GB2280296A - Improvements in and relating to folding signs. - Google Patents

Abstract

An upstanding sign, such as that commonly used as a road sign, which is constructed to fold flat when not in use has a folding mechanism which includes a hinge mechanism made up of two pairs of hinge bars 30 - 33 allowing an inner frame 14 carrying a sign plate 12 to be folded to be co-planar with and inside an outer frame 20. The outer frame is used as a base when the sign is in unfolded condition, the hinge mechanism enabling the inner frame to be repositioned in upstanding relation to the outer frame, and approximately centrally located therein. Suitably, a first bar of each pair of hinge bars is adapted to rotate through an obtuse angle when moving the inner frame from a folded position to an unfolded position, and a second bar of each pair rotates through an acute angle to the unfolded position (Figures 5(a) to 5(c)). The sign includes a blocking mechanism preventing any pant of the inner frame from passing entirely through the plane defined by the outer frame. The inner and outer frames may be constructed of identical cross-section tubing which provides a sign plate retention mechanism when use in a first orientation, and a blocking member retention mechanism when used in a second orientation through the interaction of recess 54, blocking member 70 and rebate 52 (Figure 7). The sign is readily assembled to a convenient size from standard components. <IMAGE>

Description

IMPROVEMENTS IN AND RELATING TO FOLDING SIGNS The present invention relates to upstanding display signs which are capable of being folded flat, and in particular to road signs, advertising boards and the like which require a stable, large area base when in an unfolded position.

In many applications, particularly when these are outdoors, it is desirable to use upstanding display signs which have bases adapted for stability to reduce the likelihood of the sign being blown or knocked over. One obvious approach is to incorporate substantial mass into the base of the sign, but this has drawbacks in respect of portability. Another technique used is to provide a large area base which may additionally be weighted with separate sandbags or the like.

Particularly with regard to temporary road signs which must be regularly transported from place to place, it is desirable that the sign should be capable of being folding down to a convenient size and shape during transportation and when not in use. It is also a feature of temporary road signs that they are particularly vulnerable to gusts of wind generated by passing vehicles. These gusts are substantially parallel to the direction of the road, and a sign must naturally present a large display area orthogonal thereto. It will be understood that a sign requires substantially greater stability in this direction than in a lateral direction.

The present invention is directed toward the provision of a sign which is capable of being folded flat, is easily carried, and includes a large area, highly stable base, particularly in a direction orthogonal to the display area of the sign. The present invention is also directed toward the provision of such a sign which may be easily and conveniently manufactured from a minimal number of pre-formed components.

In accordance with one embodiment thereof, the present invention provides a folding sign including a display surface bounded by an inner frame, and a base bounded by an outer frame; the inner frame adapted to lie within the same plane as, and within the boundary defined by, the outer frame when the folding sign is in the folded position; the inner frame coupled to the outer frame on each of two opposing sides thereof by a pair of hinge bars each attached to the inner frame by an inner pivot and the outer frame by an outer pivot; and the first bar of each pair being adapted to rotate about the outer pivot through an obtuse angle when moving the inner frame from a folded position to an unfolded position, and the second bar of each pair being adapted to rotate about the outer pivot through only an acute angle when moving the inner frame from a folded position to an unfolded position.

Embodiments of the present invention will now be described in detail, by way of example, and with reference to the accompanying drawings in which: Figure 1 shows a perspective view of an unfolded sign according to one embodiment of the present invention; Figure 2 shows a front view of the sign of figure 1; Figure 3 shows a side view of the sign of figure 1; Figure 4 shows a plan view of the sign of figure 1, but in folded position; Figures 5(a), 5(b) and 5(c) show a sequence of three side views of the sign of figure 1 progressing from a fully unfolded position to an almost completely folded position; Figure 6(a) shows in cross-section an exemplary type of tube extrusion useful for the construction of the sign of figure 1; figure 6(b) shows an oblique view of a "knock-in" corner joint useful for the connection of the tube extrusions; and figure 6(c) shows in diagrammatic form a corner joint and tube extrusions in exploded relation; Figure 7 shows a cross-sectional view on line A-A of figure 4; and Figure 8 shows a pivot mechanism suitable for use with the preceding figures.

With reference to figure 1 there is shown, in unfolded position, a folding sign 10 according to one embodiment of the present invention. The sign includes a display area in the form of a sign plate 12 which is held within an inner frame 14. The sign plate may be constructed from any suitable material such as plastic or metal sheet, hardboard or the like. The inner frame 14 is preferably constructed from polypropylene tube extrusions and co-operating corner joints as will be described in greater detail hereinafter. However, a metal or other frame may be utilised.

In the embodiment shown in figure 1, the inner frame 14 is, overall, rectangular in shape, and includes two short sides 15a, 15b, and two long sides 16a, 16b. Side 15b is located part way along the lengths of long sides 16a, 16b in order to bound a sign plate which has sides shorter than the lengths of the long sides 16a, 16b. It will be understood, however, that for the purposes of the present invention the sign plate may be sized such that the long and short sides 15a, 15b, 16a, 16b define a true rectangle.

The folding sign 10 also includes an outer frame 20 which, in 'the embodiment of figure 1, is also rectangular in shape, having two short sides 21a, 21b, and two long sides 22a, 22b. Sides 21 and 22 are of such dimension as to permit the inner frame 14 to lie completely within the outer frame 20 when the sign is in the folded position and the two frames are co-planar (see figure 4).

The inner frame 14 and outer frame 20 are coupled together by way of two pairs of hinge bars 30-33.

One end of the hinge bar 30 is coupled to the inner frame 14, close to an extremity of the side 16b thereof, by way of an inner pivot 36. The other end of the hinge bar 30 is coupled to the outer frame 20 by way of an outer pivot 35. The distance of the outer pivot 35 from one end of side 22b of outer frame 20 is constrained to be greater than the length of the first hinge bar 30, as will become apparent. In analogous fashion, hinge bar 31 is coupled to the inner frame 14 by an inner pivot 37, and is coupled to the outer frame 20 by an outer pivot 34.

If required for additional rigidity, an additional bar (not shown) could be provided connecting inner frame sides 16a and 16b between inner pivot 36 and inner pivot 37. The use of such an additional bar could obviate the necessity of providing side 21a of outer frame 20.

One end of the hinge bar 33 is coupled to the inner frame 14, some distance from the extremity of the side 16b thereof, by way of an inner pivot 38. The other end of the hinge bar 33 is coupled to the outer frame 20, close to an extremity of the side 22b thereof, by way of an outer pivot 40. In analogous fashion, hinge bar 32 is coupled to the inner frame 14 by an inner pivot 39, and is coupled to the outer frame 20 by an outer pivot 41.

Figures 2 and 3 illustrate the sign 10 as described above from the front and side in the unfolded position. Figure 4 shows the sign 10 of figure 1 in a folded position as viewed from above. In a preferred embodiment, the inner frame 14 has sides 16a and 16b sufficiently smaller than sides 22a and 22b of outer frame 20, such that when folded, a gap 45 is present of sufficient size to permit the passage of a hand therethrough as an aid to carrying the folded sign.

However, the sign is not precluded from having sides 16a, 16b sufficiently long to result in an exact fit inside outer frame 20.

Where a particularly tall or large sign plate is required, the sign is not precluded from having sides 16a,16b which extend beyond the ends of outer frame 20, ie. the side 15a falls outside the outer frame 20 beyond side 21a. It will be understood with reference to the description hereinafter that this particular arrangement compromises the ability of the sign to fold completely flat, but limits the base size when a particularly large sign plate is required.

If, however, side 21a has been omitted by provision of an additional bar between pivot points 36,37, the sign will be capable of folding flat.

The folding action of the sign will now be described in greater detail with reference to figures 5(a), 5(b) and 5(c).

Figure 5(a) shows the sign in unfolded position with hinge bar 32 acting as a buttress to the inner frame 14 while it is in a vertical or generally upstanding position. The lower part of the upstanding inner frame 14 is stayed against lateral movement by the hinge bar 31 and connecting inner and outer pivots 37,34 (shown in dotted outline). Preferably, in the unfolded position, the hinge bars 30 and 31 lie substantially parallel to the outer frame sides 22a and 22b. The inner frame 14 is thereby prevented from lateral movement from left to right as pictured in figure 5(a) unless such movement is accompanied by an upward movement of the inner frame 14, as is now shown with reference to figures 5(b) and 5(c). It will be understood that although the inner france is shown upstanding in a vertical orientation, the length of hinge bars 32 and 33 could be altered to provide a slightly canted sign plate 12 if this is desirable, for example, to improve visibility.

Upon lifting the inner frame 14 with respect to the base (ie. outer frame 20), it is possible to rotate the inner frame 14 as depicted by the arrows in figures 5(b) and 5(c). Hinge bar 31 (and 30, not shown) rotates through approximately 1800 about outer pivot 34, while hinge bar 32 rotates first slightly upwards, and then downwards about outer pivot 41. Figure 5(c) illustrates the folding action just prior to reaching the fully folded position.

It will be understood that the lengths of hinge bars 30-33, positions of inner and outer pivots 34-41 and lengths of sides 16a, 16b, 22a and 22b are all somewhat inter-related and may be varied in order to achieve the folding capability in combination with optimum stability and sign plate angle.

Preferably, hinge bars 30,31 rotate about the outer pivot through a full 1800 during the folding action, although a slightly smaller angle is possible.

Preferably, the hinge bars 32,33 rotate about the outer pivots 40,41 through an angle of approximately 45" or less. Preferably, the length of hinge bars 30 and 31, and positions of pivots 34 and 35 are determined to ensure that the upstanding inner frame is located toward the centre of the sides 22a and 22b of outer frame 20. This provides maximum resistance to falling over in either the left or right direction of figure 5(a).

When the sign is in the unfolded position as pictured in figure 5(a), the outer frame may be used as a base upon which to place sandbags or the like, or with which to peg the sign to the ground in order to provide further stability, although this will not normally be necessary.

In accordance with a further embodiment of the present invention, it is desirable to provide a mechanism to prevent the inner frame from folding right through the outer frame, and also to provide a convenient, readily adaptable method of manufacturing such signs of any desired dimensions.

With reference now to figure 6(a), there is shown in cross-section an extruded polypropylene tube 50 suitable for the manufacture of such signs.

Other materials may be used in the manufacture of such tube 50. This tube 50 is adapted such that the cross-section of tube provides for its use in both the construction of the inner frame 14 and the outer frame 20, incorporating the features necessary to provide a sign plate 12 retention mechanism, and also a mechanism for preventing the inner frame 14 folding right through the outer frame 20 as identified above.

In the illustrated embodiment, the extruded tube 50 is of broadly rectangular cross-section, but includes a longitudinal rebate 52 on one corner thereof. Proximal to the diagonally opposed corner to the rebate is a longitudinal recess 54. The tube 50 includes a hollow centre 55. The longitudinal recess 54 is adapted to be of sufficient depth and width to securely retain the edges of sign plate 12 (figure 1), and also to securely retain a blocking strip of equal thickness to the sign plate as will be described hereinafter. The longitudinal rebate 52 is adapted to be of sufficient depth to allow flat folding of the sign also as will be described hereinafter.

With reference to figure 6(b), there is shown an oblique view of a "knock-in" corner joint 60 which includes two male connector portions 61 adapted to cooperate with the hollow centre 55 of tube 50. A rebate 62 is provided to correspond to the longitudinal rebate 52 provided on tube 50, and also, dependent upon orientation of the tube 50, to allow space for sign plate 12 when installed in longitudinal recess 54. The corner joint 60 may 'be provided with a hole 65 therethrough to assist in assembly and disassembly of the sign.

Figure 6(c) shows an exploded diagram viewed from above of the corner joint 60 and two tubes 50. Although the tubes 50 are represented with the recess 54 (in dotted outline) facing inwardly and uppermost on the tube, it will be appreciated, particularly with reference to figure 7, that the tubes may be longitudinally inverted, and the corner joint rotated through 1800 about its diagonal axis "X" (figure 6(c)) to allow the recess 54 to face inwardly and be lowermost.

With reference to figure 7, the constructional detail of the inner and outer frames 14,20 is shown by a cross-section through the line A-A of figure 4, but with the hinge bar 33 omitted for clarity. The inner frame 14 has the tubes 50 thereof presented with the recess 54 facing inwardly and uppermost to retain the sign plate 12 close to the upper surface of the tube 50. The outer frame 20 has the tubes 50 thereof presented with the recess 54 facing inwardly and lowermost to retain a blocking member 70 close to the lower surface of the tube 50. When the sign is folded, as depicted in the figure 4 cross-section, the blocking member 70 comes into engagement with a face of rebate 52, preventing further travel of the tube 50 which forms a side 16a of the inner frame 14.

It will be understood that the relative dimensions of the recess 54 and rebate 52 are variable, but such as to enable the sign plate 12 and blocking member 70 to be gripped by the tubes, and to allow the sign to be folded completely flat with no projecting part of either the sign plate 12 or blocking member 70. In the embodiment herein described, the sign plate and blocking member are slightly recessed below the upper and lower surfaces of the tubes 50. thereby providing protection against scratch damage to the sign plate when the signs are being stacked against one another. The total thickness of the folded sign 10 is no greater than the thickness of the tubes 50 used in their construction.

It will be understood that the signs may be manufactured from any desired lengths of tube 50 using the corner joints 50 as required. The hinge bars 30-33 may be attached to the tubes to form the appropriate pivots 34-41 using a variety of techniques. For example, the pivots could be constructed as shown with reference to figure 8. A hole 75 is drilled into the tube 50 at an appropriate point (two examples shown in figure 8), and holes 76 are also drilled through the ends of the hinge bar 30,31,32 or 33. A snap-fit rivet 77 is then pressed through the hinge bar hole 76 and wall of the tube 50 via hole 75.

A number of benefits are realized with the use of knock-in corner joints 60 and longitudinal rebates 52 to retain the sign plates. In particular, the sign plates are readily interchangeable by hooking out the knock-in joints 60, eg.

using an appropriate tool inserted into hole 65. Only the two joints at the upper ends of long sides 16a, 16b need be extracted to remove short side 15a.

Sign plate 12 may then be slid out from the retaining rebates of sides 16a, 16b and 15b, and replaced with an alternative plate carrying the appropriate legend.

Replacement of short side 15a and the two corner joints 60 then retains the new sign plate in position. No clips, bolts or rivets are required to retain the sign plate, and this is advantageous in that there are no detachable small parts to be easily lost.

A further benefit of the sign plate retention mechanism as described herein is the capability to retain supplementary sign plates without modification.

For example, a common arrangement for a roadside sign is an upper graphic portion, such as the "roadwork" symbol, and a lower textual portion, such as "200 yards". For maximum flexibility, it is desirable that the two portions of the sign be carried on two different plates. Thus, two sign plates of appropriate dimensions may be inserted into the frame in this fashion, allowing modification of the textual portion without changing the graphic portion.

Alternatively, an additional short side 15b (not shown) could be used to separate the two sign plates. The additional short side could be integrated with the inner frame construction by using appropriately formed knock-in joints having three-way male connector portions 61.

Claims (12)

1. A folding sign capable of being folded substantially flat and including: a display surface; two pairs of hinge bars, a first bar of each pair being adapted to provide support for the sign to hold the display surface in an upstanding position, and a second bar of each pair being adapted to lock the display surface against movement thereof in a direction orthogonal to the display surface.

2. A folding sign including a display surface bounded by an inner frame, and a base comprising an outer frame; the inner frame adapted to lie within the same plane as, and within the boundary defined by, the outer frame when the folding sign is in the folded position; the inner frame coupled to the outer frame on each of two opposing sides thereof by a pair of hinge bars each attached to the inner frame by an inner pivot and the outer frame by an outer pivot; the first bar of each pair being adapted to rotate about the outer pivot through an obtuse angle when moving the inner frame from a folded position to an unfolded position, and the second bar of each pair being adapted to rotate about the outer pivot through only an acute angle when moving the inner frame from a folded position to an unfolded position.

3. The folding sign of claim 2 wherein the first bar is adapted to rotate through an angle of approximately 1800 such that in the unfolded position the inner frame lies in upstanding relation to the outer frame.

4. The folding sign of claim 3 including a blocking member located within the outer frame adapted to prevent any portion of the inner frame passing completely through the plane of the outer frame.

5. The folding sign of claim 4 wherein the blocking member comprises an inwardly projecting strip attached to the inner face of the outer frame by way of a longitudinal recess formed in said face; and wherein the sign plate is attached to the inner face of the inner frame by a similar recess formed in said face, the planes of said recesses being mutually offset from one another.

6. The folding sign of claim 5 wherein the offset is effected by forming the inner and outer frames of identical cross-section tubes, being longitudinally inverted with respect to one another.

7. The folding sign of claim 6 wherein the tubes include a rebate formed in the opposite face to the face in which the recess is formed.

8. A folding sign including a display surface bounded by an inner frame, and a base bounded by an outer frame; the inner frame adapted to lie within the same plane as, and within the boundary defined by, the outer frame when the folding sign is in the folded position; the inner frame and the outer frame coupled by a hinge mechanism adapted to allow the inner frame to be brought into acute angular relation to the outer frame; the inner and outer frames both constructed from tubes of identical crosssection, the tubes including a longitudinal rebate along one corner thereof, and a longitudinal recess along a diametrically opposed corner thereof; and at least one side of the inner and outer frames having their respective tubes in longitudinally inverted relation to one another such that the recess of the inner frame faces inwardly from the frame and retains a sign plate, and the recess of the outer frame also faces inwardly and retains a blocking member which is adapted to cooperate with a side of the rebate on the inner frame.

9. An extruded tube for the construction of folding signs, the tube being of cross-sectional shape substantially as depicted in figure 6(a).

10. A folding sign according to claim 1 further including an inner frame having a longitudinal rebate on inner surfaces thereof, the rebate being adapted to accommodate edges of a sign plate which forms the display surface and to retain the sign plate within the inner frame.

11. A folding sign according to claim 10 wherein the inner frame includes at least two detachable corner joints enabling removal of one side of the inner frame to facilitate sliding removal and replacement of the sign plate.

12. A folding sign according to claim 10 including a plurality of sign plates retained within the inner frame by the longitudinal rebates.