Abstract:
Apparatus primarily for the storage of a motor vehicle comprises a base sheet (10), an inner cover sheet (11) defining in combination with the base sheet (10) a storage chamber and an outer cover sheet (12) substantially wholly overlying the inner cover sheet. The inner and outer cover sheets are joined together around their peripheral edges and are at least partially releasable from the base sheet, so as to give access to the interior of the storage chamber. At least one fan assembly (19) is provided to drive air from the external ambient into the storage chamber so as to inflate it and air is allowed slowly to leak out of that chamber, either directly or indirectly through the space between the inner and outer cover sheets (11) and (12), to the external ambient. The space between the inner and outer cover sheets may be inflated by air bleeding from the storage chamber into that space, or that space may separately be inflated.

Description:
BACKGROUND TO THE INVENTION 
     a) Field of the Invention 
     This invention relates to containing apparatus for the storage of one or more products. In particular, this invention concerns such apparatus which is inflatable to define a storage chamber within which the products may be stored. Though such products may take a variety of different forms, the invention is particularly--but not exclusively--concerned with the storage of motor vehicles such as vintage cars, classic motor cycles and so on. 
     b) Description of the Prior Art 
     In my prior U.S. Pat. No. 5,566,512 I have described and claimed an inflatable storage chamber also intended for use with motor vehicles but which can be used for the storage of other products as well. That storage chamber comprises a base sheet, a cover sheet releasably connected to the base sheet, and a fan arrangement which blows air into the chamber in order to inflate that chamber, once a vehicle has been positioned on the base sheet and the cover sheet connected therearound. By controlling the flow of air through the chamber, it is found that the vehicle is stored in an excellent environment, protected against the harmful effects of moisture, dust, dirt and so on. 
     The storage chamber of my prior U.S. Pat. No. 5,566,512 is really only suitable for use within some other building, such as a garage. If the chamber is used out-of-doors, there are likely to be significant problems resulting from condensation within the chamber. Drops are likely to form on the inner surface of the cover sheet which then fall on the stored vehicle and this can give rise to damaged paint-work. Also, the plastics materials such as polyethylene from which the storage chamber of my prior patent are made are degraded by the UV rays in sunlight and the cover sheet thus has a relatively short life. 
     SUMMARY OF THE INVENTION 
     It is a principal object of the present invention to reduce the problems associated with the use out-of-doors of the storage chamber of my prior U.S. Pat. No. 5,566,512. 
     According to the present invention, there is provided containing apparatus for the storage of one or more products comprising: 
     a base sheet; 
     an inner cover sheet defining in combination with the base sheet a storage chamber; 
     an outer cover sheet substantially wholly overlying the inner cover sheet; 
     releasable fastener means permitting the inner and outer cover sheets to be at least partially disconnected from and re-attached to the base sheet so as to give access to the interior of the storage chamber; 
     fan means arranged to drive air from the external ambient into the storage chamber so as thereby to inflate the storage chamber; 
     means to control leakage of air from the storage chamber directly or indirectly to the external ambient; and 
     means to supply air to the space between the inner and outer cover sheets so as thereby to inflate said space. 
     The storage chamber is defined by a base sheet together with a cover sheet itself comprising inner and outer cover sheets which substantially wholly overlie each other, but with a space therebetween so as to permit air under pressure to be supplied thereto and thus to inflate that space and separate the sheets. By providing a storage chamber with a double skinned cover sheet, and arranging for there to be air flow through at least the chamber but possibly also through the space between the inner and outer cover sheets, problems associated with condensation can be essentially wholly eliminated. This allows the storage chamber to be used out-of-doors, without any significant probability of condensation droplets forming on the cover sheet, falling on a stored motor vehicle and damaging the paint-work. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the invention may better be understood, it will now be described in greater detail, with reference to preferred arrangements thereof. Moreover two specific embodiments of storage apparatus of this invention will also be described by way of example, reference being made to the accompanying drawings: 
     FIG. 1 is a general perspective view of the apparatus, with parts partially cut away for clarity; 
     FIG. 2 is a vertical section transversely through the apparatus of FIG. 1 but with the fan units shown in end elevation; 
     FIG. 3 is a detailed view on the join between the cover sheet and the base sheet; 
     FIG. 4 is a vertical section through one embodiment of fan unit; 
     FIG. 5 is a vertical section through an alternative embodiment of fan unit; 
     FIG. 6 is a view similar to that of FIG. 4 but of a modified form of fan unit; and 
     FIG. 7 is a view similar to that of FIG. 1, but of a further embodiment of this invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In a preferred form of the apparatus of this invention, the air supply means to said space between the inner and outer cover sheets comprises means allowing air to bleed from within the storage chamber into the space between the inner and outer cover sheets, so as to inflate that space and separate the cover sheets. In this case, the air leakage control means may be arranged to control the leakage of air from the space between the inner and outer cover sheets. Separate air leakage control means may also be provided, to control the leakage of air directly from the storage chamber itself. 
     In an alternative arrangement, the fan means may be arranged to drive air from the external ambient into the space between the inner and outer cover sheets so as thereby to separate the cover sheets and inflate the space therebetween. In this case, air bleeds means may be provided to permit air in the space between the inner and outer cover sheets to bleed into and thus inflate the storage chamber defined by the base sheet and the inner cover sheet, the air leakage control means then controlling the leakage of air directly from the storage chamber to the external ambient. 
     In any embodiment of the invention, the air leakage control means may comprise one or more special vents provided for the purpose of allowing air flow. In such a case, the vents may be made adjustable in order that the air flow rate may be controlled to some suitable value to minimise power consumption by the fan means and yet to be high enough to prevent the formation of condensation. Alternatively, or possibly in addition, the inner cover sheet may be air-permeable, at least over a part of its area, whereby the air flow between the storage chamber and the space between the inner and outer cover sheets may take place by permeation of the air through the inner cover sheet. 
     As with the cover sheet of the storage chamber described in my U.S. Pat. No. 5,566,512, the inner and outer cover sheets may be releasably attached to the base sheet around the whole of the periphery of the base sheet. Alternatively, the inner and outer cover sheets could be permanently attached to the base sheet around one, two or even three sides of the base sheet, so long as when the releasable edges are freed from the base sheet, there is still adequate access to the interior of the chamber for the article to be stored within the chamber. In the case of apparatus intended for the storage of a motor vehicle, it is convenient for both the inner and outer cover sheets to be together wholly removable from the base sheet to permit the vehicle to be driven on to the base sheet, whereafter the cover sheet may be thrown over the vehicle and the peripheral edges of the rover sheet then secured to the edges of the base sheet, all the way around the base sheet. 
     Various forms of releasable fasteners means may be employed for securing the cover sheet to the base sheet. Conveniently, a clasp fastener (such as that conventionally sold under the name Zip fastener) may be used. Other forms of similar fastener, but not using interengageable clasps, may be employed. One such fastener has a continuous pair of ribs running in a parallel manner along the edge of one component and on the other component there is a similar corresponding pair of ribs, a fastener element being slidably engaged with the ribs to urge one pair into engagement with the other pair or to release one pair from the other, dependent upon the direction of movement of the fastener element. Other possibilities would include hook-and-loop type two-part fasteners (such as those sold under the Trade Mark Velcro), lacing systems and so on. Adjustment of the fasteners will allow a degree of control of the air leakage from the storage chamber and so in turn the air flow through that chamber. 
     In order better to isolate the interior of the chamber from the external ground, it is preferred for the base sheet to have two layers with thermal insulation between the layers. 
     At least the outer cover sheet is preferably made from a plastics material which has been UV stabilised. For example, the outer sheet may be made from a polyamide sheet, suitably treated for UV stabilisation. Such a sheet may be aluminium coated and impregnated with a silicone, so as to give the material advantageous properties, including protection from up to 99% of solar UV radiation and protection against the build-up of heat due to infra-red light, as well as air, water and moisture impermeability. 
     Though it would be possible to operate the fan means continuously and to control the air flow solely by means of adjustable vents and controlled leakage, for certain conditions it may be advantageous for the fans means to be operated with a duty cycle of less than 100% the operation of the fan could be controlled simply on a time basis, though the fan means may be operated under the control of a sensor so as to perform a cyclic action, thus inflating the chamber to a maximum value and then allowing partial collapsing of the chamber before re-inflating the chamber back to the maximum value. The sensor may be arranged to monitor the pressure within the chamber, or perhaps in the space between the inner and outer cover sheets, and to control the operation to the fan means dependent upon the sensed pressure. Other possibilities include having a humidity sensor or a temperature sensor and to control the fan means dependent upon the sensed humidity or temperature, respectively. 
     In a preferred form of the invention the fan means comprises a pair of electric motor driven fans, mounted spaced apart at one end of the storage chamber, on the cover sheet, so as to draw air from the external ambient and drive that air directly into the storage chamber. Preferably, each fan is a relatively small unit driven by a low-powered 12 v dc electric motor. Each fan may be mounted in a carrier which is secured to the cover sheet, the carrier including a filter panel and also a one-way valve to prevent air leaking out of the storage chamber when the fan is not operating. Such a valve conveniently comprises a flap valve located over the exit duct of the fan and which may move under gravity or under a spring to a closed position when the fan is not operating. The carrier may also include a drain hole to allow any moisture collecting within the carrier to drain externally of the storage chamber. 
     In a modified form of fan unit, there is provided a secondary electric motor driven fan mounted on the carrier of the main motor-driven fan. A control arrangement may be provided for the secondary fan selectively to cause operation of that fan dependent upon the conditions prevailing within the chamber and possibly also externally of the apparatus. For example, to increase the air flow through the chamber, the secondary fan may be operated so as also to drive air into the chamber, in parallel with the main fan. Should the external humidity be higher than the humidity within the chamber, then the secondary fan may be turned off so that air flows out of the chamber through the secondary fan, for recirculation into the chamber by the main fan. To assist this, the main and secondary fans may draw air from a common plenum chamber. A filter may be provided over the external inlet to that plenum chamber. 
     The power supply for the or each electric motor driven fan may comprise the battery of a vehicle stored within the chamber and in this case a suitable control unit should be provided to prevent the battery voltage falling below some minimum value. The battery may be recharged for example by one or more solar panels, a wind generator or a mains operated charger. Another possibility includes operating the fan motors from the mains supply via a suitable transformer. 
     The first embodiment of storage chamber will now be described with reference to FIGS. 1 to 6. Referring to those drawings, there is shown an inflatable storage chamber comprising a generally rectangular base sheet 10, an inner cover sheet 11 and an outer cover sheet 12, the inner and outer cover sheets being of substantially the same shape and size with the outer cover sheet overlying the inner cover sheet. The inner cover sheet is releasably secured to the base sheet around its four edges, by means of a two part clasp fastener 13 (such as that kind of fastener sold under the name Zip fastener) extending wholly around the base sheet. Rather than having one long continuous fastener, it may be more convenient for some applications to have four or even more separate fasteners extending along the sides of the base sheet. The outer cover sheet 12 is secured at 14 to the inner cover sheet around the entire periphery of the inner cover sheet, just above the fastener 13. That securing should be effected in a substantially air tight manner though drainage tubes 15 may be provided at intervals along the length of the join, which tubes also allow air to leak out of the space between the two cover sheets. 
     The base sheet 10 may be relatively stiff or even semi-rigid and though not shown in the drawings, may be made from upper and lower impermeable sheets together with a layer of thermal insulating material between those sheets. The inner cover sheet 11 may be of an air-permeable material such as a microporous plastic sheet. The outer cover sheet should be air and water impermeable and typically is a polyamide sheet carrying on its inner surface a coating of aluminium and on its outer surface a silicon coating. The silicone coating renders the sheet wholly waterproof and allows easy cleaning, whereas the aluminium coating makes the sheet substantially opaque and shields any object located within the inner cover sheet from harmful solar UV radiation. In addition, the coating will reflect infra-red light and so assist in preventing a build-up in temperature within the chamber, during hours of daylight. 
     Though not shown in FIGS. 1 to 3, an additional fastener may be provided between the free edge 17 of the outer sheet 12 and the base sheet 10, so as to permit joining of the outer sheet to the base sheet. 
     Mounted in end wall 18 of the inner and outer cover sheets 11 and 12 is a pair of electric motor driven fan units 19, each of the same construction. One such fan unit is shown in FIG. 4. This has an electric motor 20 mounted on a carrier 21 attached around an opening through the inner and outer cover sheets 11 and 12. The carrier has a louvered cap 22, a foam air filter 23 being mounted between the motor 20 and the cap 22. The motor 20 drives a fan impeller (not shown) to draw-air through the unit in the direction of the arrows, a flap valve 24 being mounted on the exit duct which flap valve opens during operation of the motor but which closes when the motor is not operated, to prevent back-leakage of air. A finger guard 25 may be mounted over the inlet side of the duct within which the fan impeller rotates. 
     FIG. 5 shows a similar fan unit, but having a significantly larger air filter, as well as better shielding from atmospheric precipitation. In this arrangement, like parts are given like numbers and will not be described again here. Water drain holes 26 are provided in the bottom of the cover sheet 12. Similar holes may of course be provided in the arrangement of FIG. 4, if required. 
     The motors of the two fan units are connected in parallel to a power supply unit, for the delivery of a 12 v dc supply to the fan motors when the fans are to inflate the chamber. The power supply unit may comprise a transformer for the 240 v domestic mains supply or may be arranged to supply power from the battery of a vehicle stored within the apparatus. The power supply unit may include a sensor for monitoring one or more of the air pressure, humidity and temperature within the chamber and to control the operation of the fans dependent thereon. 
     In use, the two cover sheets are removed from the base sheet and a motor vehicle is driven on to the base sheet. The cover sheets are thrown over the vehicle and then the inner cover sheet 11 is secured to the base sheet, using the fastener 13. If a further fastener is provided around the outer cover sheet 12, then that fastener is also secured to the base sheet 10. The fan units are then operated to draw air from the external ambient so as to inflate the volume between the base sheet and the inner cover sheet 11, so that the inner cover sheet is wholly free of the vehicle stored within the chamber defined by the base sheet and inner cover sheet. The air blown into the chamber permeates through the inner cover sheet into the space 27 between the inner and outer cover sheets so as also to inflate that space as shown in FIG. 2. From there, the air leaks out of the drain tubes 15, back to the external ambient. The double-sealed construction, if used around the free edge of the outer cover sheet 12, serves to restrict leakage of air out of the chamber and also to give better control of the air flow. 
     Air holes 28 may be provided in the inner cover sheet, so as to increase the air flow from the chamber to the space 27, to ensure complete inflation of that space and also increase air flow through the chamber. The air holes may be made adjustable (for example for providing flaps secured by hook and loop fasteners) or an adjustable vent may be mounted over each air hole. If a greater air flow is required through the chamber, for example to dry a vehicle put into the chamber when wet, the Zip fastener 13 may be released for a short distance, so allowing increased leakage directly from the chamber. Alternatively, adjustable vents (not shown) may be provided from the chamber direct to the external ambient and in this case such vents should be provided in the wall of the cover sheet opposed to the wall carrying the fan units. 
     FIG. 6 shows a modified form of the fan unit shown in FIG. 4. Here, a secondary electric motor-driven fan 30 is mounted on the carrier 21, to draw air (when operated) from the space between the carrier 21 and filter 23. The operation of the secondary fan may be under the control of internal and external humidity sensors. In the event that the humidity within the chamber is greater than the external humidity (for example if a wet vehicle has been placed within the chamber) then both main and secondary fans may be operated together, to increase the air flow through the chamber and so to assist drying of the air in the chamber. On the other hand, if the humidity externally is greater than that within the chamber, the secondary fan 30 may be turned off so that air will flow in the reverse direction through the secondary fan, back into the space between carrier 21 and filter 23. From there, the air will be recirculated into the chamber, so minimising the amount of relatively wet air drawn from the exterior, into the chamber. 
     FIG. 7 shows a second embodiment of storage chamber generally similar to that of FIG. 1 and like parts are given like reference characters; these parts will not be described in detail again here. The storage chamber of FIG. 7 differs from that of FIG. 1 in that there is a plurality of spaced, substantially parallel seams 32 joining together the inner cover sheet 11 and the outer cover sheet 12, so forming a multiplicity of elongate tubular pockets 33 extending up one side of the cover sheet, over the top and down the other side. Further more, similar seams are provided on the end panels of the inner and outer cover sheets, so forming further elongate tubular pockets 34 on those end panels. In the illustrated embodiment, a passageway 35 extends around the cover sheets adjacent there lower edges, interconnecting all of the tubular pockets 33 and 34, which passageway is provided with an inlet valve to permit the inflation of all of the pockets, simultaneously. In this embodiment, no communication is provided between the space between the inner and outer cover sheets and the principal volume of the storage chamber, between the inner cover sheet and the base sheet. Thus, the pockets may be inflated separately from the inflation of the main chamber and, when the pockets are inflated, the structure will be self-supporting even without the inflation of the main chamber. 
     In the embodiment of FIG. 7, means are provided to allow the leakage of air from the main chamber, such as one or more adjustable vents (not shown) provided at the opposite end of the chamber from the fan units 19, to permit a through-flow of air through that main chamber, during operation of those fan units. In other respects, the embodiment of FIG. 7 is similar to that of FIG. 1.