GB2113087A - Folding umbrella - Google Patents

Abstract

A frame for a foldable umbrella has main stretchers 23 pivotally connected at their lower ends with a lower boss slidable along the umbrella shaft, and pivotally connected at their upper ends with ribs 24, the main stretchers 23 being pivotally connected intermediate their ends with the lower ends of respective auxiliary stretchers 21 which in turn are pivotally connected at their upper ends to an upper boss fixed to the shaft. By contrast with known arrangements, however, each auxiliary stretcher is in the form of a thin strip which, at a position just above its pivotal connection with a tension link 20, is cranked so that the upper portion of stretcher 21 is offset with respect to, but parallel with, the lower portion and the plane of pivotal movement of the main stretcher, rib 24 and link 20. The slots in the upper boss which receive the auxiliary stretchers are corresponding offset. As a result, in the folded condition, the upper ends of stretchers 21 are disposed circumferentially between the upper ends of stretchers 23, instead of the main stretchers being disposed radially outwardly of the auxiliary stretchers as is conventional, so that the radial dimensions of the folded umbrella at the tail end are reduced. The heads 22 of the ribs 24 lie entirely below the upper boss, rather than radially outwardly thereof. <IMAGE>

Description

SPECIFICATION Folding umbrella This invention relates to a foldable umbrella framework for an umbrella of the sort which, in the fully folded condition has a length substantially less than the radius of the umbrella when fully opened, so that in its fully folded condition is convenient for carrying and packing and has a neat and compact appearance.

More particularly, the invention relates to a foldable umbrella frame of the sort comprising a main stretcher pivotally connected at one end to a lower boss slidable on said central column, an auxiliary stretcher pivotally connected at one end to an upper boss fixed to said central column and pivotally connected at its other end with said main stretcher at a position intermediate the ends of said main stretcher, a rib pivotally connected intermediate its ends with the end of said main stretcher remote from said first boss, said rib having an outer free end for attachment to the periphery of an umbrella cover and having, at its opposite end, a head pivotally connected with one end of a tension link pivotally connected at its opposite end with said auxiliary stretcher at a position intermediate the ends of the latter, the pivotal connection in any said linkage having pivotal axes all substantially parallel with one another and extending in a direction perpendicular with the axis of said central column.

In a typical known umbrella incorporating a frame of this sort, in the folded condition, the tail part (i.e. the part which corresponds to the centre and top of the unfolded umbrella), appears rather bulky and this bulk detracts from the appearance of the umbrella when folded. Apart from considerations of appearance, the bulk of the umbrella in the fully folded condition, and particularly the fact that the overall diameter of the tail part of the folded umbrella is bigger than that of any other part, makes it troublesome and time-consuming to put the folded umbrella into its jacket.

Furthermore, if such an umbrella is to be put into a lady's handbag or a gentleman's suitcase or packed in any other way, it occupies a lot of space, thus reducing the space otherwise available for other articles. In terms of export (and also domestic sales) the transport cost of such umbrellas depends on the volume occupied by the packed umbrellas. If each umbrella has a larger volume than necessary, the number of umbrellas a carton can load will become less than might be and therefore the number of cartons needed to accommodate the same total number of umbrellas in one shipment will be increased, thus raising transport costs.

It is an object of the invention to provide an improved foldable umbrella framework which, when incorporated in an umbrella, and without affecting basic specifications such as strength, etc.

allows the volume of the folded umbrella to be reduced as compared with known umbrellas of the same general sort.

According to the invention there is provided a foldable umbrella framework comprising a plurality of linkages spaced apart angularly around the axis of a central column, each said linkage comprising a main stretcher pivotally connected at one end to a lower boss slidable on said central column, an auxiliary stretcher pivotally connected at one end to an upper boss fixed to said central column and pivotally connected at its other end with said main stretcher at a position intermediate the ends of said main stretcher, a rib pivotally connected intermediate its ends with the end of said main stretcher remote from said first boss, said rib having an outer free end for attachment to the periphery of an umbrella cover and having, at its opposite end, a head pivotally connected with one end of a tension link pivotally connected at its opposite end with said auxiliary stretcher at a position intermediate the ends of the latter, the pivotal connection in any said linkage having pivotal axes all substantially parallel with one another and extending in a direction perpendicular with the axis of said central column, and wherein each said auxiliary stretcher comprises a relatively thin flat strip which, at least over a major part of the region between its pivotal connection with said upper boss and its pivotal connection with the respective tension link, lies in a plane which is displaced laterally from, but is parallel with, the general plane of pivotal movement of the remainder of the respective linkage, the arrangement being such that in the folded condition of the framework, at least adjacent said upper boss, there is an overlap, as viewed perpendicular with the general plane of pivotal movement of the respective linkage, between, on the one hand, the auxiliary stretcher and, on the other hand, the respective main stretcher, rib and tensioning link, whereby the framework, in the folded condition, is made radially compact in the region of said upper boss.

Embodiments of the invention, and for comparison, a comparable conventional umbrella structure, are described below, by way of example, with reference to the accompanying drawings, in which: FIGURE 1 is a perspective view showing part of a linkage forming part of the framework of a conventinal foldable umbrella; FIGURE 2 is a side elevation view of the framework of the umbrella of which the linkage of Figure 1 forms part, in a folded condition; FIGURE 3 is a perspective view similar to Figure 1 but showing part of a linkage forming part of the framework structure of a foldable umbrella embodying the present invention; FIGURE 4 is a side elevational view of the umbrella framework of which the linkage of Figure 3 forms part, in the folded condition of the umbrella;; FIGURE 5 is a perspective view similar to Figure 3 but showing a linkage forming part of a further embodiment of the invention; FIGURE 6A is a plan view of the upper boss of the umbrella framework of which the linkage of Figure 5 forms part; FIGURE 6B is a plan view of an upper boss such as used in a traditional umbrella; FIGURE 7 is a plan view of another form of upper boss forming part of a framework embodying the invention; FIGURE 8A is a perspective view of a conventional foldable umbrella in a folded condition; FIGURE 8B is a perspective view of a foldable umbrella embodying the invention, in a folded condition; FIGURE 9 is a perspective view of part of a linkage forming part of yet another form of framework embodying the invention, and FIGURES 1 OA to 1 OC illustrate in detail the structure of a joint forming part of the linkage of Figure 9.

Figures 1 and 2 illustrate why a conventional foldable umbrella is somewhat bulky in its folded condition and particularly why, in this condition, the diameter of the tail part, i.e. the part which affords the top and middle of the umbrella when erected is greater than in other regions. This is, in fact, due to the frame structure of the conventional foldable umbrella.Figure 1 is a perspective view of part of a linkage which is one of a plurality of such linkages in the umbrella framework, each said linkage being connected pivotally with a boss 1 5 at the upper end of a central shaft or column 16 of the umbrella, and being also pivotally connected with a lower boss (see Figure 2) slidable in known manner along the shaft 1 6. The various linkages such as that shown in Figure 1 are disposed at regular intervals around the axis of shaft 1 6.

Each linkage comprises a main stretcher 13 (shown only in part in Figure 1) which has a flattened lower end received in a respective radial slot in the lower boss and pivoted, by means of a ring encircling the lower boss, for pivotal movement in a radial plane which includes the axis of shaft 1 6.

At its other, upper, end the stretcher 13 is pivotally connected with a rib 14, at a position intermediate the ends of rib 14 but closely adjacent a head 121 formed at the end of rib 14 which is uppermost in Figure 1 and is radially innermost when the umbrella is opened. The other lower end of the rib 14 is, of course, attached to the skirt of the fabric cover of the umbrella, in the finished umbrella.

An auxiliary stretcher 11 is pivotally connected at one end, by a pivot 17, to a lug or plate 18 secured to the stretcher 13 intermediate the ends of the latter, the structure 11 having its upper end flattened and received in a radial slot in the upper boss 1 5 where it is likewise pivotally mounted, in the same way as the stretcher 13 in the lower boss, for pivotal movement in the same radial axially extending plane. A tension link 10, of round section, is pivotally connected at one end 1 OA with the head 121 and at its other end 1 OB at a position relatively close to, but spaced from the lower end of the stretcher. The stretcher 11, as indicated at 11 A, is, over most of its length, of channel section.

In each linkage, the stretchers 11, 1 3, rib 14 and tension link 10 all pivot in the same radial axially extending plane relative to the axis of shaft 1 6 so that when the umbrella is folded, as shown in Figure 2, in each linkage the respective components are substantially disposed at different radial positions. (Some saving of space may be effected by arranging for the link 10 to be received in the channel 11 A, but in principle the components are spaced apart radially.) The increase in the radial dimensions of the folded umbrella adjacent the tail end (i.e. in the region of boss 1 5) is aggravated by the fact that the heads 121 are arranged adjacent, but spaced radially outwardly from the upper boss 15.

As a result, the diameter of the folded umbrella in the region of the various head joints 12 is substantially greater than in the region of the various joints 18, thus making the tail part of the umbrella rather bulky as compared with the remainder. Especially in the case of folded up topless umbrella, the umbrella fabric is automatically folded into the tail part as the umbrella is closed, so that in this region the number of layers of fabric which may be piled and overlapped may be above 30, thus making the tail part even more-bulky.In general, when a separate jacket is provided for the umbrella, in the process of putting the folded umbrella into its jacket, the tail part is generally inserted first, into one end of a generally tubular jacket, which end, if the jacket is to fit the handle end of the umbrella closely is generally somewhat smaller than would allow such insertion conveniently, and insertion of the umbrella in its jacket is therefore inconvenient and time-consuming.

Referring to Figures 3 and 4, in which parts corresponding to parts in Figures 1 and 2 have references which are numerically higher by ten, in an embodiment of the invention each auxiliary stretcher 21 is made of steel sheet and is thinner than the conventional channelled auxiliary stretcher 11 (as shown in Figure 1).

Further, the auxiliary strut 21 is cranked in the region P adjacent its pivotal connection with the tension link 20 so that the portion 21 B extending from said pivotal connection with the link 20 to the pivotal connection with the main stretcher 23 lies in the radial, axial plane of pivotal movement of the stretcher 23, rib 24 and link 20, whilst the portion 21Aextending upwardly from region Plies in a plane which is parallel with, but offset from, the last-mentioned radial, axial plane. One side wall of the channel-section main stretcher 23 is bent away at P' to accommodate the cranked portion P when the umbrella is fully folded.

When the umbrella is folded up, the upper portion 21 A of each stretcher 21 lies alongside the respective stretcher 23, and the associated head 22 of the respective rib 24, i.e. is spaced therefrom in the circumferential direction relative to the axis of shaft 26 but disposed at substantially the same radial distance from the shaft 26. Thus, in the folded umbrella, the stretchers 23 (of which there are generally eight), alternate with the stretchers 21 around the circumference of the shaft 26, in the region of the tail end of the folded umbrella, so that the umbrella, in the region of the tail, is of lesser radial extent than the folded conventional umbrella of Figure 2.

A comparison of Figures 1-2 with Figures 3-4 (all drawn in the same scale) shows the relative compactness of the embodiment of Figures 3 and 4 when folded in relation to the conventional arrangements of Figures 1 and 2. In the embodiment of Figures 3 and 4, tension link 20 can be made in the form of a straight steel rod which need only be thick enough to hold the shape of the loops (not shown) at its ends for the pivotal connections with rib 24 and the auxiliary stretcher 21, thus making the volume of the tension link even smaller.

As shown in Figure 7 it is necessary for the upper boss 25 to be formed with a different arrangement of slots 25A-25A to accommodate the stretchers 21, as compared with an upper boss (such as shown in Figure 6B), for a conventional arrangement such as that of Figures 1 and 2. Thus, whereas in the conventional upper boss structure as shown in Figure 6B, the slots 15A extend radially and parallel with the shaft axis, along respective diametral planes L1-, the upper boss 25 is formed with slots 25A-25A which do not extend along the diametral planes L1-L4 but is spaced therefrom circumferentially, anti-clockwise as viewed in Figure 7.Therefore, as shown in Figure 3, the tail part 21T of each auxiliary stretcher 21 can be received in a respective slot 25 and yet can keep its original manufacturing straight form. As a result, there is no need of any additional bending of the tail parts 21 T of the various auxiliary stretchers 21 during manufacture, thus saving time and work.

However, if a conventional upper boss structure such as shown at 1 5 in Figure 6B is adopted, it is necessary for the extreme end portion of tail part 21 T of each auxiliary stretcher to be cranked so as to lie, at said end, in the respective radial plane again, in order to fit into the respective one of the channels 1 5A-1 5A. Therefore, it is feasible to adopt either the conventional upper boss 1 5 or the upper boss 25 of Figure 7, for the embodiment of Figures 3 and 4.

Figure 5, in which like parts to parts in Figure 3 have the same references, illustrates a variant embodiment which differs from that of Figure 3, in that each auxiliary stretcher 21 is replaced by a pair of auxiliary stretchers 211 and 212 which extend generally parallel to each other.

In the region between the pivotal connection 31 with the main stretcher 23 and the pivotal connection 30 with the tension link 20, the respective portions 211 B and 21 2B of the two auxiliary stretchers lie in parallel planes which are relatively close together, the portions 211 B and 21 2B receiving between them the respective end of the link 20 and a plate 32 via which is made the pivotal connection with the stretcher 23.

Over the respective regions P and 0 extending upwardly from the region of the pivotal connection with link 30, the stretchers 211 B and 21 2B diverge upwardly, while over upper portions 211 A and 21 2A of the two stretchers, extending upwardly from the divergent portions, the stretchers 211 and 212 extend in parallel planes which are offset, relative to the respective lower portions 211 B and 212B, from the respective radial pivotal plane, and are thus spaced apart relatively widely as compared with said lower portions. The walls of the channel-section stretcher 23 are bent inwardly at P' and Q', to accommodate the portions P and 0 when the umbrella is folded. These two parallel auxiliary stretchers 211 and 212 thus form a "Y" shape together.Tension link 20 disposed between auxiliary stretchers 211 and 212 is pivotally connected therewith by rivet 30. Additionally, the lower ends of auxiliary stretchers 211 and 212 are pivotally connected by another rivet 31 with the plate 32.

When the umbrella is folded, the upper end portion of each stretcher 23, and the adjoining head 22 of the respective rib 22 are received between the two auxiliary stretchers of the respective pair.

In the variant to which Figure 5 relates, as there is a pair of auxiliary stretchers 211 and 212 for each main stretcher, a slight change must be made in the upper boss structure as compared, for example, with that shown in Figure 6A. Thus, in an upper boss in the embodiment of Figure 5, eight pairs of slots are formed around the boss extending inwardly from the circumference thereof and parallel with the axis of the umbrella shaft.

The pairs of slots, such as 351 A, 352A, are arranged at regular intervals around the shaft axis, the slots of each pair being disposed parallel with and spaced equally from a respective diametral plane L1 to L4 containing the shaft axis, each slot 351 A, 352A receiving a respective end 21 1T, 21 2T of the respective pair of auxiliary stretchers.

In the embodiment of Figure 3, as in the structure of Figure 1 , the main stretcher is of channel section, with the open side of the channel facing, in the folded condition of the umbrella, towards the umbrella shaft. Furthermore, in both of these structures, the pivotal connection with the lower end of the auxiliary structure is effected by means of a U-section bracket 1 8 fixed in the channel of the main stretcher and receiving, between its arms, the ends of the auxiliary stretcher.In this respect, the embodiment of Figure 5 differs only in that a member providing a single plate 32 received between the two stretchers 211, 21 2, is used instead of a U-section member 18, but this is once again fixed in the channel of a main stretcher of channel section which is open towards the umbrella shaft in the folded umbrella. However, a variant of Figure 5, shown in Figure 9, is different in this regard. As shown in Figure 9, lower ends of two auxiliary stretchers 211 and 212 receive between them a plate 32 to which stretchers 211 and 212 are pivotally connected by means of a rivet 31, the plate 32 being carried by the main stretcher 23. In this variant, the length of plate 32 is greater than that of the conventional plate 18, and the way in which the plate is connected with the main stretcher 23 is also different.In the variant of Figure 9, the main stretcher 23 is again of channel-section but is so arranged that the channel is open radially outwardly when the umbrella is folded up. As shown in detail in Figure 1 OA, two longitudinally extending, longitudinally aligned slots 231 and 232 are provided in the bottom of the stretcher channel, a web 233 separating the slots 231 and 232 (and thus minimising weakening of stretcher 23).

Plate 32 has a shorter part 321 with a rebate 321 A on its underside and a longer part 322 with a finger 322A extending longitudinally from its lower edge, and between these two parts, there is a transverse slot 323, shown in Figure 1 OB, which extends from the upper edge of the plate. During assembly, the shorter part 321 is extended lengthwise through the shorter slot 231, from the open side of the stretcher channel and then the longer part 322 is swung into the channel to pass through the longer channel 232, while the web 233 enters the slot 323 (see Figure 1 OB). In the fully inserted position (see Figure 1 OC) the bottom surface of the rebate 321 A in shorter part 321, lies along the outside 235 of the channel base, while finger part 322A of the longer part 322 lies along the inside 23N of the channel base.

The auxiliary stretchers 211, 21 2 are pivotally connected by rivet 31 to the longer part 322 of plate 32 as shown in Figure 1 OC. When auxiliary stretchers 211,212 pivotally rotate during folding the umbrella, shorter part 321 of joint 32 is caught and stopped at outer surface 23S of stretcher 23, while finger part 322A of longer part 322 is caught and stopped on inner surface 23N of stretcher 23. Conversely, if auxiliary stretchers, 211, 212 pivotally rotate during opening of the umbrella, the closed end 323A of slot 323 in plate 32 is caught and stopped on the bottom surface of web 233, so that plate 32 is effectively fixed to the main stretcher. In this variant structure, the plate 32 serves as a guide for positively guiding auxiliary stretchers 211 and 212 during unfolding and folding of the umbrella, especially during folding.Thus free play at the pivotal connection point will never increase to the extent of dislocation due to excessive looseness.

Figures 8A and 8B show respectively, in the folded condition, a complete umbrella utilizing the conventional framework of Figures 1 and 2, and a complete umbrella utilising a framework according to any of Figures 3 to 10. Considering the conventional umbrella, it will be noted that the diameter A2 of the framework at the tail of the folded umbrella is greater than the diameter A4 of the framework at a position midway between the ends of the umbrella, and that the radial thickness (T1) of the layers of cloth at the tail is twice that (T3) at said midway position. This is because in the fabric covering, before rolling up but after folding (as represented by broken lines in Figure 8A) there are four layers of cloth in the zone marked U, but only two layers of cloth in the zone marked L.

Thus, A1, the overall diameter at the tail of the folded and rolled umbrella, will be substantially greater than A3, the overall diameter at the midway position (A, = A2 + 2T,: A3=A4+2T3).

Considering the embodiment of Figure 8B, it will be noted that B2, the framework diameter at the tail end, is smaller than B4, the framework diameter midway along the folded umbrella, so that even though the fabric thickness at the tail (T2) is again twice the fabric thickness (T4) midway along the folded and rolled umbrella, the overall diameter (B,) at the tail is no greater than the overall diameter (B3) midway along the umbrella (B, = B2 + 2T2; B3 = B4 + 2T4). From Figures 8A and 8B, A3 is roughly equal to B3, while A, is larger than B,.

It will be noted that in each of the embodiments of the invention described, in the folded condition of the umbrella, the head joints (c.f. the head joints 221 in Figure 4) are spaced below the upper boss 25 along the axis of the shaft, whereas in the conventional arrangement shown in Figure 2, the head joints 121, in the folded umbrella, lie in the same axial zone as the upper boss 1 5 and are spaced radially outwardly therefrom. As a result, the radial dimensions of these folded umbrellas embodying the invention are further reduced at the tail end, as compared with the conventional folding umbrella of Figures 1 and 2.

Claims (14)

1. A foldable umbrella framework comprising a plurality of linkages spaced apart angularly around the axis of a central column, each said linkage comprising a main stretcher pivotally connected at one end to a lower boss slidable on said central column, an auxiliary stretcher pivotally connected at one end to an upper boss fixed to said central column and pivotally connected at its other end with said main stretcher at a position intermediate the ends of said main stretcher, a rib pivotally connected intermediate its ends with the end of said main stretcher remote from said first boss, said rib having an outer free end for attachment to the periphery of an umbrella cover and having, at its opposite end, a head pivotally connected with one end of a tension link pivotally connected at its opposite end with said auxiliary stretcher at a position intermediate the ends of the latter, the pivotal connection in any said linkage having pivotal axes all substantially parallel with one another and extending in a direction perpendicular with the axis of said central column, and wherein each said auxiliary stretcher comprises a relatively thin flat strip which, at least over a major part of the region between its pivotal connection with said upper boss and its pivotal connection with the respective tension link, lies in a plane which is displaced laterally from, but is parallel with, the general plane of pivotal movement of the remainder of the respective linkage, the arrangement being such that in the folded condition of the framework, at least adjacent said upper boss, there is an overlap, as viewed perpendicular with the general plane of pivotal movement of the respective linkage, between, on the one hand, the auxiliary stretcher and, on the other hand, the respective main stretcher, rib and tensioning link, whereby the framework, in the folded condition, is made radially compact in the region of said upper boss.

2. An umbrella framework according to claim 1 wherein the respective plane of pivotal movement of the main stretcher, rib and tension link of each said linkage extends generally radially with respect to the central column, while the end portion of the respective auxiliary stretcher which is pivotally connected with said upper boss also lies in the respective said laterally displaced plane, the ends of said auxiliary stretcher pivotally connected with said upper boss being accommodated in slots extending into the latter from the periphery thereof, which slots are in respective planes which are not coincident with the respective said planes of movement of the respective linkages but are parallel with but displaced circumferentially therefrom.

3. An umbrella framework according to claim 1 wherein the end portions of said auxiliary ribs which are pivotally connected with said upper boss are bent from the respective said laterally displaced planes back into the respective radial planes and are engaged in respective radial axially extending slots in said upper boss.

4. An umbrella framework according to any preceding claim wherein the arrangement is such that, in the folded condition, the head of each said rib lies below the upper boss and at least partially within the radial span of the latter.

5. An umbrella framework according to any preceding claim, wherein each said linkage comprises a pair of said auxiliary stretchers, arranged to form a composite stretcher in which the stretchers of the pair are disposed relatively close together and parallel with one another over the zone from the pivotal connection with the respective main stretcher to the region of the pivotal connection with the respective tension link, and diverge over a short distance from said zone to a further zone over which the stretchers of the pair again extend parallel with one another, at a relatively wider spacing, to the upper boss, the stretchers of said pair lying on opposite sides of the joint with the respective main stretcher and of the joint with the respective tension link.

6. An umbrella framework according to claim 5 wherein, for each said pair of auxiliary stretchers, the upper boss is provided with a respective pair of parallel slots extending inwardly from the periphery of said upper boss and parallel with the axis of said main column, each said pair of slots receiving the ends of a respective said pair of auxiliary stretchers, one said stretcher to each slot, the slots of each pair being spaced circumferentially from, on either side of, and parallel with the radial axial plane of movement of the remainder of the respective linkage.

7. An umbrella framework according to claim 5 or claim 6 wherein each said main stretcher is in the form of a channel-section member, and is pivotally connected with the respective pair of auxiliary stretchers by a joint piece disposed on the base of the channel, on the outside thereof.

8. An umbrella framework according to claim 7 wherein each said joint piece is in the form of an elongate flat plate having intermediate its ends a slot extending transversely from one longitudinal edge of the plate, partially across the plate, and dividing the plate into a longer and a shorter part, the plate having, on its edge opposite that from which said slot extends, a rebate extending from the end of said shorter part, and a finger extending, in the longitudinal direction of the plate, from said longer part, and wherein the base of the channel of the respective channel section main stretcher is provided with a shorter and a longer slot extending in line with one another and separated by a bridge part, said plate being fitted into said slots from the channel, so that said longer part projects through said longer slot, and said shorter part projects through said longer slot, and said shorter part projects through said shorter slot, with said slot in the plate receiving said bridge part and said finger engaging the internal surface of the base of the channel, said pair of auxiliary stretchers being pivotally connected with the projecting portion of said longer part of said plate.

9. An umbrella framework, substantially as hereinbefore described with reference to and as shown in Figures 3 and 4 of the accompanying drawings.

10. An umbrella framework substantially as hereinbefore described with reference to and as shown in Figure 5 and Figure 6 of the accompanying drawings.

11. An umbrella framework substantially as hereinbefore described with reference to and as shown in Figure 9 and 1 OA to 1 OC of the accompanying drawings.

12. An umbrella incorporating an umbrella framework according to any preceding claim.

1 3. An umbrella substantially as hereinbefore described with reference to and as shown in, Figure 8B of the accompanying drawings.

14. Any novel feature or combination of features described herein.