GB2191840A - Play structures - Google Patents

Abstract

In a play structure a half log (10) or the like is fastened to a support frame by a bolt (14) which co- operates with a nut element (4) held captive in a channel (2) forming part of the frame. The nut may have an enlarged head which engages behind channel flanges (3) and a spigot which projects through the channel mouth and enters the hole through the log to facilitate location. The head may have grooves which engage with the edges of flanges 3 to prevent rotation of the nut. A spring may hold the nut against said edges. <IMAGE>

Description

SPECIFICATION Play structures The invention relates to the construction of play structures.

Conventionally cladding members such as wooden logs or the like, are attached to a play structure frame by threaded bolts passed through aligned holes in the member and a limb of the frame structure, and secured by nuts. This method leaves the threaded end of the bolt and the nut exposed which can cause injury. In addition the holes must be made in the frame to register with those of the cladding members, which complicates assembly.

In order to overcome these problems the present invention provides a joint assembly for attaching a member to a support frame in a play structure, comprising an elongate frame part in the form of a channel, an internally threaded element engaged in the channel and retained thereby against disengagement through the channel mouth, and a bolt extending through a hole in the member and threadedly engaged with said element thereby clamping the member securely against the frame. With such a joint assembly the end of the bolt remote from the bolt head is wholly enclosed in the space defined by the channel of the frame, and as a result does not constitute a potential hazard to children using the play structure.

Preferably the threaded element, hereafter referred to as the "nut", is free to slide in the channel, but is prevented from rotating by engagement with the side walls of the channel.

The side walls of the channel may be turned inwards at their free edges to form flanges for keeping the nut captive in the channel. In one possible embodiment, the nut is adapted to be inserted through the channel mouth and in this case the nut may be biased away from the bottom of the channel by a spring to retain it in position prior to insertion of the bolt.

Grooves may be provided in the surface of the nut which co-operate with the edges of the channel flanges to assist positioning of the nut and preventing rotation when it has been inserted into the channel.

While the aforementioned spring biased nuts are satisfactory, inserting the nuts into the channels can be a lengthy task e.g. when large numbers of half logs are to be fastened to a support frame, especially in cold weather conditions. Difficulty can also arise in aligning the nuts with the bolts passing through the cladding members. These inconveniences tend to increase assembly time and hence the cost of erecting the play structure.

A preferred form of nut avoids these drawbacks and has a first part slidable in the channel and engageable therewith to prevent removal through the channel mouth, and a second part which protrudes outwardly through the channel mouth for co-operation with the cladding member, or the like, being fastened to the frame. The first nut part may be inserted into the channel through an open end of the channel. Alternatively the flanges of the channel may be interrupted over a short section, preferably adjacent an end thereof to allow insertion of said first nut part.

This has the advantage that the ends of the channel may be closed off e.g. by a mounting plate or another frame part before the nuts are inserted.

The invention may be fully understood from the following description of some embodiments reference being made to the accompanying drawings wherein: Figure 1 is an exploded perspective view showing a first joint assembly according to the invention; Figure 2 is a front view of a sub-frame for use in the play structure; Figure 3 is a view similar to that of Figure 1 and showing a second embodiment of the invention; and Figure 4 is an enlarged transverse crosssection through the channel and nut of the assembly illustrated in Figure 3; Referring to Figure 1 there is shown a section 2 of a limb of a play structure support frame. The limb is formed by a channel having the free edges of the side walls turned inwardly and downwardly to define retaining flanges 3.

A nut 4 of generally rectangular shape can be inserted into the channel with its longest sides parallel to the side walls of the channel.

The nut can then be rotated through 90" so that it is held in the channel by abutment with the inturned flanges 3. The nut has a coil spring 6 attached to its rear face and when the nut is positioned in the channel this spring 6 biases the nut against the inturned edges of the flanges 3. Grooves 8 in the surface of the nut co-operate with the flanges 3 and are provided with teeth to grip the flanges 3.

As shown the member to be fixed to the frame is a generally semi-cylindrical or half log 10. The log has a countersunk hole 12 through which a bolt 14 equipped with a washer 15 is passed. The bolt may be of any known type. However to prevent unwanted removal of the articles it is preferred to use bolts that require dedicated tools to unscrew them, such as the Resistorx bolthead illustrated. This has a head with a star-shaped recess in which there is a central pin. When the bolt is tightened into the nut 4 the log 10 is clamped firmly against the limb 2. The subframe shown in Figure 2 has crosspieces 16, 18 fixed e.g. by welding, to upright members 20, 22. The crosspieces are channel shaped limbs of the form described with reference to Figure 1. The upright members 20, 22 are fixed to an L-section base member.End mounting plates 24, 26 are mounted on cylindrical tube sections 28, 30 fixed to the sides of upright members opposite the crosspiece 16. The sub-frame can support a series of essentially parallel logs 10. Each log is fastened firmly to each of the crosspieces 16, 18 by a joint assembly as shown in Figure 1.

It will be appreciated that all the securing nuts and the ends of the bolts engaged therewith will be enclosed by the channel crosspieces 16, 18. Consequently they do not present any risk of injury and are inaccessible so that unauthorised removal of the logs 10 is made more difficult. It should also be mentioned that the positional adjustment permitted for the nuts in the crosspieces facilitates assembly by providing some compensation for variations in the positions of the holes in the logs.

In an alternative construction (not shown) the end mounting plates 24, 26 are connected directly to the ends of the crosspieces, so that the crosspieces can be bolted on to the upright members. In either construction the upright members 20, 22 can be rectangular hollow sections provided with holes at the positions where the crosspieces are to be mounted. Internally threaded collars fitted into the mounting holes can receive the crosspiece attachment bolts.

Referring now to Figures 3 and 4, in which the same reference numerals have been used to designate corresponding parts as those used in Figures 1 and 2, a channel 2 of a play structure support frame has a mounting plate 24 attached by welding at one end thereof.

For a short section adjacent the plate 24 the flanges 3 of the channel are removed to provide an opening 7 for inserting nuts 4 into the channel. The mounting plate 24 is fixed e.g. by bolting or welding, to another frame member, here shown as upright member 22.

A similar mounting plate (not shown) is attached to the other end of the limb 2.

The nuts each comprise a generally rectangular head or flange portion 4a and a spigot portion 4b having a threaded bore 5. The head is restrained from displacement out of the channel mouth by the inturned flanges 3 of the channel side walls, as clearly seen in Figure 4. The spigot portion 4b tapers very slightly towards its free end. The corners of the nut head are radiussed to assist sliding in the channel, the radiussing being great enough to overcome any irregularities in the channel caused, for example, by paint droplets, but not so large as to allow rotation of the nut in the channel. The nut head is notched at its ends and has a groove in its rear face for reducing material and thereby weight and cost.

A cladding member, shown as a half-log 10, is provided with a bore 12 which receives the bolt 14. A counterbore is provided at the outer face of the log to accommodate the bolt head and washer 15. The bore diameter is large enough to receive nut spigot 4b whilst still allowing some room for swelling of the log.

On assembly of a play structure, the desired number of nuts can be fed into the channel through the opening 7 after the limb 2 and support frame has been fully erected. Each of the cladding members 10 is placed in turn against the channel with a nut spigot 4b received in the bore 12, and a bolt 14 is passed through bore 12 and tightened in the threaded hole 5 of the nut. A similar joint is used to attach each cladding log to a second frame channel spaced from and parallel to the channel 2.

This embodiment has the advantages that the nuts are easily fitted into the channels and can be adjusted along the limb without difficulty after the support frame has been erected. In addition, location of the cladding members on the nut spigots facilitates assembly enabling assembly time to be reduced.

As an alternative to the opening 7, the nuts could be inserted through an open end of the channel, the mounting plate being suitably cut away to allow this. With this arrangement the requisite number of nuts need to be engaged in the channel before it is fixed in position, e.g. against a frame upright 22, which covers and closes the open end of the channel.

Although specifically described in relation to play structures, it will be understood that the joint assembly could be used to advantage in other applications. It will also be appreciated that the joint assembly can be used to secure cladding members other than logs, such as plywood, metal sheet etc.

Claims (5)

1. A joint assembly for attaching a member to a support frame, especially in a play structure, comprising an elongate frame part in the form of a channel, an internally threaded element engaged in the channel and retained thereby against disengagement through the channel mouth, and a bolt extending through a hole in the member and threadedly engaged with said element thereby to clamp the member firmly against the channel.

2. An assembly according to claim 1, wherein the threaded element, prior to engagement with the bolt, is slidable relative to the channel for adjusting the position of the element therealong.

3. An assembly according to claim 1 or 2, wherein the element is prevented from rotation in the channel during tightening of the bolt by abutment with the side walls of the channel.

4. An assembly according to claim 1, 2 or 3, wherein the element is retained by inturned flanges at the free edges of the channel side walls.

5. An assembly according to any one of claims 1 to 4, wherein said first part comprises a substantially rectangular head and the second part is a cylindrical spigot having a threaded bore.

5. An assembly according to claim 4, wherein the element is shaped to enable insertion of the element tbrough the channel mouth followed by limited rotation of the element to engage the element behind the channel flanges.

6. An assembly according to claim 5, wherein a spring is provided for urging the element into abutment with the flanges.

7. An assembly according to claim 4, wherein the flanges are interrupted to define an opening for engagement of the element in the channel.

8. An assembly according to claim 7, wherein the opening is defined adjacent an end of the channel.

9. An assembly according to any one of the preceding claims, wherein the element comprises a first part arranged to engage in the channel and a second part arranged to project through the channel mouth, the second part entering the hole of the member.

10. An assembly according to claim 7, wherein said first part comprises a substantially rectangular head and the second part is a cylindrical spigot having a threaded bore.

11. A joint assembly for attaching a member to a support frame, substantially as herein described with reference to Figure 1 or Figures 3 and 4 of the accompanying drawings.

12. A play structure comprising a support frame including a pair of spaced parallel channels, and cladding members mounted on the frame and attached to each of the channels by an assembly as defined in any one of the preceding claims.

CLAIMS Amendments to the claims have been filed, and have the foilowing effect: Claims 1 to 10 above have been deleted or textually amended.

New or textually amended claims have been filed as follows:

1. A joint assembly for attaching a member to a support frame, especially in a play structure, comprising an elongate frame part in the form of a channel having inturned flanges at the free edges of the channel side walls an internally threaded element having a first part slidably engaged in the channel and retained by said flanges against disengagement through the channel mouth, and a second part projecting through the channel mouth into a hole in the member, and a bolt extending through the hole and threadedly engaged with said element thereby to clamp the member firmly against the channel.

2. An assembly according to claim 1 wherein the element is prevented from rotation in the channel during tightening of the bolt by abutment with the side walls of the channel.

3. An assembly according to claim 2, wherein the flanges are interrupted to define an opening for engagement of the element in the channel.

4. An assembly according to claim 3, wherein the opening is defined adjacent an end of the channel.