English translation of PCT/ΝL95/00331

A DEVICE AND A METHOD FOR SUPPORTING A FLAT OBJECT. SUCH AS AN ADVERTISING BOARD

The invention relates to a device in which a substantially flat object, for example an advertising board, may be placed, said device at its upper side comprising fastening means for securing an object, whereby said object is kept in a substantially vertical position.

A device of this kind, also called a display, may be used for placing an advertising board outside, permanently or temporarily, where it may blown down by the wind. Such a device must meet a number of requirements. In the first place it must be readily movable, so that it can be placed outside during the day and be taken inside for the night. Furthermore it must be simple and inexpensive in order to minimize the risk of theft. A very important requirement is that it must be able to withstand gusts of wind.

It is known to suspend an advertising board in a movable frame, whereby the advertising board, hereinafter briefly called "board", can swing away in the direction of the wind under the influence of said wind, so that no great forces are exerted on the frame. Such a frame must be of very solid construction and be provided with a heavy base, in order to prevent it from being blown down under the influence of the wind. Furthermore the pivoted suspension device is rather complicated, so that all in all it is not of a simple construction.

It is also known to support such a board at its bottom side by means of one or more helical springs, in that case said helical springs must be mounted in a very heavy base, however, in order to obtain sufficient stability.

The object of the invention is to provide a device for supporting a substantially flat object, whereby said object can swing away under the influence of the wind and whereby said device is of simple, not too heavy construction.

In order to accomplish that objective according to the invention the device is at its upper side provided with fastening means for fastening the object, and with a convex surface at its bottom side, such that in a position of rest the device keeps the object in a substantially vertical position, whereby in another position the centre of gravity of the device with the object is located such that the device will move towards said position of rest under the influence of gravity. Because the substantially flat object, hereinafter called board, may be of relatively light construction, a self-righting effect may be achieved when the weight and the shape of the base in which the board is secured are suitably selected, as is also known with children's toys in the shape of a self-righting tumbler.

In a preferred embodiment of the invention at least part of the bottom side of the device is substantially in the shape of a part of a cylindrical surface. As a result of this the device can roll away in two opposed directions. During said rolling away the board is positioned on one side of the line of contact between the device and the ground, whilst a very large part of the mass of the device is positioned on the other side of said line of contact, so that the resulting torque being exerted on the device results in the board being raised to a substantially vertical position. By designing the bottom side of the device as a part of a cylindrical surface, a relatively large part of the mass of the device may be located in the lower central part of the device, which has a positive effect on the self-righting force of the device. It is possible to allow the board to swing away in only two opposed directions perpendicularly

to the board, because it is precisely in those directions that the wind may exert a great force on the board.

By making that part of the device which is positioned close to the ground in the position of rest, which is located in the central part, therefore, extra long in axial direction, it is possible to obtain a distribution of mass of the device which results in an even greater self-righting force.

The device may be made of concrete, but it may also consist of a container, for example made of plastic material, which may be filled with water, sand or gravel in order to obtain sufficient mass.

Because the self-righting force of the device according to the invention is relatively large, a relatively small mass will already be sufficient to give the device the required self-righting force. By constructing the device in the shape of a container, in which material may be provided, the device is easy to manufacture and transport.

In order to further increase the self-righting force of the device, said device may on opposite sides be provided with substantially upwardly extending parts, on the upper part of which the device rests when the board is pushed down to the maximum extent. In addition it is possible to design such upwardly extending parts in the shape of a handle, so that the device can be carried without difficulty. For example, two handles may be provided on either side of the device, so that the device can be readily carried by two persons, whereby the board may be mounted in the device.

The device may be provided with fastening means, in the shape of a slot at the upper side, for fastening the board. Preferably said slot extends in axial direction with respect to the aforesaid cylindrical surface. The slot may

be conical in downward direction, whereby the side walls of the slot are provided with inwardly extending protrusions for engaging the board. Such a board may for example have a thickness of 10 mm and be made of a very light material.

The board may be mounted in the device by a clamping means, for example made of plastic material, which is wedge-shaped in downward direction and which is provided with a slot in which the board may be placed. By moving the wedge shape of said clamping means into a conical part of the device, the board may be secured in the slot of said clamping means. The clamping means may thereby be provided with a stud extending through the device to the bottom side thereof, whereby said clamping means can be pulled down by threading a nut on to said stud, which nut will be located at the bottom side of the device. It is preferred to use a wing nut for this purpose, so that board can be secured by hand.

The invention furthermore relates to a method for keeping a substantially flat object, such as an advertising board, in an upright position, whereby said object is at its bottom edge secured in a relatively heavy device, which is at its bottom side provided with a convex surface, preferably in the shape of a part of a cylindrical surface. Such a method for supporting an advertising board is effective and inexpensive.

Since the substantially flat object, such as an advertising board, is only engaged at its bottom side, the rest of the object may have any desired shape, which may for example be adapted to the illustration on the advertising board.

The invention will be explained in more detail in the following description of an embodiment thereof, wherein reference is made to the drawing.

Figure 1 is a plan view of the device; Figure 2 is a side view of the device; Figure 3 is another side view of the device; Figure 4 is a sectional view along the line IV-IV; Figure 5 is a sectional view along the line V-V;

Figure 6 shows how an object is mounted in the device; and Figure 7 is a perspective view of the device fitted with an advertising board.

The figures are only schematic illustrations of the embodiment, whereby like parts are numbered alike in the various figures.

The device according to Figure 1 consists of a container 1 of plastic material, provided with a closable opening 2, through which said container can be filled with water, for example. The bottom side 3 of the container 1 has a cylindrical surface, at least partially so, which is apparent in particular from the view according to Figure 3. Said cylindrical surface enables the device to make a rolling movement on the ground, whereby the device maintains a substantially straight line of contact with the ground.

The device is furthermore provided with two upright parts, each in the shape of a handle 4. The illustration according to Figure 3 shows that the device can make a rolling movement, in such a manner that even the handle 4 will touch the ground. When the device is sufficiently heavy, because the container 1 is for example filled with water, the centre of gravity of the device will be so low that a resulting torque is present at all times during said rolling movement, which torque will move the device to the position shown in Figure 3. In particular when the rolling movement is carried through so far that one handle 4 touches the ground, the self-righting force is relatively great.

At the upper side 5 the device is provided with a slot 6, which extends in axial direction with respect to the cylindrical surface. An object, for example an advertising board, may be place in said slot 6, which advertising board is so light that the device and the advertising board together will have a self-righting power at all times.

The slot 6 is slightly conical, which is in particular apparent from the sectional view according to Figure 5. The slot is thereby provided with protrusions 7, which extend inwards and which may butt against the advertising board.

Figure 4 shows a cross-sectional view of the central part of the device, showing a part of the upper wall 8 as well as a part of the bottom wall 9 of the container in sectional view. It is thereby shown that both the upper side and the bottom side of the device are provided with an inwardly extending conical part, which parts are substantially frustoconical, and which are interconnected by a hole 10.

Figure 6 shows the fastening of an advertising board 11 in the slot 6 of the device. The board 11 is to that end inserted into a clamping means 12 of a flexible material, which is at its bottom side provided with a stud 13. When the board 11 is fitted in the slot 6 said clamping means 12 is positioned within the conical recess 14 and the stud 13 extends through the hole 10. By threading wing nut 15 on to stud 13 the clamping means is pulled down into the conical recess 14, as a result of which a clamping action is exerted on the board 11, so that the board is secured in the clamping means 12.

Figure 7 schematically shows the device provided with an advertising board 11, which is at its bottom side secured in said device. Because only the bottom side of the advertising board 11 is secured, it is possible to give the

other parts of the board any desired shape, as is shown in Figure 7 by means of an outwardly extending hand and an arrow pointing at the board. It will be apparent that, apart from the bottom edge of the board 11, the board may be given any desired circumferential shape.

The illustrated and explained embodiment only serves to illustrate the invention, which comprises a great many further embodiments.

It is also possible to connect the substantially flat object integrally with the container, so that a self- righting device is obtained, which comprises a flat part, to which a poster may be affixed, for example.

Furthermore it is possible according to the invention to support an advertising board by means of several devices according to the embodiment. In that case said devices are each secured to the bottom edge of the advertising board. Another possibility is to interconnect said devices by means of a section first, which section is secured in each of said devices and which is provided with fastening means for the advertising board.

The clamping means may furthermore be made larger, so that it extends above the device and is capable of securing a thicker advertising board. Furthermore it is possible for one device to comprise two clamping means.