WO2017108997A1

WO2017108997A1 - Adjustable frameworks

Info

Publication number: WO2017108997A1
Application number: PCT/EP2016/082249
Authority: WO
Inventors: Marta JORDAN
Original assignee: Raise Design Ltd
Priority date: 2015-12-21
Filing date: 2016-12-21
Publication date: 2017-06-29
Also published as: GB201522570D0

Abstract

A foldable framework is disclosed, with a base member (1) and an upper support member (2). Legs (3,4,5) extend between the base member (1) and the upper support member (2). The legs (3,4,5) are fitted to the base and support members at the vertices of an equilateral polygon such as a triangle and are joined to at least one of the base (1) and upper support (2) at the location points via ball joints (8). At least one of the ball joints comprises an enclosure surrounding a ball having a laterally projecting portion connected to the leg. The enclosure wall is configured to define a track for the portion of the leg projecting from the ball. When folded, the legs lie between the base and support members. The framework is erected by turning the base relative to the top, during which the legs move to, and then past, being perpendicular to the planes of the base (1) and top (2). The framework may be folded e.g. for storage, by reversing the turning movement.

Description

ADJUSTABLE FRAMEWORKS

This invention relates to adjustable frameworks, in particular for providing elevated support surfaces for a wide variety of uses, wherein one part of the framework is designed to constitute or rest on a base, e.g. being or resting on a floor, and the other part is designed to constitute, or to support, a generally horizontal upper support surface.

Such support arrangements find use in a very wide variety of applications, for example tables, desks, stools, benches, display stands and the like. It is highly desirable for such units to be movable from a collapsed position where the framework is at minimum height to an extended position where the distance between the base portion and the support portion is at or near a maximum level.

Published Patent Specification SE 504944 C2 discloses a support framework consisting of a triangular base portion, a triangular support portion and three hydraulic ram members serving as legs and jointed to the base and support portions at their respective ends by means of ball joints. The system there described requires a source of hydraulic power for its operation and is complex and expensive to manufacture.

According to the present invention, there is provided a foldable framework comprising a base member and an upper support member and a plurality of legs, each extending between a location on the base member and a location on the upper support member, where the positions of the locations on the base and support members respectively are at the vertices of an equilateral polygon, the length of each leg is less than the side length of the respective polygon and where the legs are joined to at least one of the base and upper members at the location points via ball joints, and wherein at least one of the ball joints comprises an enclosure surrounding a ball having a laterally projecting portion connected to the leg and wherein the enclosure wall is configured to define a track for the portion projecting from the ball which enables the leg to be moved from a position almost in the plane of the base and support members to, and then past, a position in which each leg is perpendicular to the plane of the base or support member, and then to be held at an angle to that plane.

The base and upper support surface of the framework may be made up entirely of elongate members linked to one another to form the base and upper support surface with these two being held together by the legs. For many applications, however, both the base and the upper support surface will be made of flat sheet material on to which the socket(s) for the ball joints are mounted. The base and upper support surfaces, in such a case, may have an identical outer shape and size so that they stack when the structure is folded or collapsed, with a space between them accommodating the legs. One or other or both may have a peripheral skirt or rim to enclose the legs fully when the framework is folded. Alternatively, provided there is sufficient clearance to allow for the twisting as the framework is deployed, one of the base and upper support surface may nest inside the other. This enables a structure to be incorporated into a floor with its top flush with the remainder of the floor when the structure is folded or collapsed.

Preferably the equilateral polygon is an equilateral triangle, a square or a regular pentagon or hexagon. Preferably at least half of the ball joints have a track restricting the path of movement of a leg located therein. Preferably the legs are joined to both of the members by ball joints, though, if desired, some may be replaced by other joints allowing the movement to occur, e.g. two linked rings.

As the base member and support member are moved apart, because they are fixed to the legs, the legs move from a position where they lie at an acute angle to the planes of the base member and support surface member through to a position perpendicular to the plane of each, at which point the base and support surface member are at their maximum distance from one another, and which, by moving a little further rotating the base member and support surface member relative to one another, the legs may be moved so that they lie at a slight angle from the vertical and, because of the shape of the track in the ball joint(s), cannot move further.

Such a structure may be rapidly erected from the folded or collapsed condition by twisting the base member relative to the support member. As this takes place, the base member and support member move from being adjacent to being held apart by the legs, to a position where the support member lies above the base member by a certain height, the maximum height corresponding to the length of the legs. The twisting movement may be achieved by grasping the support member and twisting it while lifting it up, or the support member may be lifted enabling the base member to rotate as the support member is lifted, and if the lifting is sufficiently fast, the

momentum of the base member carries it past the point at which the legs are vertical, and the erected structure can simply be rested on the floor or other horizontal surface such as a tabletop. If the base member is itself fixed in position, for example constituting a floor of a room or decking on a balcony or patio, then the upper support member needs to be turned about a vertical axis as it is lifted. This may be achieved by a simple vertical lifting movement if the upper support member is freely rotatably mounted on the underside of a support surface; when that support surface is lifted, the upper support member of the foldable framework rotates beneath it. Alternatively, the base member may be mounted so that it can rotate about a vertical axis as the upper support surface is lifted, e.g. by being set on a circular fixed track in a floor. The upper support member may itself act as a base member in an extended framework, i.e. it may carry a second upper support member so as to produce a "two-decker" framework. This enables the upper support surface formed by the second upper support member to be essentially at twice the height from the horizontal surface, such as the ground or a floor on which the two-decker framework is set, as the intermediate member which has a dual function, constituting the upper support member of the lower framework and the base member of the upper framework. A three or even four decker arrangement can be produced analogously if it is desired to produce a taller, relatively narrow overall structure, such as a lectern or projector stand, which still has a relatively small "footprint". Multiple arrangements of this sort do not even have to have successive support surfaces of the same size as one another: for example, a set of discs of decreasing size (which may even nest each in the one below it when the structure is folded), may produce an easily erected multi-shelf merchandiser or a conical "Christmas tree" one.

In its simplest version, accordingly, the present invention provides framework structures which can be expanded from a folded position where they take up little space to an extended position where they can act as a support surface, e.g. to hold something above a floor. A series of such structures may enable the uppermost support surface to be rapidly erected to provide a raised horizontal support surface which is stable in use but where the structure can be easily collapsed by rotating the topmost support surface relative to the base member in the opposite direction to that needed to raise the support member.

If desired, means may be provided to enable the base member and support member parts of the framework to be fixed or locked at a given distance from one another. One way of achieving this is to provide a mechanism which can vary the effective position of the end of the track in the ball joint(s), e.g. with an outer rotatable cap restricting the track. An alternative is to provide, pivoted to one of the legs, a strut or like member which can be swung out and engaged in a suitable socket located in a fixed position relative to or on the base member or upper support member. If desired, spring members may be fitted, pivotally connected between the base and/or support surface members and the legs, to assist in moving the structure from a folded to an erected position. Small gas springs may be used. In such a case, means need to be provided to lock or hold the base and support surface together when the structure is in the folded condition.

For many uses, the base member and support surface will be themselves of regular polygonal shape, and this has the advantage that when the unit is in its collapsed or folded position, the two polygonal shapes may match. When erect, they will be offset slightly. They will match only as the legs are at right angles to the planes of the base and upper support members, at which point the upper support member will be at its maximum separation from the base member; this separation is be reduced as each leg reaches the end of its range of movement as defined by the track, at which point the framework is stable and can act as a support structure. The offset is unnoticeable if one or both of the base and upper support members is circular.

The invention is illustrated by way of example with reference to the accompanying drawings in which:

Figures 1 to 5 are diagrammatic views of a structure in accordance with the present invention as it is moved from folded (Figure 1 ) to fully extended condition, where Figures 2 and 3 show the intermediate positions of the parts of the framework as it is erected, and Figures 4 and 5 are perspective and top views of the unit in its erected position;

Figures 6A to 6D show diagrammatically the movement of a leg in a ball joint base, these corresponding to the fully-folded position of the unit, i.e. that shown in Figure 1 and Figure 6A, up to the most extended position where the base member and support surface are furthest apart, as shown in Figure 3 and Figure 6C, and to the final self-supporting extended position shown in Figure 4 which corresponds to the position adopted in Figure 6D; Figure 7 is an exploded view showing the detailed construction of part of a ball and socket joint; Figures 8A to 8H show a modified form of the ball joint as in Figures 6A to 6D but with a locking cover; and

Figures 9A, 9B and 9C show a modified form of ball joint with a locking cover.

Although the framework will work if only one of the legs is provided with a ball joint type shown in detail in Figures 6A to 6D, it is preferred that all of the ball joints are of the same construction so as to share the load evenly between themselves when, in use, the upper surface extended from the base member is loaded by placing something on it.

Alternatively, the ball and socket joints adjacent one of the base and support members are of the restricted track variety shown in Figure 6, while the other ball and socket joints adjacent the other of the base and support members units are all simple ball and socket joints allowing relatively unrestricted movement.

As shown in Figures 1 to 5, the basic construction of the unit consists of a triangular base member 1 , a support surface member 2, and three struts or legs 3, 4, 5. As shown in Figures 2 to 4, the lower end of each leg 3, 4, 5 carries a ball and the ball and socket joint is formed by locating the ball in a seating 8 set on the base member 1 . As can be seen by looking at Figure 6, the base of each ball joint may be secured to the floor of base member 1 by means of screw-threaded holes 9 engaging with threaded bolts 10 passing through the floor of base member 1 . The socket portions on the underneath of the support surface member 2 may be formed likewise or may simply be in the form of a ball joint base with a spherical seating for the receipt of the ball shaped projection on the upper end of each leg.

Figure 7 shows in greater detail one way of constructing the ball joint arrangement on the base member 1 . As shown in Figure 7, the housing in which the ball at the end of a leg is held captive, is in two parts. A base part 17 is fixed to the floor of member 1 by means of a central bolt 18 which passes through a hole 15 in the floor of member 1 . A second hole 1 6 is present in the floor into which an alignment peg 14 projecting from base part 17 fits in order to secure the correct angular position for that part. The ball is held captive when the joint is assembled by means of a cap piece 19 which is fixed to base 17 by means of three screws which engage with threaded holes in three upstanding bosses 20, 21 and 22. The ball joint arrangement shown in Figure 7 has a track in cap piece 19 which determines the maximum extent to which a leg connected to it can go past the vertical as the support member is raised. If desired, the track may be extended somewhat further than shown, or reduced. Referring now to Figure 8, this shows diagrammatically a ball joint similar to that shown in Figures 6A to 6D, but where the seating 8 is surrounded by a rotatable cap 12 having a contoured slot in it which enables the structure to be folded or collapsed when the slot is aligned with the track in seating 8, as shown in full lines in Figure 8D. The position of the leg 3 when the structure is folded is shown in dotted lines in Figure 8D. The cap 12 is rotatable on seating 8 about a vertical axis and the contoured slot in it is arranged so that, as the cap 12 is turned, the effective length of the track is limited, i.e. the leg comes to rest against the edge of the slot in cap 12 and the end of the track in seating 8. By rotating the cap 12 to its maximum extent, shown in Figure 8H leg 3 may be locked. Referring to Figure 9, this shows an alternative form of ball joint, where the base of the joint, denoted 29, is fixed via screws passing through holes in its periphery (one of which is visible in Figure 9C and denoted 28) to the base member. The base has a track and central spherical socket for the ball portion on the end of the leg 3. Set on the base 29 is a bell-shaped cover 31 which has four depending skirt portions which clip under the edge of the base. The bell-shaped cover has a slot 32 in it which can be aligned with the track in the base, as shown in Figures 9A and 9B, to allow the leg to move, but if the cover 31 is then twisted relative to the base, as shown in Figure 9C, after the structure has been erected, it locks the leg into position and must be twisted back when it is desired to fold or collapse the structure. The edges of the slot 32 fit into opposite sides of a circular groove 37 between the cylindrical portion of leg 3 and the ball on its end. The twisting of the cover 31 may be assisted by the use of a tool if needed to move the cover to a desired position, e.g. engaging between the skirt portions 30. Alternatively, the edge of cover 31 may be knurled, or the cover may have a pair of opposite projections, in either case to enable it to be turned more easily by hand.

As can be seen, the present invention provides a foldable support structure which can be easily deployed, which requires no external source of power to operate it, and which can be collapsed when not required after use into a neat and compact unit for storage. It can be produced in a range of sizes to suit its intended purpose.

Claims

1 . A foldable framework comprising a base member and an upper support member and a plurality of legs, each extending between a location on the base member and a location on the upper support member, where the positions of the locations on the base and support members respectively are at the vertices of an equilateral polygon, the length of each leg is less than the side length of the respective polygon and where the legs are joined to at least one of the base and upper members at the location points via ball joints, and wherein at least one of the ball joints comprises an enclosure surrounding a ball having a laterally projecting portion connected to the leg and wherein the enclosure wall is configured to define a track for the portion projecting from the ball which enables the leg to be moved from a position almost in the plane of the base and support members to, and then past, a position in which each leg is perpendicular to the plane of the base or support member, and then to be held at an angle to that plane.

2. A foldable framework according to Claim 1 wherein the equilateral polygon is an equilateral triangle.

3. A foldable framework according to Claim 1 or 2 wherein at least half of the ball joints have a track restricting the path of movement of a leg located therein.

4. A foldable framework according to any one of Claims 1 to 3 wherein all of the legs are joined to both of the members by ball joints.

5. A foldable framework according to any one of Claims 1 to 4 and including means to enable the base member and support member parts of the framework to be fixed or locked at a given distance from one another.

6. A foldable framework according to any one of Claims 1 to 5 wherein at least one of the base and upper support member is a sheet of material to which one or more base members for the ball joint(s) are mounted.