Balustrades

Abstract: A balustrade is proposed wherein a hingedevice (66) connects each baluster (56) to the rail (55) in such manner as to permit limited pivotal and translational movement therebetween. The hinge device (66) comprises a flat spring of generally J-shape, the elongate body (67) of the spring being secured to the rail and the curved end (68) of the spring being secured to the baluster. An inflexible plate (70) overlies the body (67) to restrain the same against movement. Opening of the curved end (68) permits relative pivotal and translational motion between the baluster (56) and rail (55). The arrangement offers advantages in collapse of the balustrade for transportation purposes and also permits of adjustment of the angle between the rail and balusters to accommodate facture and other tolerances.

Description: This invention relates to a balustrade, particularly but, not exclusively, for domestic use. In European Patent No. 246057 there is described a balustrade which includes hand and base rails interconnected by a plurality of balusters. The balusters are pivotally connected to the rails and this offers very significant advantages in the manufacture, transportation and installation of such balustrades. For example, it is possible for the entire balustrade to be manufactured under factory conditions, leading to higher quality and less possibility of damage due to poor site conditions and perhaps inferior labour. Further, because of its pivotable nature the entire balustrade can be collapsed to a position wherein the two rails are close together and the balusters are disposed nearly parallel thereto. This provides a very compact package enabling storage, transportation and packaging costs to be reduced. There is the further advantage (described in the specification) that the balustrade can be arranged to fit stairs of slightly varying height and pitch simply by varying the inclination of the rails, whilst always maintaining the balusters vertical. By leaving slightly extra material at the ends of the two rails the only operation needed on site, once the newal posts have been positioned, is the transverse cutting of the two rails to fit the post. This is an operation which can be carried out accurately on site. The aforementioned patent also describes how the invention is applicable principally to balustrades made out of wood or comparable materials such as moulded plastics material or composite materials which do not have thin section strength as do metal balustrades. There is much prior art (for example exemplified by U.S. Patent No. 3174727 to Burt) which describes a pivotal connection between a rail and a baluster in a metal balustrade. Because metal is inherently much stronger than wood, the provision of a pivotal connection between metal balusters and metal rails is very easy, particularly if the metal rail is a hollow section. However, a comparison of the problem of machining wood to such tolerances and the necessary thicknesses and strength which would be required make it quite clear that the methods and constructions of Burt and the like are quite unsuitable for use in relation to wooden balustrades. There is the further disadvantage in the construction described in Burt and, indeed, almost all the metal constructions and many of the old wooden constructions, in that, although the pivoting mechanism can very often be effectively shielded from view by being disposed wholly or partly in the underside of the handrail, the pivot mechanism on the lower rail is exposed. This can be unsightly and is undesirable in a domestic environment. A further disadvantage is that the lower rail very often has to be provided with cavities in its upper surface to accommodate either fastenings or the lower ends of the balusters. As such cavities are upwardly open, they tend to collect finishing material such as varnish or waxes. In use they become reservoirs for dirt and dust and can become most unattractive. The invention described in the aforementioned patent EP-A-246057 did avoid this problem, but the connection between the balusters and the rails in that earlier patent did have certain disadvantages. Fig. 1 is a schematic side elevation of a balustrade 10 on a stair 11. The balustrade 10 has a hand rail 12 and base rail 13 pivotally interconnected by balusters. To the left of Fig. 1 are shown balusters 14 pivoted by the means described in EP-A-2460517. It will be seen that the end of each baluster is part cylindrical and effectively makes only line contact with the rails 12 and 13. Whilst the interconnecting devices which allow such pivoting are strong and effective, the apparent point contact which is visible at 15 in Fig. 1 is found in many cases to be aesthetically unattractive. A balustrade which has such apparent point contact appears, to the purchaser, to be more flimsy or fragile than a conventional balustrade wherein an impression of extra strength is given by the fact that the ends of the balusters are (or appear to be) fully housed within the rails. It is an object of the present invention, therefore, to provide a balustrade which is a further improvement over and above the balustrade of the aforementioned patent. The invention provides a balustrade which includes a hand rail and a base rail interconnected by a plurality of parallel balusters, each end of each baluster being pivotally attached to its respective rail by a pivot arrangement which includes a socket in the rail adapted closely to surround and receive an end portion of the baluster and a hinge device connecting the baluster end to the rail wherein the hinge device comprises a first part securable to the baluster and a second part securable to the rail, the first and second parts being pivotally connected together such that the baluster and the rail are relatively pivotally movable about an axis extending transversely of the rail and baluster the hinge comprising a spring so that said end portion of the baluster is translationally movable into and out of said socket. The invention provides, as a further feature, a baluster/rail connecting device including a first part adapted to be connected to the baluster and a second part adapted to be connected to the rail, characterised in that the connecting device comprises a spring having an elongate body forming the second part and a curved head forming the first part, the free end of the curved head adapted to be secured to a baluster whereby the baluster is pivotable about an axis substantially transverse to the rail and the baluster is also movable axially towards and away from the rail. Preferably each part is adapted to be essentially a push-fit in its component. The socket in the appropriate surface of the rail can be such as to suit the baluster. Normally the top and bottom ends of the baluster (even if turned) will be left rectangular. In the past this has been done to improve connection between the baluster and the rail and therefore has become aesthetically accepted. In this case the sockets will be rectangular. However, the invention works equally well with non-rectangular balusters, for example circular balusters which could be accommodated within circular sockets. For accommodation in the socket the end of each baluster will be provided with an angled face. The part of the baluster which is nearest the acute angle between the face and the length of the baluster will have to be chamfered so as to fit snugly within the socket. In the case of a non-rectangular baluster such chamfering will need to be progressive around the upper side of the baluster. The invention will be described further, by way of example, with reference to the accompanying drawings wherein:- Fig. 1 is a schematic side elevation showing a composite baluster, the left-hand part illustrating a known baluster and the right-hand part illustrating either a conventional non-adjustable fixed baluster or a baluster in accordance with the present invention; Fig. 2 is a side elevation illustrating a form of connection between a baluster and the rail in a balustrade; Fig. 3 is a comparable view to that of Fig. 2 illustrating a landing balustrade; Fig. 4 illustrates the pivot arrangement and the spring; Fig. 5 is a side elevation of the spring; Fig. 6 is a front elevation of the spring; and Fig. 7 is a vertical cross-section through the baluster of Fig. 2. Referring now to Figs. 2 to 6, preferred balustrade 54 of the invention (Fig. 2) includes a pair of rails, of which only the hand rail is illustrated at 55, and a plurality of ballusters 56 extending between the two rails. Each end of each balluster 56 is connected to its respective rail by a pivot assembly and the pivot assembly will be described in relation only to one connection, namely that between baluster 56 and hand rail 55, it being understood that the other connections are comparable. In Fig. 2 the balluster 56 shown is part of a sloping balustrade. Its upper end 57 is provided with an angled end face 58. The hand rail 55 is provided with a plurality of generally rectangular recesses 59 which are formed in a groove which extends longitudinally of the inner face of the hand rail and which is divided up by spacers 60. The upper end of each spacer 60 is chamfered on its interior edge at 61 to create a generally triangular recess 82. The outer edge of the spacer 60 at the upper end thereof provides a fulcrum, at point 62, which engages with the face 63 of the baluster 56. The opposite face 64 and the surface 58 terminate at and are joined by a transition surface 65 which is cylindrical about point 62. To allow the end 57 of the balluster to pivot relative to the rail 55 and alsoto effect translational motion relative thereto into and out of the recess 59, a spring pivot device 66 is provided. Spring pivot device 66 is generally J-shaped in side view, and has an elongate body 67 and a curved head 68. The free end of head 68 is secured at 69 to the upper end of face 63. To constrain movement of the body 67 of spring pivot device 66 an inflexible plate 70 sandwiches the body 67 against the base of a channel 59 a in the base of the recess 59. A common fastener 71 secures plate 70 and spring pivot device 66. In use, the baluster 56 can pivot between the position shown in full in Fig. 2 and the position shown in dotted lines therein, for storage and transportation. In use, the spring (to be described in detail later) allows movement of the baluster ends relative to the recesses 59 such as to allow variation in the balustrade angle from perhaps 38° to 42°, ample to accommodate facture and other tolerances. Of course, in different applications different angles can be chosen. Fig. 3 illustrates a slight variation wherein a foldable balustrade is to be provided for a landing or the like. Here, the balusters 72 have to be at right angles to the rail 73 and although the spacers 74 and the pivot arrangement including the spring 56 are the same, the upper face 75 of the baluster extends at right angles to the longitudinal axis of the baluster. In other respects the operation and function of the embodiment shown in Fig.3 is analogous to that illustrated in Fig. 2. Figs. 4, 5 and 6 show the pivot arrangement, including the spring pivot device 66 in more detail. The dimensions shown in Fig. 5 are in millimetres and illustrate a typical spring suitable for use with a domestic balustrade rising perhaps some 9 feet and having balusters approximately 35mm square or comparable size. The spring is approximately 0.5mm in thickness and is made from CS70 spring steel. This is adequate to allow the head 68 to wind and unwind to allow relative movement between the balusters and rails whilst maintaining a firm interconnection between them. It will be seen that at the end of the head 68 the spring is provided with a pair of outwardly extending lugs which have apertures 76 whereby the spring can be secured to the balustrade. Of course, other fastener means are possible. In particular, instead of the screws shown at 69 and 71, push-in fitments engageable by friction and/or adhesive within sockets bored into the material of the balusters can be advantageous and lead to easier assembly. The spacers will normally be applied after the springs have been attached to the rails. The embodiments herein described overcome the problem of providing a decorative, aesthetically pleasing balustrade wherein the ends of the balusters are housed within the rails, and where no open catchments are provided for dust or the like. The balustrade has all the appearance of a conventional rigid balustrade but has the advantages of minor adjustability for installation under varying conditions of the surroundings and also almost total folding for ease of storage, packaging and transportation. The invention is not limited to the precise details of the foregoing and variations can be made thereto within the scope of the invention.

Claims: A balustrade (54) including a hand rail (55) and a base rail interconnected by a plurality of parallel balusters (56), each end of each baluster being pivotally attached to its respective rail by a pivot arrangement which includes a socket (59) in the rail adapted closely to surround and receive an end portion of the baluster and a hinge device (66) connecting the baluster end to the rail, wherein the hinge device comprises a first part (68) securable to the baluster and a second part (67) securable to the rail, the first and second parts being such that the baluster and the rail are relatively pivotally movable about an axis extending transversely of the rail and baluster, characterised in that the hinge device comprises a spring so that said end portion of the baluster is translationally movable into and out of said socket. A balustrade as claimed in claim 1, wherein the spring is J-shaped, said first part comprising an end of the curve (68) of the spring and said second part comprising longer body (67) of the spring. A balustrade as claimed in claim 2, wherein an inflexible plate (70) overlies the said longer body (67) of the spring (66) to constrain movement thereof. A balustrade as claimed in any one of the preceding claims, wherein the end of the baluster is a close fit in its respective socket and the end of the baluster is arcuately chamfered at that edge thereof remote from the axis of pivotal motion between the baluster and rail. A balustrade as claimed in any of the preceding claims, wherein the end face of the baluster is inclined to accord approximately to the angle between the baluster and rail in the erected condition of the balustrade. A balustrade as claimed in any one of the preceding claims, wherein the sockets and the ends of the balusters are of rectangular form. A baluster/rail connecting device including a first part (68) adapted to be connected to the baluster (56) and a second part (67) adapted to be connected to the rail (55) characterised in that the connecting device comprises a spring having an elongate body forming the second part and a curved head forming the first part, the free end of the curved head adapted to be secured to a baluster whereby the baluster is pivotable about an axis substantially transverse to the rail and the baluster is also movable axially towards and away from the rail. A baluster/rail connecting device as claimed in claim 7, wherein each part is a push-fit in its component.

Inventors: TURNER JACK, TURNER, JACK
Applicants: NORTHERN JOINERY LTD, THE NORTHERN JOINERY LIMITED
Application year: 1992
Main classification: E04F11
IPC codes: E04F11