, 33, 35 and 37 respectively together with the layer-edge portions 12, 13, 11 and 14 mounted thereto. During the assembly of the support surface 10, each layer-edge engaging portion is configured to pivotally move relative to an opposing frame section in order to at least partially tension the air-permeable layer 20 between the frame section of the layer-edge engaging portion and the opposing frame section.
The air-permeable layer 20 which is configured to be suspended and stretched or tensioned on the frame 15 of the support surface can have the same characteristics of the air-permeable layer described above. For example, one suitable air-permeable layer 20 is a screen printing mesh made of polyester. Such an air-permeable layer has a tensile strength of greater than 1000 N that can withstand a concentrated load of greater than 400 N without being punctured and is fatigue resistant during 2000 pressure applications of 10 N/100 cm2. An exemplary air-permeable layer is the PET 1000 15/40-200 W PW screenprinting mesh manufactured by Sefar AG, Thal, Switzerland made of polyester and having a warp and weft mesh count of greater than 14.5/cm and a fabric thickness of less than 375 microns.
Reference is now made to
In
In order to fix a frame section and its tensioning mechanism in its tension position to a respective corner element, each frame section comprises a fixing mechanism at each end element thereof.
Reference is now made to
As shown in
As shown in
As shown in
Reference is now made to
Several experiments were conducted using the support surface assembly of the present invention to determine the effectiveness of the invention with regard to the health benefits as described herein above.
This experiment was performed to determine the amount of dust mites that the support surface assembly of the present invention retains in comparison to a conventional mattress.
Dermatophagoides farinae (house dust mites) were cultured in a laboratory using a mixture of horse dander/medical yeast (2:1) at a temperature of 25±1° C. 75±5 relative humidity.
Three support surface assemblies of the present invention, each with a netting of 200 micron (20×20×6×2.8 cm), with 15 strings per cm and 48% open space, were tested and compared with a control (conventional) mattress, the core of which was a polymeric sponge covered with a tissue composed of 50% cotton and 50% polyester (22×22×8 cm), for the survival of mites under optimal environmental conditions. 0.01 mg of mites taken directly from the colony (without medium) (ca. 250-300 mites) and 40 mg of medium were evenly distributed over the entire surface of the support surface assemblies and mattress. Thereafter, the support surface assembly and mattresses were placed in an incubator (24° C. and 70-80% relative humidity). The viability of the mites was examined under a stereo-microscope after 2, 4 and 7 days. On day 7, the support surface assemblies were rinsed thoroughly with distilled water, and thereafter were examined under the stereo-microscope for any remaining mites. Mites were removed from the control mattress surface by shaking it over a container with water. Adhesive bands were glued on the surface of each mattress and the few remaining mites were collected and counted as well. The water with mites and medium from all four support surface assemblies and mattresses was filtered separately through several white filter papers (Schleicher & Schuell, 604, 7 cm diameter), and the number of live mites was counted under a stereo-microscope (5×).
The results of this experiment, showing the mite survival during the two days of experiment are displayed in Table 1, in
The few mites seen on the support surface assemblies were mainly concentrated at the edges of the mattress where the food and mites could survive between the wood and netting. The distance between fibers was large enough to prevent mites and medium from remaining on the surface. On the control mattress, mites were apparently behaving normally (laying eggs, copulating, eating). 30 times fewer mites could be found on the support surface assembly of the present invention than on the control mattress after 2 days of experimentation.
An additional experiment has compared ventilation properties of nets having different space to fiber ratios. This experiment was done in a hospital pulmonary laboratory, and an AirNettress® mattress of Lizron, The Child Development Company, Pardes-Hana, Israel, was used. The mattress is made of a polyester net (Sefar AG Filtration Solutions, Heiden, Switzerland) which is stretched over a wooden or aluminum frame. The net was made of 200 micron diameter fibers at a density of 15 fibers/cm, which attains a space to fiber ratio of approximately 1:1 (48%-fiber to area ratio), as well as nets having lower fiber to area ratios, 43%, 34% and 25%. A head box was placed with its open face on the mattress and connected with tubing to a gas reservoir filled with 7% CO2. The 7% CO2 mixture flowed into the head box at a rate of 1.5 Liter/minute (L/m). The rate of CO2 accumulation in the head box was measured at 10 second intervals for at least 5 minutes. The nets with fiber to area ratios of 43% and 48% exhibited significantly lower tendencies towards CO2 accumulation (under 1% CO2) than the nets with fiber to area ratios of 34% and 25%, (over 1.5% CO2), as shown in
To conclude, significant rebreathing of CO2 may be prevented by use of a netted surface with a fiber to area ratio of above 40%. Note that CO2 levels below 1% are considered safe environmental conditions according to NIOSH guidelines, DHHS Publication No. 76-194, august 1976.
The Standards Institution of Israel, Tel Aviv, conducted several fatigue tests to determine various parameters of the air-permeable layer. The sample that was tested had a thickness of 200 microns, a warp and weft mesh count of 15.0/cm. After 500 pressing operations, the sample was shown not to sag at all. After 1000 pressing operations, the sample was shown to slightly sag. After 2000 pressing operations, the sample was shown to sag 2 mm at the point of impact. In all these pressing operations, a load of 1 kg was loaded on a surface of 10 cm×10 cm with a speed of 50 mm/sec,
The tensile strength of the sample was tested. The sample was shown to have a lengthwise tensile strength of 1374 N, a widthwise tensile strength of 1031 N, a lengthwise elongation of 21%, and a widthwise elongation of 34%.
The laboratory division of Sefar AG, Thal, Switzerland, conducted an elasticity test on a sample of PET 1000 15-200 W PW screenprinting mesh. The sample that was tested had a thickness of 200 microns, a warp and weft mesh count of 15.0/cm.
The sample was overnight and then during the daytime was not tensioned. The tension of the sample was measured at night and during the daytime. The test was repeated three times. Here are the results:
The Japan Food Hygiene Association, Tokyo, conduction various tests on a white UX-SCREEN. The sample was shown to pass the material test with respect to cadmium and lead, the dissolution test with respect to heavy metals, consumption of potassium permanganate, antimony and germanium, and the residue on evaporation after dissolution test with the solvents of n-heptane, 20% ethanol, water, and 4% acetic acid.
The experimental results show that the present invention provides a safe support surface assembly for sleeping thereon, particularly for infants and those suffering from allergies, and enables effortless breathing through it.
While some embodiments of the invention have been described by way of illustration, it will be apparent that the invention can be carried into practice with many modifications, variations and adaptations, and with the use of numerous equivalents or alternative solutions that are within the scope of persons skilled in the art, without departing from the spirit of the invention or exceeding the scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 13009871 | Jan 2011 | US | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IL2012/050015 | 1/19/2012 | WO | 00 | 7/19/2013 |
