Valveless flotation device
The valveless flotation device uses the pressurized gas container as the flotation chamber, actuated by a simple slot mechanism, addressing the complexity and bulkiness of traditional devices, ensuring reliable inflation for diverse users.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SEA ARK TECH LTD
- Filing Date
- 2026-01-15
- Publication Date
- 2026-07-23
Smart Images
Figure IL2026050049_23072026_PF_FP_ABST
Abstract
Description
[0001] VALVELESS FLOTATION DEVICE
[0002] FIELD
[0003] The present disclosure describes technology related to the field of devices for providing flotation to persons or objects in water, using inflated balloon-like structures, especially for use where a low cost construction is desired, and a simple mode of actuation is required.
[0004] BACKGROUND
[0005] Drowning is a major cause of death worldwide, claiming the lives of more than 300,000 people every year. Many of the drowning events occur in natural waters such as the sea and lakes in the absence of a supervising life guard, and many would have been preventable by use of a personal flotation device. The currently most commonly used inflation devices are based on a charge of pressurized gas which is released on actuation, into an inflatable flotation chamber. One common example of such devices are the life-vests or lifejackets used in aircraft, which are intended to be inflated in times of emergency by a gas cylinder, generally containing compressed carbon dioxide, or, if the compressed gas inflation fails, by the breath of the wearer.
[0006] Earlier models of such flotation devices used metallic cylinders to contain the high pressure flotation gas, a flotation chamber into which the gas can expand, and a valve mechanism such as a hand-operated, sharp pin, to pierce the high pressure gas container to allow the flotation chamber to inflate. Such earlier models used gases requiring compressing at normal environmental temperatures, to a high pressure of many tens of bar to maintain the required gas charge within its pressurized container, whether in its liquid phase or in a gas phase. The gas pressure may even reach a pressure of 100 bar at high environmental temperatures, such a 60°C, such a temperature being easily reached, for instance, in a closed car sitting in a sunny location. Two of such gases are air or carbon dioxide, especially the latter, which was a widely used gas in these earlier models, and is still in common use today. More recent models of such flotation devices use gases which maintain their liquid phase at normal environmental temperatures, and even up to temperatures expected when the device undergoes direct exposure to the sun, such as 60°C or more, at much lower pressurizations, typically of the order of 10 bar or so. Some such gases are used in the devices described in International Patent Application WO 2020 / 208636 for “Emergency Flotation Device using Compressed Gas”,having common inventors with the present application. This enables the use of a pressurized gas container made of a much lighter material, such as plastic materials, which can also be thinner, but still requires some sort of valve to contain the gas in the pressurized gas container until released into the flotation chamber when the device is actuated.
[0007] Because of the lower pressures involved, the above-referenced application also simplifies the valve used to contain the pressurized gas in its container, before its release by actuation of the device. The “valve” in that publication is simplified by use of a containing cap rather than a conventional valve, to keep the compressed gas in the pressurized gas container. Manually separating or dislodging the element that holds the cap in place, actuates the flotation device by allowing the combatively low pressure of the gas itself to push aside the cap and to allow the gas to inflate the flotation chamber.
[0008] The disclosures of each of the publications mentioned in this section and in other sections of the specification, are hereby incorporated by reference, each in its entirety.
[0009] SUMMARY
[0010] The present disclosure attempts to provide novel devices and methods that overcome at least some of the disadvantages of prior art systems and methods. The present disclosure describes new exemplary systems for providing emergency flotation, in which the structure is simplified by utilizing the pressurized gas container to also act as the flotation chamber. Expressed conversely but with the same effect, the flotation chamber is utilized to also act as the pressurized gas container. Either nomenclature is used in this disclosure to describe the devices, neither being intended to be limiting.
[0011] The devices of the present disclosure achieve this by having the pressurized gas container filled with the required volume of gas, either in the liquid phase or still in the gaseous phase, which will ultimately enable the gas charge to provide the needed flotation when the pressurized gas container is allowed to inflate. The pressurized gas container then behaves also as the flotation chamber. This inflation is initially prevented by virtue of the gas-charged pressurized gas container being enclosed in an outer envelope material, or an alternative outer element, binding the pressurized gas container and preventing it from expanding. The outer envelope or outer binding element must be selected to be sufficiently strong to withstand the forces generated by the pressurized gas. This outer envelope may also be referred to hereinafter as the enclosure or outer enclosure or outer binding element, The enclosure has anopening mechanism which will be described hereinbelow, actuated by a simple hand or finger operated procedure performed manually by a swimmer in distress The devices can also be actuated automatically, when immersed in water or when reaching a predetermined pressure, as is further described in the above referenced commonly owned International Patent Application WO 2020 / 208636 for “Emergency Flotation Device using Compressed Gas”. The opening mechanism allows the pressurized flotation chamber to break out of the constraints of the enclosure or the binding element as a result of this simple hand action, and to inflate, thereby providing the swimmer with life-saving support.
[0012] In a first method of implementing the operation of the emergency flotation device, the enclosure is a bag structure enveloping the pressurized gas container, and the opening of the enclosure is enabled by constructing it with a slot-like opening, held closed by a closure structure having a predetermined resistance to opening, sufficient to contain the forces which the pressurized gas exerts from within the pressurized gas container. The slot-like opening should be divided into two parts - the major part being held closed by a closure mechanism having a structure sufficiently strong that it would prevent the gas in the pressurized gas container from expanding if it covered essentially the entire length of the slot, and a minor part completing the closure by a closure element, easily actuated by a hand or finger action, and covering that part of the slot not held closed by the closure mechanism. Since the minor part of the slot is short, the forces exerted by the pressurized gas are small, and a simple easily removable element is sufficient for use in closing the minor part of the slot. The opening of the entire slot is initiated by releasing the closure element, which is operative to hold closed that minor part of the slot not held closed by the closure mechanism. Once an initial opening is generated at the minor part of the slot by actuating the release of the closure element, the force generated by the pressure of the gas in the pressurized gas container is then sufficient to break the constraining hold of the closure mechanism, such that the entire length of the slotlike opening then opens, starting at the end adjacent to the minor part of the slot which was initially held closed by the closure element. This enables the pressurized gas container to break out of the fully opened slot of the outer envelope, and to self-inflate to provide the flotation support required by the swimmer. The pressurized gas container can thus expand externally through the slot, the container now acting as the flotation chamber. So long as the closure element is not released, the flexible enclosure itself and the closure structure holding the slot closed, have sufficient strength to contain the forces which the pressurized gas exerts from within the pressurized gas container. The mechanical strength provided by this closurestructure, regardless of what form it takes, should be calculated to resist the outward forces exerted by the pressurized gas container. The device thus eliminates the need for a separate pressurized gas container and flotation chamber, with a valve between them. The entire flotation implementation of the device thus consists only of the pressurized gas container and an enclosure envelope having a slot, mostly closed by a closure mechanism, and including a hand or finger operated closure element closing the minor remaining part of the slot, for initiating its opening. Parts and components required to actuate previously available flotation devices, such as a valve at the gas exit of the pressurized gas container, have thus been completely eliminated, thereby providing a simpler construction than previously described flotation devices.
[0013] There are many optional closure mechanisms which can be used in order to hold the major part of the slot-like opening in its closed position. One simple and reliable implementation of the openable slot uses a zipper mechanism without the slider, which closes a major part of the length of the slot, leaving the minor part of the slot devoid of the zipper mechanism, but held closed by the manually actuated closure element. This manual actuated closure element may be any form of closure device, such as a tape on that part of the slot not held closed by the zipper closure mechanism. When the manually operated closure element is released, such as by pulling off the tape from the minor part of the slot, the minor part of the slot is free to open, and the pressure of the pressurized gas container applies a force to the now partially opened slot, and the closure mechanism covering the major part of the slot can no longer restrain the outward force of the pressurized gas container on the closed part of the slot. A zipper closure mechanism cannot generally open simultaneously along the whole of its length, since the two sides are firmly held together by an array of interlocking teeth, and would need a very high force to tear the sides apart. A conventional zipper is opened by passage of the slider, which bends the zipper elements at an angle to enable the teeth to disengage, rather than to be tom off. In the presently described zipper mechanism, a slider is not used, but the bending of the zipper elements to enable disengagement, is generated by allowing the unattached end of the zipper train to be separated by the action of the expanding pressurized gas container in the opened minor part of the slot, bending the ends apart, until the zipper opens along the complete length of the slot, starting from the region adjacent to the minor part of the slot. The pressurized gas container thus expands through the whole length of the now open slot, until fully inflated.This entire opening mechanism can thus be concisely summarized as having a zipper mechanism with a short section with a significantly weaker closure ability than that of the remainder of the zipper mechanism, and in that short section, the internal force exerted by the pressurized gas container is not constrained by the zipper mechanism but by a manually or automatically released attachment. Release of this attachment enables the pressurized gas container to break out at that section, and consequently, to force open the entire length of the zipper mechanism.
[0014] The forces needed to tear the zipper teeth apart are much larger than the forces exerted by internal pressure on the enclosure. The minor, teethless part of the slot, is typically held together by a tape, and though able to withstand a much lower level of force than the zipper mechanism itself, it is able to withstand the internal pressure of the pressurized gas container since the internal pressure is acting only on a short length of the closure. Once the tape is removed, the zipper teeth are angled to a disengaging position by the force of the pressurized gas container breaking through the now open gap, and as a result, the entire zipper opens sequentially. The length of the minor part of the slot, compared to that of the major toothed part of the slot is determined by a compromise between the resistance of the minor part closure element to the force of the compressed gas attempting to push it open, and the need to enable the actuating method to be readily performed with a minimum of force.
[0015] However, one important feature of the described device arises from the conflict between the pressure of the gas in the compressed gas container, and the ability of such an outer envelope with an openable slot to withstand the forces exerted by the pressurized gas container, which are attempting to burst the enclosing envelope, or to push the slot open. Previously used high pressure gases such as carbon dioxide, if used in the presently described device with the same quantity of gas required to provide buoyancy for a large person, and with that quantity of gas compressed into the same volume as that of those prior art devices, would require an outer envelope and slot having force restraining properties so high that it would not allow the device to be implemented in a conveniently usable and flexible form, and actuated by a simple manual motion, even of a child. In the first place, the outer envelope would have to be capable of readily withstanding the high pressure of the compressed gas in the flotation chamber, which can reach up to 100 bar. Secondly, the openable slot would require a much sturdier structure, and would be difficult to be actuated by a simple hand pulling action, such as is achievable by the removal of a tape.One effective solution to that problem is indeed provided by the use of the low pressure gases previously described in WO 2020 / 208636, such that the pressure in the uninflated pressurized gas container is sufficiently low that a comparatively thin flexible outer containing enclosure can be used, and an openable slot such as a zipper can be used, which can withstand the low pressure of the pressurized gas charge, and yet still can be readily actuated using the expansion of the gas pushing apart the two arrays of meshed zipper teeth. The simple operability of the devices of the present disclosure, is most practically solved by the use of such low pressure gases.
[0016] The partial length zipper is only one example of a slot-like opening which can withstand the forces arising from the pressure of the compressed gases used, and yet can be fully pushed open when initially opened to a predetermined extent. The flotation devices of the present implementation of this application are not intended to be limited to such a zipper embodiment, but could include any such a closure mechanism for opening a slot which withstands the pressure of the compressed gas charge in the flotation chamber, but which readily fully opens from the pressure of the gas, when manually opened to a predetermined extent. Other examples of controlling the closure and opening of such a slot may include components such as a Ziploc® mechanism, or a Velcro® hook-and-loop connector or a row of snap fasteners (press studs), or an array of hook and eye connectors, or a simple adhesive bond executed either by an adhesive tape or by sticking the edges of the slot together using an adhesive compound. Obviously, for use in the stressed levels required by the presently described devices, specially engineered examples of these domestically used fasteners would need to be used to withstand the force levels generated in such a device, but the closing mechanism would have the same operating principle as that of domestically usable slot closure arrangements.
[0017] It is to be understood that the use of the term closure “mechanism” is not intended to limit the closure method to the use of a pure mechanical device, but the term “mechanical” is intended to cover any arrangement where the opening is achieved by any kind of motion of the parts. A second implementation of the devices of the present disclosure, enables the foregoing of the need for an outer bag-like envelope, to completely or almost completely contain the pressurized gas container. This second implementation achieves the containment of the pressurized gas container by using a length of cord, or a length of a tape, or a rope or a net, bound around parts of the outward walls of the pressurized gas container, to keep the outwardly directed forces of the compressed gas constrained, such that the pressurized gascontainer cannot expand outwardly. Such a binding method can generally be readily released by use of a bow, or a knot or another tying method, which is readily released by using a simple hand or finger motion. Many such bows, ties or knots are known, especially in the nautical environment, where ropes and ties are widely used. An even more familiar instance is in the methods used to tie shoe laces, by which, the shoe lace closing a shoe is able to resist a high force attempting to open it from the inside, and yet can be readily opened by simply pulling on the free end of a properly formed “bow” in the lace, thereby releasing an outward force many times that required to release the bow. In use, such a rope or cord or tape would be wound a number of times around the pressurized gas container, with a spacing between the turns, and the ends attached using such a readily releasable tying method. When the device is actuated by releasing the tied ends, the rope or cord or tape would simply unwind from around the pressurized gas container, sliding around the surface of the pressurized gas container as it expands and provides the needed flotation to the user. In a similar manner, a net could be draped around the pressurized gas container, and held in place by a similar readily released tie in cord holding the free ends of the net together.
[0018] Both of the above described implementations optimally use new low pressure refrigeration gases, which remain in the liquid phase at up to high environmental temperatures, and therefore do not require the use of high pressure cylinders to contain them when compressed. However, the present devices could also be enabled with the previously used high pressure gases, by a change in the quantity of gas used in the pressurized gas container. In prior art devices using gases such as air or carbon dioxide, a metallic valved cylinder is needed to contain the high pressure gas, and such a metallic cylinder is an impediment to miniaturization, or even just to the convenience of storing or wearing the device. In order to keep the cylinder as small as possible, the gas is contained in the cylinder at a very high pressure, of many tens of bar or even 100 bar, and when exposed to heat, an even higher pressure.
[0019] However, since the pressurized gas container of the devices of the present application is used as the flotation chamber, it must necessarily be a flexible container. However, when volume minimization is less of an issue, then, by using a larger volume flexible compressed gas container, it is possible to store the required volume of compressed gas at a lower pressure, while still providing the same volume required for the flotation force. For an ideal gas, the volume of the gas is inversely proportional to it pressure. Both air and carbon dioxide have thermodynamic properties such that they are both in their gaseous state at room temperature,or sea temperature. The ideal gas law is therefore directly applicable to both of those gases, or indeed to any other high pressure gas historically used in cylinder-equipped flotation devices. The volume required of the flexible pressurized gas container is thus dependent on: (i) the final volume of the flotation chamber required for the flotation device considered, i.e. whether for a child, or for an adult, or for an overweight adult, etc., and
[0020] (ii) the level of pressure the flexible pressurized gas container and its surrounding envelope are designed to withstand. This translates into the multiplication factor to be used for the pressurized gas, over the gas pressure intended in the fully inflated flotation chamber, that intended pressure generally being 1 bar or slightly above. The extent to which the material of the flotation chamber can stretch, will determine how close to atmospheric pressure the inflated gas will come, and this extent is not intended to be a limitation of the invention, but merely an outcome of the construction materials.
[0021] As an example, for a 5 liter flotation volume at atmospheric pressure (5 liters being sufficient to provide support to a large adult), and a gas container volume of 500cc, which is a manageable volume for a flexible pressurized gas container, the pressure of a compressed gas such as air or carbon dioxide would need to be no more than 10 bar. This is a much more handleable pressure than the prior art carbon dioxide filled cylinders, whose pressure ran into many tens of bar. Similarly, if it is decided that the flotation device design is such that the volume of the flexile pressurized gas container should not exceed 250 ml, the pressure of a compressed gas such as air or carbon dioxide, would need to be approximately 20 bar. In any of these cases, the pressure at which the pressurized gas container and its constraining enclosure should withstand should also include the increase expected when the device is exposed to high environmental temperatures, such as 60°C or even more. The values given are not intended to be limiting values, but are merely examples to show a typical implementation using prior art conventional gases, but in the valveless device of the present disclosure.
[0022] Though the application is described in terms of use by a person in water, since this is the most usual use for which the presently described emergency flotation device would be used, it is to be understood that the device can be used for providing flotation support for any object that needs to be prevented from sinking in water, such as a lift raft, or an airborne article dropped into the sea for delivery there in such need. The latter examples could involve an automatic actuation system for enabling inflation actuation on contact with the water, such devices being known in the art.There is thus provided in accordance with an exemplary implementation of the devices described in this disclosure, a device for providing flotation support to a person in water, comprising:
[0023] (i) a sealed inflatable flexible pressurized gas container, containing a charge of a gas that, when allowed to expand, is sufficient to provide flotation support to the person in water, and (ii) an outer constraining part, encircling the pressurized gas container, and having restraining strength sufficient to hinder the outward force of the pressurized gas charge from inflating the compressed gas container,
[0024] wherein the outer constraining part has an actuation release mechanism, such that when actuated, the resistance of the outer constraining part is reduced to an extent such that the outward force of the pressurized gas charge overcomes the resistance of the outer constraining part, enabling the gas charge to expand and to inflate the compressed gas container, to provide flotation support to the person in the water.
[0025] In such a device, the outer constraining part may comprise an outer enclosure comprising a closure slot having a major part held closed by a closing mechanism and a minor part held closed by a separate closure element including the actuation release mechanism for releasing the closure,
[0026] wherein the closing mechanism has a resistance to opening at a level which withstands the outward force of the pressurized gas charge only when the minor part of the closure slot is held closed.
[0027] In the above mentioned devices, when the actuation release mechanism frees the closure element, the outward force of the pressurized gas within the pressurized gas container should be sufficient to open a major part of the closure slot, and to enable the pressurized gas container to inflate outside of the outer enclosure. The major part and the minor part of the closure slot should have different mechanisms, the major part having a resistance to opening per unit length, higher than the resistance to opening per unit length of the minor part.
[0028] Furthermore, the ratio between the lengths of the major and the minor parts of the closure slot is determined by the force exerted by the pressure of the gas charge in the pressurized gas container at its maximum rated temperature, and the resistance to opening per unit length of the minor part of the closure slot.
[0029] The resistance to opening of the minor part of the closure slot may be sufficiently small that the actuation element can be operable by a hand or finger movement. Alternatively, theactuation element can be operable automatically when the device is exposed to water having a predetermined depth.
[0030] Additionally, so long as the major part of the closure slot remains closed and the actuation mechanism is not released, the gas container is prevented from exiting the flexible outer enclosure.
[0031] In any of the above described implementations, at least the major part of the closing slot may comprise any one of a zipper mechanism, a Velcro section, a Ziploc section, a press stud section, or an adhesive bond. In the zipper option of the major part of the closing slot, the release of the minor part of the closing slot should enable the zipper mechanism to open along its length, starting from the end or ends of the zipper mechanism adjacent to the minor part of the closing slot. The minor part of the closing slot may comprise any of a hook and eye connection between the two opposite sides of the slot, an adhesive band connecting the two sides of the slot, or an adhesive bond connecting the two sides of the slot. The actuation element should be attached to the minor part of the closure slot.
[0032] In accordance with a further exemplary implementation of the devices described in this disclosure, the outer constraining part encircling the pressurized gas container may comprise a cord or a net, wherein the manually actuated release mechanism is a releasable knot in the cord or net, the release of the knot or bow enabling the pressurized gas container to expand such that the gas charge inflates the pressurized gas container.
[0033] In such a device, the releasable knot may be released by manual pulling on a free end of the cord protruding from the releasable knot.
[0034] In any of the above described devices, the gas may have thermodynamic properties such that when compressed to a pressure of 10 bar, it remains in its liquid phase up to a temperature of 50°C. Alternatively, when compressed to a pressure of 16 bar, the gas remains in its liquid phase up to a temperature of 70°C.
[0035] According to yet another implementation, for a gas having thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the pressure which the flexible pressurized gas container and its outer enclosure are designed to withstand must be at least equal to the product of the intended pressure of the fully inflated flotation chamber, times the ratio of the volume of the fully inflated flotation chamber, divided by the designed volume of the pressurized gas container.Alternatively, when using a gas which has thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the flexible pressurized gas container must have a volume of at least 500 ml.
[0036] In another exemplary implementation, when using a gas which has thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the flexible pressurized gas container must have a volume of at least 250 ml.
[0037] In any of the above described devices, the compressed gas container should enable the expanding gas to expand to at least close to atmospheric pressure.
[0038] There is further provided a device for providing flotation support to an inanimate object in water, having the same components and elements as described hereinabove, but wherein the actuation release mechanism is triggered by immersion in water, or by reaching a predetermined pressure in the water.
[0039] Finally, all of the above described devices have the advantage of being valveless.
[0040] BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
[0042] Fig.l shows schematically a cross-sectional view of a valveless flotation device constructed according to the novel features of the present disclosure;
[0043] Fig. 2 shows a schematic view of a first exemplary implementation of the valveless flotation device of Fig. 1, from the direction of the closed slot of the enclosure;
[0044] Fig. 3 shows a schematic drawing of a second exemplary implementation of the valveless flotation device constructed according to the novel features of the present disclosure, implemented in the form of a life-vest, using a cord to contain the pressurized gas container and to prevent it from expanding until actuated by the actuation opening element; and
[0045] Fig. 4 is a schematic view of the device of Fig. 3, after actuation and expansion.DETAILED DESCRIPTION
[0046] Reference is now made to Fig. 1, which illustrates schematically a cross-sectional view of an exemplary valveless flotation device 10 constructed according to the novel features of the present disclosure. The flotation device example is shown in a form for attaching to the upper arm of the user, such as a swimmer, by the use of arm bands 11 connected by a buckle pair 16, though it should be understood that the inventive aspects of the device can be incorporated into flotation devices adapted for attaching to other parts of the body of a person in need. The flotation mechanism of the device itself comprises just two basic parts - the pressurized gas container 12 and the enclosure 13 in which the pressurized gas container is contained. The pressurized gas container 12 is a closed container prefilled with a compressed gas charge 14. The form of the pressurized gas container is selected according to the part of the body it is intended to support. The long folded chain form shown in the drawing of Fig. 1 is only intended to be schematic to illustrate the principle, and in practice, the form could, for instance, be a folded jacket-like form for a full body life vest, or a simple folded annulus for arm supports, and the like. Flotation devices for articles that require flotation, such as liferafts, would have an accordingly different form. The pressurized gas container 12 is prevented from inflating itself since it is contained within the enclosure 13, which is constructed such that it can withstand the forces generated by the pressurized gas in the container. The enclosure 13 can be constructed of a textile fabric or a thin plastic layer, such that it is flexible and can be comfortably worn by the user, and yet has the strength to withstand the forces exerted by the pressurized gas charge in the pressurized gas container. The schematic form of the device shown in Fig. 1, is intended to be generic in nature, and shows an arm band attachment as a simple example of how the device can be worn. Fig. 1 is not intended to be limiting in the actual implementation used, and it could also be implemented in other specific forms, such as the form of a common life-vest, with the pressurized gas container 12 being contained within an outer enclosure 13 in the form of a jacket, with the opening mechanism 15 holding the pressurized gas container in the outer jacket by means of a slot or another tying method, which includes a readily released closure element.
[0047] According to the slot implementation of the device, the flexible enclosure 13 itself has a novel opening mechanism 15, to enable the pressurized gas container to break out of the constraints of the enclosure 13, and to allow the pressurized gas, currently in its liquid or gas phase, or a combination of the two, to expand to a gas and to inflate, outside of the flexible enclosure, the pressurized gas container now acting as the flotation chamber providing support to the user.The opening mechanism 15 is shown in the region of the enclosure opposite to the arm band 11, so that it is readily accessible to the user, though any other accessible location is also acceptable. The opening mechanism comprises a slot in the enclosure wall, held closed by a combination of two separate closure arrangements, the main component being a closure mechanism, which keeps the major part of the slot of the enclosure closed, and an actuating component, which keeps a minor part of the slot of the enclosure closed, until actuated by the user, as will be fully described in relation to Fig. 2 hereinbelow. An alternative implementation using a cord to constrain the pressurized gas container from expanding, the cord representing the closure mechanism, and the knot or bow tying the cord and holding it in a closed situation, representing the actuation element, is illustrated more clearly in Fig. 3 hereinbelow.
[0048] Reference is now made to Fig. 2, which illustrates schematically a view of the flexible enclosure 13 from a side opposite the arm band 11, i.e. looking down from the top of the side view of Fig. 1, showing the details of the opening mechanism 15. As previously explained, the basis of the opening mechanism is that while the enclosure must prevent the pressurized flotation chamber within it from breaking out when not actuated, the opening mechanism is adapted to allow the pressurized flotation chamber to escape the bounds of the enclosure, by means of a simple actuation procedure which can be performed manually by the user.
[0049] In one convenient implementation, the opening mechanism 15 can be formed of a zipper mechanism 17, without a slider to open and close it, and disposed along a major part of the slot 20 cut into one surface of the enclosure 13. The two sides of the slot are designated by the characters 13a and 13b in Fig. 2. The minor part of the slot, devoid of the zipper mechanism, is held closed by a closure element 18, such as a length of adhesive tape, holding the two sides of the slot 13a, 13b, closed, but capable of being easily removed or opened by means of a tab 19 attached to it, which can be raised by finger or hand motion. The zipperless minor part of the slot is calculated to be sufficiently short that the pressure of the gas charge 14 within the constrained pressurized gas container 12, is not sufficient to allow the container 12 to break out of the toothless length with its closure element in place, and to inflate therethrough. Once the closure element 18 has been removed, the zipper mechanism on the major part of the slot can no longer hold the slot closed, and it is able to open along its length. The device is actuated by pulling off the closure element 18, at least from one side of the slot 20. Once the closure element 18 has been removed, the zipper mechanism on the major part of the slot can no longer hold the slot closed, and the force of the pressurized gas can beginto push the pressurized gas container through the now open, minor part of the slot where the closure element had been located, and exert an opening force on the end of the zipper mechanism 17. This causes the slot to open, beginning at the closure element end, where the expanding pressurized gas container is pushing through the open end, and forcing the zipper open from that end. The zipper then succumbs to the force of the pressurized gas container, and opens along its length to allow the whole of the pressurized gas container 12 to break out of the now enlarged opening of the slot in the outer envelope 13, and to fully inflate as the compressed gas expands, thus fulfilling its function as the flotation chamber. Although Fig. 2 shows the minor part of the slot being located at one end of the slot, it is to be understood that it can be located anywhere along the length of the slot, such as in the middle, with the major part of the slot being located on either side of the minor part.
[0050] The zipper mechanism shown in Fig. 2 is only one exemplary closure mechanism for holding the major part of the slot closed. A zipper mechanism may be considered to be a good choice for use as the closure mechanism, since it is very resistant to opening by means of force applied perpendicular to its plane. As explained in the summary section, a zipper mechanism opens by bending its two toothed sides outward from the direction of its axis. Therefore, in the case of the use of a zipper mechanism as the closure mechanism in the exemplary embodiment shown in Fig. 2, the zipper mechanism is opened by the pressure of the expanding pressurized gas container pushing apart the two sides, 13a, 13b, of the zipper mechanism, and thus opening the zipper mechanism from one end towards the other end. If one of the other closure mechanisms mentioned in the summary section were to be used, they could be opened by means of a force applied perpendicular to their plane, such that unlike a zipper mechanism, they can open simultaneously along the whole length of the closure mechanism. However, in order to provide a minimum force for actuating the device, the opening of the slot after removal of the closure element, would take place beginning close to the location of the closure element from where the pressurized gas container would break out from the enclosure.
[0051] Reference is now made to Figs. 3 and 4, which are schematic drawings of a second exemplary implementation of the flotation device of the present disclosure, using a cord 31 to hold the pressurized gas container 30 and to prevent it from expanding, until actuated by the actuation opening element, as mentioned previously in the Summary Section of this application. The exemplary device is shown in the form of a life vest, such as is used in aviation or nautical applications, where it may be asserted that a more critical support process is required than inapplications for swimming safety. However, it is to be understood that this second type of implementation, using a flexible cord 31 or the like to constrain the pressurized gas container 30 is not intended to be limited to any particular utilization of the flotation device, but is applicable to any suitable device to be used for flotation support. Fig. 3 shows the life vest 32 as worn and before inflation, and Fig. 4 shows the life vest 40 after inflation.
[0052] In the exemplary embodiment shown, a cord 31 is used to contain the forces of the pressure of the gas in the pressurized gas container 30, but it is to be understood that any other constraining element can be used, such as a ribbon tape, or a rope, or a net mesh. As outlined in the Summary Section of this disclosure, and in common with the constraining method for the pressurized gas containers of all of the devices using the presently described concepts, the example of Figs. 3 and 4 show the main closure mechanism in the form of a cord 31 wound spirally around the major part of the pressurized gas container 30, the ends of the cord being tied together to avoid the cord from unravelling. In Fig. 3, the cord 31 is indicated as being wound around the pressurized gas container 30, by being shown as a dashed line for that part of the winding behind the pressurized gas container 30. The closure element, which should enable easy actuation of the flotation device, is provided by the particular manner in which the connected ends of the cord, can be released. In Figs. 3 and 4, this is shown in the form of an easily releasable bow 33, such as that used to tie shoe laces. Though a bow-type knot is the type of releasable knot 33 most popularly known, it is to be understood that there are other types of releasable knots that are known, especially in the field of sailing vessels, and the presently described implementation is not intended to be limited to a shoe-lace type of bow knot. Such a releasable knot 33 can resist the outwardly directed forces applied to the cord by the pressurized gas fill, and hence can constrain the cord from unwinding from around the pressurized gas container, but at the same time, it can be readily released by manual pulling on a free end 34 of the cord protruding from the releasable knot 33. In order to enable the cord to unravel easily when the releasable knot has been released, the cord should be wound around the pressurized gas container spirally with the spacing between adjacent windings being as large as is practical while still holding in the bulging pressurized gas container 30. Once the releasable knot 33 has been released, the freed ends of the cord can slip around the now inflating pressurized gas container 41, freeing the whole length thereof from its constraint. The cord may preferably have a smooth outer surface, such that it can unravel smoothly from around the pressurized gas container. Once the cord has completely unraveled, and the gas container has fully inflated, the ends of the cord 31 may hang freely from the device, but inorder to ensure that the flotation device remains in position around the neck and chest of the user, the ends of now inflated flotation chamber may have belts or straps 42 to attach the inflated device in position on the user. The life vest described may also have a protective cover (not shown in the drawings), opening easily when the device is inflated, to prevent storage damage to the device, but it should be emphasized that such a cover is not intended to be an operable part of the device, and is not essential. Cord-bound devices of the present application, for use in other positions on the user’s body, can be implemented using the same type of structural properties as the life vest, but with the details of the attachment to the user’s body amended in accordance with the application.
[0053] The gas charge should be of a gas which has thermodynamic properties such that it remains in its liquid phase or gaseous phase when compressed into the deflated flotation bag, to a pressure of only several bar, up to the maximum temperature to which the device is expected to be exposed to. It is only as a result of usage of such gases, that the elements that constrain the pressurized gas container from inflating, whether those of the first type of slotted enclosure implementation, or of the second type of cord-constraining implementation, can be constructed of materials and components sufficiently thin and light that enables the devices to be practically implemented. The use of the prior art, high pressure gases, would require closure mechanisms and closure elements of such high strength as to make the inflatable devices too bulky to be practically functional, and to require too much force to actuate easily. The use of such gases has been described in detail in the above mentioned International Patent Application WO 2020 / 208636, and a number of examples are given there. Such gases typically remain in a liquid phase up to a temperature of 50°C when compressed to a pressure of only 10 bar or even less, or up to a temperature of 70°C when compressed to a pressure of only 14 bar.
[0054] Any of the above described flotation devices may be used for providing flotation to an inanimate object, in which case, the device may include a sensor for actuating the release mechanism automatically, (not shown in the drawings) when the sensor becomes immersed in water, or is exposed to a predetermined water pressure.
[0055] Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may beembodied in many different forms and that neither should be construed to limit the scope of the disclosure. Furthermore, it is appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of various features described hereinabove as well as variations and modifications thereto which would occur to a person of skill in the art upon reading the above description and which are not in the prior art.
Claims
CLAIMS1. A device for providing flotation support to a person in water, comprising:a sealed inflatable flexible pressurized gas container, containing a charge of a gas that, when allowed to expand, is sufficient to provide flotation support to the person in water; andan outer constraining part, encircling the pressurized gas container, and having restraining strength sufficient to hinder the outward force of the pressurized gas charge from inflating the compressed gas container,wherein the outer constraining part has an actuation release mechanism, such that when actuated, the resistance of the outer constraining part is reduced to an extent such that the outward force of the pressurized gas charge overcomes the resistance of the outer constraining part, enabling the gas charge to expand and to inflate the compressed gas container, to provide flotation support to the person in the water.
2. The device according to claim 1, wherein the outer constraining part comprises an outer enclosure comprising a closure slot having a major part held closed by a closing mechanism and a minor part held closed by a separate closure element including the actuation release mechanism for releasing the closure,wherein the closing mechanism has a resistance to opening at a level which withstands the outward force of the pressurized gas charge only when the minor part of the closure slot is held closed.
3. The device according to claim 2, wherein when the actuation release mechanism frees the closure element, the outward force of the pressurized gas within the pressurized gas container is sufficient to open a major part of the closure slot, and to enable the pressurized gas container to inflate outside of the outer enclosure.
4. The device according to either of claims 2 and 3, wherein the major part and the minor part of the closure slot have different mechanisms, the major part having a resistance to opening per unit length, higher than the resistance to opening per unit length of the minor part.
5. The device according to any of claims, 2 to 4, wherein the ratio between the lengths of the major and the minor parts of the closure slot is determined by the force exerted by thepressure of the gas charge in the pressurized gas container at its maximum rated temperature, and the resistance to opening per unit length of the minor part of the closure slot.
6. The device according to any of claims 2 to 5, wherein the resistance to opening of the minor part of the closure slot is sufficiently small that the actuation element can be operable by a hand or finger movement.
7. The device according to any of claims 2 to 5, wherein the actuation element can be operable automatically when the device is exposed to water having a predetermined depth.
8. The device according to any of claims 2 to 7, wherein so long as the major part of the closure slot remains closed and the actuation mechanism is not released, the gas container is prevented from exiting the flexible outer enclosure.
9. The device according to any of claims 2 to 7, wherein at least the major part of the closing slot comprises any one of a zipper mechanism, a Velcro section, a Ziploc section, a press stud section, or an adhesive bond.
10. The device according to the zipper option of claim 9 wherein the release of the minor part of the closing slot enables the zipper mechanism to open along its length, starting from the end of the zipper mechanism adjacent to the minor part of the closing slot.
11. The device according to any of claims 2 to 10, wherein the minor part of the closing slot comprises any of a hook and eye connection between the two opposite sides of the slot, an adhesive band connecting the two sides of the slot, or an adhesive bond connecting the two sides of the slot.
12. The device according to any of claims 2 to 11 wherein the actuation element is attached to the minor part of the closure slot.
13. The device according to claim 1, wherein:the outer constraining part encircling the pressurized gas container comprises a cord or a net, and whereinthe manually actuated release mechanism is a releasable knot in the cord or net, the release of the knot or bow enabling the pressurized gas container to expand such that the gas charge inflates the pressurized gas container.
14. The device according to claim 13, wherein the releasable knot is released by manual pulling on a free end of the cord protruding from the releasable knot.
15. The device according to any of the previous claims, wherein the gas has thermodynamic properties such that when compressed to a pressure of 10 bar, it remains in its liquid phase up to a temperature of 50°C.
16. The device according to any of the previous claims, wherein the gas has thermodynamic properties such that when compressed to a pressure of 16 bar, it remains in its liquid phase up to a temperature of 70°C.
17. The device according to any of claims 1 to 14, wherein for a gas having thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the pressure which the flexible pressurized gas container and its outer enclosure are designed to withstand must be at least equal to the product of the intended pressure of the fully inflated flotation chamber, times the ratio of the volume of the fully inflated flotation chamber divided by the designed volume of the pressurized gas container.
18. The device according to any of claims 1 to 14, wherein when using a gas which has thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the flexible pressurized gas container must have a volume of at least 500 ml.
19. The device according to any of claims 1 to 14, wherein when using a gas which has thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the flexible pressurized gas container must have a volume of at least 250 ml.
20. The device according to any of the previous claims, wherein the compressed gas container enables the expanding gas to expand to at least close to atmospheric pressure.
21. The device according to any of the previous claims, wherein the device is valveless.
22. A device for providing flotation support to an object in water, comprising:a sealed inflatable flexible pressurized gas container, containing a charge of a gas that, when allowed to expand, is sufficient to provide flotation support to the object in water; andan outer constraining part, encircling the pressurized gas container, and having restraining strength sufficient to hinder the outward force of the pressurized gas charge from inflating the compressed gas container,wherein the outer constraining part has an actuation release mechanism, such that when actuated, the resistance of the outer constraining part is reduced to an extent such that the outward force of the pressurized gas charge overcomes the resistance of the outer constraining part, enabling the gas charge to expand and to inflate the compressed gas container, to provide flotation support to the object in the water.
23. The device according to claim 22, wherein the actuation release mechanism is triggered by immersion in water, or by reaching a predetermined pressure in the water.
24. The device according to either of claims 22 and 23, wherein the gas has thermodynamic properties such that when compressed to a pressure of 10 bar, it remains in its liquid phase up to a temperature of 50°C.
25. The device according to either of claims 22 and 23, wherein the gas has thermodynamic properties such that when compressed to a pressure of 16 bar, it remains in its liquid phase up to a temperature of 70°C.
26. The device according to either of claims 22 and 23, wherein for a gas having thermodynamic properties such that it is in a gaseous phase at an environmental temperature of 0°C, the pressure which the flexible pressurized gas container and its outer enclosure are designed to withstand must be at least equal to the product of the intended pressure of the fully inflated flotation chamber, times the ratio of the volume of the fully inflated flotation chamber divided by the designed volume of the pressurized gas container.
27. The device according to any of claims 22 to 26, wherein the compressed gas container enables the expanding gas to expand to at least close to atmospheric pressure.