IES68341B2 - Display and advertising unit - Google Patents

Abstract

A display or advertising unit which comprises a plurality of vanes 14 which may carry advertising matter on one or both sides. The vanes 14 are supported for movement around a closed path 16 and each vane is pivoted for deflection to either side of the closed path by rotation about an axis 15 at an angle to its direction of movement along the path. Stop means limit the angle of pivotting of each vane 14 on at least one side of the closed path 16 such that, at least for a given direction of fluid flow relative to the display unit, the cumulative pressure exerted by the fluid on the vanes 14 provides a net force tending to drive the vanes around the closed path 16.

Description

DISPLAY AND ADVERTISING UNIT This invention relates to a display and advertising display unit.

According to the present invention there is provided a display and advertising unit comprising a plurality of vanes which may carry advertising matter on one or both sides, a support means on which the vanes are mounted for movement around a closed path, each vane being pivotally mounted on the support means for deflection to either side of the closed path by rotation about an axis at an angle to its direction of movement along the path, and stop means for limiting the angle of pivotting of each vane on at least one side of the closed path such that, at least for a given direction of fluid flow relative to the display unit, the cumulative pressure exerted by the fluid on the vanes provides a net force tending to drive the vanes around the closed path.

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: x Figures 1 (a) and 1 (b) are perspective and side views respectively of a first embodiment of the invention, Figure 1(c) is a cross-sectional plan view of the first embodiment, taken on line C-C of figure 1(b), Figure 2 is a perspective view of a second embodiment of the invention.

See 34 1 a Figures 3 (a) and 3 (b) are perspective and plan views respectively of a third embodiment of the invention, Figure 3(c) is an enlarged detail of figure 3(a), and Figure 4 is a schematic plan view of a fourth embodiment of the invention.

Before describing the embodiments, it should be made clear that the use of terms such as vertical”, horizontal, upper, lower, left, right and the like when describing any particular embodiment is intended to refer to that embodiment as viewed in the figures being referred to, and is not intended to limit the orientation of any particular embodiment in use.

Referring to figures 1(a) to 1(c), a display or advertising unit according to the first embodiment of the invention is in the general form of a drum or cylinder 10 comprising axially spaced circular top and bottom plates 11 mounted for rotation about a substantially vertical axis 12. A plurality of similar flat vanes 14 are mounted at intervals around the periphery 16 of the drum 10, i.e. between the circumferential edges of the plates 11, for movement . around the closed circular path defined by the periphery 16 as the drum 10 rotates. — Each vane 14 is pivotally mounted at the periphery 16 * of the drum 10 for rotation about an axis 15 substantially parallel to the axis 12, i.e. at right i angles to the direction of movement of the vanes 14.

Thus each vane can be deflected inside the periphery 16 of the drum, as seen for the vanes generally at the top and right hand side of figure 1(c), or outside the «» periphery 16 of the drum, as seen for the vanes generally at the bottom and lower left hand side of the A drum in figure 1(c) .

In use each vane 14 may carry advertising or promotional matter (not shown) on one or, both sides. Although the drum 10 is shown as relatively shallow in figures 1 (a) and 1 (b) , the height of the drum, and hence the height of the individual vanes 14, can be selected to be any desired height.

The deflection of each vane 14 is limited by stop means to an angle theta on each side of the periphery 16, as indicated for the vane 14' at the 3 o'clock position in figure 1 (c), but can pivot freely between these two extreme positions. The stop means is not shown but may be of a kind shown in the embodiment of figures 2(a) to 2(c). The angle theta may be from 0.5 to 179.5 degrees, and in figure 1(c) it is assumed to be about 60 degrees. Since the drum 10 consists essentially only of the circular top and bottom plates 11 with the vanes 14 pivotally supported between them, the drum 10 is hollow and fluid flow is possible between the vanes 14 and through the interior of the drum 10.

When a fluid such as air is flowing relative to the drum 10 in the direction indicated by the arrow 20, figure 1(c), those vanes 14 which at any given moment are generally on the right of the drum, i.e. from about * 30 the 12 o'clock position to the 4 o'clock position in figure 1(c), are deflected inside the drum periphery by 1 fluid pressure until they come to stop against their respective stop means. These vanes are referred to herein as active, which is to say that they are held non-parallel to the fluid flow direction 20 and hence offer resistance to the fluid flow. This resistance causes a pressure drop across the active vanes which tends to drive the drum 10 in the direction of rotation indicated by the arrow 22. It will be seen that each active vane 14 tends to drive the drum 10 in the same (clockwise) direction and therefore their effect is cumulative.

Those vanes 14 which at any given moment are generally on the left of the drum 10, i.e. from about the 7 o'clock position to the 11 o'clock position in figure 1(c), are free to feather in the fluid flow between their stop positions, and hence offer little resistance to the fluid. These vanes are referred to herein as passive vanes.

At about the 5 o'clock position of the drum 10, as seen within the circled region 24 in figure 1(c), each vane flips over or reverts from being inside the periphery 16 to being outside the periphery 16. However, it remains active for a short while (until about the 7 o'clock position) because the fluid pressure drives it against its opposite stop means and it remains held non-parallel to the fluid flow direction 20 until rotation of the drum 10 brings it parallel to the fluid flow direction 20 at around the 7 o'clock position.

Thereafter it becomes passive and is free to feather between its stop positions until about the 12 o'clock position. During the passive state each vane once again rotates from outside to inside the periphery 16 (at about the 9 o'clock position) ready for another * reversion at the 5 o'clock position. i The result is that the pressure cumulatively exerted by the fluid on all the vanes 14 provides a net force tending to drive the drum 10 in the direction of rotation 22, because the pressure on the active vanes * tending to drive the drum in the direction 22 is greater than the drag on the feathered passive vanes. Λ Thus, provided the fluid is flowing strongly enough that this net force is sufficient to overcome the mechanical friction of the drum 10, the drum will rotate and continue to rotate all the while the fluid is flowing. It will be observed that in this embodiment, due to the circular symmetry of the drum 10, the display or advertising unit works equally effectively whatever the direction of fluid flow.

If desired, the deflection of each vane 14 could be limited on only one side of the periphery 16. For example, if the deflection of each vane were limited only on the inside of the periphery 14, after reversion the vanes would immediately .be permitted to feather, and thus become passive earlier than they otherwise would. This is indicated by the dashed lines on the three vanes in the region of the 6 o'clock position in figure 1(c). On the other hand, the deflection of each vane could be limited only on the outside of the periphery 14. This would lead to a different configuration of active and passive vanes as the drum rotates, but there would still be a net force tending to drive the drum 10 in one direction.

The result is therefore a unique display or advertising unit which is fascinating to watch as the vanes flip over at a particular point around the closed circular path along which they travel, which is of low cost with few components and no power requirement, and which Λ requires little maintenance.

Turning now to figure 2, a second embodiment of the display or advertising unit, is essentially the same as that of figures 1(a) to 1(c) except that the top plate is omitted; accordingly, the same reference numerals have been used for the same or equivalent parts. Thus the bottom plate 11 is mounted for rotation about a substantially vertical axis 12 and a plurality of similar upstanding flat vanes 14 which may bear advertising or promotional matter 30 on one or both sides are mounted at intervals around the periphery 16of .the plate 11 for movement around the closed circular path defined by the periphery 16 as the plate 11 rotates. As before, each vane 14 is pivotally mounted at the periphery 16 for rotation about an axis 15 substantially parallel to the axis 12 so that it can be deflected inside the periphery 16 of the plate 11 or outside the periphery 16, and stop means are provided to limit the deflection of each vane on at least one side of the periphery 16. The principle of operation of the embodiment of figure 2 is the same as that of figures 1(a) to 1(c).

Referring now to figures 3(a) to 3 (c), a further embodiment of the invention comprises upper and lower chains 60', 60 which pass around upper and lower pairs 62' and 62 respectively of sprocket-type wheels. The sprocket wheels 62', 62” vertically one above the other at each end of the apparatus are mounted on respective hubs 64, figure 3(c), for rotation about parallel axes 66.

The chains 60 comprise rigid links 68 pivotted end to end at pivot points 70, each pivot point 70 in the 4 upper chain 60* being located vertically above a respective pivot point in the lower chain 60 . A < plurality of vanes 72, each of which may carry advertising matter on one or both sides, are mounted vertically between the chains 60' and 60. In particular, each vane 72 is mounted for pivotting about a vertical axis passing through a respective pair of vertically aligned pivot points 70, so that it can be deflected either to the inside or to the outside of the closed path 73 defined by the movement of the chains 60 around the sprocket wheels 62.Thus the vanes 72 along the run of the chains 60 nearest the viewer in figure 3(a) and at the bottom of figure 3(b) are deflected outside the closed path 73 whereas the vanes 72 along the top run of the chains 60 furthest from the viewer, in figure 3(a) and at the top of figure 3(b) are deflected inside the closed path. In this connection it will be seen that each vane 72 has major and minor surface area portions 72' and 72, figure 3(b), on opposite sides respectively of the axis of deflection of the vane. Accordingly, in this specification a reference to the vane being deflected to one side or the other of the closed path is to be understood to be a reference to the major surface area portion of the vane being so deflected.

Each link 68 further carries a pair of fixed stop arms 74 arranged in a V-shape and each bearing a stop member 76 at its free end. These stop members 76 limit the deflection of each vane 72 to an angle theta on each side of the closed path, as described for the embodiment of figures 1(a) to 1(c).

This embodiment operates as follows. Referring to figure 3(b), fluid flow in a direction towards one side of the display unit, for example as indicated by the arrows 78, causes the vanes 72 on that side to be deflected inside the closed path 73. However, they are there constrained by the stop members 76 and hence they are held in an active position non-parallel to the fluid flow direction. This tends to drive the chains 60 in the direction of the arrow 79.

After passing through the display unit the fluid exiting from the other side deflects the vanes on the exit side outside the closed path. In this case the vanes 72 are also held in an active position by the respective stop members 76, which also tends to drive the chains 60 in the direction of the arrow 79.

Overall, therefore, and provided the distance between one inverting vane and the next is sufficient to allow the particular fluid to flow through the apparatus without significant element of stalling, the cumulative pressure exerted by the fluid on the vanes 72 provides a net force tending to drive the chains 60 around the closed path 73. Although figure 3 (b) shows the fluid incident at 90 degrees to the longitudinal direction of the display unit, it will work for a wide range on incident angles.

Figure 4 shows a modification of the embodiment of figures 3(a) to 3 (c) which differs solely in that only one arm 74 and stop member 76 is provided on each link 68, so that the deflection of the vanes 72 is constrained only on the inside of the closed path 73. Thus the vanes 72 on the far side of the apparatus from the oncoming fluid are free to feather. This is shown for the vanes along the lower run of the chains 60 in figure 4, assuming that the fluid is flowing in the direction indicated by the arrow'80. Nevertheless, the pressure cumulatively exerted by the fluid on all the vanes 72 provides a net force tending to drive the chains 60 in the direction indicated by the arrow 82, because the pressure on the active vanes tending to drive the drum in the direction 82 is greater than the drag on the feathered passive vanes.

While it is anticipated that the above embodiments will normally be located in use in the open air so as to be driven by the wind or indoors in conditions of forced convection, it is quite possible that they could be located partly underwater or underwater where they could be viewed by observers in, for example, an underwater observatory and in such a case they would be I driven by currents in the water.

If desired a supplementary energy source such as an electric motor can be provided for the above embodiments to maintain the movement of the vanes around the closed path when fluid flow (wind or water current) is absent or of insufficient strength to operate the unit.

It is also preferable that when in a stationary position the vanes take up a specific orientation.

Claims (5)

CLAIMS:

1. A display or advertising display unit comprising a plurality of vanes which may carry advertising matter on one or both sides, a support means on which the vanes are mounted for movement around a closed path, each vane being pivotally mounted on the support means for deflection to either side of the closed path by rotation about an axis at an angle to its direction of movement along the path, and stop means for limiting the angle of pivotting of each vane on at least one side of the closed path such that, at least for a given direction of fluid flow relative to the display unit, the cumulative pressure exerted by the fluid on the vanes provides a net force tending to drive the vanes around the closed path.

2. A display or advertising unit as claimed in claim 1, wherein the stop means limits the angle of pivotting of each vane on each side of the closed path.

3. A display or advertising unit as claimed in any preceding claim, wherein the support means supports the vanes for movement along a circular path.

4. A display or advertising unit as claimed in any one of claims 1 to 3, wherein the support means is in the form of a chain or belt passing in a closed path — around at least two guide members rotatable about substantially parallel axes.

5. A display or advertising unit substantially as t described herein with reference to figures 1(a) to 1(c), to figure 2, to figures 3(a) to 3(c), or to figure 4 of the accompanying drawings.