The present invention relates to a device for force controlling suspension of an object in a balloon.

The invention is used to mount various objects inside balloons, especially in cases when one requires a speedy mounting and at the same time would like to reduce the damaging effect of unwanted forces that may occur when an object is mounted.

For example, the invention relates to a device for use in suspending corner reflectors, information/advertisingmaterial or similar inside a balloon which is inflated and expands and/or is deformed by, for instance, visco-elastic reactions or thermal/mechanical stress.

The subject of the invention is used in particular in cases when low weight and great accuracy over a given period of time are required.

It is generally known that by placing objects inside balloons, the object will be protected from wind stress and similar and that freely flying balloons encounter less drag than they would have done had the object been suspended outside. From the time that radar came into use to track balloons with reflectors, a number of attempts have been made to keep reflectors extended inside a balloon. Here reference shall be made to, for example, US 2,888,675, US 3,276,017, US 2,463,517, EP 0182274, GB 2.152.758-A and NO 165.368.

One of the main objectives has been to reduce the consumption of gas as a result of reduced drag. The attempts have to a large degree been unsuccessful since satisfactory stability has not been obtained. Either problems arose with regard to obtaining adequate extension at the beginning or the strain became so great towards the end of the period of use that the

reflector became deformed.

A deformed reflector could inter alia reflect radar beams to one side of the transmitter/receiver, and thus give rise to a dramatic error in the reflecting signal from great altitudes/distances where the need for good reflection is greatest. In some cases, the reflector is not at all as functional as desired because the statistic variations in the expansion pattern of the balloon are too great from the very beginning.

NO 165.368 is the document that describes the most advanced art. The document describes a reflector with a cord frame of relatively low elasticity which, in essence, forms the outer limit of the reflector inasmuch as the frame is suspended by corners which buckle in when the balloon expands. These measures are, however, not sufficient to enable the balloon in an evenly expanded state to reach the desired altitudes with adequate reflective power intact.

when the balloon is to serve as an advertising balloon, the advertising material that is made in the form of inflated figures must be given a substantial embodiment, since the shape of the figures as a rule resists the spherical form that a balloon will strive towards, and for this reason they can be costly.

What is especially achieved is : the ability to suspend objects inside a balloon in such a way that the object maintains its form and function under varying conditions. For example, a balloon with a reflector would be able to function up to sufficiently great altitudes to serve a reasonable meteorological purpose, at an acceptable speed and with a moderate gas consumption.

In the case of tethered balloons, it is possible to fix objects on to a stable and protected base. At the same time, external forces can be transmitted which, for example, can

provide mobile scenes.

The invention makes use of devices that can be exemplified by a balloon with an internal reflector in the form of one or more corner reflectors, for example, arranged in an octahedral or semi-octahedral pattern, which is extended inside a balloon in that the balloon is filled and draws the reflecting plane of the reflector into orthogonal positions suitable for linear, parallel reflection of incident radar beams. The device according to the invention makes use of different measures which, to a greater or lesser extent, disengage the reflector/object from the variations of the balloon sheet material in expansion and this disengagement affects what is achieved by using resilient suspension. The actual flexibility of a higher order gained by coupling operates then, with regard to direction and/or force, in such a way that sufficient expansion is obtained as quickly as possible (i.e., with a minimum of gas consumption) and that the expansion forces are maintained at a level that does not spoil the reflection while the balloon expands or changes form in another way.

In accordance with this, the present invention relates to a device for suspending objects inside a balloon by means of fastenings on the wall of the balloon, wherein the fastenings are positioned at one or more points of suspension on the balloon wall, and are in the form of hollow protrusions of the same or different design, the wall of the balloon being adjacent to the one open end of said hollow protrusion and the second closed end thereof being fixed to the internal suspension.

In one embodiment of the device according to the invention, one or more attachment/contact points are made in the form of a cylinder/truncated cone which without the attachment of the reflector would have stood freely away from the balloon whilst it was being filled, and wherein the coupling between the

balloon and the internal object takes place at either end of said cylinder/truncated cone. During expansion, the "cylinder" is inverted as the rest of the balloon expands into the approximate shape of a sphere. The forces will then be roughly given by the cross-section of the cylinder and the positive pressure inside the balloon. Lateral forces resulting from unsymmetrical expansion will be reduced. When the cylinder has been completely inverted, there still remains an extra flexibility in the extension of the resilient material that the cylinder represents.

In accordance with a second embodiment of the device according to the invention, an embodiment which may well be used in combination with the aforementioned embodiment, a plurality of frames is provided, for example, consisting of cords which are extended to an independent, relatively rigid structure of forces from the suspension in the balloon, and where from this frame there is the possibility, especially at/by the points of suspension, of suspending additional frame (s) or reflector(s) . The stress in excess of what is necessary to mount a frame of this kind will be absorbed as inner tension in the frame. At the points where this inner tension deforms the frame, one can proceed with more or less resilient suspension of a plurality of frames from the first frame. The object that is suspended in the frame is then disengaged to a sufficient extent from variations in the balloon's expansion and deformation.

When so desired, it is possible when coupling to bypass the stabilising suspension and couple instead more directly to the balloon or, for example, via a narrow cylinder, to external forces. Additional coupling can take place by using tubing lead-ins or similar.

The invention shall be described in more detail with reference to the accompanying figures where: Figure 1 shows a balloon with an internal reflector, suspended

from a trammel which in turn is suspended from hollow protrusions;

Figure 2 is an outline of the graduation of force as a function of balloon volume/expansion for suspension from a corner and from a hollow protrusion;

Figure 3 is an outline of the correction of the direction of drag with a trammel suspension;

Figure 4 illustrates a balloon with a single reflector corner;

Figure 5 shows a balloon with a mobile scene on a mounted frame which is suspended from the balloon's hollow protrusions.

With reference to the figures, Figure 1 shows a section through a balloon (1) with an internal reflector (2) suspended from a trammel (3) which in turn is extended by forces from hollow protrusions (4) on the balloon (1) . The balloon has a convexity by (5) which results in that the internally suspended object has an uneven drag (6 and 8) relative to the orthogonality (10) which is a characteristic of corner reflectors. One can see that, due to the trammel (3), this unevenness does not spread further (7 and 9) to the actual reflector (2) . The trammel (3) and thus the reflector (2) itself remain therefore in the same position and state even though the balloon (1') ^' expands further until the protrusions (4') are completely inverted. Even on further expansion, the resilience of the protrusions will provide better protection of the reflector (2) than if one had used direct suspension on to the balloon.

in figure 2 there is an outline of the variation in suspension forces as a function of filled or expanded volume for suspension from a corner and from a protrusion. When using a protrusion, an acceptable force is obtained with less volume, and this force is maintained at an almost constant level over a larger volume area, and indeed at an acceptable level up to a larger total volume. In the case of a balloon which ascends and expands, this means that one can attain

greater altitudes before the reflector is pulled to pieces by the expansion forces.

Figure 3 shows how an uneven drag (11) from the balloon with an angle of error A effective on the trammel (3) is corrected to a less uneven drag with angle of error a effective on the reflector (2) .

Figure 4 shows a balloon with one reflector corner. A reflector with a single corner is extremely simple to produce. At the same time the one reflector corner can be made larger than the separate corners in a reflector with several corners which is placed inside the same balloon volume. Especially in instances where one wishes to monitor average wind velocity or for other reasons one is not interested in the detailed position at any given time, one can obtain a balloon that is readily made, where one saves gas and obtains a greater maximum range.

Figure 5 is an exemplification of the fact that one can obtain other functions by combining different proportions and combinations of designs within the scope of the invention. A trammel (3) is suspended (with sufficient cross members - not shown) inside the balloon (1) . A cock (15) , with a head/neck (17) which can move around the pivot (21) , is suspended from the trammel (3) by means of, for example, cords (16) . The movement of the cock's head is controlled by a cord/rod (18) which is fed through the balloon (1) in a narrow protrusion (14) . When the cord/rod is fed in and out (19) without any obstruction, the cock makes a nodding movement (20) . The actual scene that the cock exemplifies can thus have different connections to the balloon and other external forces, such as shown via the protrusion (14) , and could thus be a typical representative of an advertising purpose.